Vitamin D's role in cell proliferation and differentiation.

Vitamin D has pleiotropic effects that go beyond its traditional role in calcium homeostasis. Hundreds of genes with vitamin D receptor response elements directly or indirectly influence cell cycling and proliferation, differentiation, and apoptosis. Vitamin D compounds also have effects on cell function that are nongenomic.

The mutation rate in PIG-A is normal in patients with paroxysmal nocturnal hemoglobinuria (PNH).

Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by the presence in the patient's hematopoietic system of a large cell population with a mutation in the X-linked PIG-A gene. Although this abnormal cell population is often found to be monoclonal, it is not unusual that 2 or even several PIG-A mutant clones coexist in the same patient. Therefore, it has been suggested that the PIG-A gene may be hypermutable in PNH.

Risk factors for recurrent bleeding and mortality in human immunodeficiency virus infected patients with acute lower GI hemorrhage.

Background: Little is known about lower gastrointestinal (GI) hemorrhage in the human immunodeficiency virus (HIV) infected population. Our aim was to determine the underlying causes, the clinical outcome, and the risk factors for recurrent bleeding and mortality in HIV-infected patients with acute LGIH.

Methods: We reviewed the medical records of consecutive HIV-infected patients with acute lower GI hemorrhage who were evaluated with endoscopy from January 1992 through January 1997 at Bellevue Hospital Center.

Revised transthyretin Ile 122 allele frequency in African-Americans.

The transthyretin (TTR) Ile 122 variant is associated with cardiac amyloidosis in individuals of African descent. To determine the prevalence of the allele encoding TTR Ile 122 in African-Americans, we have used PCR and restriction analysis to test DNA from African-Americans from various geographic areas, and found an allele frequency of 66/3376 (0.020), which is higher than the value we previously reported in a much smaller pilot study.

Patients' and informants' reports of personality traits during and after major depression.

The influence of major depression on patients' and informants' reports of personality traits was examined using the Structured Interview for DSM-III Personality Disorder, both before and after successful antidepressant or placebo treatment (N = 58). According to patients' reports, Cluster A and C traits decreased significantly from pre- to posttreatment, but Cluster B traits were unchanged, excluding an increase in histrionic traits. According to informants' reports, Cluster A and B traits did not change from pre- to posttreatment, but Cluster C traits decreased significantly after treatment, not including passive-aggressive traits.

Acute d-amphetamine challenge in schizophrenia: effects on cerebral glucose utilization and clinical symptomatology.

The effects of d-amphetamine (0.5 mg/kg orally) on regional cerebral glucose utilization were measured with positron emission tomography (PET) in 17 schizophrenics (along with a placebo-control group of an additional six schizophrenic patients). The acute d-amphetamine challenge tended to decrease glucose utilization throughout much of the brain, with a regional effect that was statistically significant in the left temporal cortex.

A specific test for transthyretin 122 (Val----Ile), based on PCR-primer-introduced restriction analysis (PCR-PIRA): confirmation of the gene frequency in blacks.

The variant transthyretin (TTR) allele, TTR (122 Val----Ile), associated with cardiac amyloidosis in blacks, is caused by a G----A transition which destroys a MaeIII site. This variant has previously been detected by PCR around codon 122, followed by MaeIII digestion, but this test is not specific: any of 12 mutations in the MaeIII recognition site, each of which yields a different amino acid change, would also destroy this site. A modification of PCR, termed "PCR-primer-introduced restriction analysis," was used to introduce a new FokI site into the PCR products derived from the variant (122 Ile) but not wild-type (122 Val) allele.

Nifedipine in the treatment of tardive dyskinesia.

There have been several case reports of improvement in tardive dyskinesia (TD) after treatment with calcium-blocking agents. We have conducted prior single-blind (rater-blind) studies of verapamil and diltiazem and found a statistically significant improvement in TD with verapamil, and a small improvement that did not reach statistical improvement after diltiazem treatment. We now report a single-blind (rater-blind) study of a third calcium antagonist, nifedipine, in the treatment of TD.

Mast-cell heterogeneity: functional comparison of purified mouse cutaneous and peritoneal mast cells.

To investigate the functional heterogeneity of mouse mast cells, we extracted and purified cutaneous and peritoneal mast cells from 10- to 18-week-old BALB/c mice and compared their responses to secretagogues. Cutaneous mast cells (CMC) were extracted from mouse ears after digestion with hyaluronidase and collagenase in MEM containing 25% fetal calf serum and purified on a discontinuous Percoll gradient. The histamine content of cells obtained from the 30/40% interface was 1.

