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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_CreditRisksMember" xml:lang="en-US">Credit Risks [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_CreditRisksMember" xlink:to="lab_ck0001227476_CreditRisksMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_CreditSpreadRiskMember" xlink:label="loc_ck0001227476_CreditSpreadRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_CreditSpreadRiskMember" xml:lang="en-US">Credit Spread Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_CreditSpreadRiskMember" xlink:to="lab_ck0001227476_CreditSpreadRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_CybersecurityRiskMember" xlink:label="loc_ck0001227476_CybersecurityRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_CybersecurityRiskMember" xml:lang="en-US">Cybersecurity Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_CybersecurityRiskMember" xlink:to="lab_ck0001227476_CybersecurityRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_DebtorInPossessionFinancingRiskMember" xlink:label="loc_ck0001227476_DebtorInPossessionFinancingRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_DebtorInPossessionFinancingRiskMember" xml:lang="en-US">Debtor In Possession Financing Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_DebtorInPossessionFinancingRiskMember" xlink:to="lab_ck0001227476_DebtorInPossessionFinancingRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_DebtSecuritiesRiskMember" xlink:label="loc_ck0001227476_DebtSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_DebtSecuritiesRiskMember" xml:lang="en-US">Debt Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_DebtSecuritiesRiskMember" xlink:to="lab_ck0001227476_DebtSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_DeflationRiskMember" xlink:label="loc_ck0001227476_DeflationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_DeflationRiskMember" xml:lang="en-US">Deflation Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_DeflationRiskMember" xlink:to="lab_ck0001227476_DeflationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_DerivativesRiskMember" xlink:label="loc_ck0001227476_DerivativesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_DerivativesRiskMember" xml:lang="en-US">Derivatives Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_DerivativesRiskMember" xlink:to="lab_ck0001227476_DerivativesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_DurationRiskMember" xlink:label="loc_ck0001227476_DurationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_DurationRiskMember" xml:lang="en-US">Duration Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_DurationRiskMember" xlink:to="lab_ck0001227476_DurationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_EquitySecuritiesRiskMember" xlink:label="loc_ck0001227476_EquitySecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_EquitySecuritiesRiskMember" xml:lang="en-US">Equity Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_EquitySecuritiesRiskMember" xlink:to="lab_ck0001227476_EquitySecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_FinancialFuturesAndOptionsTransactionsRiskMember" xlink:label="loc_ck0001227476_FinancialFuturesAndOptionsTransactionsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_FinancialFuturesAndOptionsTransactionsRiskMember" xml:lang="en-US">Financial Futures and Options Transactions Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_FinancialFuturesAndOptionsTransactionsRiskMember" xlink:to="lab_ck0001227476_FinancialFuturesAndOptionsTransactionsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" xlink:label="loc_ck0001227476_FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" xml:lang="en-US">Floating Rate and Fixed to Floating Rate Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" xlink:to="lab_ck0001227476_FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_ForeignCurrencyRiskMember" xlink:label="loc_ck0001227476_ForeignCurrencyRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_ForeignCurrencyRiskMember" xml:lang="en-US">Foreign Currency Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_ForeignCurrencyRiskMember" xlink:to="lab_ck0001227476_ForeignCurrencyRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_ForeignEmergingMarketsIssuerRiskMember" xlink:label="loc_ck0001227476_ForeignEmergingMarketsIssuerRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_ForeignEmergingMarketsIssuerRiskMember" xml:lang="en-US">Foreign Emerging Markets Issuer Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_ForeignEmergingMarketsIssuerRiskMember" xlink:to="lab_ck0001227476_ForeignEmergingMarketsIssuerRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_FundTaxRiskMember" xlink:label="loc_ck0001227476_FundTaxRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_FundTaxRiskMember" xml:lang="en-US">Fund Tax Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_FundTaxRiskMember" xlink:to="lab_ck0001227476_FundTaxRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_GlobalEconomicRiskMember" xlink:label="loc_ck0001227476_GlobalEconomicRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_GlobalEconomicRiskMember" xml:lang="en-US">Global