Association of cocaine- and amphetamine-regulated transcript-immunoreactive elements with thyrotropin-releasing hormone-synthesizing neurons in the hypothalamic paraventricular nucleus and its role in the regulation of the hypothalamic-pituitary-thyroid axis during fasting

Because cocaine- and amphetamine-regulated transcript (CART) coexists with alpha-melanocyte stimulating hormone (alpha-MSH) in the arcuate nucleus neurons and we have recently demonstrated that alpha-MSH innervates TRH-synthesizing neurons in the hypothalamic paraventricular nucleus (PVN), we raised the possibility that CART may also be contained in fibers that innervate hypophysiotropic thyrotropin-releasing hormone (TRH) neurons and modulate TRH gene expression. Triple-labeling fluorescent in situ hybridization and immunofluorescence were performed to reveal the morphological relationships between pro-TRH mRNA-containing neurons and CART- and alpha-MSH-immunoreactive (IR) axons. CART-IR axons densely innervated the majority of pro-TRH mRNA-containing neurons in all parvocellular subdivisions of the PVN and established asymmetric synaptic specializations with pro-TRH neurons. However, whereas all alpha-MSH-IR axons in the PVN contained CART-IR, only a portion of CART-IR axons in contact with pro-TRH neurons were immunoreactive for alpha-MSH. In the medial and periventricular parvocellular subdivisions of the PVN, CART was co-contained in approximately 80% of pro-TRH neuronal perikarya, whereas colocalization with pro-TRH was found in <10% of the anterior parvocellular subdivision neurons. In addition, >80% of TRH/CART neurons in the periventricular and medial parvocellular subdivisions accumulated Fluoro-Gold after systemic administration, suggesting that CART may serve as a marker for hypophysiotropic TRH neurons. CART prevented fasting-induced suppression of pro-TRH in the PVN when administered intracerebroventricularly and increased the content of TRH in hypothalamic cell cultures. These studies establish an anatomical association between CART and pro-TRH-producing neurons in the PVN and demonstrate that CART has a stimulatory effect on hypophysiotropic TRH neurons by increasing pro-TRH gene expression and the biosynthesis of TRH.

Genome scan of human systemic lupus erythematosus by regression modeling: evidence of linkage and epistasis at 4p16-15.2

Systemic lupus erythematosus (SLE) is a complex autoimmune disorder involving at least hormonal, environmental, and genetic factors. Familial aggregation, a 2%-3% sibling recurrence rate, monozygotic twin concordance >20%, association with several candidate genes, as well as the results of five genome scans support a genetic component. We present here the results of a genome scan of 126 pedigrees multiplex for SLE, including 469 sibling pairs (affected and unaffected) and 175 affected relative pairs. Using the revised multipoint Haseman-Elston regression technique for concordant and discordant sibling pairs and a conditional logistic regression technique for affected relative pairs, we identify a novel linkage to chromosome 4p16-15.2 (P=.0003 and LOD=3.84) and present evidence of an epistatic interaction between chromosome 4p16-15.2 and chromosome 5p15 in our European American families. We confirm the evidence of linkage to chromosome 4p16-15.2 in European American families using data from an independent pedigree collection. In addition, our data support the published results of three independent studies for nine purportedly linked regions and agree with the previously published results from a subset of these data for three regions. In summary, results from two new analytical techniques establish and confirm linkage with SLE at 4p16-15.2, indicate epistasis between 4p16-15.2 and 5p15, and confirm other linkage effects with SLE that have been reported elsewhere.

High risk genes predisposing to prostate cancer development-do they exist?

There is evidence for genetic predisposition to prostate cancer. However, prostate cancer genes have been more difficult to find than genes for some of the other common cancers, such as breast and colon cancer. The reasons for this are discussed in this article and it is now becoming clear that prostate cancer is probably due to multiple genes, many of which are moderate or low penetrance. The advances in the Human Genome Project and technology, especially that of robotics, will help to overcome these problems. Prostate Cancer and Prostatic Diseases (2000) 3, 241-247

Chemical and serological characterization of the Bordetella hinzii lipopolysaccharides

Bordetella hinzii has recently been isolated from immunocompromised human hosts. The polysaccharides isolated from its endotoxin (lipopolysaccharide, LPS) were investigated using chemical analyses, NMR, gas-liquid chromatography/mass spectrometry and mass spectrometry by plasma desorption, matrix-assisted laser desorption/ionization and electrospray. The following structure for the O-chain-free LPS was deduced from the experimental results: carbohydrate structure [see text] Mass spectrometry and serology revealed that the O-chains were different from the homopolymer common to Bordetella bronchiseptica and Bordetella parapertussis strains and were composed of a trisaccharide repeating unit. Masses up to 8 kDa were obtained for native LPS molecular species.

