Haemorrheologicals: a new approach in the treatment of recurrent aphthous ulcer.

Oral ulcers may have a great many causes. Aphthous stomatitis or Recurrent Aphthous Ulceration (RAU) is an extremely common disorder of the oral cavity. The majority of chronic oral ulcers are accounted for by major aphthous ulcers. The diagnosis of RAU is made on clinical grounds and through exclusion criteria .Here we present a case of RAU treated with a different drug regime.

A study of changes in pulmonary function with advancing age and the effect of smoking in males of North Kerala.

As the life expectancy is rising virtually in all proportions throughout the world, awareness of the basic changes in respiratory physiology associated with aging and their clinical implication is important for clinicians. Similarly Chronic obstructive pulmonary disease has emerged as a major health condition worldwide and cigarette smoking has been clearly documented as a risk factor for it. We made an attempt to assess the changes in the pulmonary function with age and also to assess the effect of smoking in males of 18-85 years from North Kerala . The pulmonary function tests were assessed on a computerized spirometer in 247 male subjects, out of which 127 were nonsmokers and 121 were smokers . The results showed a strong negative correlation between various age groups indicating a statistically significant decrease in all pulmonary function parameters as age increases(p<0.01). All the pulmonary function parameters were also significantly decreased in smokers when compared to nonsmokers of the same age groups (p<0.01). The percentage of smokers having airflow limitation (33.1%) was more than 5 times that of the nonsmokers (5.6%). Thus by spirometry airflow limitation can be measured at an early stage so that subsequent morbidity can be minimized by life style changes and more targeted smoking cessation programmes.

Genotype-phenotype correlation analysis in retinoblastoma patients from India.

BACKGROUND: Genetic analysis has a beneficial impact on retinoblastoma management enabling definite risk assessment. However, information regarding genotype-phenotype correlation in retinoblastoma is limited. AIM: To analyze the retinoblastoma susceptibility gene for mutations in retinoblastoma patients and correlate the genotypes the phenotypes. METHODOLOGY: Eleven retinoblastoma patients, who underwent molecular genetic studies were classified into high, moderate or low disease severity groups based on phenotype. RESULTS: Seven patients had high disease severity and four moderate disease severity. Eleven truncating mutations were detected; six were in the N-terminus region of the retinoblastoma protein and two in the A/B pocket (p=0.03). CONCLUSIONS: No significant association between mutation type and disease severity could be established in the present study. However a positive correlation between location of the mutations in certain domains of the retinoblastoma protein and disease severity was observed. To the best of our knowledge this is the first genotype-phenotype correlation study in retinoblastoma patients from India.

Retinoblastoma: a diagnostic model for India.

PURPOSE: Molecular genetic diagnostics for retinoblastoma are prerequisite for accurate risk prediction and effective management. Developing a retinoblastoma diagnostic model to establish a flow for laboratory tests is thus a necessity for tertiary ophthalmic institutions. An efficient diagnostic model could reduce the overall health care costs, redirect the resources to the high risk group and also avoid unnecessary worry for families. To the best of our knowledge there has hitherto been no comprehensive diagnostic model for retinoblastoma implemented in any institution in India. METHODS AND DISCUSSION: The diagnostic model demonstrates the logical and practical flow of various genetics tests like karyotyping, loss of heterozygosity analysis, molecular deletion, linkage analysis (familial cases), mutation screening of -CGA exons first and then non-CGA exons, methylation screening of RB1 and essential promoter regions screening in a laboratory. Conclusions: The diagnostic model proposed offers acomprehensive methodology to identify the causative two-hits for retinoblastomas that could be used while genetic counseling families. This model is applicable in tertiary hospitals in India and neighboring countries, which have the highest incidence of retinoblastoma and fertility rates in the world. We suggest that this diagnostic model could also be applied with modification for other cancers.

CGA codons multiplex PCR in rapid diagnosis of retinoblastoma.

