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Peutz-Jeghers syndrome is characterized by multiple polyps throughout the gastrointestinal tract in association with mucocutaneous pigmentation. Although Peutz-Jeghers syndrome polyps are hamartomas, frequent association of this syndrome with both gastrointestinal and non-gastrointestinal tumours had led to reassessment of the cancer risk in this hereditary disorder. The most common gynaecological tumors in this syndrome are adenoma malignum of the uterine cervix and ovarian sex cord tumor, particularly sex cord tumor with annular tubules. The question of malignant change in a polyp or of the association of gastro intestinal carcinomas still discuss. The authors report a case of Peutz-Jeghers syndrome in a young patient who developed a colonic adenocarcinoma in a hamartomatous polyp together with an incidentally discovered bilateral malignant sex cord tumours. We discuss its association with certain benign and malignant tumors and the risk of rare complications of these hamartomatous polyps. Although malignant tumors are increasingly reported in association with the Peutz-Jeghers syndrome, to our knowledge, there have been no previous reports of such an association in the literature.  相似文献   
3.
In the present work, nearly the entire 16S rRNA gene sequences of 46 clinical samples of Neisseria spp. were determined, and the aligned sequences were analyzed to investigate the diversity of 16S rRNA genes in each commensal Neisseria species. Two 16S rRNA types were identified in two Neisseria sicca strains, three 16S rRNA types in five Neisseria macacae strains, fourteen 16S rRNA types in twenty Neisseria flavescens isolates, and fourteen 16S rRNA types in nineteen Neisseria mucosa isolates. The number of nucleotides that were different between 16S rRNA sequences within specie ranged from 1 to 15. We found high intraspecific sequence variation in 16S rRNA genes of Neisseria spp. strains.  相似文献   
4.

Background

Seaweed polysaccharides are highly active natural substances having valuable applications. The present study was conducted to characterize the physico-chemical properties of sulphated polysaccharides from three Mediterranean brown seaweeds (Cystoseira sedoides, Cystoseira compressa and Cystoseira crinita) and to evaluate their anti-radical, anti-inflammatory and gastroprotective activities.

Methods

The different rates of neutral sugars, uronic acids, L-fucose and sulphate content were determined by colorimetric techniques. The different macromolecular characteristics of isolated fucoidans were identified by size exclusion chromatography equipped with a triple detection: multiangle light scattering, viscometer and differential refractive index detectors, (SEC/MALS/VD/DRI). Anti-inflammatory activity was evaluated, using the carrageenan-induced rat paw edema test in comparison to the references drugs Acetylsalicylate of Lysine and Diclofenac. The gastroprotective activity was determined using HCl/EtOH induced gastric ulcers in rats and to examine the antioxidant effect of fucoidans in the three species, the free radical scavenging activity was determined using 1,1-diphenyl-2-picrylhydrazyl.

Results

The pharmacological evaluation of the isolated fucoidans for their anti-inflammatory, and their gastroprotective effect established that these products from C. sedoides, C. compressa and C. crinita exhibited a significant anti-inflammatory activity at a dose of 50 mg/kg, i.p; the percentages of inhibition of the oedema were 51%, 57% and 58% respectively. And, at the same dose, these fucoidans from C. sedoides and C. compressa showed a significant decrease of the intensity of gastric mucosal damages compared to a control group by 68%, whereas, the fucoidan from C. crinita produced a less gastroprotective effect. Furthermore, the isolated fucoidans exhibited a radical scavenging activity.

Conclusion

The comparative study of fucoidans isolated from three species of the genus Cystoseira showed that they have similar chemicals properties and relatives anti-radical, anti-inflammatory and gastroprotective activities which are found to be promising.  相似文献   
5.
Periprosthetic regurgitation (PPR) is a common complication of mitral valve replacement (MVR). The management of moderate and minor PPR remains controversial. The goal of this prospective study was to determine the incidence, predictors and outcome of PPR discovered using omniplan transoesophageal echocardiography (TEE) performed at the early postoperative period (14.7 days) of MVR with SJM prosthesis. Our study enrolled 56 patients, the mean age was 44.5 +/- 11.9 years. The incidence of PPR was 59% (33 patients). TEE showed one jet in nine patients (27%), two jets in 23 patients (70%) and three jets in one patient (3%). PPR is minor in 24 patients (63%) and moderate in nine patients (27%). No patient developed hemolytic anemia or congestive heart failure. In univariate analysis, diameter of prostheses > 27 mm, number of suture knots < 17 and diameter of prostheses/number of knot ratio > 1.7 independently predicted the presence of PPR. In multivariate analysis only a rapport diameter of protheses/number of suture knots > 1.7 mm is predictif of PPR (odd ratio = 9, P = 0.036). Ninety percent of PPR remained present at six weeks and only 29% were present after 12.5 months. CONCLUSION: Mild and minor PPR were frequent during the early postoperative period after MVR. The clinical significance and natural history is benign and they do not require any specific treatment.  相似文献   
6.
A series of new fluoroquinolone conjugates 8a–g and 9a–f were synthesized via benzotriazole‐mediated synthetic approach with good yield and purity. Some of the synthesized analogs exhibited significant antibacterial properties against Escherichia coli and Staphylococcus aureus with potency higher than that of the parent drugs through in vitro standard bioassay procedure (conjugates 8c and 8d reveal antimicrobial properties with potency 1.9, 61.9, 20.7 and 2.4, 37.1, 8.3 folds relative to the parent antibiotic 6 against E. coli, S. aureus, and Enterococcus faecalis, respectively). The observed experimental data were supported by enzymatic DNA gyrase inhibitory property. Developed BMLR‐QSAR model validates the observed experimental data and recognizes the parameters responsible for the enhanced antibacterial properties.  相似文献   
7.
Journal of Neurology - STUB1 has been first associated with autosomal recessive (SCAR16, MIM# 615768) and later with dominant forms of ataxia (SCA48, MIM# 618093). Pathogenic variations in STUB1...  相似文献   
8.
9.

Introduction

Cavernous hemangiomas of the skull are very infrequent lesions. They arise from intrinsic vasculature of skull bones and manifest at the fourth to fifth decades of life. Calvarial cavernomas are very rare among lesions of the skull. These lesions are usually focal and confined to one calvarial bone.

Discussion

In this report, we are describing a child with diffuse calvarial cavernoma, a very rare lesion with distinctive clinical and radiological manifestations. This is the first case of such morphology described in the literature.  相似文献   
10.
We report the synthesis of new anti-inflammatory 1,7-dihydropyrazolo[3′,4′:4,5]pyrimido[1,6-a]pyrimidine 5 from aminocyanopyrazole. All compounds were characterized by physical, chemical and spectral studies. Preliminary pharmacological evaluation of the resulting products showed that compounds 5a, b, f (50–100 mg/kg, i.p) are active anti-inflammatory agents in carrageenan-induced rat paw oedema assay, and their effects are comparable to that of acetylsalicylic–lysine (300 mg/kg, i.p.), used as a reference drug. The nature of substituent (Y, R3) had a pronounced effect on the anti-inflammatory activity. Studies of structure–activity relationships have led to selection of compound ethyl-3,5-dimethyl-7-imino-N 1-phenyl-1,7-dihydropyrazolo[3′,4′:4,5]pyrimido[1,6-a]pyrimidine-6-carboxylate, 5f which exhibited the most potent anti-inflammatory activity. In addition, the compounds 5a, b, f showed a significant gastroprotective effect against HCl/EtOH-induced gastric ulcer.  相似文献   
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