Search PubMed⌕ Search

Biomedical subjects

W Brown

Publications and source records attributed to W Brown.

At least 73 records · Page 4Linked to original sources
PubMed1996

Ownership and uses of human tissue: does the Nuffield bioethics report accord with opinion of surgical inpatients?

OBJECTIVE: To compare opinion of surgical inpatients with the conclusions of the report of the Nuffield Council on Bioethics regarding the ownership and uses of human tissue. DESIGN: Survey of results of questionnaires completed by patients. SETTING: Large teaching hospital. SUBJECTS: 384 postoperative adult surgical patients. RESULTS: There was strong support among patients for the use of tissues in medical education, research, and science with the exception of those tissues which may transmit disease to others. Few patients (39; 10%) believed that they retained ownership of tissue removed at surgery. Most believed that the tissue belonged to the hospital (103; 27%), to nobody (103; 27%), or to the laboratory (77; 20%). Most patients had not been given any information about the possible uses of their tissues after removal. CONCLUSIONS: Surgical inpatients seem to endorse the conclusions of the Nuffield report regarding the ownership and uses of human tissue. The recommendations regarding patient information and consent procedures should be implemented at the earliest opportunity.

Adult↗
PubMed1996

Mammalian artificial chromosomes.

The development of candidate vectors and of techniques for their manipulation by sequence targeting suggest that a mini-chromosome vector system for the mouse germline may be at hand. Mini-chromosome vectors should allow new sorts of genetic problems to be addressed experimentally and may accelerate the process of gene identification.

Journal Article↗
PubMed1996

Production of an extracellular polysaccharide by Agrobacterium sp DS3 NRRL B-14297 isolated from soil.

A bacterium isolated from soil and identified as Agrobacterium sp produced a water-soluble extracellular polysaccharide capable of producing highly viscous solutions. Gas chromatographic analysis revealed a sugar composition of glucose, galactose and mannose in the molar ratio of 7.5:2.4:1, together with 3.7% (w/w) pyruvic acid. Methylation analyses showed the presence of (1-->3)-, (1-->4)- and (1-->6)-linked glucose, (1-->3)- and (1-->4, 1-->6)-linked galactose and a small portion of (1-->3)-linked mannose residues. Succinic acid was not present. The molecular weight of the polysaccharide was estimated by light scattering to be 2 x 10(6) Da. The viscosity of solutions containing the polysaccharide remained constant from pH 3 to 11, and decreased by 50% when heated from 5 to 55 degrees C. Maximum yield of the polysaccharide, 20 g L-1, was reached in 48 h at 30 degrees C incubation.

Carbohydrate Conformation↗
PubMed1996

Mammalian artificial chromosomes.

The development of candidate vectors and of techniques for their manipulation by sequence targeting suggest that a mini-chromosome vector system for the mouse germline may be at hand. Mini-chromosome vectors should allow new sorts of genetic problems to be addressed experimentally and may accelerate the process of gene identification.

Animals↗
PubMed1995

Children with a schizophrenic disorder: neurobehavioral studies.

This paper summarizes retrospective and cross-sectional neurobehavioral studies of schizophrenic children. Retrospective studies of schizophrenic children reveal that during early childhood, prior to the first onset of schizophrenic symptoms, most schizophrenic children showed delays in language acquisition and/or impairments and delays in visual-motor coordination. These impairments appear to be developmental delays rather than fixed neurobehavioral impairments, because cross-sectional studies conducted when the children are at least 10 years of age, after the first onset of psychosis, fail to detect the same deficits. The results of behavioral, cognitive/neuropsychological studies as well as the study of event-related potentials measured during performance of cognitive tasks suggests that schizophrenic children suffer from limitations in processing resources. It is argued that the developmental delays observed in schizophrenic children represent the greater time it takes them to automate certain skills. The delay in automation may reflect their limited information-processing capacity.

Brain↗
PubMed1995

Domestic violence experienced by women attending an accident and emergency department.

The aim of the study was to establish the extent and severity of domestic violence experienced by women attending the accident and emergency department of a large teaching hospital in Newcastle. The data were collected over a five-week period in 1992. All women between 17 and 80 years, attending the emergency or ambulatory areas between 8 a.m. and midnight, were asked to complete a confidential structured interview. A total of 401 women participated in the study, representing 82 per cent of eligible women approached. Each participant was asked if she had ever been physically hurt by someone close to her. Questions were asked to determine the relationship to the perpetrator, the type and cause of injury, treatment necessary and help sought. Seven (1.7 per cent, 95 per cent confidence interval (CI) 0.46 to 3.02) of the women surveyed were attending the hospital as a direct result of an incident of domestic violence, and 100 women (25 per cent, CI 21 to 29) had experienced domestic violence at some time. Bruising, fractures and cuts were the most common forms of injury, with the most common locations being the head, face and chest. Weapons, such as guns and knives, were used in 20 per cent of the incidents. A considerable number of the women (68 per cent) did not seek help at the time of their injuries. As a substantial proportion of women have experienced domestic violence in their lives, accident and emergency workers should receive training in recognising and assisting victims of domestic violence.

