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1.
The structure of the title compound was determined by X-ray analysis. Medicinal compounds with Schiff base structure have been widely synthesized and investigated in recent years. The functional group-CH?N- of the Schiffbases has been shown to have considerable biological importance1) . Many compounds with such a structure have important analgesic, anti-inflammatory, antibiotic, antimicrobial and especi ally anticancer activities2-8). Medicinal sulphonamides, having a primary amino group in their molecule, react very easily with salicylaldehyde or its derivatives9). Information about the exact structure of the reac tion products is rather scanty, however, even though the formation reaction of the base has been utilized in many analytical pr ocedures for medicinal sulphonamides9-12) and many such Schiff bases have been found to possess good bac teriostatic properties13-14).  相似文献   
2.
The colorectum and uterine endometrium are the two most commonly affected organs in hereditary nonpolyposis colon cancer (HNPCC), but the genetic basis of organ selection is poorly understood. As tumorigenesis in HNPCC is driven by deficient DNA mismatch repair (MMR), we compared its typical consequence, instability at microsatellite sequences, in colorectal and endometrial cancers from patients with identical predisposing mutations in the MMR genes MLH1 or MSH2. Analysis of non-coding (BAT25, BAT26, and BAT40) and coding mononucleotide repeats (MSH6, MSH3, MLH3, BAX, IGF2R, TGF beta RII, and PTEN), as well as MLH1- and MSH2-linked dinucleotide repeats (D3S1611 and CA7) revealed significant differences, both quantitative and qualitative, between the two tumor types. Whereas colorectal cancers displayed a predominant pattern consisting of instability at the BAT loci (in 89% of tumors), TGF beta RII (73%), dinucleotide repeats (70%), MSH3 (43%), and BAX (30%), no such single pattern was discernible in endometrial cancers. Instead, the pattern was more heterogeneous and involved a lower proportion of unstable markers per tumor (mean 0.27 for endometrial cancers versus 0.45 for colorectal cancers, P < 0.001) and shorter allelic shifts for BAT markers (average 5.1 bp for unstable endometrial cancers versus 9.3 bp for colorectal cancers, P < 0.001). Among the individual putative "target" loci, PTEN instability was associated with endometrial cancers and TGF beta RII instability with colon cancers. The different instability profiles in endometrial and colorectal cancers despite identical genetic predisposition underlines organ-specific differences that may be important determinants of the HNPCC tumor spectrum.  相似文献   
3.
PTEN on 10q23.3 encodes a dual-specificity phosphatase that negatively regulates the phosphoinositol-3-kinase/Akt pathway and mediates cell-cycle arrest and apoptosis. Germline PTEN mutations cause Cowden syndrome and a range of several different hamartoma-tumor syndromes. Hereditary nonpolyposis colon cancer (HNPCC) syndrome is characterized by germline mutations in the mismatch repair (MMR) genes and by microsatellite instability (MSI) in component tumors. Although both colorectal carcinoma and endometrial carcinoma are the most frequent component cancers in HNPCC, only endometrial cancer has been shown to be a minor component of Cowden syndrome. We have demonstrated that somatic inactivation of PTEN is involved in both sporadic endometrial cancers and HNPCC-related endometrial cancers but with different mutational spectra and different relationships to MSI. In the current study, we sought to determine the relationship of PTEN mutation, 10q23 loss of heterozygosity, PTEN expression, and MSI status in colorectal cancers (CRCs). Among 11 HNPCC CRCs, 32 MSI+ sporadic cancers, and 39 MSI- tumors, loss of heterozygosity at 10q23.3 was found in 0%, 8%, and 19%, respectively. Somatic mutations were found in 18% (2 of 11) of the HNPCC CRCs and 13% (4 of 32) of the MSI+ sporadic tumors, but not in MSI- cancers (P = 0.015). All somatic mutations occurred in the two 6(A) coding mononucleotide tracts in PTEN, suggestive of the etiological role of the deficient MMR. Immunohistochemical analysis revealed 31% (14 of 45) of the HNPCC CRCs and 41% (9 of 22) of the MSI+ sporadic tumors with absent or depressed PTEN expression. Approximately 17% (4 of 23) of the MSI- CRCs had decreased PTEN expression, and no MSI- tumor had complete loss of PTEN expression. Among the five HNPCC or MSI+ sporadic CRCs carrying frameshift somatic mutations with immunohistochemistry data, three had lost all PTEN expression, one showed weak PTEN expression levels, and one had mixed tumor cell populations with weak and moderate expression levels. These results suggest that PTEN frameshift mutations in HNPCC and sporadic MSI+ tumors are a consequence of mismatch repair deficiency. Further, hemizygous deletions in MSI- CRCs lead to loss or reduction of PTEN protein levels and contribute to tumor progression. Finally, our data also suggest that epigenetic inactivation of PTEN, including differential subcellular compartmentalization, occurs in CRCs.  相似文献   
4.
