979 resultados para Anal Vesicle


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BACKGROUND: To evaluate the outcome of patients with carcinoma of anal margin in terms of recurrence, survival, and radiation toxicity. METHODS: A series of 45 consecutive patients, with anal margin carcinoma treated between 1983 and 2006 with curative intent at two institutions, was retrospectively analyzed. A surgical excision (close or positive surgical margin in 22 out of 29 patients) was realized before radiotherapy (RT). RT consisted of definitive external beam RT (EBRT) in 36 patients, brachytherapy (BT) alone in two patients, and both BT and EBRT in seven patients. The median total radiation dose was 59.4 Gy (range, 30-74 Gy). RESULTS: The 5-year locoregional control (LRC) rate was 78% [95% confidence interval (CI), 64-93%]. The 5-year disease-specific survival (DSS) and overall survival (OS) rates were respectively 86% (95% CI, 72-99%) and 55% (95% CI, 44-66%). The overall anal conservation rate was 80% for the whole series. There was no significant association between local recurrence and patient age, histological grade, tumor size, T stage, overall treatment time, RT dose, or chemotherapy. Long-term side effects were observed in 15 patients (33%). Only three patients developed grade 3-4 late toxicity (CTCAE/NCI v3.0). Significant relationship was found between dose, and complication rate (48% for dose >or=59.4 Gy versus 8% for dose < 59.4 Gy; P = 0.03). CONCLUSIONS: We conclude that definitive RT and/or BT yield a good local control and disease-specific survival comparable with published data. This study suggests that radiation dose over 59.4 Gy seems to increase treatment-related morbidity.

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OBJECTIVE: Our objective is to describe pouchography, CT, and MRI features of the J-shaped pouch, both normal and with pouch-related complications. CONCLUSION: Pouchography is performed before closure of the loop ileostomy to assess the integrity of the ileal pouch and anastomosis. CT and MRI can be performed when postoperative complications, such as small-bowel obstruction, pouchitis, leakage, abscess, intramural hematoma, desmoid tumor, or recurrent Crohn's disease, are suspected.

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Syntaxin 1 and synaptosome-associated protein of 25 kD (SNAP-25) are neuronal plasmalemma proteins that appear to be essential for exocytosis of synaptic vesicles (SVs). Both proteins form a complex with synaptobrevin, an intrinsic membrane protein of SVs. This binding is thought to be responsible for vesicle docking and apparently precedes membrane fusion. According to the current concept, syntaxin 1 and SNAP-25 are members of larger protein families, collectively designated as target-SNAP receptors (t-SNAREs), whose specific localization to subcellular membranes define where transport vesicles bind and fuse. Here we demonstrate that major pools of syntaxin 1 and SNAP-25 recycle with SVs. Both proteins cofractionate with SVs and clathrin-coated vesicles upon subcellular fractionation. Using recombinant proteins as standards for quantitation, we found that syntaxin 1 and SNAP-25 each comprise approximately 3% of the total protein in highly purified SVs. Thus, both proteins are significant components of SVs although less abundant than synaptobrevin (8.7% of the total protein). Immunoisolation of vesicles using synaptophysin and syntaxin specific antibodies revealed that most SVs contain syntaxin 1. The widespread distribution of both syntaxin 1 and SNAP-25 on SVs was further confirmed by immunogold electron microscopy. Botulinum neurotoxin C1, a toxin that blocks exocytosis by proteolyzing syntaxin 1, preferentially cleaves vesicular syntaxin 1. We conclude that t-SNAREs participate in SV recycling in what may be functionally distinct forms.

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BACKGROUND: Anal condylomata acuminata (ACA) are caused by human papilloma virus (HPV) infection which is transmitted by close physical and sexual contact. The result of surgical treatment of ACA has an overall success rate of 71% to 93%, with a recurrence rate between 4% and 29%. The aim of this study was to assess a possible association between HPV type and ACA recurrence after surgical treatment. METHODS: We performed a retrospective analysis of 140 consecutive patients who underwent surgery for ACA from January 1990 to December 2005 at our tertiary University Hospital. We confirmed ACA by histopathological analysis and determined the HPV typing using the polymerase chain reaction. Patients gave consent for HPV testing and completed a questionnaire. We looked at the association of ACA, HPV typing, and HIV disease. We used chi, the Monte Carlo simulation, and Wilcoxon tests for statistical analysis. RESULTS: Among the 140 patients (123 M/17 F), HPV 6 and 11 were the most frequently encountered viruses (51% and 28%, respectively). Recurrence occurred in 35 (25%) patients. HPV 11 was present in 19 (41%) of these recurrences, which is statistically significant, when compared with other HPVs. There was no significant difference between recurrence rates in the 33 (24%) HIV-positive and the HIV-negative patients. CONCLUSIONS: HPV 11 is associated with higher recurrence rate of ACA. This makes routine clinical HPV typing questionable. Follow-up is required to identify recurrence and to treat it early, especially if HPV 11 has been identified.

