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Biomedical subjects

B Martin

Publications and source records attributed to B Martin.

At least 523 records · Page 29Linked to original sources
PubMedDate not supplied

Mouse chromosomes 4 and 13 are involved in beta-carboline-induced seizures.

beta-Carbolines, such as methyl beta-carboline-3-carboxylate (beta-CCM), attach to the benzodiazepine receptors in the brain, but have effects completely opposite to those of benzodiazepines: beta-CCM is a convulsant at high doses, an anxiogenic at moderate doses, and enhances learning at low doses. The aim of this work was to detect some of the chromosomal segments involved in the regulation of beta-CCM-induced seizures. The method used was a derivation of the classical use of linkage-testing strains. We tested several strains and some of their intercrosses and back-crosses. For two of these strains, we obtained significant results showing that genes located on chromosomes 4 and 13, provisionally termed respectively Bis1 and Bis2, were involved in the regulation of beta-carboline-induced seizures. Testing of these two strains with two other convulsant agents (pentylenetetrazol, which acts at the picrotoxine site of the GABA receptor complex, and strychnine, which acts at the glycinergic receptor) provided evidence that the genes implicated are not involved in general seizure processes but specifically in beta-CCM-induced seizures.

Animals↗
PubMedDate not supplied

Is a general women's health promotion program as effective as an HIV-intensive prevention program in reducing HIV risk among Hispanic women?

OBJECTIVE: This study aimed to assess whether participants in an HIV-intensive prevention program and participants in a general women's health promotion program reported greater HIV risk-reduction than participants in a wait-list control group immediately following program participation and at three-month follow-up. METHODS: The authors studied 162 Hispanic women ages 18 to 35 years, most of them immigrants. Three-fourths of the sample (74%) reported earning less than $800 a month, 29% did not have a high school degree, and 90% had children. Data were gathered through surveys at baseline, at intervention completion, and at three-month follow-up. Information was collected on sociodemographics, HIV risk factors, and risk behaviors. Crude and adjusted (for demographics and dose) logistic regression analyses were used to assess program effects on participants' risk reduction. RESULTS: Crude logistic regression analyses reveal that both programs resulted in increased condom use at post-test and follow-up. Only participants in the HIV-intensive prevention program reported increased safer sex negotiation at post-test and follow-up, however, and only participants in the women's health promotion program reported increased HIV testing at post-test. CONCLUSION: Both interventions increased condom use. The HIV-intensive prevention program appeared to be more effective in promoting safer sex negotiation, and the women's health promotion program appeared more effective in promoting HIV testing. The findings suggest that both approaches may be viable ways to package HIV prevention for short-term behavior change in this population.

AIDS Serodiagnosis↗
PubMedDate not supplied

Enhanced therapeutic potential of adoptive immunotherapy by in vitro CD28/4-1BB costimulation of tumor-reactive T cells against a poorly immunogenic, major histocompatibility complex class I-negative A9P melanoma.

Costimulation plays a critical role in T-cell activation and amplification of anti-tumor immunity. Although CD28 engagement triggers an early activation signal, activation-induced 4-1BB molecule on T cells transmits a crucial signal for further expansion and maturation of effector cells. In this report, the authors show that costimulation through CD28 and 4-1BB pathways synergistically enhances the therapeutic efficacy of T cells from tumor-draining lymph nodes. Intravenous adoptive transfer of costimulated T cells into mice bearing disseminated micrometastasis of a poorly immunogenic, major histocompatibility complex class I-negative A9P melanoma results in a 60% cure rate. Autopsy of mice that died after unsuccessful treatment revealed tumor growth in the liver, spleen, and skin with minimal or no evidence of pulmonary disease. In contrast, mice that received no treatment or noncostimulated T cells had massive pulmonary tumors, suggesting that adoptively transferred T cells are less effective against growth of extrapulmonary tumors. These results show that costimulation of tumor-draining lymph node T cells through CD28 and 4-1BB increases their potential for cancer immunotherapy and suggests that improper trafficking of tumor-reactive T cells to extrapulmonary sites must be improved to enhance clinical efficacy.