5.
We describe a lethal malformation syndrome in 28 newborn infants from 18 families. The main manifestations were hydrocephalus (often with an unusual structure of the brain and the occipital bone), very small mandible, Polydactyly, congenital heart defect, abnormalities of the respiratory organs, and (different from the Meckel syndrome) normal kidneys. Polyhydramnios and stillbirth or neonatal death were the rule. Autosomal recessive inheritance is evident. This syndrome is another in the group of rare recessive disorders which are found in Finland. Because of the 25 % recurrence risk and possibilities for prenatal diagnosis, this syndrome should be recognized by paediatricians and, because of the frequent stillbirths, also by obstetricians and pathologists. The name hydrolethalus syndrome (hydramnios, hydrocephalus, lethality) may be of help in this.  相似文献   
6.
Most of the effects of estrogens are mediated by estrogen receptors. Vascular endothelial cells and smooth muscle cells express estrogen receptor (ESR1) in both genders. A long genotype group of a common thymine-adenine (TA) dinucleotide repeat polymorphism in the regulatory region of this gene has previously been related to coronary artery disease. The present study examined whether coronary blood flow is affected by this genotype. A total of 49 healthy men were genotyped by PCR and divided into three groups according to median number of the ESR1 promoter TA repeat (=19), i.e., in the short allele genotype group both alleles were of fewer than 19 repeats whereas in the long allele group both alleles were 19 repeats or more. The intermediate group comprised men who had one short and one long allele. Myocardial blood flow was measured by positron emission tomography using [15O]water, performed at rest and during adenosine stimulation. Men with long alleles had lower adenosine-stimulated coronary flow than those with short alleles and those with one short and one long allelle. Our results suggest that adenosine-stimulated myocardial perfusion is lower in subjects with ESR1 long alleles than the other TA repeat genotypes.  相似文献   
7.
The relationship between time and the post-traumatic metabolic response was studied in a commonly used experimental model of trauma. Twenty nine rats underwent laparotomy and jugular vein sham catheterization as the standard trauma. The rats were fed ad libitum and compared to pair fed controls in terms of nitrogen balance and liver protein synthesis. The pairs of rats were divided into three groups according to the duration of the experiment, which was 24 h, 48 h or 72 h. The nitrogen balance was calculated daily and the liver protein synthesis in vitro measured in 10 rats after 48 h with an asanguinous perfusion system using L-(1-C(14))-Leucine. The metabolic effect of trauma was first detected in liver protein synthesis, which was diminished in the early post-traumatic period (percentage synthesis rates: post-traumatic 34.6 +/- 10.7 and pair fed 60.4 +/- 21.3, Mean +/- SD, P < 0.05). During this period the whole body nitrogen balances were similar (post-traumatic -1.200 +/- 1.440 and pair fed -0.880 +/- 1.130, gN/kg/48 h, mean +/- SD). On the third day, the response to nitrogen intake and the nitrogen balance became significantly worse in the post-traumatic rats (post-traumatic 0.214 +/- 1.680 and pair fed 1.236 +/- 1.220, gN/kg/day, mean +/- SD). These observations suggest that, firstly, the 'flow' phase has its onset on the third post-trauma day, and secondly that trauma does decrease liver protein synthesis, and this decrease lasts at least through the 'ebb' phase. The results indicate the necessity of defining the metabolic phase in experimental studies of post-traumatic metabolism.  相似文献   
8.