What risk factors tell us about the causes of schizophrenia and related psychoses

Genetic, epidemiologic, and molecular studies concur that liability to schizophrenia is transmitted through the inheritance of a number of genes of relatively small effect, some of which are shared with other psychoses. Each of these susceptibility genes causes minor deviations that are relatively innocent in themselves, for example, increased lateral ventricular volume, schizotypal personality, or subtle cognitive difficulties. However, when an individual is unlucky enough to inherit several of these traits, their cumulative effect, often compounded by environmental hazards, propels that person over a threshold for the expression of frank psychosis. Early environmental risk factors for schizophrenia include urban and winter birth, fetal malnutrition and hypoxia, and possibly prenatal viral infections; these early hazards have only a modest risk-increasing effect, and operate in the context of genetic risk. Preschizophrenic children are more likely to have minor psychomotor and cognitive problems; low IQ has a linear relationship with risk for schizophrenia. However, schizophrenia is not simply a neurodevelopmental disorder, because risk factors have been identified that have their effects proximal to the onset of psychosis: drug abuse, immigrant status, and social adversity and isolation. Both genetic and environmental risk factors appear to operate across diagnostic categories and therefore support a dimensional model of psychosis.

Causes of the acute abdomen: add thrombophilia to your list

A47-year-old male was admitted with a 2-week history of periumbilical discomfort. For 48 hours before admission, the patient suffered from associated vomiting and anorexia. Upon admission the abdominal pain had become more severe and began to radiate to both flanks.

His past medical history included a deep vein thrombosis 18 months previously. He was taking Tegretol for epilepsy (seizure free for many years) and regular inhalers for asthma. He had no recent episode of prolonged immobility. He was a non-smoker and did not drink alcohol.

On examination, he was obese (96 kg). He had a low grade pyrexia with a sinus tachycardia (120 beats per minute). He was normotensive. Abdominal examination revealed tenderness over the umbilical and epigastric areas. At this stage, there was no evidence of guarding or rigidity and bowel sounds were present.

Investigations including serum bioprofile, amylase, coagulation screen, chest X-ray, plain film of abdomen and ultrasound of abdomen were all reported as normal. Full blood count revealed a moderate leucocytosis (13.2 × 109/litre).

At this stage he was managed conservatively with intravenous fluids and antibiotics. However, over the next 12 hours, the patient's condition deteriorated and he developed diffuse peritonism with guarding and rebound tenderness. He was prepared for theatre. Laparoscopy demonstrated haemosanguinous fluid and gangrenous loops of small bowel. Laparotomy confirmed the presence of a 24” gangrenous segment of distal jejenum and proximal ileum. Perioperatively, this segment was noted to have good arterial pulsation with obvious clot in the venous arcades. Formal resection with end to end anastomosis was completed. Postoperative recovery was uneventful. After surgery he was anticoagulated with unfractionated heparin.

Histology confirmed mesenteric venous infarction. In view of the past history of deep vein thrombosis, a thrombophilia screen was performed. Our patient was heterozygous positive for the factor V leiden mutation. He was anticoagulated and discharged on warfarin indefinitely (under ongoing review).

Scissors: are they an infection control risk?

Increasing bacterial resistance means that nurses must re-examine infection control procedures. Bacteria were cultured from 59% of scissors swabbed. Some were still contaminated after cleaning. Some nurses do not appear to recognise the risk of infection from using their scissors for a variety of purposes.

A case of haemophagocytic syndrome and Kikuchi-Fujimoto disease occurring concurrently in a 17-year-old female

An unusual case in which a young Asian female presenting with fever, lymphadenopathy and cytopaenia was found to have distinct histological features of both haemophagocytic syndrome (HS) and histiocytic necrotising lymphadenitis (Kikuchi-Fujimoto disease, KFD) is presented. We review the clinical features of each of these rare, but important, diagnoses and propose the hypothesis that they may form part of a disease continuum, rather than representing separate entities.

