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PubMedDate not supplied

[Implantation of a pacemaker through persistent left superior vena cava].

Persistent left superior vena is a relatively rare congenital variant. It is, however, the most common variation of the thoracic venous system. Prevalence is estimated in about 0.6 to 1.0% during pacemaker placement. This finding, often incidental, can difficult the lead progression through the left jugular or subclavian routes. This report describes a case of successful pacemaker implantation through a persistent left superior vena. Technical difficulties were overcome using the pacemaker electrode as unipolar lead. Endocavitary ECG recording helped us to guide the lead through the tortuous anatomy. A stable lead position was finally achieved by means of the active fixation system of the pacemaker electrode.

Aged↗

PubMed2005

[Arbovirus survey in some regions in Heilongjiang province].

BACKGROUND: Mosquitoes were collected in Heilongjiang province in 2002, four virus strains were isolated by inoculation of homogenates onto BHK cell lines. The viruses were identified. Multiple alignment and phylogenetic analysis were carried out by Clustal X (1.8) program.Amino acid (AA) analysis was carried out by GENEDOS (3.2). RESULTS: Biological characters of four newly isolated strains were examined and it was found that all of them could produce cytopathogenic effect (CPE) in BHK cells, killing sucking mice. Serological tests showed that all of these stains reacted positively to JEV antibodies. PrM and E gene regions were amplified and sequenced. Phylogenic analysis showed that all the newly isolated JEV strains belong to genotype III. Using the vaccine strains (SA14-14-2) as control, analysis of the E gene of the new strains and two JEV strains (47, Ha-3) isolated previously from Heilongjiang province showed that these new strains' nucleotide sequence had a homology of up to 99.9% and the amino acid sequence homology up to 99.8%, respectively. Compared with the standard JE vaccine strain SA-14-14-2 and the four new strains, the nucleotide sequence homology was 97.3% and amino acid sequence homology was between 96.8% and 97.0%, respectively. Compared with vaccine strain, there were seven common variations in all the four newly isolated strains. CONCLUSION: Four JE virus strains were isolated in Heilongjiang province. As compared to the vaccine strain, six variations were found in the newly isolated strains at the eight sites relevant to the virulence of the virus.

Animals↗

PubMed1991

[An object analytical procedure for determining the area of the thyroid gland parenchyma accumulating nuclides in the scintigram].

An algorithm for object isolation was developed to determine the area of the thyroid in scintigraphic images, and its volume calculated therefrom so that operator-induced variations, common if the usual manual technique is used, could be avoided. The object isolation is performed for every possible threshold value. The resulting object isolation curves give a reliable and reproducible thyroid area. The method may be used routinely except in cases of blocked thyroid uptake or of multiple autonomous adenomas.

Algorithms↗

PubMed1985

Congenital hemifacial hyperplasia: an embryologic hypothesis and case report.

Congenital hyperplasia is a developmental disorder characterized by marked unilateral asymmetry. The structural disproportions from one side to the other far exceed variations commonly seen in the normal population. Classically, as first described in 1836, the overgrowth of tissue is restricted to one-half of the body, including the extremities. In other cases the hyperplastic enlargement involves segmental areas of the body, such as the hemifacial skeleton and an extremity. A case report is presented, and the clinical characteristics of 192 cases of congenital hyperplasia in the literature are briefly reviewed. Use of the word hyperplasia to describe the condition (rather than hypertrophy) is encouraged. The authors propose a new embryologic hypothesis: asymmetrical development of the neural fold and hyperplasia of the neural crest cells are said to form the basis for the disorder. The rewards, risks, and limitations of reconstructive surgery over a 10-year period are discussed.

Child, Preschool↗

PubMed1984

The lateral chest radiograph in the assessment of nonpulmonary health and disease.

The lateral chest radiograph contains a wealth of data on the status of the thoracic cage, pleura, heart, pericardium, bronchi, and upper abdomen. The appearances of slightly oblique projections deviating from the "true" lateral projection are reviewed. Careful attention to these common variations of projection is advocated.

Adult↗

PubMed1982

[A new technical procedure for middle and lower lobe lobectomy].

