Dentin permeability of the apical third in different groups of teeth

This ex vivo study evaluated dentin permeability of the root canal in the apical third of different human groups of teeth. Eighty teeth were used, 8 from each dental group: maxillary and mandibular central incisors, lateral incisors and canines, maxillary first premolars (buccal and palatal roots), mandibular first premolars, and maxillary and mandibular second premolars, totalizing 88 roots that were distributed in 11 groups. The root canals were instrumented, irrigated with 1 percent NaOCl and 15 percent EDTA. Roots were immersed in 10 percent copper sulfate for 30 min and then in 1 percent rubeanic acid alcohol solution for the same period; this chemical reaction reveals dentin permeability by the formation of copper rubeanate, which is a dark-colored compound. Semi-serial 100-µm-thick cross-sections were obtained from the apical third of the roots. Five sections of each apical third were washed, dehydrated, cleared and mounted on glass slides for examination under optical microscopy. The percentage of copper ion infiltration and the amount of tubular dentin were quantified by morphometric analysis. The penetration of copper ions in the apical third ranged from 4.60 to 16.66 percent. The mandibular central and lateral incisors presented the highest dentin permeability (16.66 percent), while the maxillary canines and mandibular second and first premolars presented the lowest dentin permeability (4.60 percent, 4.80 percent and 5.71 percent, respectively; p<0.001). The other teeth presented intermediate permeability. In conclusion, dye penetration into dentin tubules at the apical region is strongly dependent on the group of teeth evaluated.

Este estudo ex vivo avaliou a permeabilidade da dentina do canal radicular do terço apical de diferentes grupos de dentes humanos. Foram utilizados 80 dentes, sendo 8 de cada grupo dental superior e inferior: incisivos centrais, incisivos laterais, caninos, primeiros pré-molares superiores (raízes vestibulares e palatinas), primeiros pré-molares inferiores, segundos pré-molares superiores e inferiores, totalizando 88 raízes, as quais foram distribuídas em 11 grupos. Os canais foram instrumentados, irrigados com NaOCl a 1 por cento e EDTA a 15 por cento. As raízes foram imersas em sulfato de cobre a 10 por cento por 30 min e acido rubeânico a 1 por cento pelo mesmo período. Esta reação química revela a permeabilidade da dentina por meio da formação de um complexo escurecido denominado rubeanato de cobre. Hemi-secções de 100 µm de espessura foram obtidas do terço apical da raiz. Cinco secções do terço apical foram lavadas, desidratadas, diafanizadas e montadas em lâminas para análise em microscopia óptica. A porcentagem de infiltração de íons cobre e a quantidade de dentina tubular foram quantificadas por meio de análise morfométrica. A penetração de íons cobre no terço apical da raiz variou de 4,60 por cento a 16,66 por cento. Os incisivos centrais e laterais apresentaram a maior permeabilidade dentinária (16,66 por cento), e os caninos superiores e segundos e primeiros pré-molares inferiores as menores (4,60 por cento, 4,80 por cento e 5,71 por cento, respectivamente; p<0,001). Os outros dentes apresentaram permeabilidade intermediaria. Conclui-se que a penetração de corante nos túbulos dentinários da região apical é extremamente dependente do grupo de dentes avaliado.

XDR tuberculosis: a report from the New Delhi Tuberculosis centre, India

During the 6 years from 2001 to 2006, a total of 18,443 M. tuberculosis isolates were processed for drug sensitivity testing. Of those, 9614 [52.12%] were found to be multidrug resistant. A total of 86 [0.89%] cases met the criteria of XDR among the MDR-TB cases. Year-wise detection of these XDR cases is given in Table I. A consistent decline was observed in the incidence of reported cases of XDR over the years right from the year 2001. These 86 cases were reported from 7 states with the largest number from Delhi [49] followed by neighbouring Rajasthan [10], Haryana [9], Uttar Pradesh [8], Uttaranchal [5], Punjab [4] and Madhya Pradesh [1]. Of those 86 cases, only 5 patients were females and rest were males. A total of 53 out of 86 [61.6%] of the isolated resistant strains were resistant to more than 4 classes of drugs indicating severity of resistance

Outcome of multi-drug resistant tuberculosis cases treated by individualized regimens at a tertiary level clinic.

AIM: To determine the clinical, radiological and drug resistance profile as well as the factors associated with treatment outcome of Multi-Drug Resistant Tuberculosis (MDR-TB). MATERIAL AND METHODS: All newly diagnosed patients with pulmonary MDR-TB from August 2002 to December 2004 enrolled at New Delhi Tuberculosis Centre, were included in the study. They were followed up clinically, radiologically and bacteriologically by sputum smear, culture and Drug Susceptibility Testing (DST) at regular intervals. According to their DST pattern and previous history of Anti-Tubercular Treatment (ATT), individualized treatment regimens were tailored for each patient. RESULTS: Out of total 27 bacteriologically proven cases of MDR-TB included in this study, 19 were males (mean age and weight 38.5 years and 52.6 kgs, respectively) and eight females (mean age and weight 34.3 years and 40.7 kgs, respectively). A majority (18) were residents of Delhi and the rest hailed from different parts of North India. All of them had a history of previous treatment ranging from six to 34 months. Cavity on chest X-rays was seen in 81%, while 44% showed extensive involvement. The patients received at least four "second line drugs" during their treatment with a mean of 6.2 anti-tubercular drugs during their intensive phase. Of the 27 patients, 13 were cured, 10 defaulted, one died, one is still on treatment and two were referred for surgery. Radiological improvement was observed in two third of cases and chest X-ray of two patients showed a complete resolution. Six predictors were identified for successful outcome of MDR-TB. They include weight gain at six months, culture conversion, radiological improvement during treatment, disease with M. tuberculosis strains exhibiting resistance to less than or up to three anti-tubercular drugs, use of less than or up to three second line drugs in treatment and no change of regimen during treatment. CONCLUSION: Default from treatment was observed to be a major challenge in the treatment of MDR-TB due to long duration and expense of ATT.

