BFU-E colony growth in response to hydroxyurea: correlation between in vitro and in vivo fetal hemoglobin induction.

Patients with sickle-cell anemia treated with hydroxyurea may have significant reduction in frequency and severity of pain episodes. However, previous clinical trials show a variable response to hydroxyurea. Criteria which can be used to select patients who are likely to respond to hydroxyurea treatment would be useful.

Globin gene silencing in primary erythroid cultures. An inhibitory role for interleukin-6.

There are numerous similarities between the erythroid and megakaryocytic lineages which suggest that commitment to either lineage occurs relatively late in hematopoiesis. Commitment toward megakaryocyte development requires obligatory silencing of erythroid-specific genes. Therefore, we investigated the effects of interleukin-6, a known inducer of thrombocyte production, on globin gene expression during erythroid differentiation.

Reduced asthma symptoms with n-3 fatty acid ingestion are related to 5-series leukotriene production.

Asthma may respond to dietary modification, thereby reducing the need for pharmacologic agents. This study determined the effectiveness of n-3 polyunsaturated fatty acid (PUFA) ingestion in ameliorating methacholine-induced respiratory distress in an asthmatic population. The ability of urinary leukotriene excretion to predict efficacy of n-3 PUFA ingestion was assessed.

Antibody reactive with Actinobacillus actinomycetemcomitans leukotoxin in early-onset periodontitis patients.

The objective of this study was to determine whether a relationship exists between antibody reactive with the Actinobacillus actinomycetemcomitans leukotoxin and the severity of periodontal disease. Serum concentrations of antibody reactive with the leukotoxin were determined for 119 early-onset periodontitis patients and 59 non-periodontitis subjects using limiting dilution analysis on Western blots. Immunoglobulin G (IgG) antibody reactive with the A.

In vivo search for butyrate responsive sequences using transgenic mice carrying A gamma gene promoter mutants.

We describe an in vivo approach, in transgenic mice, aimed to identify promoter elements responsible for the induction of gamma globin expression by butyrate. Transgenic lines carrying human A gamma gene promoter truncations at position -141, -201, -382, and -730 A gamma were treated with alpha amino butyric acid (alpha ABA), and effects on gamma globin expression were analyzed at the messenger RNA level. No induction of gamma gene expression was observed in animals carrying promoters truncated at positions -141, -201, or -382 A gamma, suggesting either that butyrate response elements (BRE) are not located in the proximal gamma gene promoter or, if they were, they require the cooperation of upstream sequences for gamma gene induction.

Resident education in laparoscopic cholecystectomy.

Background: Resident education in laparoscopic cholecystectomy (LC) was studied in a retrospective analysis of consecutive cases performed at two academic institutions with different educational approaches.

Methods: Each procedure was performed by a resident as operating surgeon under the direct guidance of one of a small, constant group of LC-certified attendings acting as first assistant. In group I (n = 48), residents acquired LC skills by graded exposure and surgical responsibility similar to their training in other general surgical procedures.

alpha-Amino butyric acid cannot reactivate the silenced gamma gene of the beta locus YAC transgenic mouse.

Butyric acid, a naturally occurring fatty acid, has been shown to increase fetal hemoglobin in BFUe cultures, in primates, and in patients with beta chain hemoglobinopathies. The precise mechanism of gamma gene induction by butyrate is unknown. Butyrate may induce fetal hemoglobin production in vivo by reactivation of silenced gamma globin genes, by inhibiting the silencing of gamma genes, or by both mechanisms.

Follow-up of patients with breast cancer.

Routine, thorough history and physical examinations are the mainstay of follow-up for patients with breast cancer. Yearly mammography of the contralateral breast in all patients is important, as is more frequent radiologic surveys of the ipsilateral breast in patients who had breast-conserving therapy. Frequent chest films and regular bone scans are beneficial only in those patients with advanced disease for improving palliation.

Fetal hemoglobin induction by acetate, a product of butyrate catabolism.