Economic Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_GlobalEconomicRiskMember" xlink:to="lab_ck0001227476_GlobalEconomicRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_HedgingRiskMember" xlink:label="loc_ck0001227476_HedgingRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_HedgingRiskMember" xml:lang="en-US">Hedging Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_HedgingRiskMember" xlink:to="lab_ck0001227476_HedgingRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_IncomeRiskMember" xlink:label="loc_ck0001227476_IncomeRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_IncomeRiskMember" xml:lang="en-US">Income Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_IncomeRiskMember" xlink:to="lab_ck0001227476_IncomeRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_InflationCorrelationRiskMember" xlink:label="loc_ck0001227476_InflationCorrelationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_InflationCorrelationRiskMember" xml:lang="en-US">Inflation Correlation Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_InflationCorrelationRiskMember" xlink:to="lab_ck0001227476_InflationCorrelationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_InflationRiskMember" xlink:label="loc_ck0001227476_InflationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_InflationRiskMember" xml:lang="en-US">Inflation Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_InflationRiskMember" xlink:to="lab_ck0001227476_InflationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_InverseFloatingRateSecuritiesRiskMember" xlink:label="loc_ck0001227476_InverseFloatingRateSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_InverseFloatingRateSecuritiesRiskMember" xml:lang="en-US">Inverse Floating Rate Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_InverseFloatingRateSecuritiesRiskMember" xlink:to="lab_ck0001227476_InverseFloatingRateSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_InvestmentAndMarketRiskMember" xlink:label="loc_ck0001227476_InvestmentAndMarketRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_InvestmentAndMarketRiskMember" xml:lang="en-US">Investment and Market Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_InvestmentAndMarketRiskMember" xlink:to="lab_ck0001227476_InvestmentAndMarketRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_LegislationAndRegulatoryRiskMember" xlink:label="loc_ck0001227476_LegislationAndRegulatoryRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_LegislationAndRegulatoryRiskMember" xml:lang="en-US">Legislation and Regulatory Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_LegislationAndRegulatoryRiskMember" xlink:to="lab_ck0001227476_LegislationAndRegulatoryRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_LeverageRiskMember" xlink:label="loc_ck0001227476_LeverageRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_LeverageRiskMember" xml:lang="en-US">Leverage Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_LeverageRiskMember" xlink:to="lab_ck0001227476_LeverageRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_LoanParticipationRiskMember" xlink:label="loc_ck0001227476_LoanParticipationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_LoanParticipationRiskMember" xml:lang="en-US">Loan Participation Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_LoanParticipationRiskMember" xlink:to="lab_ck0001227476_LoanParticipationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_LoanRiskMember" xlink:label="loc_ck0001227476_LoanRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_LoanRiskMember" xml:lang="en-US">Loan Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_LoanRiskMember" xlink:to="lab_ck0001227476_LoanRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_MarketDiscountFromNetAssetValueMember" xlink:label="loc_ck0001227476_MarketDiscountFromNetAssetValueMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_MarketDiscountFromNetAssetValueMember" xml:lang="en-US">Market Discount from Net Asset Value [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_MarketDiscountFromNetAssetValueMember" xlink:to="lab_ck0001227476_MarketDiscountFromNetAssetValueMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_MortgageBackedSecuritiesAndAssetBackedSecuritiesRiskMember" xlink:label="loc_ck0001227476_MortgageBackedSecuritiesAndAssetBackedSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_MortgageBackedSecuritiesAndAssetBackedSecuritiesRiskMember" xml:lang="en-US">Mortgage Backed Securities and Asset Backed Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_MortgageBackedSecuritiesAndAssetBackedSecuritiesRiskMember" xlink:to="lab_ck0001227476_MortgageBackedSecuritiesAndAssetBackedSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_OtherInvestmentCompaniesRiskMember" xlink:label="loc_ck0001227476_OtherInvestmentCompaniesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_OtherInvestmentCompaniesRiskMember" xml:lang="en-US">Other Investment Companies Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_OtherInvestmentCompaniesRiskMember" xlink:to="lab_ck0001227476_OtherInvestmentCompaniesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_PreferredAndHybridPreferredSecuritiesRiskMember" xlink:label="loc_ck0001227476_PreferredAndHybridPreferredSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_PreferredAndHybridPreferredSecuritiesRiskMember" xml:lang="en-US">Preferred and Hybrid Preferred Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_PreferredAndHybridPreferredSecuritiesRiskMember" xlink:to="lab_ck0001227476_PreferredAndHybridPreferredSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_RecentMarketConditionsMember" xlink:label="loc_ck0001227476_RecentMarketConditionsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_RecentMarketConditionsMember" xml:lang="en-US">Recent Market Conditions [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_RecentMarketConditionsMember" xlink:to="lab_ck0001227476_RecentMarketConditionsMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_ReinvestmentRiskMember" xlink:label="loc_ck0001227476_ReinvestmentRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_ReinvestmentRiskMember" xml:lang="en-US">Reinvestment Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_ReinvestmentRiskMember" xlink:to="lab_ck0001227476_ReinvestmentRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_RestrictedAndIlliquidInvestmentsRiskMember" xlink:label="loc_ck0001227476_RestrictedAndIlliquidInvestmentsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_RestrictedAndIlliquidInvestmentsRiskMember" xml:lang="en-US">Restricted and Illiquid Investments Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_RestrictedAndIlliquidInvestmentsRiskMember" xlink:to="lab_ck0001227476_RestrictedAndIlliquidInvestmentsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_ReverseRepurchaseAgreementRiskMember" xlink:label="loc_ck0001227476_ReverseRepurchaseAgreementRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_ReverseRepurchaseAgreementRiskMember" xml:lang="en-US">Reverse Repurchase Agreement Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_ReverseRepurchaseAgreementRiskMember" xlink:to="lab_ck0001227476_ReverseRepurchaseAgreementRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_SecondLienLoansAndUnsecuredLoansRiskMember" xlink:label="loc_ck0001227476_SecondLienLoansAndUnsecuredLoansRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_SecondLienLoansAndUnsecuredLoansRiskMember" xml:lang="en-US">Second Lien Loans and Unsecured Loans Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_SecondLienLoansAndUnsecuredLoansRiskMember" xlink:to="lab_ck0001227476_SecondLienLoansAndUnsecuredLoansRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_SeniorLoanAgentRiskMember" xlink:label="loc_ck0001227476_SeniorLoanAgentRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_SeniorLoanAgentRiskMember" xml:lang="en-US">Senior Loan Agent Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_SeniorLoanAgentRiskMember" xlink:to="lab_ck0001227476_SeniorLoanAgentRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_SeniorLoanRiskMember" xlink:label="loc_ck0001227476_SeniorLoanRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_SeniorLoanRiskMember" xml:lang="en-US">Senior Loan Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_SeniorLoanRiskMember" xlink:to="lab_ck0001227476_SeniorLoanRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_StructuredProductsRiskMember" xlink:label="loc_ck0001227476_StructuredProductsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_StructuredProductsRiskMember" xml:lang="en-US">Structured Products Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_StructuredProductsRiskMember" xlink:to="lab_ck0001227476_StructuredProductsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" xlink:label="loc_ck0001227476_SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" xml:lang="en-US">Subordinated Loans and Other Subordinated Debt Instruments Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" xlink:to="lab_ck0001227476_SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_SwapTransactionsRiskMember" xlink:label="loc_ck0001227476_SwapTransactionsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_SwapTransactionsRiskMember" xml:lang="en-US">Swap Transactions Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_SwapTransactionsRiskMember" xlink:to="lab_ck0001227476_SwapTransactionsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_UnratedSecuritiesRiskMember" xlink:label="loc_ck0001227476_UnratedSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_UnratedSecuritiesRiskMember" xml:lang="en-US">Unrated Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_UnratedSecuritiesRiskMember" xlink:to="lab_ck0001227476_UnratedSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_USGovernmentSecuritiesRiskMember" xlink:label="loc_ck0001227476_USGovernmentSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_USGovernmentSecuritiesRiskMember" xml:lang="en-US">US Government Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_USGovernmentSecuritiesRiskMember" xlink:to="lab_ck0001227476_USGovernmentSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_ValuationRiskMember" xlink:label="loc_ck0001227476_ValuationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_ValuationRiskMember" xml:lang="en-US">Valuation Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_ValuationRiskMember" xlink:to="lab_ck0001227476_ValuationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_WarrantsAndEquitySecuritiesRiskMember" xlink:label="loc_ck0001227476_WarrantsAndEquitySecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_WarrantsAndEquitySecuritiesRiskMember" xml:lang="en-US">Warrants and Equity Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_WarrantsAndEquitySecuritiesRiskMember" xlink:to="lab_ck0001227476_WarrantsAndEquitySecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_WhenIssuedAndDelayedDeliveryTransactionsRiskMember" xlink:label="loc_ck0001227476_WhenIssuedAndDelayedDeliveryTransactionsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_WhenIssuedAndDelayedDeliveryTransactionsRiskMember" xml:lang="en-US">When Issued and Delayed Delivery