AIM To compare the effects of regular vs low-FODMAP rye bread on irritable bowel syndrome(IBS) symptoms and to study gastrointestinal conditions with Smart Pill?.METHODS Our aim was to evaluate if rye bread low in FODMAPs would cause reduced hydrogen excretion,lower intraluminal pressure,higher colonic p H,different transit times,and fewer IBS symptoms than regular rye bread.The study was a randomized,double-blind,controlled cross-over meal study.Female IBS patients(n = 7) ate study breads at three consecutive meals during one day.The diet was similar for both study periods except for the FODMAP content of the bread consumed during the study day.Intraluminal p H,transit time,and pressure were measured by Smart Pill,an indigestible motility capsule.RESULTS Hydrogen excretion(a marker of colonic fermentation) expressed as area under the curve(AUC)(0-630 min) was [median(range)] 6300(1785-10800) ppm?min for low-FODMAP rye bread and 10 635(4215-13080) ppm?min for regular bread(P = 0.028).Mean scores of gastrointestinal symptoms showed no statistically significant differences but suggested less flatulence after low-FODMAP bread consumption(P = 0.063).Intraluminal pressure correlated significantly with total symptom score after regular rye bread(ρ = 0.786,P = 0.036) and nearly significantly after lowFODMAP bread consumption(ρ = 0.75,P = 0.052).We found no differences in p H,pressure,or transit times between the breads.Gastric residence of Smart Pill was slower than expected.Smart Pill left the stomach in less than 5 h only during one measurement(out of 14 measurements in total) and therefore did not follow on par with the rye bread bolus.CONCLUSION Low-FODMAP rye bread reduced colonic fermentation vs regular rye bread.No difference was found in median values of intraluminal conditions of the gastrointestinal tract.  相似文献   
9.
OBJECTIVE: The goal of this study was to examine the relationship between plasma asymmetric dimethylarginine (ADMA) level and hyperemic myocardial blood flow (MBF) in subjects with borderline hypertension (BHT) and familial hypercholesterolemia (FH). METHODS: Asymmetric dimethylarginine is an endogenous competitive inhibitor of nitric oxide synthase that may modulate vascular function.We measured plasma ADMA levels and myocardial flow in 77 young men (mean age 35 +/- 5 years), including 47 healthy controls, 16 men with BHT, and 14 men with FH. Basal and dipyridamole-induced myocardial flow was measured using positron emission tomography. Plasma ADMA levels were measured using high-pressure liquid chromatography. RESULTS: Asymmetric dimethylarginine levels were significantly elevated in the BHT group compared with controls (0.59 +/- 0.13 micromol/l vs. 0.43 +/- 0.12 micromol/l, p < 0.001), and they had significantly lower dipyridamole flow (2.85 +/- 1.20 ml/min/g vs. 3.69 +/- 1.68 ml/min/g, p < 0.05). In a multivariate regression model adjusted for the study group, dipyridamole flow was inversely associated with ADMA (p < 0.05), age (p < 0.05), and apolipoprotein B concentration (p < 0.05). CONCLUSIONS: We conclude that plasma ADMA concentration is related to dipyridamole-induced vasodilatory function in young men, independently of blood pressure elevation and hypercholesterolemia. Subjects with BHT have significantly increased plasma ADMA levels, which may partly explain the impaired hyperemic MBF in this condition.  相似文献   
10.
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