4-1BB Ligand↗
PubMedDate not supplied

Transverse relaxation time values in MR imaging of normal breast during menstrual cycle.

Magnetic resonance (MR) imaging of the breast has shown promise in the diagnosis of breast lesions. In prior studies the time of MR examination in the menstrual cycle was not taken into account. If alterations in transverse relaxation time (T2) values of ductal tissue did occur during the menstrual cycle, they would have a significant bearing on the timing of MR studies of the breast. This study demonstrated no apparent alteration in T2 values during the menstrual cycle of normal young volunteers.

Adult↗
PubMedDate not supplied

MR imaging of intramural duodenal hematoma.

The magnetic resonance (MR) appearance of a case of intramural duodenal hematoma is described and compared with CT findings. Due to the paramagnetic effects of iron, the hematoma was more clearly visualized by MR.

Adolescent↗
PubMedDate not supplied

MR imaging of anterior sacral meningocele.

The magnetic resonance appearance of a case of an anterior sacral meningocele is described and the particular advantages of this technique, compared with other radiological studies, are considered.

Adult↗
PubMedDate not supplied

Diffuse cavernous hemangioma of the rectosigmoid colon: imaging findings.

Diffuse cavernous hemangioma of the rectosigmoid colon (DCHR) is an uncommon disease that affects mainly young adults. As the main symptom is non-specific chronic rectal bleeding, the clinical diagnosis is difficult and often delayed. In this essay, we illustrate the imaging features of DCHR, including plain radiograph, barium enema, CT and MR study, and echoendoscopy. Pitfalls in diagnosis and the role of imaging study in the diagnosis, in the preoperative staging, and in the follow-up of the patients are defined.

Adolescent↗
PubMedDate not supplied

Office removal of tibial external fixators: an evaluation of cost savings and patient satisfaction.

OBJECTIVES: To evaluate the efficacy and patient satisfaction of office removal of tibial external fixators and to compare the cost of this procedure with the cost of removal of fixators in the operating room. DESIGN: A visual analog scale (VAS) and a questionnaire were answered by all patients after office external fixator removal. The treatment, complications, and costs were compared with those of patients having external fixator removal in the operating suite. SETTING: An urban orthopaedic trauma office with a Level I trauma center. PARTICIPANTS: Two similar groups of patients; thirty fixators removed in the office and twenty-nine fixators removed in the operating room. INTERVENTION: Office or operating room removal of tibial external fixators and application of a sterile dressing. A visual analog scale was answered by those patients who had office removal. MAIN OUTCOME MEASUREMENTS: Patient satisfaction and pain rating (VAS) with office removal of external fixators. Comparison of costs, infections, time in fixator, and surgical interventions between the office and operating room groups. RESULTS: Group I had thirty fixators (twenty-nine half-pin fixators) removed in the office. Group II had twenty-nine fixators removed in the operating room. Duration of time in the frame was not statistically different. Antibiotic usage during the fixator treatment period was 69 percent in both groups. On the visual analog scale, twenty-four members (80 percent) of the office fixator removal group rated the pain during removal as less than 25 percent of maximal, including nine (30 percent) who rated the removal as causing no pain. Cost analysis revealed an average cost of $248 for the office group versus $2,160 for the operating room group (p < 0.001). CONCLUSIONS: Due to the cost savings and patient satisfaction, without compromising clinical care, the office is our preferred location for tibial half-pin external fixator removal.

Adolescent↗
PubMedDate not supplied

Subjective symptomatology of asthma in an outpatient population.

Characteristics of subjective symptomatology of asthma were examined within a group of 132 adult asthma patients receiving medical care in a university-based, ambulatory clinic setting. Patients responded to 36 symptom descriptions or adjectives associated with asthma which were included in a modified version of the Asthma Symptoms Checklist (ASC). A principal components exploratory factor analysis was conducted and five factors were identified. The five factors measured 1) panic-fear, 2) airways obstruction, 3) hyperventilation, 4) fatigue, and 5) irritability. Psychometric properties of the factor scores were satisfactory. The reliabilities were high, standard deviations were large, and differences in factor mean scores conformed to clinical experience. Correlational analyses support the construct validity of the ASC, especially the panic-fear factor. An important outcome of this study was to verify the ASC factor structure in an outpatient setting. The ASC was confirmed as a valuable instrument for use in self-management programs for adults with asthma. The five ASC factors represent highly stable components of subjective symptomatology of asthma among diverse adult patient populations and geographical settings.

