a-Thalassemia is one of the most serious genetically transmitted diseases creating health problems in many countries, with gene frequencies varying between 1% and 98% throughout the tropics and subtropics. More than 95% of recognized a-thalassemia involved deletion of 1 or both a-globin genes from chromosome 16p13.3 (1, 2). These gene deletions caused mild a-thalassemia-2 and severe thalassemia-1, respectively. The most common type of thalassemia-1 in the Asian population is the Southeast Asian type (SEA) (3). Even thought carriers of the a-thalassemia-1 with SEA type do not manifest any clinical symptoms, couples who are both carriers have a 25% chance of conceiving a homozygous fetus, which manifests as Bart's hydrops fetalis, the most severe thalassemic syndrome. All of these fetuses die either in utero or soon after birth (4-6). In addition, approximately 75% of mothers carrying fetuses with homozygous for the a-thalassemia-1 SEA type will develop toxemia of pregnancy (7). An investigation of a-thalassemia-1 SEA type is therefore essential for carrier couples and for prenatal diagnosis of fetus conceived by couples who are both carriers of this type of gene deletion.The gap-PCR analysis currently used to diagnose athalassemia-1 SEA type is based on multiplex amplification at the breakpoint area of thalassemia-1 with SEA type and the wide type a-globin gene allele. The technique requires labor intensive, time-consuming, and post-PCR processing steps (8). In an effort to develop a more straightforward diagnostic test, quantitative realtime PCR with specific probes (9, 10) has been used for detection of a-thalassemia-1 SEA type. Probe-based assays are generally used for multiplex real-time PCR analysis. However, they are relatively expensive. Realtime PCR with SYBR Green1 followed by melting curve analysis has also been use to enhance the speed Abstract a-Thalassemia-1 Southeast Asian (SEA) type is the most common genetic disorder in the Asian population. Couples who are both carriers have a 25% chance of conceiving Bart's hydrops fetalis. Therefore, results from carrier screening and prenatal diagnosis frequently need to be available rapidly. A rapid technique for diagnosis of a-thalassemia-1 SEA type was implemented. The technique used is based on real-time gap-PCR and high resolution melting (HRM) analysis of the amplified fragment using the Rotor-Gene 6000Ô. The DNA samples used for amplification were obtained from whole blood, cord blood, and chorionic villus sampling (CVS). With this method, the a-thalassemia-1 SEA allele can be easily distinguished from wild type a-globin gene allele. The real-time gap-PCR and HRM analysis offers additional benefits including minimal labor, rapid turnaround time, and a decreased risk of PCR carryover contamination. It is cost-effective and safe, does not require fluorescently labeled probe and hazardous chemicals. Moreover, it is accurate showing 100% concordance with conventional gap-PCR analysis.

SummaryCytokines are involved in regulating HIV-1 infection. They are also placental environment major components. We assessed the potential impact of HIV-1 infection and/or anti-retroviral drugs on the placental cytokine profiles that may be involved in controlling HIV-1 placental dissemination. Placental explants were obtained after elective caesarean section from anti-retroviraltreated HIV-1-infected pregnant women and from HIV-1 non-infected pregnant women. The main placental cytokines were assessed for protein secretion in the supernatants of 24-h placental culture explants and/or in uncultured placental explants for mRNA expression levels. The cytokine profiles were different between the HIV-1-infected and the non-infected groups. Higher medians of leukaemia inhibiting factor (LIF), tumour necrosis factor (TNF)-a and interleukin (IL)-8 secretion were found in the 24-h culture supernatant of term placenta from HIV-1-infected women. High median levels of IL-16 and regulated upon activation normal T cell expressed and secreted (RANTES) levels were found in both groups. The mRNA expression medians were lower for TNF-a and IL-8 and higher for stromal cell-derived factor-1 (SDF-1) in uncultured placental explants from HIV-1-infected women. In the HIV-1-infected group, but not in the non-infected group, the secretion levels of TNF-a and IL-8, as well as their mRNA expression levels, were highly positively correlated; furthermore, their secretion levels were correlated positively with LIF and IL-10 secretion levels. We found no correlation between the cytokine levels and the immunovirological status of the HIV-1-infected mothers or the type or duration of treatment. These results highlight the potential impact of HIV-1 and of the anti-retroviral treatments on the placental cytokines pattern, independently of their anti-viral activity.

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Red cell indices and formulas have been established as simple, fast, and inexpensive means for discrimination between the β-thalassemia (β-thal) trait and iron deficiency. However, there were no reports of the diagnostic reliability of different red cell indices and formulas in discrimination of β-thal trait from iron deficiency in the Thai population. The aim of this study was to examine the diagnostic accuracy of five red cell indices [red blood cell (RBC) count, mean corpuscular volume (MCV), mean corpuscular hemoglobin (Hb) (MCH), mean corpuscular Hb concentration (MCHC), and red cell distribution width (RDW)] and eight formulas (Sirdah, Green & King, RDW Index, Menzler, England & Fraser, Ehsani, Srivastava, and Shine & Lal). Their sensitivity, specificity, positive and negative prognostic value and efficiency, were analyzed in 77 Thai school children, 21 with the β-thal trait and 56 with iron deficiency. The Sirdah and Srivastava formulas proved to be the most reliable indexes as they had 100.0% sensitivity and negative predictive value, the highest efficiency (97.4%), and the highest Youden's Index value (96.4%). Therefore, these formulas could be used in initial discrimination of the β-thal trait from iron deficiency in Thai school children.