Adolescent↗
PubMed1995

Bacteriology of urinary tract stones.

It has been reported that up to half of renal stones and associated urine specimens have been positive on culture, and that up to 50% of such stones contain magnesium ammonium phosphate. In a prospective study using infrared and wet chemical analysis, we found positive cultures in only 7 of 132 renal, 5 of 105 ureteral and 6 of 21 bladder stones obtained surgically and handled with sterility. Of the culture positive calculi only 43% from the kidney, none from the ureter and 50% from the bladder contained detectable magnesium ammonium phosphate. However, magnesium ammonium phosphate was detectable in 20% of renal, 2% of ureteral and 27% of bladder stones with negative cultures. Of the culture positive renal and ureteral calculi 42% were predominantly calcium phosphate and 17% were predominantly calcium oxalate. For culture negative stones 25% and 51% from the kidney, and 15% and 82% from the ureter were composed of predominantly calcium phosphate and calcium oxalate, respectively. Among the culture positive stones, related positive urine cultures were noted in 100% of the renal, 20% of the ureteral and 50% of the bladder cases, compared to 26%, 10% and 27%, respectively, of culture negative calculi. The same organism was found in the stone and urine in only 38% of the cases. The lower frequency of positive urine cultures, of stones with magnesium ammonium phosphate, and especially of culture positive renal and ureteral stones (5%) than in previous reports suggests that stone culture may be of less value than indicated previously, except for bladder calculi and large renal stones, such as the branched type.

Adult↗
PubMed1995

Midfoot fractures.

Midfoot fractures, which include injuries to the tarsal navicular, cunieforms, and the cuboid, are uncommonly detected. Prompt diagnosis and appropriate treatment of these fractures are essential for maintaining normal foot biomechanical function. This article reviews various midfoot fractures.

Fractures, Bone↗
PubMed1994

Filipin and its interaction with cholesterol in aqueous media studied using static and dynamic light scattering.

Aggregation of filipin in aqueous medium and filipin-induced changes in cholesterol micelles have been studied using intensity and dynamic light scattering. The dependencies of filipin aggregate dimensions on concentration, solvent, and temperature were studied, and revealed that the aggregates do not have a well-defined geometry, i.e., a critical micelle concentration cannot be detected and stable structures are not formed. The aggregates are of size Rg approximately 110 nm and Rh approximately 63 nm, referring to the radius of gyration and hydrodynamic radius, respectively. In the concentration range studied (1 microM < C < 30 microM), a low molecular weight species (monomer/dimer) is always present together with the aggregates. In ethanol/water mixtures, large (Rg approximately 500 nm), narrow distribution aggregates are formed in the water volume fraction range 0.45 < phi H2O < 0.65. Aggregation also occurs on changing the temperature; In the range 7-37 degrees C, smaller aggregates (10-30 nm form and the process is only partially reversible. No pronounced effect of filipin on the structure of the cholesterol micelles was observed (a small increase in Rg and Rh is noted). These results rule out any "specificity" for the filipin interactions with cholesterol, which has been considered a key event in the filipin biochemical mode of action. A reevaluation of this question is suggested and some alternatives are advanced.

Biopolymers↗
PubMed1994

Transthoracic fine-needle aspiration biopsy cytology of pulmonary neoplasms.

The experience with 212 transthoracic fine-needle aspiration biopsy cytology specimens of mass lesions of the lung at a small Canadian hospital is reviewed. The technique showed a sensitivity of 78.0%, a specificity of 85.7%, a positive predictive value of 98.5%, and a negative predictive value of 25.0% when the cytological diagnoses were compared with the final clinicopathological diagnoses listed in the patients' charts. There was only one false positive diagnosis of malignancy. Diagnoses based on cytology of the aspirates were compared with histological diagnoses in 127 cases and the accuracy of typing of the major groups of carcinoma was assessed. Distinction between small-cell carcinoma and non-small-cell carcinoma was usually accurate and fairly good correlation was achieved for all major types of carcinoma. The results for typing of the neoplasm are not as good as those from larger centres in the world. The technique is considered to be useful even in the setting of a small hospital.

