Plasma tissue plasminogen activator and plasminogen activator inhibitor-1 levels in acute myocardial infarction

The cause of the circadian variation in the incidence of acute myocardial infarction (AMI) has not been identified. Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) have opposing effects on thrombi. Hence, the extent of the clot, the size of the infarct and outcome of patients could depend on t-PA and PAI-1 levels. In an effort to elucidate the pathophysiologic basis of circadian variation of AMI, we investigated the presence of a possible corresponding circadian variation in the levels of endogenous t-PA and PAI-1 in patients diagnosed to have AMI and the effects of hypertension, diabetes and site of the infarct on these levels. We estimated the levels of t-PA and PAI-1 in platelet-poor plasma of 42 patients with AMI on admission, using the enzyme-linked immunosorbant assay. Although not statistically significant, patients having an AMI in the morning hours had the highest t-PA:PAI-1 ratio. The normal circadian variation in PAI-1 levels was lost in patients with AMI, probably due to the disease process. Also, the t-PA levels in hypertensive patients were significantly lower than in nonhypertensives. PAI-1 levels were also significantly lower in patients with anteroseptal than in inferior and anterolateral AMI. This relationship between the fibrinolytic potential and the site of infarction needs further study. Furthermore, t-PA levels on admission were significantly lower in survivors and may have a predictive value in determining the outcome.     

Circadian variations in the monoamine levels and monoamine oxidase activity in different regions of the rat brain as a function of age

Time-related changes in the levels of norepinephrine (NE), dopamine (DA), 5-hydroxytryptamine (5-HT) and monoamine oxidase (EC 1.4.3.4, MAO) activity have been studied in the cerebral cortex, cerebellum, medulla oblongata, hypothalamus, striatum and midbrain of 21 day, 3, 6, 12 and 24 month old rats maintained at 12 hours of light and 12 hours of dark condition. Maximum NE level was seen during the dark phase in all the regions of 3, 6, 12 and 24 month old rats, whereas in 21 day old, the maximum NE level occurred during the light phase. In the cerebral cortex and in the cerebellum of 21 day old rat DA was absent at all times. In all the other age groups, the maximum DA level was seen during the dark phase, while for 5-HT higher level was during the light phase in all the age groups. MAO activity of 3, 6, 12 and 24 month old rats showed the peak activity at the beginning of the light phase (06:00 hours), whereas cerebral cortex, cerebellum and medulla oblongata of 21 day old rat had its peak MAO activity at 14:00 hours and at 22:00 hours in other regions.     

Herbal/hormonal dietary supplement possibly associated with prostate cancer progression.

BACKGROUND: Patients seek herbal/hormonal dietary supplements (HHDS) to prevent and/or solve health and aging issues. After two men developed an unusual course of clinically aggressive prostate cancer within months of starting daily consumption of the same HHDS product, we investigated the effect of this product on prostate cancer progression. METHODS: We evaluated serum levels of total testosterone, luteinizing hormone, and follicle-stimulating hormone and screened prostate biopsy and metastatic specimens for androgen receptor protein expression and mutations. We did hormone analyses and capillary electrophoresis. We tested the effect of the HHDS product on androgen receptor-negative (DU-145 and PC-3) and androgen receptor-positive (LNCaP) human prostate cancer cell lines. RESULTS: Both patients had low hormone levels. The androgen receptor was expressed in all primary and metastatic prostate cancer tissues and no mutations were identified. Hormone analysis revealed that the HHDS contained testosterone and estradiol. The HHDS product was a more potent dose-dependent stimulator of cancer cell growth than testosterone both in androgen receptor-negative and receptor-positive cell lines. Blocking experiments with increasing concentrations of bicalutamide did not prevent the HHDS product-stimulated growth. We filed an adverse event report with the Food and Drug Administration who issued a warning letter. The manufacturer responded by removing this HHDS product from the market. CONCLUSIONS: The HHDS product contained one or more endocrinologically active tumor-promoting components that had cellular androgen receptor status-independent activity. The HHDS product exhibited potent prostate cancer growth stimulatory activity that was more powerful than that of testosterone, independent of the androgen-receptor status of prostate cancer cells, and resistant to antiandrogen blockade.     

