Serotonergic mechanisms in heart failure

A total of 29 subjects were studied which included 18 heart failure and 11 matched control cases. The underlying heart disease in heart failure cases was mostly chronic rheumatic valvular disease. The diagnosis of heart disease and heart failure was made on the basis of clinical examination, supplemented by electrocardiography, chest skiagram and echo cardiography. The serotonin status was assessed by measuring platelet serotonin uptake, intraplatelet serotonin content and whole blood 5-hydroxytryptamine (5-HT) levels. Blood platelet count was also done. In heart failure cases, platelet count were significantly less, the platelet 5-HT uptake and blood 5-HT levels remain unaltered. These findings indicate that platelet pool of serotonin does not contribute to raised serotonin blood levels in heart failure. The high blood serotonin levels may be due to either clearance defect or enhanced secretion from the gut or both. The altered serotonin kinetics in platelets also indicate a state of platelet activation in heart failure.

Serum trace elements and Cu/Zn ratio in malignant lymphomas in children

Serum copper and zinc levels, and Cu/Zn ratio were measured in 40 children with Hodgkin's (n = 18) and non-Hodgkin's (n = 22) lymphomas, and 30 controls using Atomic Absorption Spectrophotometry. The mean serum copper levels were higher in lymphoma patients than in controls (199.8 micrograms/dl v. 95.8 micrograms/dl) P < 0.001). The increase in serum copper level correlated with the stage of disease being maximum in Stage IV (219.4 micrograms/dl v. 143.2 micrograms/dl) (P < 0.01). On the other hand, there was a decrease in the serum zinc levels in lymphoma patients as compared to controls (86.1 micrograms/dl v. 117.4 micrograms/dl) (P < 0.001), but this was significant only in patients with advanced disease. The Cu/Zn ratio was therefore markedly increased in these patients (2.46 v. 0.83) (P < 0.001). Following successful treatment the abnormal serum copper and zinc levels returned towards normal. The exact mechanisms responsible for these alterations are yet to be elucidated. We conclude that serum copper and zinc levels and Cu/Zn ratio are easily measurable biochemical indices that can be used as predictors of successful treatment in pediatric patients with lymphomas.

Potentiation of tamoxifen activity by verapamil in a human breast cancer cell line

The tumor cell growth inhibitory activity of tamoxifen was enhanced significantly by verapamil treatment in an estrogen receptor positive human breast cancer cell line, MCF-7. Treatment of MCF-7 cells with 5 and 10 micrograms/mL verapamil produced a 1.8- and 2.8-fold increase, respectively, in tamoxifen activity. Unlike reversal of multi-drug resistance, the verapamil-mediated increase in tamoxifen activity was not associated with enhanced drug accumulation. Tamoxifen treatment alone or in combination with verapamil did not affect the activity of protein kinase C, an enzyme implicated in the anti-tumor activity of tamoxifen. Addition of 17 beta-estradiol in the cell survival assay system partially abrogated the modulatory effect of verapamil. These data suggest that potentiation of tamoxifen activity by verapamil may involve interaction of this agent with the estrogen receptor. In conclusion, potentiation of tamoxifen activity by calcium channel blockers represents a novel approach for improving the therapeutic results with tamoxifen in women with breast cancer.

Association of single-stranded transferred DNA from Agrobacterium tumefaciens with tobacco cells

During the inception of crown gall tumorigenesis, the transferred DNA (T-DNA) is processed from the Ti (tumor inducing) plasmid of Agrobacterium tumefaciens and is transferred to plant cells. T-DNA processing and transfer require the induction of vir (virulence) genes by phenolic compounds secreted by wounded plant cells. After vir gene induction, both single-stranded (T-strands) and double-stranded forms of processed T-DNA accumulate in the bacteria. Although current models favor the transfer of T-strands to plants, there has yet been no experimental evidence to show this. In this paper, we show that T-strands disappear from acetosyringone-induced A. tumefaciens within 30 min of bacterial cocultivation with tobacco protoplasts. PCR analysis of T-DNA associated with protoplasts indicates that single-stranded, but not double-stranded, T-DNA can be detected in the plant cells within 30 min of bacterial cocultivation. Control experiments show that this T-DNA does not originate from lysed contaminating bacterial cells. T-DNA transfer depends on a functional bacterial virB operon. Protoplast infections using an A. tumefaciens virE mutant result in a low level of accumulation of T-strands in the plant cells.

Modified Levinson's test in rapid diagnosis of tuberculous meningitis

Modified Levinson's precipitation test was done in 64 cases of TBM, 54 cases of TBM with inconsistent CSF finding, and 32 cases of pyogenic meningitis. The test was positive in 93.7% cases of TBM (sensitivity, 93.7%), 85.5% cases of TBM with doubtful diagnosis and in 9.4% cases of pyogenic meningitis (specificity 90.6%) compared to 79.7%, 72.2% and 18.8% in original Levinson's test, respectively. With CSF examination only 66% cases of TBM could be diagnosed while with modified Levinson's test and CSF analysis 89% cases could be diagnosed (p < 0.001). So modified Levinson's test for diagnosis of TBM is better than Levinson's test (p < 0.05) with an added advantage of time saving.

