Biomedical subjects

J Dunn

Publications and source records attributed to J Dunn.

At least 55 records · Page 3Linked to original sources

PubMed2000

Agenesis of the gallbladder.

Agenesis of the gallbladder is rare. Three groups have been identified: those with multiple fetal anomalies, asymptomatic cases, and symptomatic cases. Right upper quadrant pain is present in 90% of the cases, nausea and vomiting in 60%, and jaundice in 35%. Operative strategy is aimed at thorough exploration to locate an aberrant gallbladder. We treated a 72-year-old woman with right upper quadrant pain, nausea, and vomiting but no fever or jaundice. Physical examination revealed right upper quadrant tenderness without rebound. The white blood cell count was 10,300/mm3. Total bilirubin level was 1.6 mg/dL. Ultrasonography revealed one gallstone and an enlarged common bile duct. Laparoscopic cholecystectomy was converted to open technique after failure to locate the gallbladder. On intraoperative cholangiogram, no gallbladder was identified. A T-tube was placed.

Abdominal Pain↗

PubMed2000

Parents' and partners' life course and family experiences: links with parent-child relationships in different family settings.

Life course and current family factors associated with individual differences in parent-child relationships were investigated in a sample of 467 children from 192 families, including stepfather, single-parent, stepmother, and complex stepfamilies; informants were fathers, mothers, and children. Both positive and negative dimensions of father-child and mother-child relationships were linked to earlier life course experiences of parent and of partner, to current family factors, and to the quality of partner's relationship with the child. The pattern of associations between the adults' life course experiences meant that children were at risk for a "double dose" of less affectionate relationships in families in which parents had experienced early adversities. The significance of biological relatedness, family setting, and child partner relationships was highlighted.

Adolescent↗

PubMed2000

Nuclear factor kappaB activation in acute appendicitis: a molecular marker for extent of disease?

Nuclear factor-kappaB (NF-kappaB) has been demonstrated to regulate the transcription of target genes and stimulate inflammatory cytokine responses in a variety of inflammatory diseases. Preliminary studies have demonstrated that NF-kappaB is activated early in acute inflammation and sepsis and may serve as an indicator of clinical severity. The present study was designed to evaluate the degree of activation of NF-kappaB in patients with acute appendicitis and correlate activation with clinical extent of disease. Ten patients with acute appendicitis and five control patients (elective inguinal hernia repair) were evaluated by assaying NF-kappaB activity preoperatively and 12 to 18 hours postoperatively. Assaying of NF-kappaB was determined by binding activity for consensus probes in nuclear extracts from peripheral mixed white blood cells obtained by venous puncture. The bands of NF-kappaB activity from gel electrophoresis were quantified with a phosphor imager and reported as units of integrated intensity. The preoperative NF-kappaB activity was increased in all patients with appendicitis versus the controls [mean 151 (range 97-189) vs mean 50.3 (range 13.7-77); P < 0.0001]. The increased NF-kappaB activity also correlated with length of time of symptoms before operation. The patients who were symptomatic for less than 24 hours had an average NF-kappaB value of 103 (range 97-105) versus 171.4 (range 152-189) (P < 0.0001) in those who were symptomatic 24 or more hours. The NF-kappaB activity did not correlate with the white blood cell count. Postoperative NF-kappaB binding activity in the appendicitis patients dropped to minimal levels (mean 50.3), even lower than the control patients' baseline values (mean 55.6). Control patients demonstrated low baseline values preoperatively and a slight rise postoperatively [mean 50.3 (range 13.7-77) vs mean 100 (range 45-186)]. We conclude the following: (1) NF-kappaB binding activity is elevated in patients with acute appendicitis and correlates with symptoms longer than 24 hours. (2) This increased activity returns to baseline values within 18 hours after appendectomy. (3) Molecular indicators of inflammation may have a role in both staging surgical inflammatory conditions and predicting ultimate outcome.

Acute Disease↗

PubMed1999

Expression of doublecortin correlates with neuronal migration and pattern formation in diverse regions of the developing chick brain.