Among combined pulmonary resections, one of the most difficult operations is right middle and lower lobe lobectomy because of the very intricate anatomical relations between the three pulmonary lobes. Technical difficulties during the first-stage approach to the pulmonary artery in the fissure are compounded by the presence of pathological processes (neoplasm, suppuration, etc.) which provoke adhesions between the pulmonary artery and the bronchus, with inevitable major risks. A new technique for middle and lower lobe lobectomy which avoids the frequent accidents during this operation is described. The first stage involves ligature and section of the inferior root of the superior pulmonary vein and liberation of the horizontal fissure. Opening of the horizontal fissure exposes the superior fissural vein, which is then displaced towards the upper lobe. This allows access to the pulmonary artery in the fissure, together with its branches to the lower and middle lobes, and the fissural arteries to the upper lobe. This procedure enables simple dissection and ligature of the pulmonary artery, as at this level it is not adherent to the intermediary part of the bronchus. The triangular ligament, inferior pulmonary vein, and intermediary bronchus are then ligatured and sectioned. The advantages of this method consist in the simplification of the dissection, ligature, and section of the pulmonary artery in the fissure, and the need to apply only one ligature if there are no anatomical variations (common dorsal fissural and inferior apical artery, or common ventral fissural and middle lobe artery).

Humans↗

PubMed1981

Integrating ethnographic research with nutrition studies.

A major methodological problem is dietary intake research is the specification of an adequate sampling design. Ethnographic research provides the investigator with essential data for more effective research design by establishing sources of temporal variation in food intake and by identifying significant consumption settings and main sociocultural characteristics affecting intracommunity differences in foot intake. A checklist of sources of temporal variation commonly found in various societies is presented as a guide for ethnographic work. Other uses of ethnography to improve dietary intake methodology are the identification of culturally and socially sensitive aspects of food use and the provision of background information for the interpretation of research results.

Anthropology, Cultural↗

PubMed1981

Human apolipoprotein E isoprotein subclasses are genetically determined.

In a recent communication, we showed that human very low density lipoprotein (VLDL) apolipoprotein E (Apo E) from different individuals appears upon two-dimensional gel electrophoretic analysis in either one of two complex patterns. These have been designated class alpha and class beta. Mixing of VLDL from different subjects revealed that not all alpha or beta apo E patterns were the same. In this manner, we identified three subclasses of class alpha (alpha II, alpha III, and alpha IV) and three subclasses of class beta (beta II, beta III, and beta IV). We report here the results of family studies that reveal that the subclasses (alpha II, alph III, and alpha IV and beta II, beta III, and beta IV) of apo E are determined at a single genetic locus with three common alleles, epsilon II, epsilon III, and epsilon IV. The class beta phenotypes (beta II, beta III, and beta IV) represent homozygosity for two identical apo E alleles (epsilon). In contrast, class alpha phenotypes (alpha II, alpha III, and alpha IV) represent heterozygosity for two different apo E alleles. The apo E subclasses and their corresponding genotypes are as follows: beta II = epsilon II/epsilon II; beta III = epsilon III; beta IV = epsilon IV/epsilon IV; alpha II = epsilon II/epsilon III; alpha III = epsilon III/epsilon IV; and alpha IV = epsilon II/epsilon IV. To estimate the frequencies of the apo E alleles in the general population, apo E subclasses were then investigated in 61 unrelated volunteers and the results were: beta II = 1 (2%), beta III = 30 (49%), alpha II = 9 (15%, alpha III = 13 (31%), and alpha IV = 2 (3%). Utilizing the frequencies of these phenotypes, the gene frequencies were calculated to be epsilon II = 11%, epsilon III = 72%, and epsilon IV = 17%. In addition, apo E subclasses were studied in a clinic for individuals with plasma lipid disorders and the apo E subclass beta IV was found to be associated with type III hyperlipoproteinemia. There was no association of any apo E subclass with type II, type IV, or type VI hyperlipoproteinemia or plasma HDL cholesterol levels. This study explains the genetic basis for the common variation in a human plasma protein, apo E. Since the apo E subclass beta IV is associated with type III hyperlipoproteinemia, a disease characterized by xanthomatosis and premature atherosclerosis, understanding the genetic basis of the apo E subclasses should provide insight into the genetics of type III hyperlipoproteinemia.

Alleles↗

PubMed1994

The characteristics of the menstrual cycle in Nigerian schoolgirls and the implications for school health programmes.