Background: Multiplex polymerase chain reaction allows amplification of multiple target sequences of a genome under identical conditions in a single tube. This "one-shot" polymerase chain reaction detection is time and cost effective when large or multiple genes, with many target fragments are investigated. This is applicable for retinoblastoma susceptibility gene having 27 exons with recurrent mutations reported at most of the 12 CGA codons. Materials and Methods: Multiplex polymerase chain reaction assay for the amplification of 12 CGA codons, which constitutes about 50 % of retinoblastoma susceptibility gene mutations has been designed. The time and cost (includes only reagent cost) involved in both multiplex and uniplex polymerase chain reaction was also calculated. Results: Twelve CGA codons were multiplexed in 5 instead of 12 uniplex polymerase chain reactions, which took 36 hours and 9.78 US$ whereas multiplex polymerase chain reaction took 15 hours and 6.88 US$. Multiplex polymerase chain reaction method saved 58.3% of time and 29.6% of cost over uniplex polymerase chain reaction. Conclusion: Saving time by more than half and cost by nearly a third would help clinicians and geneticists while counseling retinoblastoma patients.

Karyotyping in retinoblastoma--a statistical approach.

PURPOSE: Karyotype analysis in hereditary retinoblastoma is considered to be of marginal value in risk prediction due to uncertainties in the assessment of 13q14 deletions. However, it is a low cost genetic test for retinoblastoma in developing countries. In the present study, the results of karyotype analysis were refined by a statistical method to overcome limitations. METHODS: Karyotype analysis was performed by trypsin-Giemsa banding and naked eye karyotyping for 33 bilateral, 25 unilateral and one regressed retinoblastoma patients. The percentage of metaphases with 13q14 deletions in each case was plotted on a scatter diagram. Normalization of the data was achieved by log transformation and the results were statistically analyzed by one-sample 't' test using SPSS version 9.0. RESULTS: Seven samples had 13q14 deletion percentages above the cutoff value. One-sample 't' test showed significance (p< 0.001). By this method, two unilateral and five bilateral patients had 13q14 deletions, constituting 11.8 % of cases. CONCLUSION: For accuracy, statistical analysis should be considered as an adjunct in karyotyping.

Molecular-genetic analysis of two cases with retinoblastoma: benefits for disease management.

Effective counselling and management of retinoblastoma families using genetic information is presently practised in many parts of the world. We studied histopathological, chromosomal and molecular-genetic data of two retinoblastoma patients from India. The two patients, one with bilateral and the other with unilateral retinoblastoma, underwent complete ophthalmic examination, cytogenetic study, retinoblastoma gene (RB1) mutational analysis and RB1 promoter region methylation screening. In the bilateral retinoblastoma patient deletion of chromosome region 13q14 in peripheral blood lymphocytes and a hemizygous novel 8-bp deletion in exon 4 of RB1 in tumour sample were observed. In the unilaterally affected patient CGA to TGA transition protein truncation mutations were observed in exons 8 and 14 of RB1.

RPE65 gene: multiplex PCR and mutation screening in patients from India with retinal degenerative diseases.

We used multiplex PCR follwed by sequencing to screen for mutations in the 14 exons of the RPE65 gene in early-childhood-onset autosomal recessive retinitis pigmentosa (arRP) and Leber's congenital amaurosis (LCA) patients. The RPE65 protein is believed to play an important role in the metabolism of vitamin A in the visual cycle and mutations identified in the gene could have implications for vitamin A-based therapeutic intervention. We were able to identify a homozygous mutation (AAT --> AAG) in exon 9 in an arRP patient and a heterozygous missense transversion (AAT --> AAG) also in exon 9 of an LCA patient. We also identified a polymorphism in exon 10 (GAG --> GAA) in an arRP as well as an LCA patient. Mutation screening would be greatly facilitated by multiplex PCR which could cut down costs, labour and time involved. The nucleotide changes observed in this study could be de novo. Though a larger study has been undertaken, from the preliminary results it appears that in India the RPE65 gene seems to be less involved in causation of LCA.