A conductometric enzymatic methanol sensor based on polystyrene - PAMAM dendritic polymer electrospun nanofibers.

Methanol (MeOH) is a solvent and cleaning agent used in industry, but it is poisonous when ingested. The recommended release threshold for MeOH vapor is 200 ppm. We present a novel sensitive micro-conductometric MeOH biosensor created by grafting alcohol oxidase (AOX) onto electrospun polystyrene-poly(amidoamine) dendritic polymer blend nanofibers (PS-PAMAM-ESNFs) on interdigitated electrodes (IDEs). The analytical performance of the MeOH microsensor was evaluated using gaseous MeOH, ethanol, and acetone samples collected from the headspace above aqueous solution with known concentration. The sensor's response time (tRes) fluctuates from 13 s to 35 s from lower to higher concentrations. The conductometric sensor has a sensitivity of 150.53 µS.cm-1 (v/v) for MeOH and a detection limit of 100 ppm in the gas phase. The MeOH sensor is 7.3 times less sensitive to ethanol and 136.8 times less sensitive to acetone. The sensor was verified for detecting MeOH in commercial rubbing alcohol samples.

Direct E-DNA sensor of Mycobacterium tuberculosis mutant strain based on new nanocomposite transducer (Fc-ac-OMPA/MWCNTs).

Direct DNA sensor based on new nanocomposite materials (Fc-ac-OMPA/MWCNTs) has been investigated. This nanocomposite was formed by combining the redox oligomer "oligo-methoxy-phenyl-acetonitrile" (Fc-ac-OMPA) and the MWCNTs via a simple π-π stacking interaction in the aim to ameliorate the biosensor performance. The redox indicator and the functional groups of the redox oligomer have been used for monitoring the electrochemical behavior and the flexibility for direct covalent attachment of Hepatitis C DNA probe. This nanocomposite shows high performance of DNA hybridization with a detection limit of 0.08 fmol L-1. Moreover, the biosensor was applied for the detection of pathogenic bacterium such as DNA from Mycobacterium tuberculosis strand. Developed biosensor has been able to detect a single nucleotide polymorphism (SNP)T (TCG/ TTG) which confers resistance of M. tuberculosis to rifampicin drug.

Direct Electrochemical DNA Sensor based on a new redox oligomer modified with ferrocene and carboxylic acid: Application to the detection of Mycobacterium tuberculosis mutant strain.

A new redox oligomer "oligo-methoxy-phenyl-acetonitrile" (Fc-acid-OMPA) modified with ferrocene groups and carboxylic acids as functional groups in side chains, has been synthesized. The redox indicator has been used for monitoring the electrochemical behavior. The functional groups give the flexibility for direct covalent attachment of biomolecules. The electrochemical properties of the redox oligomer film deposited on gold electrodes have been studied by cyclic voltammetry (CV), which showed a rate of electron transfer of 6.43 s-1. The oligomer has been studied as a transducer for electrochemical DNA sensing and for this purpose the acid functional group of Fc-acid-OMPA was attached with the DNA probe of hepatitis C bearing amino group in 5' position through amid link. The efficiency of DNA attachment on the oligomer film has been analyzed by X-Ray Photoelectron Spectrometry (XPS) and FT-IR spectroscopy. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) have been used to analyze the biosensor construction and DNA detection. A wide linear range of detection from 1 fM to 100 pM have been demonstrated with a limit of detection (LOD) of 0.2 fM. The biosensor has showed an appreciated sensitivity to PCR samples of genomic DNA from Mycobacterium tuberculosis, and has been able to detect a single mutation which confers resistance of M. tuberculosis to rifampicin drug.

Bathing suit ichthyosis caused by a TGM1 mutation in a Tunisian child.

BACKGROUND: Bathing suit ichthyosis (BSI) is an uncommon phenotype classified as a minor variant of autosomal recessive congenital ichthyosis (ARCI). OBJECTIVES: We report a case of BSI in a 3-year-old Tunisian girl with a novel mutation of the transglutaminase 1 gene (TGM1). CASE REPORT: This infant had been born with a collodion membrane encasing her entire body. From the age of three months, brownish scaling was noted on the bathing suit area. Histology showed orthohyperkeratosis with acanthosis of the epidermis. The granular layer was normal, and the superficial dermis was mildly inflammatory, confirming a diagnosis of proliferating ichthyosis. Molecular analysis in the patient and her parents revealed the mutation I304F of TGM1. Treatment with emollients and keratolytics partially improved the patient's skin condition. CONCLUSIONS: Bathing suit ichthyosis is an uncommon phenotype unique in its topography, which involves the trunk but spares the face and extremities. Previous studies using molecular analysis have shown that BSI is caused mainly by mutations in TGM1. Twenty missense mutations have been reported in BSI. Of these 20 missense mutations, nine occurred only in patients with the BSI phenotype and 11 were common to BSI and other types of ARCI. Until recently, there has been no genotype-phenotype correlation. Therefore, the same mutation of the transglutaminase 1 could result in either generalized ARCI or BSI. The present case demonstrates this phenotype in a White Tunisian patient with a novel mutation of TGM1 (I304F) not previously reported in BSI.

A case of linear atrophoderma of Moulin successfully treated with methotrexate.

