A morphometric analysis of the Late Pleistocene Human Skeleton from the Moh Khiew Cave in Thailand.

Few Late Pleistocene human remains have been found in Southeast Asia and the morphological features of the people of that age are still largely unknown due to the virtual lack of human remains in the area. Recent excavations at the Moh Khiew Cave in Thailand resulted in the discovery of a Late Pleistocene human skeleton in a relatively good state of preservation. An AMS radiocarbon date on the charcoal sample gathered from the burial gave a result of 25,800 +/- 600 BP, implying that the inhabitants of Moh Khiew Cave resided in a part of Sundaland during the last glacial age. In debates on the population history of Southeast Asia, it has been repeatedly advocated that Southeast Asia was occupied by indigenous people akin to present-day Australo-Melanesians prior to an expansion of migrants from Northeast Asia into this area. Morphometric analyses were undertaken to test the validity of this hypothesis. In the present study, cranial and dental measurements recorded from the Moh Khiew remains are compared with those of early and modern samples from Southeast Asia and Australia. These comparisons demonstrate that the Moh Khiew specimen resembles the Late Pleistocene series from Coobool Creek, Australia in both cranial and dental measurements. These results suggest that the Moh Khiew skeleton, as well as other fossil remains from the Tabon, Niah and Gua Gunung sites, represents a member of the Sundaland population during the Late Pleistocene, who may share common ancestry with the present-day Australian Aborigines and Melanesians.     

Structural gene for the phosphate-repressible phosphate-binding protein of Escherichia coli has its own promoter: complete nucleotide sequence of the phoS gene

The complete nucleotide sequence of the phoS gene, the structural gene for the phosphate-repressible, periplasmic phosphate-binding protein Escherichia coli K-12, was determined. The phosphate-binding protein is synthesized in a precursor form which includes an additional N-terminal segment containing 25 amino acid residues, with the general characteristics of a signal sequence. The amino acid sequence derived from the nucleotide sequence shows the mature protein to be composed of 321 amino acids with a calculated molecular weight of 34,427. The phoS gene is not part of an operon and is transcribed counterclockwise with respect to the E. coli genetic map. A promoter region has been identified on the basis of homology with the consensus sequence of other E. coli promoter regions. However, an alternative promoter region has been identified on the basis of homology with the promoter regions of the phoA and phoE genes, the structural genes for alkaline phosphatase and outer-membrane pore protein e, respectively.     

Character of two mutations of the beta-globin gene in beta 0-thalassemia in Azerbaijan

Molecular nature of two beta 0-thalassaemia-causing mutations in beta-globin gene in Azerbaijanian population has been elucidated, viz., C-T transition in 39 codon (nonsense mutation) and previously unknown G deletion in 82/83 codons.     

Prevalence and Associated Factors of Schistosomiasis among Children in Yemen: Implications for an Effective Control Programme

Background

Schistosomiasis, one of the most prevalent neglected tropical diseases, is a life-threatening public health problem in Yemen especially in rural communities. This cross-sectional study aims to determine the prevalence and associated risk factors of schistosomiasis among children in rural Yemen.

Methods/Findings

Urine and faecal samples were collected from 400 children. Urine samples were examined using filtration technique for the presence of Schistosoma haematobium eggs while faecal samples were examined using formalin-ether concentration and Kato Katz techniques for the presence of S. mansoni. Demographic, socioeconomic and environmental information were collected via a validated questionnaire. Overall, 31.8% of the participants were found to be positive for schistosomiasis; 23.8% were infected with S. haematobium and 9.3% were infected with S. mansoni. Moreover, 39.5% of the participants were anaemic whereas 9.5% had hepatosplenomegaly. The prevalence of schistosomiasis was significantly higher among children aged >10 years compared to those aged ≤10 years (P<0.05). Multivariate analysis confirmed that presence of other infected family member (P<0.001), low household monthly income (P = 0.003), using unsafe sources for drinking water (P = 0.003), living nearby stream/spring (P = 0.006) and living nearby pool/pond (P = 0.002) were the key factors significantly associated with schistosomiasis among these children.

Conclusions/Significance

This study reveals that schistosomiasis is still highly prevalent in Yemen. These findings support an urgent need to start an integrated, targeted and effective schistosomiasis control programme with a mission to move towards the elimination phase. Besides periodic drug distribution, health education and community mobilisation, provision of clean and safe drinking water, introduction of proper sanitation are imperative among these communities in order to curtail the transmission and morbidity caused by schistosomiasis. Screening and treating other infected family members should also be adopted by the public health authorities in combating this infection in these communities.     

High diversity of Cryptosporidium subgenotypes identified in Malaysian HIV/AIDS individuals targeting gp60 gene

Background

Currently, there is a lack of vital information in the genetic makeup of Cryptosporidium especially in developing countries. The present study aimed at determining the genotypes and subgenotypes of Cryptosporidium in hospitalized Malaysian human immunodeficiency virus (HIV) positive patients.

Methodology/Principal Findings

In this study, 346 faecal samples collected from Malaysian HIV positive patients were genetically analysed via PCR targeting the 60 kDa glycoprotein (gp60) gene. Eighteen (5.2% of 346) isolates were determined as Cryptosporidium positive with 72.2% (of 18) identified as Cryptosporidium parvum whilst 27.7% as Cryptosporidium hominis. Further gp60 analysis revealed C. parvum belonging to subgenotypes IIaA13G1R1 (2 isolates), IIaA13G2R1 (2 isolates), IIaA14G2R1 (3 isolates), IIaA15G2R1 (5 isolates) and IIdA15G1R1 (1 isolate). C. hominis was represented by subgenotypes IaA14R1 (2 isolates), IaA18R1 (1 isolate) and IbA10G2R2 (2 isolates).

