Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mannitol, 3-O-methylglucose and lactulose administered orally are used to investigate small intestinal absorption pathways and mucosal integrity. Current methods of analysis include thin-layer chromatography, gas chromatography (GC) and enzymatic analysis, which require separate estimation of mono- and disaccharides and for GC, prior derivatization. We describe a high-pressure anion-exchange chromatographic method coupled with pulsed electrochemical detection allowing simultaneous measurement of all three sugars and its clinical application in monitoring intestinal damage in human immunodeficiency virus (HIV) infection. Sample preparation is simple and fast. All sugars are resolved within 10 min. Mean recovery is 93.3% for all sugars and the overall relative standard deviation is 4.2%. Intestinal permeability (lactulose/mannitol ratio) rises with disease progression to AIDS, indicating mucosal damage. The greatest increase in permeability is associated with chronic diarrhoea. The method is an ideal non-invasive test to assess gut mucosal damage in HIV infection.
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PMID:Analysis of multiple sugar probes in urine and plasma by high-performance anion-exchange chromatography with pulsed electrochemical detection. Application in the assessment of intestinal permeability in human immunodeficiency virus infection. 834 26

In human immune deficiency virus (HIV) disease, direct infection of heart tissue with HIV and repeated intestinal infections with opportunistic pathogens are thought to be the main cause of cardiac disease and diarrhoea respectively. A role for autoimmune phenomena may also be involved in the pathogeny of HIV disease. In this study, we demonstrate that immunoglobulins from the A and G classes from HIV positive patients are able to interfere with the function of the muscarinic cholinergic receptors from heart and gut. Both IgA and IgG HIV+ preparations decreased the tension of isolated atria and increased the tension of isolated ileum. The mechanical effect of carbachol was inhibited in both atria and ileum preparations, when they were preincubated with either IgA or IgG HIV+ fractions. An inhibitor of muscarinic cholinergic receptors (atropine) impaired the negative inotropic action of HIV+ immunoglobulins (Ig) on the heart and prevented the positive inotropic effect of HIV+ Igs on ileum. HIV+ IgA fraction was approximately ten fold more potent to interfere with the cholinergic function as compared to the IgG fraction. These results suggest that antibodies present in HIV+ serum may also modulate muscle's cholinergic activity in the heart and ileum from HIV+patients.
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PMID:Autoantibodies in HIV-infected patients that modulate the cholinergic activity of heart and gut tissue. 834 73

Fever, loss of weight, anaemia, hepatosplenomegaly and lymphadenopathy developed in two HIV-infected patients. At first malignant lymphoma with septicaemia was thought to be the cause. In both patients Salmonella enteritidis was isolated by blood culture and found to be sensitive against the antibiotics that were given (5 g azlocillin and 2 g cefotaxime, three times daily each; additionally in case 2, metronidazole, 500 mg three times daily). Because bone-marrow biopsy demonstrated acid-fast rods, antimycobacterial treatment was started (isoniazid 300 mg/d, rifampicin 600 mg/d, ethambutol 1,200 mg/d and pyrazinamide 2 g/d). Despite this the patients died of septic shock. Histological examination revealed massive amounts of acid-fast rods in spleen, liver, gut and bone marrow. Polymerase chain reaction and sequencing identified the structure as that of the recently discovered M. genavense.
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PMID:[Mycobacterium genavense infection in AIDS]. 844 11

The effect of HIV infection on intestinal lamina propria macrophage subsets was investigated in 41 patients at various stages of HIV infection (asymptomatic HIV infection, n = 17; AIDS, n = 24). Duodenal biopsies taken from HIV patients at endoscopy were snap frozen and cryostat sections cut for immunohistochemical staining. MoAbs CD68 (EBM11, pan-macrophage marker), RFD1 (antigen-presenting cells) and RFD7 (mature phagocytic macrophages) were used to identify cell subsets using indirect immunoperoxidase or alkaline phosphatase. Double immunofluorescence using MoAbs to HIV proteins (p24, p17 and gp120) and RFD1 were used to identify HIV-infected antigen-presenting cells. Double immunofluorescence was also used to identify macrophages that expressed both RFD1 and RFD7 ('suppressor' macrophages). Intensity of HLA-DR expression in lamina propria cells was investigated using a MoAb to HLA-DR directly conjugated to glucose oxidase. The results show that there was no difference in overall density of macrophages, but there was a significant decrease in dendritic cells (RFD1+) in all clinical stages of HIV. There was no difference in the density of RFD7+ macrophages, nor was there a difference intensity of HLA-DR expression in lamina propria cells. Only four HIV-infected cells were positively identified in the 41 patients. This result suggests that the antigen-presenting arm of mucosal immune defences may be seriously compromised in HIV infection, and represents a further insult to mucosal immunity already impaired as a result of loss of CD4+ T lymphocytes. This may contribute to development of opportunist infection in the gut.
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PMID:Mucosal macrophage subsets of the gut in HIV: decrease in antigen-presenting cell phenotype. 851 76

