[Unusual alcoholic weaning, complicated: do you check the blood phosphate?]

A 65 year old alcoholic man was hospitalized because he was tired, hypotonic, with postural tremor. The neurologic symptoms increased during the first two days despite an adequate therapy for alcoholic weaning with hydratation, benzodiazepines and vitamins. A severe hypophosphatemia is diagnosed, associated with hypovitaminosis D, mild hypomagnesemia, mild hypokaliemia and a refeeding syndrome. 24 hours after the normalisation of his phosphatemia, the neurologic symptoms are adjusted.

Estimating the cost-effectiveness of vaccination against herpes zoster in England and Wales

A live-attenuated vaccine against herpes zoster (HZ) has been approved for use, on the basis of a large-scale clinical trial that suggests that the vaccine is safe and efficacious. This study uses a Markov cohort model to estimate whether routine vaccination of the elderly (60+) would be cost-effective, when compared with other uses of health care resources. Vaccine efficacy parameters are estimated by fitting a model to clinical trial data. Estimates of QALY losses due to acute HZ and post-herpetic neuralgia were derived by fitting models to data on the duration of pain by severity and the QoL detriment associated with different severity categories, as reported in a number of different studies. Other parameters (such as cost and incidence estimates) were based on the literature, or UK data sources. The results suggest that vaccination of 65 year olds is likely to be cost-effective (base-case ICER=pound20,400 per QALY gained). If the vaccine does offer additional protection against either the severity of disease or the likelihood of developing PHN (as suggested by the clinical trial), then vaccination of all elderly age groups is highly likely to be deemed cost-effective. Vaccination at either 65 or 70 years (depending on assumptions of the vaccine action) is most cost-effective. Including a booster dose at a later age is unlikely to be cost-effective.

The comparative sero-epidemiology of varicella zoster virus in 11 countries in the European region

The European sero-epidemiology network (ESEN2) aims to standardise serological surveillance of varicella zoster virus (VZV) in 11 participant countries. In each country, serum banks were collected between 1996 and 2003 and tested for VZV antibodies. Assay results were standardised so that international comparisons could be made. Age-specific forces of infection were calculated for three age groups (<5, 5-9 and >or=10 years of age) and used to estimate the base reproduction number (R(0)) and the herd immunity threshold (H). Most VZV infection occurred in childhood, but there was a wide variation in transmissibility, with R(0) ranging from 16.9 in the Netherlands to 3.3 in Italy. Herd immunity thresholds varied from 70% in Italy to 94% in the Netherlands. There are substantial differences in VZV sero-epidemiology within the European region, which will need to be taken into account in designing national policies regarding VZV vaccination.

European Sero-Epidemiology Network: standardisation of the assay results for pertussis

A standardisation process was developed in order to compare and harmonize serological results of pertussis toxin (PT) antibody measurements performed by laboratories using different technical procedures for detection. This involved the development of a common panel, of sera by a designed reference centre, the distribution of the panel to each participating laboratory for testing with their routine methods, the comparison of the obtained results to those of the reference centre, and the calculation of standardisation equations by regressing the quantitative results against those of the reference centre. As a cut-off indicative of protection against pertussis has not yet been defined, a particular emphasis was laid upon achieving standardisation of high titre results that would allow epidemiological evaluations based on the estimation of the incidence of recent infections rather than on the traditional approach of determining the population immunity profile. A generally good agreement was achieved between the participating laboratories, all using ELISA procedures very similar in many crucial aspects, and standardisation equations were produced useful to enable inter-country comparison during the next stages of the European Sero-Epidemiology Network (ESEN) project concerning the serological surveillance of immunity to pertussis in Europe.

Family physicians' initiative to increase compliance with screening mammography--an innovative community project

BACKGROUND

Breast cancer is the most common malignancy among women in Israel and throughout the world. Israeli women aged 50-75 years are advised to undergo a mammographic screening examination every 2 years. However, the lack of a structured referral system is reflected in the low utilization rate of mammography.

OBJECTIVES

To describe an innovative program in which family physicians in an urban clinic developed a model framework for referrals, coordinated with radiologists and surgeons, aimed at increasing compliance among women referred for mammography.

METHODS

A community-based study was conducted, outside of the regular reception hours, in a neighborhood practice with a population of 527 women aged 50-75. A referral system under the supervision of family physicians was designed, and the women received appointments for mammography at specified days and hours. The results of the examination were sent to the physician who used dedicated time to continue the diagnostic and/or therapeutic process, as appropriate. At the physician's instructions a research assistant contacted the women who did not keep their appointments, and scheduled a second appointment.