Conclusions/Significance

These findings highlighted the presence of high diversity of Cryptosporidium subgenotypes among Malaysian HIV infected individuals. The predominance of the C. parvum subgenotypes signified the possibility of zoonotic as well as anthroponotic transmissions of cryptosporidiosis in HIV infected individuals.     

Soil-transmitted helminthiasis: a critical but neglected factor influencing school participation of Aboriginal children in rural Malaysia

Soil-transmitted helminthiasis (STH), among the most common neglected tropical diseases, is a major public health problem in Malaysia with a possible impact on the nutritional status and school participation of rural children. This study was carried out among Aboriginal schoolchildren, living in an endemic area for STH in Malaysia, to determine the possible relationship between intestinal helminthiasis and school absenteeism. We also evaluated whether successful treatment of the infection will affect school attendance among the subjects. Stool analysis revealed that more than 90% of the subjects were infected with at least 1 helminth species, with Ascaris lumbricoides and Trichuris trichiura infections being most prevalent. Infection of moderate-to-heavy worm burdens, low level of fathers' education and anaemia were identified as the significant predictors of high absenteeism among the subjects (P<0·05). Following treatment of the infected children, it was found that school absenteeism was reduced significantly (P<0·01). In conclusion, STH continues to have significant impacts on public health, particularly in rural communities with a negatively significant effect on the school participation of Aboriginal children. A school-based de-worming programme should be introduced and incorporated in the current educational assistance targeted towards the Aboriginal communities, under the auspices of the government.     

The effect of MII α-conotoxin and its N-terminal derivatives on Ca<Superscript>2+</Superscript>- and Na<Superscript>+</Superscript>-signals induced by nicotine in SH-SY5Y neuroblastoma cells

Nicotinic acetylcholine receptors (nAChRs) are involved in the regulation of intracellular Ca²⁺-dependent processes both in normal and pathological states. α-Conotoxins from the venom of Conus marine mollusks are a valuable tool for the investigation of the pharmacological action and functional role of nAChRs. Analogues of α-conotoxin MII labeled by Bolton-Hunter reagent (BH-MII) or fluorescein isothiocyanate (FITC-MII) on the N-terminal glycine residue have been synthesized in the present work. Fluorescence microscopy studies of SH-SY5Y neuroblastoma cells loaded with Ca²⁺ indicator Fura-2, or by both Ca²⁺ indicator Fluo-4 and Na⁺ indicator SBFI, were used to test the effect of MII modification on its ability to block Ca²⁺ and Na⁺ signals induced by nicotine. Measurements in SH-SY5Y cells showed that kinetics of the increase and recovery of the concentration of free Ca²⁺ ([Ca²⁺] _i ) upon nicotine application and washout was different from that for free Na⁺ ([Na⁺] _i ), this being evidence of differences in the mechanism of Ca²⁺ and Na⁺ homeostasis regulation. MII suppressed the nicotine-induced increase of [Ca²⁺] _i and [Na⁺] _i in a concentration-dependent manner. An additional tyrosine residue added to the N-terminus of one of the MII derivatives caused a significant decrease in the inhibitory action of MII; this decrease was even more pronounced when a large FITC label was introduced into MII. The BH-MII derivative had an inhibitory effect similar to that of unmodified α-conotoxin. MII and its iodinated derivatives are promising tools for radioligand assays.     

New Missense Mutation His2026Arg in the Factor VIII Gene Was Revealed in Two Female Patients with Clinical Manifestation of Hemophilia A

Hemophilia A is a recessive X-linked hereditary disease, so its manifestation in women is extremely rare and can be a result of an asymmetric X-chromosome inactivation or, even more rarely, of a presence of mutations in both FVIII gene alleles. We conducted a mutation screening of the FVIII gene in two female patients with clinical hemophilia A manifestation in this study. One patient had a hereditary disease; the second one was diagnosed with acquired hemophilia A as an adult. Both patients carried the same missense mutation His2026Arg. The patient with the hereditary form of the disease also had previously known microinsertion c.4379_4380 insA (p.Asn1460Lys-fs*1). We found no additional aberrations by sequencing of all functionally significant parts of the factor VIII gene of the patient with acquired hemophilia but showed clear asymmetric inactivation of X-chromosomes. Therefore, one of the possible explanations for the emergence of the hemophilic syndrome in this case can be the delayed manifestation of the FVIII gene germline mutation owing to the enhancement of hematopoiesis clonality with age.     

Recent Origin and Cultural Reversion of a Hunter–Gatherer Group

Contemporary hunter–gatherer groups are often thought to serve as models of an ancient lifestyle that was typical of human populations prior to the development of agriculture. Patterns of genetic variation in hunter–gatherer groups such as the !Kung and African Pygmies are consistent with this view, as they exhibit low genetic diversity coupled with high frequencies of divergent mtDNA types not found in surrounding agricultural groups, suggesting long-term isolation and small population sizes. We report here genetic evidence concerning the origins of the Mlabri, an enigmatic hunter–gatherer group from northern Thailand. The Mlabri have no mtDNA diversity, and the genetic diversity at Y-chromosome and autosomal loci are also extraordinarily reduced in the Mlabri. Genetic, linguistic, and cultural data all suggest that the Mlabri were recently founded, 500–800 y ago, from a very small number of individuals. Moreover, the Mlabri appear to have originated from an agricultural group and then adopted a hunting–gathering subsistence mode. This example of cultural reversion from agriculture to a hunting–gathering lifestyle indicates that contemporary hunter–gatherer groups do not necessarily reflect a pre-agricultural lifestyle.