Biomedical subjects

C Meyer

Publications and source records attributed to C Meyer.

At least 109 records · Page 6Linked to original sources

PubMed2001

Production of (4)(double Lambda)H hypernuclei.

An experiment demonstrating the production of double-Lambda hypernuclei in (K(-),K(+)) reactions on (9)Be was carried out at the D6 line in the BNL alternating-gradient synchrotron. The technique was the observation of pions produced in sequential mesonic weak decay, each pion associated with one unit of strangeness change. The results indicate the production of a significant number of the double hypernucleus (4)(double Lambda)H and the twin hypernuclei (4)(Lambda)H and (3)(Lambda)H. The relevant decay chains are discussed and a simple model of the production mechanism is presented. An implication of this experiment is that the existence of an S = -2 dibaryon more than a few MeV below the double Lambda mass is unlikely.

Journal Article↗

PubMed2001

Mutational and radiographic analysis of pulmonary disease consistent with lymphangioleiomyomatosis and micronodular pneumocyte hyperplasia in women with tuberous sclerosis.

Lymphangioleiomyomatosis (LAM) and multifocal micronodular pneumocyte hyperplasia (MMPH) produce cystic and nodular disease, respectively, in the lungs of patients with tuberous sclerosis. The objective of this study was to prospectively characterize the prevalence, clinical presentation, and genetic basis of lung disease in TSC. We performed genotyping and computerized tomographic (CT) scanning of the chest on 23 asymptomatic women with tuberous sclerosis complex (TSC). Cystic pulmonary parenchymal changes consistent with LAM were found in nine patients (39%). These patients tended to be older than cyst-negative patients (31.9 +/- 7.6 yr versus 24.8 +/- 11.6 yr, p = 0.09). There was no correlation between presence of cysts and tobacco use, age at menarche, history of pregnancy, or estrogen-containing medications. Three of the cyst-positive patients had a prior history of pneumothorax. Pulmonary function studies revealed evidence of gas trapping but normal spirometric indices in the cyst-positive group. All nine cyst-positive patients had angiomyolipomas (AML), which were larger (p < 0.05) and more frequently required intervention (p = 0.08) than cyst-negative patients (8 of 14 with AMLs, p < 0.05). Ten patients (43%) had pulmonary parenchymal nodules. Pulmonary nodules were more common in women with cysts (78% versus 21%, p < 0.05), and 52% of all patients had either cystic or nodular changes. TSC2 mutations were identified in all cyst-positive patients who were tested (n = 8), whereas both TSC1 and TSC2 mutations were found in patients with nodular disease. Correlation of the mutational and radiographic data revealed one pair of sisters who were discordant for cystic disease, two mother- daughter pairs who were discordant for nodular disease, and no clear association between cyst development and a specific mutational type. This prospective analysis demonstrates that cystic and nodular pulmonary changes consistent with LAM and MMPH are common in women with TSC.

Adolescent↗

PubMed2001

Synthesis of stereotriads by oxymercuration of substituted cyclopropylcarbinols.

[structure: see text] Cyclopropylcarbinol derivatives bearing an adjacent methyl-substituted stereocenter and a remote beta-hydroxy group protected as a pivalate underwent anchimerically assisted regio- and diastereoselective oxymercurations, affording after reductive demercuration, an access to stereotriads.

Cyclopropanes↗

PubMed2001

Sexual orientation and eating psychopathology: the role of masculinity and femininity.

OBJECTIVE: Previous research suggests that eating disorders are related to homosexuality in men, although links with female sexual orientation are less clear. Appearance factors have generally been implicated in this relationship. However, previous studies have failed to consider the role of femininity, even though evidence suggests that this is a more critical factor than sexual preference. The aim of this study was to consider the relationship between gender-role orientation and eating psychopathology in nonclinical men and women of different sexual orientations. METHOD: One hundred university students (40 homosexual; 60 heterosexual) completed the Bem Sex Role Inventory and the Eating Attitudes Test. RESULTS: For the group as a whole, there were links between femininity and high levels of eating psychopathology, whereas masculinity was associated with relatively healthy eating-related attitudes and behaviors. When considering the role of sexual orientation, these links were specific to homosexual men and women. CONCLUSIONS: In relation to homosexual men and women, the results support a model where femininity might be seen as a specific risk factor for eating disorders, whereas masculinity is likely to be a protective factor. Methodological and conceptual implications are discussed.