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Chemokines are small chemotactic molecules widely expressed throughout the central nervous system. A number of papers, during the past few years, have suggested that they have physiological functions in addition to their roles in neuroinflammatory diseases. In this context, the best evidence concerns the CXC-chemokine stromal cell-derived factor (SDF-1alpha or CXCL12) and its receptor CXCR4, whose signalling cascade is also implicated in the glutamate release process from astrocytes. Recently, astrocytic synaptic like microvesicles (SLMVs) that express vesicular glutamate transporters (VGLUTs) and are able to release glutamate by Ca(2+)-dependent regulated exocytosis, have been described both in tissue and in cultured astrocytes. Here, in order to elucidate whether SDF-1alpha/CXCR4 system can participate to the brain fast communication systems, we investigated whether the activation of CXCR4 receptor triggers glutamate exocytosis in astrocytes. By using total internal reflection (TIRF) microscopy and the membrane-fluorescent styryl dye FM4-64, we adapted an imaging methodology recently developed to measure exocytosis and recycling in synaptic terminals, and monitored the CXCR4-mediated exocytosis of SLMVs in astrocytes. We analyzed the co-localization of VGLUT with the FM dye at single-vesicle level, and observed the kinetics of the FM dye release during single fusion events. We found that the activation of CXCR4 receptors triggered a burst of exocytosis on a millisecond time scale that involved the release of Ca(2+) from internal stores. These results support the idea that astrocytes can respond to external stimuli and communicate with the neighboring cells via fast release of glutamate.

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OBJECTIVE: To identify prevalence of and factors associated with intentional use of HIV risk reduction practices by men who have sex with men during anal intercourse with casual partners. METHODS: Cross-sectional survey pertaining to the Swiss HIV behavioral surveillance system, using an anonymous self-administered questionnaire in a self-selected sample of men who have sex with men (n = 2953). Multinomial regression was used to estimate factors associated with reporting either "no or inconsistent condom use" or "one or more risk reduction practices" over "consistent condom use." RESULTS: 57.2% reported anal intercourse with casual partner(s) over the last 12 months. Of these, 24.0% declared having used a risk reduction practice (73.8% of those who did not use condoms consistently). HIV-positive people were more likely to have done so. Most predictors were similarly associated to both regression categories. Four significant predictors were common to both regression categories: Internet partner seeking, age, age squared, and the interaction between HIV status positive and number of partners. The only association that differed markedly between the 2 regression categories was having a number of partners above median, significantly associated with the risk reduction category. CONCLUSIONS: Although condom use is the most frequent protection strategy in anal intercourse with casual partners, risk reduction practices are highly prevalent. However, there are no clear differences regarding predictors between risk reduction practices and inconsistent or no condom use. This suggests that risk reduction is an opportunistic response rather than a strategy per se.

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Objective: To report a single-center experience treating patients with squamous- cell carcinoma of the anal canal using helical Tomotherapy (HT) and concurrent chemotherapy (CT).Materials/Methods: From October 2007 to February 2011, 55 patients were treated with HT and concurrent CT (5-fluorouracil/capecitabin and mitomycin) for anal squamous-cell carcinoma. All patients underwent computed- tomography-based treatment planning, with pelvic and inguinal nodes receiving 36 Gy in 1.8 Gy/fraction. Following a planned 1-week break, primary tumor site and involved nodes were boosted to a total dose 59.4 Gy in 1.8 Gy/fraction. Dose-volume histograms of several organs at risk (OAR; bladder, small intestine, rectum, femoral heads, penile bulb, external genitalia) were assessed in terms of conformal avoidance. All toxicity was scored according to the CTCAE, v.3.0. HT plans and treatment were implemented using the Tomotherapy, Inc. software and hardware. For dosimetric comparisons, 3D RT and/or IMRT plans were also computed for some of the patients using the CMS planning system, for treatment with 6-18 MV photons and/or electrons with suitable energies from a Siemens Primus linear accelerator equipped with a multileaf collimator.Locoregional control and survival curves were compared with the log-rank test, and multivariate analysis by the Cox model.Results: With 360-degree-of-freedom beam projection, HT has an advantage over other RT techniques (3D or 5-field step-and-shot IMRT). There is significant improvement over 3D or 5-field IMRT plans in terms of dose conformity around the PTV, and dose gradients are steeper outside the target volume, resulting in reduced doses to OARs. Using HT, acute toxicity was acceptable, and seemed to be better than historical standards.Conclusions: Our results suggest that HT combined with concurrent CT for anal cancer is effective and tolerable. Compared to 3D RT or 5-field step-andshot IMRT, there is better conformity around the PTV, and better OAR sparing.

