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The difference between in-plane and out-of-plane bonding energy of transition metal dichalcogenides has provided the possibility of isolating single layers. A one step synthesis protocol to produce size-controlled single layers has always been challenging. Here we developed a new colloidal synthesis to produce monodisperse size-controlled 1T'-WS2 nano-monolayers with outstanding colloidal stability by using 1-octadecanethiol as the coordinating agent. Changes in the reaction time and amount of coordinating agent regulate the mean size of the nanosheets. We investigated the effect of octadecanethiol and injection rate on the dispersion and mean-size, using UV-Vis spectroscopy, X-ray diffraction techniques, and transmission electron microscopy. Furthermore, thermogravimetric analysis and Fourier transform infrared spectroscopy allow for ligands detection and analysis at the surface of the nanosheets. These results open a new pathway to synthesize, control and explore the properties of nanoscale transition metal dichalcogenides.

International audience; Complex architectures like 3D gold dendritic nanostructures were synthesized by an in situ templated growth method using a thin film of a block copolymer [polystyrene-b-poly(4-vinylpyridine)] deposited onto silicon substrates. The overall study has demonstrated the strong link between the morphology, size, and distribution of the structures and the synthetic physicochemical parameters, such as pH, reaction temperature, concentration, and nature of reactants. A nonequilibirum state of the medium has been required to create a fractal growth of the gold structures onto a prepatterned gold-seeded surface and has led to a better control of the structures' surface coverage rate. Those as-prepared nanodendrites have also exhibited high electrocatalytic activity toward a significant enhancement factor, as well as important sensitivity, thanks to tip effects. The electrochemical experiment results have demonstrated efficient adsorption and quantification of very low traces of specific molecules like glutathione or hexadecanethiol.

The necessity for routine histopathologic evaluation of hemorrhoidectomy specimens considered free of suspicious areas after careful visual and manual inspection remains controversial.The purpose of this work was to prospectively study the prevalence of anal intraepithelial neoplasia in macroscopically normal operative specimens.From October 2005 to September 2010, all hemorrhoidectomy and fissurectomy specimens were sent for routine histopathologic analysis.This study was conducted at a tertiary referral center.The primary outcome measured was the histopathologic examination of surgical samples.Among the specimens from 2997 procedures, routine histopathologic evaluation found anal intraepithelial neoplasia in 97 patients (3.2%), despite the fact that visual and manual inspection had determined that the specimens were free of any suspected anal intraepithelial neoplasia or human papillomavirus-related lesion. The pathological diagnoses for these macroscopically normal specimens were AIN1 in 22 (23%) patients, AIN2 in 48 (49%) patients and AIN3 in 27 (28%) patients, making the prevalence of high-grade and low-grade disease 2.5% (anal intraepithelial neoplasia 2/3) and 0.7% (anal intraepithelial neoplasia 1).This study was limited by being a single-center study.This prospective single-center study demonstrated that the prevalence of infraclinical anal intraepithelial neoplasia in macroscopically normal hemorrhoidectomy and fissurectomy specimens is not negligible (3.2% with 2.5% high-grade disease).

This paper relates the development of a French incoherent scatter system which started its operations in 1965. This development took place several years after the initial implementation of such systems in the United States, in Peru and in the United Kingdom. The French system, owing to its bistatic configuration and the use of continuous waves, differed from the previous ones. These characteristics yielded signals of excellent spectral quality, unravelling the possibility of inferring physical parameters (Doppler shift, average ion mass) out of reach, at that time, of other systems. The possibility of making ion drift vector measurements led to extend the system into a quadristatic configuration. The multiple capabilities offered by the incoherent scatter technique, notably as concerns the thermodynamical properties of the ionosphere and of the thermosphere, led further the French community to a project of embarking an incoherent scatter radar on board a ship. Taking account of a project of a Scandinavian auroral zone radar and of the considerable interest of the study of auroral zone electrodynamics, the French community abandoned the idea of the ship and expressed an interest in joining the Scandinavian project in conjunction with Germany and the United Kingdom.