Adaptation, Psychological↗
PubMedDate not supplied

Analysis of B10.D2 recombinant congenic mouse strains shows that audiogenic and beta-CCM-induced seizures depend on different genetic mechanisms.

The rate of occurrence of audiogenic seizures and seizures induced by the benzodiazepine receptor inverse agonist methyl-beta-carboline-3-carboxylate (beta-CCM) were analyzed in several recombinant congenic strains of mice bred from B10.D2 and DBA/2J. Although both types of seizures have similar behavioral patterns and might involve GABAergic mechanisms, no correlation was observed between the occurrence of the two types of seizures across the strains, suggesting that these two types of seizures depend on different genetic mechanisms.

Acoustic Stimulation↗
PubMedDate not supplied

Convulsions induced by methyl beta-carboline-3-carboxylate in mice: effects of preceding saline injections.

The convulsant effects of a high (5 mg/kg intraperitoneally, i.p.) dose of benzodiazepine (BZD) receptor ligand methyl beta-carboline-3-carboxylate (beta-CCM), whether or not preceded by administration of two lower doses of beta-CCM (0.5 and 1 mg/kg i.p.) or of saline were studied in nine inbred mouse strains. In five of the strains (A/J, BALB/cBy, C3H/HeJ, CBA/H, and DBA/2J), neither saline nor preceding injections of beta-CCM had any effect on subsequent reactivity to the subsequent convulsant dose. In the other 4 strains, such injections induced either tolerance (CPB-K, NZB), or sensitization (C57BL/6J, XLII), whatever the compound subsequently administered (beta-CCM or saline). In these strains, the data rule out any tolerance or sensitization effect due to beta-CCM, but suggest that such effects could be due to injection itself.

Animals↗
PubMedDate not supplied

Worry and anxiety: is there a causal relationship?

The aim of this study was to examine the relationship between worry and anxiety and depression. Path analysis was used to estimate a nonrecursive model which describes the reciprocal causal relation between worry and anxiety. The final model fits the data well and leads to the conclusion that the association between these two constructs is not bidirectional. Indeed, we observed a significant positive effect of worry on anxiety, but no effect in the opposite direction. This result provides a supporting argument for researchers wishing to distinguish these two constructs. Moreover, depression is not directly affected by worry, but is indirectly affected through anxiety.

Adolescent↗
PubMedDate not supplied

Characterization of a human high density lipoprotein-associated protein, NA1/NA2. Identity with SP-40,40, an inhibitor of complement-mediated cytolysis.

Two peptides, NA1 and NA2, which we previously suggested to be associated with high density lipoproteins (HDLs), have been purified. Polyclonal antibodies against each peptide and a monoclonal antibody against NA2 have been used to further characterize them and their association with HDL. Immunoblotting studies revealed that the peptides form a complex of molecular mass of approximately 80 kd. Agarose gel filtration showed coelution of NA1/NA2 and apolipoprotein (apo) A-I, the structural protein of HDL. This was confirmed by fast protein liquid chromatography, which further indicated that up to 60% of NA1/NA2 was located within the lower density range of the HDL spectrum. Complementary studies with anti-apo A-I immunoaffinity columns provided evidence that at least 40% of NA1/NA2 was associated with HDL, an association easily disrupted by ultracentrifugal manipulation. Finally, partial amino acid sequences showed virtually complete homology with a recently identified protein, SP-40,40, or cytolysis inhibitor. The protein is suggested to have a powerful inhibitory effect on complement-mediated cell lysis. Our results could thus furnish an explanation for the previously observed modulating influence of HDL on complement activity.

Amino Acid Sequence↗
PubMedDate not supplied

Review of Medicare's proposed hospice eligibility criteria for select noncancer patients.

