Human red blood cell membrane damage by endosulfan

Endosulfan is a chlorinated hydrocarbon insecticide. Its in vitro toxicity on human red blood cell membrane was studied by staining with a fluorochrome dye, merocyanine-540 (MC-540) and Scanning Electron Microscopy (SEM). At a concentration of 0.001 microgram/ml (1 ppb) endosulfan was found to damage human red cell membranes as demonstrated by fluorescence of 30-50% of red cells on staining with MC-540. This was supported by the finding of crenation and threading of red blood cells under SEM. At concentration of 1 microgram/ml (1 ppm) the cells were markedly damaged.

Macrophage membrane alterations in leprosy as determined by change in sialic acid level

The level of sialic acid removable by neuraminidase from macrophages of bacteriologically-positive lepromatous leprosy (B(+)LL) patient is extremely low, compared to macrophages from tuberculoid leprosy patients or normal individuals. On the other hand macrophages from long term treated bacteriologically-negative lepromatous leprosy (B(-)LL) patients show a much higher level of sialic acid. This higher level is drastically reduced when these macrophages from (B(-)LL) patients are allowed to phagocytose Mycobacterium leprae. This modulation could be host- and pathogen-specific. It is demonstrated that M. leprae infection brings out membrane changes in the macrophages leading to alteration in the surface molecules. Such membrane changes may cause hindrance in the ability of macrophages to participate successfully in the immune process.

Heavy chain variable region. Multiple gene segments encode anti-4-(hydroxy-3-nitro-phenyl)acetyl idiotypic antibodies

The hapten (4-hydroxy-3-nitrophenyl)acetyl (NP), when conjugated to carrier proteins, elicits a characteristic idiotypic response (NPb) in C57BL/6 mice. The response can be divided serologically into two distinct NPb-positive groups of antibodies. The first group consists of four crossreacting subgroups (I-IV), the second of two subgroups (V, VI). Some antibodies of subgroups I and II have been shown to express the unmutated heavy chain variable region (VH) germline gene 186.2. Antibodies of subgroups V and VI crossreact extensively with the NPa-positive antibodies of BALB/c mice. We sequenced heavy chain complementary DNA from eight hybridomas producing anti-NP antibodies. Six of these belong to subgroups V and VI, and two were NPa-positive hybridomas of BALB/c origin. All sequences were homologous to each other, and differed by approximately 80 basepairs from the 186.2 C57BL/6 germline VH gene. From our sequence and Southern blot analyses we suggest: (a) the NPb idiotypic response is the product of several VH germline genes, (b) some of these genes are very homologous to the gene coding for the BALB/c NPa idiotype, and might represent the C57BL/6 allelic forms of this gene, (c) the diversity regions of NPb and NPa-positive antibodies are diverse in length and amino acid composition, except for the first residue, which is always tyrosine, (d) all four heavy chain joining region gene segments are expressed without mutation. We discuss our data in terms of diversity in the germline VH gene repertoire, as well as diversity created by gene segment-joining events and somatic mutation.

Peroxidation of the dried thin film of lipid by high-energy alpha particles from a cyclotron

High-energy alpha particles produced a dose-dependent linear increase in different lipid peroxidation products (e.g., malondialdehyde (MDA), conjugated dienes, and hydroperoxides) in the dried thin film state. An inverse dose-rate effect was observed when the dose rate was varied by changing either the alpha-particle fluence rate or the alpha-particle energy. The antioxidants alpha-tocopherol and butylated hydroxytoluene (BHT) suppressed the alpha-particle-induced lipid peroxidation in the dried thin film state, and in this respect alpha-tocopherol was found superior to BHT. It was found that alpha-tocopherol was equally efficient in inhibiting lipid peroxidations by alpha particles and ultraviolet light.

Role of stressful life events in mania

The study investigated the role of stressful life events and family pathology in manic illness-selecting 30 cases of mania from Psychiatric Centre Jaipur and 30 normal controls from paramedical staff of psychiatric hospital. Both manics and normals were matched in terms of age, sex, education, marital status etc. All the subjects were subjected to Paykel's life events questionnaire, and an intensive psychiatric interview. Results revealed the significance of life stresses and family pathology in the genesis of mania. Death of close relative, financial difficulties, death of spouse, disappointment due to defeat in election, turned out to be major life events in contribution of manic pathology.