Serum haptoglobin: an objective indicator of experimentally-induced Salmonella infection in calves

Experimental models of Salmonella -induced gastroenteritis have previously relied on crude subjective clinical markers of infection to assess disease severity. The aim of this study was to investigate the possibility that changes in serum levels of the acute phase protein, haptoglobin, may be used as an objective, quantitative measurement of infection. Eight 3- to 4-week-old animals were challenged with a mixture of three Salmonella serotypes containing 6 x 10(10)bacteria and compared with five animals given a placebo preparation. Animals were monitored and characteristic clinical symptoms of infection; diarrhoeal scores, morbidity scores and rectal temperature, were recorded. Serum samples, from both animal groups, taken prior to challenge and again on days 1, 3, and 5 post-challenge, were analysed for haptoglobin levels using a direct serum binding assay. Prior to challenge, all 13 animals had normal levels of haptoglobin in their serum. By day 3 post-challenge six of eight animals challenged with Salmonella had abnormal serum haptoglobin levels (median level = 212 microg ml(-1)), while haptoglobin levels remained normal in placebo-challenged animals (median level = 0 microg ml(-1)). The change in haptoglobin levels during the 5-day observation period was statistically significant in the Salmonella -challenged animals (P = 0.0003, H = 16.477). Serum haptoglobin levels showed a statistical correlation with clinical measures of disease severity; diarrhoeal scores (P = 0.0015, H =8. 988), morbidity scores (P = 0.0004, H = 15.711) and rectal temperature (P = 0.0001, Z = 4.304). Thus, serum haptoglobin levels closely reflect the clinical symptoms of infection and are therefore a useful marker of infection severity in salmonellosis in calves.

Immunotherapy against antibiotic-resistant bacteria: the Russian experience with an antistaphylococcal hyperimmune plasmaand immunoglobulin

The Russian experience with the preparation and clinical application of an antitoxic antistaphylococcal hyperimmune plasma and immunoglobulin is described. The immunotherapies were developed in the late 1960s and put into widespread use in the Soviet Union for the prophylaxis and treatment of sepsis, pneumonia, and other conditions caused by an epidemic of antibiotic-resistant Staphylococcus aureus.

Phase I and pharmacokinetic study of 10-propargyl-10-deazaaminopterin, a new antifolate

The 10-deazaaminopterins are a new class of rationally designed antifolates demonstrating greater antitumor effects than methotrexate in murine tumor models and human tumor xenografts. Their design was aimed at improving membrane transport and polyglutamylation in tumor cells, resulting in increased intracellular accumulation and enhanced cytotoxicity. Compared with other 4-aminofolate analogues, 10-propargyl-10-deazaaminopterin (PDX) is the most efficient permeant for the RFC-1-mediated internalization and substrate for folylpolyglutamate synthetase. PDX demonstrates greater in vitro and in vivo antitumor efficacy than methotrexate or edatrexate. We undertook a Phase I study with PDX to identify the potential toxicities and define an optimal dose and schedule. Thirty-three patients were enrolled, all of whom had non-small cell lung cancer (NSCLC) and were treated previously with a median of two prior chemotherapy regimens. Initially, PDX was administered weekly for 3 weeks in a 4-week cycle. Mucositis requiring dose reduction and/or delay in the first cycle occurred in four of six patients treated at the initial dose level (30 mg/m2), making this the maximal tolerated dose for PDX given on this schedule. The treatment schedule was then modified to every 2 weeks. Twenty-seven patients were treated twice weekly with a total of 102 four-week cycles (median, 2 cycles/patient). Mucositis was the dose-limiting toxicity, with grade 3 and 4 mucositis occurring in the first two patients treated at the 170 mg/m2 dose level. Other toxicities were mild and reversible. No neutropenia was observed. The recommended Phase II dose is 150 mg/m2 biweekly. At that dose level, the mean area under the curve was 20.6 micromol x h, and the mean terminal half-life was 8 h. Two patients with stage IV NSCLC had major objective responses, and five patients had stable disease for 7 (two patients), 9 (one patient), 10 (one patient), and 13 months (one patient). PDX is a new antifolate with manageable toxicity and evidence of antitumor activity in NSCLC. A Phase II trial in NSCLC and a Phase I trial with paclitaxel are under way. These studies will also quantitate the expression of genes controlling internalization (RFC-1) and polyglutamylation of PDX in tumor cells as correlates of response.

The frequency of germ-line mutations in the breast cancer predisposition genes BRCA1 and BRCA2 in familial prostate cancer. The Cancer Research Campaign/British Prostate Group United Kingdom Familial Prostate Cancer Study Collaborators

Predisposition to prostate cancer has a genetic component, and there are reports of familial clustering of breast and prostate cancer. Two highly penetrant genes that predispose individuals to breast cancer (BRCA1 and BRCA2) are known to confer an increased risk of prostate cancer of about 3-fold and 7-fold, respectively, in breast cancer families. Blood DNA from affected individuals in 38 prostate cancer clusters was analyzed for germ-line mutations in BRCA1 and BRCA2 to assess the contribution of each of these genes to familial prostate cancer. Seventeen DNA samples were each from an affected individual in families with three or more cases of prostate cancer at any age; 20 samples were from one of affected sibling pairs where one was < or = 67 years at diagnosis. No germ-line mutations were found in BRCA1. Two germ-line mutations in BRCA2 were found, and both were seen in individuals whose age at diagnosis was very young (< or = 56 years) and who were members of an affected sibling pair. One is a 4-bp deletion at base 6710 (exon 11) in a man who had prostate cancer at 54 years, and the other is a 2-bp deletion at base 5531 (exon 11) in a man who had prostate cancer at 56 years. In both cases, the wild-type allele was lost in the patient's prostate tumor at the BRCA2 locus. However, intriguingly, in neither case did the affected brother also carry the mutation. Germ-line mutations in BRCA2 may therefore account for about 5% of prostate cancer in familial clusters.

