Mechanisms of Bacillus cereus enteropathy

Three strains of Bacillus cereus isolated from sausages (Salami and Trekker, RANBAC, Ranchi) produced enterotoxin which caused vascular permeability in skin and haemorrhage in the ligated ileal loops of rabbits. Histopathological studies revealed haemorrhage and congestion in submucosa, mononuclear cell infiltration in lamina propria and submucosa and villous atrophy. Histochemical studies ruled out the effect on mitochondrial enzymes of intestinal epithelial cells. Purified enterotoxin given intradermally to rabbits caused severe necrotic reaction at the site of injection and death within 4 hr. Histopathological changes observed in liver included congestion of portal veins and sinusoids, vacuolar degeneration of hepatocytes, and hyperplasia of bile ducts. These suggested that B. cereus enterotoxin affected the capillaries of blood vessels locally and also systemically resulting into release of proteinaceous exudates and red blood cells.

In vivo and in vitro measurement of cell mediated immunity in Marek's disease: role of reticuloendothelial system

Dinitrofluorobenzene (DNFB) contact-sensitivity test and leucocyte adherence inhibition (LAI) test were performed in this study as in vivo and in vitro tests to measure the cell-mediated immunity (CMI) in chickens subjected to stimulation of reticuloendothelial (RE) system, depletion of RE system and other experimental groups after being challenged with Marek's disease (MD) virus. It was found that CMI was lower in the birds with depleted RE system and infected control birds, whereas CMI was higher in the birds with activated RE system and vaccinated birds as revealed by DNFB contact-sensitivity test. In cases of LAI test, the number of LAI-positive birds were highest in the chicks with depleted RE system particularly in 3rd and 4th month of age, when the incidence of MD was also maximum.

Pyogenic meningitis

Fifty cases with pyogenic meningitis, aged 15 to 72 years, with a male:female ratio of 5:1, were studied. The majority of cases (70%) were in the 15 to 25 years age group. The organisms detected in the 29 culture-positive cases included S aureus (12), pneumococci (9) and meningococci (8). Thirteen patients died; the poor prognostic factors included old age, the presence of coma or shock, CSF sugar below 10 mg/dl or protein above 750 mg/dl and the presence of gram negative organisms in the CSF.

Alterations in immunoglobulin & complement levels in chronic obstructive pulmonary disease

Thirty patients of chronic obstructive pulmonary disease (COPD; all smokers) and an equal number of controls (15 smokers) were studied. The COPD patients were further divided into group A (predominantly emphysema) and group B (predominantly bronchitis) of 15 patients each. Serum and sputum IgG, IgA and IgM and serum C3 and C4 were estimated. IgG, IgA, IgM and C3 and C4 were similar in smoker and non-smoker controls. Mean (+/- SD) serum IgG (IU/ml) was significantly higher in COPD patients (207.78 +/- 62.73) than in control (177.25 +/- 43.5; P less than 0.05), serum IgA (IU/ml) was also significantly higher in COPD (205.04 +/- 46.56) than in control (108.21 +/- 33.3; P less than 0.01). IgM was similar in the 2 groups. Sputum IgA (IU/ml) was higher in COPD (4.68 +/- 3.51) than in control (2.25 +/- 1.03; P less than 0.05). IgG and IgM were similar in the 2 groups. Both serum C3 (IU) and C4 (IU) were lower in COPD patients (C3 = 95.9 +/- 33.11, C4 = 113.6 +/- 62.4) than in control (C3 = 167.3 +/- 25.42, C4 = 205 +/- 76.5; P less than 0.05). Serum IgA in type B COPD (212.25 +/- 50.06) was higher than in type A (197.52 +/- 43.3; P less than 0.05) IgG and IgM were similar in these 2 groups. In COPD patients, immunoglobulins were either normal or higher indicating that deficiency of immunoglobulin is not a predisposing factor in development of COPD. Similar immunoglobulin values in smoker and nonsmoker controls indicated that smoking was not the cause of rise of immunoglobulins in COPD.(ABSTRACT TRUNCATED AT 250 WORDS)

Androgen assessment in hirsutism and alopecia

Advances in technology, such as saturation analysis and nonisotopic immunoassays, have improved the measurement of androgens, binding proteins, and hormone receptors, and clarified the diagnosis of idiopathic hirsutism. Immunoassay methods in steroid biochemistry enable accurate measurement of low concentrations of various androgens and their metabolites; and high-specificity antisera with chemical blocking agents allow measurement of these steroid directly in plasma without resorting to extraction methods. The future may bring the capacity to measure free concentrations.

