Centrally infused galanin-(1-15) but not galanin-(1-29) reduces the baroreceptor reflex sensitivity in the rat

It has been demonstrated previously that central administration of the N-terminal galanin fragment (1-15) elicits hypertension and tachycardia and antagonizes the hypotensive effect of the parent molecule galanin-(1-29). In order to further clarify the role of galanin in central cardiovascular control, the possible modulation of the baroreceptor reflex by both galanin molecules has been studied. Different groups of rats were injected in the lateral ventricle with subthreshold doses of galanin-(1-15) (0.1 nmol/rat, or 0.3 nmol/rat), with subthreshold doses of galanin-(1-29) (0.1 nmol/rat, and 0.3 nmol/rat) or with an effective dose of galanin-(1-29) (3.0 nmol/rat). The baroreceptor reflex was elicited by intravenous injections of different doses of L-phenylephrine before and after the intraventricular administration of galanin peptides. The changes of the bradycardic responses after galanin peptide injections as well as the modifications of the baroreceptor reflex sensitivity were evaluated. Intraventricular injections of galanin-(1-15) significantly inhibited the reflex bradycardia elicited by intravenous L-phenylephrine and thus decreased the baroreceptor sensitivity. However, neither subthreshold doses of galanin-(1-29) nor its effective dose were able to modulate these cardiovascular responses. From these data it may be suggested that the galanin fragment (1-15) plays a more important role in central cardiovascular regulation than galanin-(1-29), possibly acting on a specific receptor subtype which exclusively recognizes N-terminal fragments of galanin, and exists on cardiovascular areas of the central nervous system.     

Helicobacter pylori in children

Helicobacter pylori is the major cause of antral gastritis in children, however, it is not always associated with symptoms. The exception to this occurs in duodenal ulcer disease with which H. pylori is linked in children albeit less strongly than in adults. Duodenal ulcers do not recur in older children following eradication of H. pylori. The importance of asymptomatic carriage of H. pylori in children, particularly in relation to the duration of this infection and the subsequent development of gastric cancer, remain to be established. Helicobacter pylori is associated with both hypochlorhydria and persistent diarrhoea in children in developing countries, but the significance of this association is still unknown. Although there is no consensus on the optimal regimen for treating H. pylori infection in children, dual therapy with amoxycillin and bismuth subcitrate for 2 weeks followed by monotherapy with bismuth subcitrate for a further 6 weeks will eradicate H. pylori infection in the majority of children. Those who relapse may be treated with a repeat course plus metronidazole for 4 weeks. Compliance with such regimens is a problem and shorter treatment courses that are equally effective in children need to be defined. Similarly, studies are required on the influence of the intrafamilial reservoir of H. pylori infection on relapse after treatment and the need for whole family eradication therapy.     

Adverse effects of calcium binding contrast agents in diagnostic cardiac angiography. A comparison between formulations with and without calcium binding additives

RATIONALE AND OBJECTIVES: The authors compared complications and hemodynamic and electrophysiologic effects of two formulations of diatrizoate, one with additives that bind calcium and one without, in diagnostic cardiac angiography. METHODS: Two hundred twenty-three consecutive low-risk patients alternately received Hypaque 76 (group 1, little calcium binding effect), and MD 76 (group 2, significant calcium binding). Electrocardiographic and hemodynamic changes related to coronary angiography and left ventriculography were measured, and complications requiring treatment were recorded. RESULTS: There were more complications in patients in group 2 than in group 1 (18 versus 8, P = 0.04). Arterial pressure fell more, the QT interval increased more, and the heart rate fell more in group 2 after coronary angiography. CONCLUSIONS: Formulations of diatrizoate that minimize calcium binding are advocated for cardiac angiography when using high osmolality contrast media. The more detrimental effects that calcium binding has on myocardial function and cardiac conduction may lead to the higher incidence of complications.     

The apparent diffusion coefficient of water in gray and white matter of the infant brain

PURPOSE: The purpose was to obtain normal values of the apparent diffusion coefficient (ADC) in the infant brain and to compare ADC maps with T1- and T2-weighted images. METHOD: Diffusion was measured in nine infants with an ECG-gated SE sequence compensated for first-order motion. One axial slice at the basal ganglia level was investigated with the diffusion-encoding gradients in the slice-selection direction. RESULTS: On ADC maps, the corpus callosum and the optic radiations appeared dark before the onset of myelination, and the crus posterior of the internal capsule could be visualized before it appeared on T1- or T2-weighted images. In gray and white matter, the mean ADC ranged from 0.95 x 10(-9) to 1.76 x 10(-9) m2/s. In the frontal and occipital white matter, in the genu corporis callosi, and in the lentiform nucleus, the ADC decreased with increasing age. The cortex/white matter ratio of the ADC increased with age and approached 1 at the age of 30 weeks. CONCLUSION: ADC maps add information to the T1 and T2 images about the size and course of unmyelinated as well as myelinated tracts in the immature brain.     