A wide range of abnormal findings can be seen at abdominal ultrasonography in patients with HIV infection. The most frequent findings, hepatomegaly, splenomegaly, and enlarged lymph nodes, are nonspecific, however. Increased echogenicity or focal lesions of parenchymal organs, dilated bile ducts, nephromegaly, gut wall thickening or abscesses are uncommon findings. If there is clinical suspicion for a treatable disease, abnormalities seen on ultrasound examination of HIV-infected patients need to be confirmed by guided biopsy.
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PMID:[Ultrasound findings in HIV patients]. 865 99

We have previously shown (Sunkara et al., 1989; Taylor et al., 1991) that 6-o-butanoyl castanospermine (BuCast) was a 30-50-fold better inhibitor of HIV syncytia formation than castanospermine (Cast). Radiolabeled Cast and BuCast were used to study the uptake and metabolism of these compounds in cultured cells and in mice. BuCast was preferentially taken up by cells compared to Cast. Approximately 30-50-fold higher radioactivity was found in cells treated with BuCast compared to cells treated with Cast during the initial 4-6 h of labeling. HPLC analysis showed that once BuCast was taken up by cells, it was rapidly converted to Cast. Mice given oral doses of BuCast had 5-10-fold higher levels of Cast in the plasma and tissues as compared to Cast treated mice. However, when the compounds were given i.v., the levels of plasma and tissue radioactivity obtained from Cast of BuCast were equivalent suggesting rapid conversion of BuCast to Cast in the blood. In mice orally treated with BuCast, HPLC analysis suggested that only Cast was found in the plasma and tissues. With multiple dosing of mice, additive results were obtained, suggesting that multiple doses may be used to obtain higher concentrations of the compound in the target cells. These data suggest that the lipophilic properties of butanoyl side chain on the Cast ring makes BuCast significantly better absorbed, and this may help to alleviate some of the gut toxicity associated with Cast treatment.
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PMID:Uptake and metabolism of BuCast: a glycoprotein processing inhibitor and a potential anti-HIV drug. 872 92

The most common route of transmission of HIV is via the mucosa. We compared human and macaque intestinal epithelia to determine whether the SIV macaque system can be used as a model to study HIV transmission by the rectal route. The overall morphology of the macaque gut mucosa is very similar to that of humans. Differentiation markers follow the same pattern as in the human system. The carcinoembryonic antigen (CEA) is apical in epithelial cells of the rectum and is absent from the small intestine. Blood group H antigen is expressed by enterocytes but not by colonocytes or rectocytes. Galactosylceramide, a potential alternative receptor for HIV in epithelial cells, is expressed in all intestinal segments as in humans. In absorptive cells it is apical and intracellular in the rectum, colon, and cecum, whereas it is only intracellular in small intestine. In goblet cells the galactosylceramide is present in intracellular vacuoles in all segments. It is also present on the membrane of mucous granules in colon and small intestine but not in rectum. We therefore believe that the macaque digestive tract may constitute a good model for the human digestive tract in the transmission of lentiviruses.
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PMID:Differential distribution of galactosylceramide, H antigen, and carcinoembryonic antigen in rhesus macaque digestive mucosa. 877 68

Viral vaccines which stimulate the humoral immune response in humans have been successful in preventing most of the known virus diseases except dengue fever, respiratory syncytial virus infections and HIV-1-related AIDS. Burke [1] raised a concern that anti-HIV-1 antibodies may add a risk factor to immunized individuals infected with HIV-1. An approach to develop HIV-1 vaccines capable of stimulating anti-HIV-1 cytotoxic T cells requires an understanding of the importance of epidermal and epithelial Langerhans cells (LC). These cells are professional antigen-presenting cells which express HLA class I and class II molecules. Epithelial LC are present in a specific layer in the skin, genitalia and gut and may be accessible to viral antigens by local application in a vehicle for transepithelial transport of viral proteins/peptides (designated "HIV-1 Peplotion vaccine"). This approach is supported by the reports that HIV-1 gp160 in ISCOM induced MHC class I CTL response [2], mixing of cationic lipids with viral proteins formed complexes which were delivered to cell cytoplasm and the degraded peptides stimulated CTLs by HLA class I mechanism [3] and viral proteins encapsulated in pH-sensitive liposomes administered to LC induced primary antiviral CTLs [4]. Current studies in our laboratory deal with (a) selection of the vehicle for transepidermal transport of peptides and the conditions for selective uptake by epidermal LC [5]; (b) computer analysis of HIV-1 proteins to detect the putative proteolytic cleavage peptides with amino acid motifs which allow association with different known HLA class I haplotype molecules on LCs and synthetic peptide uptake from "without" by LC. The "HIV-1 Peplotion vaccine", when developed, will be useful for continual stimulation of antiviral CTLs in uninfected individuals and HIV-1 carriers by repetitive application to skin, genitalia and gut. The "Peplotion vaccine" will be applied by vaccinees, will be affordable for all human-populations and, hopefully, will be highly efficient.
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PMID:"HIV-peplotion vaccine"--a novel approach to protection against AIDS by transepithelial transport of viral peptides to Langerhans cells for long-term antiviral CTL response. (A review). 880 38