The present study examines the characteristics of menstrual cycle among 361 Nigerian postmenarcheal schoolgirls derived from seven public secondary schools. Survey questions covered preparation for menstruation, duration of flow, cycle length, regularity, premenstrual syndrome and dysmenorrhea. For the study subjects the mean age (years) at the time of interview, at menarche, and completed since menarche are 16.5 +/- 3.3, 13.7 +/- 2.6 and 2.9 +/- 1.2 respectively. Premenstrual counselling was reported in 84.2%; and 48.6% was provided by parents and guardians, and 23.7% by school teachers. The findings indicate that menstrual flow < or = 2 days, and cycle length < or = 20 days are common; occurring in 20-30% of schoolgirls. Abnormal patterns such as cycle length > or = 38 days, flow duration > or = 8 days and heavy menstruation occurred in less than 5% of study subjects. Irregular menstrual cycles were recorded in 13%, and severe dysmenorrhea in 17.2%. Severe premenstrual syndrome occurred in about 20% of schoolgirls, with symptom-complex mainly of behavioural change, arousal and impaired concentration. The need for a multi-disciplinary school health counselling program that would provide relevant information on menstrual pattern and its common variation, identify abnormal patterns for early referral, provide psychological support and drug relief of distressing menstrual symptoms, and provide information on other contemporary adolescent problems is discussed.

Adolescent↗

PubMed1996

Asthma management at Christchurch Hospital: compliance with guidelines.

AIM: To audit compliance with guidelines for the assessment and management of adult patients admitted to Christchurch Hospital with acute asthma. METHODS: An asthma admission form and management guidelines, based on international consensus statements, were designed for use by resident staff at Christchurch Hospital. Compliance with these guidelines was audited during the winter of 1994 by means of retrospective case record review. RESULTS: One hundred and forty three admissions were screened. The form was used in 99 patients (69%), of which 97 had records available for audit. Sixty two patients were admitted under general medical services and 35 under respiratory specialist services. The median age was 34 years (range 14-84) and 77% were female. The history including interval status was adequately documented in over 95% of cases. Peak flow rate was recorded on admission in 93 patients (96%) and spirometry in 62 (64%). During the acute phase of treatment 528 items were prescribed, of which 382 (72%) were appropriate according to the guidelines. The major area (55%) of nonguideline prescribing was the use of nebulised ipratropium in addition to salbutamol for mild or moderate asthma. Written evidence of asthma education was present in 42 (43%). In 34 patients (35%) there was specific reference to the introduction of an asthma action plan. Of the 33 smokers only 17 appeared to have been given smoking cessation advice. Discharge prescribing complied with the guidelines in 71%. The most common variation from the guidelines for discharge therapy related to the manner of prednisone dose reduction. The readmission rate at 1 month was 11%. CONCLUSIONS: The introduction of an asthma admission form enhanced the quality of clinical data gathering by junior staff. Compliance with management guidelines was adequate. Specific sections pertaining to the use of chest radiographs, arterial blood gases and the prescribing of ipratropium and prednisone will be reviewed in updated guidelines.

Adolescent↗

PubMed1998

Reconstruction of replaced right hepatic artery, to implant a single-catheter port for intra-arterial hepatic chemotherapy.

Intra-arterial hepatic chemotherapy using an implantable subcutaneous port with a catheter inserted into the gastroduodenal artery is an acceptable treatment for patients with isolated, nonresectable liver metastases from colorectal cancer. Because of the common variations of hepatic arterial anatomy occurring in about one-half of the patients, this technique will result in complete perfusion of both hepatic lobes only in those with "classical" arterial anatomy (Michels type I). Many techniques have been described in these situations, usually using a dual-catheter port with the attendant risk of hepatic misperfusion and arterial thrombosis. We herein describe an alternative technique applicable to patients with a right hepatic artery arising from the superior mesenteric artery. In this technique the right hepatic artery is anastomosed end-to-end with the gastroduodenal artery, followed by implantation of a single-catheter port that is inserted into the splenic artery.

Adult↗

PubMed1998

Association study of structural mutations of the tyrosine hydroxylase gene with schizophrenia and Parkinson's disease.

