Evaluation of low dose prostaglandin E1 treatment for ductus dependent congenital heart disease

This study reports our experience with low-dose prostaglandin E₁ (PGE₁) treatment of 91 newborns with ductus dependent congenital heart disease (CHD). PGE₁ efficacy, side-effects as well as the cardiovascular and respiratory profile of the patients were analysed. PGE₁ doses > 0.02 g/kg per minute were used for only 5.3% of the total 23 656 h of treatment. The mean systolic blood pressures did not differ from the normal mean for patients with cyanotic CHD, while the diastolic values were lowered. Respiratory support was required only during 13.7% of the total treatment time. Apnoeas occurred in 21 (38%) of the 55 spontaneously breathing infants, who all had a cyanotic CHD. The incidence of apnoeas was lower during treatment with doses < 0.01 g/kg per minute.     

Enzyme studies in GM2 gangliosidiosis,and their application in prenatal diagnosis

Assay of hexosaminidase A and B enzymes in four cases with developmental regression and cherry red spot on fundus examination confirmed that three cases had Tay-Sachs disease, and one case had Sandhoff disease. Prenatal diagnosis was carried out by hexosaminidase enzyme assay in amniotic fluid and cells in one family, and chorionic villus sample in the second family. The fetus was diagnosed to be unaffected in one, and affected in the other family. Assay of hexosaminidase A and B is useful for specific diagnosis of GM₂ gangliosidosis, and for prenatal diagnosis to reduce the burden of these disorders.     

Vitamin A status of socio-economically backward children

A comprehensive survey was carried out to asses the Vitamin A status of pre-school (0–6 yrs.) and school age (6–12 yrs.) children of socio-economically backward families from slums of Bombay and its suburbs. The Vitamin A, protein, calories and iron from the rice and dal based diet was found to be below recommended dietary allowances (RDA). Among the 1956 children surveyed 20% of the children showed low (<20 μg/dl) serum vitamin A levels. 4.8% of the children were suffering from one or the other signs of Vitamin A deficiency. Rose Bengal stain test (RBST) and conjuctival impression cytology (CIC) indicted the signs of mild conjuctival xerosis and of early epithelial changes which were correlated with serum vitamin A levels. Serum iron, PCV, Hb and RBC levels were below normal. The anthropometric measurements of these children were below 50th percentile of Indian Council of Medical Research (ICMR) standards. Due to lack of proper nutrition, the overall growth of children is either retarded or not upto the standard levels as was noted in majority of the children.     

Pax-1 in the development of the cervico-occipital transitional zone

The Pax-1 gene has been found to play an important role in the development of the vertebral column. The cervico-occipital transitional zone is a specialized region of the vertebral column, and malformations of this region have frequently been described in humans. The exact embryonic border between head and trunk is a matter of controversy. In order to determine a possible role of Pax-1 in the development of the cervico-occipital transitional zone we studied the expression of this gene in a series of quail embryos and murine fetuses with in situ hybridization and immunohistochemistry. Pax-1 is expressed in all somites of the embryo, including the first five occipital ones. During embryonic days 3–5 the gene is down-regulated in the caudal direction within the first five somites, whereas more caudally Pax-1 is strongly expressed in the cells of the perinotochordal tube. In 5-day-old quail embryos, the cartilaginous anlage of the basioccipital bone has developed and there is no more expression of Pax-1 in this region. The fusion of the dens axis with the body of the axis also coincides with switching off of the Pax-1 gene. More caudally, the gene is continuously expressed in the intervertebral discs of murine embryos and therefore seems to be important for the process of resegmentation. Quail embryos do not possess permanent intervertebral discs. Hyper- or hyposegmentation defects may be explained by an over- or under-expression of Pax-1 during development. We also reinvestigated the border between the head and trunk in chick embryos by performing homotopical grafting experiments of the 5^th somite between chick and quail embryos. Grafted quail cells formed mainly the caudal end of the basioccipital bone. They were also located in the cranial half of the ventral atlantic arch, and only a few cells were found in the tip of the dens axis.     

