Search PubMed⌕ Search

Biomedical subjects

A George

Publications and source records attributed to A George.

At least 91 records · Page 5Linked to original sources
PubMed1997

The recognition of haemoglobin by antibodies raised for the immunoassay of beta-amyloid.

Canine and porcine cerebrospinal fluid (CSF) were fractionated by size exclusion chromatography and analysed by a luminescence enzyme linked immunosorbent assay (ELISA) configured to detect beta-amyloid. A peak of activity was observed in the CSF consistent with the molecular weight of beta-amyloid. When CSF contaminated with blood was analysed an additional peak of immunoreactivity at a higher molecular weight was observed. The peak of activity was found to be derived from cross-reactivity of the immunoglobulins employed in the ELISA with haemoglobin. These findings are discussed with reference to primary and structural sequence homology between beta-amyloid and haemoglobin from a number of species, the known properties of beta-amyloid and recent clinical reports.

Amyloid beta-Peptides↗
PubMed1997

[Myasthenic crisis caused by azathioprine-induced fever].

Azathioprine is an established immunosuppressive agent in the treatment of myasthenia gravis. In rare cases, complications such as hypersensitivity reactions including fever may occur. A 73-year-old patient with the first manifestation of myasthenia gravis was immunosuppressed with azathioprine and prednisolone in addition to pyridostigmine treatment and discharged from hospital without symptoms. Ten days after onset of azathioprine therapy, he developed fever and a myasthenic crisis requiring artificial ventilation. Azathioprine was discontinued. Microbiological and radiological examinations revealed no signs of infection. After clinical improvement azathioprine was re-started, and following a single dose the patient again presented with fever and tachycardia. Azathioprine was discontinued, and all symptoms abated within a day. These symptoms were most probably caused by an azathioprine-induced hypersensitivity reaction. Life-threatening myasthenic crises may occur if such a hypersensitivity reaction remains unrecognized in patients with myasthenia gravis.

Aged↗
PubMed1997

Tuberculosis in Bombay: new insights from poor urban patients.

This study explores the health seeking behaviour of poor male and female tuberculosis patients in Bombay, and examines their perceptions of the causes and effects of the disease on their personal lives. Sixteen patients who attended an NGO's tuberculosis clinic were interviewed in-depth. Almost equal numbers of respondents stated 'germs' and 'worry' as the cause of tuberculosis. Men worried about loss of wages, financial difficulties, reduced capacity for work, poor job performance, and the consequences of long absence from work. Women were concerned about rejection by husband, harassment by in-laws, and the reduced chances of marriage (for single women), in addition to their concerns about dismissal from work. During the first two months of symptoms most patients either did nothing or took home remedies. When symptoms continued, private practitioners were the first source of allopathic treatment; they were generally unable to correctly diagnose the disease. Respondents shifted to municipal and NGO health services when private treatment became unaffordable. Respondents shifted again to NGO-based services because of the poor quality of municipal tuberculosis control services. The wage-earning capacity of both men and women was affected, but women feared loss of employment whereas men, being self-employed, lost wages but not employment. Married men and single women perceived a greater level of family support to initiate and complete treatment. Married women tried, often unsuccessfully, to hide their disease condition for fear of desertion, rejection or blame for bringing the disease. Women dropped out from treatment because of the pressure of housework, and the strain of keeping their condition secret particularly when the reasons for their movements outside the home were routinely questioned. Health programmes will have to be sensitive to the different needs and concerns of urban men and women with tuberculosis; in the case of women, health care providers will have to make particular efforts to identify and treat married women with tuberculosis completely.

Attitude to Health↗
PubMed1997

Exercise avoidance and impaired endurance capacity in patients with panic disorder.

Exercise habits and indices of aerobic fitness as measured by spiroergometric testing were examined in 38 patients with panic disorder and/or agoraphobia and 24 untrained healthy controls. Maximal oxygen consumption, maximal power output and the power output at a lactate concentration of 4 mmol/l were significantly reduced in the patient group when compared to untrained controls. Other parameters like physical work capacity at a heart rate of 150/min, maximal lactate concentration, vital capacity, subjective exertion at maximal work load, and maximal heart rate did not differ between patients and controls. Patient interviews revealed that aerobic exercise is avoided by the vast majority of patients. Reduced aerobic fitness might contribute to the pathophysiology of panic disorder and/or agoraphobia.