Resume But Evaluer l’impact de la TEP/TDM au FDG sur la prise en charge du patient adresse pour la stadification et/ou le suivi d’un cancer anal. Patients et methodes Nous avons inclus les patients adresses dans le service pour cancer du canal anal dont la prise en charge therapeutique etait evaluable grâce a un suivi d’au moins six mois. Resultats Les resultats de 44 patients ont ete analyses : 22 avaient eu un examen TEP/TDM pour la stadification initiale et 36 dans le suivi. La TEP/TDM a eu un impact chez neuf patients sur 44 (20 %) et il etait pertinent chez huit d’entre eux. Conclusion La TEP/TDM est une modalite d’imagerie fiable pour le cancer du canal anal, en particulier dans le suivi en cas de suspicion de persistance ou de recidive de la maladie ou son impact sur la prise en charge du patient a ete le plus net.

Recto-urethral fistulas in Crohn's disease are rare, and managing them is difficult. The various surgical techniques are not reliably effective and are associated with a significant risk of morbidity. The rectal mucosal transposition flap technique, which is used most frequently, requires the rectal mucosa to be in a healthy condition. We report here on a case where treatment was by injecting fibrin glue into a complex fistula with a single anorectal point of origin but combining a median recto-urethrocutaneous tract with two deep lateral rectoperineal tracts. The patient had presented with active rectal Crohn's disease. This treatment produced complete closure, verified by MRI, of all the fistula tracts, which was still maintained after three years, and with normal anal continence. When confronted with this type of fistula, and particularly when the condition of the rectal mucosa is poor, the specialist should be encouraged by this good result to consider the injection of fibrin glue, a technique without risk of morbidity, as a first course of action.

The incidence of radiation-induced chronic hemorrhagic proctitis is less than 10 to 20%. The onset of this proctitis is delayed relative to the radiation therapy and generally develops from 6 to 24 months later. There are numerous predisposing factors, the most important of which is the radiation therapy dose: risk increases exponentially above 40-45 Gy. Its pathophysiology involves progressive obliterating endarteritis and transmural interstitial fibrosis, which induce chronic ischemia that is irreversible and progressive during the years after radiation therapy. Its diagnosis depends most often on the combination of clinical history and typical endoscopic appearance (congestive mucosa and/or telangiectases). Topical administrative of sucralfate or corticosteroids as well as argon plasma coagulation, with formalin treatment if necessary, provides relief for most patients.

La proctalgie fugace est une algie ano-rectale intermittente evoluant en general de facon chronique. Sa prevalence dans la population generale varie entre 3 et 15 % avec une predominance feminine. L’âge moyen de survenue de la premiere crise douloureuse se situe entre 45 et 55 ans. Le diagnostic repose sur l’interrogatoire. Typiquement, la douleur est d’apparition brutale et inopinee sans facteur declenchant. Elle semble survenir plus volontiers la nuit. Elle est d’emblee paroxystique et en general intense. Elle siege au niveau du canal anal et/ou du bas rectum, et n’irradie pas. Elle est decrite comme une crampe, un spasme ou un coup de poignard. Sa duree est variable, mais elle cesse completement de facon spontanee. Les patients sont asymptomatiques entre les crises. L’examen clinique ainsi que les explorations complementaires sont normaux. Le mecanisme n’est pas clair mais l’hypothese d’un spasme du sphincter interne anal et/ou de la musculeuse rectale est le plus probable. Une simple explication sur la benignite de leurs douleurs suffit a rassurer l’immense majorite des patients.

Anal epidermoid carcinoma is a rare malignant tumor, comprising less than 5% of all carcinomas of the colon, rectum, and anus. The primary therapy now includes radiotherapy, often in combination with chemotherapy. Radical surgery is now rarely indicated. Therapeutic indications are based on locoregional staging, the presence of visceral metastases and an evaluation of the medical history. Anorectal endosonography is helpful in evaluating locoregional extension. In addition, magnetic resonance imaging, positron emission tomography scanning and inguinal sentinel lymph node procedure should play a role in a more selective approach in patients with anal carcinoma.