RESULTS

In 1993, the year prior to the study, when women referred themselves for mammography, the utilization rate was 9%. During the study year the utilization rate was 77%. Women born in Europe or America had higher compliance rates than women born in Asia or Africa (81% vs. 72%, respectively). Married women were more compliant than unmarried women (81% vs. 70%, respectively). No correlation was found between compliance and age, family history of cancer in general, or breast cancer in particular. Six new cases of breast cancer were detected.

CONCLUSIONS

The initiative of family physicians increased the utilization of mammography among women under their care. Family physicians allocated time outside of their regular reception hours for the program. A relatively large number of new malignancies were found, but this impression should be confirmed or negated by a large-scale study using the same methods.

Ten years of serological surveillance in England and Wales: methods, results, implications and action

BACKGROUND

The first age-stratified serological survey of antibody to measles, mumps and rubella in the UK was conducted in 1986/87 prior to the introduction of MMR vaccine into the immunization programme. Serum collection and testing have continued annually, allowing trends over time to be monitored. These sera have also been available for ad hoc surveys of other infections.

METHODS

Residual sera are collected in participating laboratories and sent to a central store where they are irrevocably unlinked from identifying data. A unique identity number is assigned to each serum and details of age and sex are collated on a database. The sera are accessed for testing as required.

RESULTS

The results of recurring and other surveys performed over the last ten years are presented. These demonstrate that opportunistic serum samples are an ideal resource for serological surveillance programmes.

CONCLUSIONS

The serological surveillance programme has provided past exposure profiles for many infections. These data have resulted in a number of national policy changes and have been instrumental in shaping the UK vaccination programme.

Factors associated with occupational exposure and compliance with universal precautions in an urban school district

Factors associated with occupational exposure and universal precautions (UP) compliance were assessed among employees in one urban school district. Half of the employees surveyed reported responding to bleeding injuries and cleaning blood or other body fluids (e.g., vomit, urine) during the previous school year. Also, 1 in 4 custodians and 1 in 10 teachers/teacher's aides had direct contact with blood or body fluids without protection. In multivariate logistic regression analyses, direct contact was most likely among secondary school employees in unpredictable situations who did not have protective equipment or comply with UP. UP compliance was greater among those who had protective equipment available and felt self-confident. Self-confidence was associated with having received training or protective equipment. Routine communications between administrators and employees, staff training, provision of protective equipment, and exposure incident monitoring are essential to effective implementation of UP policies in schools and work settings where occupational exposure could occur.

An estimate of the proportion of diarrhoeal disease episodes seen by general practitioners attributable to rotavirus in children under 5 y of age in England and Wales

Mean weekly incidence rates for a 4-week period of new episodes of infectious intestinal disease (IID) and laboratory reports of faecal isolations in children under 5 y of age presenting in general practice were used to estimate the incidence of IID due to rotavirus infection in England and Wales. Between January 1992 and December 1996, a total of 92452 new episodes of IID were seen at sentinel general practices and reported to the Royal College of General Practitioners (RCGP) Research Unit in Birmingham, UK. Of these 32% (29592) were in children under 5 y of age. During the same period the Communicable Disease Surveillance Centre (CDSC) in London, UK received 159532 reports of faecal identifications in children under 5 y of age; 69219 (43%) of these were due to rotavirus. By modelling RCGP data and laboratory reports, the proportion of episodes attributable to rotavirus infection was estimated to be 29% (95% CI: 24% to 34%). By extrapolation of RCGP data it was estimated that rotavirus accounted for 762000 of new episodes of IID nationally in children under 5 y of age between January 1992 and December 1996. Implementation of a rotavirus vaccination programme could substantially reduce the incidence of childhood diarrhoea.

Localization of nitric oxide-synthesizing neurons sending projections to the dorsal raphe nucleus of the rat

The origin of the nerve fibers immunoreactive for neuronal nitric oxide synthase (nNOS) in the rat dorsal raphe nucleus (DRN) was determined by combining the use of cholera toxin subunit b (CTb) as a retrograde tracer and nNOS immunohistochemistry with a monoclonal anti-nNOS antibody. Double labeled CTb-nNOS cell bodies were distributed from the rostral diencephalon to the caudal medulla oblongata, in about 20 areas of the brain. Several of the areas displaying double labeled cells are known for their involvement in the control of the sleep-wake cycle and/or transmission of nociception.