Adolescent↗
PubMed1997

Magnetic resonance imaging in the congenital adrenal hyperplasia population: increased frequency of white-matter abnormalities and temporal lobe atrophy.

Congenital adrenal hyperplasia results from an adrenal enzyme deficiency, that causes an underproduction of glucocorticoids and sometimes mineralocorticoids and a resultant overproduction of androgens, until treatment with replacement glucocorticoids is instituted. The goal of this study was to determine the frequency and etiology of white-matter changes and temporal lobe atrophy demonstrable on magnetic resonance imaging (MRI) in a group of children and young adults with congenital adrenal hyperplasia. About one third of the patients evidenced white-matter abnormalities or temporal lobe atrophy. All patients, except one with a known stroke, had normal neurologic examinations. Exposure to excess exogenous glucocorticoids in the process of being treated for congenital adrenal hyperplasia is the most theoretically appealing explanation for these MRI findings. However, the relationship of MRI findings to treatment status (over-versus under-suppressed) does not run in clear parallel.

Adolescent↗
PubMed1997

[Value of sports in treatment of psychiatric illness].

Several studies in healthy volunteers have shown a positive effect of endurance training on anxiety, depressive symptoms, self-esteem, concentration and stress tolerance. There are only a few controlled studies examining the therapeutic potential of exercise in psychiatric disorders. However, there is good evidence that exercise is effective in mild to moderate depression and in anxiety disorders. The therapeutic effect did not correlate with changes in cardiopulmonary fitness in the majority of studies. Therefore, other neurobiological and psychological mechanisms are discussed which might explain the effectiveness of regular physical training. The authors offer a variety of suggestions, how exercise could be integrated and evaluated in the treatment of psychiatric disorders.

Anxiety Disorders↗
PubMed1996

The carboxyl-terminal domain of phosphophoryn contains unique extended triplet amino acid repeat sequences forming ordered carboxyl-phosphate interaction ridges that may be essential in the biomineralization process.

Phosphophoryns (PPs), a family of Asp and Ser(P)-rich dentin proteins, are considered to be archetypal regulators of several aspects of extracellular matrix (ECM) biomineralization. We have cloned a rat incisor PP gene, Dmp2, from our odontoblast cDNA library and localized it to mouse chromosome 5q21 within 2 centimorgans of Dmp1, another tooth-specific ECM protein. The carboxyl-terminal region of Dmp2 protein (60 residue % Ser, 31 residue % Asp) is divided into two domains, one with unique repetitive blocks of [DSS]n,3</=14, the other with [SD]m = 2,3. Conformational analysis shows the phosphorylated form of the [DS*S*]n repeats to have a unique structure with well defined ridges of phosphates and carboxyls available for counter ion binding. The [S*D]m domains have different phosphate and carboxylate interaction edges and thus different calcium ion and apatite surface binding properties. These two domains and the colocalization of Dmp1 and Dmp2 genes at a position equivalent to the dentinogenesis imperfecta type II location on human 4q21 all suggest that the PPs are indeed involved in some aspect of ECM mineralization.

Amino Acid Sequence↗
PubMed1996

The V4-34 encoded anti-i autoantibodies recognize a large subset of human and mouse B-cells.

