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Biomedical subjects

M Jenkins

Publications and source records attributed to M Jenkins.

At least 73 records · Page 4Linked to original sources
PubMed1995

Obsessive-compulsive behaviour in children and adolescents: a cross-sectional Australian study.

OBJECTIVE: To examine the reliability of the survey form of the Leyton Obsessional Inventory-Child Version (LOI-CV), ascertain the prevalence of self-reported obsessive-compulsive behaviour together with age and sex differences and identify the most common obsessive-compulsive behaviours and their associated level of interference. METHODOLOGY: The survey form of the LOI-CV was administered to a large sample of children and adolescents attending regular schools. Participants were aged between 8 and 16 years (n = 1602). RESULTS: We found the survey instrument to have adequate internal consistency and test-retest reliability. There was an age-related decline in self-reported obsessive-compulsive behaviour and girls reported a higher level of obsessive-compulsive behaviour than boys. The most common obsessive-compulsive behaviours included: repeated thoughts or words, having trouble making decisions, having to do certain things and doing things in the exact manner and having a bad conscience. For the most part, these behaviours were associated with low levels of interference. However, for a significant minority of youth (5 to 14%), these behaviours did cause problems and significantly interfered with their lives. CONCLUSIONS: Although many obsessive-compulsive behaviours are part of normal development, they may still be problematic for some children and adolescents.

Adolescent↗
PubMed1995

Amphetamine on Rorschach measures in normal subjects.

Twenty-two normal undergraduate men were administered either d-amphetamine (0.2 mg/kg or 0.4 mg/kg) or placebo in a double-blind, counterbalanced design. The test sessions were exactly three weeks apart and included, among other measures, the Rorschach test. Rorschach anxiety and thought disorder variables were measured under drug and placebo conditions. The results suggest that amphetamine causes an increase in Rorschach anxiety indices but does not elevate Rorschach indices of thought disorder. The observed dissociation of anxiety and thought disorder on the Rorschach has implications for the role of the Rorschach in studying anxiety disorders and schizophrenic disorders.

Adult↗
PubMed1995

Test-retest reliability of the survey form of the Leyton Obsessional Inventory-Child Version.

The test-retest reliability of the survey form of the Leyton Obsessional Inventory-Child Version was examined over a 2-wk. interval. Three age groups of children participated in the study, 8- to 10-year-olds, 11- to 13-year-olds, and 14-to 16-year-olds (N = 106). For the total Obsessive scores, the test-retest Pearson correlation coefficients for the three age groups were .51, .75, and .83, respectively, which suggest that the temporal stability of the instrument is a function of age.

Adolescent↗
PubMed1994

Association between anti-human immunodeficiency virus type 1 (HIV-1) antibody-dependent cellular cytotoxicity antibody titers at birth and vertical transmission of HIV-1.

Because vertical transmission of human immunodeficiency virus type 1 (HIV-1) from mother to infant occurs in only 15%-35% of possible opportunities, natural immune defenses of the mother, fetus, or neonate may be protective against infection. The relation between antibody-dependent cellular cytotoxicity (ADCC) antibodies and HIV-1 infection was explored in 78 neonates born to HIV-infected women. More than 90% of sera had measurable ADCC titers against HIV-1IIIB. Infant titers were closely correlated with maternal titers but were independent of total IgG and total antibody reactive to the same strain in whole virus ELISA. At birth, mean ADCC antibody levels of infants or their mothers were the same for infants who were infected and those who ultimately seroreverted and remained healthy. ADCC antibody titers against HIV-1SF2 were weakly correlated with anti-HIV-1IIIB titers and did not predict protection from HIV-1 infection. High levels of anti-HIV-1 ADCC antibody at birth are not protective against vertical transmission of HIV-1.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1994

Asthma, allergy and atopy in southern Chinese school students.