Summary Introduction Primary anal actinomycosis of cryptoglandular origin, mainly due to Actinomyces israelii , a specific and rare cause of anal suppurative disease, needs to be recognized because it can be cured using specific treatments. Method Data were reviewed from 6 patients with actinomycotic anal abscesses of obvious cryptoglandular origin observed in a single proctology unit between 1983 and 2000. Therapeutic management included conventional surgical treatment of anal sepsis followed by a specific oral antibiotic therapy maintained until the surgical wound had completely healed. Results All but one of the patients were men (median age, 53 years). All abscesses, except one, were indolent. No patient presented macroscopic ″sulphur granules″ in the pus, but one presented ″watery pus″. The diagnosis was established by histological study of the surgically excised tissue or by anaerobic culture of the pus. In the one HIV-positive patient, an uncommon organism was isolated: Actinomyces meyeri . Two cases of recurrence were observed without evidence of Actinomyces infection. Conclusion Actinomycosis should be suspected particularly in indolent anal suppuration. The absence of macroscopic ″sulphur granules″ does not mean this diagnosis can be ruled out. Careful histological examination of the excised tissue and appropriate anaerobic cultures of pus should be carried out to achieve complete eradication of this rare, but easily curable disease.

Aim The clinicopathological and virological characteristics of anal superficially invasive squamous-cell carcinoma (SISCCA) were determined. Method Seventeen patients with a completely excised stage T1N0M0 anal squamous-cell carcinoma (SCC) were included in the study. The tumours were divided into superficially invasive and invasive. Patients with anal high-grade squamous intraepithelial dysplasia, which corresponded to anal intraepithelial neoplasia (AIN) Grades 2 or 3, were used as a control group. Clinicopathological and virological characteristics were investigated. Overall survival and cancer recurrence-free survival were also assessed. Results Of the 17 patients, 12 (70.5%) were men. Ten (58.8%) were human immunodeficiency virus positive. Seven (41%) patients met the same diagnostic criteria as those recently proposed for anal SISCCA. According to the results obtained using the polymerase chain reaction, human papillomavirus (HPV) 16 was the most commonly detected (94%) type of HPV. Twelve (70.6%) patients with an inadequate surgical margin around the tumour received adjuvant radiotherapy, including the two (11.7%) tumours that locally recurred, one of which was an anal SISCCA. Superficially invasive anal cancers differed from the other T1N0M0 anal carcinomas according to the clinical presentation and the absence of lymph-vascular invasion (LVI). There were no differences in cancer recurrence-free and overall survival rates between the superficially invasive and invasive groups. Conclusion Anal SISCCAs have a low index of clinical suspicion, are associated with an absence of LVI and are linked to high-risk HPV. Prospective studies are needed to define the clinical behaviour of these anal tumours and to determine their best therapeutic strategy.

L’utilisation de l’IRM dans le bilan des suppurations ano-perineales est relativement recente. En effet, la region ano-perineale etant superficielle et facile d’acces, son exploration a longtemps ete cantonnee a l’examen clinique proctologique, qui est suffisant dans la majorite des situations. Puis cet examen s’est enrichi des techniques d’imagerie [1, 2], tout d’abord l’echographie endo-anale [3–5], qui s’est averee tres utile dans les cas difficiles. L’IRM s’est ensuite imposee [6–8] dans le bilan des suppurations complexes ou posant des problemes difficiles de prise en charge et tout particulierement en cas de lesions ano-perineales de la maladie de Crohn (LAPMC) [9]. Elle a permis en outre de preciser l’anatomie de cette region du fait de sa capacite a imager les parties molles.

Une fistule anale d'origine cryptoglandulaire peut-elle etre d'origine sarcoidosique? Si oui, en raison de leur parente sur le plan histologique, quels sont les elements discriminants avec les fistules anales dela maladie de Crohn?

BACKGROUND: The performance of cytologic screening and its correlation with histology and polymerase chain reaction (PCR) detection of human papillomavirus (HPV) DNA have not been evaluated in populations with a low prevalence of anal intraepithelial neoplasia (AIN). The objective of the current study was to analyze the significance of abnormal smears relative to the histology and PCR detection of HPV DNA. METHODS: A cytologic smear and a viral sample were taken in 300 consecutive patients undergoing surgery (Milligan-Morgan hemorrhoidectomy and/or fissurectomy) who gave their informed consent. RESULTS: The cytologic smear was normal in 216 of 290 patients (74.5%). Four high-grade and 19 low-grade intraepithelial neoplastic lesions were identified. In 5 patients, high-grade lesions could not be excluded, 30 lesions were of undetermined significance, and there were 16 cellular modifications with a non-neoplastic appearance. The PCR test for HPV was positive in 18.7% of patients, and a high-risk genotype was identified in 63.6% of positive samples. Histologic examination of the surgical samples was normal in 92.3% of patients. The 23 AIN samples were distributed as follows: 13 grade 1 AIN (AIN1), 6 AIN2, and 4 AIN3. The sensitivity of cytologic smears and PCR for detecting AIN was 56% and 60.8%, respectively, and specificity was 77% and 84.5%, respectively. Combining the 2 tests increased sensitivity to 78% but decreased specificity to 68%. CONCLUSIONS: Compared with a large surgical sample, anal cytologic Papanicolaou smears and HPV PCR exhibited sensitivity and specificity that varied, depending on the risk of HPV infection and AIN. Positive HPV DNA screening increased with AIN grade, and high-risk HPV testing was particularly helpful. Cancer 2012. © 2012 American Cancer Society.

