Domestic cats and dogs are carnivores that have evolved differentially in the nutrition and metabolism of amino acids.This article highlights both proteinogenic and nonproteinogenic amino acids.Dogs inadequately synth...Domestic cats and dogs are carnivores that have evolved differentially in the nutrition and metabolism of amino acids.This article highlights both proteinogenic and nonproteinogenic amino acids.Dogs inadequately synthesize citrulline(the precursor of arginine)from glutamine,glutamate,and proline in the small intestine.Although most breeds of dogs have potential for adequately converting cysteine into taurine in the liver,a small proportion(1.3%-2.5%)of the Newfoundland dogs fed commercially available balanced diets exhibit a deficiency of taurine possibly due to gene mutations.Certain breeds of dogs(e.g.,golden retrievers)are more prone to taurine deficiency possibly due to lower hepatic activities of cysteine dioxygenase and cysteine sulfinate decarboxylase.De novo synthesis of arginine and taurine is very limited in cats.Thus,concentrations of both taurine and arginine in feline milk are the greatest among domestic mammals.Compared with dogs,cats have greater endogenous nitrogen losses and higher dietary requirements for many amino acids(e.g.,arginine,taurine,cysteine,and tyrosine),and are less sensitive to amino acid imbalances and antagonisms.Throughout adulthood,cats and dogs may lose 34%and 21%of their lean body mass,respectively.Adequate intakes of high-quality protein(i.e.,32%and 40%animal protein in diets of aging dogs and cats,respectively;dry matter basis)are recommended to alleviate aging-associated reductions in the mass and function of skeletal muscles and bones.Pet-food grade animal-sourced foodstuffs are excellent sources of both proteinogenic amino acids and taurine for cats and dogs,and can help to optimize their growth,development,and health.展开更多
BACKGROUND Cat scratch disease(CSD)is the most common human infection caused by Barto-nella henselae(B.henselae).The main manifestation is self-limited lymphaden-opathy that primarily affects adolescents,and typically...BACKGROUND Cat scratch disease(CSD)is the most common human infection caused by Barto-nella henselae(B.henselae).The main manifestation is self-limited lymphaden-opathy that primarily affects adolescents,and typically resolves without treat-ment within 2-4 months.However,individuals with compromised immune systems or immunodeficiency require specific antibacterial therapy following diagnosis.Due to its low incidence,nonspecific clinical manifestations,and diagnostic limitations,this condition often poses challenges for clinicians in terms of missed diagnoses and misdiagnoses.CASE SUMMARY The child was ultimately diagnosed with CSD.The primary manifestations included nocturnal fever,enlargement of lymph nodes in the neck,axilla and groin,and suspected brucellosis;however,both brucellosis tests conducted during the course of the illness yielded negative results.Bone marrow cytology indicated stimulated proliferation.Lymph node biopsy indicated hyperplasia of lymphoid tissue in the cervical lymph nodes(right),with combined immunohisto-chemical findings indicating reactive hyperplasia.Immunohistochemical analysis revealed CD20 B(+),CD3 T(+),BCL-6(+),and BCL-2(-).CD21 FDC networks were present and Ki67 expression in the germinal center was~80%.Blood next-generation sequencing indicated B.henselae sequence number was 3.Serological test results demonstrated positive antibody response to B.henselae IgG(+),B.henselae IgM(+),Bartonella quintana(B.quintana)IgG(-)and B.quintana IgM(-),and the final diagnosis was CSD.CONCLUSION In patients presenting with fever at night and swollen lymph nodes of unknown origin,CSD should be considered.展开更多
Psychophysical experiments on human and animal subjects have proven that aged individuals show significantly reduced visual contrast sensitivity compared with young adults.To uncover the possible neural mechanisms,we ...Psychophysical experiments on human and animal subjects have proven that aged individuals show significantly reduced visual contrast sensitivity compared with young adults.To uncover the possible neural mechanisms,we used extracellular single-unit recording techniques to examine the response of V1（primary visual cortex） neurons as a function of visual stimulus contrast in both old and young adult cats（Felis catus）.The mean contrast sensitivity of V1 neurons to visual stimuli in old cats decreased significantly relative to young adult cats,consistent with findings reported in old primates.These results indicate that aging can affect contrast sensitivity of visual cortical cells in both primate and non-primate mammalian animals,and might contribute to the reduction of perceptual visual contrast sensitivity in aged individuals.Further,V1 cells of old cats exhibited increased responsiveness,decreased signal-to-noise ratio,and enlarged receptive field（RF） size compared with that of young adult cats,which indicated that decreased contrast sensitivity of V1 neurons accompanied a reduction of intracortical inhibition during senescence.展开更多
基金This work was supported by Texas A&M AgriLife Research(H-8200).