Autoantibodies to the i, I and Pr2 carbohydrate determinants bind red blood cells, preferentially at low temperature in vitro. Using multiparameter flow cytometric analyses, we demonstrate that each of these autoantibodies also react with human and mouse lymphocytes at physiologic temperatures. The anti-Pr2 autoantibody recognizes a glycoprotein determinant(s) expressed by a subset of both T and B lymphocytes. In contrast, the binding of anti-i and anti-I antibodies each is restricted to B-lymphocytes. The anti-i autoantibody binds to over 50% of all B cells, whereas the anti-I antibody reacts with less than 10% of either tonsillar or blood B cells. Prior studies identified that the B cell isoform of CD45 (B220) has the linear poly-N-acetyllactosamine that forms the "i" determinant. Because anti-B220 antibodies recently have been reported to influence T-dependent B-cell isotype switching, we tested each antibody for its ability to influence the production of secondary Ig isotypes by murine splenocytes co-cultured with a stimulator helper T cell clone. We find that addition of anti-i antibody increases the proportion of B cells secreting secondary Ig isotypes. In contrast, the anti-I antibody had no such effect. These findings imply that stimulation of B cells through the highly conserved carbohydrate determinant that forms the "i" antigen may be of physiologic importance in T-dependent B-cell differentiation.

Animals↗
PubMed1996

Early division of pedicled flaps using a simple device: a new technique.

A simple occlusion clamp with screws used to achieve early division of two-staged, distant pedicled flaps is presented. The device is applied to the bridge of a distant flap on the 5th postoperative day and is gradually tightened. It was used on 20 consecutive pedicled flaps in 20 patients: 5 abdominal flaps, 4 superficial external pudendal artery (SEPA) flaps, 9 cross leg flaps, 1 groin flap and 1 medial arm flap. In 17 patients, the flaps were divided successfully between the 9th to the 14th day (Mean: 10 days). The device was removed in 3 patients when ischaemic changes became apparent; their flaps however survived completely and were divided after a longer interval. The principles on which the device works, the technique, feasibility, and advantages of using the device for early flap division are discussed.

Adolescent↗
PubMed1996

Generation of gamma interferon responses in murine Peyer's patches following oral immunization.

To date, oral immunizations have been shown to generate only Th2 responses in murine Peyer's patches (PP), raising the possibility that T cells present in PP may be capable of mounting only Th2 responses or that the microenvironment of PP does not favor the generation of Th1 cells. However, it is also possible that antigens that can generate Th1 responses have not yet been used for oral immunizations. This study shows that T cells in PP of mice immunized orally with live Salmonella typhimurium secrete large amounts of gamma interferon (IFN-gamma) when they are stimulated with bacterial sonicate in vitro. Moreover, oral challenge of mice with live bacteria 4 months after immunization elicits a secondary IFN-gamma response in PP and mesenteric lymph nodes. Parenteral immunization does not generate an IFN-gamma T-cell response in PP, and parenteral challenge of orally immunized mice does not elicit a secondary response in PP. However, oral challenge of intraperitoneally immunized mice elicits a secondary IFN-gamma response in PP and mesenteric lymph nodes, and intraperitoneal challenge of orally immunized mice elicits a secondary response in the spleen. The data suggest that memory T cells recirculate between mucosal and nonmucosal compartments and that they may be recruited to the site of antigenic challenge.

Administration, Oral↗
PubMed1996

Echocardiographic assessment of left ventricular hypertrophy diastolic dysfunction and pericardial disease in patients on maintenance haemodialysis.

Echocardiographic study of sixty patients on maintenance haemodialysis (MHD) was undertaken to determine the prevalence and factors associated with left ventricular (LV) hypertrophy (LVH), LV diastolic dysfunction and pericardial disease. The mean age was 34.4 (standard deviation 13.0), range 14-66 years with 31 (51.7%) men. LVH was found in 41 (68%) patients. Of the factors analysed, serum calcium and calcium-phosphate product were significantly associated with LVH (t = 2.01, df = 58, p = 0.046; t = 2.18, df = 58, p = 0.032 respectively). Hypertension in this study was not significantly associated with LVH (p = 0.169). LV diastolic dysfunction was found in 23/41 (56%) patients with LVH, and in 9/19 (47%) patients without LVH (difference is not statistically significant, X2 = 0.12, df = 1, p = 0.725). Small pericardial effusions were detected in 4/60 (7%) patients and two patients had pericardial thickening. We conclude that in our MHD patients LVH, is very common and that diastolic dysfunction is observed equally in patients with and without LVH. However, haemodynamically significant pericardial effusions are rare in patients who have been on dialysis for at least six months.

Adolescent↗