Spectrophotometric determination of certain drugs using ammonium cerium [IV] sulfate and p-dimethylaminobenzaldehyde

A spectrophotometric method for the determination of acetylcysteine, captopril carbimazole propylthiouracel and thiopental sodium is described. The method was based on the oxidation of the studied drugs with excess ammonium cerium [IV] sulfate. Followed by measuring the excess unreacted ammonium cerium [IV] sulfate, through reaction with p-DMAB into the corresponding p-dimethylaminobenzoquinone, which has a red colour can be measured at 464 nm. The decrease in the absorption intensity at 464 nm caused by the presence of the investigated drugs is directly proportional to their concentration. Investigations were carried out to study all variables and a validation study for the proposed procedure according to USP 2002 was also performed. Beer's law was obeyed in the range of 1-40 micro.g/ml. The detection limit ranged from 0.22-1.22 micro g/ml, while the quantitation limit ranged from 0.73-4.06 micro g/ml. The proposed method was successfully applied for the analysis of the studied drugs in pharmaceutical preparations with good recoveries in the range of 98.12-100.02%. Results were compared with those obtained from the pharmacopoeial or reported methods

Oxidized diphenylamine as a spectrophotometrec reagent for the determination of some pharmaceutical thiols and thioamides

Oxidized diphenylamine is newly utilized as a redox spectrophotometric reagent for the determination of six pharmaceutically important thiol and thioamide drugs named: acetylcystiene, captopril, carbimazole, propylthiouracil, thiopental sodium, and tiopronin. The method is based on measurement of the decrease in absorption intensity of the oxidized diphenylamine [diphenylbenzidine violet, lambda max = 580 nm] reagent as a result of the reduction effect of the analysed drugs This reagent was instantaneously prepared by the oxidation of diphenylamine using ferric sulphate in sulphuric acid medium. The molar ratio of the chromogen reagent was determined to be 2:1; diphenylamine: iron [III]. The decrease in colour intensity was found to be quantitatively dependent on drug concentration. Experimental variables including reagent concentration, acid type and concentration, dilution solvent, reaction time, temperature and stability were studied and optimized. Validation parameters including linearity range, detection and quantitation limits, precision, selectivity and robustness were evaluated. The proposed method was found to be simple, sensitive and accurate one indicated by the studied validation parameters. Good recoveries [98.0 +/- 0.14 - 100%, +/- 0.98] were obtained by the suggested method and it was applied for the determination of the studied drugs in many pharmaceutical dosage forms available in the local market. Good agreement, indicated by acceptable t- and F- tests, was found between results obtained by the suggested method and those obtained by the reported or pharmacopoeial methods

Terapêutica da hanseníase: situaçäo atual / Therapeutic of leprosy: current situation

O autor enfatiza o tratamento como um dos esteios do controle da hanseníase. Faz revisäo histórica das drogas utilizadas, do mecanismo de açäo, das doses recomendadas e dos principais efeitos colaterais. Ressalta a importância da poliquimioterapia, porposta pela OMS, usando a sulfona, a rifampicina, a clofazimina e a etionamida. Revê o tratamento das reaçöes, oproblema da resistência medicamentosa e o conceito de bacilos persistentes. Apresenta a situaçäo atual da imunoterapia e a esperança depositada em novos fármacos - derivados da quinolona e as ansamicinas. Cita dados promissores das experiências com MDT, supervisionadas pela OMS, e a possibilidade de erradicar ou minimizar o problema da hanseníase nos países onde a doença é endêmica.

Histología y técnica de PAS y acido rubeánico en biopsias endometriales de usuarias de T de cobre / Histology and PAS and rubeanic acid technics in endometrial biopsies of TCU device users

El presente trabajo se realizó en el Centro Médico Materno-Infantil y Planificación Familiar de El Augustino, Lima. Se realizó el estudio de 41 biopsias endometriales de mujeres usuarias de "T" de cobre (200mm2), entre 19 y 35 años de edad; de probada fertilidad y clínicamente sanas, con 1 mes a 2 años y 10 meses de use del dispositivo; que acudían a su control periódico por usar DIU. En un 60 por ciento de las biopsias endometriales del grupo de mujeres con T de Cobre se encontró atraso en la maduración y/o maduración irregular del endometrio. Se encontró que los cambios en la maduración del endometrio, no tenían relación con el tiempo de uso del dispositivo. En el 90 por ciento de las biopsias endometriales del grupo de mujeres con T de cobre, se encuentra reacción inflamatoria no específica, predominantemente aguda y crónica de grado moderado; sin relación con el tiempo de uso del dispositivo. Las mayores alteraciones estructurales del endometrio se encontraron en la zona de la huella del DIU. La determinación histoquímica del cobre por el método del ácido rubéanico, fue más elevado (70 por ciento) en las biopsias fijadas directamente en ácido rubéanico, que entre Kas biopsias fijadas en formalina y despúes tratadas con ácido rubéanico. Entre los casos que se encontró positividad para el cobre no se encontró relación con el tiempo de uso del dispositivo. El conjunto de las alteraciones antes descritas parecerían tener un rol importante en la capacidad anticonceptiva de la T de Cobre