文摘Domestic cats and dogs are carnivores that have evolved differentially in the nutrition and metabolism of amino acids.This article highlights both proteinogenic and nonproteinogenic amino acids.Dogs inadequately synthesize citrulline(the precursor of arginine)from glutamine,glutamate,and proline in the small intestine.Although most breeds of dogs have potential for adequately converting cysteine into taurine in the liver,a small proportion(1.3%-2.5%)of the Newfoundland dogs fed commercially available balanced diets exhibit a deficiency of taurine possibly due to gene mutations.Certain breeds of dogs(e.g.,golden retrievers)are more prone to taurine deficiency possibly due to lower hepatic activities of cysteine dioxygenase and cysteine sulfinate decarboxylase.De novo synthesis of arginine and taurine is very limited in cats.Thus,concentrations of both taurine and arginine in feline milk are the greatest among domestic mammals.Compared with dogs,cats have greater endogenous nitrogen losses and higher dietary requirements for many amino acids(e.g.,arginine,taurine,cysteine,and tyrosine),and are less sensitive to amino acid imbalances and antagonisms.Throughout adulthood,cats and dogs may lose 34%and 21%of their lean body mass,respectively.Adequate intakes of high-quality protein(i.e.,32%and 40%animal protein in diets of aging dogs and cats,respectively;dry matter basis)are recommended to alleviate aging-associated reductions in the mass and function of skeletal muscles and bones.Pet-food grade animal-sourced foodstuffs are excellent sources of both proteinogenic amino acids and taurine for cats and dogs,and can help to optimize their growth,development,and health.
基金Supported by Shaanxi Natural Science Foundation,No.2020SF-004.
文摘BACKGROUND Cat scratch disease(CSD)is the most common human infection caused by Barto-nella henselae(B.henselae).The main manifestation is self-limited lymphaden-opathy that primarily affects adolescents,and typically resolves without treat-ment within 2-4 months.However,individuals with compromised immune systems or immunodeficiency require specific antibacterial therapy following diagnosis.Due to its low incidence,nonspecific clinical manifestations,and diagnostic limitations,this condition often poses challenges for clinicians in terms of missed diagnoses and misdiagnoses.CASE SUMMARY The child was ultimately diagnosed with CSD.The primary manifestations included nocturnal fever,enlargement of lymph nodes in the neck,axilla and groin,and suspected brucellosis;however,both brucellosis tests conducted during the course of the illness yielded negative results.Bone marrow cytology indicated stimulated proliferation.Lymph node biopsy indicated hyperplasia of lymphoid tissue in the cervical lymph nodes(right),with combined immunohisto-chemical findings indicating reactive hyperplasia.Immunohistochemical analysis revealed CD20 B(+),CD3 T(+),BCL-6(+),and BCL-2(-).CD21 FDC networks were present and Ki67 expression in the germinal center was~80%.Blood next-generation sequencing indicated B.henselae sequence number was 3.Serological test results demonstrated positive antibody response to B.henselae IgG(+),B.henselae IgM(+),Bartonella quintana(B.quintana)IgG(-)and B.quintana IgM(-),and the final diagnosis was CSD.CONCLUSION In patients presenting with fever at night and swollen lymph nodes of unknown origin,CSD should be considered.
基金Supported by National Natural Science Foundation of China(31171082)Natural Science Foundation of Anhui Province(070413138)the Key Research Foundation of Anhui Province Education Department(KJ2009A167)
文摘Psychophysical experiments on human and animal subjects have proven that aged individuals show significantly reduced visual contrast sensitivity compared with young adults.To uncover the possible neural mechanisms,we used extracellular single-unit recording techniques to examine the response of V1（primary visual cortex） neurons as a function of visual stimulus contrast in both old and young adult cats（Felis catus）.The mean contrast sensitivity of V1 neurons to visual stimuli in old cats decreased significantly relative to young adult cats,consistent with findings reported in old primates.These results indicate that aging can affect contrast sensitivity of visual cortical cells in both primate and non-primate mammalian animals,and might contribute to the reduction of perceptual visual contrast sensitivity in aged individuals.Further,V1 cells of old cats exhibited increased responsiveness,decreased signal-to-noise ratio,and enlarged receptive field（RF） size compared with that of young adult cats,which indicated that decreased contrast sensitivity of V1 neurons accompanied a reduction of intracortical inhibition during senescence.
