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Biomedical subjects

A Lee

Publications and source records attributed to A Lee.

At least 361 records · Page 20Linked to original sources
PubMed1997

Risk of unanticipated intraoperative events in patients assessed at a preanaesthetic clinic.

PURPOSE: To determine the risk of unanticipated intraoperative events (UIE) in patients assessed at a preanaesthetic clinic compared with those not assessed at the clinic. METHODS: Preoperative and intraoperative data were collected on 6130 elective surgical patients by procedural anaesthetists over a 12-month-period at an Australian tertiary referral hospital. The procedural anaesthetists rated the level of preparation and identified predefined unanticipated intraoperative events. A logistic regression model was used to identify significant risk factors of UIE and was further validated on another sample of 482 patients (one month) by a goodness-of-fit test. RESULTS: Of the 6130 elective surgical patients, 2000 (33%) had been assessed at the preanaesthetic clinic. There was a greater proportion of ASA II to IV patients seen at the clinic than patients not assessed at the clinic (chi 2(3) = 689.92, P < 0.001). Nonclinic patients were more likely to be inadequately prepared than clinic patients (RRunadjusted = 1.61, 95% CI: 1.25 to 2.04, P < 0.001). The overall incidence of intraoperative events was 4.14% (95% CI: 3.64% to 4.64%). Despite adjusting for the preparation level, type of anaesthesia, admission category, ASA physical status and duration of anaesthesia, clinic patients were 1.94 (95% CI: 1.42 to 2.64) times more likely to experience an UIE than nonclinic patients (P < 0.001). CONCLUSION: Although clinic patients were more often optimally prepared, their adjusted risk of UIE was higher than nonclinic patients. The procedural anaesthetist needs to be vigilant with these high risk patients, even if they have been assessed at a preanaesthetic clinic.

Adult↗
PubMed1997

Endometrial volume change during spontaneous menstrual cycles: volumetry by transvaginal three-dimensional ultrasound.

OBJECTIVE: At present, only limited data are available on endometrial volume during the menstrual cycle. Most of these studies deal with animal models and use magnetic resonance imaging for volume measuring. The application of three-dimensional ultrasound in endometrial volume estimation is the subject of this study. SETTING: Patients visiting the outpatient unit of the division of endocrinology and reproductive medicine of a university hospital. PATIENT(S): Twenty patients with a history of a normal menstrual cycle were selected. INTERVENTION(S): Ultrasound examinations were performed during a single menstrual cycle in addition to routine laboratory tests. MAIN OUTCOME MEASURE(S): Uterus-endometrial volume ratio. RESULT(S): Data from 18 patients could be evaluated. In 81 examinations the endometrium volume could be determined. Mean endometrial volume measured by three-dimensional ultrasound was 1.23 cm3. Mean uterus volume was 48.93 cm3. The change of the uterus-endometrial volume ratio showed a good correlation with the day of menstrual cycle. Quadratic regression analysis of volume and cycle length was R2 = 0.432. CONCLUSION(S): Three-dimensional ultrasound allows assessment of volume data of the female internal genitalia. In this study changes of the endometrial volume in menstrual cycles were measured. Additional studies are required to give information on the clinical impact of this new technique of endometrial volume estimation.

Endometrium↗
PubMed1997

Vascular endothelial growth factor levels in serum and follicular fluid of patients undergoing in vitro fertilization.

OBJECTIVE: To define the relationship between serum and follicular fluid (FF) levels of vascular endothelial growth factor (VEGF), E2, and P in patients undergoing IVF; to quantify the effects of hCG on serum levels of VEGF during early pregnancy, and to report serial measurements of serum and ascites fluid levels of VEGF in a patient with severe ovarian hyperstimulation syndrome (OHSS). DESIGN: Prospective observational study. SETTING: University IVF program. PATIENTS(S): Women undergoing conventional IVF, receiving donated oocytes or spontaneously conceiving. One patient hospitalized with severe OHSS. MAIN OUTCOME MEASURE(S): Concentrations of VEGF, E2, and P in serum, FF, or peritoneal fluid. RESULT(S): At the time of egg retrieval, FF VEGF concentrations were positively correlated with serum and FF P concentrations and with patient age. At 11 to 14 days after ET, pregnant recipients of autologous fresh embryos had higher serum VEGF levels than both nonpregnant recipients of autologous fresh embryos and pregnant recipients of donor eggs. Elevated serum VEGF levels in a patient with severe OHSS coincided with the clinical onset and recurrence of symptoms. CONCLUSION(S): In patients undergoing IVF, FF VEGF levels at the time of egg retrieval correlated with the degree of follicular luteinization. There is a significant ovarian contribution to circulating VEGF levels during early gestation. Elevated serum VEGF levels may be a factor in the etiology of OHSS symptoms.

