Thamrong Chirachariyavej

Neurological manifestations of gnathostomiasis

Neurological features of 24 patients with nervous system gnathostomiasis were reviewed. The commonest presenting features were radiculomyelitis or radiculomyelitis terminating with encephalitis, and subarachnoid haemorrhage. A primary encephalitic form was noted in 2 patients. The salient feature of the disease was a sudden onset of extremely severe radicular pain and/or headache followed by paralysis of the extremities and/or the cranial nerves. Migration signs were also the hallmark of nervous system gnathostomiasis. No single area of the nervous system was inaccessible to the highly invasive gnathostome lava. Multiplicity and/or rapid progress of lesions beyond the degree of cerebral oedema could only be explained by further migration of the parasite. Death occurred in 6 patients from direct extensive involvement of vital centres in the brain stem or from complications such as pneumonia or septicaemia. Multiple cranial nerve palsies were usually bad prognostic signs.

A carbon dioxide fatality from dry ice.

Abstract:  This report documents a rare case of carbon dioxide intoxication in a young healthy male. The deceased hid in a small plastic container, size 1.5 × 1 × 1 m, and within 5 min he was located suffering convulsions and was reported as dead within minutes. Scene investigation revealed dry ice in the container. Autopsy findings were unremarkable. The probable cause of the convulsions was carbon dioxide intoxication due to both the dry ice sublimation and the small confined space in which he was hiding. This report emphasizes the significance of scene investigation in establishing the cause of the death.

Differences between brain mass and body weight scaling to height: Potential mechanism of reduced mass-specific resting energy expenditure of taller adults

Adult resting energy expenditure (REE) scales as height( approximately 1.5), whereas body weight (BW) scales as height( approximately 2). Mass-specific REE (i.e., REE/BW) is thus lower in tall subjects compared with their shorter counterparts, the mechanism of which is unknown. We evaluated the hypothesis that high-metabolic-rate brain mass scales to height with a power significantly less than that of BW, a theory that if valid would provide a potential mechanism for height-related REE effects. The hypothesis was tested by measuring brain mass on a large (n = 372) postmortem sample of Thai men. Since brain mass-body size relations may be influenced by age, the hypothesis was secondarily explored in Thai men age < or =45 yr (n = 299) and with brain magnetic resonance imaging (MRI) studies in Korean men (n = 30) age > or =20<30 yr. The scaling of large body compartments was examined in a third group of Asian men living in New York (NY, n = 28) with MRI and dual-energy X-ray absorptiometry. Brain mass scaled to height with a power (mean +/- SEE; 0.46 +/- 0.13) significantly smaller (P < 0.001) than that of BW scaled to height (2.36 +/- 0.19) in the whole group of Thai men; brain mass/BW scaled negatively to height (-1.94 +/- 0.20, P < 0.001). Similar results were observed in younger Thai men, and results for brain mass/BW vs. height were directionally the same (P = 0.09) in Korean men. Skeletal muscle and bone scaled to height with powers similar to that of BW (i.e., approximately 2-3) in the NY Asian men. Models developed using REE estimates in Thai men suggest that brain accounts for most of the REE/BW height dependency. Tall and short men thus differ in relative brain mass, but the proportions of BW as large compartments appear independent of height, observations that provide a potential mechanistic basis for related differences in REE and that have implications for the study of adult energy requirements.

DNA database of populations from different parts in the Kingdom of Thailand

The polymorphism of 15 short tandem repeat (STR) loci-D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA from AmpFlSTR Identifiler PCR amplification kit were analysed in 929 unrelated individuals living in the north, northeast, central and south of Thailand. The comparison between these four subpopulations demonstrated that subpopulations in the north and northeast were different in two loci from all paired groups while those in the north, central and south were closely related. The inter-population comparisons between combined Thai population and other ethnic groups including Eastern Chinese, Japanese, Iraq and Egyptian revealed that Eastern Chinese and Thai were closely related.

Elemental analysis of burnt human bone for classifying sex and age at death by logistic regression

This study aims to develop a protocol for classifying sex and age groups of deceased persons by using the chemical information in burnt bone fragments. Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) has been employed to assess the chemical compositions of the burnt bones from the deceased, all of Thai nationality. By performing three ICP-OES measurements on burnt bone samples from 75 individuals, 43 males and 32 females, with an accurate record of their age at death, only six elements i.e. Al, Ca, K, Mg, P, S, were observed in the fragments above the instrumental detection limit of ICP-OES. Fifteen concentration ratios of these particular elements were examined for their significant difference with respect to sex and age group by Mann–Whitney U and Kruskal–Wallis tests, respectively. Subsequently, the significantly different ratios were employed to assess the relationship between bone chemical compositions and sex/age groups of the deceased using logistic regression analysis. Binary and multinomial logistic regressions were required to classify sex and age group at death, respectively. Regression analyses indicated that the input variables representing sex should be included for classifying the age group of the deceased. The chemical information in burnt bone fragments could be employed to assess the sex and age groups of the deceased with 79.60% and 75.10% accuracy, respectively. Chemical measurements were performed on burnt bone samples from two additional individuals to verify the developed logistic equations and classification protocol. More fractions of bones from an individual give a higher percentage of correction for classifying sex and age at death of the deceased.