Glutathione-linked detoxification pathway in normal and malignant human bladder tissue

This study compares the levels of glutathione (GSH) and GSH-dependent detoxification enzymes, which have been implicated in anti-cancer drug resistance, in paired normal and malignant human bladder tissues, a tumor with high incidence of inherent drug resistance. Although the mean GSH transferase (GST) activity did not differ significantly in normal and neoplastic bladder tissues, this enzyme activity was relatively higher in tumor tissues of five out of ten patients as compared with corresponding normal tissues. Similarly, the mean GSH content and GSH reductase activity did not differ significantly between normal and neoplastic bladder tissues. On the other hand, the mean GSH peroxidase activity towards cumene hydroperoxide and catalase activity in bladder tumors was higher by about 1.5 and 1.4 times, respectively (P < 0.05), compared with those of normal tissues. GST isoenzymes corresponding to the three major classes (alpha, mu and pi) were expressed in every normal bladder tissue examined in the present study. Overexpression of GST pi was observed in 60% of the bladder tumors, whereas alpha and mu type GST proteins in tumor tissues were lower at frequencies of 62.5% and 37.5%, respectively, compared with the corresponding normal tissues. These results suggest that (a) elevated levels of GSH peroxidase, catalase and GST pi in human bladder tumors may contribute, at least in part, to the intrinsic drug resistance of this neoplasm and (b) anti-oxidative enzymes GSH peroxidase and/or catalase may represent markers for this neoplasia, although a large number of tissue specimens must be analyzed to validate this hypothesis.

Inadequate superoxide production by canine neutrophils in response to the combination of N-formyl-methionyl-leucyl-phenylalanine and cytochalasin B

The formylated peptide, N-formyl-methionyl-leucyl-phenylalanine, at concentration of 0.22 microM, failed to stimulate canine neutrophils to produce adequate amounts of superoxide. Furthermore, addition of cytochalasin B did not augment superoxide generation appreciably.

Mechanism of differential sensitivity of human bladder cancer cells to mitomycin C and its analogue

This study was undertaken to elucidate the mechanism(s) of differential sensitivity of human bladder cancer cell lines J82 and SCaBER to mitomycin C (MMC) and its analogue, BMY 25067. The IC50 values for MMC and BMY 25067 in the SCaBER cell line were respectively 5- and 4-fold higher than in J82. BMY 25282 and BMY 25067 were significantly more cytotoxic, on a molar basis, than MMC in both the cell lines. NADPH cytochrome P450 reductase and DT diaphorase activities were significantly higher in the J82 cell line than in SCaBER, suggesting that relatively lower sensitivity of the SCaBER cell line to MMC and BMY 25067 may be due to deficient drug activation. This conclusion was supported by the observation that IC50 values for BMY 25282, which has lower quinone reduction potential than MMC and BMY 25067, did not differ significantly in these cell lines. A correlation between drug sensitivity, oxyradical formation and levels of antioxidative enzymes was not observed. These results suggest that the relatively lower sensitivity of SCaBER cells to MMC or BMY 25067 may be independent of differential oxyradical formation. MMC-induced DNA interstrand cross-link (ISC) formation was markedly lower in the SCaBER cell line than in J82. However, it remains to be seen if the reduced ISC frequency in the SCaBER cell line is a consequence of deficient drug activation or results from increased repair of the damaged DNA.

Anterior fontanel size

Anterior fontanel size was determined in a cross-sectional study of 445 infants ranging in age from newborn period to 2 years. The mean anterior fontanel size in neonates was 3.37 +/- 0.61 cm which decreased to 0.37 +/- 0.06 cm in 24 months age group. The age of closure of anterior fontanel was 12, 18 and 24 months in 40%, 70.4% and 91.3%, respectively.

Perforated typhoid enteritis in children

A prospective study of 65 patients with perforated typhoid enteritis managed operatively over a 3 year period at a university hospital is presented. There were 45 males and 20 females with ages ranging from 5 to 15 years. Presenting symptoms were fever, abdominal pain, vomiting and either diarrhoea or constipation. All the patients were subjected to surgery and 56 (86%) underwent two-layer bowel closure after freshening of ulcer margins. The overall mortality rate in this study was 20% and was adversely influenced by the increasing duration of perforation, presence of shock and faecal peritonitis. Early surgery after prompt and adequate resuscitation is life saving. However, prevention of typhoid fever by providing safe drinking water and better sanitary conditions appears to offer the best chance of decreasing the high rates of mortality and morbidity of this deadly disease.