Adult↗
PubMed1997

A standardized mouse model of Helicobacter pylori infection: introducing the Sydney strain.

BACKGROUND & AIMS: Currently available Helicobacter pylori models show variable and, in some instances, poor colonization. There is a need for a strain with high colonizing ability to act as a standard for animal studies. METHODS: After screening a range of fresh clinical isolates and long-term adaptation in mice, a strain of H. pylon has been isolated with a very good colonizing ability. RESULTS: This strain, named the Sydney strain of H. pylori (strain SS1), is cagA and vacA positive. High levels of colonization (10(6)-10(7) colony-forming units/g tissue) were achieved consistently in C57BL/6 mice. Colonization levels varied depending on the mouse strain used with BALB/c, DBA/2, and C3H/He, all being colonized but in lower numbers. In all strains of mice, bacteria were clearly visible at the junctional zone between the antrum and the body. The phenotype was stable with colonizing ability remaining after 20 subcultures in vitro. The bacterium attached firmly to gastric epithelium. During 8 months, a chronic active gastritis slowly developed, progressing to severe atrophy in both C57BL/6 and BALB/c mice. CONCLUSIONS: The Sydney strain of H. pylori is available to all and will provide a standardized mouse model for vaccine development, compound screening, and studies in pathogenesis.

Animals↗
PubMed1997

Comparison of the effects of oral versus intravenous methylprednisolone regimens on peripheral blood T lymphocyte adhesion molecule expression, T cell subsets distribution and TNF alpha concentrations in multiple sclerosis.

We investigated in multiple sclerosis the difference between two commonly used oral and intravenous steroid regimens on the level of adhesion molecule expression on blood T lymphocytes, the distribution of circulating T cell subsets, and the concentration of serum tumour necrosis factor alpha. Venous blood samples were collected from a cohort of 22 patients with acute relapses who were participating in a randomised trial comparing intravenous methylprednisolone 1000 mg daily for 3 days with oral methylprednisolone 48 mg daily for one week, 24 mg daily for one week, and finally 12 mg daily for one week. There was a similar significant reduction of T cell LFA-1 surface expression and serum TNF alpha concentrations after 4 days of treatment with each regimen. There was no change in other lymphocyte adhesion molecules expression (ICAM-1, LFA-3 or CD2) at day 4, although LFA-3 and CD2 expression was moderately decreased at day 28 and day 90 respectively; nor was there any change in the distribution of lymphocyte subsets (CD4, CD8, and CD45RA, CD45RO), although a small decrease in CD45RO circulatory T cells was noted at day 28. This study suggests that some of the beneficial effects of glucocorticosteroids may be related to the inhibition of lymphocyte adhesion as well as the modulation of proinflammatory cytokines.

Administration, Oral↗
PubMed1997

Elevation of intracranial pressure following transjugular intrahepatic portosystemic stent-shunt for variceal haemorrhage.

Increased intracranial pressure and cerebral oedema in patients with chronic liver disease is rare and is more typical of acute liver failure. Transjugular intrahepatic portosystemic stent-shunt is being increasingly used in the management of uncontrolled variceal haemorrhage in patients with cirrhosis. In our institution, a total of 160 patients has undergone transjugular intrahepatic porto-systemic stent-shunt for variceal haemorrhage; 56 of these procedures were emergencies for uncontrolled variceal haemorrhage. Four of these 56 patients developed features of acute liver failure, with marked deterioration in liver function tests and elevated intracranial pressure. This unusual but important complication of transjugular intrahepatic portosystemic stent-shunt has not been reported in the literature previously, and may have important consequences both for clinical practice and in the provision of further clues to understanding the pathogenesis of increased intracranial pressure in patients with liver diseases.

Adult↗
PubMed1997

Confirmation of linkage of oculopharyngeal muscular dystrophy to chromosome 14q11.2-q13 in American families suggests the existence of a second causal mutation.

Oculopharyngeal muscular dystrophy (OPMD) is a late-onset, autosomal dominant disorder characterized by progressive ptosis, dysphagia, and extremity weakness. Linkage of OPMD to 14q11.2-q13 has been reported in a series of French-Canadian families. Tightly linked markers have been defined and haplotype analysis in these data show a single segregating disease chromosome throughout the OPMD French-Canadian families. We have ascertained and sampled five multigenerational outbred American OPMD families. Four of the five families have known French-Canadian ancestry while the fifth is of English/Scottish origin. Linkage analysis was performed using standard likelihood methods. A peak multipoint lod score of 6.30 was obtained for the marker MYH7.1 in the OPMD families. The English/ Scottish family exhibited a different chromosomal haplotype for the OPMD alleles than the families of French-Canadian origin. These data suggest this family may represent a second, possibly independent mutation in this disorder. Linkage was confirmed to chromosome 14q11.2-q13 with no evidence of genetic heterogeneity.

