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Emulsions are important in numerous fields, including cosmetics, coatings, and biomedical applications. A subset of these structures, oil-in-oil emulsions, are especially intriguing for water sensitive reactions such as polymerizations and catalysis. Widespread use and application of oil-in-oil emulsions is currently limited by the lack of facile and simple methods for preparing suitable surfactants. Herein, we report the ready preparation of oil-in-oil emulsions using 2D nanomaterials as surfactants at the interface of polar and nonpolar organic solvents. Both the edges and basal plane of graphene oxide nanosheets were functionalized with primary alkyl amines and we demonstrated that the length of the alkyl chain dictates the continuous phase of the oil-in-oil emulsions (i.e., nonpolar-in-polar or polar-in-nonpolar). The prepared emulsions are stable at least 5 weeks and we demonstrate they can be used to compartmentalize reagents such that reaction occurs only upon physical agitation. The simplicity and scalability of these oil-in-oil emulsions render them ideal for applications impossible with traditional oil-in-water emulsions, and provide a new interfacial area to explore and exploit.

A method for the synthesis of electroactive polymers is demonstrated, starting with the synthesis of extended conjugation monomers using a three-step process that finishes with Negishi coupling. Negishi coupling is a cross-coupling process in which a chemical precursor is first lithiated, followed by transmetallation with ZnCl2. The resultant organozinc compound can be coupled to a dibrominated aromatic precursor to give the conjugated monomer. Polymer films can be prepared via electropolymerization of the monomer and characterized using cyclic voltammetry and ultraviolet-visible-near infrared (UV-Vis-NIR) spectroscopy. Nanoparticles (NPs) are prepared via emulsion polymerization of the monomer using a two-surfactant system to yield an aqueous dispersion of the polymer NPs. The NPs are characterized using dynamic light scattering, electron microscopy, and UV-Vis-NIR-spectroscopy. Cytocompatibility of NPs is investigated using the cell viability assay. Finally, the NP suspensions are irradiated with a NIR laser to determine their effectiveness as potential materials for photothermal therapy (PTT).

Anal carcinomas are rare and their precancerous conditions are not well known. Two populations at risk are described, elderly women and, recently, homosexual males. Early detection of dysplastic lesions or intraepithelial carcinoma in the anal mucosa could lead to preservation on the anal sphincter and consequently to improvement of quality of survival. The present study included 3 women and 2 men. The pathological examination of the surgical specimens in these 5 cases (hemorrhoidal procidence, rectal prolapsus, fibrous polyps, fissure) showed, in all cases, an intraepithelial carcinoma developed in the squamous epithelium of the anal canal. In one of the 5 cases, the anal lesion was concomitant with an intraepithelial carcinoma of the uterine cervix. Complete local resection of the lesions were performed in all cases, associated with complementary radiotherapy in one patient. On follow-up, we observed one recurrence after 8 months in one out of 5 patients. All patients are alive. Histogically, the specimens showed an intraepithelial carcinoma in all 5 cases, with a microinvasive carcinoma in one case. The transitional mucosa of the anal canal showed dysplatic modification in all cases. Immunohistochemical study of the 5 cases did not discern the papilloma virus antigene. In the one case where it was performed, molecular hybridization showed a type 33 papillomavirus. The risk factors of anal carcinomas seems to be changing, in particularly the incidence is increasing in the homosexual patients. In this particular population, as in the uterine cervix, the human papilloma virus is probably one of the main etiological factors. The management of these lesions is not well-defined.(ABSTRACT TRUNCATED AT 250 WORDS)

Colonic tuberculosis is currently exceptionally rare in western countries. This interesting report reminds of its existence and emphasizes the diagnostic problems with Crohn's disease in the past. The barium enema enables to show the main aspects of colonic tuberculosis, i.e. variable forms of stenosis. The contribution of colonoscopy is essential in defining the lesions and allowing multiple biopsies. These biopsies may show the presence of granulomas with caseous necrosis, and possibly the Koch Bacillus on direct examination or in culture. The conditions of prescription of the medical treatment are similar to that of other tuberculous locations. Surgery is indicated in the presence of complications, when there is a doubt the malignant nature of the lesion, finally at the stage of cicatricial stenosis.

The authors report a study of 40 patients affected with "essential" ano-rectal neuralgia. It manifests itself by frequent urinary disorders discovered most of the time at the interview of the patient and emphasizes in many cases the presence of psychosomatic disorders. This study has also demonstrated frequent abnormalities of laboratory tests including: chlamydiae serology, urethral samplings and cyto-bacteriological examination of urine looking for: chlamydiae, ureaplasma urealyticum, mycoplasma hominis and common urinary infections. Results of the treatment seemed completely favorable but should be confirmed by a long-term analysis.