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21.
Association of IL-8 (-251)T/A polymorphism with susceptibility to and aggressiveness of nasopharyngeal carcinoma 总被引:2,自引:0,他引:2
Ben Nasr H Chahed K Mestiri S Bouaouina N Snoussi K Chouchane L 《Human immunology》2007,68(9):761-769
Interleukin-8 (IL-8) is an angiogenic chemokine that plays a potent role in both development and progression of many human malignancies including nasopharyngeal carcinoma (NPC). In the present study, we evaluated the susceptibility and prognostic implications of the (-251) T/A genetic variation in IL-8 in NPC. We used the allele-specific polymerase chain reaction to characterize the variation of the IL-8 promoter region for 160 unrelated Tunisian patients with NPC and 169 healthy control subjects. There was a significant association between the homozygotes IL-8 (-251) AA genotype and nasopharyngeal carcinoma (OR = 2.46; P = 0.004). The presence of the IL-8 (-251) AA genotype was highly associated with elevated NPC risk for male patients. A significant association was demonstrated between the IL-8 (-251) AA genotype and the aggressive forms of NPC as defined by large tumor size, lymph node metastasis, and advanced stages. Moreover, the presence of the IL-8 (-251) AA genotype indicated a significant association with decreased overall survival. Our findings suggest that the IL-8 promoter polymorphism is associated with increased nasopharyngeal carcinoma risk, particularly in males, as well as disease progress, supporting our hypothesis for IL-8 involvement in NPC pathogenesis. 相似文献
22.
Hassen E Farhat K Gabbouj S Jalbout M Bouaouina N Chouchane L 《Cancer Genetics and Cytogenetics》2007,175(1):41-46
To find out whether polymorphisms 333-Ile/Val and 637-Asp/Gly of the transporter part of the antigen processing 1 gene (TAP1) are associated with the development of nasopharyngeal carcinoma (NPC), we studied a total of 374 subjects (209 patients and 165 controls). We used the amplification refractory mutation system polymerase chain reaction (ARMS-PCR) method for analyzing the TAP1 gene polymorphisms. We found a significant difference between the patients and the controls in both the TAP1 codon 333 and codon 637 (P = 0.009 and P = 0.002, respectively). We also found that genotypes with the A allele were present in 206 patients with NPC and 155 controls (98.5 vs. 93.9%; P = 0.032; OR = 4.43) and that genotypes with the B allele were more often present in the control group (45 vs. 32%; P = 0.004; OR = 0.48), suggesting a significant positive association of the A allele with NPC risk and a protective role of the B allele. We have observed an association between the distribution of TAP1 alleles and the NPC patient's age at onset, compared with controls. These results back up the fact that the etiology of NPC in intermediate-risk countries is completely different in each peak of age prevalence and that each peak may possess its own particular oncogenic mechanism. 相似文献
23.
Md Jasim Uddin Sumedha Liyanage Noureddine Abidi Harvinder Singh Gill 《Journal of pharmaceutical sciences》2018,107(12):3047-3059
Allergen-free pollen shells obtained from natural pollen grains have recently attracted attention as microcapsules for oral therapeutic delivery. We have recently developed a chemical treatment method that enables successful retrieval of hollow pollen shells from diverse species. A comprehensive characterization is critical to characterize the effects of chemical treatment which will not only benchmark the pollen treatment process but can also lay the foundation of quality control procedures to check allergen-removal efficiency during pollen treatment. Therefore, in this study, we followed the effects of chemical treatment on 4 different pollen species using electron microscopy, elemental analysis, gel electrophoresis, confocal microscopy, Fourier-transform infrared spectroscopy, and thermogravimetric analysis. These analyses revealed that acetone treatment removed lipids from the pollen surface. Phosphoric acid treatment removed proteins and nucleic acids from the pollen core and transformed esters into carboxylic acids. Potassium hydroxide hydrolysis changed carbohydrate composition of the pollen wall. Chemically treated pollen shells exhibited hydroxyl and carboxyl functional groups on their surface. Overall, we propose that confocal microscopy could be used as a rapid scanning technique to visualize the removal of biomolecules, whereas Fourier-transform infrared combined with gel electrophoresis could be used as a more objective approach for analysis and benchmarking. 相似文献
24.