The purpose of the study was to assess the diagnostic performance of positron emission tomography/computed tomography and fluorodeoxyglucose (18F) (FDG PET/CT) for the staging and the follow-up of anal carcinoma, and to evaluate the impact of FDG PET/CT on patient management.Patients with anal carcinoma were referred to our department from October 2004 until July 2008. The diagnostic performance was evaluated on a perexamination basis and on a per-site basis, together with impact of PET/CT on patient management. The standard of truth was histology when available and, in all cases, follow-up data during at least 6 months.Fifty-eight FDG PET/CT performed in 44 patients were analysed—22 for initial staging and 36 during follow-up. The detection rate of non-excised tumours on initial examination was 93%. During post-treatment follow-up, FDG PET/CT had, on a per-examination basis, sensitivity for the detection of persistent or recurrent disease of 93% and specificity of 81%, and on a per-site basis, 86% and 97%, respectively. Its negative predictive value was 94% on a per-examination basis and 98% on a per-site basis. FDG PET/CT had an impact on management in nine patients out of 44 (20%), which was relevant in eight of them (89%).FDG PET/CT is an accurate imaging modality in anal cancer. It has an interesting added value during post-treatment follow-up, especially when persistence or recurrence of disease is suspected. Further studies are needed to evaluate whether surveillance by means of FDG PET/CT might have a positive impact on overall survival.

Objective The study aimed to evaluate the efficacy of fibrin glue in the treatment of complex anal fistula. Method Thirty consecutive patients with a complex anal fistula underwent glue instillation after an 8 week period of seton drainage. Cure was defined as complete closure of any secondary opening, absence of fistula seepage, and no abscess formation. Results The mean age of the patients (15 males) was 40.5 (range, 22.8–69.1) years. The mean duration of follow-up was 11.7 (range, 0.2–33.5) months. Complete closure of the fistula was achieved in 17 patients at 1 month but in two patients a delayed abscess occurred. At the end of follow-up, 15 (50%) patients were considered to have been cured. The success rate was no different in cases of Crohn’s disease or when postoperative antibiotic therapy was given. There was, however, a significant difference in success following regional vs general anaesthesia (68.4 vs 18.2% success, P = 0.02). Conclusion Fibrin glue cured 50% of our first 30 patients, and regional anaesthesia was predictive of success.

Cryptoglandular anal fistulae are the most frequently occurring form of perianal sepsis. Characteristically they have an endoanal primary opening, a fistula track and an abscess and/or an external purulent opening. Antibiotic therapy is not of use in initial management except in special cases. Treatment of an abscess, if present, is required urgently and when possible, consists of its incision under local anaesthesia. Treating the fistula track occurs afterwards and aims to dry up the purulent discharge and avoid recurrence of the abscess by means of surgical fistulotomy. These techniques are very effective in terms of eradication of the problem but there is sometimes a risk of anal incontinence. This explains the increasing interest in sphincter preserving techniques using the advancement of a covering flap of rectal mucosa and the injection of fibrin glue.

Anal epidermoid carcinoma is a rare malignant tumor, comprising less than 5% of all carcinomas of the colon, rectum, and anus. The primary therapy now includes radiotherapy, often in combination with chemotherapy. Radical surgery is now rarely indicated. Therapeutic indications are based on locoregional staging, the presence of visceral metastases and an evaluation of the medical history. Anorectal endosonography is helpful in evaluating locoregional extension. In addition, magnetic resonance imaging, positron emission tomography scanning and inguinal sentinel lymph node procedure should play a role in a more selective approach in patients with anal carcinoma.