Adolescent↗

PubMed2001

Early environmental influences on restrictive eating pathology among nonclinical females: the role of temperature at birth.

OBJECTIVE: In eating-disordered populations, restrictive pathologies are associated with a higher rate of births in the spring and early summer. The reasons for this relationship are not understood. The present study of a nonclinical group aimed to determine whether there is a link between being born in warmer months and the level of restrictive pathology in later years. METHODS: The participants (N = 117) were all young adult females who were conceived and born in England. Each completed the relevant scales of the Eating Disorders Inventory and provided demographic information. Temperature at birth was determined using national meteorological records. RESULTS: Restrictive attitudes were stronger among women born during the warmer part of the year (May-August), and those attitudes were dimensionally associated with temperature at birth. Body dissatisfaction showed some of the same relationships. Neither period of birth nor temperature at birth was related to bulimic attitudes or body mass index. CONCLUSIONS: Being born during warmer months is significantly associated with restrictive eating attitudes among nonclinical females, although the link is relatively weak. Potential causal mechanisms are outlined, but further research is needed to explain this link in clinical and nonclinical groups.

Adolescent↗

PubMed2001

Environmental temperature during pregnancy and eating attitudes during teenage years: a replication and extension study.

OBJECTIVE: Among nonclinical adolescents, restrictive eating attitudes are more likely to occur among females born during warmer months. The present study aimed to replicate this finding and to extend it, considering whether such an effect is found in males and across the teenage years. In addition, the influence of temperature across the intrauterine period was considered. METHOD: The participants consisted of younger and older teenagers, all born in England. Each completed the relevant scales of the Eating Disorders Inventory and provided demographic information. Temperature across fetal development was determined using national meteorological records. RESULTS: There was a positive link between restrictive attitudes and temperature at birth among the older female group, although this replication effect did not reach significance. The same association among the older males was highly significant. The range of temperatures during fetal development also predicted later restrictive attitudes. In contrast, these effects were not replicated among the younger group, where a different pattern of effect was found (among the females only). CONCLUSION: Environmental temperature seems to have an important influence on later eating attitudes, but the pattern of influence appears to vary across development. Therefore, studies of the mechanisms behind this effect need to consider the role of gender and development, as well as the role of temperature across the period of intrauterine development.

Adolescent↗

PubMed2001

Core beliefs and bulimic symptomatology in non-eating-disordered women: the mediating role of borderline characteristics.

OBJECTIVE: To establish whether borderline personality disorder symptoms play a mediating role in the relationship between early maladaptive schemata and bulimic symptomatology, using a nonclinical sample. METHOD: Sixty-one female undergraduate students completed the Bulimic Investigatory Test, Edinburgh (BITE), the Borderline Syndrome Index (BSI), and the short form of the Young Schema Questionnaire (YSQ). RESULTS: Borderline symptoms were found to be a perfect mediator in the relationship between defectiveness/shame beliefs and bulimic symptomatology. CONCLUSIONS: A model is proposed suggesting that the functional utility of bulimic behaviors might be in counteracting the negative emotions associated with borderline symptoms.

Adolescent↗

PubMed2001

Intraoperative blood losses and transfusion requirements during adult liver transplantation remain difficult to predict.