Transactions Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_WhenIssuedAndDelayedDeliveryTransactionsRiskMember" xlink:to="lab_ck0001227476_WhenIssuedAndDelayedDeliveryTransactionsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_ZeroCouponBondsOrPayInKindSecuritiesRiskMember" xlink:label="loc_ck0001227476_ZeroCouponBondsOrPayInKindSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_ZeroCouponBondsOrPayInKindSecuritiesRiskMember" xml:lang="en-US">Zero Coupon Bonds or Pay In Kind Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_ZeroCouponBondsOrPayInKindSecuritiesRiskMember" xlink:to="lab_ck0001227476_ZeroCouponBondsOrPayInKindSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_BorrowingsOutstandingMember" xlink:label="loc_ck0001227476_BorrowingsOutstandingMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_BorrowingsOutstandingMember" xml:lang="en-US">Borrowings Outstanding [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_BorrowingsOutstandingMember" xlink:to="lab_ck0001227476_BorrowingsOutstandingMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_CommonSharesMember" xlink:label="loc_ck0001227476_CommonSharesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_CommonSharesMember" xml:lang="en-US">Common Shares [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_CommonSharesMember" xlink:to="lab_ck0001227476_CommonSharesMember" />
          <link:loc xlink:type="locator" xlink:href="ck0001227476-20260731.xsd#ck0001227476_TaxableFundPreferredSharesMember" xlink:label="loc_ck0001227476_TaxableFundPreferredSharesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001227476_TaxableFundPreferredSharesMember" xml:lang="en-US">Taxable Fund Preferred Shares [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001227476_TaxableFundPreferredSharesMember" xlink:to="lab_ck0001227476_TaxableFundPreferredSharesMember" />
        </link:labelLink>
      </link:linkbase>
    </appinfo>
  </annotation>
  <import namespace="http://xbrl.sec.gov/cef/2026" schemaLocation="https://xbrl.sec.gov/cef/2026/cef-2026.xsd" />
  <import namespace="http://xbrl.sec.gov/cef-pre/2026" schemaLocation="https://xbrl.sec.gov/cef/2026/cef-2026_pre.xsd" />
  <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd" />
  <import namespace="http://xbrl.sec.gov/dei/2026" schemaLocation="https://xbrl.sec.gov/dei/2026/dei-2026.xsd" />
  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <import namespace="http://www.xbrl.org/dtr/type/2020-01-21" schemaLocation="https://www.xbrl.org/dtr/type/2020-01-21/types.xsd" />
  <element name="CommonSharesMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_CommonSharesMember" substitutionGroup="xbrli:item" />
  <element name="BorrowingsOutstandingMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_BorrowingsOutstandingMember" substitutionGroup="xbrli:item" />
  <element name="TaxableFundPreferredSharesMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_TaxableFundPreferredSharesMember" substitutionGroup="xbrli:item" />
  <element name="AntiTakeoverProvisionsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_AntiTakeoverProvisionsMember" substitutionGroup="xbrli:item" />
  <element name="BasisRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_BasisRiskMember" substitutionGroup="xbrli:item" />
  <element name="BelowInvestmentGradeRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_BelowInvestmentGradeRiskMember" substitutionGroup="xbrli:item" />
  <element name="BorrowingRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_BorrowingRiskMember" substitutionGroup="xbrli:item" />
  <element name="CallRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_CallRiskMember" substitutionGroup="xbrli:item" />
  <element name="CollateralizedDebtObligationRiskAndCollateralizedLoanObligationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_CollateralizedDebtObligationRiskAndCollateralizedLoanObligationRiskMember" substitutionGroup="xbrli:item" />
  <element name="CommonStockRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_CommonStockRiskMember" substitutionGroup="xbrli:item" />
  <element name="ContingentCapitalSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_ContingentCapitalSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="ConvertibleSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_ConvertibleSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="CounterpartyRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_CounterpartyRiskMember" substitutionGroup="xbrli:item" />
  <element name="CreditRisksMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_CreditRisksMember" substitutionGroup="xbrli:item" />
  <element name="CreditSpreadRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_CreditSpreadRiskMember" substitutionGroup="xbrli:item" />
  <element name="CybersecurityRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_CybersecurityRiskMember" substitutionGroup="xbrli:item" />
  <element name="DebtorInPossessionFinancingRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_DebtorInPossessionFinancingRiskMember" substitutionGroup="xbrli:item" />
  <element name="DebtSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_DebtSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="DeflationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_DeflationRiskMember" substitutionGroup="xbrli:item" />
  <element name="DerivativesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_DerivativesRiskMember" substitutionGroup="xbrli:item" />
  <element name="DurationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_DurationRiskMember" substitutionGroup="xbrli:item" />
