Complete maternal isodisomy of chromosome 8 in an individual with an early-onset ileal carcinoid tumor

Uniparental disomy (UPD) is a condition in which diploid individuals possess a chromosome pair from a single parent. In some instances, UPD causes an abnormal phenotype due to imprinting effects, reduction to homozygosity at recessive disease loci, or trisomy mosaicism. Here we report the first account of an individual with apparently nonmosaic complete maternal isodisomy of chromosome 8. This individual was identified during routine genotyping in a genomewide search for type 2 diabetes susceptibility genes, although he does not have diabetes. He is of normal appearance, stature, and intelligence, but there is an unusual history of early onset ileal carcinoid. The discovery of other maternal UPD 8 cases will be necessary to define whether this condition causes a distinct phenotype.

Hippocampal and striatal [(3)H]5-HT reuptake under acute stressors in two rat strains differing for their emotivity

Spontaneously hypertensive rats and Lewis rats differ in their anxiety levels and in their serotonergic and corticotropic responses to stress. Since the 5-HT transporter plays a key role in 5-HT neurotransmission, we have analyzed whether hippocampal and/or striatal [(3)H]5-HT reuptake kinetics are altered by stress in a strain-dependent manner. It was found that forced swimming, treadmill running, or restraint for 30 min affected neither hippocampal nor striatal [(3)H]5-HT reuptake K(m) and V(max) values in the two rat strains. This study, which is the first to examine the impact of acute stress on [(3)H]5-HT reuptake with respect to the nature of the stressor, the brain region analyzed, and the rat strain, could reinforce the hypothesis that extracellular 5-HT levels during stress are representative of 5-HT release.

Greenland Ice Sheet: High-Elevation Balance and Peripheral Thinning

Aircraft laser-altimeter surveys over northern Greenland in 1994 and 1999 have been coupled with previously reported data from southern Greenland to analyze the recent mass-balance of the Greenland Ice Sheet. Above 2000 meters elevation, the ice sheet is in balance on average but has some regions of local thickening or thinning. Thinning predominates at lower elevations, with rates exceeding 1 meter per year close to the coast. Interpolation of our results between flight lines indicates a net loss of about 51 cubic kilometers of ice per year from the entire ice sheet, sufficient to raise sea level by 0.13 millimeter per year-approximately 7% of the observed rise.

Chicken beta-globin 5'HS4 insulators function to reduce variability in transgenic founder mice

Transgenic mice and rats play a vital role in the study of human diseases and the advancement of drug development within the pharmaceutical industry. In this report we describe a method which improves the yield of phenotypically desirable transgenic founder mice resulting from each microinjection session and consequently reduces animal requirements for transgenic production. We have shown that by flanking a tyrosinase minigene with tandem copies of the chicken beta-globin 5'HS4 insulator there is a significant reduction in variability between transgenic lines, with resulting mice exhibiting similar levels of coat pigmentation. Furthermore, the presence of insulators leads to visually identical tissue distribution of pigmentation including skin, fur, eyes, points, and foot pads. The overall impact of insulators is to reduce the number of transgenic founders required in order to identity animals with an appropriate expression level and tissue distribution.

Micro-SAXS and force/strain measurements during the tensile deformation of single struts of an elastomeric polyurethane foam

A microdeformation stage based on a piezoelectric crystal actuator capable of measuring the force applied to micrometre-sized polymeric samples is described. Laboratory force/strain measurements on a single strut of an elastomeric polyurethane foam have been conducted for the first time. The device has also been used on the microfocus beamline at the European Synchrotron Radiation Facility to collect microbeam small-angle X-ray scattering data simultaneously with strain and force measurements during the time-resolved tensile deformation of a single strut of elastomeric polyurethane foam.