The development of functional layers in the brain involves spatially and temporally regulated gene expression. Through cDNA library screening, we have identified genes that are expressed in a neural-specific manner during brain development. Sequencing and expression data indicate that one of the clones, 18C15, is the chick homologue of doublecortin, a human X-linked gene found to be mutated in subcortical laminar heterotopia (double cortex syndrome) and lissencephaly. The 18C15 mRNA contains multiple motifs that are known to regulate mRNA stability in response to inductive signals, and these motifs are conserved between the chick and human sequences. Doublecortin is found to be expressed at peak levels during early development of the cerebellum and forebrain, and is expressed in other regions including the tectum, spinal cord, and dorsal root ganglia. This study demonstrates both spatial and temporal regulation of doublecortin expression in the chick, which is associated with early events in brain development, including neuronal migration.

3' Untranslated Regions↗

PubMed1999

Multiple target sites of allelic imbalance on chromosome 17 in Barrett's oesophageal cancer.

Twelve Barrett's adenocarcinomas have been analysed for the occurrence of allelic imbalance (LOH) on chromosome 17 using 41 microsatellite markers. This study provides evidence for 13 minimal regions of LOH, six on 17p and seven on 17q. Four of these centre in the vicinity of the known tumour suppressor genes (TSGs) TP53 (17p13.1), NFI (17q11.2), BRCA1 (17q21.1), and a putative TSG (17p13.3). The tumours all displayed relatively small regions of LOH (1-10 cM), and in several tumours extensive regions of LOH were detected. One tumour displayed only two very small regions of LOH; 17p11.2 and 17p13.1. The frequency of allelic imbalance has been calculated based on the LOH encompassing only one minimal region, and based on all the LOH observations. By both evaluations the highest LOH frequencies were found for regions II (p53), III (17p13.1 centromeric to p53), IV (17p12), V (17p11.2) and VII (NF1, 17q11.2). Our data supports the existence of multiple TSGs on chromosome 17 and challenges the view that p53 is the sole target of LOH on 17p in Barrett's adenocarcinoma.

Adenocarcinoma↗

PubMed1999

Relation of genetic polymorphisms of apolipoprotein E, angiotensin converting enzyme, apolipoprotein B-100, and glycoprotein IIIa and early-onset coronary heart disease.

OBJECTIVE: Apolipoprotein E (APOE) E4, apolipoprotein B-100 (APOB) Q3611 allele, the angiotensin converting enzyme (ACE) deletion (D) allele and glycoprotein IIIa (GP3A) P33 mutant allele are reported to predispose to early-onset coronary heart disease (CHD). These associations were not all confirmed in more recent studies. To determine the impact of these alleles on CHD, we examined the prevalence of these mutations in patients presenting with early-onset CHD and compared them to those manifesting CHD later in life. The delayed-onset was considered a sign of longevity and would serve as a comparative group to assess prevalence of the biochemical and genetic risk factors. METHODS: 300 patients with a history of myocardial infarction or angina pectoris and angiographically documented CHD were studied. Patients were divided into two groups: group 1 (G1 = 150 patients) presenting with these findings under the age of 50 years; while group 2 (G2 = 150 patients) were patients presenting for the first time over the age of 65 years. Prevalence of the alleles of APOE, APOB, ACE and GP3A was assessed by molecular analysis. An association of any of these genotypes with early onset CHD could lead to a higher prevalence in the younger age group. RESULTS AND CONCLUSIONS: None of the suspected alleles namely APOB Q3611 [G1: 10.7% vs. G2: 9.0%, p = 0.57], ACE D (G1: 52.0% vs. G2: 49.7%, p = 0.57), or the GP3A P33 (G1: 17.3% vs. G2: 15.7%; p = 0.58) showed any significant difference between the two groups. Subjects with APOE E4 were more frequent in the younger age group (G1: 18.3% vs. G2: 13.7%; p = 0.047), while APOE E2 was more frequent in G2 (G2: 10.0% vs. G1: 2.7%; p = 0.0002). Multivariate analysis showed an odds ratio of APOE E2 allele in G1 of 0.27 with a confidence interval of 0.10-0.73.