Mitomycin C sensitivity in human bladder cancer cells: possible role of glutathione and glutathione transferase in resistance

In this study, we have examined the relationship between sensitivity to mitomycin C (MMC) and glutathione (GSH) and glutathione transferase (GST) levels using a panel of three unrelated human bladder cancer cell lines. J82, HT-1197, and SCaBER. Cell lines HT-1197 and SCaBER were about 2- and 4.5-fold more resistant to MMC as compared to J82. Although the GSH level did not differ significantly in these cell lines, GST activity in HT-1197 and SCaBER cells were higher by about 2.3- and 6.0-fold, respectively, as compared to J82. Similar to GST activity, GST pi content was highest in the most insensitive cell line and lowest in J82 cells. The cytotoxicity of MMC was increased significantly in these cells by a 1-h pretreatment with a nontoxic concentration of ethacrynic acid (EA), an inhibitor of GST activity. EA pretreatment resulted in a marked GSH depletion as well as GST activity inhibition in both of these cells. Although pretreatment of J82 and SCaBER cells with a nontoxic concentration of D,L-buthionine-S,R-sulfoximine (BSO) caused similar GSH depletion, the cytotoxicity of MMC was enhanced only in SCaBER cells. The differential effect of BSO on MMC cytotoxicity in these cell lines appeared to be due to the differences in the extent of GSH regeneration after removal of BSO. While a marked GSH regeneration occurred in J82 cells within 1 h after BSO removal, such an effect was not observed in SCaBER cells. Combined treatment of these cells with BSO and EA produced a greater potentiation of MMC cytotoxicity in both the cell lines when compared to BSO or EA treatment alone. We conclude that GSH/GST levels may affect the sensitivity of human bladder cancer cells to MMC.

Efficacy of prednisone in refractory multiple myeloma and measurement of glucocorticoid receptors. A Southwest Oncology Group study

BACKGROUND

Prednisone is an active drug in the treatment of multiple myeloma. The optimal dose, frequency, and role of glucocorticoid receptors (GR) in response to prednisone is unknown.

PURPOSE

The purposes of this study were (1) to estimate the response rate of alternate-day high dose prednisone in patients with relapsing and refractory multiple myeloma; (2) to measure the rate of GR levels; and (3) to correlate the response of prednisone with GR status.

PATIENTS AND METHODS

Between 8/86 and 1/90, 127 patients were entered onto the study with 121 evaluable for response. The number of GR sites/cell was determined on mononuclear cells isolated from pretreatment bone marrow aspirates using a one point GR binding assay. Patients received prednisone 100 mg po qod x 2 weeks, followed by 50 mg po qod x 10 weeks.

RESULTS

The overall response rate was 10% (95% CI: 5-15%) with a median survival of 11.8 months. The GR sites/cell ranged from 0-53,212 with a mean of 8,371 sites/cells. Stratification of GR sites into 0-2,500, 2,501-6,000 and > 6,000 sites/cells was associated with a response rate of 6%, 27% and 4% respectively (p = 0.009). The median survival of patients in these categories was 8.1, 14.9 and 10.6 months respectively. This was not significant by the logrank test (p = 0.11). Although myeloma patients with intermediate levels of GR sites/cell initially responded more favorably to prednisone, their long-term survival was not significantly improved.

CONCLUSIONS

Alternate-day high-dose prednisone was well tolerated and may provide palliative benefit for a subset of patients with relapsing and refractory multiple myeloma. The survival of patients on this study was comparable to that reported with other but more toxic doses of glucocorticoids.

Structure of the crystalline complex of cytidylic acid (2'-CMP) with ribonuclease at 1.6 Å resolution. Conservation of solvent sites in RNase-A high-resolution structures

The X-ray structure of the inhibitor complex of bovine ribonuclease A with cytidylic acid (2'-CMP) has been determined at 1.6 A resolution and refined by restrained least squares to R = 0.17 for 11 945 reflections. Binding of the inhibitor molecule to the protein is confirmed to be in the productive mode associated with enzyme activity. A study of conserved solvent sites amongst high-resolution structures in the same crystal form reveals a stabilizing water cluster between the N and C termini.

Hearing evaluation in children with bacterial meningitis

Twenty four children with bacterial meningitis were studied prospectively to ascertain the incidence, type and severity of hearing loss. The incidence of sensorineural hearing loss was 20.8%. Patients with hearing loss were followed-up audiologically for six months to find out the progress of hearing impairment. Of the five patients with sensorineural hearing loss only one showed partial recovery while the other three did not show any improvement. Of the five patients with sensorineural hearing loss only one showed partial recovery while the other three did not show any improvement. One patient was lost to follow-up, therefore, recovery was not known. The degree of hearing loss varied form mild to moderate. Antibiotic treatment and laboratory data were analysed to identify the high risk factors predisposing to hearing impairment. The presence of low CSF sugar level, high protein at the initial lumbar puncture and presence of neurological deficits was associated with a significantly higher risk of hearing loss. However, the nature of antibiotic therapy, duration of illness, age and sex of the patients were not significant risk factors in the development of hearing impairment.