Identification of novel L1CAM mutations using fluorescence-assisted mismatch analysis

The L1CAM gene, which is located in Xq28 and codes for a neuronal cell adhesion molecule, is involved in three distinct conditions: HSAS (hydrocephalus-stenosis of the aqueduct of Sylvius), MASA (mental retardation, aphasia, shuffling gait, adductus thumbs), and SPG1 (spastic paraplegia). Molecular analysis of the L1CAM gene is labor-intensive because of the size of the coding region, which is fragmented in numerous exons, and because of the great allelic heterogeneity and distribution of the mutations. The FAMA (fluorescent assisted mismatch analysis) method combines the excellent sensitivity of the chemical cleavage method for scanning PCR fragments larger than 1 kb and the power of automated DNA sequencers. In order to optimize this method for L1CAM, we divided the gene into nine genomic fragments, each including three to four exons. These fragments were PCR-amplified using nine sets of primers containing additional rare universal sequences. A second-stage PCR, per formed with the two dye-labeled universal primers, allowed us to generate 1-kb-labeled fragments, which were then submitted to the chemical cleavage analysis. Among 12 French families with HSAS and/or MASA, we identified nine distinct L1CAM mutations, seven of which were novel, and an intronic variation. This study demonstrates that FAMA allows rapid and reliable detection of mutations in the L1CAM gene and thus represents one of the most appropriate methods to provide diagnosis for accurate genetic counseling in families with HSAS, MASA, or SPG1.

Antiretroviral therapy may improve sensory function in HIV-infected patients: a pilot study

OBJECTIVE

To evaluate thermal and nociceptive function in a prospective, longitudinal study of 49 consecutive HIV-1-infected patients before and at 1, 4, and 8 months after initiation of highly active antiretroviral therapy.

METHODS

Quantitative assessments of thermal perception thresholds for warmth (dWT), cold (dCT), and heat pain (HPT) were performed. CD4+ cell levels in blood and HIV-1 RNA levels in plasma were determined. Depending on the virologic response to treatment, the patients were divided into two groups: responders (37 of 49, 76%) and nonresponders (12 of 49, 24%).

RESULTS

Before treatment, impairment of dWT was found in 26 of 49 patients, of dCT in 33 of 49 patients, and of HPT in 19 of 49 patients. Improvements of perception thresholds for dWT (p < 0.0001), dCT (p < 0.001), and HPT (p < 0.01) were observed after 8 months of treatment in the responder group but not in the nonresponders. Within the responder group, improved thermal perception thresholds was associated with higher pretreatment CD4+ levels than in patients without improvement.

CONCLUSIONS

Virologically successful antiretroviral combination therapy of HIV-1-infected patients has a capacity to improve function of the thermal and nociceptive systems, especially in patients with less advanced immunodeficiency.

Differences in young adult psychopathology among drug abstainers, experimenters, and frequent users

Shedler and Block offered the provocative proposal that individuals who experiment with drugs are psychologically healthier than either those who abstain completely or those who are frequent users. Not all studies have come to such conclusions, however. In an effort to specify under what conditions Shedler and Block's conclusions might hold, the present study examined three groups of drug users (abstainers, experimenters, frequent users) classified according to three different criteria: (a) marijuana use at age 20; (b) alcohol use during 10th grade; and (c) alcohol use at age 20. The three groups were compared at age 20 in terms of personality, deviant behavior, and psychopathology. The results revealed that abstainers were never more psychologically impaired, and were occasionally healthier, than experimenters. Frequent users of marijuana were consistently more imparied than both the abstainers and experimenters, in terms of both internalizing and externalizing disorders. Classification according to marijuana use appeared to be more related to psychopathology than did classification according to alcohol use.

Drastic reduction of a filarial infection in eosinophilic interleukin-5 transgenic mice

In order to establish the role of eosinophils in destroying parasites, transgenic mice have been used in experimental helminthiases but not in filariasis. Litomosoides sigmodontis offers a good opportunity for this study because it is the only filarial species that completes its life cycle in mice. Its development was compared in transgenic CBA/Ca mice overexpressing interleukin-5 (IL-5) and in wild-type mice following subcutaneous inoculation of 40 infective larvae. An acceleration of larval growth was observed in the IL-5 transgenic mice. However, the recovery rate of adult worms was considerably reduced in these mice, as evidenced 2 months postinoculation (p.i.). The reduction occurs between days 10 and 30 p.i. in the coelomic cavities. As early as day 10, spherical aggregates of eosinophils and macrophages are seen attached on live developing larvae (always similarly localized on the worm) in both wild-type and transgenic mice. However, on day 60 p.i., granulomas were found in the transgenic mice only, probably because of the higher density of eosinophils. Furthermore, on day 30 p.i., young filariae are seen trapped in granulomas, some of them surrounded by Splendore-Hoeppli deposits, which illustrates the release of the major basic protein by eosinophils. The high protection rate obtained (65%) is similar to that observed previously in BALB/c mice following vaccination with irradiated larvae. Both protocols have a common factor, the high production of IL-5 and eosinophilia. However, protection occurs later in primary infected transgenic mice because specific antibodies are not yet present at the time of challenge.

