Dextran Carrier Macromolecules for Colon-specific Delivery of 5-Aminosalicylic Acid.

Present manuscript describes the sustained and targeted delivery of 5-aminosalicylic acid to the distal ileum and proximal colon, using dextran (40 kDa) as a carrier for targeting 5-aminosalicylic acid at the colonic site by attaching p-aminobenzoic acid and benzoic acid as linkers. Prepared conjugate were characterized by UV, HPLC, FT-IR, and (1)H NMR. The degree of substitution was estimated by complete hydrolysis of conjugates in borate buffer and in vitro hydrolysis study of conjugates was performed in different biological media. It was observed that 5-aminosalicylic acid alone have produced high incidence of gastric ulcer with high ulcer index whereas lower ulcer index was found for the dextran conjugates of 5-aminosalicylic acid. The release pattern of conjugates in 3% w/v rat caecal content was confirmed the colon specificity of 5-aminosalicylic acid conjugates.

Hydrolytic Degradation Profile and RP-HPLC Estimation of Cilostazol in Tablet Dosage Form.

A simple, selective, precise and stability-indicating high-performance liquid-chromatographic method of analysis of cilostazol in pharmaceutical dosage form was developed and validated. The solvent system consisted of 10 mM phosphate buffer (pH 6.0):acetonitrile:methanol (20:40:40). Retention time of cilostazol in C18 column was 5.7 +/- 0.1 min at the flow rate 1.3 ml/min. Cilostazol was detected at 248 nm at room temperature. The linear regression analysis data for the calibration plots showed good linear relationship with correlation coefficient value, r( 2) =0.9998 in the concentration range 100-3200 ng/ml with slope 43.45 intercept 156.75. The method was validated for linearity, range, accuracy, precision and specificity. Cilostazol was determined in tablet dosage form in range of 99.58-100.67% with 0.4600 standard deviation. Stress studies were conducted in acid and alkali hydrolysis with gradual increasing concentration. Cilostazol was found to be stable in various concentrations of acidic and alkaline.

Concurrent Estimation of Clopidogrel Bisulfate and Aspirin in Tablets by Validated RP-HPLC Method.

A simple, rapid, precise RP-HPLC method was developed for simultaneous estimation of aspirin and clopidogrel bisulphate in tablet dosage form used in the treatment of cardiovascular diseases. To achieve the maximum resolution, acetonitrile:50 mM potassium dihydrogen phosphate buffer:methanol, solution pH adjusted to 3, in the ratio 50:30:20; v/v was selected as mobile phase. This mixture was found to be appropriate allowing good separation of both the components at a flow rate of 1.5 ml/min and detection wavelength 240 nm. In these conditions clopidogrel bisulfate and aspirin were eluated at the 7.47 and 2.2 min. The linearity was found in the concentration range 1.5-7.5 and 3.5-15.0 µg/ml, respectively. All the analytical validation parameters were determined and found with in the limit as per ICH guideline, which indicates the validity of method.

Effect of antimalarial drugs on erythrocyte agglutination by lectins.

The study reports on the effect of 6 antimalarial drugs on red cell agglutination by Erythrina lithosperma. Phaseolus vulgaris and Ulex europaeus lectins. Some drugs inhibited agglutination while others potentiated it. Possible causes have been discussed.

Functional eustachian tuboplasty: a new surgical technique.

Until recently, there was no answer for the "physiologic" stenosis of the Eustachian tube (occurring in 20% of all cases of tubal occlusion). We describe a newly devised surgical procedure-tensor palati tendon "strengthening"-for the management of physiologic stenosis of the Eustachian tube. After the initial dissection of 20 cadavers, the basic surgical procedure was worked out. Then, the experimental study was conducted in four dogs to evaluate the effects of this new operation on the Eustachian tube functions as well as on the soft palate movements. Finally, four patients with physiologic tubal stenosis were treated successfully. The follow-up period ranged from 16 to 20 months. Strict selection of patients is encouraged.

Studies on the Dd antigen-antibody system. II. Antigen Dd reactivity in some north indian populations.

The frequency of antigen Dd-reactors has been recorded in Muslims and Buddhists from Ladakh, in Rana Tharus from Uttar Pradesh and in two samples of largely Jat Sikh origin from Punjab, all in India. The results show a wide range of variation, from 0% in the Rana Tharus to 25% in the Punjabi blood donors, of incidence of antigen Dd-reactivity in these populations.

The distribution of LH types in some North Indian populations.

