Studies on energetic compounds. 25. An overview of preparation, thermolysis and applications of the salts of 5-nitro-2,4-dihydro-3H-1,2,4-triazol-3-one (NTO).

The research work reported on the preparation, characterisation and applications of more than 50 salts of NTO has been reviewed thoroughly. A broad classification and sub classification of all these compounds has been given on the basis of nature of the compounds with which NTO forms salts. Attempt has been made to discuss the structure of these salts by summarising analytical data reported from 13C NMR. The structure as determined by IR spectroscopy as well as XRD has also been discussed briefly. A generalised mechanism for the thermolysis of the metal salts has also been given and any deviation from this has been narrated in particular cases. The kinetic details, thermodynamical and thermochemical data as well as performance parameters have also been reviewed. Thus, the futuristic potentials of these salts are analysed critically and further studies have been suggested.     

Is there a correlation in breast carcinomas between tumor size and number of tumor vessels detected by gadolinium-enhanced magnetic resonance mammography?

Tumor vessels are known as a sign of malignancy in breast tumors. Is there a correlation between tumor size and the number of vessels in cases of breast tumor examined by dynamic gadolinium (Gd)-enhanced MR imaging? Eighteen patients (mean age, 46±7 years) underwent dynamic Gd-enhanced MR imaging of the breast by three-dimensional gradient echo sequence using thin-layer technique (2.5 mm) at 1.5T. The dynamic study included one precontrast and four postcontrast sequences (every 90 seconds) in coronal slices. Postprocessing by subtraction method and reconstruction in both transverse and sagittal planes were performed. All carcinomas showed rapid Gd enhancement. Tumor size (0.5 to 31.5 cm³; mean, 6.3±3.7 cm³) and number of vessels (1 to 10; mean, 3±2.1) were detected in summation of all three directions. A significant correlation was found between number of vessels and tumor size (r=0.787,p≤0.01). Breast tumor size significantly correlated with the number of vessels detected by Gd-enhanced MR mammography. The introduced method is a further important step in differentiating a carcinoma from a benign lesion.     

Direct visualization of thymocyte apoptosis in neglect, acute and steady-state negative selection

During thymocyte differentiation, the majority of the developing cells die in situ by apoptosis and are subsequently removed by macrophages. DNA fragmentation is one of the hallmarks of apoptosis and can be detected in situ by TdT-mediated dUTP-biotin nick end labeling (TUNEL). We used TUNEL combined with immunohistology to determine the sites of thymocyte apoptosis in mice transgenic for a TCR (F5) which recognizes a peptide (NP68) of the influenza virus nucleoprotein (NP) presented on the MHC class I H-2Db molecule. Apoptosis due to neglect was studied in F5 mice expressing a neutral MHC haplotype (F5/H-2q) and in beta 2-microglobulin-deficient F5 mice (F5/ beta 2m+). In both cases, the frequency of apoptotic cells was similar to that seen in F5/H-2b mice and non-transgenic C57BI/10 mice. Antigen-induced apoptosis was studied in F5 mice after i.p. Injection of the cognate NP68 peptide and in F5/NP double-transgenic mice. Three hours after peptide injection, apoptosis was high throughout the thymus cortex and clusters of apoptotic cells formed due to tissue macrophage uptake, whereas the thymic medulla remained unaffected. Massive recruitment of inflammatory cells into the thymus was seen as early as 1 h after peptide injection. Nine hours after peptide injection changes were apparent in the cortical epithelium and, by 4 days, the cortical network had collapsed to give scattered, compacted epithelial cells. In contrast, in F5/NP double-transgenic mice, thymocyte apoptosis induced by cognate self-peptide was localized at the cortico-medullary junction with little change seen in the epithelium of the cortex.     

MLL genomic breakpoint distribution within the breakpoint cluster region in de novo leukemia in children

OBJECTIVE: This study was performed to determine the effects of environmental stress on the leakage to albumin and architecture of microvessels in the rat mesentery. METHODS: One group of rats (Group A, n = 6) were examined immediately upon arrival at the animal care facility. Groups B (n = 24) and C (n = 32) were housed in rooms with high and low personnel activity, respectively, for up to 7 weeks. Group D (n = 18) was housed in the high activity room for 2, 3, or 4 weeks followed by the low activity room. RESULTS: Rats in the low activity room for 3-4 weeks showed robust microvascular networks within 25% to 50% of the mesenteric windows (each window consisting of the tissue extending between two adjacent feeding arterioles in the mesentery), whereas rats in Group B only showed fragile vessels at the edges of the mesenteric windows within fat deposits. Groups A and C demonstrated little mesenteric fat and few fragile vessels, in contrast to group B. Group D showed increased mesenteric networks and decreased mesenteric fat as recovery progressed. The microvascular networks of 6 rats, randomly selected from Group C, showed few venular leaks following perfusion with fluorescein isothiocyanate-labeled bovine serum albumin (FITC-BSA). Such leaks were abundant in the mesenteric microvasculature of 3 rats randomly selected from Group B. CONCLUSIONS: This study demonstrates that environmentally induced stress alters the architecture and leakage to albumin of the rat mesenteric microvasculature, and emphasizes the importance of closely monitoring the environment of experimental animals.     

Prenatal estrogens and the development of homosexual orientation.

