Accuracy of Kvaal’s radiographic and translucent dentinal root techniques of extracted teeth in Malay adults for dental age estimation

The use of teeth to estimate the age of unknown bodies provides much help especially in skeletal remains with no soft tissues left for identification. However, dental age estimation utilizing degenerative changes in teeth like dentinal translucency is often hampered with large margin of error. This study aims to compare the accuracy of Kvaal’s radiographic method (intraoral periapical radiograph) with modified Bang-Ramm dentinal root translucency method in estimating dental age in Malay adults. One-hundred teeth of maxillary and mandibular incisors and canine were collected following dental extraction. Date of birth, date of extraction, gender and ethnicity were documented prior to extraction. All teeth were assessed using two methods of dental age estimation: 1) The equation from Kvaal’s radiographic method and 2) Formula from modified Bang-Ramm dentinal root translucency method. The results from the age estimation were compared to the chronological age of the persons from whom the teeth were extracted. The average dental age estimated using both methods significantly correlated with the chronological age for both men and women. Overestimation and underestimation with mean absolute error up to 13 years and 15 years was observed in modified Bang-Ramm and Kvaal, respectively. The estimated age calculated from both methods also showed increasing standard deviation as the patient gets older. From the obtained results it is reasonable to conclude that modified Bang-Ramm method gives better accuracy for dental age estimation in Malay adults.     

Developmental competence of transported in-vitro matured macaque oocytes

This study examines in-vitro maturation (IVM) in a non-human primate model, Macaca fascicularis. The animals had hormonal injections and laparoscopic oocyte retrieval (OR)) at 12- and 24- h after human chorionic gonadotrophin (HCG). The immature oocytes were placed in tightly capped tubes containing pre-equilibrated IVM medium and transported for 5 h in a dry portable 37 degrees C incubator without CO2 supplement. Meiotic spindle was observed at 36-38- h post-HCG by polarized microscopy in 72 and 84.5% of mature oocytes collected at 12- and 24- h post-HCG oocyte retrieval intervals respectively. However, abnormal spindle formations were detected in some IVM oocytes by confocal microscopy. The IVM oocytes were also randomly selected for (i) intracytoplasmic injection with frozen-thawed epididymal M. fascicularis spermatozoa and (ii) nuclear transfer (NT) with fresh M. fascicularis cumulus cells. Embryonic development of sperm-injected embryos was not affected by the 12- and 24- h post-HCG oocyte retrieval intervals (22.5 versus 27.9% respectively). However, embryonic development of NT embryos was significantly affected by the 12- h post-HCG oocyte retrieval interval (4.5 versus 31.7% respectively; P < 0.01). In conclusion, IVM of monkey oocytes in a dry portable incubator for 5 h did not affect the maturation rate. However, the ability of primate oocytes to develop after somatic cell nuclear transfer was affected by oocyte retrieval time post-HCG.     

Magnetic resonance imaging of Asians with multiple sclerosis was similar to that of the West

Magnetic resonance imaging (MRI) of the brain is the most important paraclinical diagnostic test in multiple sclerosis (MS). The appearance of MRI in Asians with MS is not well defined. We retrospectively surveyed the first brain and spinal cord MRI in patients diagnosed to have MS, according to Poser's criteria in seven regions throughout Asia to define the MRI changes among Asians with MS. There were 101 patients with first brain, and 86 with first spinal cord MRI, 66 of whom had both. The brain MRI showed a mean of 17 lesions per patient in T2 weighted images, mostly asymptomatic. Almost all the lesions were in the white matter, particularly in the juxtacortical, deep and periventricular white matter. A third of the lesions were greater than 5 mm, 14% enhanced with gadolinium. There were more supratentorial than infratentorial lesions at a ratio of 7.5: 1. Ninety five percent of the spinal cord lesions were in cervical and thoracic regions, 34% enhanced with gadolinium. The lesions extended over a mean of 3.6 +/- 3.3 vertebral bodies in length. Fifty (50%) of the brain and 54 (63%) of the spinal MRI patients had the optic-spinal form of MS. The MRI of the optic-spinal and classical groups of patients were similar in appearance and distribution, except that the optic-spinal MS patients have fewer brain but longer and more severe spinal cord lesions. In conclusion, the brain and spinal cord MRI of Asian patients with MS was similar to that of the West, although, in this study, Asian MS patients had larger spinal cord lesions.     

Levels of benzene concentrations emitted from motor vehicles in various sites in Nibong Tebal, Malaysia

Benzene is classified as carcinogenic compound which is emitted mainly from cars. In this study, benzene was measured at various sites in Nibong Tebal (urban, suburban, town, and rural) of different traffic volume, and traffic counts were performed simultaneously. Monitoring was carried out during the morning and afternoon traffic peaks. The aim of this study is to monitor benzene concentration at several development sites with different traffic flow. The monitoring was done by using indoor air quality meter. The results obtained from monitoring show that the mean concentrations of benzene ranged from 54.7 ppb in the suburban area to 115.1 ppb in the town area. Multiple linear regression analysis correlated the benzene concentrations with traffic volume, temperature, humidity, and time of monitoring as predictors. The results show that R ² of the model was 0.97 in Taman Cowin site, and it was 0.47 in Taman Nibong Tebal Jaya site. Negative correlation was found between benzene concentration and temperature while there was positive correlation with humidity being found through the study. Pearson’s correlation indicates that gasoline vehicular exhaust could be the major source of benzene. The UK Air Quality Standards stipulated that the annual mean of ambient benzene should not exceed 5 ppb or 16.25 μg/m³. The results show that the current concentrations of benzene exceeded the permissible limits set by the UK standards.     

Sex hormones in Malay and Chinese men in Malaysia: are there age and race differences?

OBJECTIVES:

Variations in the prevalence of sex-hormone-related diseases have been observed between Asian ethnic groups living in the same country; however, available data concerning their sex hormone levels are limited. The present study aimed to determine the influence of ethnicity and age on the sex hormone levels of Malay and Chinese men in Malaysia.

METHODS:

A total of 547 males of Malay and Chinese ethnicity residing in the Klang Valley Malaysia underwent a detailed screening, and their blood was collected for sex hormones analyses.

RESULTS:

Testosterone levels were normally distributed in the men (total, free and non-sex hormone-binding globulin (SHBG) bound fractions), and significant ethnic differences were observed (p<0.05); however, the effect size was small. In general, testosterone levels in males began to decline significantly after age 50. Significant ethnic differences in total, free and non-SHBG bound fraction estradiol levels were observed in the 20-29 and 50-59 age groups (p<0.05). The estradiol levels of Malay men decreased as they aged, but they increased for Chinese men starting at age 40.

CONCLUSIONS:

Small but significant differences in testosterone levels existed between Malay and Chinese males. Significant age and race differences existed in estradiol levels. These differences might contribute to the ethnic group differences in diseases related to sex hormones, which other studies have found in Malaysia.