Nephropathy secondary to BK virus, a member of the Papoviridae family of viruses, has been recognized for some time as an important cause of allograft dysfunction in renal transplant recipients. In recent times, BK ne...Nephropathy secondary to BK virus, a member of the Papoviridae family of viruses, has been recognized for some time as an important cause of allograft dysfunction in renal transplant recipients. In recent times, BK nephropathy(BKN) of the native kidneys has being increasingly recognized as a cause of chronic kidney disease in patients with solid organ transplants, bone marrow transplants and in patients with other clinical entities associated with immunosuppression. In such patients renal dysfunction is often attributed to other factors including nephrotoxicity of medications used to prevent rejection of the transplanted organs. Renal biopsy is required for the diagnosis of BKN. Quantitation of the BK viral load in blood and urine are surrogate diagnostic methods. The treatment of BKN is based on reduction of the immunosuppressive medications. Several compounds have shown antiviral activity, but have not consistently shown to have beneficial effects in BKN. In addition to BKN, BK viral infection can cause severe urinary bladder cystitis, ureteritis and urinary tract obstruction as well as manifestations in other organ systems including the central nervous system, the respiratory system, the gastrointestinal system and the hematopoietic system. BK viral infection has also been implicated in tumorigenesis. The spectrum of clinical manifestations from BK infection and infection from other members of the Papoviridae family is widening. Prevention and treatment of BK infection and infections from other Papovaviruses are subjects of intense research.展开更多
Hyperoxaluria can cause not only nephrolithiasis and nephrocalcinosis,but also renal parenchymal disease histologically characterized by deposition of calcium oxalate crystals throughout the renal parenchyma,profound ...Hyperoxaluria can cause not only nephrolithiasis and nephrocalcinosis,but also renal parenchymal disease histologically characterized by deposition of calcium oxalate crystals throughout the renal parenchyma,profound tubular damage and interstitial inflammation and fibrosis.Hyperoxaluric nephropathy presents clinically as acute or chronic renal failure that may progress to endstage renal disease(ESRD).This sequence of events,well recognized in the past in primary and enteric hyperoxalurias,has also been documented in a few cases of dietary hyperoxaluria.Estimates of oxalate intake in patients with chronic dietary hyperoxaluria who developed chronic kidney disease or ESRD were comparable to the reported average oxalate content of the diets of certain populations worldwide,thus raising the question whether dietary hyperoxaluria is a primary cause of ESRD in these regions.Studies addressing this question have the potential of improving population health and should be undertaken,alongside ongoing studies which are yielding fresh insights into the mechanisms of intestinal absorption and renal excretion of oxalate,and into the mechanisms of development of oxalate-induced renal parenchymal disease.Novel preventive and therapeutic strategies for treating all types of hyperoxaluria are expected to develop from these studies.展开更多
We present an intuitively satisfying geometric proof of Fermat's result for positive integers that for prime moduli p, provided p does not divide a. This is known as Fermat’s Little Theorem. The proof is novel in...We present an intuitively satisfying geometric proof of Fermat's result for positive integers that for prime moduli p, provided p does not divide a. This is known as Fermat’s Little Theorem. The proof is novel in using the idea of colorings applied to regular polygons to establish a number-theoretic result. A lemma traditionally, if ambiguously, attributed to Burnside provides a critical enumeration step.展开更多
文摘Nephropathy secondary to BK virus, a member of the Papoviridae family of viruses, has been recognized for some time as an important cause of allograft dysfunction in renal transplant recipients. In recent times, BK nephropathy(BKN) of the native kidneys has being increasingly recognized as a cause of chronic kidney disease in patients with solid organ transplants, bone marrow transplants and in patients with other clinical entities associated with immunosuppression. In such patients renal dysfunction is often attributed to other factors including nephrotoxicity of medications used to prevent rejection of the transplanted organs. Renal biopsy is required for the diagnosis of BKN. Quantitation of the BK viral load in blood and urine are surrogate diagnostic methods. The treatment of BKN is based on reduction of the immunosuppressive medications. Several compounds have shown antiviral activity, but have not consistently shown to have beneficial effects in BKN. In addition to BKN, BK viral infection can cause severe urinary bladder cystitis, ureteritis and urinary tract obstruction as well as manifestations in other organ systems including the central nervous system, the respiratory system, the gastrointestinal system and the hematopoietic system. BK viral infection has also been implicated in tumorigenesis. The spectrum of clinical manifestations from BK infection and infection from other members of the Papoviridae family is widening. Prevention and treatment of BK infection and infections from other Papovaviruses are subjects of intense research.
文摘Hyperoxaluria can cause not only nephrolithiasis and nephrocalcinosis,but also renal parenchymal disease histologically characterized by deposition of calcium oxalate crystals throughout the renal parenchyma,profound tubular damage and interstitial inflammation and fibrosis.Hyperoxaluric nephropathy presents clinically as acute or chronic renal failure that may progress to endstage renal disease(ESRD).This sequence of events,well recognized in the past in primary and enteric hyperoxalurias,has also been documented in a few cases of dietary hyperoxaluria.Estimates of oxalate intake in patients with chronic dietary hyperoxaluria who developed chronic kidney disease or ESRD were comparable to the reported average oxalate content of the diets of certain populations worldwide,thus raising the question whether dietary hyperoxaluria is a primary cause of ESRD in these regions.Studies addressing this question have the potential of improving population health and should be undertaken,alongside ongoing studies which are yielding fresh insights into the mechanisms of intestinal absorption and renal excretion of oxalate,and into the mechanisms of development of oxalate-induced renal parenchymal disease.Novel preventive and therapeutic strategies for treating all types of hyperoxaluria are expected to develop from these studies.
文摘We present an intuitively satisfying geometric proof of Fermat's result for positive integers that for prime moduli p, provided p does not divide a. This is known as Fermat’s Little Theorem. The proof is novel in using the idea of colorings applied to regular polygons to establish a number-theoretic result. A lemma traditionally, if ambiguously, attributed to Burnside provides a critical enumeration step.