In psychobiological research on sexual orientation, the prenatal hormone theory has a central position. This article examines the hypothesis that prenatal estrogens contribute to the development of human sexual orientation. Several groups of women with a history of prenatal exposure to diethylstilbestrol (DES), a nonsteroidal synthetic estrogen, were compared with several samples of control women in the context of a comprehensive study of the psychiatric and psychologic effects of prenatal DES. Various aspects of sexual orientation were assessed by systematic interview. Consistently across samples, more DES-exposed women than controls were rated as bisexual or homosexual (scores 2–6 on Kinsey-format scales ranging from 0 to 6). The data are compatible with the hypothesis that prenatal estrogens may play a role in the development of human sexual orientation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Thermal dehydrochlorination of PVC in the presence of rubber seed oil

Dehydrochlorination rates of PVC in nitrogen atmosphere were determined in the presence of rubber seed oil (RSO), epoxidized rubber seed oil (ERSO), barium soap of rubber seed oil fatty acids and barium soap of epoxidized fatty acid of rubber seed oil. The initial rates of dehydrochlorination and the time required for the degradation to attain 1% conversion showed that the rubber seed oil derivatives exert a stabilizing effect on the degradation of PVC. The order of the stabilizing effect was found to be metal soaps of ERSO < metal soaps of RSO < ERSO < RSO.     

Safety and use of gadobutrol in patients with brain tumors (phase III trial)

PURPOSE: The purpose of the study was to investigate the use and safety of Gadobutrol, a new low-osmolar, non-ionic contrast agent for MRI using a total dose of 0.3 mmol/kg b.w. on the basis of a clinical phase 3 study. METHODS: 30 patients with primary brain tumours (n = 15) or cerebral metastases (n = 15) were examined via MRI before and after application of a total of 0.3 mmol/kg b.w. given in two fractions (0.1 and 0.2 mmol/kg b.w.). T2-weighted images were performed before, T1-weighted images before, between and after application of contrast material. RESULTS: In this study one-molar Gadobutrol showed a good tolerance. In half of the cases the contrast between lesion and brain was improved comparing single and triple dose, but this means only a slightly improvement of information for the primary brain tumours compared with single dose. The detected metastatic lesions increased in 40% of the patients after the single dose and in 53% of the patients after cumulative triple dose. There was a consecutive change in therapy in 20% of the patients. CONCLUSION: For the differentiation of primary brain tumours the single dose was sufficient, in metastatic lesions triple dose was essential for the detection or exclusion of multifocality.     

Cure of Helicobacter pylori infection and duration of remission of low-grade gastric mucosa-associated lymphoid tissue lymphoma

BACKGROUND: Low-grade B-cell lymphomas arising in mucosa-associated lymphoid tissue (MALT) are most frequently localized in the gastrointestinal tract. More than 90% of gastric MALT lymphomas are diagnosed in patients with chronic, Helicobacter pylori-associated gastritis. High remission rates for these lymphomas have been observed after the cure of H. pylori infection. Data are lacking, however, with regard to the duration of the remissions. To address this question of remission duration, we have followed 50 patients in whom H. pylori infections were eradicated, and we determined whether the patients in complete remission displayed evidence of residual monoclonal B cells during follow-up. METHODS: Patients were treated with amoxycillin and omeprazole for 2 weeks in an attempt to cure H. pylori infections. Follow-up included endoscopic investigations with biopsy sampling. Monoclonal B cells in biopsy specimens were detected by means of a polymerase chain reaction (PCR)-based assay. RESULTS: H. pylori infections were cured in all 50 patients. The median follow-up for the 50 patients is currently 24 months (729 days; range, 135-1411 days). Forty patients achieved complete remission of their lymphomas, but five have subsequently relapsed. The median time of continuous complete remission for the 40 patients was 15.4 months (468 days; range, 0-1198 days). Among six patients whose Iymphomas did not respond to H. pylori eradication, four revealed high-grade lymphomas upon surgery. PCR indicated the presence of monoclonal B cells during follow-up in 22 of 31 assessable patients in complete remission. CONCLUSIONS: Complete remissions of low-grade gastric MALT Iymphomas after the cure of H. pylori infection appear to be stable, although most patients display evidence of monoclonal B cells during follow-up. Whether these patients are truly cured of their Iymphomas remains to be determined.     

An event-related potential study of age-related changes in sensitivity to stimulus deviance

The mismatch negativity (MMN) of the event-related (brain) potential (ERP) has been shown to reflect the storage of information in sensory memory and is thought to reflect the operation of a mechanism that compares frequently occurring standard with infrequently occurring deviant acoustic events. The MMN was recorded from young (mean = 23 years) and elderly (mean = 72 years) adults to small (50 Hz) and large (300 Hz) frequency deviants and to a variety of novel, environmental sounds. At each level of deviance, MMN amplitude was smaller in the ERPs of older relative to younger adults. Young, but not older adults showed robust MMNs at the smallest level of deviance. Moreover, a P3 component was observed in the ERPs of the young to both large tonal and novel deviants, whereas a robust P3 component was evident only to the novel deviants in the ERPs of the old. The data suggest that older adults demonstrate less sensitivity to stimulus deviance and that only highly deviant events are likely to involuntarily capture their attention.