PURPOSE: To identify preoperative factors associated with high blood losses during liver transplantation for chronic end-stage liver disease. METHODS: Four hundred and ten consecutive patients were included in this retrospective study. Blood losses were calculated, based on transfusion requirements. The population was divided into two groups: the upper quartile was defined as the high blood loss (HBL) group and the lower three quartiles as the low blood loss group. Fourteen preoperative variables were collected. Qualitative variables consisted of the type of hepatopathy, Child-Pugh's classification, sex, the surgical team's experience, previous abdominal surgery and portal hypertension. Quantitative variables were age, hemoglobin concentration Hb, platelet count, prothrombin time, activated partial thromboplastin time, fibrinogen concentration, fibrin degradation products (FDP) and euglobulin lysis time. Univariate analysis and stepwise multivariate analysis were conducted. RESULTS: Patients in the HBL group required 12 units of red blood cell or more to maintain a Hb >/= 100g*L(-1). HBL was associated with severe liver disease, previous abdominal surgery, use of a venovenous bypass and little surgical experience in orthotopic liver transplantation (OLT). In the HBL group several hemostatic parameters were more disturbed before surgery. The multivariate analysis disclosed three independent variables associated with HBL: Hb and FDP concentrations and previous upper abdominal surgery. When combined, these resulted in a high specificity (98%) but low sensitivity to predict blood loss. CONCLUSION: Despite our efforts we were unable to identify predictive risk factors of bleeding during OLT even in a homogeneous population. Centres should evaluate their practice individually in an attempt to identify patients at high risk of being transfused.

Abdomen↗

PubMed2001

Lifetime-comorbidity of obsessive-compulsive disorder and subclinical obsessive-compulsive disorder in Northern Germany.

OBJECTIVE: Inspite of the worldwide relevance of obsessive-compulsive disorder (OCD), there is a substantial lack of data on comorbidity in OCD and subclinical OCD in the general population. METHODS: German versions of the DSM-IV adapted Composite International Diagnostic Interview were administered to a representative sample of 4075 persons aged 18-64 years, living in a northern German region. RESULTS: In both genders, high rates of comorbid depressive disorders were found in OCD and subclinical OCD, whereas somatoform pain disorder was only associated with OCD. In female subjects, OCD was additionally associated with social and specific phobias, alcohol, nicotine and sedative dependence, PTSD and atypical eating disorder. CONCLUSION: Due to low comorbidity rates, subclinical OCD seems to represent an independent syndrome not restricted to the presence of other axis-I diagnoses. Comorbidity patterns show a disposition to anxiety and to depressive disorders in OCD and subclinical OCD. A broad association with obsessive-compulsive spectrum disorders could not be confirmed in our general population sample.

Adult↗

PubMed2001

Transcription of mutS- and mutL-homologous genes during meiosis in Saccharomyces cerevisiae and identification of a regulatory cis-element for meiotic induction of MSH2.

We have analysed the levels of mRNA transcripts of the mutS- and mutL-homologous genes of the yeast Saccharomyces cerevisiae during the course of meiosis, by quantitative RT-PCR. We found that all mutS homologues (MSH1-6) were induced during meiosis, whereas no evidence for regulation of the mutL homologues (PMS1, MLH1-3) was obtained. Temporal expression patterns indicative of co-regulation were observed for the gene pairs MSH4/MSH5 and MSH2/ SPO11. Sequence comparisons of the 5' flanking regions revealed similar sequence stretches in the respective gene pairs, which may constitute regulatory elements. Similar sequences were also found in the 5' flanking regions of the pairs MSH1/MSH3 and MSH1/MSH6. Upstream of MSH2 three closely spaced sequences similar to UASH elements were found, which - surprisingly are located within the coding region of SPO21. Deletion of these elements resulted in loss of meiotic induction of MSH2. Genetic analysis of homozygous deletion mutants did not reveal any differences from wild type with respect to genetic distance estimates, aberrant segregation, or suppression of homoeologus recombination in an interspecies cross with Saccharomyces paradoxus.

Adenosine Triphosphatases↗

PubMed2001

Long-term recurrence after laparoscopic surgery of inguinal hernias.

Laparoscopic treatment of inguinal hernias has expanded rapidly during the last decade. Several studies have evaluated the early results of this technique, and the rate of recurrence was estimated less than 5% with a range from 0.5% to 10%. The long-term recurrence after such treatment is still not well known. This study reports the 2 year follow-up of laparoscopic treatment of 236 inguinal hernias (220 patients) from January 1996 to December 1997. All patients were contacted by telephone, 196 (90%) (193 men and 3 women) were examined by a senior surgeon. The average time from operation to examination was 34 months (range 20-42 months). We observed a 15% recurrence rate (35 hernias in 34 patients) of which 5% (12 cases) were symptomatic but 10% (23 cases) were totally asymptomatic and diagnosed on clinical examination. The postoperative inguinal haematoma and the physical activity of the patients seem to predispose the recurrence. Chronic pain was rarely observed in this study.