Fast long-distance interactions in the early processing of motion-defined form and of combinations of motion-defined, luminance-defined, and cyclopean form

Humans can compare the orientations and locations of two motion-defined test bars several degrees apart so as to rapidly encode and place in memory their mean orientation, orientation difference, separation and mean location, while ignoring stimuli located between the two test bars. Performance is not impaired by randomly varying the location of the bars. We conclude that the two test bars are not compared by shifting gaze location or attention from one test bar to the other, nor by attending to two spatial locations. In addition, observers can discriminate the orientation difference and mean orientation of two test bars that, each of which is rendered visible by a different sub-modality (motion, disparity or luminance). Taking into account the findings reported here and previously reported findings on the early processing of luminance-defined form (Vis. Res. 40 (2000) 2291, Vis. Res. 42 (2002) 49) and cyclopean form (Proc. Roy. Soc. Lond. B 268 (2001) 213) we propose that the human visual system contains a fast long-distance comparator that compares the orientation and locations of two test bars while being insensitive to stimuli in the space between the test bars, and that this process is independent of whether the test bars are rendered visible by only one of three kinds of contrast (luminance, disparity, motion) or by combinations of the three. One role of this comparator mechanism may be to rapidly bind the spatial aspects of the retinal image across sub-modalities immediately after each saccade.     

Efficient synthesis of the benzo[a]pyrene metabolic adducts of 2'-deoxyguanosine and 2'-deoxyadenosine and their direct incorporation into DNA

A new and efficient method is described for the synthesis in gram quantities of the benzo[a]pyrene (B[a]P) metabolic adducts of 2'-deoxyguanosine (dG) and 2'-deoxyadenosine (dA) substituted, respectively, at the N(2)- and N(6)- positions. When the racemic form of the tris(benzoyloxy)amine 5 (related to the notoriously carcinogenic epoxydiol 2) is coupled with the bromoinosine derivative 6 by means of a Buchwald-Hartwig reaction, the expected pair of diastereomers, 7 and 8, is obtained in high (combined) yield. Selective deblocking of this mixture then gave cleanly the pair of diastereomers 9. These were used in the synthesis of a series of DNA oligomers via their 5'-O-DMT-3'-O-phosphoramidites (10) using standard automated methods. Coupling efficiencies were 94-98% at the point of introduction of the xeno-2'-deoxynucleoside, and in all cases the mixtures of the two diastereomeric oligomers (DMT-off stage) were easily separated by HPLC. By a similar sequence of reactions beginning with 5 and the protected 6-bromopurine 2'-deoxynucleoside 11, it was possible with equal efficiency to introduce the N(6)-modified diastereomers (16) of dA into oligomeric DNA. Circular dichroism measurements were used to establish the fundamental configurations at the xeno-2'-deoxynucleoside site for each of the oligomers. Mass spectral data in both the dG and the dA series confirmed the presence of the xeno-2'-deoxynucleoside in the oligomers. This was complemented by enzymatic degradation of one of the oligomers from each of the series. In both of these cases, after HPLC separation, circular dichroism measurements on the reisolated xenonucleoside also confirmed its presence in the oligomer.     

Quantitative determination of aristolochic acid-derived DNA adducts in rats using 32P-postlabeling/polyacrylamide gel electrophoresis analysis.

Aristolochic acids (AA) are nephrotoxic and carcinogenic nitroaromatic compounds produced by the Aristolochiaceae family of plants. Ingestion of these phytotoxins by humans results in a syndrome known as AA nephropathy, characterized by renal tubulointerstitial fibrosis and upper urothelial cancer. After activation by cellular enzymes, AA I and II react with DNA to form covalent adducts and as such represent potential biomarkers for studies of AA toxicity. Using site-specifically modified oligodeoxynucleotides as standards, we have developed a method for quantifying 7-(deoxyadenosin-N(6)-yl) aristolactam-DNA or 7-(deoxyguanosin-N(2)-yl) aristolactam-DNA adducts in tissues of Wistar rats using an assay in which (32)P-postlabeling techniques are coupled with nondenaturing polyacrylamide gel electrophoresis. The limit of detection with this technique is five adducts in 10(9) nucleotides for a 5-microg DNA sample. In contrast to previous reports, we find that the levels of AA adducts in renal tissues of Wistar rats treated p.o. with AA for 1 week with 5 mg/kg/day of AA I or AA II were much higher than that in the forestomach. Highest adduct levels were observed in rats treated with AA II, suggesting that this compound may be more genotoxic than AA I. Treatment of rats with aristolactam I, an end-product of AA I metabolism, resulted in a much lower level of adduction. This study establishes the feasibility of using AA-DNA adducts as intermediate biomarkers of exposure in studies of AA nephropathy and its associated urothelial cancer.     