The incidence of radiation-induced chronic hemorrhagic proctitis is less than 10 to 20%. The onset of this proctitis is delayed relative to the radiation therapy and generally develops from 6 to 24 months later. There are numerous predisposing factors, the most important of which is the radiation therapy dose: risk increases exponentially above 40-45 Gy. Its pathophysiology involves progressive obliterating endarteritis and transmural interstitial fibrosis, which induce chronic ischemia that is irreversible and progressive during the years after radiation therapy. Its diagnosis depends most often on the combination of clinical history and typical endoscopic appearance (congestive mucosa and/or telangiectases). Topical administrative of sucralfate or corticosteroids as well as argon plasma coagulation, with formalin treatment if necessary, provides relief for most patients.

A superconducting particle accelerator like the LHC (Large Hadron Collider) at CERN, can only be controlled well if the effects of the magnetic field multipoles on the beam are compensated. The demands on a control system solely based on beam feedback may be too high for the requirements to be reached at the specified bandwidth and accuracy. Therefore, we designed a suitable field description for the LHC (FIDEL) as part of the machine control baseline to act as a feed-forward magnetic field prediction system. FIDEL consists of a physical and empirical parametric field model based on magnetic measurements at warm and in cryogenic conditions. The performance of FIDEL is particularly critical at injection when the field decays, and in the initial part of the acceleration when the field snaps back. These dynamic components are both current and time dependent and are not reproducible from cycle to cycle since they also depend on the magnet powering history. In this paper a qualitative and quantitative description of the dynamic field behavior substantiated by a set of scaling laws is presented., peer-reviewed

This prospective study was designed to describe a typical attack of proctalgia fugax. Patients were recruited from May 2003 to June 2004. Whatever the reason for consultation, they were systematically asked: “Do you ever suffer intermittent and recurring anorectal pain lasting for at least three seconds?” If the answer was yes, they were interviewed with a questionnaire and had a proctologic examination. The criterion for proctalgia fugax was a positive answer with a negative examination. The study included 1,809 patients. Fifty-four of these patients (3 percent) had proctalgia fugax and 83 percent of them had never sought medical advice for this problem. The mean age was 51 (range, 18–87) years. Thirty-seven patients were females (69 percent). The onset of pain was sudden and without a trigger factor in 85 percent of cases. Attacks occurred in the daytime (33 percent) as well as at night (35 percent). The pain was described as cramping, spasm-like, or stabbing in 76 percent of cases. It did not radiate in 93 percent of cases. There were no concomitant symptoms in 81 percent of cases. Attacks stopped spontaneously in 67 percent of cases. The average duration was 15 minutes (range, 5 seconds to 90 minutes). The average annual number of attacks was 13 (range, 1–180). Proctalgia fugax affects twice as many females as males at approximately aged 50 years. Commonly the roughly once-monthly attack occurs as a sudden pain with no trigger factor, diurnally as often as nocturnally. The nonradiating cramp, spasm, or stabbing pain, without concomitant symptoms, is most severe on average after 15 minutes and declines spontaneously.

Studying anal cytology to detect intraepithelial neoplasia has been demonstrated to be useful in highly selected populations. This study was designed to determine the frequency of abnormal smears in a wide sample of patients consulting for anorectal symptoms. An anal smear was proposed during each consultation during a three-month period. A total of 205 patients (112 females) were included. After the consultation, visible condylomas were detected in 12 (6 percent) of the cases. Two hundred three (99 percent) smears were able to be analyzed. No case of high-grade squamous intraepithelial lesion was found. Four cases of low-grade squamous intraepithelial lesion were found, all in HIV patients with a history of condylomatous lesions. Forty smears were interpreted as atypical squamous cells of undetermined significance and 159 were normal. The prevalence in this population of low-grade squamous intraepithelial lesion was 19 percent (4/21) in HIV seropositive males, and 15 percent (4/26) in the case of a past history of condyloma. The factors associated with an abnormal smear (low-grade squamous intraepithelial lesion or atypical squamous cells of undetermined significance) were a history of anal condylomatous lesions (odd ratio, 4.9; range, 2.1–11.5), HIV seropositivity (odd ratio, 4; range, 1.6–9.9), and smoking (odd ratio, 2.1; range, 1.1–11.5). This work confirms that the frequency of low-grade squamous intraepithelial lesion is raised in HIV-seropositive males and also where there is a history of condyloma, which corroborates the necessity for regular monitoring and screening of these patients at risk. This study also suggests that the use of tobacco is associated with anal cytologic abnormalities.