Observation of lipid profile and lipoproteins in viral hepatitis and hepatic coma

Lipid profile and lipoprotein levels were estimated in 35 patients of viral hepatitis, 15 patients of viral hepatitis with coma and in age and sex match 35 healthy controls. The values were compared in different groups. Levels of triglycerides were significantly raised (145.00 +/- 30.70 mg/dl) in viral hepatitis as compared to viral hepatitis with coma (111.40 +/- 16.80 mg/dl) which were similar to controls (110.8 +/- 20.6 mg/dl). Patients who recovered had higher levels of triglycerides (136.0 +/- 30.8 mg/dl) as compared to those who expired (110 +/- 15.72 mg/dl). Total serum cholesterol remained statistically unaltered in both groups. HDLc was significantly decreased in both groups, viral hepatitis (2.23 +/- 6.7 mg/dl) and viral hepatitis with coma (16.52 +/- 2.27 mg/dl) in comparison to controls (62.21 +/- 18.04 mg/dl). The levels were much lower in patients with coma than without coma. Furthermore the values were still lower in patients who expired (15.82 +/- 2.27 mg/dl) than in patients who recovered (24.13 +/- 7 mg/dl). The levels of LDLc were significantly raised in both groups, as compared with each other and in relation to mortality. VLDLc levels were significantly decreased in patients of viral hepatitis (22.13 +/- 5.8 mg/dl) as well as on viral hepatitis with coma (21.89 +/- 4.3 mg/dl). However, no significant difference was observed when compared with each other and in relation to mortality. Thus it may be concluded that isolated low value of HDLc in viral hepatitis may be used as a prognostic indicator.

Breastfeeding and childhood cancer

Total duration of breastfeeding and of exclusive breastfeeding was studied and compared in 99 childhood cancer cases and 90 controls. The difference between the average duration of breastfeeding in cases and controls was significant (p < 0.05), but when average duration of exclusive breastfeeding was compared in cases and controls the difference was highly significant (p < 0.001). In lymphoma cases and controls the difference between the average duration of breastfeeding was moderately significant (p < 0.01). However, when average duration of exclusive breastfeeding was compared in lymphoma cases and controls the difference was highly significant (p < 0.001). When other cancer groups and controls were compared with respect to their total duration of breastfeeding and duration of exclusive breastfeeding the differences when insignificant (p > 0.05). Cases and controls were not different with respect to their age, sex, birth year, birth order, age and educational status of mothers, smoking of fathers and socioeconomic status. However, a positive family history of cancer was obtained in 4 (4%) of cases whereas in controls it was obtained in only 1 (1.1%).

Genetic transformation of Brassica nigra by agrobacterium based vector and direct plasmid uptake

Genetic transformation systems have been established for Brassica nigra (cv. IC 257) by using an Agrobacterium binary vector as well as by direct DNA uptake of a plasmid vector. Both the type of vectors carried nptII gene and gus gene. For Agrobacterium mediated transformation, hypocotyl tissue explants were used, and up to 33% of the explants produced calli on selection medium. All of these expressed B-glucuronidase gene on histochemical staining. Protoplasts isolated from hypocotyl tissues of seedlings could be transformed with a plasmid vector by FEG mediated uptake of vector DNA. A number of fertile kanamycin resistant plants were obtained using both the methods, and their transformed nature was confirmed by Southern blot analysis and histochemical staining for GUS. Backcrossed and selfed progenies of these transformed plants showed the presence of npt and gus genes.

Automated perimetric changes following panretinal photocoagulation in diabetic retinopathy

Sixty eyes--30 with severe nonproliferative diabetic retinopathy (NPDR) and 30 with proliferative diabetic retinopathy (PDR)--underwent argon laser panretinal photocoagulation (PRP). Static perimetry (Humphrey automated visual field analyzer 630, Threshold Prog Central 30-1 and Peri 30/60-1) was done 1 day before and 6 weeks after the initial laser treatment. One day before treatment, the fields of the NPDR and PDR eyes differed mainly in the central field affection: the PDR eyes had more localized areas of markedly decreased retinal sensitivity and, therefore, a higher initial mean deviation value and higher corrected pattern standard deviation values. However, peripheral retinal sensitivity was equally depressed in the NPDR and PDR eyes. Six weeks after treatment, central retinal sensitivity had significantly improved in all of the eyes, although more so in the eyes with severe NPDR. This study suggests that static-perimetry-guided PRP is an effective treatment for diabetic retinopathy, especially severe NPDR.