Adult↗

PubMed1999

Analysis of CD34 populations in mobilised peripheral blood stem cell harvests and in bone marrow by fluorescent in situ hybridisation for the bcr/abl gene fusion in patients with chronic granulocytic leukaemia.

For those patients ineligible for allogeneic bone marrow transplant and who are non-responsive to interferon, autotransplant with peripheral blood stem cells (PBSC) mobilised after intensive chemotherapy, may provide a novel approach to improve prognosis in patients with chronic granulocytic leukaemia. PBSC harvests are assessed for CD34-positive cell numbers, which serve as an indicator of engraftment potential, and are also analysed cytogenetically to ascertain tumour cell contamination. However, a more accurate assessment of PBSC harvest contamination requires investigation of the Philadelphia (Ph) status of the CD34pos population, in which the cells that provide long-term engraftment are contained. In this study, we have analysed these levels in mobilised PBSC and also in bone marrow (BM) harvests, taken several weeks prior to mobilising chemotherapy. Using fluorescent in situ hybridisation for the bcr/abl gene fusion, we have shown that the median number of Ph negative cells in CD34pos isolated populations was 14.95% in BM compared to 79.05% in PBSC harvests and that in all PBSC samples tested, Ph positivity in CD34pos populations was always detectable either by FISH or one round PCR methods. In paired assessments of both PBSC and BM harvests, higher levels of Ph negative CD34pos cells (> or = 14%) isolated from BM harvests, taken prior to intensive chemotherapy, correlated with higher levels of Ph negative CD34pos cells (> or = 78.5%) in PBSC harvests. These data may aid in the selection of patients for whom PBSC harvesting, after mobilisation, is more likely to achieve an autograft product containing predominantly Ph negative CD34pos cells and may exclude those patients for whom the risk, morbidity and expense of stem cell harvesting may have no apparent benefit over a chronic phase BM harvest.

Adult↗

PubMed1999

Transitions in the route of cocaine administration--characteristics, direction and associated variables.

AIMS: To examine transitions in the route of administration of cocaine and the variables associated with them. DESIGN: A cross-sectional study undertaken between January 1996 and October 1997. SETTING: Fifteen different services that offer treatment, counselling or assistance to drug users or HIV-positive patients in the State of São Paulo, Brazil. PARTICIPANTS: Two hundred and ninety-four current or ex-cocaine and crack cocaine users. MEASUREMENTS: A structured interview schedule was developed consisting of 246 questions covering socio-demographic details, drug history, cocaine transitions and HIV-risk behaviours. FINDINGS: Eighty-seven per cent of patients began using cocaine by snorting and 74% subsequently underwent a transition of route--68% towards smoking and 20% to injecting. Half of all transitions occurred in the first 3 years following initiation into cocaine use. Factors associated with transitions were: younger age at cocaine initiation, more frequent use at peak usage, initial use of cocaine by snorting or injecting, a lower level of scholastic attainment and experience with a wider range of drug classes. A cohort effect was apparent with younger cocaine users and those who had begun using after 1990 being more likely to undergo a transition to smoking crack and less likely to start injecting. CONCLUSIONS: Cocaine transitions are very common and are usually towards routes associated with a higher dependency potential and increased HIV-risk behaviour. Further research is needed to see if transitions can be prevented by early identification of potential cases.

Administration, Inhalation↗

PubMed1999

Pre-conception diabetes care in insulin-dependent diabetes mellitus.

Prospective studies of pre-conception diabetes care have confirmed its positive impact on the incidence of malformations by improving glycaemic control. Less information is available on the impact of pre-conception care on maternal and neonatal morbidity. This audit addresses its impact on timing and mode of delivery, incidence of macrosomia and rate of admission to neonatal unit care in addition to sociodemographic factors which may influence attendance at such a service. Attenders were more likely to be in a stable relationship and be non-smokers. They were more likely to book for antenatal care earlier and with a lower glycated haemoglobin. There were no early deliveries (i.e. < 30 weeks) or small for gestational age (SGA) babies in those who attended for pre-conception care and no neonatal deaths. Admission to NNU care was reduced by 50% in those who attended for pre-conception care. Although the rate of macrosomia was reduced, there was no impact on the Caesarian section rate. A pre-conception diabetes clinic may have a positive impact on neonatal morbidity.