Gandham Lakshminarayana Youssef Elmahroug Ashok Kumar Huseyin Ozan Tekin Najeh Rekik Mengge Dong Dong-Eun Lee Jonghun Yoon Taejoon Park 《Materials》2021,14(9)
For both the B2O3-Bi2O3-CaO and B2O3-Bi2O3-SrO glass systems, γ-ray and neutron attenuation qualities were evaluated. Utilizing the Phy-X/PSD program, within the 0.015–15 MeV energy range, linear attenuation coefficients (µ) and mass attenuation coefficients (μ/ρ) were calculated, and the attained μ/ρ quantities match well with respective simulation results computed by MCNPX, Geant4, and Penelope codes. Instead of B2O3/CaO or B2O3/SrO, the Bi2O3 addition causes improved γ-ray shielding competence, i.e., rise in effective atomic number (Zeff) and a fall in half-value layer (HVL), tenth-value layer (TVL), and mean free path (MFP). Exposure buildup factors (EBFs) and energy absorption buildup factors (EABFs) were derived using a geometric progression (G–P) fitting approach at 1–40 mfp penetration depths (PDs), within the 0.015–15 MeV range. Computed radiation protection efficiency (RPE) values confirm their excellent capacity for lower energy photons shielding. Comparably greater density (7.59 g/cm3), larger μ, μ/ρ, Zeff, equivalent atomic number (Zeq), and RPE, with the lowest HVL, TVL, MFP, EBFs, and EABFs derived for 30B2O3-60Bi2O3-10SrO (mol%) glass suggest it as an excellent γ-ray attenuator. Additionally, 30B2O3-60Bi2O3-10SrO (mol%) glass holds a commensurably bigger macroscopic removal cross-section for fast neutrons (ΣR) (=0.1199 cm−1), obtained by applying Phy-X/PSD for fast neutrons shielding, owing to the presence of larger wt% of ‘Bi’ (80.6813 wt%) and moderate ‘B’ (2.0869 wt%) elements in it. 70B2O3-5Bi2O3-25CaO (mol%) sample (B: 17.5887 wt%, Bi: 24.2855 wt%, Ca: 11.6436 wt%, and O: 46.4821 wt%) shows high potentiality for thermal or slow neutrons and intermediate energy neutrons capture or absorption due to comprised high wt% of ‘B’ element in it. 相似文献
25.
Rebai R Rekik N Boudawara MZ Khannous M Bahloul K Chaari S Abid M Ben Mansour H 《Annales d'endocrinologie》2002,63(3):226-230
A 34-year-old woman was hospitalized for exploration of amenorrhea and galactorrhea. She had experienced primary sterility, diagnosed 11 years earlier. Endocrine tests demonstrated hyperprolactinemia (serum prolactin 594 ng/ml). Magnetic resonance imaging (MRI) showed a soft tissue mass located within the posterior part of the sphenoidal sinus. The pituitary gland appeared normal. Medical treatment with bromocriptine was unsuccessful. Transsphenoidal tumor resection was performed. Histology reported adenoma, which was consistent with prolactin-producing tumor demonstrated by immunohistochemical staining for prolactin. Because of the persistence of hyperprolactinemia related to an intra-sphenoidal tumor remnant, bromocriptine (15 mg/d) was initiated. Menses ensued and prolactin level declined (49 ng/ml). One year later, the tumor remnant had disappeared on the MRI and the patient became pregnant. Ectopic adenomas of the sphenoidal sinus are of particular interest due to the diagnostic difficulties encountered. Nevertheless, the nature of the lesion can be determined from the endocrine manifestations. Some of these tumors respond to medical treatment, similar to intra sellar tumors. Surgery remains however the only means of obtaining definitive diagnosis and cure. 相似文献
26.
Mariem Rekik Khadija Sellami Fatma Hammami Massara Baklouti Hamida Turki 《Clinical Case Reports》2022,10(4)
Seborrheic keratosis is a common benign epidermal tumor occurring in patients aged over 50 years. It is located preferentially in the trunk, head and neck. The genital location is rare. We report a case of 59 year‐old‐men presenting a seborrheic keratosis of the pubis. 相似文献
27.
28.