Adult↗

PubMed2001

Neuropeptide Y Y2 receptor signalling mechanisms in the human glioblastoma cell line LN319.

Neuropeptide Y (NPY) regulates neurotransmitter release through activation of the Y2 receptor subtype. We have recently characterized a human glioblastoma cell line, LN319, that expresses exclusively NPY Y2 receptors and have demonstrated that NPY triggers transient decreases in cAMP and increases in intracellular calcium responses. The present study was designed to further characterize calcium signalling by NPY and bradykinin (BK) in LN319 cells. Both agonists elevated free intracellular calcium ([Ca(2+)](i)) without soliciting calcium influx. NPY appeared to activate two distinct signalling cascades that liberate calcium from thapsigargin- and ryanodine-insensitive compartments. One pathway proceeded through phospholipase C (PLC)-dependent phosphatidylinositol turnover, while the other triggered calcium release through a so far unidentified mediator. Part of the response was sensitive to pertussis toxin (PTX) under conditions where the toxin totally abolished the NPY-mediated effects on cAMP. The calcium release induced by BK on the other hand was largely PTX-insensitive, PLC-dependent, and from both thapsigargin- and ryanodine-sensitive stores. Following stimulation with NPY, subsequent [Ca(2+)](i) responses to NPY were strongly depressed. Partial heterologous desensitization occurred, when BK was used as the first agonist, whereas NPY had no effect on a subsequent stimulation with BK. These data suggest that NPY-induced calcium mobilization in LN319 cells involves two different G proteins and signalling mediators, and a hitherto unidentified calcium compartment. Homologous desensitization of NPY signalling might be explained by receptor-G protein uncoupling, while heterologous desensitization by BK could be the result of either transient depletion or inhibition of a mediator in the calcium signalling cascades activated by NPY.

Animals↗

PubMed2001

Anticonvulsant properties of the methanolic extract of Cyperus articulatus (Cyperaceae).

The methanolic extract of rhizomes of Cyperus articulatus, a plant used in traditional medicine in Africa and Latin America for many diseases, possesses anticonvulsant activity in mice. This extract protected mice against maximal electroshock (MES)- and pentylenetetrazol (PTZ)-induced seizures. It also delayed the onset of seizures induced by isonicotinic acid hydrazide and strongly antagonized N-methyl-D-aspartate-induced turning behavior. The ED(50) for protection against seizures was 306 (154-541) mg/kg intraperitoneally (i.p.) for the PTZ test and 1005 (797-1200) mg/kg i.p. for the MES test. The ED(50) of methanolic extract against N-methyl-D-aspartate-induced turning behavior was 875 (623-1123) mg/kg i.p. C. articulatus L. methanolic extract protected 54% of mice from seizures induced by strychnine at the dose of 1000 mg/kg i.p. but had no or a moderate effect only against picrotoxin- or bicuculline-induced seizures. With these effects, the rhizome of C. articulatus L. possesses anticonvulsant properties in animals that might explain its use as a traditional medicine for epilepsy in Africa.

Animals↗

PubMed2001

[Chronic pelvic pain. Another diagnostic and therapeutic approach].

Chronic pelvic pain (CPP) is a frequent and difficult problem because despite the quality and diversity of diagnostic procedures no relevant etiology will be found in 30 to 40% of all cases. Psychologic and psychotherapeutic counselling is than usually proposed and usually not well accepted. A different approach can now be proposed according to a new semeiologic overall. In many cases the pain dominant is not visceral but parietal. The pelvic envelope is actually more painfull than the pelvic content. In these cases one can evoke the diagnosis of pelvic fibromyalgia and this is quite similar to classic fibromyalgia. This pelvifibromyalgia can be quantified with an algometric index. This form of pain actually is the somatisation of a past and difficult issue which will be very slowly and progressively revealed in the realm of a multidisciplinary and simultaneous physical and psychological approach. In the majority of cases these women have occurred physical, moral or sexual trauma inflicted by family members or a third party. Taking in account the physical dimension of body pain at the same time as psychotherapy will considerably enhance the efficiency of treatment. In our experience 70% of all women will be cured using this new approach.