Results of a twin study on the distribution of LH (a new red blood cell membrane specificity) and ABO blood types have been reported among the Jat Sikh, Khatri, Ramdasia and a sample of mixed Punjabis from North India. The LH types are distributed bimodally, albeit with varying frequencies, in individuals with blood types other than O, in whom only the LH+ type occurred. The results suggest that the LH system could be usefully employed in population genetic studies, particularly in association with the ABO system.

Genetics of the LH red blood cell membrane specificity.

A lectin obtained from seeds of Erythrina lithosperma detects a new specificity, called LH, on the human red blood cell membrane. Family investigations show conclusively that the specificity is under autosomal genetic control, with the gene determining the LH- type being dominant over its allele for the LH+ type.

Antigen Dd reactivity in selected diseases.

The distribution of detectable antibodies against antigen Dd has been studied in rheumatoid arthritis, goitre, nephrotic syndrome, cirrhosis, gastrointestinal tract diseases, neurological diseases, liver and gall bladder diseases, breast cancer, respiratory diseases and cardiovascular diseases. Except in rheumatoid arthritis, breast cancer and nephrotic syndrome, where the incidence of antigen Dd-reactivity did not differ much from that in the control group, in all other disease it was significantly lower.

The distribution of AB0 and LH blood groups in some north Indian populations.

The distribution of AB0 and LH blood groups among five Punjabi populations from North India (Jat Sikh, Bania, Brahmin, Sikh Khatri and Hindu Khatri) is reported. Significant differences have been found in many cases regarding the distribution of AB0 and LH systems, especially between Sikh Khatris and Hindu Khatris, who are usually pooled for population genetic studies.

Haptoglobin polymorphism in the Ladakhi population.

Haptoglobin polymorphism has been studied in 148 Ladakhis -- a Mongoloid population inhabiting the northern-most region of India. With a frequency of 0.270 for the allele Hp1 the Ladakhis compare favourably with other Mongoloid populations.

The LH red blood cell membrane specificity in three South Indian populations.

187 Gampasati Kamma, 120 Pokanati Reddi and 98 Tangala Mala from Andhra Pradesh were examined for the LH red blood cell membrane specificity. Significant differences were observed in regard to the distribution of LH specificity in all the three populations. The results have been compared with those on some North Indian populations.

Distribution of some genetic traits in three populations from Punjab, North India.

Three population groups, viz. Jat Sikh (192), Khatri (105) and Balmiki (108) were screened for haptoglobins, transferrins, Australia antigen, antigen Dd-reactivity and the ABO blood groups. The frequencies in Jat Sikhs, Khatris and Balmikis were 0.232, 0.186 and 0.140 respectively for Hp1 allele, 0.52%, 0.95% and 1.85% for Australia antigen, and 17.30%, 21.90% and 19.44% for antibodies against antigen Dd. The transferrins were all of type Tf C. The frequencies for the alleles A, B and O of the ABO system were 0.216, 0.239 and 0.545 in Jat Sikhs, 0.238, 0.320 and 0.442 in Khatris, and 0.196, 0.274 and 0.530 in Balmikis. Our tests showed these populations to be in Hardy-Weinberg equilibrium.

Serum protein polymorphisms in goitre.

Serum albumin, ceruloplasmin, transferrin and haptoglobin were studied in 50 patients with both toxic and non-toxic forms of goitre. Albumin was monomorphic in all cases and its amount was substantially lower than normal in two patients. Ceruloplasmin was both qualitatively and quantitatively normal in all patients. No genetic variants of transferrin were encountered but 22% of the patients had this protein, at levels barely detectable by electrophoretic means. Such cases of hypotransferrinaemia occurred oftener in patients with the toxic form of goitre than in those with the non-toxic one. The distribution of haptoglobin types in patients was much the same as in the control blood donors. However, the patients had a greater incidence of ahaptoglobinaemia.

Some biochemical polymorphisms in members of the Gaddi tribe of Himachal Pradesh.

This study was carried out among members of the Gaddi tribe of Himachal Pradesh in north India. The genetic traits reported here include ABO blood groups, haptoglobin, transferrin, albumin, Gc, Australia antigen and antigen Dd. The frequencies of genes p, q and r for the ABO system were 0.212, 0.290 and 0.428. The Hp1 allele frequency (0.331) was markedly higher and that of Gc1 (0.700) somewhat lower than in most north Indian populations. The incidence of Australia antigen was 1.25%. There were no antigen Dd reactors.