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Background: Frontoethmoidal encephalocele (FEE) is a neural tube defect (NTD) characterized by a congenital bone defect in the anterior cranium and herniation of the intracranial mass through the defect. The C677T mutation in the 5,10-methylenetetrahydrofolate reductase gene ( MTHFR) has been reported as a genetic risk factor for spina bifida. However, the role of the MTHFR in the pathogenesis of FEE remains to be clarified. Methods: A hospital-based survey of FEE patients who were referred to the Department of Neurosurgery and Plastic Surgery, Malang General Hospital, East Java, Indonesia was conducted. Genetic screening of MTHFR substitutions in 13 patients and eight mothers from 11 affected families were performed using a combination of polymerase chain reaction (PCR), denaturing high-performance liquid chromatography (DHPLC), and direct sequencing. Results: In total, 130 patients with FEE among 138 NTD patients (94.2%) were identified. The ratios of cranial encephalomeningocele to spinal meningocele (32 : 1) and of FEE to occipital encephalomeningocele (32 : 1) were higher than those in other populations. Five substitutions were detected in the MTHFR: C121T, C677T, C1060T, A1298C, and G1793A. No significant differences were found in the frequency of each nucleotide substitution between patients or mothers and controls. In addition, none of the subjects in this study were homozygous for T at nucleotide position 677. Conclusion: FEE is the most common form of NTD in East Java, Indonesia. Genetic analysis of 11 affected families suggests that the MTHFR gene is not associated with the development of FEE, although the number of FEE families analyzed in this study was very limited. [ABSTRACT FROM AUTHOR]

Southeast Asian ovalocytosis (SAO) is a red blood cell abnormality common in malaria-endemic regions and caused by a 27 nt deletion of the band 3 protein gene. Since band 3 protein, also known as anion exchanger 1, is expressed in renal distal tubules, the incidence of SAO was examined in distal renal tubular acidosis (dRTA) in Malays in Kelantan, Malaysia. Twenty-two patients with dRTA and 50 healthy volunteers were examined for complication of SAO by both morphological and genetic analyses. SAO was identified in 18 of the 22 dRTA patients (81.8%), but only two of the 50 controls (4%). The incidence of SAO was significantly high in those with dRTA (p<0.001), indicating a dysfunctional role for band 3 protein/anion exchanger 1 in the development of dRTA. [ABSTRACT FROM AUTHOR]

Abstract Background : Glucose-6-phosphate dehydrogenase (G6PD) deficiency has increased prevalence rates in tropical Africa, tropical and subtropical Asia and some parts of the Mediterranean. Earlier studies on G6PD deficiency in the Philippines have shown prevalence rates of 4.5% to 25.7%. Methods : In the present study, 3278 male newborns were screened for G6PD deficiency using the modified formazan method, a simple screening procedure affordable in the setting of a developing country. Subjects with positive screening results were recalled for confirmatory testing using a commercial assay kit for quantitative enzyme determination. Results : Of the 3278 boys studied, 186 revealed positive screening results. Of the 186, 65 boys had confirmatory testing. Of these 65 boys, 45 were confirmed to have G6PD deficiency and 20 had normal results. This study reveals an incidence of G6PD deficiency of 3.9% among male Filipinos. Conclusion : This study recommends the inclusion of G6PD deficiency in the panel of disorders for newborn screening among Filipino newborns. [ABSTRACT FROM AUTHOR]

