Search PubMed⌕ Search

Biomedical subjects

F R Weiner

Publications and source records attributed to F R Weiner.

25 records · Page 2Linked to original sources
PubMed1987

Transcriptional and posttranscriptional effects of dexamethasone on albumin and procollagen messenger RNAs in murine schistosomiasis.

We have previously shown that dexamethasone increases albumin mRNA and decreases procollagen steady-state mRNA levels in rat hepatocyte cultures. These studies were extended by evaluating an in vivo model of fibrogenesis (murine schistosomiasis) and by determining a more precise level of gene expression responsible for these changes. Control mice and litter mates infected with Schistosomiasis mansoni were evaluated at 8 weeks postinfection when the livers of the infected mice had become fibrotic and their serum albumin levels significantly decreased. The addition of 4 micrograms/mL dexamethasone to the drinking water of half of the infected mice led to a 75% decrease in the liver collagen content as determined by high-performance liquid chromatography. RNA was extracted from the livers of mice under three conditions: control and infected +/- dexamethasone. This RNA was then hybridized with cDNA probes to determine steady-state levels of specific mRNAs. In the infected mice, albumin mRNA levels were decreased compared to control; however, infected mice treated with dexamethasone increased their albumin mRNA content by 3-fold at 8 weeks. Types I and IV procollagen steady-state mRNA levels in infected mice were increased compared to control while dexamethasone suppressed the mRNA level of collagen in infected mice by 50%. The level of gene expression responsible for these steady-state changes was evaluated by nuclear run-on analysis. While the effect of schistosomiasis on these genes was primarily at a transcriptional level, dexamethasone exerted its effect on different genes in the injured liver by diverse mechanisms, i.e., decreasing collagen synthesis at a transcriptional level and increasing albumin by posttranscriptional mechanisms.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Molecular studies of ceruloplasmin deficiency in Wilson's disease.

Deficiency of serum ceruloplasmin is a characteristic biochemical abnormality of Wilson's disease, although the mechanism of this finding is unknown. Ceruloplasmin messenger RNA (mRNA) levels were therefore examined in five patients with Wilson's disease and five controls with other types of hepatic disease. Northern and dot blot hybridizations showed that detectable ceruloplasmin mRNA was present in all of the patients with Wilson's disease, including one patient with no detectable serum ceruloplasmin. However, the ceruloplasmin mRNA levels in the Wilson's disease patients were only 33% that of controls (P less than 0.001). In contrast, albumin mRNA levels in the Wilson's disease patients averaged 161% that of controls. In an attempt to better delineate the level of gene expression responsible for this decrease in ceruloplasmin mRNA, the nuclear run-on assay was used to analyze transcriptional rates. The amount of ceruloplasmin gene transcription in four Wilson's patients was decreased to 44% that of three controls. These results indicate that the diminished serum ceruloplasmin levels in patients with Wilson's disease are due at least in part to a decrease in ceruloplasmin gene transcription.

Ceruloplasmin↗
PubMed1986

Transcriptional switch from albumin to alpha-fetoprotein and changes in transcription of other genes during carbon tetrachloride induced liver regeneration.

During liver regeneration induced by CCl4 administration to rats, changes in the relative transcription rates of albumin and alpha-fetoprotein genes have been measured in conjunction with other liver-specific and general cellular function genes. Within 24 h following CCl4 administration, albumin gene transcription decreases by 85%, whereas alpha-fetoprotein transcription increases from undetectable levels to 50% of that observed for albumin. These changes precede maximal [3H]thymidine incorporation into DNA which peaks at 48 h. Other genes related to liver-specific functions, such as ligandin, alpha 1-antitrypsin, and cytochrome P-450's, as well as general cellular genes pro alpha 1- and pro alpha 2-collagen, beta-actin, and alpha-tubulin, respond in kinetic patterns often distinct from each other and from albumin and alpha-fetoprotein. Changes in the steady-state levels of albumin and alpha-fetoprotein mRNA correlate with changes in transcription, but there is a lag in alpha-fetoprotein mRNA accumulation, which peaks at 72 h following CCl4 administration. These studies indicate that reciprocal changes in albumin and alpha-fetoprotein gene transcription occur during CCl4-induced liver regeneration, leading to changes in the level of these specific mRNAs. These changes precede DNA synthesis and would appear to represent an alteration in differentiated function of hepatocytes in conjunction with the liver regenerative process.

Actins↗
PubMed1972

Emergency medical transportation. A survey of California ambulance operations.

The most urgent recommendation expressed by physicians, Red Cross officials, ambulance operators and others polled in this ambulance survey was to make much more emergency medical care training available to ambulance personnel. Very few sick and injured receive first aid before an ambulance arrives. Therefore there is also an urgent need to train and motivate the public to provide first aid at the scene of the emergency. Urban ambulances usually respond within 10 minutes, but often rural ambulances take more than 30 minutes to reach an emergency. It is during this interim that lives which could be saved by prompt first aid are lost. Little use has been made of aircraft as emergency ambulances; in 1968, only one emergency trip in 1500 was made by helicopter. Also, California has fewer ambulances which make fewer emergency trips on a population basis than the country at large. Communications at all levels need attention. Seventy-eight percent of the ambulance operations serving the public are not listed among the emergency numbers on the inside front page of telephone directories. Less than ten percent of ambulances have direct radio communication with hospitals. In California most ambulance services are commercially operated and there are formidable financial problems which must be solved before these services can be brought into place as a part of the emergency medical care system.

Accidents, Traffic↗
PubMedDate not supplied

Development of molecular hybridization technology to evaluate albumin and procollagen mRNA content in baboons and man.

We have developed the methodology for evaluating the effects of pathophysiological conditions on the molecular mechanisms of hepatic protein synthesis and fibrogenesis in baboons and man. Total RNA was extracted from percutaneous liver biopsies of five baboons who were chronically fed an ethanol-rich liquid diet, their pair-fed controls and from humans with a variety of liver abnormalities. Chronic alcohol administration in baboons with liver fibrosis and normal serum albumin levels increased in vitro protein synthesis as measured by [35S]methionine incorporation, albumin mRNA content and Type I procollagen mRNA content. There was no difference in the beta-actin (a constitutive protein) mRNA content. In humans, serum albumin levels correlated with albumin mRNA content as indicated by the intensity of dot blot hybridization and Type I procollagen mRNA levels correlated with the activity of liver fibrosis. The use of RNA-DNA hybridization to investigate procollagen mRNA from human biopsies appears to be a valuable tool for evaluating the potential for collagen synthesis and the future course of liver disease. Besides the use of RNA-DNA hybridization, we describe other methodologies which are useful in delineating the levels of gene expression responsible for hepatic mRNA regulation in normal liver and disease states in man. The use of molecular techniques to evaluate human liver disease provides an opportunity to develop clinically relevant information while at the same time offering the additional advantage of providing fundamental knowledge about fibrogenesis.

Albumins↗
PubMedDate not supplied

Steroid-induced mesenteric lipomatosis.

A patient undergoing chronic corticosteroid therapy presented with mesenteric lipomatosis that simulated malignant masses. Computerized tomography was instrumental in identifying these apparent tumors as benign fatty deposits. The spectrum of lipomatous abdominal lesions amenable to diagnosis by computerized tomography is reviewed.

Adrenal Cortex Hormones↗