Comparative distribution of nitric oxide synthase- and serotonin-containing neurons in the raphe nuclei of four mammalian species

Monoclonal antibodies were generated against serotonin (5-HT) and the C-terminal portion of the neuronal form of nitric oxide synthase (nNOS), the enzyme producing nitric oxide in neurons. These antibodies were used to compare the distribution of 5-HT- and nNOS-containing neurons in the raphe nuclei of four animal species (rat, mouse, guinea pig, and cat). It was found that the rat was the only species in which the raphe nuclei contain a substantial number of nNOS-immunoreactive (IR) cell bodies. In this species and as observed by other authors, all mesencephalic raphe nuclei contained nNOS-IR cells, the largest group being located in the nucleus raphe dorsalis. The coexistence of nNOS and 5-HT immunoreactivities in these nuclei was visualized by double labeling. In the medulla, the nuclei raphe magnus and obscurus displayed a rather low number of nNOS-IR neurons. In the other species, nNOS-IR cell bodies were found in very low numbers, whatever raphe nucleus was considered. The rostral pole of the nucleus raphe dorsalis and the nuclei raphe magnus and obscurus contained a few nNOS-IR neurons which did not show any coincidence with the 5-HT neurons. In addition, nNOS-IR axons were rare. It is concluded that in the mouse, guinea pig, and cat the involvement of nitric oxide in functions subserved by 5-HT within the raphe nuclei might be minimal.

Control of hepatitis B in the United Kingdom

Control of hepatitis B in the UK is based upon selective vaccination of persons in high-risk groups. To assess the likely cost-effectiveness of changes to this policy, information on the current burden of HBV infection in the UK is required. Laboratory reports of acute hepatitis B suggest that the vast majority of new hepatitis B infections acquired in the UK occur in adults, even after adjustment for unapparent infection. In childhood, perinatal transmission remains the most significant known risk factor. Universal antenatal screening has the potential to prevent perinatal infections in UK births and a substantial proportion of those UK acquired infections which lead to carriage. In addition, to antenatal screening, universal infant vaccination (at 2, 3 and 4 months) can, in the short term, only prevent the small number of infections acquired in childhood. Economic analysis using current surveillance data is required to assess the possible cost-benefit of universal vaccination. Regardless of this, there is an urgent need to improve selective vaccination and to ensure that a high proportion of antenatal carriers is identified.

The epidemiology of rubella in England and Wales before and after the 1994 measles and rubella vaccination campaign: fourth joint report from the PHLS and the National Congenital Rubella Surveillance Programme

The national immunisation campaign carried out in the United Kingdom in November 1994 was designed to give children aged 5 to 16 years of age a single dose of a combined measles and rubella vaccine. Its main objective was to prevent an epidemic of measles predicted in school age children. The rubella component of the vaccine was included in order to reduce the high level of susceptibility to rubella in young adult males and thus reduce the risk of transmission from this group to pregnant women. Susceptibility to rubella in children aged 5 to 16 years has fallen from 15.7% to 3.4% since the measles and rubella campaign. Despite this the incidence of laboratory confirmed rubella rose substantially in 1996, largely on account of cases among males aged 17 to 24 years, who were not vaccinated in the 1994 campaign and about 16% of whom are susceptible. The impact of the resurgence on the incidence of infection in pregnancy has been relatively limited, due to the low level of susceptibility in the antenatal population (2% in nulliparous and 1.2% in parous women for 1994/5). No cases of congenital rubella arising from administration of measles and rubella vaccine during the campaign have been identified. The numbers of babies born with congenital rubella and terminations of pregnancy for rubella arising from the 1996 resurgence are expected to be similar to those that followed the 1993 resurgence. The reduction in susceptibility in future cohorts of young men who received measles and rubella vaccine in the 1994 campaign should prevent future resurgences after the year 2000. If a second dose of measles, mumps, and rubella (MMR) vaccine had not been introduced, susceptibility levels in the school age population would have risen to about 12% in the future. The effect of the second dose of MMR vaccine introduced for children aged 4 to 5 years in October 1996 will be assessed through serological surveillance.

The epidemiology of measles in England and Wales since the 1994 vaccination campaign

The incidence of measles in England and Wales has fallen since the national vaccination campaign in November 1994, in which 92% of children aged 5 to 16 years were vaccinated. A total of 148 confirmed cases with onsets in the 18 months from January 1995 to June 1996 have been ascertained. Notified cases did not provide a reliable measure of incidence: 11,343 suspected cases were notified in the same period, 6426 (57%) of whom were tested for salivary antibody. Only 90 (1.4%) of cases tested were confirmed. Many confirmed cases occurred in small clusters; 12 imported cases were identified. The pattern of small, local clusters is what would be expected from the introduction of imported cases into a population with herd immunity. Serological surveillance showed that the campaign produced a significant fall in the proportion of 5 to 16 year old children with low levels of measles antibody: the proportion with levels < 50 mIU/ml fell from 8.4% to 2.1%; the proportion with levels < 100 mIU/ml fell from 15.7% to 6.6%. About 15% of 2 to 4 year old children had antibody levels < 100 mIU/ml before and after the campaign. The addition of a routine second dose of measles vaccine (as measles, mumps, and rubella vaccine) to the vaccination schedule will provide another opportunity to immunise these children before they start school. The two dose vaccination programme should maintain the herd immunity of the population and the elimination of endemic measles transmission.