Cytotoxic effects of topotecan combined with various active G2/M-phase anticancer drugs in human tumor-derived cell lines

Topotecan (TPT) is a DNA-Topoisomerase I poison that exhibits antitumor activity. TPT, like other DNA-damaging agents, arrests or delays cell cycle progression during S- and G2-phase in a wide variety of tumor-derived cell lines. Particularly, the G2-arrest gives time for the cell to repair its DNA lesions prior to starting a new cell cycle. Based on these observations, we assessed the interaction between TPT and G2/M-active agents in p53-mutated cell lines of diverse origin in order to achieve cell toxicity. Two short-term sequential schedules were administered (TPT --> G2/M-active drug at the interval of greatest TPT-induced G2/M-phase cell arrest, and G2/M-active drug --> TPT), in three human tumor-derived cell lines with proven sensitivity to the following drugs: Bleomycin in HEp-2 (squamous larynx carcinoma); Docetaxel in SKBr-3 (breast adenocarcinoma); Etoposide in NCI-H23 (non-small-cell lung cancer). Our results show that: 1) Sequential TPT --> G2/M-active drugs are synergistic when administration overlapped the maximum percentage of TPT-induced G2/M-phase cell arrest interval in all three mutated p53 cell lines; 2) the reverse sequential schedule (G2/M-active drug --> TPT) was antagonistic, and being only additive for Etoposide --> TPT association. In conclusion, our findings further support the potential cytotoxic role of TPT in combination with other active drugs when the correct schedule of administration is applied. In addition, they provide a rationale for new applications in clinical trials using short-term sequential TPT --> G2/M-active drugs.

Effect of composition of ruminally-infused short-chain fatty acids on net fluxes of nutrients across portal-drained viscera in underfed ewes

Four ewes, each fitted with a rumen cannula and with catheters in the mesenteric artery and portal and mesenteric veins, received continuous intrarumen infusions of water or of short-chain fatty acids (SCFA). SCFA infusions were isoenergetic (83 kJ/h) and provided rumen molar proportions (acetate:propionate:butyrate) of 70:20:10, 50:40:10 or 50:20:30. The rumen SCFA production rate with the basal diet was 90.0, 23.1 and 8.8 mmol/h for acetate, propionate and butyrate respectively. Portal net fluxes indicated that 74, 67 and 22-30% of infused acetate, propionate and butyrate respectively, reached the portal vein. Portal net release of beta-hydroxybutyrate increased with SCFA infusions, irrespective of the amount of butyrate infused. Portal net release of lactate decreased with high-butyrate infusion. Portal net uptake of glucose increased with the SCFA infusions. In ewes infused with water, a portal net uptake of total amino acids (AA) was observed. SCFA infusions decreased the uptake of nonessential AA (glutamate, glycine, but not glutamine) and increased the net release of tyrosine and essential AA (isoleucine, leucine). Portal net fluxes of AA were similar with both high-acetate and high-propionate infusions. Lower net uptake of glutamine and net release of most essential AA and some nonessential AA were observed with the high-butyrate infusion. Energetic summation of portal net release was not significantly different between the three SCFA infusions, although it tended to be lower with high-butyrate infusion. This may be related to the higher trophic effect of butyrate on the digestive mucosa.

Could repeat prescriptions identify patients needing extended medical review? An exploratory study

INTRODUCTION

New Medicare Benefit Schedule care planning items require general practitioners (GPs) to identify their patients with chronic medical conditions and multidisciplinary care needs. This paper investigates the use of long term repeat prescriptions to identify general practice patients who meet these criteria.