Akhaddar A Jiddane M Chakir N El Hassani R Moustarchid B Bellakhdar F 《Surgical neurology》2002,58(3-4):266-270
BACKGROUND: Hydrocephalus and cerebellar abscesses as the principal manifestations of posterior fossa dermoid cyst are rare. In addition, extradural dermoid cyst of the posterior fossa has been described in only 9 cases in the literature. We present an unusual case of obstructive hydrocephalus due to cerebellar abscesses induced by an adjacent extradural dermoid cyst with complete occipital dermal sinus. CASE DESCRIPTION: A 14-month-old child presented with acute raised intracranially pressure, seizures, and meningitis. Neuroradiological studies revealed cerebellar cysts with ring enhancement associated with a contiguous occipital cyst, with compression of the adjacent cisterns and the fourth ventricle causing hydrocephalus. The diagnosis of cerebellar abscesses with congenital occipital defect was briefly entertained. The patient was treated by radical excision of the occipital cyst with hair contents, the dermal sinus, and the abscesses through a suboccipital approach, followed by systemic antibiotic therapy with a good outcome. Pathologic examination revealed a dermoid cyst. CONCLUSION: Posterior fossa dermoid cyst should be considered in all children with occipital skin lesions, especially dermal sinus. CT scan and MRI are the methods of choice for further investigation of suspect congenital dermal lesions. Neurosurgical treatment of these malformations should be planned early to prevent the high incidence of infections such as bacterial meningitis and cerebellar abscess. Clinical presentation, diagnostic evaluation, and treatment of these rare lesions are reviewed. 相似文献
29.
Our previous findings showed that chronic ethanol feeding lowers blood pressure in spontaneously hypertensive rats. The present study investigated the role of the adenosine receptor-endothelial nitric oxide (NO) pathway in the hypotensive response to ethanol. Changes in blood pressure were evaluated in radiotelemetered pair-fed rats receiving liquid diet with or without ethanol (2.5% or 5%, w/v) for 12 weeks. The vasorelaxant activity of the adenosine analogue 5'-N-ethylcarboxamidoadenosine (NECA) in isolated aortic rings obtained from ethanol and control rats were evaluated. Ethanol (2.5% and 5%) lowered blood pressure in a dose-dependent manner. The hypotension started at week 1, reached its maximum at week 4 and remained so thereafter. In aortas with intact endothelium, NECA (10(-10) to 10(-4) M) produced a concentration-dependent relaxation of the phenylephrine-precontracted aortas. Compared with control rats, ethanol (2.5% and 5%) caused significant and concentration-related increases in NECA responses. This effect of ethanol was attenuated by the adenosine receptor antagonist 8-sulfophenyltheophylline and the nitric oxide synthase inhibitor N(G)-monomethyl-L-arginine (L-NMMA). Further, endothelium denudation abolished the ethanol-evoked enhancement of NECA responses. The vasorelaxant responses to acetylcholine or sodium nitroprusside in aortic rings were not influenced by ethanol. In conclusion, the present findings suggest that chronic ethanol enhances the NO-dependent vasorelaxant responses to adenosine receptor activation and this may explain, at least partly, the mechanism of the hypotensive effect of ethanol in spontaneously hypertensive rats. 相似文献
30.
Dermatomyositis and malignancy in Tunisia: a multicenter national retrospective study of 20 cases 总被引:5,自引:0,他引:5
Mebazâa A Boussen H Nouira R Rokbani L Ben Osman-Dhahri A Bouaouina N Laouani-Kechrid C Louzir B Zahaf A Kamoun MR 《Journal of the American Academy of Dermatology》2003,48(4):530-534
OBJECTIVE AND METHODS: The aim of our study was to report the epidemiologic, clinical, and biologic profiles of dermatomyositis (DM) associated with malignancy in patients from Tunisia. From January 1982 to January 2000, we collected retrospectively 20 case reports of DM associated with cancer from the different university hospital centers of Tunisia. Initial workup included anamnesis, clinical examination, cancer staging and classification, serum muscle enzymes (creatine phosphokinase, lactate dehydrogenase, aldolase, and transaminases), electromyography, and muscular biopsy. We calculated the median survival and mean value of all the variables. Comparisons of statistical tests were done with the Kruskal-Wallis test. RESULTS: Among the 130 DM cases of our study, 20 were associated with cancer (15.38%). The mean age of our patients was 49.6 years and the sex ratio (female/male) was equal to 3. Cancers were mainly those of the breast (35%) and nasopharynx (25%). DM followed a paraneoplastic course in 90% of the cases. The profile of seric muscular enzymes showed a significant statistical difference (P =.05) between a group of patients with severe muscular weakness and a group with moderate muscle weakness only for creatine kinase. The median survival was 36.5 months after diagnosis of DM and 48.6 months after that of cancer. The 5-year actuarial survival was 38% as related to cancer and 16% as related to DM. Mortality was 45%, in 90% as a result of cancer. CONCLUSIONS: In our study, nasopharyngeal carcinoma represents the second cancer associated with DM, after breast neoplasm, demonstrating the frequency of these 2 cancers in our country. Despite our reduced number of study samples, our study also suggests a relationship between severe muscle weakness and high seric muscle enzymes. 相似文献