Mumps surveillance in England and Wales supports introduction of two dose vaccination schedule

Sentinel surveillance in general practice and laboratory reports to the PHLS Communicable Disease Surveillance Centre show that the incidence of mumps has fallen to very low levels since vaccination against measles, mumps, and rubella was introduced in 1988. Hospital admissions for mumps show a 92% decline compared with the prevaccination era, to a rate of 0.2 per 100,000 population per year. Serological surveillance has shown an increase in the proportion of school age children who have no detectable antibody to mumps, which is consistent with the reduction in mumps virus transmission. The proportion of children aged 11 to 15 years with no detectable antibody is expected to peak at 19% in 1997. Mathematical models suggest that this increase in susceptibility is unlikely to allow a large resurgence of mumps in the short term but that school outbreaks may become more common. Outbreaks in universities and military establishments are possible in the medium term. Analysis of efficacy data for mumps vaccine indicates that mumps is unlikely to be eliminated with a single dose of vaccine at current coverage rates. A second dose of vaccine, which is now being offered to preschool children, will reduce morbidity and should eventually eliminate mumps if coverage is high enough.

Widespread increase in brain protein synthesis following acute immobilization stress in adult rat brain

The autoradiographic method with [L-35S]methionine was used to determine the effects of a 2 h acute immobilization stress followed by a 4 h recovery on local rates of protein synthesis in the adult rat brain. Methionine incorporation into proteins was significantly increased (from 17 to 86%) in 37 out of the 39 analyzed brain structures. These results show that the stress-induced activation of the overall rate of brain protein synthesis may persist for at least 4 h after cessation of the stimulus even though the stress-related physiological variables have returned to basal levels. They suggest that increased protein synthesis may play a key role in the molecular events which lead to the neuronal plastic changes following an acute stress.

Cerebral protein synthesis alterations in response to acute and chronic immobilization stress in the rat

The quantitative autoradiographic method with L-(35S)methionine was used to determine the effects of 1-acute (4h) and 2-chronic (14 days) immobilization stress followed by one week of recovery. Acute stress induced a significant decrease in methionine incorporation into proteins in 17 of the 35 brain structures examined (mean effect: -22%), and a significant increase in the prepositus hypoglossal nucleus (+23%). Chronic stress induced a significant decrease in methionine incorporation into proteins in 8 of the 35 structures analyzed. Only 4 structures were similarly affected in both these conditions. Our results indicate that stress-induced specific molecular changes in brain are also associated with changes in more general molecular components of cellular metabolism.

Triiodothyronine does not affect the average incorporation of L-[35S]methionine in rat brain structures

The autoradiographic method with L-[35S]methionine was used to examine the effect of acute administration of L-triiodothyronine on local rates of brain protein synthesis in free-moving adult rats. Triiodothyronine was given intraperitoneally at doses of 12.5 or 25 micrograms kg-1. It did not modify the rate of plasma methionine incorporation in the 40 brain regions examined, despite a 4- to 8-fold increase of plasma free triiodothyronine levels. Biochemical analysis confirmed that triiodothyronine (25 micrograms kg-1) had no apparent effect on the overall rate of protein synthesis in the brain as a whole. These results suggest that changes in the circulating levels of thyroid hormones do not exert a general and direct metabolic effect in brain of intact adult rats.

Tower of London procedure: a standard method and developmental data

The Tower of London procedure (TOL) is being utilized increasingly in clinical and experimental contexts, although there is considerable variation in how it is administered and scored. The procedure detailed here was developed using Shallice's original problems and, along with the Porteus Maze Test (PMT), was administered to 205 elementary school students and 74 young adults. TOL scores increased with age in a linear fashion, and the performance of the sixth, seventh, and eighth grade subjects were not statistically different from the young adults. The TOL was moderately correlated with the PMT suggesting that these procedures share a planning component. These data provide initial developmental standards, and the materials, administration, and scoring procedures documented here provide a standard method for utilization of this instrument.