Multiplex polymerase chain reaction (PCR) using multiple tandem forward primers and a common reverse primer (MPTP) was recently established as a comprehensive screening method for mutations in X-linked recessive diseases. In the work reported here, MPTP was used to scan for mutations of the glucose-6-phosphate dehydrogenase (G6PD) gene. Mutations in exons 3,4,5,6,7,9, 11, and 12 of the G6PD gene were screened by MPTP in 93 unrelated Malaysian patients with G6PD deficiency. Of the 93 patients, 80 (86%) had identified mutations. Although all of these were missense mutations, identified nucleotide changes were heterogeneous, with 9 mutations involving various parts of the exons. These 9 mutations were G-to-A nucleotide changes at nucleotide 871 of the G6PD gene (G871A), corresponding to G6PD Viangchan, G6PD Mediterranean (C563T), G6PD Vanua Lava (T383C), G6PD Coimbra (C592T), G6PD Kaiping (G1388A), G6PD Orissa (C131G), G6PD Mahidol (G487A), G6PD Canton (G1376T), and G6PD Chatham (G1003A). Our results document heterogeneous mutations of the G6PD gene in the Malaysian population. [ABSTRACT FROM AUTHOR]

Presents information on the testing of a common reverse primer to scan for the mutations of the glucose-6-phosphate dehydrogenase (G6PD) gene. Information on G6PD deficiency; Number of patients that were screened positive for a mutation in the gene.

The allele frequency of a L1 retroposon insertion into intron 30 of the neurofibromatosis type 1 (NF1) gene was determined by analyzing amplified fragment lengths in seven Asian or Pacific populations; namely, Japanese, Chinese, Indian, Malay, Filipino, Indonesian and New Guinean. Nearly 100 chromosomes from each group were analyzed. The presence of the L1 insertion was identified by the appearance of an abnormally large PCR-amplified product. The insertion frequency varied from 0.45 to 0.75, depending on the population group. Malay and Indonesia populations were found to have the highest insertion frequencies (0.75 and 0.72, respectively), while the wild-type genotype was more prevalent in Indians. The lowest insertion frequency (0.45), observed in Indians, was nearest to that reported in Westerners (0.35). The different L1 insertion frequencies found in Asian and Pacific groups reflect a major divergence in these human populations. Japanese and Chinese populations showed the highest heterozygosity (0.50), suggesting the usefulness of this polymorphism in linkage analysis in these populations. [ABSTRACT FROM AUTHOR]

We have developed a fast and comprehensive method to scan for point mutations in a gene on X chromosome. A target region of the gene is first amplified. Then, using the amplified product as a template, PCR is carried out with multiple short-length forward primers arrayed in tandem in the scanned region, and a common reverse primer. The absence of amplified product defines the site of a mutation within a narrow region of the primer recognition site. To evaluate our method, point mutations in exon 12 of the human glucose-6-phosphate dehydrogenase (G6PD) gene were used as a model system. Out of 12 Singaporean G6PD-deficient patients, 6 cases were shown by the method to have a nucleotide change in this exon. Sequence analysis confirmed the presence of a nucleotide change in the region identified by our scanning. Thus, our method is accurate in localizing mutations within a narrow region, and allows large numbers of samples to be handled simultaneously. [ABSTRACT FROM AUTHOR]

Background: Thymic large cell neuroendocrine carcinoma (LCNEC) is extremely rare. The detailed clinical features of thymic LNCECs remain unknown.Case presentation: A 90-year-old man with a history of diabetes mellitus, chronic renal failure, and an abdominal aortic aneurysm underwent computed tomography for follow-up, which showed an anterior mediastinal tumor, measuring 31 mm × 28 mm in diameter. Magnetic resonance imaging showed an iso-intensity mass on T1-weighted images and high intensity on T2-weighted images. 18F-Fluorodeoxyglucose-positron emission tomography showed marked uptake in the mass, which was diagnosed as invasive thymoma or thymic carcinoma. Video-assisted thoracic surgery through the left thoracic cavity was converted to median sternotomy due to severe adhesions between the left lung and the chest wall. Partial thymectomy and combined partial resection of left upper lobectomy and the first and the second costal cartilages were performed. The pathologic diagnosis was thymic LCNEC, Masaoka stage III. The patient developed pleural dissemination and left lung metastases in 5 months and died 12 months after surgery.Conclusions: Thymic LCNEC has high malignant potential. More cases need to be studied. [ABSTRACT FROM AUTHOR]