Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Seven-day-old mice were infected orally with murine rotavirus (EDIM) and regions of the gut examined at 24 h intervals up to 7 days by electron microscopy. Structural changes were correlated with data on viral antigen production, thymidine kinase activity, and clinical signs of diarrhea. No pathological changes were detected in the colon. Infection and structural damage were confined to the small intestine, with middle regions showing the most pronounced changes. Constriction of villus bases, edema of the lamina propria, and vacuolation of enterocytes occurred at 24 h postinfection (PI), i.e., before evidence of major virus replication. Transient villus atrophy occurred at 48 h PI. Recovery of villus length was evident by 72 h PI accompanied by evidence of marked enterocyte replication at villus bases. Many enterocytes were damaged with little evidence for the presence of virus particles. By 96 h PI, villi had almost recovered from infection although some enterocytes were still damaged; no virus particles were detected in these cells. A second phase of villus damage and edema of the lamina propria occurred at 120 h PI; the pathology resembled that at 24-48 h PI. By 144 to 168 h PI, recovery of the mucosa from infection was virtually complete. We suggest that many of the pathological features following rotavirus infection result from rotavirus-induced ischemia of villi and that diarrhea results from malabsorption of fluid by damaged villi and hypersecretion of ions released from increased numbers of dividing cells at villus-crypt borders.
 ...
PMID:An electron microscopic investigation of time-related changes in the intestine of neonatal mice infected with murine rotavirus. 283 83

During the past two decades, the essentiality of zinc for man has been established. Deficiency of zinc in man due to nutritional factors and several diseased states has been recognized. High phytate content of cereal proteins decreases availability of zinc; thus the prevalence of zinc deficiency is likely to be high in a population subsisting mainly on cereal proteins. Alcoholism is known to cause hyperzincuria and thus may play a role in producing zinc deficiency in man. Malabsorption, cirrhosis of the liver, chronic renal disease and other chronically debilitating diseases may similarly induce zinc deficiency in human subjects. A severe deficiency of zinc has recently been recognized to occur in patients with sickle cell anemia and a beneficial effect of zinc therapy in such patients has been reported. Growth retardation, male hypogonadism, skin changes, poor appetite, mental lethargy and delayed wound healing are some of the manifestations of chronically zinc-deficient human subjects. Taste abnormalities, correctable with zinc supplementation, have been observed in uremic subjects. Recently, abnormal dark adaptation related to zinc deficiency in patients with cirrhosis of the liver and sickle cell disease has been reported. In severely zinc-deficient patients, dermatological manifestations, diarrhea, alopecia, mental disturbances and intercurrent infections predominate and if untreated the condition becomes fatal. Zinc deficiency is known to affect testicular functions adversely in man and animals. This effect of zinc is at the end organ level and it appears that zinc is essential for spermatogenesis and testosterone steroidogenesis. Zinc is involved in many biochemical functions. Several zinc metalloenzymes have been recognized in the past decade. Zinc is required for each step of cell cycle in microorganisms and is essential for DNA synthesis. Thymidine kinase, RNA polymerase, DNA-polymerase from various sources and RNA-dependent DNA polymerase from viruses have been shown to be zinc-dependent enzymes. Zinc also regulates the activity of RNase; thus the catabolism of RNA appears to be zinc-dependent. The effect of zinc on protein synthesis may be attributable to its vital role in nucleic acid metabolism. The activities of many zinc-dependent enzymes have been shown to be affected adversely in zinc-deficient tissues. Three enzymes, alkaline phosphatase, carboxypeptidase and thymidine kinase, appear to be most sensitive to zinc restriction in that their activities are affected adversely within three to six days of institution of a zinc-deficient diet to experimental animals.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Zinc deficiency in human subjects. 636 78

The majority of transmissions occur as a consequence of inapparent infection in the source contact, as asymptomatic viral excretion in individuals with recurrent infection. The development of type specific serological assays has allowed for a more accurate determination of herpes simplex virus (HSV) 2 prevalence and has revealed that the prevalence of HSV 2 in sexually transmitted disease clinic attenders varies from 8%-83%, in female prostitutes from 75%-96% and in antenatal clinic attenders from 6%-53%. The majority of individuals (+/-60%) exposed to HSV 2 do not develop any symptoms. Patients treated for primary genital herpes are likely to resume sexual intercourse earlier than those who do not. Long-term suppressive acyclovir will result in decrease in clinical symptoms and viral excretion and may decrease the opportunity for HSV transmission. Acyclovir is the drug of choice for the treatment of primary genital herpes and for long-term acyclovir suppression. Two new drugs, valaciclovir and famciclovir, are currently under investigation. Failure to respond to acyclovir may be due to inadequate dose, malabsorption, another condition, or resistance. Resistance is rare and occurs mainly in profoundly immunosuppressed individuals, and is usually due to the development of thymidine kinase deficient mutants. Treatment with intravenous foscarnet is usually successful. Patients with genital herpes have a number of emotional problems, particularly if the condition recurs. Recent studies suggest that emotional stress does not precipitate recurrences, but rather recurrences cause stress. Long-term acyclovir suppression can decrease psychological morbidity in patients with frequent recurrences.
 ...
PMID:Recent advances in genital herpes. 884 93