Electrocardiographic changes in multi bacillary leprosy

14 cases of multi bacillary leprosy (BL and LL) were investigated biochemically and ECG recording was done. Serum cholesterol was found to be raised in 4 out of 14 cases and SGOT was raised in 2 cases. P wave, PR interval and QRS complex did not show any changes, ST segment was depressed in 2 cases, T wave was flat in 2 cases and inverted in one case and Q-Tc interval was prolonged (more than 0.40 secs) in 3 cases.

Lipid peroxidation by ultraviolet light and high energy alpha particles from a cyclotron

High energy alpha-particles (approximately 16 MeV) and 254 nm ultraviolet light produced dose dependent linear increase of lipid hydroperoxides in the dried thin film state. For both types of radiation, an inverse dose-rate effect, i.e., a protracted radiation dose was more effective than a shorter, more intense one of larger size, was observed. Ultraviolet light (254 nm) produced higher yields of hydroperoxides in the aqueous liposomal suspension of lipid than in its dried thin film state.

Interaction of di-(2-ethylhexyl) phthalate with the pharmacological response and metabolic aspects of ethanol in mice

The interactions of di-(2-ethylhexyl) phthalate (DEHP) with the pharmacological response and metabolic aspects of ethanol in mice were investigated at oral doses of DEHP of 1.5, 3.0 and 7.5 g/kg or intraperitoneal doses of 3.7, 7.5 and 18.9 g/kg, administered once or daily for 7 days. A single oral or intraperitoneal administration of DEHP resulted in a significant increase in the ethanol-induced sleeping time, associated with an inhibition of alcohol dehydrogenase activity in liver; the effect of intraperitoneal administration was significant only at the highest dose. The activities of high and low Km aldehyde dehydrogenases in mouse liver were not affected by a single dose of DEHP by either route. Repeated oral doses of DEHP produced significant reductions in the ethanol-induced sleeping time and increases in the activities of alcohol and aldehyde dehydrogenases, whereas repeated intraperitoneal doses of DEHP significantly increased the sleeping time and decreased the activity of alcohol dehydrogenase, without any perceptible effect on the activities of aldehyde dehydrogenases. In vitro studies with mouse liver preparations revealed significant inhibition of alcohol dehydrogenase activity by mono-(2-ethylhexyl) phthalate and 2-ethylhexanol and of high and low Km aldehyde dehydrogenase activities by DEHP and mono-(2-ethylhexyl) phthalate at concentrations ranging from 0.03 to 1.00 mM. In all cases, in vitro enzyme inhibition by mono-(2-ethylhexyl) phthalate was most pronounced.

Pattern of cholera in Raipur: a twelve year appraisal

Outbreaks of cholera were recorded in Raipur in the years 1970, 1975, 1977 and 1979-1981. Change from V. cholerae classical inaba in 1970 to V. el tor ogawa in 1974 was also observed. The el tor strain is persisting in this area since then. In 1977, antigenic shift to V. el tor inaba was recorded but it again reverted to el tor ogawa which was responsible for outbreaks in 1979-1981. V. cholerae was isolated in most of the months in the years 1975, 1977 and 1980. Almost equal prevalence rates were seen in both sexes as well as in paediatric and adult groups. NAG vibrio were also inoculated. These data suggest endemicity of choloera in Raipur.

Influence of sex hormones on parathion toxicity in rats: antiacetylcholinesterase activity of parathion and paraoxon in plasma, erythrocytes, and brain