Tyrosine hydroxylase (TH) gene is the rate-limiting enzyme in the synthesis of catecholamines. Functional polymorphisms of the TH gene may be involved in the pathogenesis of neuropsychiatric diseases such as schizophrenia, affective disorders, and Parkinsonism. This study examined a possible association of two polymorphisms, both of which result in an amino acid change of the TH protein, with schizophrenia and Parkinson's disease (PD). The Val81Met polymorphism is a common variation, although its effect on the enzyme expression is unclear. Leu205Pro polymorphism is a rare mutation that is reported to cause Parkinsonism in infancy for individuals who are homozygous for the mutated type. We genotyped a Japanese sample of 194 schizophrenics, 99 patients with PD, and 161 controls for the Val81Met polymorphism by using mis-match PCR and digestion by the restriction enzyme BalI. There was no significant allelic or genotypic association of the Val81Met polymorphism with schizophrenia or PD. The Leu205Pro polymorphism was examined by using PCR and digestion by AluI; however, there was no individual who carried the mutated type of Pro205 among 50 schizophrenics or 50 patients with PD. Thus we obtained no evidence for the involvement of the two structural mutations of the TH gene in the pathogenesis of schizophrenia or PD.

Alleles↗

PubMed2005

Inferences on the common coefficient of variation.

The coefficient of variation is often used as a measure of precision and reproducibility of data in medical and biological science. This paper considers the problem of making inference about the common population coefficient of variation when it is a priori suspected that several independent samples are from populations with a common coefficient of variation. The procedures for confidence interval estimation and hypothesis testing are developed based on the concepts of generalized variables. The coverage properties of the proposed confidence intervals and type-I errors of the proposed tests are evaluated by simulation. The proposed methods are illustrated by a real life example.

Blood↗

PubMed2005

Mitochondrial DNA variation of the common hippopotamus: evidence for a recent population expansion.

Mitochondrial DNA control region sequence variation was obtained and the population history of the common hippopotamus was inferred from 109 individuals from 13 localities covering six populations in sub-Saharan Africa. In all, 100 haplotypes were defined, of which 98 were locality specific. A relatively low overall nucleotide diversity was observed (pi = 1.9%), as compared to other large mammals so far studied from the same region. Within populations, nucleotide diversity varied from 1.52% in Zambia to 1.92% in Queen Elizabeth and Masai Mara. Overall, low but significant genetic differentiation was observed in the total data set (F(ST) = 0.138; P = 0.001), and at the population level, patterns of differentiation support previously suggested hippopotamus subspecies designations (F(CT) = 0.103; P = 0.015). Evidence that the common hippopotamus recently expanded were revealed by: (i) lack of clear geographical structure among haplotypes, (ii) mismatch distributions of pairwise differences (r = 0.0053; P = 0.012) and site-frequency spectra, (iii) Fu's neutrality statistics (F(S) = -155.409; P < 0.00001) and (iv) Fu and Li's statistical tests (D* = -3.191; P < 0.01, F* = -2.668; P = 0.01). Mismatch distributions, site-frequency spectra and neutrality statistics performed at subspecies level also supported expansion of Hippopotamus amphibius across Africa. We interpret observed common hippopotamus population history in terms of Pleistocene drainage overflow and suggest recognising the three subspecies that were sampled in this study as separate management units in future conservation planning.

Africa South of the Sahara↗

PubMed2004

Genetic variation in coding regions between and within commonly used inbred rat strains.

Single nucleotide polymorphisms (SNPs) are the most common genetic variation in mammalian populations. Their significance is illustrated by their potential contribution to common disease but also by their potential for use in genetic association and mapping experiments. We have examined the genetic variation between commonly used inbred rat strains by using an efficient SNP discovery and typing assay based on enzyme-based (CEL I) heteroduplex cleavage. Screening of a panel of 96 different rat (sub-)strains for 100 genomic loci in 55 genes, whose human homologs are implicated in clinically relevant diseases like neurological disorder, cancer, schizophrenia, and obesity, resulted in the identification of 103 novel polymorphisms. As all strains are simultaneously genotyped in this setup, this allowed us to make an estimate of the genetic variation between and within commonly used rat inbred strains. Interestingly, we observed substantial genetic variation between colonies of the same inbred strain, maintained at different locations. Furthermore, we identified 17 non-synonymous SNPs that may have an effect on protein function and contribute to phenotypic differences between different laboratory strains.