Acupuncture Therapy↗

PubMed2001

Pancreatic metastasis of alveolar soft-part sarcoma: a case report and review of the literature.

Alveolar soft-part sarcoma is a rare tumour. Patients commonly present with distant metastases both at the time of diagnosis and late in the course of disease. We present a case of pancreatic metastasis, occurring more than six years after diagnosis. Treatment consisted in subtotal pancreatoduodenectomy with pylorus resection. Both specific patterns of relapse and treatment opportunities of this uncommon feature are discussed.

Adult↗

PubMed2001

Establishment of the B cell precursor acute lymphoblastic leukemia cell line MUTZ-5 carrying a (12:13) translocation.

Continuous leukemia-lymphoma cell lines are important research tools, in particular as starting material for the cloning of recurrent translocations. In 1998, we established the continuous leukemia cell line MUTZ-5 and its two simultaneous sister cell lines MUTZ-6 and MUTZ-7. The primary specimen was obtained from the peripheral blood of a 26-year-old man with B cell precursor acute lymphoblastic leukemia at relapse carrying a t(12;13). The immunoprofile of MUTZ-5 corresponds to that of a precursor B cell. The immunoglobulin heavy chain gene was found to be rearranged. Despite receptor expression, none of the cytokines examined enhanced proliferation; several cytokines had significant inhibitory effects. Giemsa-banding cytogenetics showed the following karyotype which was identical in all three sister cell lines: 45<2n>X, -Y, t(12;13)(p12;q13-14). The karyotype and DNA fingerprinting confirmed the malignant nature and the authenticity of the cell line, excluding cross-contamination with other cells. MUTZ-5 represents a new unique leukemia B cell line; its scientific significance lies in the t(12;13).

Adult↗

PubMed2001

Factors influencing remission from alcohol dependence without formal help in a representative population sample.

AIMS: To analyse factors related to remission without formal help by using a representative sample and standardized instruments. DESIGN: Two groups of untreated alcohol-dependent subjects were compared. SETTING: General population survey. PARTICIPANTS: Thirty-two subjects fully remitted without formal help (NFH) and 26 current alcohol-dependent individuals (CAD) according to DSM-IV drawn from a representative general population sample in northern Germany (response rate: 70.2%, n = 4075). MEASUREMENTS: Data focusing on the 2 years prior to remission from NFH were compared with past-year data from CAD. Groups were compared on variables found to be associated with remission without formal help in previous research. FINDINGS: Logistic regression analysis revealed that individuals remitted from alcohol-dependence without formal help reported a higher non-physiological severity of alcohol dependence, less social pressure to quit drinking and more incidents of driving while intoxicated. Furthermore, they tended to report more satisfaction with work and financial situation and were more likely to live in a stable partnership. CONCLUSIONS: Findings support the concept of psychosocial resources as important enabling factors in remission from alcohol dependence without formal help. Implications for brief interventions are discussed.

Adolescent↗

PubMed2001

The association between degree of nicotine dependence and other health behaviours. Findings from a German general population study.

BACKGROUND: To investigate the association between degree of nicotine dependence and unhealthy nutrition, lack of physical activity, and hazardous alcohol drinking. METHODS: Data with respect to cigarette and alcohol consumption, nutrition, and physical activity was collected in a representative general population sample (N = 4.075). RESULTS: Smokers with high compared to moderate and low degrees of nicotine dependence consume unhealthy foods more frequently, report less physical activity and more hazardous alcohol drinking. CONCLUSION: From a public health point of view, special secondary preventive interventions for smokers with high nicotine dependence and additional unhealthy behaviours are necessary.

Adolescent↗