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Biomedical subjects

R M Strauss

Publications and source records attributed to R M Strauss.

32 records · Page 2Linked to original sources
PubMed2001

Serum hyaluronic acid in patients with veno-occlusive disease following bone marrow transplantation.

The development of hepatic veno-occlusive disease following bone marrow transplantation is associated with high-dose combination cytoreductive therapy. Experimental models have suggested that drug-induced injury to hepatic sinusoidal endothelial cells is involved in the pathogenesis of this syndrome. Hyaluronic acid is a polysaccharide that is metabolized, almost exclusively, by hepatic sinusoidal endothelial cells. The aim of the present study was to evaluate serum hyaluronic acid as a marker for endothelial cell injury in patients with veno-occlusive disease following bone marrow transplantation. Hyaluronic acid was measured in sera from patients with and without veno-occlusive disease using an enzyme-linked protein binding assay. Mean peak serum hyaluronic acid levels were significantly greater in patients who had a diagnosis of VOD compared to those transplant patients who did not, 1173.4 +/- 982.9 vs 444.9 +/- 735.6 ng/ml (P = 0.01). Serial serum samples obtained from a separate cohort of patients also demonstrated that serum hyaluronic acid levels were higher in patients with moderate or severe veno-occlusive disease compared to those with none or mild disease at days 7, 17 and 25 following transplantation (greatest difference at day 25: 366 +/- 327 vs 126 +/- 151, P = 0.01). Serum hyaluronic acid levels are increased in veno-occlusive disease and increase over time in patients with severe disease. Further studies are required to determine if elevated serum hyaluronic acid levels are due to decreased clearance by injured hepatic sinusoidal endothelial cells or increased production from early hepatic fibrogenesis associated with the acute liver injury.

Adult↗
PubMed2001

Successful treatment of molluscum contagiosum with topical imiquimod in a severely immunocompromised HIV-positive patient.

Molluscum contagiosum is a common viral infection in the immuno-compromised HIV-positive patient where it is often severe and affecting the face and neck. It is frequently resistant to conventional, locally destructive therapies. Anecdotal evidence suggests that the immunomodulatory drug imiquimod might be a valid therapeutic option in this group of patients. We report the case of a severely immunocompromised HIV-positive patient with resistant facial molluscum contagiosum lesions that responded to topical imiquimod. The response to therapy and the possible implications for pathogenesis are discussed.

AIDS-Related Opportunistic Infections↗
PubMed1999

Selected drug complications and treatment conflicts in the presence of coexistent diseases.

The presence of different coexistent systemic diseases often times complicates the selection of the appropriate treatment of an underlying rheumatologic condition. In this article, some controversial treatment conflicts that are frequently encountered in the daily practice of rheumatology are clarified and guidelines for the best available therapeutic options are provided.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1997

Hepatic hydrothorax.

Ascites is a common manifestation of portal hypertension in patients with cirrhosis. Approximately 5% of patients with cirrhosis may develop a pleural effusion. This is usually right sided. In the absence of cardiac or lung disease, the presence of a pleural effusion in a cirrhotic patient is known as hepatic hydrothorax. Small volumes of fluid within the pleura may be associated with significant respiratory symptoms which require the clinician to rapidly remove the fluid. The development of hepatic hydrothorax is secondary to passage of ascites from the abdomen to the pleural space via defects in the diaphragm. Once the diagnosis of hepatic hydrothorax is established with certainty, medical therapy with salt restriction and diuretics is initiated. When these measures are ineffective the patient has refractory hepatic hydrothorax. Based on current studies, transjugular intrahepatic portal systemic shunts appear to be the most effective form of treatment for these patients.

Ascites↗
PubMed1994

Transjugular intrahepatic portal systemic shunt for the management of symptomatic cirrhotic hydrothorax.