Comparing functional results one year and ten years after ileal pouch-anal anastomosis for chronic ulcerative colitis

Proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the treatment of choice for most patients with chronic ulcerative colitis. Long-term results, however remain undefined; the major concern is that function may deteriorate. PURPOSE: The aim of this study was to assess functional outcome in a subgroup of patients who have an IPAA for chronic ulcerative colitis for > 10 years. METHODS: Among 1400 IPAA patients, 75 consecutive subjects (31 females and 44 males; median age 31 at operation) were identified who had the procedure prior to 1982. All patients had functional results recorded 1 year and 10 years following ileostomy closure. RESULTS: There were four deaths during the follow-up period; none were pouch related. Two patients refused ileostomy closure. Of the remaining 69 patients, there were 8 (11 percent) failures, leaving 61 subjects available for study. Stool frequency (7 +/- 3, mean +/- SD) remained unchanged. Of the 50 subjects with initially excellent daytime continence, 39 (78 percent) remained the same, 10 (20 percent) developed minor incontinence, and 1 developed poor control after 10 years. Four of 10 subjects (40 percent) with initial minor daytime incontinence remained unchanged, 4 (40 percent) improved, and 2 (20 percent) worsened. The one subject with poor control at one year was unchanged. Nocturnal fecal spotting increased over the 10-year period but not significantly (38 percent vs. 52 percent; P = 0.08). CONCLUSIONS: After IPAA, functional results in terms of stool frequency and rate of fecal incontinence did not deteriorate with time.     

Environment and health: an analysis of intra-urban differentials in the city of S?o Paulo, Brazil

A field study undertaken in the city of S. Paulo is presented as part of the project Environment and Health in Developing Countries: An Analysis of Intra-Urban Differentials Using Existing Data financed by the Ministry of Foreign Affairs of the United Kingdom with academic support from the London School of Hygiene and Tropical Medicine (LSHTM). The research aim was to fill in the gaps in the information needed to establish associations between mortality, urbanization and the environment. Statistics were produced by means of existing data collected by city departments, research carried out by universities and census data. Data quality was assessed taking into consideration data coverage, accuracy, and sensibility to pinpoint deprived areas in the city of S. Paulo. Socioeconomic data were used to create a composite index for districts and subdistrict in order to form four socioeconomic zones. Mortality differentials between the zones by five broad age groups (0-4, 5-14, 15-44, 45-64 e 65+) and four ICD chapters (circulatory, respiratory, infectious and parasitic and external causes) are presented. The zoning used showed that 43.8% of S. Paulo residents live in areas under the worst socioeconomic conditions. Health data demonstrated that people living in this areas had higher rates of mortality then those living in the areas with the best conditions. Finally, excess mortality data are analyzed and suggested as a good method for allocating health resources.     

Chain length of the polylysine in receptor-targeted gene transfer complexes affects duration of reporter gene expression both in vitro and in vivo

Complexes composed of peptide ligand for the serpin enzyme complex receptor covalently coupled to poly-L-lysine condensed by charge interaction with plasmid DNA direct gene transfer into receptor bearing cells. We compared intensity and duration of reporter gene expression in vitro and in vivo from serpin-enzyme receptor-directed gene transfer complexes prepared with poly-L-lysine of different chain lengths. When substituted with linker and ligand to comparable extents, DNA complexes containing short chain poly-L-lysine were larger and gave higher peak expression but significantly shorter duration of expression than those containing long chain poly-L-lysine. Both peak expression and duration of expression exceeded that observed with Lipofectin. Neither naked DNA nor DNA complexed with unsubstituted polylysine was effective in gene transfer. For in vivo experiments, complexes containing optimal ligand and degree of substitution (based on in vitro data, peptide C105Y, 11 ligands/plasmid DNA molecule) were prepared with either short chain or long chain polylysine and a beta-galactosidase expression plasmid. Following injection into the tail veins of mice, longer chain complexes gave significantly higher expression of reporter gene in lung and spleen that lasted for a significantly longer period of time than the shorter chain complexes. The short chain poly-L-lysine-DNA complexes were larger in diameter, as assessed by electron microscopy or atomic force microscopy, and gave less protection against DNase digestion in vitro than longer chain complexes. Thus, for gene transfer complexes directed at the serpin enzyme complex receptor, longer chain poly-L-lysine gave a much longer duration of expression both in vitro and in vivo. We speculate that this may be due to protection against degradation afforded the plasmid DNA by the tighter compaction produced by long chain poly-L-lysine.     

IFN-tau: a novel subtype I IFN1. Structural characteristics, non-ubiquitous expression, structure-function relationships, a pregnancy hormonal embryonic signal and cross-species therapeutic potentialities

IFN-tau (IFN-tau) constitutes a new class of type I IFN which is not virus-inducible, unlike IFN-alpha and IFN-beta, but is constitutively produced by the trophectoderm of the ruminant conceptus during a very short period in early pregnancy. It plays a pivotal role in the mechanisms of maternal recognition of pregnancy in ruminants and it displays high antiviral and antiproliferative activities across species with a prominent lack of cytotoxicity at high concentrations in vitro in cell culture and possibly in vivo. It exhibits high antiretroviral activity against HIV and exhibits immunosuppressive activity in a multiple sclerosis model and reduces embryo and fetal mortality by stimulation of IL-10 production. In this review all the biochemical and para-hormonal properties of this novel IFN-tau are described in detail: structural characteristics of proteins and genes, trophoblast expression, regulation of its expression, structure of its gene promoter, its absence in human species and in non-ruminant animals, the evolution of the IFN-tau genes, its structure-function relationships with its three-dimensional structure, structural localization of biological activities, its lack of cytotoxicity and its receptor. Surprisingly, for an IFN, IFN-tau is also a pregnancy-embryonic signal with paracrine antiluteolytic activity. In order to maintain luteal progesterone secretion, IFN-tau inhibits PGF-2alpha pulsatile secretion and oxytocin uterine receptivity in early pregnancy. It is believed to suppress pulsatile release of endometrial PGF-2alpha by preventing oxytocin and estrogen receptor expression. Additionally, it directly regulates prostaglandin metabolism and possibly the PGE:PGF-2alpha ratio.