Serum tumor markers of head and neck cancer: current status

The serum level of a variety of substances shows significant changes in head and neck cancer patients. Such substances are collectively called biochemical tumor markers. To date, most markers lack a high degree of specificity and sensitivity. However, serial measurement of markers showing elevated pretreatment levels may help in monitoring response to therapy. Other potential uses of tumor markers include earlier detection of recurrence and/or metastasis, and possible prediction of prognosis. Measurement of more than one marker seems to enhance the diagnostic accuracy of the test. Some markers show significant correlations with various immune parameters in head and neck cancer patients and may have a possible role in potentiating the immunodepressed status of such patients. A review of currently reported tumor markers in head and neck cancer showing their nature, sources, uses, and limitations is presented.

Treatment of androgenic disorders with dexamethasone: dose-response relationship for suppression of dehydroepiandrosterone sulfate

Glucocorticoids are effective in suppressing androgens in many women whose levels of these steroids are elevated. Their use has been controversial because of inconsistent reports about efficacy and concern about safety. We investigated the dose-response relationship for suppression of dehydroepiandrosterone sulfate (DHEAS) with the use of dexamethasone. Thirty women with an initial DHEAS value of greater than or equal to 300 micrograms/dl were studied. All had cystic or inflammatory acne, hirsutism, or androgenic alopecia. Dexamethasone was given as a single bedtime dosage of 0.125, 0.250, or 0.375 mg. Mean dosage required for suppression was 0.256 mg daily. Suppression of the DHEAS level to less than or equal to 200 micrograms/dl was achieved with 0.125 mg in 25% of women, 0.250 mg in an additional 50%, and 0.375 mg in a further 20%. Most patients were taking spironolactone when the study was performed. Effective suppression is attained with dexamethasone doses significantly lower than previously thought. Use of these doses was not associated with a significant incidence of adverse effects.

Lipid profile in smokers

In this study we observed that all the lipids except HDL cholesterol were higher in heavy smokers and those making for longer duration. HDL cholesterol was lower in smokers than nonsmokers. The changes in lipid profile were similar in cigarette and bidi smokers.

The role of the reticuloendothelial system in the immunopathology of Marek's disease

The role of macrophages in immunity against Marek's disease (MD) was studied. Chickens of one group were subjected to depletion of macrophages using repeated doses of Francil amorphous silica and those of another group were subjected to activation of macrophages using repeated doses of brewer's thioglycollate broth. Chickens of a third group were vaccinated with herpesvirus of turkeys FC 126 vaccine followed by depletion of macrophages. Chickens of these three groups, as well as groups of healthy unvaccinated and healthy vaccinated chickens, were challenged with virulent MD virus. A sixth group of healthy uninfected chickens was kept as a control. The results, based on clinical signs, gross and histopathological studies and agar gel precipitation test (AGPT) for antibodies, indicated that activation of macrophages enhanced immunity against MD and depletion of macrophages had the opposite effect. The protective effect of vaccination against MD was also lowered by depletion of macrophages. The results of AGPT indicated retardation of MD virus replication by macrophage activation and the reverse on depletion.

Combined clomiphene citrate (CC) and human menopausal gonadotropins (hMG) in a fixed schedule for follicular recruitment during in vitro fertilization: effects on premature luteinizing hormone (LH) surges

Recognizing the association between plasma progesterone (P) and an imminent LH surge, we investigated the frequency of P elevation in our stimulation protocol (clomiphene citrate-human menopausal gonadotropins). P was measured retrospectively on the day before, the day of, and the day after human chorionic gonadotropin hCG administration. The means +/- 2 standard deviations for P were as follows: day before hCG, 0.58 +/- 0.86; day of hCG, 0.64 +/- 0.56; and day after hCG, 1.47 +/- 1.22. Seven patients (8%) had P levels greater than 2 SD above the mean. Significant P elevations prior to hCG are infrequent with this protocol, and in the few patients with raised P a trend toward lowered fertilization was noted. The low incidence of P elevation may be secondary to the administration of hCG in a timely manner on the sixth day of estradiol (E2) rise.