OBJECTIVE: To investigate the safety and effectiveness of performing transjugular intrahepatic portal systemic shunt (TIPS) for the management of symptomatic cirrhotic hydrothorax in patients with advanced cirrhosis. METHODS: TIPS was performed by standard technique after portal vein patency had been established by ultrasound. Portal-hepatic vein pressure gradient was determined before and after placement of the shunt. A portal-hepatic vein gradient of less than 12 mm Hg was the treatment goal. RESULTS: Five patients underwent TIPS placement over an 11-month period. Despite use of diuretics, the patients had required a median of seven thoracenteses (range 2-11) for control of symptoms preceding placement of the shunt. A TIPS was placed without serious complications in all five patients. In two patients, insertion of the shunt was associated with no further need for thoracentesis. The other three patients had recurrent need for thoracentesis. These three patients were found to have occluded shunts which were rendered patent by angioplasty and/or urokinase. Subsequently, two required no further thoracentesis, whereas, in the other patient, the need for thoracentesis was decreased dramatically. CONCLUSIONS: TIPS appears to be a safe and useful technique for the management of patients with symptomatic cirrhotic hydrothorax that is refractory to medical therapy. Recurrence of the pleural effusion after placement of TIPS may be an indication of shunt occlusion.

Adult↗
PubMed1993

Malignant hepatic tumors: safety of high-dose percutaneous ethanol ablation therapy.

The authors retrospectively analyzed clinical records to determine the safety and complication rate of percutaneous ethanol ablation therapy with more than 10 mL of ethanol administered per session for treatment of malignant hepatic tumors. Ten patients underwent a total of 35 sessions with 10 mL or more of ethanol, and four underwent 18 sessions with 10 mL or less. No serious complications occurred with any dose. Pain and fever were the most common complications at all doses, and the higher frequency of these at larger ethanol volumes may be related to the greater degree of tumor necrosis induced by the larger volume.

Adult↗
PubMed1991

Coexpression of galanin and adrenocorticotropic hormone in human pituitary and pituitary adenomas.

Galanin is a neuropeptide that regulates the secretion of several pituitary hormones, including prolactin (PRL) and growth hormone (GH). Galaninlike immunoreactivity (Gal-IR) and galanin mRNA in the rat anterior pituitary is cell lineage specific, with predominant expression in lactotrophs and somatotrophs. The authors examined the cellular distribution of human Gal-IR in seven normal postmortem pituitaries and 62 pituitary tumors by immunoperoxidase staining. In contrast to the rat, Gal-IR in human anterior pituitaries was present in corticotrophs scattered throughout the gland, but not in lactotrophs, somatotrophs, thyrotrophs, or gonadotrophs. Distinct Gal-IR also was present in hyperplastic and neoplastic corticotrophs in 19 of 22 patients with Cushing's disease. In noncorticotroph cell tumors, unequivocal Gal-IR was present in 5 of 11 GH-secreting tumors associated with clinical acromegaly, 9 of 18 nonfunctioning pituitary adenomas, and 2 of 14 prolactinomas. Of these galanin-positive tumors, four of the five GH-secreting adenomas, six of the nine nonfunctioning adenomas, and both of the prolactinomas also contained adrenocorticotropic hormone immunoreactivity (ACTH-IR). Immunostaining and in situ hybridization on adjacent sections using an 35S-labeled probe complementary to human galanin mRNA demonstrated predominant galanin expression in normal corticotrophs. Immunoelectron microscopy confirmed the presence of Gal-IR in pituitary cells characteristic of corticotrophs in both normal and neoplastic pituitaries. Thus, as in the rat, galanin gene expression in the human pituitary is cell-type specific. Unlike the rat, however, human galanin gene expression is restricted to the corticotroph lineage. Studies of tumors confirmed the observed coexpression of galanin and adrenocorticotropic hormone. The divergent cell type specificity of galanin production in human and rat pituitaries reflects different patterns of gene activation in these two species. In addition, these results suggest that galanin in the human pituitary may participate locally in the regulation of the hypothalamic-pituitary-adrenal axis.

Adenoma↗
PubMed1990

Association of Helicobacter pylori infection with dyspeptic symptoms in patients undergoing gastroduodenoscopy.