Biopsy, Needle↗
PubMed1994

Self-discrepancies and perceived peer acceptance.

We examined developmental changes in the self and the relationship between such changes and perceived peer acceptance in a sample of 414 6- to 11-year-old Australian children (211 boys, 203 girls) who completed a self-discrepancy scale and a perceived peer acceptance scale specifically constructed for this study. Resulting scores suggested that critical periods in developmental changes in the structure of the self occur at about 7 to 8 years and that a relationship exists between the reporting of a comparative large number and a larger size of discrepancies and a perception of lack of peer acceptance.

Age Factors↗
PubMed1994

Induction of systemic immunologic hyporesponsiveness to ovalbumin in neonatal rats by the enteric administration of peptic fragments of ovalbumin.

The orogastric administration of protein antigens can induce specific systemic immunologic hyporesponsiveness to the antigens. Some evidence has suggested that fragmention of the antigens by proteolytic enzymes in the gastrointestinal tract is a necessary step in this phenomenon. We administered either ovalbumin (OVA) or fragments OVA, produced by digestion with pepsin, into the stomach or jejunum of suckling rats and measured the serum IgG antibody response to a subsequent intraperitoneal challenge with OVA. Whereas OVA administered by gastric gavage caused virtually a complete unresponsiveness to the OVA challenge, administration into the jejunum had no significant effect. Administration of peptic fragments of OVA (about 8000 Da) into either the jejunum or stomach caused systemic unresponsiveness in 62% and 67% of animals, respectively (p < .05 vs buffer-fed controls). Smaller fragments of OVA (< 2000 Da) given into the stomach or jejunum had no effect on systemic IgG responses, nor did administration of the 8000 Da fragments intraperitoneally. We conclude the 1) systemic immunologic tolerance to OVA can be induced by enteric administration of critical-size fragments of OVA, and 2) encounter of the OVA fragments, like intact OVA, via the gut yields a distinctly different response from that which follows parenteral administration.

Animals↗
PubMed1994

Endogenous serum antibodies that interfere with a common thyroid hormone uptake assay: characterization and prevalence.

We identified individuals whose serum contained a substance that produced falsely decreased thyroid hormone (T)-uptake values determined by the Emit (Syva) procedure. Investigation of this interference was prompted by identification of a patient with T-uptake values inconsistent with clinical assessment. IgG depletion and supplementation studies with this patient's serum suggested that the interference was due to endogenous antibodies with specificity for the thyroxine-glucose-6-phosphate dehydrogenase conjugate in the Emit T-uptake assay. The prevalence of the interference was examined by prospectively comparing routine Emit T-uptake values of 1710 patients' samples to T-uptake values obtained by another method. Discrepant samples were also assayed by a radioactive binding triiodothyronine-uptake assay. We identified eight samples that had falsely decreased T-uptake values by Emit, for an overall prevalence of 0.46%. Among 45 consecutive patients with a T-uptake value < 20%, five patients, or 11%, were falsely decreased by Emit and three of these were clearly due to an interfering IgG. We suggest that samples with abnormally low T-uptake values determined by the Emit method be confirmed by an alternative method.

Adult↗
PubMed1993

[Right diaphragmatic paralysis after liver transplantation].

Right hemidiaphragm paralysis has been previously documented in patients after orthotopic liver transplantation (OLT) and it may contribute to the development of postoperative pulmonary problems. It has been postulated that a crush injury to the right phrenic nerve during OLT is the cause of dysfunction of the right hemidiaphragm. To assess the incidence and effect of right phrenic nerve injury after OLT, we prospectively studied 51 adult liver recipients that we compared with twelve patients who underwent liver resection (LR) without suprahepatic vena cava clamping. We studied the diaphragm excursion by ultrasound, the pulmonary function tests and the transcutaneous phrenic nerve conduction. Righ phrenic nerve injury and hemidiaphragm paralysis occurred respectively in 79% and 38% of the liver recipients but not after LR. Conduction along the right phrenic nerve was absent in 53% of the patients and reduced in another 26%. Left phrenic nerve conduction and left hemidiaphragm excursion were normal in both groups. Liver recipients with no conduction in the right phrenic nerve had a significantly greater decrease in vital capacity in the supine position compared to those with some conduction (29% vs 14%; P < 0.001). However, neither the time on the ventilator or the hospital stay were significantly different between the two groups. Complete recovery of phrenic nerve conduction and diaphragm function may take up to nine months. Right phrenic nerve injury is common after OLT and causes right hemidiaphragm dysfunction.

Adolescent↗