The epidemiology of measles in England and Wales: rationale for the 1994 national vaccination campaign

An epidemic of between 100,000 and 200,000 cases of measles during 1995 has been predicted in England and Wales. This prediction was based on epidemiological evidence from several sources. Notifications of measles to the Office of Population Censuses and Surveys have risen in 1994, with a high proportion of cases in children aged over 10 years. An increase in the incidence of measles was seen in data from other sources, including laboratory reports of confirmed infections and consultations with general practitioners for new episodes of measles. Antibody tests were performed on saliva and serum from notified cases in several districts. Over three quarters of the notified cases in 1994 that were confirmed occurred in children of school age. The proportion of children aged 7 to 14 years who were susceptible to measles, obtained from studies of the age specific prevalence of antibody, rose from 6.0% (146/2453) in 1986 and 1987 to 9.2% (144/1565) in 1991. Mathematical modelling has predicted that the level of susceptibility anticipated in the school age population in 1995 would have been sufficient to allow a resurgence of measles. Over half of the cases in the resulting epidemic would have occurred in people aged at least 10 years and, because mortality is higher in this older age group, between 30 and 60 deaths would have occurred. A mass campaign to immunise all children of school age is expected to cause an immediate reduction in disease transmission and prevent a substantial toll of morbidity and mortality.

n-3 fatty acid deficiency increases brain protein synthesis in the free-moving adult rat

The autoradiographic method with L-[35S]methionine was used to determine the effects of an n-3 fatty acid deficiency on brain protein synthesis. Brain protein synthesis was significantly increased (from 50 to 150%) in 45 of the 52 brain structures studied in n-3 fatty acid-deficient rats as compared with control animals. Biochemical analysis confirmed the increase in overall rate of protein synthesis in brain as a whole.

Effects of an acute immobilization stress upon proopiomelanocortin (POMC) mRNA levels in the mediobasal hypothalamus: a quantitative in situ hybridization study

The aim of this study was to examine by quantitative in situ hybridization the effects of an acute stress on the expression of the POMC gene in the mediobasal hypothalamus (MBH) of the rat. In control animals, the highest levels of POMC mRNA were observed in the posterior periventricular region of the MBH. Lower levels were found in the anterior and posterior arcuate nucleus. At the end of a one hour immobilization, a small decrease (-8%) was observed in the periventricular region only. Four hours after the end of immobilization, increases in POMC mRNA levels were detected in the anterior part (7%), in the posterior part (25%) and in the periventricular region (13%) of the MBH. These results suggest that MBH POMC-derived peptides might be an important component in the central response to stress.

Adrenalectomy-induced increase of brain protein synthesis is antagonized by corticosterone replacements in free-moving rats

The autoradiographic method with L-[35S]-methionine was used to determine whether changes in glucocorticoid circulating levels were associated with changes in local rates of protein synthesis in rat brain. Chronic bilateral adrenalectomy induced an increase of methionine incorporation rates into proteins in 60 of the 62 brain regions examined (mean effect, +50%). This effect was confirmed biochemically and quantified by correcting for the relative contribution of methionine derived from protein degradation to the precursor pool for protein synthesis in the whole brain. Acute or chronic administration of corticosterone, at doses that normalize basal levels of adrenocorticotrophic hormone, reversed or prevented the adrenalectomy-induced increase of protein synthesis in most regions. However, in nearly all the regions studied (59 of 62), acute corticosterone administration to sham-operated rats did not change the apparent rate of protein synthesis. These results demonstrate that glucocorticoids exert a generalized inhibitory action on brain protein synthesis, because the stimulatory and persistent effect of adrenalectomy on protein synthesis was antagonized by corticosterone replacements at physiological doses. Thus, the regulation of overall brain protein synthesis by glucocorticoids emphasizes the role of neuroendocrine events on long-term neurochemical processes.

Studies of neuroregulators in the brain stem of SIDS

Some dysmaturity of neuroregulator neuronal systems may be responsible for brain stem disorders. These disorders may partly explain the mechanism of death in SIDS. The available data using microbiochemical assays, immunocytochemical techniques and autoradiographic methods seem to show anomalies of some monoaminergic and of some peptidergic systems, especially in the medulla oblongata. All these data need to be confirmed by further studies. It should be understood that one positive effect of such neuroanatomical study on SIDS is to gain 'normative' data on the human brain during development.

Vasopressin mRNA in the cerebellum and circumventricular organs: a quantitative in situ hybridization study

To answer the question as to whether vasopressin is synthesized in brain structures other than the supraoptic and paraventricular nuclei of the hypothalamus, vasopressin mRNA was detected by in situ hybridization in the pituitary, cerebellum, dentate gyrus, habenula and circumventricular organs. The highest levels (0.3-0.2 pmol/g), measured by quantitative autoradiography, were observed in the pituitary intermediate lobe and the granular layers of the cerebellum and dentate gyrus. Lower levels (0.15-0.08 pmol/g) were found in the medial habenula, adenohypophysis, area postrema, pineal, subfornical and subcommissural organs.