PURPOSE: To determine the prevalence of Helicobacter pylori in patients with non-ulcer dyspepsia and ulcer disease as well as in a control population undergoing endoscopic retrograde cholangiopancreatography (ERCP) for suspected pancreatic or biliary disease. PATIENTS AND METHODS: Forty-six eligible patients undergoing upper endoscopy at Massachusetts General Hospital were studied over a period of 18 months, as well as 24 patients undergoing ERCP for presumed pancreatic or biliary disease. Two biopsy specimens from the fundus and two from the antrum were taken for microbiologic and histopathologic analysis. Sera were examined by enzyme-linked immunoabsorbent assay. All specimens were processed in a blind fashion. Chi-square test with Yates' correction was used for statistical analysis. RESULTS: H. pylori was found in 31 of 46 (67%) study patients and in six of 24 (25%) control patients (by microbiologic or histologic techniques) (p less than 0.01). H. pylori was found in all patients with peptic ulcer disease and in 60% of patients without ulcers. No association between H. pylori and any specific gastrointestinal symptom was observed. H. pylori was identified in the fundus as often as in the antrum, although in the antrum the organism was more often associated with histologic gastritis. Compared with histology, serologic assays for IgG and IgA antibodies to H. pylori had sensitivities of 100% and 94%, and specificities of 86% and 76%, respectively. Reexamination of selected specimens without knowledge of their identity revealed that the specificity of serology exceeded 94% while the sensitivity of histologic and microbiologic studies may have been closer to 80%. CONCLUSIONS: H. pylori was more common in dyspeptic patients than in our control subjects undergoing ERCP. Multiple biopsy sites from fundus and antrum are required to exclude infection. Serologies of IgG and IgA were sensitive and specific for H. pylori, suggesting a possible role for non-endoscopic diagnosis of this infection. The frequent association of H. pylori with active inflammation rather than with quiescent gastritis is consistent with a pathologic role of this organism.

Adult↗
PubMed1989

Modulation of the transformed and neoplastic phenotype of rat fibroblasts by MHC-I gene expression.

Transfection of the activated ras oncogene (Ha-ras) into second passage rat embryo fibroblasts can induce the metastatic phenotype, while cotransfection of Ha-ras with the adenovirus type 2 E1a gene (Ad2-E1a) yields cells which are tumorigenic but nonmetastatic in nude mice. Because of the presence in nude mice of natural killer cells and B-lymphocytes, which might account for the different metastatic behavior of single versus double transfectants, we used triple deficient mutants as recipient animals in tumorigenicity assays. These mice carry two additional mutations resulting in the deficiency of natural killer cells and activated B-lymphocytes. We observed that the rat embryo fibroblast transfectants exhibit the same metastatic behavior in nude as well as in triple deficient mice, indicating that natural killer and B-cells are not responsible for the observed difference in metastatic phenotype between Ha-ras and Ha-ras plus Ad2-E1a transfectants. Double transfectants were found to express higher levels of major histocompatibility complex class I genes and the degree of expression appeared to correlate inversely with in vitro and in vivo parameters such as the ability to grow in agar-containing semisolid media and rate of tumor formation in triple deficient mice. Our observations are consistent with the concept that expression of major histocompatibility class I genes may be involved in regulating and modifying cell behavior by mechanisms independent of their role in immune recognition.

Animals↗
PubMed1988

Partial suppression of anchorage-independent growth and tumorigenicity in immunodeficient mice by transfection of the H-2 class I gene H-2Ld into a human colon cancer cell line (HCT).

Many human tumors, particularly those of epithelial origin, appear to express greatly reduced levels of major histocompatibility complex class I antigens on their surface. It has been previously reported that the class I gene H-2Ld, introduced into adenovirus type 12-transformed mouse cells, induces reversal of oncogenesis in immunocompetent BALB/c mice. We have tested the hypothesis that the H-2Ld gene, when transfected into HCT colon cancer cells, may alter their transformed phenotype. Two H-2Ld transfectants, HCT-Ii and HCT-If, were found to exhibit a markedly reduced-to-virtually suppressed ability to form colonies in soft agar in comparison to a transfectant (HCTh) carrying only the neomycin-resistance gene. We also compared the tumorigenicity of HCTh vs. HCT-If cells in two different strains of immunodeficient mice: nude (T-) and triple-deficient mutants (T-, NK-, B-). At 28 days postinjection of 10(7) and 10(6) cells, the size and growth rate of HCT-If tumors were greatly reduced compared to HCTh cells. Therefore, as assayed in immunodeficient animals, expression of the class I H-2Ld gene in HCT cells appears to correlate with partial suppression of the tumorigenic phenotype, suggesting that the expression of a transfected class I gene may by itself alter the phenotype of the recipient cell and that such phenotypic changes may be independent of the immune system.

Animals↗