Tumor-associated lymphocytes (TAL) are competent to produce higher levels of cytokines in neoplastic pleural and peritoneal effusions than those found in sera and are able to release into culture higher levels of IL-2 and IL-6 than those released by PBMC

This work was designed to study the proliferative response of tumor-associated lymphocytes (TAL) from neoplastic effusions against autologous tumor cells and the immunophenotype pattern of TAL from neoplastic effusions and that of PBMC of the same patients. We also compared the serum levels of the cytokines interleukin (IL) 1, 2 and 6, tumor necrosis factor- (TNF) and soluble IL-2 receptor (sIL-2R) with those present in neoplastic effusions of the same patients. Moreover, we examined the ability of TAL and peripheral blood mononuclear cells (PBMC) to produce and release the cytokines and sIL-2R and to express membrane CD25 following their stimulation with phytohemagglutinin (PHA) in vitro. Finally, we compared the cytokines/sIL-2R production and membrane CD25 expression by PHA-stimulated PBMC of the patients with neoplastic effusions with a series of 90 cancer patients without neoplastic effusions and 20 normal healthy subjects. Thirteen neoplastic pleural and eight peritoneal effusions were collected from 11 patients with primary lung cancer, 7 with primary epithelial ovarian cancer, 1 with breast cancer, 1 with pleural mesothelioma, and 1 with pancreatic cancer. The proliferative response of TAL from neoplastic effusions against autologous tumor cells was lower than the response to PHA, IL-2, and anti-CD3, but significant. The percentage distribution of CD3⁺ and CD8⁺ lymphocyte subpopulations was higher in peritoneal than in pleural effusions, while the CD16⁺ subset was higher in pleural than in peritoneal effusions. The percentage distribution of CD16⁺ was significantly lower in pleural effusions than in PBMC of patients with pleural effusions. The CD39 antigen was higher on TAL from peritoneal effusions than on PBMC of the same patients. The levels of IL-1 and sIL-2R in peritoneal effusions did not differ from those measured in the sera of the same patients, while the levels of IL-2, IL-6, and TNF were higher in the peritoneal effusions. The levels of IL-2, IL-6, TNF, and sIL-2R, but not IL-1, in pleural effusions were significantly higher than those found in the sera of the same patients. The amounts of IL-2 and IL-6 produced by TAL were generally higher than those released by PBMC. The secretion of cytokines IL-1, IL-2, and sIL2R by PHA-stimulated PBMC was lower, but IL-1 and IL-6 secretion was higher in cancer patients with neoplastic effusions than in either cancer patients without neoplastic effusions or normal subjects. The CD25 expression on PHA-stimulated PBMC derived from cancer patients with neoplastic effusions was in the same range as that of cancer patients without neoplastic effusions and normal subjects. These findings suggest that TAL may be able to produce cytokines and may be amenable to immune manipulation.Abbreviations FITC Fluorescein-isothiocyanate - IL Interleukin - mAb Monoclonal antibody - MHC Major histocompatibility complex - NK Natural killer - PBMC Peripheral blood mononuclear cells - PHA Phytohemagglutinin - TAL Tumor-associated lymphocytes - TIL Tumor-infiltrating lymphocytes - TNF Tumor necrosis factor- - sIL-2R Soluble interleukin-2 receptor     

Mapping of murine YACs containing the genesCea2 andCea4 after B1-PCR amplification and FISH-analysis

PCR with primers specific for the murine B1 consensus sequence allows amplification of DNA from murine sources. We have used B1-PCR for amplifying yeast artificial chromosome (YAC) DNA which can be used to localize single YACs by fluorescencein situ hybridization. The genes for the pregnancy-specific glycoproteins Cea2 and Cea4, both belonging to the large carcinoembryonic antigen gene family, were localized by chromosomalin situ suppression hybridization of three YAC clones to murine chromosome 7A2-A3. This was facilitated by the use of the mouse lymphoma cell line WMP/WMP which contains nine pairs of Robertsonian fusion chromosomes.     

