Distinct functions of N and C-terminal domains of GreA, an Escherichia coli transcript cleavage factor.

The prokaryotic transcription factors GreA and GreB are involved in the regulation of transcript elongation by RNA polymerase (RNAP). Their known activities include suppression of transcription arrest, enhancement of transcription fidelity, and facilitation of the transition from abortive initiation to productive elongation. Presumably, Gre proteins exert their functions by altering the conformation of the enzyme in ternary elongation complexes (TEC) and inducing the cleavage of nascent RNA.

Is there any evidence for a post-tubal sterilization syndrome?

Objective: To review the literature on menstrual and hormonal changes in women who under go tubal sterilization.

Design: A systematic review through MEDLINE and a literature search identified more than 200 articles in the English literature from which the most relevant were selected for this review.

Result(s): Many authors have investigated the sequelae of female sterilization.

Risk stratification for recurrent tachyarrhythmias in patients with paroxysmal atrial fibrillation and flutter: role of signal averaged electrocardiogram and echocardiography.

The value of signal-averaged P-wave electrocardiogram and echocardiography for predicting recurrent atrial tachyarrhythmias was prospectively investigated in 60 patients presenting with paroxysmal atrial fibrillation or flutter. All patients were followed up for 1 year after restoration of sinus rhythm. A stepwise discriminant function analysis was used to identify variables predicting recurrent atrial tachyarrhythmias.

Promoter specificity determinants of T7 RNA polymerase.

The high specificity of T7 RNA polymerase (RNAP) for its promoter sequence is mediated, in part, by a specificity loop (residues 742-773) that projects into the DNA binding cleft (1). Previous work demonstrated a role for the amino acid residue at position 748 (N748) in this loop in discrimination of the base pairs (bp) at positions -10 and -11 (2). A comparison of the sequences of other phage RNAPs and their promoters suggested additional contacts that might be important in promoter recognition.

Novel glutamate- and GABA-independent synaptic depolarization in granule cells of guinea-pig hippocampus.

1. Dual intracellular recordings of granule cells, hilar interneurons and CA3 pyramidal cells were performed in transverse slices of guinea-pig hippocampus. At resting membrane potential, in the presence of 4-aminopyridine, ionotropic glutamate receptor antagonists and the GABAA receptor antagonist bicuculline, granule cells showed spontaneous, large amplitude depolarizations correlated with synchronous bursting activity of interneurons.

Variable place-cell coupling to a continuously viewed stimulus: evidence that the hippocampus acts as a perceptual system.

A key feature of perception is that the interpretation of a single, continuously available stimulus can change from time to time. This aspect of perception is well illustrated by the use of ambiguous figures that can be seen in two different ways. When people view such a stimulus they almost universally describe what they are seeing as jumping between two states.

Laboratory studies in cross-species lung transplantation.

The lack of sufficient suitable human donor lungs for the many patients requiring pulmonary transplantation as life-saving therapy for end-stage lung diseases has generated extensive interest in cross-species lung transplantation. Ethical concerns and those of animal rights advocates have prompted studies of nonprimate species as potential solid organ donors for humans. This paper provides an overview of some of the laboratory studies of cross-species pulmonary transplantation performed over the past 20 years and focuses, in particular, on more recent work (from our laboratory and others) in the area of porcine-to-primate pulmonary xenotransplantation.

Roles of outward potassium currents in the action potentials of guinea pig ureteral myocytes.

Outward currents of freshly dissociated ureteral myocytes consist mainly of Ca(2+)-activated K+ current (IKCa) and a transient outward current (ITO). No delayed rectifier current was apparent. IKCa is small and nondecaying and fluctuates actively and irregularly.

Differences in prostate and adipose tissue basic fibroblast growth factor: analysis of preliminary results.

Objectives: Basic fibroblast growth factor (bFGF or FGF-2) is mitogenic to human prostate epithelial and stromal cells, and it is reported to be elevated in the serum and urine of patients with various cancers, including prostate cancer. Obesity, with increased body fat, is a risk factor for prostate cancer through unknown mechanisms. Because adipose tissue is a source of FGF-2, we determined the quantity and quality of activity of FGF-2 in omental adipose tissue and compared it with normal and cancerous prostate tissues.

Relationship of visceral adipose tissue and glucose disposal is independent of sex in black NIDDM subjects.

To determine the interrelationship among insulin action, total or regional adiposity, and sex, we measured insulin-mediated glucose disposal by the euglycemic insulin clamp and adipose distribution using computed axial tomography (22 scans) in 32 black men and 20 black women with non-insulin-dependent diabetes mellitus (age 48 +/- 9 and 54 +/- 9 yr, body mass index 26.3 +/- 2.3 and 27.

Characterization of the myosin heavy chains of avian adult fast muscles at the protein and mRNA levels.

