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S B Nair

Publications and source records attributed to S B Nair.

10 recordsLinked to original sources
PubMed2006

A crypto-Dravidian origin for the nontribal communities of South India based on human leukocyte antigen class I diversity.

The Dravidian communities are considered to be the original inhabitants of India, now restricted to South India. The southern most state, Kerala, is socio-culturally stratified into Hindus, Muslims and Christians on the basis of religion. The origin of these religious communities in Kerala is considered to be unique in comparison with that in other parts of the country. These communities were later influenced by the hierarchical caste structure established by the Hindu Brahmins. In the present study, we compared six nontribal (Namboothiri, Nair, Ezhava, Pulaya, Malabar Muslim and Syrian Christian) communities belonging to the major religious groups in Kerala (Hindu, Muslim and Christian) based on the human leukocyte antigen (HLA)-A, -B and -C diversity. Our aim was to understand the genomic substructuring associated with the changing social scenario in various caste and religious groups and compare it with the Dravidian tribal and other world populations. The present study reveals that the HLA diversity of the Dravidian communities is very distinct from that in the other world populations. It is obvious that the nontribal communities of Kerala display a greater Dravidian influence, but traces of genetic admixture with the Mediterranean, western European, central Asian and East Asian populations can be observed. This characterizes the crypto-Dravidian features of the nontribal communities of Kerala. Demic diffusion of the local progressive communities with the migrant communities may have given rise to crypto-Dravidian features among the nontribal communities of Kerala.

Alleles↗
PubMed2004

Nasopharyngeal pH monitoring in chronic sinusitis patients using a novel four channel probe.

OBJECTIVE: To determine the prevalence of acid reflux into the nasopharynx in patients with chronic sinusitis. STUDY DESIGN: Prospective study of patients presenting to a specialist rhinology practice with chronic sinusitis. METHODS: Forty patients with chronic sinusitis underwent ambulatory 24 hour pH testing. The mean age of the patients was 56.3 years (25 Female, 15 Male). The studies were performed using a specially developed bifurcated 4 channel pH probe, incorporating 2 circumferential sensors positioned at the naso- and hypo-pharynx, and 2 unidirectional sensors positioned at the proximal and distal esophagus. RESULTS: The circumferential band sensors yielded a stable recording largely free of artefact allowing meaningful recordings to be obtained from thirty-seven patients. Twelve patients (32.4%) were diagnosed with gastroesophageal reflux. A total of 809 reflux episodes were recorded. Of these, 596 (73.7%) reached the distal esophagus, with 187 (23.1%) and 24 (3.0%) reaching the proximal esophagus and hypopharynx respectively. Only 2 episodes (0.2%) were recorded in the nasopharynx. This occurred in 2 of 37 patients (5%). CONCLUSIONS: Acid reflux into the nasopharynx is a rare event in patients with chronic sinusitis even though a significant proportion (32.4%) have abnormal 24 hour pH studies. It is likely that alternative mechanisms other than direct acid contact are involved in the pathogenesis of chronic sinusitis.

Adult↗
PubMed2004

HLA-B and HLA-C alleles and haplotypes in the Dravidian tribal populations of southern India.

The Dravidians are believed to be the earliest inhabitants of India. Their subsequent migration and admixture with invading racial groups has been of scientific interest for population geneticists. In the present study, seven highly endogamous and extremely isolated colonies of Dravidian tribal populations (n = 105) from Kerala in South India were analysed and compared with random non-tribal Dravidian (RND) samples (n = 78) of southern India using the polymerase chain reaction with sequence-specific primer method for HLA-B and HLA-C typing. The tribal group comprises Adiya, Kanikkar, Kattunaikka, Kuruma, Kurichiya, Malapandaram and Paniya, while the RND group includes Malayalam-speaking individuals from various non-tribal castes of Kerala selected randomly. Some of the most frequent HLA-B alleles in the RND population were similar to the North Indian population and included B*07, B*61 (B*40), B*44, B*51, B*35 and B*52. Although B*61 was the most frequent allele in our total study population, the frequency fluctuated in individual populations. HLA-Cw*14 was one of the most frequent alleles while HLA-Cw*17 was totally absent in all populations studied. The haplotype B*61-Cw*14 was present in all the study groups except in Kurichiya, and the haplotype B*51-Cw*14 was only absent in Kattunaikka. Phylogenetic tree and correspondence analysis indicate that all the Dravidian tribal communities group together as a separate cluster, while the RND group of individuals from South India lie close to the North Indian population. This suggests that the RND population of South India might have a crypto-Dravidian origin, while the smaller Dravidian tribal communities have a distinct Dravidian origin.