Cesarean Section↗

PubMed1999

Psychostimulant prescriptions by psychiatrists higher than expected: a self-report survey.

OBJECTIVE: To survey Alberta psychiatrists on their prescribing of psychostimulants to adults. METHOD: A questionnaire was mailed to all 245 registered psychiatrists in Alberta. The respondents were requested to anonymously report, for the previous year, the number of adult patients to whom they prescribed pemoline, methylphenidate, amphetamines, or other psychostimulants for the treatment of adult attention-deficit hyperactivity disorder (ADHD), narcolepsy, unipolar depression, bipolar disorder, dementia, and other disorders. RESULTS: The response rate was 93.9%; 88.7% treated adults. Of these, 46.6% prescribed psychostimulants to 1238 patients. The greatest proportion of prescriptions of psychostimulants was for adult ADHD, depression, and narcolepsy. CONCLUSIONS: Psychostimulants are more widely prescribed by psychiatrists than indicated in earlier studies and in recommendations for treatment.

Adult↗

PubMed1999

Epidemiological methods for research with drug misusers: review of methods for studying prevalence and morbidity.

Epidemiological studies of drug misusers have until recently relied on two main forms of sampling: probability and convenience. The former has been used when the aim was simply to estimate the prevalence of the condition and the latter when in depth studies of the characteristics, profiles and behaviour of drug users were required, but each method has its limitations. Probability samples become impracticable when the prevalence of the condition is very low, less than 0.5% for example, or when the condition being studied is a clandestine activity such as illicit drug use. When stratified random samples are used, it may be difficult to obtain a truly representative sample, depending on the quality of the information used to develop the stratification strategy. The main limitation of studies using convenience samples is that the results cannot be generalised to the whole population of drug users due to selection bias and a lack of information concerning the sampling frame. New methods have been developed which aim to overcome some of these difficulties, for example, social network analysis, snowball sampling, capture-recapture techniques, privileged access interviewer method and contact tracing. All these methods have been applied to the study of drug misuse. The various methods are described and examples of their use given, drawn from both the Brazilian and international drug misuse literature.

Epidemiologic Methods↗

PubMed1999

Cocaine--profiles, drug histories, and patterns of use of patients from Brazil.

We studied profiles and drug histories of 294 cocaine users from 15 treatment services in São Paulo, Brazil during 1996-1997. Mean age of subjects was 27 years, and 90% were male. Over 50% had used five different substances apart from cocaine, usually tobacco, alcohol, cannabis, tranquilizers, and solvents. Mean age at first cocaine use was 18.9 years by which time 87% had snorted the drug. Thirty-two percent had injected cocaine, 82% had smoked crack, and 74% reported a full route transition. Sixty-three percent reported daily cocaine use. Median duration of cocaine use was 6.3 years. Acts of acquisitive crime were common, and 56% had been arrested. Our finding are discussed in terms of implications for prevention and treatment.

Adolescent↗

PubMed1999

Parental divorce and adjustment in adulthood: findings from a community sample. The ALSPAC Study Team. Avon Longitudinal Study of Pregnancy and Childhood.

The current study examines the link between the experience of divorce in childhood and several indices of adjustment in adulthood in a large community sample of women. Results replicated previous research on the long-term correlation between parental divorce and depression and divorce in adulthood. Results further suggested that parental divorce was associated with a wide range of early risk factors, life course patterns, and several indices of adult adjustment. Regression analyses indicated that the long-term correlation between parental divorce and depression in adulthood is explained by quality of parent-child and parental marital relations (in childhood), concurrent levels of stressful life events and social support, and cohabitation. The long-term association between parental divorce and experiencing a divorce in adulthood was partly mediated through quality of parent-child relations, teenage pregnancy, leaving home before 18 years, and educational attainment.

Adolescent↗

PubMed1999

Survey of neonatal hepatitis B vaccination in Leicestershire.