In vivo immunosuppression by synthetic pyrethroid (cypermethrin) pesticide in mice and goats

Cypermethrin toxicity was produced in mice by intra-peritoneal injection of the pesticide at 50 mg/kg body weight per day for 26 days, and in goats by drenching with cypermethrin at 41.6 mg/kg body weight per day for 30 days. The status of cell-mediated immunity (CMI) was assessed by the 2,4-dinitrofluorobenzene (DNFB) skin sensitivity test. The results indicated significant depression of CMI in the cypermethrin-treated mice and goats. In addition, the humoral immune reaction of the goats intoxicated with cypermethrin was estimated by enumeration of the plaque-forming B-lymphocytes. The rate of plaque formation in the lymphocyte suspension of cypermethrin-treated goats was significantly reduced and the diameter of the plaques was also significantly lower than in that of control animals. The results indicated that cypermethrin suppressed both CMI and the antibody-forming ability of lymphocytes. This immunosuppressive action of cypermethrin is being reported for the first time.

Steroid receptors in human brain and spinal cord tumors

Previous investigators have shown evidence of hormonal receptor protein in human brain tumors. In spite of conflicting results, antiestrogen agents (e.g., tamoxifen) have been used in clinical trials of recurrent unresectable meningiomas. In an effort to accrue further comprehensive in vitro data on this subject, we have evaluated 50 human brain and spinal tumors for estrogen, progesterone, and androgen receptor markers. Twenty-nine of the 50 tumors were meningiomas. The other 21 included 11 gliomas of various grades, 5 schwannomas, 3 metastatic carcinomas, 1 angiofibroma, and 1 craniopharyngioma. Only 8 tumors, all meningiomas, were positive for both progesterone and androgen receptors. The 8th tumor was positive for all three receptor proteins. Our study did not find a significant relationship between meningiomas and the presence of steroid receptor protein. We conclude that the use of antiestrogen agents is not indicated in the treatment of meningioma. No significant relationship to sex, menopausal status, tumor type, or tumor location was observed.

Recent advances in laboratory tests for autoantibodies to thyrotropin receptor protein in Graves' disease

Graves' disease is characterized by the presence of autoantibodies with variable reactivities to TSH receptor protein. These autoantibodies are heterogeneous in nature and may act as TSH agonists or infrequently as TSH antagonists (blocking antibodies). With new technical advances, it has become possible to quantitate these antibodies and their reactivities in clinical laboratories. Technical aspects of these assays and their clinical utility in the diagnosis and management of patients with Graves' disease are discussed.

Measurement of immunoreactive myelin basic protein peptide (45-89) in cerebrospinal fluid

To measure myelin basic protein (MBP)-like material in cerebrospinal fluid, we compared two radioimmunoassays, both using the same antiserum to MBP but one using peptide (45-89) as the radioligand and standard (peptide assay), and the other using purified MBP as the radioligand and standard (MBP assay), with respect to their diagnostic sensitivity. Cerebrospinal fluid specimens from 185 patients with definite multiple sclerosis (MS) (n = 27), possible MS (n = 63), probable MS (n = 24), and other neurological disease (n = 71) were analyzed using both assays. The diagnostic sensitivity of the peptide assay was significantly better than that of the MBP assay in those with definite MS (sensitivity 59% and 30%, respectively); there was no significant difference in specificity. The peptide assay also showed better correlation with disease activity than the MBP assay: 14 patients classified as having active MS showed significantly higher sensitivity (78.6% versus 38%, p less than 0.04) when compared to patients with inactive disease. The MBP assay showed no significant difference between these two groups. Besides the increase in sensitivity, the actual molar concentrations of immunoreactive MBP detected using this peptide assay were considerably higher than those found using the MBP assay. These results show that the use of MBP antisera capable of recognizing epitopes present in the carboxyl half of MBP peptide (45-89) results in more sensitive detection of immunoreactive MBP when used with MBP peptide (45-89) as radiolabeled ligand in the assay.

Volume correction factor in time dose relationships in brachytherapy

Paterson's clinical data about the maximum tolerance doses for various volumes of interstitial implants with Ra-226 delivered in seven days was made use of in deriving volume correction factors phi v and phi'v for TDF and CRE concepts respectively for brachytherapy. The derived volume correction factors phi v for TDF and phi'v for CRE differ from the from the one assumed for CRE by Kirk et al. and implied for TDF by Goitein. A normalising volume of 70 cc has been suggested for both CRE and TDF concepts for brachytherapy. A table showing TDFv, the volume corrected TDF, is presented for various volumes and dose rates for continuous irradiation. The use of this table is illustrated with examples.