METHODS

Twenty-nine GPs in urban, rural and inner city locations recruited 10 consecutive patients on repeat prescriptions for 12 months for medical (not primarily psychiatric) conditions. These patients reported their disease, service and morbidity (SF-36) profiles. GP attender profiles were compared with chronic disease self help group members (n = 44), an ACT community sample (n = 555) and a national GP consultation survey sample (n = 31,575).

RESULTS

GP patients reported common chronic disease profiles, high levels of specialist, hospital and medication usage, with infrequent use of allied health professionals and self help groups. They reported considerable physical and psychosocial morbidity comparable to or worse than other groups.

DISCUSSION

GP patients requesting repeat prescriptions may have substantial physical, psychological and social needs that might be met using a multidisciplinary team approach with allied health professionals and self help groups.

CONCLUSION

GPs can use long term repeat prescriptions to identify a chronic disease cohort who could benefit from health care planning under the new Medicare Benefit Schedule funding arrangements.

[Quantitative evaluation of sharing practices of materials at risk for infectious virus contamination by intravenous opiate users seeking treatment--application of the RAB(Risk for AIDS Behavior) self-administered questionnaire]

The objective of this study was to quantify the occurrence of AIDS risk related sharing activities in i.v. opiate users seeking treatment using a self administered questionnaire. Subjects were recruited among first time consultants of an outpatient clinic and assessed using the Risk for AIDS Behavior questionnaire (RAB), a self administered questionnaire that assesses both needle-sharing and unprotected sexual activity; the Beck Depression Inventory (BDI) a self administered questionnaire that assesses depressive symptoms; and the Addiction Severity Index (ASI), a 45-min, structured interview that provides assessments of problem severity in seven functional areas commonly impaired among drug abusers. Among the 102 patients who came in for treatment, all 66 subjects reporting i.v. drug abuse agreed to participate. The study was based on the data collected from these 66 subjects of whom 49 were males (74%) and mean age +/- SD was 31 +/- 5. Fifty-eight-percent of theses subjects reported having shared needles or related paraphernalia over the past 6 months. Despite informational campaigns on the risks of sharing and despite the well spread knowledge of such a risk, most i.v. opiate users seeking treatment report having shared at least once over the previous 6 months.

Cerebrospinal fluid penetration and pharmacokinetics of vancomycin administered by continuous infusion to mechanically ventilated patients in an intensive care unit

Cerebrospinal fluid (CSF) penetration and the pharmacokinetics of vancomycin were studied after continuous infusion (50 to 60 mg/kg of body weight/day after a loading dose of 15 mg/kg) in 13 mechanically ventilated patients hospitalized in an intensive care unit. Seven patients were treated for a sensitive bacterial meningitis and the other six patients, who had a severe concomitant neurologic disease with intracranial hypertension, were treated for various infections. Vancomycin CSF penetration was significantly higher (P < 0.05) in the meningitis group (serum/CSF ratio, 48%) than in the other group (serum/CSF ratio, 18%). Vancomycin pharmacokinetic parameters did not differ from those obtained with conventional dosing. No adverse effect was observed, in particular with regard to renal function.

Light's criteria revisited: consistency and comparison with new proposed alternative criteria for separating pleural transudates from exudates

OBJECTIVES

The first objective was to assess the diagnostic value of new biochemical criteria proposed to discriminate pleural transudates from exudates and to compare their efficiency with those of Light's criteria. The second objective of the study was to assess the interstudy variability of the parameters repeatedly determinated in two different groups of patients with pleural effusion.

PATIENTS AND METHODS

We recorded clinical characteristics and final diagnoses and measured pleural fluid (PF) and serum levels of protein, LDH, cholesterol and cholinesterase of 243 patients with pleural effusion.

RESULTS

Sixty-one (25%) pleural effusions were transudates and 182 were exudates. The sensitivity (99%) and accuracy (96%) of Light's criteria were higher than those of the other criteria tested, although the differences with those of the PF LDH-cholesterol combination (96 and 93%) did not show statistical significance. Pleural LDH concentration was the criterion with the highest specificity (95%), being significantly higher (p < 0.05) than that of Light's criteria. The sensitivity, specificity and accuracy of most criteria tested did not vary when compared with those obtained in a study performed 5 years previously.