Recent events have challenged our health system to increase access to and provide high quality care for patients near the end of life. Simultaneously, Medicare is developing review policies to determine eligibility for hospice patients with select noncancer diagnoses. The purpose of this study was to determine whether the proposed policies met one of their chief goals: accurate identification of patients with a less-than-six-months prognosis. Only 35 percent of 104 patients who died within six months of admission to the hospice used for this study, LifePath Hospice, met the Medicare proposed criteria for hospice eligibility. The median and mean survival time of the sample was 14 and 30 days respectively. Based on this review, it is recommended that Medicare alter their proposed review policies and not limit access to hospice eligible patients who desire and are in need of such services.

Chronic Disease↗
PubMedDate not supplied

A simple "step-test" protocol for identifying suspected unrecognized exercise-induced asthma (EIA) in children.

The purpose of this study was to demonstrate that a simple submaximal "step-test" could be used as an exercise challenge to identify elementary school students with suspected but undiagnosed asthma. This article also describes a protocol for exercise testing that can be used in epidemiological evaluations. School age children grades 1-4 with suspected but undiagnosed asthma were identified by a 12-item questionnaire completed by a parent or guardian. Only students identified with suspected asthma by questionnaire were exercise challenged on a step-test it baseline spirometry was normal and there was no contraindication for intense aerobic activity. Possible asthma was defined as a 15% or greater decrease in FEV1 or a 25% or greater decrease in FEF25-75 from baseline at either 3 or 10 minutes. The exercise protocol included spirometry before and after stepping continuously for 5 minutes at an exercise intensity sufficient to maintain a heart rate between 150 and 200 beats per minute. Heart rate was continuously monitored throughout the exercise period. Testing was completed at school. No complications occurred during the exercise testing. Exercise testing was completed on 548 students with suspected undiagnosed asthma. Thirty students (6%) had exercise test changes in pulmonary function that met established criteria for suspecting asthma. A board-certified pediatric allergist/immunologist or private physician examined 26 of the 30 students with positive exercise testing. Asthma was diagnosed in 23 (88.89%) of these students. All students with impaired pulmonary function after exercise were able to return to class after a short period of observation. In conclusion, a simple, reproducible school-based exercise protocol can be used to identify students with suspected undiagnosed asthma.

Asthma, Exercise-Induced↗
PubMedDate not supplied

Utilization of dental services and preventive oral health behaviors among preschool-aged children from Delaware.

PURPOSE: This study evaluated factors associated with age-appropriate dental care utilization and preventive behaviors among preschool-aged children in Delaware. METHODS: In June 1994, child health questionnaires were mailed to a simple random sample of 1,005 Delaware caregivers whose children were ages 6 to 36 months. RESULTS: Only 12% of children > or = 12 months old had been to the dentist. Child's race, maternal education, maternal age, dental insurance, having a regular place for medical care, receiving information on tooth care from medical personnel, and family income were not associated with having a dental visit. CONCLUSIONS: Improving information provided to caregivers and health professionals on appropriate timing of dental services and preventive dentistry is recommended to enhance oral health for preschool-aged children.

Chi-Square Distribution↗
PubMedDate not supplied

Peritoneal macrophages from 17 alpha-ethinylestradiol-treated NMRI mice secrete transformation-specific low molecular weight proteins.

Analysis of protein secretion was performed for a macrophage-like cell line, which was established from the peritoneal cells of NMRI mice treated with 17 alpha-ethinylestradiol. The protein secretion pattern was investigated by computerized analysis of high resolution two-dimensional gel electrophoresis (2-D PAGE) and compared to that of control macrophages, intraperitoneally activated by bacterial lipopolysaccharide. The transformed cells encode a number of low molecular weight proteins (10-20 kDa), which were not observed in control cells under identical experimental conditions. In conclusion the transformation of peritoneal macrophages by 17 alpha-ethinylestradiol leads to an upregulation of polypeptides, in particular of low molecular weight proteins. A high similarity between the induced low molecular weight protein secretion by macrophages of 17 alpha-ethinylestradiol-treated and that of 2,3,7,8-tetrabromodibenzo-p-dioxin-treated mice was found.

Animals↗