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The article presents information on courses in chemistry orientation. Courses like "Science Orientation," "Survey of Science," or "Introduction to Science," are being presented in an increasing number of colleges in the U.S. Such courses generally include instruction in chemistry, physics, botany, zoology and astronomy. It can hardly be questioned that such college courses in science of a general nature fill a definite need and have a desirable function. In order to retain or increase these advantages, the chemistry unit of an orientation course should have certain definite objectives and the course should be presented in a manner that will easily fulfill these objectives. The course in chemistry orientation is to familiarize all students with the role of chemistry in daily life. Student should be aided in the selection of his major field, by giving him a more intelligent basis of selection.

Background: The tuberculin skin test (TST) is the recommended method for screening for Mycobacterium tuberculosis infection in many countries. We used this technique to assess bacillus Calmette-Guérin (BCG) status and to estimate the current prevalence and annual rate of latent tuberculosis infection in schoolchildren in the Central African Republic., Methods: Two tuberculin units of 0.1 ml purified protein derivative TR23 were injected intradermally into the left forearm of 2710 children attending school in Bangui and Ombella M'Poko. The induration size was interpreted at cut-off points of ≥ 5 mm, ≥ 10 mm and ≥ 15 mm. The annual infection rate was estimated as the average number of infections in the study sample each year between birth and the time of the survey., Results: Overall, there was no reaction to the TST (no induration) in 71.7 % (95 CI, 68.3-75.3 %) of BCG-vaccinated children and 82.9 % (95 CI, 74.1-91.4 %) of non-vaccinated children. The proportions of children who gave a TST reaction above ≥ 10 mm and ≥ 15 mm cut-off was 18.4 % (95 % CI, 16.8-20.1 %) and 8.9 % (95 % CI, 7.8-10.0 %), respectively. The proportions of TST reaction above these cut-offs were 19.6 % (95 % CI, 17.4-21.9 %) and 8.1 % (95 % CI, 6.7-9.6 %), respectively. The annual infection rate was 0.8 % at the cut-off point of ≥ 15 mm., Conclusion: This study provides updated data on rates of tuberculosis infection in the Central African Republic. It is remarkable that most of the children had negative tuberculin reactivity. More studies are required to understand the factors that determine the low tuberculin reactivity in this population.

There is much variation in the implementation of the best available evidence into clinical practice. These gaps between evidence and practice are often a result of multiple individual decisions. When making a decision, there is so much potentially relevant information available, it is impossible to know or process it all (so called 'bounded rationality'). Usually, a limited amount of information is selected to reach a sufficiently satisfactory decision, a process known as satisficing. There are two key processes used in decision making: System 1 and System 2. System 1 involves fast, intuitive decisions; System 2 is a deliberate analytical approach, used to locate information which is not instantly recalled. Human beings unconsciously use System 1 processing whenever possible because it is quicker and requires less effort than System 2. In clinical practice, gaps between evidence and practice can occur when a clinician develops a pattern of knowledge, which is then relied on for decisions using System 1 processing, without the activation of a System 2 check against the best available evidence from high quality research. The processing of information and decision making may be influenced by a number of cognitive biases, of which the decision maker may be unaware. Interventions to encourage appropriate use of System 1 and System 2 processing have been shown to improve clinical decision making. Increased understanding of decision making processes and common sources of error should help clinical decision makers to minimize avoidable mistakes and increase the proportion of decisions that are better., (© 2012 The National Institute for Health & Clinical Excellence. British Journal of Clinical Pharmacology © 2012 The British Pharmacological Society.)

Purpose: A recent genome-wide scan revealed a major susceptibility locus for idiopathic generalized epilepsies (IGEs) in the chromosomal region 8p12 in 32 IGE families without members with juvenile myoclonic epilepsy (JME). This study explored the presence of an IGE locus in the chromosomal region 8p12., Methods: Our study included 176 multiplex families of probands with common IGE syndromes. Parametric and nonparametric multipoint linkage analyses were carried out between the IGE trait and six microsatellite polymorphisms encompassing the putative susceptibility locus. To explore the associated phenotype-genotype relation, two distinct subgroups of families were selected by the presence (n = 64) or absence (n = 112) of a family member with JME. To adjust the phenotypic spectrum toward adolescent-onset IGEs, a third subgroup of 28 families without JME was chosen through an IGE proband with seizure onset at age 10-20 years., Results: Parametric and nonparametric multipoint linkage analyses provided no evidence for linkage between IGE and markers encompassing the putative IGE locus in the chromosomal region 8p12. Furthermore, we found no hint of linkage along the candidate region in any of the three family subgroups., Conclusions: We failed to provide evidence for a major IGE locus in the chromosomal region 8p12. On the contrary, these parametric linkage results provide strong evidence against linkage across the candidate region under a broad range of genetic models. If there is a susceptibility locus for IGE in the chromosomal region 8p12, then the size of the effect or the proportion of linked families is too small to detect linkage in the investigated family sample.