Comparison of the effects of chronic water deprivation and hypertonic saline ingestion on cerebral protein synthesis in rats

The effects of 3 days water deprivation and 3 days with 2% (w/v) NaCl in drinking water on local rates of methionine incorporation into brain proteins were compared by means of a quantitative autoradiographic method with L-[35S]methionine. The two conditions of chronic dehydration resulted in large increases in the rate of methionine incorporation in the supraoptic (SON), magnocellular paraventricular (mPVN) and arcuate nuclei of the hypothalamus, and in the subfornical organ (SFO). Significant increases of lower amplitude occurred as a result of both treatments in the anteroventral third ventricle area, parvocellular paraventricular nucleus and locus coeruleus. Water deprivation caused larger increases of protein synthesis than hypertonic saline ingestion in the SON, mPVN and SFO. These results indicate that following chronic dehydration, increases in protein synthesis occur mainly in forebrain areas involved in the regulation of water balance, whereas no major changes in protein synthesis occur in brainstem areas involved in the control of blood volume and pressure.

Progressive increases of protein synthesis in the circumventricular organs during chronic dehydration in rats

The quantitative autoradiographic method with L-(35S)methionine was applied to investigate the effect of chronic dehydration on rates of protein synthesis in circumventricular organs (CVOs). Water deprivation for 1, 2 and 3 days causes progressive increases of protein synthesis in the subfornical organ (SFO), the area postrema, the organum vasculosum laminae terminalis and the neurohypophysis. Chronic salt ingestion with 2% NaCl in drinking water for 3 days resulted in increases of protein synthesis in the CVOs similar to those found after 3 days water deprivation, with only one exception, the SFO, in which the rise in protein synthesis was of lower amplitude after 3 days salt ingestion as compared to 3 days water deprivation. These results suggest that several circulating factors related to intracellular dehydration and the high plasma levels of the neurohormones vasopressin and oxytocin are probably important determinants of the rise of protein synthesis in circumventricular organs. Alternatively, the elevated level of blood-borne angiotensin II may well explain the higher metabolic response of the SFO following water deprivation compared to salt ingestion.

Inhibition of methionine incorporation into brain proteins after the systemic administration of p-chlorophenylalanine and L-5-hydroxytryptophan

The effects of p-chlorophenylalanine (p-CPA) and L-5-hydroxytryptophan (L-5-HTP) on local rates of plasma methionine incorporation into brain proteins were investigated by a quantitative autoradiographic method. The sequential i.v. administration of p-CPA (280 mg/kg, 42 h before the measurement) and L-5-HTP (60 mg/kg, 40 min before the measurement) resulted in an average 82% decrease of plasma methionine incorporation. The two treatments given separately also reduced the rates of plasma methionine incorporation in all the brain areas examined by 33 and 50%, respectively for p-CPA and L-5-HTP. These results indicate that: (1) p-CPA and L-5-HTP, two drugs which affect brain serotonin production in opposite ways, both produce large and general decreases of brain protein synthesis; (2) the administration of L-5-HTP does not restore the p-CPA-induced inhibition of brain protein synthesis but induces further decreases of protein synthesis. These results suggest that the reduction of brain protein synthesis in p-CPA-treated rats is mainly related to high circulating levels of p-CPA and phenylalanine; and that brain serotonin is not the only factor involved in the widespread metabolic changes observed. Such profound alterations of brain metabolism should be considered when interpreting the behavioral and neurochemical effects of p-CPA and L-5-HTP.

Induction of tall fescue toxicosis in heat-stressed cattle and its alleviation with thiamin

Livestock grazing endophyte (Acremonium coenophialum)-infected tall fescue (Festuca arundinacea Schreb. cv. Kentucky 31) at high ambient temperatures may suffer from fescue toxicosis. Adult Angus cows (Bos taurus) were fed 0 to 1 kg/d of 70% infected tall fescue seed containing about 4.4 g of loline alkaloids in factorial combination with thiamin at 0 or 1 g/d. Cows assigned to the zero level of tall fescue seed received a supplement of equivalent energy and protein. Ingestive behavior was measured at 1330 to 1430 EDT during two 4-d periods in two consecutive weeks in August on alfalfa (Medicago sativa L.) pastures using a tethered grazing system. Alfalfa intake per measured grazing session of cows given tall fescue seed declined linearly (P less than .01) as air temperatures during grazing increased above 25 degrees C, largely because of shorter grazing meals. Thiamin increased alfalfa intake per measured grazing session by extending grazing time. Alkaloids in ingested endophyte-infected tall fescue induce thiamin deficiencies in cattle that result in symptoms of tall fescue toxicosis.

Decreased protein synthesis in hypothalamic nuclei following L-5-hydroxytryptophan in intact and p-chlorophenylalanine-pretreated rats

The rate of protein synthesis was estimated in individual hypothalamic nuclei by a quantitative autoradiographic technique with L-[35S]methionine. The i.v. administration of 60 mg/kg L-5-hydroxytryptophan (40 min before) resulted in a 45-55% decrease of overall protein synthesis rate in all the hypothalamic nuclei examined. In rats pretreated (42 h before) with a single i.v. injection of 280 mg/kg p-chlorophenylalanine, a drug which is known to deplete brain serotonin concentration, the administration of 60 mg/kg L-5-hydroxytryptophan resulted in a 50-75% decrease of protein synthesis rates in the hypothalamic nuclei. These results suggest that the systemic administration of large doses of L-5-hydroxytryptophan may inhibit protein synthesis in hypothalamic nuclei directly or indirectly after the conversion of this compound to serotonin.