In order to determine the prevalence of asthma, allergy and atopy in southern China and the relative importance of atopy and parental history in predicting asthma and allergic diseases, we carried out a cross-sectional study on 737 secondary school students aged 12-20 (492 boys, 245 girls; mean age = 16.4 years, SD = 1.8 years) in the city of San Bu, Guangdong, China. Standard questionnaires on respiratory and allergic symptoms were distributed for completion by parents with an overall response of 98.6%. Skinprick tests to common aeroallergens were performed on 647 subjects (87.8%) to determine atopic status. The prevalence (and 95% CI) of a history of hay fever, eczema, wheeze or asthma ever and wheeze in past 12 months were 1.6% (0.7-2.5), 10.4% (8.2-12.6), 1.9% (0.9-1.9) and 1.1% (0.3-1.9) respectively. Forty-nine per cent (45.2-52.9) of students had one or more positive skin tests to common aeroallergens. Amongst atopic subjects, 87.3% reacted to house dust mite (Dermatophagoides pteronyssinus) and 73.3% to cockroach. There was a close association between the degree of atopy and the prevalence of a history of wheeze (P < 0.05) but not with hay fever or eczema. After adjusting for age and sex, parental histories of hay fever, eczema and wheeze were strongly associated with the respective symptoms in the subjects (OR = 17.4 (3.2-93.9) for hay fever, 27.4 (12.7-59.0) for eczema, 79.4 (21.9-288.4) for wheeze). It is concluded that respiratory and allergic symptoms were uncommon in Chinese school students despite a high prevalence of atopy, and that parental history is more important in predicting asthma and allergy than atopy.

Adolescent↗
PubMed1993

Early detection and measurement of experimental myocardial infarcts with horseradish peroxidase.

Current methods of experimental infarct size measurement require tissue analysis several hours after the ischemic event. Electron microscopy identifies irreversibly injured myocytes early after ischemia, but cannot be used to measure myocardial infarct size. Horseradish peroxidase (HRP), a tracer protein that permeates the disrupted sarcolemma of injured myocytes, was used to determine infarct size. New Zealand White rabbits (n = 15) were subjected to 30 min coronary artery occlusion and 24 h reperfusion. Prior to euthanasia, HRP was administered intravenously. The hearts were excised, perfused with triphenyl tetrazolium chloride (TTC), and perfusion fixed. A frozen section was cut from left ventricular slices, and the brown HRP reaction product was developed with 3,3'-diaminobenzidine tetrahydrochloride and H2O2. The areas delineated by intramyocyte HRP (as a percent of the left ventricle) closely correlated with infarct size determined by conventional hematoxylin-eosin (H&E) stain and TTC (means +/- S.E.M.): 29.5 +/- 3.0% vs 27.6 +/- 2.9% vs 28.6 +/- 2.6%, respectively. The coefficient of correlation between HRP and H&E was 0.94. This method was tested for early infarct detection in rabbits subjected to 30 min coronary occlusion followed by intravenous injection of HRP and sacrifice. HRP-delineated infarcts measured 21.4 +/- 3.7% of the left ventricle, and electron microscopic examination from ischemic and non-ischemic areas was used to confirm that cells containing HRP were irreversibly injured. Thus, HRP can be used to accurately measure myocardial infarct size in experimental coronary artery occlusion and reperfusion in infarcts as early as 30 min after coronary occlusion or following 24 h of reperfusion.

Animals↗
PubMed1993

Myocardial infarct extension during reperfusion after coronary artery occlusion: pathologic evidence.