Animals↗

PubMed1998

Variation profiles of common surgical procedures.

BACKGROUND: Rates of many surgical procedures vary widely across both large and small geographic regions. Although variation in health care use has long been described, few studies have systematically compared variation profiles across surgical procedures. The goal of this study was to examine current patterns of regional variation in the rates of common surgical procedures. METHODS: The study population consisted of patients enrolled in Medicare in 1995, excluding those enrolled in risk-bearing health maintenance organizations. Patients ranged in age from 65 to 99 years. Using data from hospital discharge abstracts, we calculated rates of 11 common inpatient procedures for each of 306 US hospital referral regions (HRRs). To assess the relative variability of each procedure, we determined the number of low and high outlier regions (HRRs with rates < 50% or > 150% the national average) and the ratio of highest to lowest HRR rates. RESULTS: Procedures differed markedly in their variability. Rates of hip fracture repair, resection for colorectal cancer, and cholecystectomy varied only 1.9- to 2.9-fold across HRRs (0, 0, and 4 outlier regions, respectively). Coronary artery bypass grafting, transurethral prostatectomy, mastectomy, and total hip replacement had intermediate variation profiles, varying 3.5- to 4.7-fold across regions (8, 10, 16, and 17 outlier regions, respectively). Lower extremity revascularization, carotid endarterectomy, back surgery, and radical prostatectomy had the highest variation profiles, varying 6.5- to 10.1-fold across HRRs (25, 32, 39, and 56 outlier regions, respectively). CONCLUSIONS: Although the use of many surgical procedures varies widely across geographic areas, rates of "discretionary" procedures are most variable. To avoid potential overuse or underuse, efforts to increase consensus in clinical decision making should focus on these high variation procedures.

Aged↗

PubMed2005

Transcriptome analysis of human hepatic and pancreatic stellate cells: organ-specific variations of a common transcriptional phenotype.

Pancreatic stellate cells (PSCs) are thought to be the primary source of the extensive fibrotic reaction characteristic of pancreatic cancer and chronic pancreatitis in humans. PSCs share many morphological and functional characteristics with hepatic stellate cells (HSCs), whose central role in liver fibrosis is well established. However, it has remained unclear if hepatic and pancreatic stellate cells are derived from a common cell lineage and if they are completely similar or if they possess organ-specific features. We have analysed the transcriptomes of HSCs, PSCs and skin fibroblasts to assess how the transcriptional phenotype of stellate cells differs from that of a typical fibroblast lineage cell and if there is evidence for a common stellate cell precursor. To this end, we have performed expression profiling of primary cultures of human HSCs, PSCs and skin fibroblasts using 23,000-feature 'whole genome' oligonucleotide micro-arrays. Expression data were verified using real-time PCR. The expression profiles of HSCs and PSCs displayed a great extent of similarity, clearly separating them from the fibroblasts. Predominantly extracellular and cell surface genes, but also signalling molecules, transcription factors and novel neural markers, were concordantly expressed in both stellate cell types. Despite this high degree of similarity, distinct differences in expression patterns were observed between HSCs and PSCs, reflecting organ-specific variations of the common stellate cell-specific phenotype.

Cell Lineage↗

PubMed2005

Microbial reduction of selenate and nitrate: common themes and variations.

A number of biochemically distinct systems have been characterized for the microbial reduction of the oxyanions, selenate (SeO(4)(2-)) and nitrate (NO(3)(-)). Two classes of molybdenum-dependent nitrate reductase catalyse the respiratory-linked reduction of nitrate (NO(3)(-)) to nitrite (NO(2)(-)). The main respiratory nitrate reductase (NAR) is membrane-anchored, with its active site facing the cytoplasmic compartment. The other enzyme (NAP) is water-soluble and located in the periplasm. In recent years, our understanding of each of these enzyme systems has increased significantly. The crystal structures of both NAR and NAP have now been solved and they provide new insight into the structure, function and evolution of these respiratory complexes. In contrast, our understanding of microbial selenate (SeO(4)(2-)) reduction and respiration is at an early stage; however, similarities to the nitrate reductase systems are emerging. This review will consider some of the common themes and variations between the different classes of nitrate and selenate reductases.

Amino Acid Sequence↗