A homozygous transthyretin variant associated with senile systemic amyloidosis: evidence for a late-onset disease of genetic etiology.

Senile systemic amyloidosis (SSA) is a late-onset disease characterized by deposition of amyloid fibrils containing transthyretin (TTR). Amino acid sequencing of protein isolated from the amyloid fibrils of a patient with SSA identified TTR containing a position - 122 isoleucine-for-valine substitution. This change led to the prediction of a genomic G-to-A transition, destroying an MaeIII restriction site.

Non-lactogenic effects of growth hormone on growth and insulin-like growth factor-I messenger ribonucleic acid of rat mammary gland.

In contrast to established dogma that PRL is central in mammary development, and GH mimics PRL in affecting growth because of structural similarities, we found that both hGH, which is lactogenic, and rGH, which is non-lactogenic, were significantly more potent than hPRL and rPRL in stimulating mammary growth in rats. Additionally, hGH was more potent than hPRL in increasing mammary IGF-I mRNA content. These data indicate that GH has separate effects on parameters of mammary gland growth, suggesting an independent role for GH in mammary growth.

Platelet-neutrophil interactions. 12S,20- and 5S,12S-dihydroxyeicosapentaenoic acids: two novel neutrophil metabolites from platelet-derived 12S-hydroxyeicosapentaenoic acid.

Dietary marine n-3 polyunsaturated fatty acids have demonstrated an antiinflammatory potential in epidemiologic and intervention studies in humans. Proposed mechanisms, involving only leukocytes, fall short of explaining this potential completely. Enriched by dietary means with eicosapentaenoic acid (EPA), stimulated human platelets release substantial amounts of eicosapentaenoic acid and 12S-hydroxyeicosapentaenoic acid (12S-HEPE) in addition to 12S-hydroxyeicosatetraenoic acid (12S-HETE) derived from arachidonic acid.

Potentiation of the depressant effects of lysophosphatidylcholine on contractile properties of cultured cardiac myocytes by acidosis and superoxide radical.

Lysophosphatidylcholine (LPC) accumulates in the heart during myocardial ischemia. This amphiphile accelerates Ca++ flux in cardiac myocytes and may mediate ischemic cell injury. In the present study, we evaluated the effects of LPC on the contractility of cultured neonatal rat heart cells.

Scrotal island flap urethroplasty in the management of bulbar urethral strictures.

We describe our experience with 20 patients undergoing 1-stage scrotal island flap urethroplasty for severe bulbomembranous stricture disease. While 16 patients achieved satisfactory results, 4 required revision for recurrent stricture, diverticulum or fistula. Use of hairless skin and aggressive tailoring of the flap are stressed to avoid the common complications of diverticulum, hair ball and stone formation.

Albumin redirects platelet eicosanoid metabolism toward 12(S)-hydroxyeicosatetraenoic acid.

Albumin is a major determinant of eicosanoid formation, affecting autacoids important in cell-cell interactions. We delineated three mechanisms by which albumin controlled platelet eicosanoid formation: 1) Albumin diverted free arachidonate toward 12-lipoxygenation. 2) Albumin enhanced release of arachidonate from phospholipids.

Lymphoma in a black patient with actinic reticuloid treated with PUVA: possible etiologic considerations.

A 47-year-old black man with a chronic photocontact dermatitis that evolved into actinic reticuloid was treated with systemically administered PUVA for 15 months. Subsequently an isolated nodule of non-mycosis fungoides T cell lymphoma developed. The use of PUVA may have predisposed this patient to the development of a frank malignancy.

Ethical aspects in the care of patients with AIDS.

Over 91,000 cases of AIDS have been reported in United States, and it has been estimated that more than 1 million individuals are currently infected by the human immunodeficiency virus (HIV). The disease is growing most rapidly among intravenous drug abusers and minority patients. This accentuates some medical and ethical problems.

Prognosis of patients with AIDS requiring intensive care.

The Acute Physiology and Chronic Health Evaluation (APACHE) II classification, a measure of severity of illness in patients requiring intensive care, was devised before the rapid expansion of the acquired immunodeficiency syndrome (AIDS) epidemic. To determine the applicability of the APACHE II system to AIDS, we related observed in-hospital death rates to those predicted by APACHE II in 83 patients with AIDS. In a control group of patients without AIDS (n = 166) mean predicted and observed death rates (34.