A recent genome-wide scan showed strong evidence for a major locus for common syndromes of idiopathic generalized epilepsy (IGE) at the marker D18S474 on chromosome 18q21.1 (LOD score 4.5/5.2 multipoint/two-point). The present replication study tested the presence of an IGE locus in the chromosomal region 18q21.1. Our linkage study included 130 multiplex families of probands with common IGE syndromes. Eleven microsatellite polymorphisms encompassing a candidate region of 30 cM on either side of the marker D18S474 were genotyped. The two-point homogeneity LOD score for D18S474 showed strong evidence against linkage at the original linkage peak (Z = -18.86 at theta(m = f) = 0.05), assuming a recessive mode of inheritance with 50% penetrance. Multipoint parametric heterogeneity LOD scores < -2 were obtained along the candidate region when proportions of linked families greater than 35% were assumed under recessive inheritance. Furthermore, non-parametric multipoint linkage analyses showed no hint of linkage throughout the candidate region (P > 0.19). Accordingly, we failed to support evidence for a major IGE locus in the chromosomal region 18p11-18q23. If there is a susceptibility locus for IGE in this region then the size of the effect or the proportion of linked families is too small to detect linkage in the investigated family sample., (Copyright 2002 Wiley-Liss, Inc.)

A previous study of 34 nuclear pedigrees segregating juvenile myoclonic epilepsy (JME) gave significant evidence of linkage with heterogeneity to marker loci on chromosome 15q13-14 close to the candidate gene CHRNA7 (Hum. Mol. Genet. 6 (1997) 1329). The aim of this work was to further evaluate the putative aetiological role of CHRNA7 in JME within the 34 families originally described, and to assess the contribution of this locus to a broader phenotype of idiopathic generalised epilepsy (IGE). Multipoint linkage analysis and intrafamilial association studies were performed with microsatellite markers that encompass both CHRNA7 and its partial duplication (CHRFAM7A). A maximum HLOD of 3.45 [alpha=0.58; (Zall=2.88, P=0.0008)] was observed 8 cM distal to D15S1360, a CHRNA7 intragenic marker. Significant exclusion lod scores were obtained across the region in 12 mixed phenotype JME/IGE families. Mutation screening of the CHRNA7 gene (and consequently exons 5-10 of CHRFAM7A) and its putative promoter sequence identified a total of 13 sequence variants across 23 of 34 JME-affected families. Two variants (c.1354G>A and c.1466C>T) are predicted to result in amino acid changes and one (IVS9+5G>A) is predicted to result in aberrant transcript splicing. However, none of the variants alone appeared either necessary or sufficient to cause JME in the families in which they occurred. In conclusion, linkage analyses continue to support the existence of a locus on chromosome 15q13-14 that confers susceptibility to JME but not to a broader IGE phenotype. Causal sequence variants in the positional candidate CHRNA7 have not been identified but the presence of multiple segmental duplications in this region raises the possibility of undetected disease-causing genomic rearrangements.

Genetic factors play a major role in the aetiology of idiopathic generalised epilepsies (IGEs). The present genome scan was designed to identify susceptibility loci that predispose to a spectrum of common IGE syndromes. Our collaborative study included 130 IGE-multiplex families ascertained through a proband with either an idiopathic absence epilepsy or juvenile myoclonic epilepsy, and one or more siblings affected by an IGE trait. In total, 413 microsatellite polymorphisms were genotyped in 617 family members. Non-parametric multipoint linkage analysis, using the GeneHunter program, provided significant evidence for a novel IGE susceptibility locus on chromosome 3q26 (Z(NPL) = 4.19 at D3S3725; P = 0.000017) and suggestive evidence for two IGE loci on chromosome 14q23 (Z(NPL) = 3.28 at D14S63; P = 0.000566), and chromosome 2q36 (Z(NPL) = 2.98 at D2S1371; P = 0.000535). The present linkage findings provide suggestive evidence that at least three genetic factors confer susceptibility to generalised seizures in a broad spectrum of IGE syndromes. The chromosomal segments identified harbour several genes involved in the regulation of neuronal ion influx which are plausible candidates for mutation screening.