Bioavailability of magnesium in beef cattle fed magnesium oxide or magnesium hydroxide

Two experiments were conducted to compare Mg bioavailability from Mg oxide (MgO) vs Mg hydroxide (Mg(OH)2) fed in either a completely mixed diet or a mineral supplement. In Exp. 1, these Mg sources were incorporated into completely mixed diets and offered to 15 steers (282 kg) allotted to three treatments: control diet containing .19% Mg, control plus .2% added Mg as MgO, or control plus .2% added Mg as Mg(OH)2. Each calf was fed 5 kg/d of the respective diet during 10-d adjustment and 7-d collection periods. Blood samples were collected on d 1, 3 and 7. Mg supplementation increased (P less than .01) fecal and urinary Mg excretions, whereas apparent Mg absorption (%) and retention were similar (P greater than .10) for all treatments. Plasma Mg concentrations were similar (P less than .10) for calves supplemented with MgO and Mg(OH)2 but were higher (P less than .05) for Mg supplemented than for control calves on d 7. In Exp. 2, these Mg sources were incorporated into mineral supplements and offered free choice to 30 spring-calving beef cows gazing tetany-inducing pastures from March 6 to May 1. Each of three groups of 10 cows was assigned to a 5.7-ha tall fescue pasture and offered either a control supplement or a supplement containing 40% MgO or Mg(OH)2. Blood samplers were collected on d 0, 7, 14, 28, 42 and 56. Plasma Mg concentrations were not different (P greater than .10) for cows offered MgO and Mg(OH)2 but were higher (P less than .01) for Mg-supplemented than for control cows on d 28, 42 and 56.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of the endophyte (Acremonium coenophialum) and associated toxin(s) of tall fescue on serum titer response to immunization and spleen cell flow cytometry analysis and response to mitogens

Experiments were conducted with rats and mice to evaluate the effect of the consumption of endophyte (Acremonium coenophialum) and associated toxin(s) infected tall fescue on humoral and cellular aspects of immune function. Treatment diets were: (1) rodent chow (RC) or (2) rodent chow mixed 1:1 (w/w) with endophyte infected (E+) or (3) non-infected (E-) tall fescue seed. Rats fed the E+ diet in experiment 1 (43 days) exhibited a lower (P less than 0.05) serum titer to sheep red blood cell (SRBC) immunization than those fed the E- diet (38.4 vs 131.3). The E+ rats also had lower (P less than 0.01) white cell counts than either RC or E- groups (5225 vs 8959 and 7491/mm3). Spleen cells from mice fed the E+ diet for 37 days exhibited a reduced (P less than 0.05) response to the mitogens Concanavalin A and lipopolysaccharide. Flow cytometric analysis revealed a significant (P less than 0.01) 42% increase in T suppressor cell numbers in spleens of mice fed the E+ vs RC diets.

Performance and plasma amino acids of growing calves fed corn silage supplemented with ground soybeans, fishmeal and rumen-protected lysine

A 100-d growth study was conducted to evaluate performance and plasma amino acid (AA) responses of 96 crossbred beef calves (220 kg) with ad libitum access to corn silage and supplemented with ground soybeans (GSB) with or without added fishmeal (FM) and (or) rumen-protected lysine (Lys). Calves were allotted by breed, sex and weight to four treatments with three replicate pens of eight calves per pen. The treatments were: GSB, GSB + Lys, GSB + FM and GSB + FM + Lys. The isonitrogenous supplements were top-dressed on corn silage once daily at a level of 2.27 kg/hd, with FM providing one-half of the supplemental N in FM-containing supplements. The Lys-containing supplements provided a daily intake of 6.0 g/hd of rumen-protected Lys. Dry matter intake was similar (P less than .10) for all treatments. Overall ADG and feed efficiency of GSB calves averaged .83 kg/d and 7.39 kg feed/kg gain, respectively, and were 14% lower than the mean of calves fed supplements containing FM and(or) Lys. Lysine was not the principal factor limiting growth because the inclusion of Lys alone in the GSB-containing supplements did not improve (P greater than .10) ADG, feed efficiency or plasma AA concentrations. In contrast, FM supplementation increased (P less than .05) ADG, feed efficiency and plasma concentrations of total AA, total essential AA and total nonessential AA. The inclusion of Lys in the GSB + FM-containing supplement resulted in no further improvement (P greater than .10) in performance.(ABSTRACT TRUNCATED AT 250 WORDS)

Possible increase of dopamine-beta-hydroxylase activity in the locus ceruleus of paranoid schizophrenic patients: a preliminary post-mortem study

Five schizophrenic brains and seven control brains were compared for phenylethanolamine-N-methyl-transferase and dopamine-beta-hydroxylase activities. The two groups were comparable in age, sex, and post-mortem delay before autopsy. A radioenzymatic assay showed a statistically significant increase of dopamine-beta-hydroxylase activity in the rostral part of the locus ceruleus in the schizophrenic brains.