Childhood systemic lupus erythematosus in South India

Out of 330 adult Systemic Lupus Erythematosus (SLE) cases who attended the Rheumatic Care Centre, Government General Hospital, 59 children were analysed. There was no case with onset before the age of 5 years. There were 49 females and 110 males (M:F =1∶4.9). The initial manifestations were fever (67%), arthritis (61%), skin rash (59%) and lymphadenopathy (27.1%). There was no case of Raynaud's phenomenon. Only 10.1% of patients presented with thrombocytopenic purpura. In the cumulative clinical features, arthritis in 86.6%, fever in 79.8%, skin rash in 69.4%, lymphadenopathy in 61% and hepatosplenomegaly in 39.9% were observed. Renal involvement was seen in 49.1%, neuropsychiatric manifestations in 27.1%, pleuropulmonary in 22% and cardiac manifestations in 10.2%. Anaemia was seen in 50.8%, leukopenia in 18.4%, thrombocytopenia in 11.8%, ANA in 100%, anti-dsDNA in 92.3%, anti-Sm in 34.7%, anti-SSA in 38.5%, anti-SSB in 15.4%, ACL in 30.8%, low C3 in 50% and false positive VDRL in 3.3%. Death occurred in 8 children, 3 due to infection, 2 due to renal causes, I due to cardiac and 2 due to central nervous system involvement.     

ENPP1/PC-1 K121Q polymorphism and genetic susceptibility to type 2 diabetes

Genetic susceptibility modulates the impact of obesity on risk for type 2 diabetes. The present study evaluates the role of ENPP1 K121Q polymorphism in prediction of type 2 diabetes in three populations that differ in susceptibility to diabetes and environmental exposure. The three cohorts included 679 nonmigrant South Asians living in Chennai, India (223 with type 2 diabetes); 1,083 migrant South Asians living in Dallas, Texas (121 with type 2 diabetes); and 858 nonmigrant Caucasians living in Dallas, Texas (141 with type 2 diabetes). Patients with type 2 diabetes were included in these cohorts if they had diabetes onset before the age of 60 years. The prevalence of subjects carrying the polymorphic ENPP1 121Q allele was 25% in the nondiabetic group and 34% in the diabetic group of South Asians living in Chennai (P = 0.01). The prevalence in the nondiabetic and diabetic groups were 33 and 45% (P = 0.01) for the South Asians living in Dallas and 26 and 39% (P = 0.003) for the Caucasians. Although further replication studies are necessary to test the validity of the described genotype-phenotype relationship, our study supports the hypothesis that ENPP1 121Q predicts genetic susceptibility to type 2 diabetes in both South Asians and Caucasians.     

Sclerosing stromal tumour of the ovary--a clinicopathologic spectrum

Majority of the Sclerosing stromal tumours of the ovary documented in the literature are single case reports. We report a series of 4 cases. Among the 4 cases encountered the mean age at presentation was 22.2 years. The clinical presentation varied from asymptomatic mass per abdomen (2 cases), menorrhagia (1 case) and amenorrhoea (1 case). The tumour was unilateral in all the cases with an average size of 10 cms. Grossly the appearances varied from a solid, partly cystic, edematous tumour (2 cases) to solid,firm tumour with yellow flecks (1 case) to unilocular cystic tumour (1 case). Microscopically, the tumour was characterized by cellular pseudolobules composed of a disorderly admixture of collagen-producing fibroblasts and lipid rich lutein cells with shrunken nuclei. In one case the lutein cells had a robust appearance with abundant cytoplasm and vesicular nuclei. The pseudolobules were very vascular and separated by hypocellular dense to oedematous fibrous tissue. Frozen section demonstrated fat in luteinized cells in 3 cases.     

Physical status of newborns and neonatal outcome

OBJECTIVE: To determine the extent to which physical status at birth is associated with neonatal mortality and the causes of mortality vis-a-vis size at birth and gestational age. METHOD: 11,223 consecutive live births completing 26 weeks of gestation and weighing > or = 500 gm were included in the study. Birth weight and chest circumference were recorded as per WHO guidelines. Gestational age was calculated on the basis of L.M.P. and the new Ballard's score. Deaths occurring in the hospital within 28 days were recorded. Percentile values of gestational age specific birth weights were calculated separately for singletons and multiple births. Percentage of SGA was calculated with reference to WHO recommended values. Birth weight-gestational age-specific mortality rates were calculated at 2 wk and 500 gm intervals. RESULT: Low-birth-weight babies constituted 39.8% of the total, much in excess of WHO recommended figure of 15%. 76% deaths occurred among LBW babies and 56.2% among preterms. Mortality showed remarkable decline as the birth weight increased to 2,000 gm. The lowest mortality was among singletons weighing 2,500-3,000 gm and of 38-40 weeks gestation. Prevalence of SGA at 40 and 42 weeks were 73.7% and 83.6% respectively. But, if SGA babies not categorised as LBW were excluded, the values came down to 32% and 36% respectively. 36% of all deaths occurred during the first 24 hrs of birth; asphyxia and related causes contributing to 50% of it. CONCLUSION: Cut-off value of 2,000 gm instead of 2,500 gm for birth weight may be preferable in countries where most LBW babies are SGAs. Simultaneously, deaths in non-LBW babies due to perinatal causes contribute sgnificantly to total neonatal mortality and need due attention through sensitising obstetricians in essential newbom care and timely Intervention.