OBJECTIVES: The goal of this study was to demonstrate myocardial infarct extension during reperfusion within the same animal. BACKGROUND: Whether myocardial reperfusion can result in the extension of myocardial necrosis remains controversial. The transformation of reversibly injured myocytes into irreversibly damaged cells after reperfusion has been difficult to demonstrate pathologically. METHODS: New Zealand White rabbits (Group I, n = 10) were subjected to 30 min of coronary artery occlusion and 180 min of reperfusion. Horseradish peroxidase, a tracer protein that permeates the sarcolemma of irreversibly injured myocytes, was used to quantitate myocyte necrosis at the beginning of reperfusion. Within the same heart, infarct size was measured after 180 min of reperfusion by triphenyltetrazolium chloride (TTC) staining. In separate experiments to demonstrate the validity of the model, rabbits were subjected to 30 min of coronary occlusion, followed by intravenous infusion of horseradish peroxidase and rapid induction of death (Group II) or 30 min of occlusion, 180 min of reperfusion with horseradish peroxidase administered after 180 min of reperfusion and TTC staining after induced death (Group III). RESULTS: In Group I, infarct size at the onset of reperfusion, delineated by horseradish peroxidase, measured 45.3 +/- 2.8% of the area of risk and was significantly less than TTC-delineated infarct size after 180 min of reperfusion (59.8 +/- 3.3%, p = 0.0002). By electron microscopy, border areas within the ischemic bed demonstrated irreversibly injured horseradish peroxidase-positive myocytes adjacent to irreversibly injured horseradish peroxidase-negative myocytes, suggesting that further cell death occurred during reperfusion. In Group II, infarcts delineated by horseradish peroxidase after 30 min of coronary occlusion were similar in size to infarcts measured by this tracer in Group I. In Group III, infarcts delineated by horseradish peroxidase at 180 min of reperfusion were similar in size to infarcts measured by TTC and similar to TTC-delineated infarcts measured at 180 min of reperfusion in Group I. CONCLUSIONS: These results provide evidence that there is a subset of myocytes in border areas within the ischemic region that are viable at the beginning of reperfusion but subsequently progress to irreversible injury during the reperfusion period.

Animals↗
PubMed1993

Natural killer cytotoxicity and antibody-dependent cellular cytotoxicity of human immunodeficiency virus-infected cells by leukocytes from human neonates and adults.

In infants born to mothers infected with the human immunodeficiency virus (HIV), antibody-dependent cellular cytotoxicity (ADCC) or natural killer cytotoxicity (NKC) may either eliminate infection or ameliorate its course. We developed and standardized an assay for cytotoxicity of HIV-infected cells and studied the capacity of leukocytes from healthy neonates and adults to lyse HIV-infected cells by ADCC and NKC. The chosen target cell line, a T cell line infected with the HXB-2 clone of human T-cell lymphotrophic virus-IIIB, displayed stable surface expression of viral antigens over months of continuous culture and allowed simultaneous assessment of NKC and ADCC of effector cell populations. Conditions for optimal ADCC lysis of target cells were defined for unpurified peripheral blood mononuclear cells and purified lymphocytes and monocytes. Polymorphonuclear neutrophils from healthy adults and neonates exhibited low activity in ADCC of HIV-infected targets. Lymphocytes and monocytes from adults were found to differ in antibody dependence, kinetics, and sensitivity to latex inhibition for ADCC-mediated lysis of HIV-infected targets. Peripheral blood mononuclear cells of healthy neonates and adults displayed equivalent capacity to mediate NKC of HIV-infected targets. However, neonates' peripheral blood mononuclear cells were found to be significantly less active than adults' in ADCC lysis of HIV-infected cells. This pattern of diminished ADCC cytotoxicity with intact NKC is the opposite of that seen in HIV-infected adults. Our findings suggest that therapies designed to enhance ADCC effector cell function in the neonate may help interrupt vertical transmission of HIV.

Adult↗
PubMed1992

Adenoid cystic carcinoma of the breast.

Adenoid cystic carcinoma of the breast is a rare neoplasm, with only 140 cases having been reported to date. Data on 123 of these cases are reviewed herein and another case is presented in detail. Several features distinguish this type of breast cancer from more typical histologic types and suggest that it may have a unique tumor behavior. The prognosis appears to be favorable and the incidence of axillary lymph node involvement is lower. Distant metastases are uncommon, but they tend to occur without prior lymph node involvement. This lack of prognostic significance for negative axillary lymph nodes underscores the need for other prognostic markers in this disease and suggests that axillary dissection can be eliminated in most cases. Similarities to typical breast cancer include the incidence of local recurrence and the lack of effect of surgical treatment on distant metastases and overall survival. These data suggest that breast-conserving treatment may be applicable to adenoid cystic carcinoma.