Butyrate induces fetal hemoglobin (HbF) synthesis in cultures of erythroid progenitors, in primates, and in man. The mechanism by which this compound stimulates gamma-globin synthesis is unknown. In the course of butyrate catabolism, beta oxidation by mitochondrial enzymes results in the formation of two acetate molecules from each molecule of butyrate.

Transgenic mouse model of pharmacologic induction of fetal hemoglobin: studies using a new ribonucleotide reductase inhibitor, Didox.

Evaluation of pharmacologic agents that stimulate fetal hemoglobin production has been done mainly in baboons and macaques. We investigated whether results in transgenic mice can predict the stimulation of fetal hemoglobin in primates, by testing gamma globin induction in response to a new ribonucleotide reductase inhibitor, Didox. A transgenic mouse line carrying the human A gamma gene linked to a locus control region cassette was used.

Principles of rehabilitation after chronic tendon injuries.

This article describes a framework for the evaluation, diagnosis, and management of tendon injuries that result from repetitive microtrauma overload. These injuries are commonly called tendinitis injuries, but are more often degenerative lesions. The initial management of acute tendon injuries with rupture is usually quite different than that of chronic injuries, but the functional rehabilitation of the acute injuries can follow the same framework.

Shoulder strength, power, and endurance in college tennis players.

Twenty-four college tennis players were tested for bilateral shoulder internal/external rotation strength on a Cybex 340 isokinetic dynamometer; they were positioned supine with the glenohumeral joint abducted to 90 degrees. Subjects produced significantly (P less than 0.01) more torque in internal rotation at 60 and 300 deg/sec in the dominant arm compared to the nondominant arm.

Intraoperative cholangiography revisited.

The charts of 1351 patients undergoing cholecystectomy at our institutions from 1985 through 1989 were reviewed retrospectively to evaluate the indications for and the success of intraoperative cholangiography. A total of 800 patients underwent intraoperative cholangiography. They were divided into two groups based on the absence (CR-) or presence (CR+) of clinical and/or operative criteria suggestive of the existence of common bile duct stones.

Evolutionary relationships among sulfur- and iron-oxidizing eubacteria.

Some 37 reverse transcriptase, partial 16S rRNA sequences from sulfur- and/or iron-oxidizing eubacteria, including sequences from species of the genera Thiobacillus, Thiothrix, Thiomicrospira, Acidophilium, "Leptospirillum," Thiovulum, and Chlorobium, have been determined. In addition, 16S sequences from a number of unnamed sulfur- and/or iron-oxidizing bacteria from hydrothermal vent sites, from invertebrate-bacterial endosymbioses, and from various mineral recovery operations also have been determined. The majority of sequences place their bacterial donors in one or another of the subdivisions of the Proteobacteria.

Professional careers of 258 graduates of a 'fifth pathway' program.

Two hundred fifty-eight graduates (80%) of a fifth pathway program provided information about their professional careers. Fifty-nine percent practice primary care medicine, 25% are surgeons, and 16% are in support services such as psychiatry and radiology. Fifty-four percent are board certified, many of whom are doubly-board certified and some of whom hold prestigious academic positions.

Pulmonary manifestations of HIV infection in children.

We retrospectively reviewed the spectrum, course, and outcome of pulmonary diseases in 66 children with AIDS, hospitalized between 1982 and 1988, prior to the use of zidovudine. Fifty-two of the 66 (79%) patients developed pulmonary problems. In fifty-two percent of all patients, a pulmonary problem was the first symptom of HIV infection.

Characterization of ribonuclease P from the archaebacterium Sulfolobus solfataricus.

Ribonuclease P is the endonuclease that removes the leader fragments from the 5'-ends of precursor tRNAs. The enzyme isolated from eubacteria contains a catalytic RNA subunit. RNAs also copurify with eukaryotic RNase P, although catalysis by those RNAs has not been demonstrated.

Knowledge of AIDS risk factors in south Bronx minority college students.

Hostos Community College is located in the South Bronx, an epicenter of the AIDS epidemic. The student body is 84% Hispanic and 12% black; Hispanics and blacks account for 70% of AIDS cases among heterosexual adults nationwide and 75% of pediatric cases. We surveyed 1,869 Hostos students to determine their understanding of AIDS risk factors.