CONCLUSIONS

Light's criteria remain the criteria of choice for segregating exudates from transudates. Based on cost-efficiency reasons, the PF LDH-cholesterol combination appears as an alternative. Because both sets of criteria misdiagnose a substantial percentage of transudates, exceptions based on good clinical judgment and the complementary use of a more specific criterion, as the PF concentration of LDH, must be considered.

Cellular localisation of HHV-8 in Castleman's disease: is there a link with lymph node vascularity?

AIMS

Human herpesvirus 8 (HHV-8) has been identified in multicentric Castleman's disease and in angioimmunoblastic lymphadenopathies. However, the presence of the virus does not necessarily indicate an aetiological role in these conditions. This study investigates the cell types infected by HHV-8 in Castleman's disease and examines the correlation between HHV-8 and Castleman's disease lymph node angiogenesis.

METHODS

Sixteen formalin fixed, paraffin wax embedded samples from patients with Castleman's disease (six multicentric, 10 solitary) were examined for the presence of HHV-8 using the polymerase chain reaction (PCR), non-isotopic in situ hybridisation, PCR in situ hybridisation (PCR-ISH), and real time quantitative TaqMan PCR to HHV-8 open reading frame 26 (ORF-26), and viral (v)-cyclin encoding regions. Vascularity was assessed using CD34, CD31, and factor VIII immunocytochemistry, and lymph nodes were scored as "low" or "high".

RESULTS

Five multicentric Castleman's disease and two solitary Castleman's disease biopsies were positive for HHV-8. HHV-8 was identified in approximately 10% of intranodal B lymphocytes, in endothelial cells, and in subcapsular spindle cell proliferations. The copy number of HHV-8 was low at 10-50 copies/1000 cells. The highest copy number was in subcapsular spindle cells. There was no correlation between vascularity score and HHV-8 status.

CONCLUSION

The preferential localisation of HHV-8 in subcapsular spindle cell proliferations (where early intranodal Kaposi's sarcoma initiates) and endothelial cells in Castleman's disease might finally explain the link between intranodal Kaposi's sarcoma and Castleman's disease.

High frequency in esophageal cancers of p53 alterations inactivating the regulation of genes involved in cell cycle and apoptosis

Somatic mutations of the tumor suppressor gene p53 have been frequently detected in esophagal cancers, but their biological significance remains to be established. The tumor suppressor activity of p53 results in part from its ability to transactivate genes involved in the cell cycle and apoptosis, such as p21, bax and PIG3, and some p53 mutations may have a differential effect on the transactivation of these target genes. We developed yeast strains in which the activation by wild-type p53 of reporter plasmids containing p53 binding sites present within these target genes induces a change in the color of the colonies (red/white). Using these strains, we analyzed 56 esophageal cancers from patients residing in Normandy, France, a high incidence geographic area. Forty-seven tumors (84%), scored as mutant with the p21, bax and PIG3 reporter strains and in most of the cases (76%), the percentage of red colonies suggested that both p53 alleles were inactivated. Sequencing analysis allowed the identification of a p53 mutation in each positive sample, and the spectrum of mutations was in agreement with the etiological role of tobacco and alcohol. These results confirm the high frequency of biallelic p53 mutations in esophageal carcinoma and strongly suggest that their biological consequence is the complete alteration of the transactivation of genes involved in the cell cycle and apoptosis, which indicates that p53 alteration is a key event in esophagus carcinogenesis.

Setting up a pain management programme. The Ayrshire experience

A controlled trial of an outpatient cognitive behavioural pain management programme for sufferers of non-cancer chronic pain is described. A multidisciplinary team set up a programme of ten half day sessions for groups of ten to fourteen patients aiming to improve activity levels and control over pain; to reduce maladaptive pain behaviours and drug intake; to mitigate negative mood; to modify unhelpful beliefs and to maintain treatment gains by operant and cognitive methods. Self report questionnaires were employed before and six weeks, six months and one year after the programme. Fifty-eight patients entered the study group and 39 patients completed the programme and initial follow up with further attrition in long term follow up. There were no changes in the waiting list control group of twelve subjects but the study group made significant short and long term improvements in pain severity, activity levels, mood, coping and experienced fewer catastrophizing thoughts.