We report an anal metastasis from a lung cancer which was diagnosed on symptoms mimicking an acute anal abcess. The diagnosis was based on specific immunohistochemistry.

This prospective study evaluated the efficacy and safety of local formalin application in chronic refractory radiation-induced hemorrhagic proctitis. All patients were treated under anesthesia by direct application of 4 percent formalin to the affected rectal areas. The study included 33 patients (17 women) and was conducted between January 1994 and December 2001. There were 11 anal cancers (33 percent), 11 prostate cancers, 9 cervical or endometrial cancers, 1 bladder cancer, and 1 rectal cancer. The mean number of daily rectal bleeds was 2.7 (range, 0.5–15). Nineteen patients (58 percent) were blood transfusion dependent. Twenty-three patients had only one formalin application and 10 patients required a second application because of the persistent bleeding. The treatment was effective in 23 cases (70 percent): 13 patients had complete cessation of bleeding and 10 patients had only minor bleeding. Six anal or rectal strictures occurred: 4 patients had been treated for anal cancer (36 percent) and 2 patients had been treated for other cancers (9 percent). None of the strictures was malignant. Anal incontinence worsened in 5 patients of the 11 who had been treated for anal cancer (45 percent) and occurred in 4 of the 22 other patients (18 percent). Formalin application is an effective treatment for chronic radiation-induced hemorrhagic proctitis. However, local morbidity is not negligible. This result may be related to the high proportion of anal cancers in the series. In our opinion, therefore, formalin application should be reserved for severe hemorrhagic proctitis refractory to medical treatment and should be thoroughly discussed in cases of anorectal radiation-induced stricture, prior anal incontinence, or treated anal cancer.

The evaluation of purity and thermal conductivity at liquid Helium temperatures of the Niobium to be used in the fabrication of superconducting RF cavities is normally done by measuring the Residual Resistivity Ratio (RRR) of a sample of the material. The relationship between the thermal and the electrical conductivity (Wiedemann-Franz Law) simplifies the task by leading to the measurement of electrical instead of thermal resistance. The RRR is the ratio between the resistances of the sample at room temperature and at the operating temperature of the cavity. A more precise definition is discussed later. The conductivity at low temperatures depends on lattice defects and impurities. Impurities are also important for cavities in a direct way as affecting the RF properties of its surface when exposed by chemical etching. The following describes the experimental apparatus for RRR measurements developed at Fermilab's Beams Division. Part 2 contains a description of the sample-holder and measurement hardware. Part 3 contains a discussion on definition, measurements and errors. Part 4 gives a step-by-step description of the measurement procedure. Finally, Part 5 gives an example of results obtained recently on a Niobium sample for CKM cavities.

Purpose Anoperineal tuberculosis is a rare extrapulmonary form of the disease that we must learn to recognize because it requires specific treatment. Methods Data from seven patients with anoperineal tuberculosis observed in a Parisian proctology unit between 1982 and 1999 were reviewed. Results All the patients were male (median age, 55 years); five were born in underdeveloped countries, and two were still living there. The average length of time between first manifestation of the disease and diagnosis was three years (range, 3 months to 9 years); all patients had undergone surgery previously. There were six recurring anal fistulas (complex in 5 cases) and one recurring abscess. In every case, the diagnosis had been suspected or confirmed by systematic histologic study of the surgically excised tissue. An association with pulmonary tuberculosis was found in each case. Treatment included two parts: conventional surgical treatment of anal sepsis and specific medical antituberculosis treatment. Evolution was favorable in all cases, with no recurrence of disease. Human immunodeficiency virus infection did not increase the incidence of anoperineal tuberculosis. Conclusion Tuberculosis should be suspected in all recurrent fistulas. Histologic examination of the excised tissue and a lung x-ray should be performed to avoid delay in diagnosing an easily curable disease.

We report an anal metastasis from a lung cancer which was diagnosed on symptoms mimicking an acute anal abcess. The diagnosis was based on specific immunohistochemistry.