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PURPOSE: To assess the feasibility and activity of radio-chemotherapy with mitomycin C (MMC) and cisplatin (CDDP) in locally advanced squamous cell anal carcinoma with reference to radiotherapy (RT) combined with MMC and fluorouracil (5-FU). PATIENTS AND METHODS: Patients with measurable disease >4 cmN0 or N+ received RT (36Gy+2 week gap+23.4Gy) with either MMC/CDDP or MMC/5-FU (MMC 10mg/m(2) d1 of each sequence; 5-FU 200mg/m(2)/day c.i.v. daily; CDDP 25mg/m(2) weekly). Forty patients/arm were needed to exclude a RECIST objective response rate (ORR), 8 weeks after treatment, of <75% (Fleming 1, alpha=10%, beta=10%). RESULTS: The ORR was 79.5% (31/39) (lower bound confidence interval [CI]: 68.8%) with MMC/5-FU versus 91.9% (34/ 37) (lower bound CI: 82.8%) with MMC/CDDP. In the MMC/5-FU group, two patients (5.1%) discontinued treatment due to toxicity versus 11 (29.7%) in the MMC/CDDP group. Nine grade 3 haematological events occurred with MMC/CDDP versus none with 5-FU/MMC. The rate of other toxicities did not differ. There was no toxic death. Thirty-one patients in the MMC/5-FU arm (79.5%) and 18 in the MMC/CDDP arm (48.6%) were fully compliant with the protocol treatment (p=0.005). CONCLUSIONS: Radio-chemotherapy with MMC/CDDP seems promising as only MMC/CDDP demonstrated enough activity (RECIST ORR >75%) to be tested further in phase III trials; MMC/5-FU did not. MMC/CDDP also had an overall acceptable toxicity profile.

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The aim of this study was to analyze the circumstances of first anal intercourse (FAI) among men who have sex with men (MSM) and to identify factors associated with condom use at this event. We conducted a cross-sectional survey among a convenience sample of MSM living in Switzerland (N = 2,200). Anonymous questionnaires were distributed using Swiss gay communication channels (newspapers, associations, websites) and gay bathhouses. We gathered data on age at FAI, age of the partner, degree of familiarity with him, place of first meeting, and sociodemographic indicators. We did not ask whether FAI was insertive, receptive, or both. Data were stratified by birth year classes (birth cohorts). The median age at FAI fell from 24.5 years among men born before 1965 to 20.0 years among those born between 1975 and 1984 (p < .001). In each birth cohort, between 20 and 30% reported a partner 10 years older or more. Of eight variables examined in multivariate analysis, two were positively associated with condom use: age of participants at FAI and low degree of familiarity between partners. Conversely, large age discrepancy between partners was negatively associated with condom use. In conclusion, our data showed that early initiation of anal intercourse and large age discrepancy were associated with risk taking: a pattern of initiation that may facilitate HIV transmission from older to younger cohorts of MSM. Since age at FAI is on the decrease, there is an urgent need to heighten awareness of prevention actions regarding sexual debut of MSM.

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Résumé : Le condylome acuminé anal (CAA), transmis par contact sexuel, résulte d'une infection par Human Papilloma Virus (HPV). Son traitement chirurgical est grevé d'un taux de récidive de 4-29%. Le but de cette étude était d'identifier une éventuelle corrélation entre type d'HPV présent dans les CAA excisés chirurgicalement et taux de récidive de la maladie, Cette étude rétrospective porte sur 140 patients opérés au Centre Hospitalier Universitaire Vaudois de CAA, entre 1990 et 2005. Le diagnostic lésionnel a été confirmé par un examen histomorphologique. Le(s) type(s) d'HPV présent(s) dans ces lésions a été déterminé par Polymerase Chain Reaction (PCR). Les patients ont donné leur accord à cette analyse et complété un questionnaire. Une éventuelle corrélation entre récidive de CAA, type d'HPV et status HIV a été recherchée. HPV 6 et 11 sont les virus les plus fréquemment découverts (51% et 28%, respectivement) chez les 140 patients (123H/17F). Trente-cinq (25%) d'entre eux ont présenté une récidive. HPV 11 était present chez 19 (41%) sujets. Ceci est statistiquement significatif (P<0.05), en comparaison aux autres HPVs. Il n'y a par contre pas de différence significative entre la fréquence de récidive des 33 (24%) patients HIV-positifs et le reste du collectif. HPV 11 est donc associé à un taux de récidive de CAA significativement élevé. Un suivi strict des patients atteints est nécessaire pour identifier une récidive et la traiter sans délai, notamment lorsque HPV 11 est present. Ces résultats innovateurs soulèvent la question de la nécessité de pratiquer une typisation virale systématique sur les lésions excisées. La justification d'une telle attitude demande toutefois encore d'être confirmée.