High resolution anion-exchange chromatography of myosin subfragment-1 in avian fast muscles revealed five fast heavy chains (I-V) expressed in muscle-specific patterns. Sequence analysis of a unique peptide established that the proteins differed in primary structure and suggested correlation with heavy chain genes identified independently by Robbins and coworkers. The identities of the isoforms and their expression patterns were confirmed at the mRNA level by a reverse-transcription, 5'-anchored PCR procedure.

The recognition potential, word difficulty, and individual reading ability: on using event-related potentials to study perception.

Ten observers detected words in a stream of random letters. The latency of the recognition potential (RP) was less for easier words. This implicated short latency processes in word detection.

Anemia following renal transplantation: erythropoietin response and iron deficiency.

To define the etiology of anemia post-renal transplantation, we assessed hematologic parameters and EPO levels in 38 anemic and 16 non-anemic control renal transplant recipients (RTRs) with varying degrees of allograft function at periods > 3 months post-transplantation. Significant differences between the two groups were found for serum creatinine (Cr) 291.7 +/- 26.

The effect of isoflurane on biochemical changes during and electrophysiological recovery after anoxia in rat hippocampal slices.

It is unclear whether isoflurane protects against neuronal damage. This study examines the extent and mechanism by which isoflurane might affect anoxic neuronal damage. The size of the evoked postsynaptic population spike recorded from the CA 1 pyramidal cell layer of the rat hippocampal slice 60 min after anoxia was compared with its preanoxic, preisoflurane level.

Cardiac binding in experimental heart failure.

Background: Cardiomyoplasty is a potential therapy for heart failure. Its benefits are attributed to systolic augmentation (dynamic cardiomyoplasty) and prevention of cardiac dilatation (static cardiomyoplasty). To evaluate the static component, we used an artificial membrane for cardiac binding in a canine model of heart failure.

Segregated populations of mitral/tufted cells in the accessory olfactory bulb.

The dendritic distribution of mitral/tufted (M/T) cells in the opossum accessory olfactory bulb (AOB) was investigated using intracellular injection of Lucifer yellow and DiI labeling. Lucifer yellow labeling demonstrated that the primary dendrites of M/T cells are restricted to one of the two subregions (anterior or posterior) of the glomerular layer. When DiI was placed in the anterior or posterior subregion of the glomerular layer, virtually all of the labeled cell bodies in the AOB were located in the anterior or posterior part of the M/T cell layer, respectively.

Utility of untimed urinary albumin measurements in assessing albuminuria in black NIDDM subjects.

Objective: To determine the usefulness of an untimed morning urine specimen in screening a black NIDDM population attending an urban diabetes clinic for microalbuminuria.

Research Design And Methods: Untimed morning specimens were provided by 218 black NIDDM subjects. Of the 218 subjects, 123 also provided 24-h urine specimens.

IgE-bearing cells and epsilon-specific mRNA in lymphoid organs of two children with AIDS.

To characterize the cellular basis of IgE responses in HIV-positive (HIV+) children, we obtained central (bone marrow [BM], thymus) and peripheral (Peyer's patches [PP], mesenteric [MLN], and other lymph nodes [OLN], spleen), lymphoid organs from two children with AIDS (females, 2 and 8 years old), and from a non-HIV-infected trauma victim (female, 5 years old) at autopsy. PP were obtained from one of the HIV+ children (2 yr old) and from the non-infected child, but no PP were detected in small intestine of the 8-yr-old HIV+ child. Numbers of lymphocytes bearing surface IgE, CD19, CD3, CD4, and CD8 in lymphoid organs were determined (flow cytometry) and evaluated for expression of epsilon-specific (E) mRNA (RT-PCR).

Multicenter comparison of clotrimazole vaginal tablets, oral metronidazole, and vaginal suppositories containing sulfanilamide, aminacrine hydrochloride, and allantoin in the treatment of symptomatic trichomoniasis.

Background And Objectives: Trichomonas vaginalis is a common vaginal pathogen. Oral metronidazole is the drug of choice for the treatment of trichomoniasis. Oral metronidazole, however, may cause unpleasant side effects and is contraindicated during the first trimester of pregnancy.

Eccrine syringofibroadenoma surrounding a squamous cell carcinoma: a case report.

A 91-year-old man presented with a 9.0 x 7.0 cm exophytic mass on the dorsum of the right foot, surrounded by a scaling hyperkeratotic plaque-like lesion that had been present for many years.

Antiretroviral therapy for pregnant women.

Reproductive-age women constitute an increasing percentage of individuals infected with human immunodeficiency virus. As clinical management issues particular to pregnancy become increasingly common, they are also becoming increasingly complex. With the approval of new antiretroviral agents, monotherapy with zidovudine, although still standard for prevention of mother-to-child transmission of human immunodeficiency virus, has become inadequate therapy for treatment of the mother.