The term epilepsy encompasses a heterogeneous group of disorders, with a lifetime cumulative incidence of 3%. Genetic factors are thought to contribute to the aetiology in up to 60% of cases. Various molecular and cellular mechanisms give rise to epilepsy, and epilepsy genes fall into several distinct categories. They include genes in which mutations cause abnormal ion-channel function, disordered brain development, progressive neurodegeneration and disturbances of cerebral energy metabolism. In this review, we have focused on current understanding of the molecular genetic bases of human inherited epilepsies. Particular reference has been given to specific idiopathic epilepsies, neuronal migration disorders (cortical dysgeneses) and the progressive myoclonic epilepsies, and how information about this group of disorders might be used to develop new treatment strategies.

The effect of administering thyrotropin-releasing hormone (TRH) before farrowing on the ability of their newborn piglets to withstand a cold challenge was studied. Sows received intravenous infusions of TRH (5 microg kg(-1); TRH group) or physiological saline (0.9% NaCl; control group) from day 105 of gestation until farrowing. The plasma concentrations of thyroxine and triiodothyronine increased in sows treated with TRH. There were no differences in thyroxine and triiodothyronine between pigs born to sows in the TRH group and those of the control group. The rectal temperature of piglets born to TRH-treated sows decreased less than that of piglets born to controls as a consequence of a 1-hour cold challenge. Piglets born to sows in the TRH group had higher body weights at birth, and by day 28 they were an average 600 g heavier than those born to sows in the control group. Summarizing, prenatal maternal treatment with TRH appears to increase piglets' resistance to cold as well as to have beneficial effects on birth and weaning weights.

Background: Microwave (MW) radiation is being increasingly used as a source of heat supplementation during early postnatal development of pigs. Although MW radiation does not cause deleterious physiological effects, no specific information exists regarding its impact on immune cells such as macrophages. Pulmonary intravascular macrophages (PIMs) are emerging as important inflammatory cells due to their endocytic and secretory potential. An in vivo study was conducted to evaluate the effects of infrared, and low and high power MW radiation on the PIMs of pigs., Methods: Pigs were exposed to infrared (IR), low MW (LMW; 6.1mW cm-2), and high MW (HMW; 11.4mW cm-2) radiation at 915 MHz (n = 2 for each treatment) for 24 hr. The controls (n = 2) were exposed to natural light for the same period of time. Lung tissues were processed for ultrastructural examination and acid phosphatase (AcPase) cytochemistry. In addition, rough endoplasmic reticulum (RER) as a fraction of cytosol of the PIMs was counted., Results: Ultrastructural and numerical data suggested enhanced secretory activity in the PIMs of LMW-treated pigs as indicated by the increased RER:cytoplasm ratio, prominent Golgi complex profiles, and accumulation of secretory vesicles in conjunction with microtubules as compared with the control, IR, and HMW-exposed pigs. High MW treatment induced some damage to pulmonary interstitium as deduced from the presence of extracellular AcPase precipitates and disrupted collagen matrix. Intracellular globules were noticed in the PIMs of IR and LMW-treated pigs but not in the control and HMW-radiated animals., Conclusions: Elaboration of structural signs of secretory activity in the PIMs by LMW radiation in the absence of pulmonary pathological changes indicates its potential for cell activation in addition to the already established role of LMW in heat supplementation. This activation could be due to either increased core body temperature or initiation of intracellular signaling by the LMW radiation. This study also shows that the HMW radiation is capable of inducing pathology in the form of changes in the pulmonary interstitial matrix and may not be a good source of supplementary heat.

Twelve pregnant primiparous sows were catheterized on day 102 of gestation and randomly allocated to receive ACTH (days 112-113 of gestation [2d], days 105-parturition [10d]) or saline. At parturition the 3rd, 4th, 6th and 7th piglet born alive were sacrificed either at birth or at 6 h. The later group was fed bovine colostrum through a stomach tube at 30 min, 2 and 4 h of life. Following sacrifice, the small intestine of each piglet was excised, extended and measured. Piglets from sows in the 2d group tended to be heavier with longer small intestines than either the control or 10d groups. When the small intestine length was expressed as a function of body weight, the 10d group had the greatest ratio, suggesting that the pre-parturition maintenance of elevated cortisol levels either enhanced small intestine growth or attenuated overall weight gain. Two types of enterocyte granules were described at the level of the electron microscope: granular and opaque. Opaque granules from piglets born to sows in the 2d treatment group had both a lower volume fraction and were fewer per unit area when compared to those of either the saline or 10d treatments. The process of macromolecule uptake from the intestinal lumen appeared to have been interfered with as a result of an acute prenatal stimulation with ACTH. The above results suggest that in piglets, the level of circulating cortisol differentially controls the processes of IgG absorption, enterocyte replacement and small intestine growth through separate mechanisms. Further, these processes can be manipulated in the prenatal piglet.

