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K K Bhatia

Publications and source records attributed to K K Bhatia.

At least 19 recordsLinked to original sources
PubMed2000

Seroprevalence of human T-lymphotropic virus type 1 in Papua New Guinea and Irian Jaya measured using different western blot criteria.

BACKGROUND: Endemic foci of HTLV-1 carriers have been found in the world, however, the origin of HTLV-1 in humans is still unclear. Since a distinct type of virus strain was isolated from the Solomon Islands, detailed surveys on HTLV-1 prevalence in New Guinea are important to shed light on its history of dissemination. OBJECTIVE: To clarify the seroprevalence of HTLV-1 in different regions of New Guinea Island. STUDY DESIGN: Sera from 1221 individuals (649 males, 454 females and 118 unknown) in New Guinea Island were studied for the presence of antibodies to HTLV-1 by a particle agglutination and the Western blot (WB) tests. Two different sets of criteria, proposed by WHO and Kiyokawa et al., were employed to interpret the WB test. Since the latter seemed to lack adequate specificity, the WHO criteria was used for the evaluation of the seroprevalence throughout the study. RESULTS: Seroprevalence of HTLV-1 differed by the WB criteria. By the more stringent criteria, HTLV-1 carriers were found in Madang, Chimbu and one hinterland province, Enga, in Papua New Guinea. An overall seroprevalence rate in different regions ranged from 0 to 14.6%. No seropositive individuals were found in Irian Jaya. CONCLUSIONS: To avoid overestimating the seropositivity rates, the WHO criteria would be more appropriate to employ for WB test by using the samples obtained from tropical and/or malaria endemic areas. This study is the first to show HTLV-1 infected individuals in the hinterland of New Guinea Island.

Adolescent↗
PubMed1995

Class I HLA antigens in two long-separated populations: Melanesians and South Amerinds.

Class I HLA antigens have been compared in 5,835 Melanesians of Papua New Guinea and 2,028 Amerindians of South America. The sample includes 50 PNGMel ethnolinguistic groups and 22 SAmInd groups. Both carry 15 serologically defined antigens and an undefined C allele. Except for A2 in Papua New Guinea and Cw1 in South America, these antigens are widely distributed in their respective populations. Nine (A2 and A24, B39, B60 and B62, and Cw1, Cw3, Cw4, and Cw7) are common to both. This commonality suggests that these two populations derive from an ancestral population with less polymorphism than modern East Asians. In both populations several theoretically possible haplotypes were absent, and other haplotypes were in positive disequilibrium in both. The parallels in disequilibria suggest that haplotypes are subject to selective forces acting on the level of allelic interaction. Based on three locus haplotype frequencies, the PNGMel groups form five clusters with internally typical linguistic and geographic characteristics and miscellaneous category, but SAmInd groups show no cluster.

Humans↗
PubMed1994

Assessment of the humoral and cell-mediated immunity against the Plasmodium falciparum vaccine candidates circumsporozoite protein and SPf66 in adults living in highly endemic malarious areas of Papua New Guinea.

To assess natural immunity against the circumsporozoite (CS) protein and the synthetic vaccine SPf66, immunologic studies were carried out in a highly endemic malarious area of Papua New Guinea. Antibody prevalence, antibody titers, and T cell proliferation against both antigens were measured in 214 adults. Immunologic data were analyzed with respect to longitudinal malariologic and morbidity data. Evidence of genetic traits such as glucose-6-phosphate dehydrogenase deficiency and ovalocytosis was analyzed. Antibody prevalence was high, with 79% and 84% for CS protein and SPf66, respectively, while T cell proliferation was infrequent and low, with 14% and 12% responders, respectively. Anti-CS protein antibodies increased with age but showed no association to malaria indices or morbidity. No protective value was observed with T cell responses or with humoral response to SPf66. These results provide a first description of naturally developed immunity against SPf66 and suggest further studies in to fully understand the mechanism of immunity against this antigen.

Adolescent↗
PubMed1992

The Malaria Vaccine Epidemiology and Evaluation Project of Papua New Guinea: rationale and baseline studies.