Anorectal disorders are commonly encountered in the practice of emergency medicine. Most can be diagnosed and treated in the emergency department setting. Almost all anorectal disorders once diagnosed and treated in the emergency department need appropriate follow-up to ensure adequacy of treatment, for further possible diagnostic procedures (e.g., endoscopy, biopsy), or for definitive treatment. Hemorrhoids are the most prevalent anorectal disorder and are the most common cause of hematochezia. Treatment is dependent on the degree of hemorrhoid prolapse and symptoms. Most cases can be treated by conservative medical treatment (e.g., dietary changes, sitz baths) or nonsurgical procedures (e.g., rubber band liagation, infrared coagulation). Surgical excision of symptomatic thrombosed external hemorrhoids is indicated if within 48 to 72 hours of pain onset. Anal fissures are one of the most common causes of anorectal pain. They are most frequently idiopathic, and most are located in the posterior midline of the anal canal. Most anal fissures are adequately treated by a medical approach using sitz baths, stool softeners, and analgesics. If the anal fissure becomes chronic and is not responsive to medical therapy, a lateral sphincterotomy of the internal anal sphincter is the surgical procedure of choice. Pharmacologic treatment (botulinum toxin or nitroglycerin ointment) to decrease internal anal sphincter tone has shown promise in the treatment of anal fissure. Anorectal abscesses are categorized into four types: perianal, ischiorectal, intersphincteric, and supralevator. Most are idiopathic and contain mixed aerobic-anaerobic pathogens. Fistula formation varies from 25% to 50% and is much more common with gut-derived organisms (e.g., E. coli, B. fragilis). Definitive treatment for an anorectal abscess is timely surgical incision and drainage to prevent more serious complications (e.g., serious infection, extension of the abscess). Anal carcinomas are infrequent, the majority of them being squamous cell or epidermoid carcinomas. The emergency physician must maintain a high index of suspicion and obtain a biopsy of suspicious lesions in order not to miss the diagnosis of a cancer. The most common presenting complaint of anal tumors is rectal bleeding. Combination chemotherapy and radiotherapy have shown promising results in the treatment of anal canal tumors. Bacterial, viral, and protozoal infections can be transmitted to the anorectum via anoreceptive intercourse. Such infections must be considered when a patient presents with rectal pain or discharge, tenesmus, or rectal or perineal ulcers. Proctosigmoidoscopy and rectal cultures may be necessary to determine the cause. Potential rectal complications of HIV infection include infectious diarrhea, acyclovir-resistant strains of HSV2, Kaposi's sarcoma, lymphoma, and squamous cell carcinoma. Rectal injuries may result from penetrating or blunt trauma, iatrogenic injuries, or foreign bodies. Rectal injury should be suspected when a patient presents with low abdominal, pelvic, or perineal pain or blood per rectum after sustaining trauma or undergoing an endoscopic or surgical procedure. Tetanus prophylaxis, intravenous antibiotics, and surgical intervention are indicated in all but superficial rectal tears.
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PMID:Anorectal disorders. 892 68

The wasting syndrome is well known in HIV infected patients. Predominant free fatty mass deletion is achieved. The weight loss results from decrease of food intake, from gut disorders due to HIV or opportunistic infections. Metabolic disorders are reported too. Breakdown of carbohydrates and proteins presents energy source. Raised free fatty acid turn over and hypertriglyceridemia are reported. Polyunsatured fatty acid level is raised inducing free radicals increase. Free radicals delete immune functions (apoptosis). Vitamin and trace element decrease worsen negative effects of free radicals.
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PMID:[Malnutrition and HIV infection]. 900 47


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