The production and biological assessment of cervine interferon gamma

Cervine interferon gamma (IFN-gamma) was cloned and expressed using an Escherichia coli expression system pET-32. The expressed protein contained a 6 histidine purification tag and an 11 kDa thioredoxin fusion partner 5' to the IFN-gamma molecule. The ability of IFN-gamma to inhibit the killing of Madin-Darby bovine kidney cells by Semliki forest virus was used as a measure of the bioactivity of the recombinant cervine IFN-gamma (rIFN-gamma). It was shown that the presence of the thioredoxin fusion partner 5' to the IFN-gamma molecule did not affect its biological activity. As in the mouse model, it was shown that cervine rIFN-gamma was able to down-regulate the transcription of interleukin 10 mRNA while up-regulating the transcription of interleukin 12 mRNA in lipopolysaccharide-sensitized, peripheral blood mononuclear cells. A prototype ELISA was tested for its ability to detect both recombinant and native IFN-gamma. The ELISA was able to detect rIFN-gamma at concentrations greater than 100 pg/ml. It was also used to detect native IFN-gamma produced by peripheral blood lymphocytes from Mycobacterium bovis infected or vaccinated deer after in vitro restimulation with antigen. The rIFN-gamma and the cervine IFN-gamma specific ELISA provide valuable tools with which to study important zoonotic infections in farmed and wild deer.

Schizophrenia is not disappearing in south-west Scotland

BACKGROUND

Recent work has reported a decline in the incidence of schizophrenia, but it is unclear if these findings reflect a true decrease in its incidence or are an artefact arising from methodological difficulties.

AIMS

To take account of these methodological difficulties and report service-based incidence rates for schizophrenia in Dumfries and Galloway in south-west Scotland for 1979-98.

METHOD

Using both clinical diagnoses and diagnoses generated from the Operational Checklist for Psychotic Disorders (OPCRIT) computer algorithm for ICD-10 and DSM-IV schizophrenia, we measured change in the incidence rates over time. We used indirect standardisation techniques and Poisson models to measure the rate ratio linear trend.

RESULTS

There was a monotonic and statistically significant decline in clinically diagnosed schizophrenia. The summary rate ratio linear trend was 0.77. However, using OPCRIT-generated ICD-10 and DSM-IV diagnoses, there was no significant difference over time.

CONCLUSIONS

OPCRIT-generated consistent diagnoses revealed no significant fall in the incidence of schizophrenia. Changes in diagnostic practice have caused the declining rates of clinically diagnosed schizophrenia in Dumfries and Galloway.

Nutritional status and its relationship to quality of life in a sample of chronic hemodialysis patients

OBJECTIVE

To assess the relationship between nutritional status and quality of life in a sample of chronic hemodialysis patients.

DESIGN

Cross-sectional study.

SETTING

Haemodialysis Units of St Vincent's and St George Hospitals, Sydney, Australia.

PATIENTS

Sixty-four patients participated in the nutritional assessment, of which 53 completed the quality of life questionnaire.

INTERVENTION

Nutritional status was assessed using subjective global assessment in addition to a number of anthropometric and biochemical parameters. Quality of life was assessed by means of a patient questionnaire and assessment of physical functioning.

MAIN OUTCOME MEASURES

Nutrition status, 6 quality of life subscales related to general well-being, health and functioning, social and economic, psychological/spiritual well-being, and family life, employment status, income, participation in recreational/sports activities, the number of hospital admissions, days of hospitalization, and lengths of hospital stay.

RESULTS

Sixty-four percent of patients were well nourished, 23% were moderately malnourished, and 13% were severely malnourished. Malnutrition was associated with poorer subjective quality after controlling for the affects of sociodemographic and medical variables. Severe malnutrition was also independently associated with poorer physical function, and resulted in significantly more hospital admissions, more days of hospitalization, and longer average lengths of hospital stay.

CONCLUSION

Malnutrition is common in chronic hemodialysis patients and is associated with poorer quality of life when the degree of malnutrition becomes severe. Prospective studies are required to determine whether improving the nutritional status of these patients will result in meaningful improvements in quality of life and other medical outcomes.