Selective localization of gelatinase A,an enzyme degrading β-amyloid protein,in white matter microglia and in Schwann cells

Gelatinase A is an enzyme capable of cleaving soluble -amyloid protein (AP), and may function as an -secretase to produce secretory forms of amyloid precursor protein. We examined gelatinase A immunoreactivity in the brains and posterior roots of neurologically normal, lacunar stroke, Alzheimer disease (AD), amyotrophic lateral sclerosis, progressive supranuclear palsy and myasthenia gravis cases. The gelatinase A antibody stained only microglial cells in the white matter in all the brain tissues. In AD brain, the reactive microglia located in the center of classical senile plaques, as well as in other microglial cells in the gray matter, showed no immunoreactivity. Gelatinase A in white matter microglial cells may play a role in preventing local deposition of AP. In the posterior root, Schwann cells had positive immunoreactivity. As with other metalloproteases, gelatinase A in Schwann cells may play an antiproliferative role.     

AMPA receptors shape Ca2+ responses in cortical oligodendrocyte progenitors and CG-4 cells

Intracellular calcium signals triggered by glutamate receptor activation were studied in primary cortical oligodendrocyte lineage cells and in the oligodendrocyte cell line CG-4. Glutamate, kainate, and AMPA (30-300 μM) increased [Ca ²⁺]_i in both types of cells at the stage of oligodendrocyte progenitors (O-2A; GD3⁺) or pro-oligodendroblasts (04⁺). The peak amplitude of Ca²⁺ responses to glutamate receptor agonists was significantly larger in cortical cells. In CG-4 and in cortical cells, the majority (more than 90%) of bipolar GD3⁺ or multipolar 04⁺ cells responded to kamate. In all the cells analyzed, kainate was more efficacious than AMPA and glutamate. The percentage of bipolar or multipolar cells responding to glutamate was significantly lower in the CG-4 cell line than in primary cultures. Cellular responses typical of metabotropic glutamate receptor activation were observed in 20% of the cortical O-2A progenitors, but in none of the CG-4 cells. The AMPA-selective antagonist GYKI 52466 blocked kainate-induced Ca²⁺ responses in cortical O-2A cells. The selective AMPA receptor modulator cyclothiazide (30 μM) greatly potentiated the effects of AMPA (30-100 μM) on [Ca ²⁺]_i in cortical and CG-4 cells. Our findings indicate that Ca²⁺ responses in cells of the oligodendrocyte lineage are primarily shaped by functional AMPA receptors. © 1995 Wiley-Liss, Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.

     

Shiva-1: in vitro and in vivo tests of the effects of a novel,synthetic, lytic peptide on ocular cells

An investigation was undertaken to determine the toxicity of an intravitreal injection of a novel peptide drug, Shiva-1, in rabbits. The drug, a synthetic peptide modeled after lytic peptides secreted by certain insects, has antiproliferative and antibacterial properties. Initial in vitro experiments showed that the drug, at a concentration of 100 M, was toxic to both Y-79 retinoblastoma cells and human retinal pigment epithelial cells. A wide range of doses (6–1200 g) was injected into the rabbit vitreous in an attempt to determine the maximum tolerated dose. Retinal toxicity was evaluated clinically, by electroretinography, and by light microscopy. Some localized toxicity was evident at 200 g; all doses of 240 g and above were toxic. While the drug appears to exhibit a narrow range between effective and toxic doses, the results suggest that this and other peptides of similar design merit further investigation for the treatment of proliferative and infectious diseases of the eye.Supported in part by U.S. Public Health Service grants EY07541 and EY02377 from the National Eye Institute, the National Institutes of Health Services, Bethesda, MD, USA     

Evidence for the involvement of the 5-HT1A receptor in CCK induced satiety in rats

The present study was designed to examine possible interactions between exogenous CCK and the 5-HT_1A receptor subtype mediated serotonergic effects on feeding in rats. The somatodendritic 5-HT_1A receptor agonist 8-OH-DPAT (0.32 mg/kg sc) evoked feeding in freely feeding rats. This effect was attenuated by treatment with CCK-8 (1, 5 and 25 g/kg ip). In food deprived rats, CCK-8 (40 g/kg ip) significantly reduced the size of a test meal. Treatment with the 5-HT_1A receptor antagonist WAY-100135 (10 mg/kg ip) antagonized this anorectic effect of CCK-8. WAY-100135 on its own did not affect food intake. These results suggest the involvement of the 5-HT_1A receptor subtype in mediating 5-HT-CCK interactions in the control of food intake in rats.