Administration of parathion resulted in a greater inhibition of acetylcholinesterase (AChE) activity of plasma, erythrocytes, and brain in female rats than in male rats. No sex-related difference was observed in the antiacetylcholinesterase activity of paraoxon, an active metabolite of parathion. Gonadectomy increased the susceptibility of males but had no perceptible effect on females, resulting in comparable inhibition of AChE by parathion in both sexes. Administration of testosterone led to recovery from increased sensitivity to the antiacetylcholinesterase activity of parathion in castrated males and afforded partial protection to ovariectomized females. On the other hand, administration of estradiol further enhanced the enzyme inhibition by parathion in castrated males but had no significant effect on that in ovariectomized females. Alterations in the status of sex hormones did not affect the antiacetylcholinesterase activity of paraoxon in plasma and erythrocytes. However, inhibition of AChE activity by paraoxon was significantly higher in brains of gonadectomized rats than those of normal rats and the effect was reversible on administration of the respective sex hormones. The results indicate that testosterone plays an important role in determining parathion toxicity (as reflected by its antiacetylcholinesterase activity), probably by activating the oxidative cleavage of the insecticide into nontoxic metabolites.

DNA topoisomerase from Agrobacterium tumefaciens: purification and catalytic properties

The DNA topoisomerase from Agrobacterium tumefaciens has been purified to apparent homogeneity. The enzyme is a single polypeptide of about 100,000 in molecular weight. No apparent separation of the nicking and sealing activities could be obtained in attempts to separate the two activities by a variety of methods, including limited protease digestion, thermal denaturation, and differential inhibition. Monoclonal antibodies obtained from hybridomas likewise did not preferentially inhibit one of the two activities. These results suggest that the two catalytic functions are carried by the same essential residues of the active enzyme site.

Endogenous tumor growth factor indicated by increased ornithine decarboxylase activity in malignant cells treated with host serum ascites fluid

Ornithine decarboxylase (ODC) production was used as an indicator of mitotic activity in neoplastic cells removed from murine hosts at progressive stages of growth. Cells from three ascites cancers and one fibrosarcoma were tested and showed declining ODC production with progressive growth. The cells were incubated with serum or malignant effusion fluid taken from the murine hosts at progressive stages of growth. For 2 to 3 weeks after tumor implantation, sera and, in particular, ascites fluids increasingly stimulated ODC production in cells at all stages of growth. With advancing disease, without the malignant growth having reached a stationary phase, the collected fluids decreasingly stimulated ODC production in the cells. The stimulating factor(s) in host serum and malignant effusion fluid were not tumor specific in the one combination tested.

Effect of progressive neoplastic growth on the decarboxylation of DL-[1-14C]ornithine by lymphocytes from C3H/He tumor hosts

The reactivity of normal and tumor host lymphocytes incubated with normal serum or with serum or malignant ascites fluid from tumor hosts was measured by the ability of the lymphocytes to synthesize ornithine decarboxylase after phytohemagglutinin stimulation. Each of three tumors tested (a solid fibrosarcoma, an ascites mammary carcinoma, and an ascites ovarian carcinoma) caused increasing unresponsiveness in the lymphocytes of mice with progressing syngeneic neoplastic growth. The sera and particularly the malignant ascites fluids from mice given implants of the ascites cancers became progressively inhibitory to the activation of lymphocytes from tumor hosts as well as from normal mice. The serum from mice carrying s.c. implants of the fibrosarcoma enhanced the activation of lymphocytes from tumor hosts and from normal mice during early tumor growth before it also became inhibitory.

Serum therapy for radiation-induced impairment of immune resistance to metastasis

The use of serum transfusion to remedy radiation-induced damage to established antitumor resistance was investigated in female C3H mice. The mice, which had been actively immunized against a syngeneic mammary carcinoma, were injected i.v. and s.c. with suspensions of cells from the same tumor and were then given 300 R extensive-field irradiation to the abdomen two times. Tumor cells implanted outside the irradiated area grew better in irradiated mice than in unirradiated controls. Under these experimental conditions, protection could be transferred to radiation-impaired hosts with several injections of cell-free immune serum. Transfers of normal serum provided a detectable but low degree of protection. The corrective effect of serum transfers to radiation-impaired hosts was clearly expressed against pulmonary tumor growth (i.v. challenge), provided the transfusions were started no later than the first day after the injection of the tumor cells. Serum transfusions were ineffective against the growth of tumors implanted s.c. Transfers of serum from hosts carrying large (15 mm) s.c. tumor implants had a negative effect on the resistance of irradiated recipients. The results indicate that humoral resistance factors, both normal and immune, may act against metastatic spread of solid tumors.