Aspartic acid racemization with correlation to age: a forensic perspective

Objective: To estimate age through aspartic acid racemization of human dentin for forensic analysis, and to calculate the margin of error between chronological age and estimated age by racemization method

Study Design: Cross-sectional comparative study

Place and Duration of Study: Dental Outpatients' Department, Ziauddin Hospital, Karachi, from 2011 to 2014

Methodology: Patients from dental orthodontics department were selected. Verbal expressed consent was taken from the participants. Preliminary data was entered in a specially designed performa having name, chronological age, gender, socio-economic status. L and D ratio of aspartic acid were quantified in dentin for each tooth by High-Pressure Liquid Chromatography technique. Results of 100 samples with known age were used during study to estimate co-efficient of racemization. Regression equation was derived by plotting 85 samples of known age and KR as independent and dependent variables and least square equation was derived - Age = -4.391 +347.396 [co-efficient of racemization]

Results: The estimated co-efficient of determination was 0.74, meaning thereby that the regression equation was 74% correct for estimating age. The calculated correlation between chronological age and co-efficient of racemization was 0.834, which is interpreted as a very strong and positive correlation. The co-efficient of racemization increased with the age. The mean chronological age [38.44 +/- 13.22] years were statistically similar to the mean calibrated age [37.52 +/- 12.36] years. The median of actual and calibrated age was found to be 3.4 with inter-quantile value of 13. No statistically significant difference was observed among gender [p=0.837], or socioeconomic status [p=0.35]

Conclusion: Racemization of human dentin could be used as one of the reliable method for estimating age. HPLC is a reliable technique to estimate the co-efficient of racemization because it is highly reproducible, cost-effective and convenient. However, the procedure should be optimized and standardized within all laboratories for quality assurance

Development of 19-plex Y STR system and polymorphism studies in Pakistani population / 药物分析学报

For the development of 19-plex Y STR system and polymorphism studies in locl ethnic populations sixteen markers of non-recombining regions (NRY) of Y chromosome, which show high power of discrimination among individuals, were selected in this study. Blood samples (600) were e.ollected from the males of three most common castes of Pakistani population (Arnin, Awan and Rajput) with different parent lineages. Three markers (DYS385a/b, DYS389Ⅰ/Ⅱ and YCAⅡa/b) among 16 Y STRs are double-targeted regions of the Y chromosome and thus provide two polymorphie peaks for each respective primer set. These 16 Y-STRs were developed into Megaplex system for simultaneous amplification of all markers within the population. The overall power of discrimination observed in focused populations was 60.5%, 66.5% and 55% in Rajput, Awan and Arain casts respectively. This discrimination power will be helpful in haman identification for forensic casework studies including sexual assaults and paternity testing.

Somatic embryogenesis in wild relatives of cotton (Gossypium Spp.) / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Wild cotton species can contribute a valuable gene pool for agronomically desirable cultivated tetraploid cultivars. In order to exploit diploid cotton a regeneration system is required to achieve transformation based goals. The present studies aimed at optimizing the conditions for regeneration of local varieties as well as wild species of cotton. Different callus induction media were tested with varying concentrations of hormones in which sucrose was used as nutritional source. Different explants (hypocotyls, cotyledon, root) were used to check the regeneration of both local cotton plants and wild relatives using T & G medium, BAP medium, CIM medium, EMMS medium, and cell suspension medium. Different stages of embryogenicity such as early torpedo stage, late torpedo stage, heart stage, globular stage and cotyledonary stage were observed in wild relatives of cotton. The results of this study pave the way for establishing future transformation methods.

Frequency and clinical Importance of Anti - TG auto antibodies [ATG]

To note the frequency of anti thyroglobulin autoantibodies [ATG] and its clinical importance in 25 follow-up cases of differentiated thyroid cancer [DTC]. Design: A case control study. Place and Duration of Study: The total duration of study was one year [September 2000 to August 2001]. Majority of the patients included were the routine follow-up cases at IRNUM, Peshawar. However, few of the cases were also included from NORI, Islamabad and AFIP, Rawalpindi. Subjects and All the patients who had undergone sub-total or total thyroidectomy followed by I-131 ablation therapy were selected for this study. Thyroglobulin [Tg] and ATG were measured using immunometric assay technique with reference range of non-detectable to 40 IU/L. Patients with serum Tg level ' 10 ng/mL were included in group-1 [n=15] and all the remaining [n=10] in group-2. Overall, 11 patients showed ATG titer above the pre-defined threshold level. In group -1 patients, 8 had positive anti-Tg antibodies in their sera while in group-2, it was positive in only 3 cases. Risk of relapsing metastatic/recurrent disease in association with ATG was calculated which showed that patients with positive ATG have almost seven - fold increased risk of having recurrent/metastatic disease than those who do not. Samples for s-Tg measurements must also be evaluated for ATG status because more than one-third of these patients have positive ATG titer in their sera. Although in the presence of positive ATG, the risk of concurrent metastatic/recurrent thyroid disease is increased but still more studies are required to support its significance