Breast Neoplasms↗
PubMed1992

Expressed emotion in depressed patients and their partners.

This study was designed to assess the expressed emotion (EE) status in the spouses of depressed patients and the patients themselves, to relate the EE status to the severity of depression as measured by the Beck Depression Inventory (BDI), and to compare the prevalence of high EE between the target and control group. Seventeen depressed patients and their spouses, and 20 control couples participated in the study. The Five-Minute Speech Sample was used to assess the EE status. High EE was significantly more common in spouses of depressed patients and the patients themselves than in controls. There was a significant relationship between the EE status of the patients and their spouses. High EE in the patient and in the spouse corresponded significantly with a high BDI score of the patient. These findings underline the importance that in EE research the patients' EE status as well as their present mental health state must also be taken into account.

Adult↗
PubMed1992

New aspects of neonatal herpes.

Herpes simplex virus (HSV) is a rare but increasingly prevalent agent of newborn infection. Primary or first episode genital infection in the mother constitutes the greatest risk of infection in the neonate. Transplacental, HSV-specific functional antibody appears to protect infants from severe disease and may be therapeutically exploitable. Prevention of serious sequelae in the infant depends on early diagnosis and treatment of HSV-infected infants.

Antiviral Agents↗
PubMed1991

The majority of CD4+8- thymocytes are functionally immature.

The thymus is the major site of T cell development and repertoire selection. During these processes, T cells segregate into two subsets that express either CD4 or CD8 accessory molecules, the phenotype of peripheral T cells. Analysis of CD4+8- thymocytes revealed that the majority of these cells express the heat-stable Ag (HSA) but not the nonclassical class I Ag, Qa-2. This HSA+, Qa-2- phenotype is similar to that of the less mature, CD4+8+ thymocytes. The remaining CD4+8- thymocytes possess the HSA-, Qa-2+ phenotype of peripheral T cells. To determine whether the Qa-2-, CD4+8- thymic subset is fully mature, we have analyzed the functional status of these CD4+8- subpopulations. The results indicate that only those thymocytes which express Qa-2 are fully responsive to anti-TCR stimulation in a manner analogous to peripheral T cells. The Qa-2- subset is nonresponsive to stimulation by anti-TCR antibodies that have been immobilized to plastic, even in the presence of lymphokines or syngeneic APC. This subset is, however, capable of proliferating to allogeneic cells or to anti-TCR on the surface of syngeneic APC, although not to the levels achieved by Qa-2+ thymocytes. Thus, the Qa-2- subset appears to require additional interactions which are not necessary for peripheral T cells or Qa-2+ thymocytes. Relevant to this issue, the Qa-2+ thymocyte subset does not appear until relatively late in development, and does not reach adult frequencies until several weeks after birth. These results would suggest that there is a progression from HSA+, Qa-2- to HSA-, Qa-2+ which parallels the maturation of functional responsiveness. These findings are important to understanding T cell selection since thymocytes with such a decreased responsiveness may have a differential capacity for tolerance induction. The results presented suggest that the bulk of CD4+8- thymocytes are not fully mature and that Qa-2 may serve as a marker for T cells with a more complete functional competence.

Animals↗
PubMed1991

Childhood melanoma.

In melanoma patients, the prognostic value of tumor depth, Clark's level, the presence of ulceration, and regional involvement have not been clearly documented in the pediatric population. This report correlates these factors in a population-based study of patients under the age of 20 years. Of the initial 35 melanoma patients registered in southern Alberta with the Alberta Cancer Board, 14 were found on review to have a diagnosis other than melanoma. In the remaining 21 cases the diagnosis of melanoma was confirmed. There was a suggestion that patients with deeper lesions had a worse prognosis, but this was statistically confirmed only using Clark's levels. The children were then compared with all melanoma patients diagnosed in southern Alberta over the same time period. There was no difference in tumor depth, Clark's level, ulceration, regional involvement, or survival between these two groups. The natural history in children appears to be similar to that of the adult population, contrary to previous reports suggesting a markedly worse prognosis.

Adolescent↗