Alleles↗
PubMed2001

Glanzmann's thrombasthenia.

Glanzmann's thrombasthenia (GT) is an uncommon cause of bleeding in children. We diagnosed two siblings as having GT on the basis of flow cytometric studies. Both had cutaneous bleedings and epistaxis since early childhood. Hematological investigations revealed prolonged bleeding time and a normal platelet count. Both the patients had absence of aggregation of platelets with the agonist adenosine diphosphate. Absence of the GPIIb/IIIa receptor was confirmed by flow cytometry. A short review of the disorder is presented.

Child, Preschool↗
PubMed2000

Caesarean section delivery in Kerala, India: evidence from a National Family Health Survey.

Ensuring safe pregnancy and motherhood occupies a pivotal role and has been considered as one of the key issues in the framework of reproductive and child health programmes. Evidence from research studies indicate that there is a growing tendency for caesarean section deliveries especially during complications confronted at the time of pregnancy and delivery. The present study focuses on the demographic, antenatal care, spatial and socio-economic variables associated with caesarean section delivery in Kerala, India. The data from the National Family Health Survey has been utilised for this purpose. The results from logistic regression models indicate that maternal age, birth order, current age, births in health institutions and spatial differences were significantly associated with caesarean section deliveries in Kerala. The older cohorts of mothers were found at higher risk to have caesarean section when compared to their younger counterparts. When controlled for demographic variables, the odds for caesarean section was about 1.7 times more likely to occur in private health institutions. The inclusion of spatial and socio-economic variables has neither influenced the demographic and antenatal care variables nor showed any significant association with caesarean section delivery in the state. The present study calls for that a detailed investigation on behavioural aspects of both the physician and the patient with regard to type of delivery in the state. Information related to pregnancy and health related aspects needs to be monitored more accurately, both in the public and private hospitals, to understand the determinants associated with caesarean section.

Cesarean Section↗
PubMed2000

A retrospective analysis of high resolution computed tomography in the assessment of cochlear implant patients.

High resolution computed tomography (HRCT) of the temporal bone is performed routinely in the preoperative evaluation for cochlear implantation. The largest multicentre retrospective analysis of data was undertaken to compare the findings on HRCT with the surgical findings in an attempt to determine the accuracy of HRCT. Of the 1009 patients referred, 525 were scanned of whom 335 were implanted. As part of this study we were also able to identify both radiological and non-radiological reasons for rejection of patients for cochlear implantation. the commonest cause being adequate residual hearing. The accuracy of HRCT in predicting cochlear ossification was 94.6%, with a 100% specificity and a 71%, sensitivity. Meningitis was the leading cause of cochlear ossification (44%). We conclude from this extensive multicentre study of both adult and paediatric patients that HRCT is accurate in predicting cochlear abnormality. In post-meningitic patients magnetic resonance imaging (MRI) may be a useful additional investigation.

Adult↗
PubMed1999

Metastatic melanoma of the tonsil.

Metastasis to the tonsils from malignant melanoma is rare. This paper describes one such case in a woman with synchronous breast adenocarcinoma and cutaneous malignant melanoma who had a most unusual clinical course.

Aged↗
PubMed1999

Trends in the UK contribution to the otolaryngological literature.

Ten leading otolaryngological journals were reviewed with a view to detecting the UK contribution to the ENT literature from 1985 to 1994. From a total number of 12,293 publications studied 2414 (19.6%) papers were found to originate from British and Northern Irish otolaryngological departments, with the proportion of UK papers remaining at around 20% throughout the whole 10-year period. These papers were fully reviewed and the number of authors, paper type, names of authors and originating department recorded. Eleven departments were responsible for 50.2% of the total number of publications with the most prolific author being responsible for 2.5% (n = 60) of the total number of UK papers. Over the 10-year period, there has been a significant change towards the publication of more clinical research at the expense of pure laboratory research in these 10 journals (chi 2 P < 0.001). There has also been a move towards multiple authorship (three or more co-authors) over the same period with fewer single-author papers (P < 0.001).

Authorship↗
PubMed1998

An unusual complication of Cloward's procedure presenting to the otolaryngologist.

We present the case of a 51-year-old lady who developed a CSF leak following a Cloward's procedure (anterior cervical surgery with fusion), which settled with conservative management. Two months following the surgery she was assessed by an otolaryngologist for persistent dysphagia and a swelling in the anterior triangle of her neck. A computed tomography (CT) scan identified a fluid-filled mass displacing the trachea and communicating with the anterior cervical vertebrae, thus confirming the persistence of a CSF leak.

Cerebrospinal Fluid↗