The range of possible malaria vaccines, against different species of Plasmodium and various stages in the life cycle of the parasite in both human host and mosquito vector, is reviewed. The importance, in a malaria-endemic area, of protection by a malaria vaccine against disease rather than infection is emphasized, and the ways by which disease prevention may be achieved are discussed. Mechanisms of production and presentation of vaccines are considered, including the importance of appropriate and more effective adjuvants. The variety of immune responses to malaria is set out and linked to both human and plasmodial genetic factors. Host genetics may also modify susceptibility to malaria through mechanisms which are not immunological. There is a need for entomological studies of the Anopheles vectors, especially but not only in preparation for transmission-blocking vaccines. This overall complexity justifies a multidimensional approach to epidemiology and field-site preparation. An iterative procedure is proposed for initial field evaluation, through adult male volunteers to community studies in immune adults and then to semi-immune school children, before evaluation in the principal target population of nonimmune young children. The outcome variables for epidemiological evaluation are specified. After this brief review of malaria vaccines, the baseline studies being undertaken by the Malaria Vaccine Epidemiology and Evaluation Project of the Papua New Guinea Institute of Medical Research in the Wosera area of East Sepik Province are discussed in some detail, and their rationale linked to the range and complexity of the malaria vaccines that have been reviewed. These studies are described under the headings of their principal components of epidemiology, parasitology, immunology, genetics and entomology.

Animals↗
PubMed1991

Multiple glomangiomas of lower limb.

A young man with multiple painful nodules on the left lower limb is presented. Histology of one of the nodules proved the diagnosis of glomangioma.

Adult↗
PubMed1990

Albumin--vitamin D-binding protein haplotypes in Asian-Pacific populations.

We have determined the various haplotypic combinations between alleles as well as restriction fragment length polymorphisms of two linked genetic markers, albumin and vitamin D-binding protein or group-specific component, in a number of Asian-Pacific populations. Using the partial maximum likelihood method, we constructed a phylogenetic network from the haplotype frequencies to assess relationships among the populations sampled. No systematic linkage disequilibrium was detected between most of the combinations, suggesting a lack of operation of any selection pressure at the two loci. The phylogenetic analysis confirmed the known interrelationships among various populations in the Asian-Pacific region. The Australian aborigines clustered closely with the non-Austronesian-speaking highlanders from Papua New Guinea, as expected. Similarly, the Austronesian-speaking Polynesians, Micronesians, and the Southeast Asians branched off together as a separate group. The position of the Austronesian-speaking Tolais from New Britain with respect to other populations from the Southwest Pacific was anomalous. The Tolais revealed a strong affinity with the Australian aborigines, which is inexplicable. The populations from China formed a tight cluster with other populations from the Asian-Pacific region. Genetic interrelationships of these populations with the white Australians were remote, which is in accordance with the known affinities of various human racial groups.

Alleles↗
PubMed1990

Radio-active iodine uptake in vitiligo.

Vitiligo and thyroid disease are commonly associated disorders. Twenty-two clinically euthyroid vitiligo patients were studied for functional assessment of thyroid by radioactive iodine uptake assay. Half of them showed abnormal uptake values at 24 hours. Of these patients, 90% had lower values indicating a tendency towards developing hypothyroid state. Subclinical thyroid dysfunction in vitiligo appears to be an adaptive change.

Adult↗
PubMed1989

Keratoma hereditaria mutilans (Vohwinkel's disease) with congenital alopecia universalis (atrichia congenita).

A family is described in which a boy and two girls had features of keratoma hereditaria mutilans (Vohwinkel's disease) and congenital absence of hair. None of them had any hair at birth or developed any subsequently. They had congenital, nonscarring alopecia universalis. The skin over the palms and soles showed progressive thickening, which led to mutilating deformities of the hands and fingers. Histopathological examination of the scalp skin revealed no changes in the epidermis or dermis with normal sebaceous glands and identify hair structures; the skin on the palms showed a tremendously thickened horny layer. Both conditions remained unresponsive to various topical and systemic remedies used in the past. One of the girls had a meningocoele of the dorsolumbar region and died postoperatively. The simultaneous appearance of two rare hereditary diseases in siblings of one family is being reported for the first time.

Adolescent↗
PubMed1989

HLA heterozygosity and hyperreactive malarious splenomegaly in the Upper Watut Valley of Papua New Guinea.