Some 121,390 live and still births were recorded in Leicestershire between June 1986 and May 1995. All mothers were offered antenatal screening for hepatitis B and 161 were positive for hepatitis B surface antigen. Examination of case notes from 113 mother and baby pairs identified 70 infants who fulfilled criteria for vaccination in place at the time, 47 of whom (67%) had received the three doses of hepatitis B vaccine then recommended for prevention of neonatal infection.

England↗

PubMed1999

Siblings, parents, and partners: family relationships within a longitudinal community study. ALSPAC study team. Avon Longitudinal Study of Pregnancy and Childhood.

Links between sibling relationships, mother-partner, and parent-child relationships were studied in a longitudinal community sample of 3681 sibling pairs. Individual differences in sibling relationship quality were related to mother-partner affection and hostility assessed 4 years earlier, to contemporary parent-child negativity, and to indices of social adversity. Evidence for both direct and indirect pathways (via parent-child relations) linking mother-partner and sibling relations were found. Comparisons of prediction for non-stepfamilies and stepfather families showed similarities in patterns of association, but also differences: In stepfather families, mother-partner hostility was unrelated to parent-child negativity and sibling relationship quality. Both positivity and negativity towards young siblings decreased with the age of older siblings, and older sisters were more positive than older brothers.

Adult↗

PubMed1999

Lack of effect of cimetidine on the pharmacokinetics of sustained-release bupropion.

The objective of this study was to assess whether cimetidine affects the pharmacokinetics of sustained-release (SR) bupropion hydrochloride and the active metabolite, hydroxybupropion. This randomized, open-label, two-period crossover study was conducted in 24 healthy volunteers 18 to 45 years of age. ANOVA showed that administration of two 150 mg bupropion SR tablets with one 800 mg cimetidine tablet following an overnight fast did not change values for AUC infinity, Cmax, tmax, t1/2, and CL/F (CL/F calculated for bupropion only) for either bupropion or hydroxybupropion as compared with two 150 mg bupropion SR tablets alone. In this study, it appears that there is no effect of cimetidine on the pharmacokinetics of bupropion SR.

Adolescent↗

PubMed1999

Health care coverage of high school athletics in South Carolina: does school size make a difference?

Despite an apparently high injury rate, medical coverage available to these high school athletes is often not immediately present during practice and games. The purpose of the present study was to examine the current conditions of health care coverage and delivery to the football program and associated athletic departments in the public and private high schools in South Carolina. Additionally, the relationship between student enrollment and medical coverage was examined. A survey, based upon previously utilized instruments, was sent to the athletic directors at the public and private high schools with interscholastic football programs in South Carolina. The survey included questions pertaining to the medical coverage, including personnel, equipment, and record systems, for football practices and games. Based upon the results of the survey, a majority of high schools in South Carolina appear to have adequate sports medicine coverage and compare favorably with the results of similar data from other states. The medical coverage does significantly vary depending upon the enrollment size of the high school. In spite of this finding, the health care provided high school athletes is often inconsistent and training and equipment required for basic first aid is often absent.

Adolescent↗

PubMed1999

Radiation-related arterial disease.

Arterial occlusive disease has been recognized in association with radiation arteriopathy and, rarely, with spontaneous arterial disruption. This association results from the greater role of radiation therapy in the current management of malignant diseases coupled with longer patient survival and the lengthy latency period between radiation and clinical manifestations of radiation arteriopathy. Experience with six patients having radiation-associated arterial disease was retrospectively reviewed. There were four men and two women, with a mean age of 51 years (range, 36-74). Arteries exposed to radiation include two carotids, three subclavians, one coronary, and one femoral. The time from radiation therapy until clinical arterial disease was a mean of 14.3 years (range, 4-30). Operative repairs with polytetrafluoroethylene and saphenous vein bypass grafts were performed in four patients, stent placement in one patient, and one patient had spontaneous carotid disruption that ultimately was treated with ligation. In conclusion, elective bypass can be performed safely and successfully for arterial occlusive disease in a previously irradiated artery. In contrast, life-threatening arterial disruption secondary to radiation arteriopathy usually requires concomitant exposure to a source of bacterial contamination, and ligation may be the best choice to prevent recurrent hemorrhage.

Adult↗