As the focus of UK health care moves towards the achievement of health gain, information on health outcomes is required by health care commissioners and providers in order to bring about improved patient outcomes. The information required includes health care activity and population data, and textual and bibliographic information to identify published outcomes studies and current health outcomes activities. A survey of enquiries received by the UK Clearing House on Health Outcomes was undertaken to ascertain the nature and level of enquiries, and their geographical and organizational origins in the UK. The study cannot claim to be a comprehensive review of the demand for and use of health outcomes information. What it does illustrate is the still developmental stage of health outcomes activity in the UK. Providers are the major group of users of outcomes information. The potential impact of health outcomes information on health care commissioning has yet to be realized.

The effects of prenatal adrenal stimulation and synthetic glucocorticoid supplementation on development of the gastro-intestinal tract of the piglet were investigated. Twelve pregnant sows were treated with either ACTH infusion, Isoflupredone injection or Saline between days 105 and 112 of gestation. Neonatal pigs were weighed, bled and sacrificed at 0 or at 6 h. Piglets sacrificed at 6 h were fed bovine colostrum. Transverse sections were prepared from the duodenum, jejunum and ileum for measurement of the villus amplification factor (VAF) and basal membrane circumference. Sows in the ACTH group showed an elevation in cortisol in response to infusion; this decreased after infusion and then rose again at parturition. Piglets from both the ACTH and Saline groups had more villus surface area per unit of body weight (BW) than those born to Isoflupredone-treated animals. The BW of the ACTH piglets was lower (P less than 0.05) than those of piglets in the other groups. When the weight of the stomach and the Small Intestine (SI) was expressed as a function of the body weight, the stomach and SI:BW ratio was larger (p less than 0.05) in pigs born to ACTH-treated sows. The circumference of the ileum was larger at 6 h than at 0 h. Control pigs had a higher concentration of bovine IgG at 4 and 6 h (P less than 0.05). Observations of the light microscopic preparations indicated a less organized epithelium in both ACTH and isoflupredone pigs sacrificed at 0 h. Light and EM preparations of ileum from ACTH pigs sacrificed at 6 h, showed an abundance of dark-stained vacuoles, characteristic of IgG-containing structures. These became less evident in piglets from the Isoflupredone group and even less so in the control groups. The consequences of these phenomena in terms of absorptive capacity are discussed.

Pig blastocysts aged 14, 16 and 18 days were divided into 15 cm segments representing tissue adjacent to the embryonic disc, an intermediate section and the tip region. Whenever total blastocyst length allowed, the intermediate segment was divided into proximal and distal portions for separate culture. All were rinsed with buffer and incubated with dehydroepiandrosterone for 3 h. Rinsing buffer and incubation medium were subsequently assayed for concentrations of oestrone and oestradiol-17 beta. The highest production of oestrogen was found in the embryonic disc region. The intermediate regions had the lowest synthetic ability, while the tip region produced more oestrogens than the intermediate regions but less than the disc region. The production of oestrone was higher (P less than 0.05) in 18-day-old blastocysts than in younger ones while oestradiol-17 beta production was lower (P less than 0.05) on Day 16. The proportional role of the embryonic disc region as oestrogen-producing tissue increased over time. On Day 14, each intermediate region produced over 70% as much oestrogen as the disc region. These proportions declined on Days 16 and 18 to about 50 and 30% respectively. The regional variation in the ability of blastocysts to produce oestrogens may have some influence on the ability of the blastocyst to create an adequate microenvironment within the uterus which permits successful differentiation and placentation.

The effect of estrogens (Es) on piglet viability was determined as measured by birth to suckling intervals. Starting on d 109 postbreeding daily blood samples were obtained from 15 Yorkshire sows, Immediately after birth, blood samples were taken from the umbilical cord (UC) and the vena cava (VC) of piglets, followed by injections via the VC of either estradiol benzoate (EB) or a saline solution. The interval from birth to suckling (BTS), and body weight gain until 96 h was recorded. Total estrone concentration in the sows' serum rose until the day before parturition and declined sharply by d 2 postpartum. Piglets given EB injections had a shorter interval from BTS (P less than .05) and females suckled sooner than males in both the control and treated groups. No significant differences in weight gain were detected between control and treated groups at 2, 24 or 96 h. Higher (P less than .001) levels of estrone and estrone sulphate were found in the UC than in VC samples, but no correlation existed between levels of Es in the UC and VC (P greater than .05). We concluded that Es or other hydroxylated compounds could be acting upon a high control center of the newborn piglet to cause hyperactivity with a consequent reduction in BTS interval.