Linear atrophoderma of Moulin is an acquired rare and self-limited skin condition. It is characterized by atrophic bandlike skin lesions that often show hyperpigmentation and always follow the lines of Blaschko. Usually it begins in childhood or adolescence and there is no evidence of any long term progression. We describe a case of a 21-year-old woman with clinical and histological features of linear atrophoderma of Moulin. The patient was successfully treated with methotrexate 20 mg/week during 6 months with an improvement of skin pigmentation and atrophy. Approximately, 30 cases of linear atrophoderma of Moulin were described in the literature. There is not a proven effective treatment of this dermatosis. High dose penicillin, topical corticosteroids, heparin, and oral potassium aminobenzoate have been used but found to be uneffective. To our knowledge, this is the first case of extensive linear atrophoderma of Moulin treated with methotrexate.

Long-pulsed Nd:YAG laser in the treatment of facial hypertrichosis during topical minoxidil therapy.

Hypertrichosis is a well-recognized adverse effect of therapy with either oral or topical minoxidil. We report a case of fronto-temporal hypertrichosis occurring in an 8-year-old girl treated for patchy alopecia areata of the frontal area of the scalp with 2% minoxidil solution. After failure of 5-months minoxidil-discontinuation, hair removal with Nd:YAG laser (1064 nm line) (Smartepil II, Deka) was tested leading to complete resolution within 2 sessions.

Should we continue to indicate meglumine antimoniate as first-line treatment for cutaneous leishmaniasis in Tunisia.

Meglumine antimoniate compounds have been the mainstay of treatment for cutaneous leishmaniasis (CL) for decades. We propose to evaluate the place of these drugs in this indication in Tunisia. We retrospectively reviewed medical records of 67 patients treated for (CL) using meglumine antimoniate at a dose of 20 mg/kg/day for 15 day from 1998 to 2010. Clinical and laboratory data, tolerance, and outcome were precised. Side effects were recorded in 17 among 67 patients (25%). The average age was 44.4 years (2-86 years). Antimony intolerance events occurred in 11 patients, stibio-intoxication events in nine cases, and the both type of antimony adverse effects were observed in three patients. Fever was the most frequent complication of antimony intolerance (five cases), followed by cough (three cases), rash (two cases), injection site erythema (two cases), musculoskeletal pain (one case), asthenia (one case), and vomiting (one case). Signs of stibio-intoxication were asymptomatic elevation of amylase level (four cases), hepatic cytolysis (three cases), hematologic toxicity (three cases), and acute toxic kidney failure (one case). Meglumine antimoniate was stopped in 13 cases. Systemic administration of pentavalent antimonials in the treatment of CL has been associated with severe adverse effects. CL observed in Tunisia is a self-healing dermatosis that never induces sequela; therefore, other therapies such as topical treatment or cryotherapy should be considered.

Radiotherapy-induced pemphigus vulgaris with autoantibodies targeting a 110 kDa epidermal antigen.

BACKGROUND: Pemphigus is an autoimmune intraepidermal blistering disease mediated by autoantibodies targeting desmosomes. It can be induced by many triggers, such as ionizing radiation. METHODS: We report a case of radiotherapy-induced pemphigus (RIP) with a review of the published cases in the English and French literature. RESULTS: A 61-year old man was diagnosed to have epidermoid carcinoma of the piriform sinus and then received a 70 Gy radiation therapy. One month after the treatment completion, multiple blisters and erosions occurred initially on the site of irradiation, then in other skin areas. Histological examination showed an intraepidermal blister with acantholysis and necrosis of individual keratinocytes. Direct immunofluorescence and indirect immunofluorescence were typical of pemphigus. Immunoblot revealed antibodies reacting with a 110 kDa antigen. This feature was consistent with the diagnosis of RIP. Less than 20 cases of RIP have been reported previously. Mean age at diagnosis was 64.2 years, and there is a slight female preponderance. RIP occurred, in most cases, initially within the area of irradiation. CONCLUSION: Our patient showed some distinctive findings never reported previously in RIP: a histological focal keratinocyte necrosis, and the presence of autoantibodies reacting with a 110 kDa keratinocytic protein in immunoblot analysis. Because of a different prognosis, it is important to differentiate RIP and paraneoplastic pemphigus (PNP), although cases of ionizing radiation-induced PNP had also been described. As in our patient, RIP seems to respond well to systemic corticosteroids and immunosuppressive therapy, which induce remission within a few months.

[Basal cell carcinoma of unusual site]. / Carcinome basocellulaire de siège inhabituel.

BACKGROUND: Labial mucosa is an atypical site of basal cell carcinoma. The involvement of the vermilion lip, devoid of hair follicles and sweat glands, contrasts with the concept of its origin from pilar structures. We report a case of basal cell carcinoma developed on the vermilion upper lip. CASE REPORT: A 49-year-old woman, presented with an asymptomatic, 1-cm-diameter, erythematous, telangiectatic and crusted nodule on the upper lip evolving for 9 months and having once interested the vermilion border. There were no cervical lymph nodes. Diagnosis of infiltrative basal cell carcinoma was made by histological study, which showed a tumoral proliferation of epithelial basal cells infiltrating the dermis with perineural and muscular infiltration. DISCUSSION: Our report illustrates a rare but not exceptional site of basal cell carcinoma. The nodule, initially confined to the vermilion border, has then developed onto the mucosal and the cutaneous areas. Histopathological study revealed, as previously reported, infiltarative features. Basal cell carcinoma of the lip should be rapidly managed since its invasion to deeper structures occurs early.