  <element name="EquitySecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_EquitySecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="FinancialFuturesAndOptionsTransactionsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_FinancialFuturesAndOptionsTransactionsRiskMember" substitutionGroup="xbrli:item" />
  <element name="FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="ForeignCurrencyRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_ForeignCurrencyRiskMember" substitutionGroup="xbrli:item" />
  <element name="ForeignEmergingMarketsIssuerRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_ForeignEmergingMarketsIssuerRiskMember" substitutionGroup="xbrli:item" />
  <element name="FundTaxRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_FundTaxRiskMember" substitutionGroup="xbrli:item" />
  <element name="GlobalEconomicRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_GlobalEconomicRiskMember" substitutionGroup="xbrli:item" />
  <element name="HedgingRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_HedgingRiskMember" substitutionGroup="xbrli:item" />
  <element name="IncomeRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_IncomeRiskMember" substitutionGroup="xbrli:item" />
  <element name="InflationCorrelationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_InflationCorrelationRiskMember" substitutionGroup="xbrli:item" />
  <element name="InflationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_InflationRiskMember" substitutionGroup="xbrli:item" />
  <element name="InverseFloatingRateSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_InverseFloatingRateSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="InvestmentAndMarketRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_InvestmentAndMarketRiskMember" substitutionGroup="xbrli:item" />
  <element name="LegislationAndRegulatoryRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_LegislationAndRegulatoryRiskMember" substitutionGroup="xbrli:item" />
  <element name="LeverageRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_LeverageRiskMember" substitutionGroup="xbrli:item" />
  <element name="LoanParticipationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_LoanParticipationRiskMember" substitutionGroup="xbrli:item" />
  <element name="LoanRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_LoanRiskMember" substitutionGroup="xbrli:item" />
  <element name="MarketDiscountFromNetAssetValueMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_MarketDiscountFromNetAssetValueMember" substitutionGroup="xbrli:item" />
  <element name="MortgageBackedSecuritiesAndAssetBackedSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_MortgageBackedSecuritiesAndAssetBackedSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="OtherInvestmentCompaniesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_OtherInvestmentCompaniesRiskMember" substitutionGroup="xbrli:item" />
  <element name="PreferredAndHybridPreferredSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_PreferredAndHybridPreferredSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="RecentMarketConditionsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_RecentMarketConditionsMember" substitutionGroup="xbrli:item" />
  <element name="ReinvestmentRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_ReinvestmentRiskMember" substitutionGroup="xbrli:item" />
  <element name="RestrictedAndIlliquidInvestmentsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_RestrictedAndIlliquidInvestmentsRiskMember" substitutionGroup="xbrli:item" />
  <element name="ReverseRepurchaseAgreementRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_ReverseRepurchaseAgreementRiskMember" substitutionGroup="xbrli:item" />
  <element name="SecondLienLoansAndUnsecuredLoansRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_SecondLienLoansAndUnsecuredLoansRiskMember" substitutionGroup="xbrli:item" />
  <element name="SeniorLoanAgentRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_SeniorLoanAgentRiskMember" substitutionGroup="xbrli:item" />
  <element name="SeniorLoanRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_SeniorLoanRiskMember" substitutionGroup="xbrli:item" />
  <element name="StructuredProductsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_StructuredProductsRiskMember" substitutionGroup="xbrli:item" />
  <element name="SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" substitutionGroup="xbrli:item" />
  <element name="SwapTransactionsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_SwapTransactionsRiskMember" substitutionGroup="xbrli:item" />
  <element name="UnratedSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_UnratedSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="USGovernmentSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_USGovernmentSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="ValuationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_ValuationRiskMember" substitutionGroup="xbrli:item" />
  <element name="WarrantsAndEquitySecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_WarrantsAndEquitySecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="WhenIssuedAndDelayedDeliveryTransactionsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_WhenIssuedAndDelayedDeliveryTransactionsRiskMember" substitutionGroup="xbrli:item" />
  <element name="ZeroCouponBondsOrPayInKindSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="ck0001227476_ZeroCouponBondsOrPayInKindSecuritiesRiskMember" substitutionGroup="xbrli:item" />
</schema>