Long-lasting insomnia induced by preoptic neuron lesions and its transient reversal by muscimol injection into the posterior hypothalamus in the cat

In order to analyse the role of the anterior hypothalamus in the regulation of the sleep-waking cycle we made bilateral neuronal lesions at different levels of the anterior hypothalamus in cats, by means of microinjections of a cell-specific neurotoxin:ibotenic acid. These lesions resulted in severe insomnia in eight cats. This insomnia was characterized by a large decrease or even disappearance of paradoxical sleep and deep slow wave sleep and, to a lesser extent, by a decrease of light slow wave sleep, for 2-3 weeks. In the other five animals, we observed a large reduction of deep slow wave sleep (0-40% of control level), but a less intensive decrease of time spent in paradoxical sleep (50-75% of control level) and no marked effect on light slow wave sleep. During the first 3-6 postoperative days we also noticed hyperthermia in all cats; thereafter, the animals presented only a slight increase in brain temperature which did not appear to trigger the sleep impairment. Histological analysis of the different lesions revealed that the insomnia could be attributed to neuronal cell body destruction in the mediobasal part of the anterior hypothalamus covering; the medial preoptic area and a narrow portion of the lateral preoptic area as well as a restricted part of the anterior hypothalamic nucleus. In order to investigate the putative role of the posterior hypothalamic structures in the mechanism of insomnia after lesion of the mediobasal preoptic area neurons we injected an agonist of GABA into the ventrolateral part of the posterior hypothalamus to locally depress the neuronal activity. The bilateral intracerebral microinjection of muscimol (0.5-5 micrograms) induced a transient intensive hypersomnia (slow wave sleep and paradoxical sleep). These findings indicate that neuronal cell loss in the mediobasal preoptic area induced a long lasting insomnia. Thus, it may be hypothesized that the integrity of this structure is necessary for sleep appearance. Finally, our data are in keeping with an intrahypothalamic regulation of the sleep-waking cycle.

[Comparative efficacy of antibiotic prophylaxis using cefoxitin in one or in three doses in cesarean section]

To compare the effectiveness of three doses and of a single dose of cefoxitin, a second-generation cephalosporin, in preventing infection after nonelective cesarean section, we carried out a prospective study in 255 women who underwent the procedure between March 1983 and February 1985. The rate of postoperative infection was 7% in the group that received three doses and 8% in the one-dose group. The sensitivity and specificity of perioperative cultures were low. The rate of asymptomatic bacteriuria was high, at 20%, but few symptomatic urinary tract infections were found. Routine antibiotic prophylaxis with a single dose is suggested for all nonelective cesarean sections.

Effects of endophyte-infected fescue on concentrations of prolactin in blood sera and the anterior pituitary and concentrations of dopamine and dopamine metabolites in brains of steers

An experiment was conducted to determine if the decrease in circulating concentrations of prolactin in cattle consuming endophyte (Acremonium coenophialum) -infected tall fescue (Festuca arundinacea) was associated with changes in prolactin concentrations in the anterior pituitary and concentrations of dopamine (DA) and its metabolites 3,4-dihydroxyphenyl-acetic acid (DOPAC) and homovanillic acid (HVA) in the stalk median eminence (SME), preoptic area (POA) and hypothalamus (HP). Six crossbred steers that grazed high-endophyte (greater than 90% infected) fescue and four steers that grazed low-endophyte (less than 1% infected) fescue from April to September were slaughtered. Brains and pituitaries were removed and dissected. Extracts from neural tissue were analyzed for DA, DOPAC and HVA using high performance liquid chromatography/electrochemical detection. Pituitary extracts and sera from blood samples taken 5 d prior to slaughter were subjected to prolactin radioimmunoassay. Consumption of high-endophyte fescue was associated with decreased concentrations of prolactin in serum (P less than .01) and in the anterior pituitary (P = .08), decreased (P less than .05) concentrations of DA in the SME and decreased (P less than .01) concentrations of HVA in the POA and HP, but it did not influence levels of DOPAC. These results suggest that endophyte toxins may reduce prolactin synthesis and release and may alter activity of dopaminergic neurons.