Adult↗
PubMed1997

Characterization of the three-compartment gel-entrapment porcine hepatocyte bioartificial liver.

A hybrid bioartificial liver device supporting a large mass of cells expressing differentiated hepatocyte metabolic capabilities is necessary for the successful treatment of fulminant hepatic failure. The three-compartment gel-entrapment porcine hepatocyte bioartificial liver was designed to provide "bridge" support to transplantation or until native liver recovery is achieved for patients with acute liver failure. The device is an automated mammalian cell culture system supporting 6-7 x 10(9) porcine hepatocytes entrapped in a collagen matrix and inoculated into the capillary lumen spaces of two 100 kDa molecular mass cut-off hollow fiber bioreactors. Gel contraction recreates a small lumen space within the hollow fiber which allows for the delivery of a nutrient medium. This configuration supported hepatocyte viability and differentiated phenotype as measured by albumin synthesis, ureagenesis, oxygen consumption, and vital dye staining during both cell culture and ex vivo application. The hollow fiber membrane was also shown to isolate the cells from xenogenic immunoglobulin attack. The gel-entrapment bioartificial liver maintained a large mass of functional hepatocytes by providing a three-dimensional cell culture matrix, by delivering basal nutrients through lumen media perfusion, and by preventing rejection of the xenocytes. These features make this device a favorable candidate for the treatment of clinical fulminant hepatic failure.

Animals↗
PubMed1997

Cisapride use during human pregnancy: a prospective, controlled multicenter study.

The objective of this prospective multicenter study was to determine whether cisapride is associated with increased risk of malformations, spontaneous abortions, or decreased birthweight when used during pregnancy. Cases were paired for age, smoking, and alcohol consumption with controls exposed to nonteratogens, as well as with disease-paired controls. One hundred and twenty-nine pregnant women were exposed to cisapride during pregnancy, including 88 during the period of fetal organogenesis. There were no differences in maternal history, birthweight, gestational age at delivery, and rates of livebirths, spontaneous or therapeutic abortions, fetal distress, and major or minor malformations among groups. It is concluded that exposure to cisapride during pregnancy is not associated with a major increased risk of malformations or spontaneous abortions or with decreased birthweight.

Abnormalities, Drug-Induced↗
PubMed1997

Intrauterine device localization by three-dimensional transvaginal sonography.

Our objective was to investigate the possible role of three-dimensional transvaginal ultrasound in the visualization of an intrauterine device (IUD) for routine follow-up after insertion. A total of 96 women were examined after insertion of a TCu380A IUD. Three-dimensional ultrasonographic imaging was carried out using a special vaginal probe and a commercially available ultrasound machine at a mean interval of 22 days after insertion. Complete simultaneous imaging of all parts of the IUD was possible in 95% of cases. In the three-plane mode, all parts of the IUD could be visualized in 64% and in a further 30 cases this was possible only after volume rendering. In two women, incomplete opening of the two arms of the device was demonstrated. In one of these cases, the entire IUD was displaced into the cervical canal. In another case, an intrauterine pregnancy was found together with an IUD in the correct position. Three-dimensional ultrasound provides useful information on the location of the IUD following insertion. It enables imaging of the entire IUD, i.e. the shaft and the arms, simultaneously. Additionally, the examination time can be kept to a minimum with this new technique.

Adult↗
PubMed1997

Isolation of Chlamydia pneumoniae from a carotid endarterectomy specimen.

Chlamydia pneumoniae has been associated with atherosclerotic cardiovascular disease by both seroepidemiologic studies and direct detection of the organism in atherosclerotic plaque by electron microscopy (EM), immunocytochemistry (ICC), and polymerase chain reaction (PCR). Despite the frequent detection of the organism in atheromatous cardiovascular specimens by these methods, only 1 cardiovascular isolate of C. pneumoniae, obtained from a coronary artery, has been previously reported. This study reports the isolation of C. pneumoniae from a prospectively obtained carotid endarterectomy specimen. The organism appears to be identical to other C. pneumoniae isolates by EM morphology, reactivity to species-specific monoclonal antibodies, and Southern hybridization analysis of chromosomal digests using C. pneumoniae-specific DNA probes. C. pneumoniae was detected by PCR or ICC (or both) in 11 (69%) of 16 other endarterectomy specimens tested by both of these methods. These results provide further evidence for an association of C. pneumoniae and atherosclerosis by confirming the presence of viable bacteria within atherosclerotic plaque.

Chlamydophila pneumoniae↗
PubMed1997

Vascular endothelial growth factor production by human luteinized granulosa cells in vitro.

Vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) originating from the follicle or corpus luteum may be a physiological regulator of ovulation and neovascularization of luteinizing tissue, as well as a pathological factor in the development of ovarian hyperstimulation syndrome (OHSS). The objective of this study was to quantify VEGF production by human luteinized granulosa cells in vitro and to determine if gonadotrophin stimulates VEGF production directly and/or indirectly via enhanced synthesis of progesterone. In study 1, luteinized granulosa cells collected from women undergoing ovarian stimulation for in-vitro fertilization were cultured in the presence and absence of human chorionic gonadotrophin (HCG; 100 ng/ml) and/or low density lipoprotein (LDL; 100 microg protein/ml). In study 2, the progesterone synthesis inhibitor trilostane (250 ng/ml) and/or a progesterone receptor antagonist ZK137.316 (3.2 microM) were also added. Medium was harvested on days 1, 3, 5, 7 and 9 of culture and assayed for VEGF and progesterone. Results of study 1 were divided into two categories based on control concentrations of VEGF on day 1: 'low producers' (n = 6; <750 pg VEGF/ml) and 'high producers' (n = 5; >1000 pg VEGF/ml; P < 0.01). VEGF concentrations in cultures of both low and high producers increased (P < 0.01) from day 1 to maximal values on day 3, then steadily declined through to day 9. Chronic exposure to LDL or HCG increased (P < 0.05) VEGF concentrations in cultures of low producers by day 3 and day 5 respectively. In contrast, LDL did not alter VEGF concentrations in cultures of high producers and HCG did not increase VEGF concentrations until day 7. Nevertheless, acute exposure to HCG beginning on day 7 increased (P < 0.05) VEGF concentrations 3-fold in cultures of low or high producers. In study 2, trilostane treatment decreased (P < 0.05) progesterone concentrations by 91% on day 1 of culture but had no effect on VEGF concentrations on any day. ZK137.316 alone or with trilostane did not affect VEGF synthesis. These results suggest that VEGF production by luteinized granulosa cells is enhanced by gonadotrophin (HCG) independent of gonadotrophin-stimulated progesterone synthesis. These data are consistent with the hypothesis that the exacerbation of OHSS in early pregnancy is mediated by the CG stimulation of luteal VEGF production.

Adult↗
PubMed1997

Primary low-grade endometrial B-cell lymphoma.

We describe three cases of primary low-grade B-cell lymphoma of the endometrium and contrast the histological, immunohistochemical, and molecular features with two examples of benign endometrial lymphoid infiltrates. The first case was an incidental finding in a curettage specimen, confirmed on a subsequent hysterectomy. The other two cases of lymphoma were incidental findings on hysterectomy procedures performed for prolapse and cervical dysplasia, respectively. All three lymphomas occurred in patients in their sixties; none formed gross tumors. Histologic examination revealed lymphoid nodules adjacent to endometrial glands. The lymphoid cells showed mild nuclear enlargement and slight irregularities of the nuclear contour. None of the three patients had evidence of disease outside the endometrium by physical examination, bone marrow biopsy, or sampling of pelvic lymph nodes. Immunohistochemistry demonstrated a B-cell phenotype of the lymphoid cells (CD20 positive, CD79a positive) with aberrant coexpression of the T-cell-associated marker CD43. Polymerase chain reaction (PCR) amplification of the VDJ region of the immunoglobulin heavy-chain was performed on DNA isolated from paraffin sections. These studies demonstrated a clonal proliferation of B-lymphocytes in two cases. In the third case, a faint band was found superimposed on a background smear, suggesting the presence of a B-cell clone. In contrast, the two examples of histologically benign lymphoid aggregates of the endometrium consisted predominantly of T cells with rare B-lymphocytes; there was no evidence of coexpression of CD43 by B-cells. The PCR amplification from the benign lymphoid aggregates did not support a clonal process. Primary lymphoid neoplasms of the endometrium are rare, and all cases described so far have been high-stage, high-grade neoplasms. To our knowledge, this is the first report of primary low-grade B-cell lymphoma of the endometrium, presumably arising from endometrial lymphoid tissue.

Aged↗
PubMed1997

Are there "autistic-like" features in congenitally blind children?

Twenty-four congenitally blind children between 3 and 9 years of age were studied for the prevalence of "autistic-like" features, as assessed by teacher reports and by systematic observations of the children's behaviour. A comparison between the 15 blind children who had IQs over 70 and 10 sighted children group-matched for age and verbal ability revealed that a number of autistic-like features were more common in the blind. When the nine blind children who had IQs less than 70 were compared with nine group-matched autistic children, the picture that emerged was of substantial overlap in clinical presentation, despite subtle differences on clinical impression. Similar results were obtained when blind subgroups were reconstituted according to the children's nonautistic or autistic-like clinical presentation, rather than IQ. These findings are discussed in relation to competing theories concerning the development of autism and "theory of mind".

Autistic Disorder↗