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Anal pain is a common reason for consultation, whose etiology is varied and should not be limited to the hemorrhoidal disease. The purpose of this article is to conduct a review of the literature on anorectal pathologies most frequently encountered and make recommendations regarding their management.

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One hundred twenty-two early-stage anal canal cancer patients (median age: 69 years) were treated with curative radiotherapy with (70 patients) or without (52 patients) concomitant chemotherapy. Median follow-up was 65 months (range: 4-238). At multivariate analysis, concomitant chemotherapy significantly improved local control (p = .007). Local control significantly influenced all considered endpoints, except the metastases free survival. The global rates of G3-G4 acute and late toxicity were 13.1% and 8.2%, respectively, and they were not increased by concomitant chemotherapy. Finally, concomitant chemotherapy is efficacious and safe in the treatment of T1-2N0 anal canal cancer patients and should be prospectively studied.

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AIMS AND BACKGROUND: The standard treatment of anal canal cancer (ACC) is combined chemotherapy and radiation therapy (RT), which is complex because of the shape of the target volumes and the need to minimize the irradiation of normal pelvic structures. In this study we compared the dosimetric results of helical tomotherapy (HT) plans with traditional 3D conformal RT (3DRT) plans for the treatment of ACC. METHODS AND STUDY DESIGN: Twelve patients (median age 57 years, range 38-83; F/M 8/4) treated with HT and concurrent chemotherapy for locally advanced ACC were selected. All had histologically confirmed squamous-cell carcinoma. A clinical target volume including the tumor and pelvic and inguinal lymph nodes was treated with HT to a total dose of 36 Gy in 1.8-Gy daily fractions. Then a sequential boost of 23.4 Gy in 1.8-Gy daily fractions (total dose 59.4 Gy) was delivered to the tumor and involved nodes. For all 12 patients, 3DRT plans were generated for comparison. Treatment plans were evaluated by means of standard dose-volume histograms. Dose coverage of the planning target volumes (PTVs), homogeneity index (HI), and mean doses to organs at risk (OARs) were compared. RESULTS: The coverage of PTV was comparable between the two treatment plans. HI was better in the HT vs. 3DRT plans (1.25 and 3.57, respectively; p<0.0001). HT plans resulted in better sparing of OARs (p<0.0001). CONCLUSIONS: HT showed superior target dose conformality and significant sparing of pelvic structures compared with 3DRT. Further investigation should determine if these dosimetric improvements will improve clinical outcomes regarding locoregional control, survival, and treatment-related acute and late morbidity.

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BACKGROUND AND PURPOSE: There are few data on long-term clinical results and tolerance of brachytherapy in anal canal cancer. We present one of the largest retrospective analyses of anal canal cancers treated with external beam radiotherapy with/without (±) chemotherapy followed by a brachytherapy boost. MATERIALS AND METHODS: We performed a retrospective analysis of clinical results in terms of efficacy and toxicity. The impact of different clinical and therapeutic variables on these outcomes was studied. RESULTS: From May 1992 to December 2009, 209 patients received brachytherapy after external beam radiotherapy ± chemotherapy. Of these patients, 163 were stage II or stage IIIA (UICC 2002) and 58 were N1-3. According to age, ECOG performance status (PS), and comorbidities, patients received either radiotherapy alone (58/209) or radiochemotherapy (151/209). The median follow-up was 72.8 months. The 5- and 10-year local control rates were 78.6 and 73.9 %, respectively. Globally, severe acute and late G3-4 reactions (NCI-CTC scale v. 4.0) occurred in 11.2 and 6.3 % of patients, respectively. Univariate analysis showed the statistical impact of the pelvic treatment volume (p = 0.046) and of the total dose (p = 0.02) on the risk of severe acute and late toxicities, respectively. Only six patients required permanent colostomy because of severe late anorectal toxicities. CONCLUSION: After a long follow-up time, brachytherapy showed an acceptable toxicity profile and high local control rates in patients with anal canal cancer.