Hyperreactive malarious splenomegaly (HMS) represents an abnormal immune response to recurrent malarial infection. In the Upper Watut Valley of Papua New Guinea, where over 80% of adult inhabitants are known to develop the disease, human leucocyte antigen (HLA) studies have demonstrated an association between the antigen DR2 and gross splenomegaly. To test the hypothesis that the magnitude of the individual immune response to malaria is also influenced by the number of different HLA antigens present, we have studied the correlation of the level of observed heterozygosity at HLA-A, -B, -C and -DR loci with the degree of splenomegaly in adult Watut subjects. Heterozygosity per se provides additional antigens for the formation of complexes between HLA and foreign antigenic epitopes, considered crucial to mounting an immune response. Multiply heterozygous individuals were found to exhibit more intense immune responses to recurrent malarial infections than did individuals with low multiple-locus heterozygosity. On the basis of the analysis presented here, we suggest that the degree of immune response to malaria is also influenced by the level of HLA heterozygosity, although the exact mechanisms remain unclear.

Biomarkers↗
PubMed1989

Glucose-6-phosphate dehydrogenase deficiency and hereditary ovalocytosis in the Ok Tedi impact region of Papua New Guinea.

We report the distribution of two genetic traits, glucose-6-phosphate dehydrogenase (G-6-PD) deficiency and hereditary ovalocytosis (HO) in a number of populations living in the Ok Tedi impact region of Papua New Guinea. Significant interpopulation heterogeneity in the distributions of G-6-PD deficiency and HO was observed. The highlands populations of the region did not show any G-6-PD deficiency, but in the highlands fringe and lowland populations the trait has achieved polymorphic frequencies. Hereditary ovalocytosis is significantly more common in the region and is present in all the populations studied, including those in the highland valleys. Distribution patterns of the two genetic markers correspond well with the pattern of malaria endemicity in the region, providing support for the hypothesis that relates the distribution of these polymorphisms to that of malaria.

Elliptocytosis, Hereditary↗
PubMed1986

Alpha-thalassemia in Papua New Guinea.

A study of the distribution of alpha-thalassemia in Papua New Guinea (PNG) was carried out by DNA analysis. A total of 664 DNA samples were screened for alpha-thalassemia 2 and alpha-thalassemia 1 caused respectively by either deletion of one or both of the duplicated alpha-globin genes. alpha-Thalassemia 2 was detected in high frequencies in coastal and lowland regions where malaria has been holo- to hyperendemic but in low frequencies in non-malarious highland regions. The highest frequency was observed in the north coast of PNG. The distribution of alpha-thalassemia 2 seems to be in accordance with other conditions such as ovalocytosis and G6PD deficiency which are also prevalent in this population, suggesting that they may interact in protection against malaria. However, it appears to be negatively correlated with beta-thalassemia and alpha-thalassemia 1, the latter being extremely rare in this population. Analysis of the types and subtypes of the single alpha-globin gene deletion revealed a predominance of the -alpha 4.2 type in general, except in some regions in the south where the -alpha 3.7 type is prevalent. The -alpha 3.7 I subtype is the common form of the -alpha 3.7 deletion in the PNG mainland. The -alpha 3.7 III subtype, previously reported to be unique in Melanesians and Polynesians, was detected in an offshore island of PNG. However, this subtype is very rare in Melanesians from the PNG mainland.

Chromosome Deletion↗
PubMed1986

A single alpha-globin gene deletion in Australian aborigines.

alpha- and beta-thalassaemias and other haemoglobinopathies have not so far been reported in Australian Aborigines. Using a DNA mapping technique, we tested groups of Aborigines for a deletion form of alpha-thalassaemia and found that there was a single alpha-globin gene deletion (-alpha/alpha alpha) in some populations. The alpha-globin gene deletion was detected in Aboriginal DNA samples collected from Kalumburu in the Kimberley region of Western Australia. It was found also in one sample from Mowanjum, near Derby in Western Australia, and in one from Mornington Island in the Gulf of Carpentaria. It was not observed in Aboriginal DNA samples from the central desert. Further analysis of the alpha-globin gene deletion revealed that it was of the 3.7 kilobase (Kb) (-alpha 3.7) type. However, the -alpha 3.7 deletion in the Aborigines is apparently different from that found in southern Papua New Guinea as it is linked to a different zeta-globin gene polymorphism. The presence of this silent alpha-thalassaemia in several populations of Aborigines may be explained in several ways. The most likely is through contact with Macassans or other voyagers from the Indonesian and Southeast Asian areas.

Australia↗