AIM: To investigate the correlation of HOXA4 and HOXA5 promoter DNA hypermethylation with imatinib resistance among CML patients.
METHODS AND RESULTS: Samples from 175 Philadelphia positive CML patients (83 good response and 92 BCR-ABL non-mutated imatinib resistant patients) were subjected to Methylation Specific High Resolution Melt Analysis for methylation levels quantification of the HOXA4 and HOXA5 promoter regions. Receiver operating characteristic curve analysis was done to elucidate the optimal methylation cut-off point followed by multiple logistic regression analysis. Log-Rank analysis was done to measure the overall survival difference between CML groups. The optimal methylation cut-off point was found to be at 62.5% for both HOXA4 and HOXA5. Chronic myeloid leukemia patients with ≥63% HOXA4 and HOXA5 methylation level were shown to have 3.78 and 3.95 times the odds, respectively, to acquire resistance to imatinib. However, overall survival of CML patients that have ≤62% and ≥ 63% methylation levels of HOXA4 and HOXA5 genes were found to be not significant (P-value = 0.126 for HOXA4; P-value = 0.217 for HOXA5).
CONCLUSION: Hypermethylation of the HOXA4 and HOXA5 promoter is correlated with imatinib resistance and with further investigation, it could be a potential epigenetic biomarker in supplement to the BCR-ABL gene mutation in predicting imatinib treatment response among CML patients but could not be considered as a prognostic marker.
METHODS: Two pneumococcal Brunei clinical strains were serotyped by multiplex PCR method using oligonucleotide sequences derived from Centers for Disease Control and Prevention. A validated immortalised mouse brain endothelial cell line (bEnd.3) was used as a brain endothelium model for the study of the pneumococcal breach of the blood-brain barrier using an adherence and invasion assay.
RESULTS: Both of the pneumococcal clinical strains were found to be serotype 19F, a common circulating serotype in Southeast Asia and globally and possess the ability to adhere and invade the brain endothelial cells.
CONCLUSION: In addition, this is the first report on the serotype identification of pneumococci in Brunei Darussalam and their application on a brain endothelium model. Further studies are required to understand the virulence capabilities of the clinical strains.
OBJECTIVES: To investigate the effect of metformin on the expression of testicular steroidogenesis-related genes, spermatogenesis, and fertility of male diabetic rats.
MATERIALS AND METHODS: Eighteen adult male Sprague Dawley rats were divided into three groups, namely normal control (NC), diabetic control (DC), and metformin-treated (300 mg/kg body weight/day) diabetic rats (D+Met). Diabetes was induced using a single intraperitoneal injection of streptozotocin (60 mg/kg b.w.), followed by oral treatment with metformin for four weeks.
RESULTS: Diabetes decreased serum and intratesticular testosterone levels and increased serum but not intratesticular levels of luteinizing hormone. Sperm count, motility, viability, and normal morphology were decreased, while sperm nuclear DNA fragmentation was increased in DC group, relative to NC group. Testicular mRNA levels of androgen receptor, luteinizing hormone receptor, cytochrome P450 enzyme (CYP11A1), steroidogenic acute regulatory (StAR) protein, 3β-hydroxysteroid dehydrogenase (HSD), and 17β-HSD, as well as the level of StAR protein and activities of CYP11A1, 3β-HSD, and 17β-HSD, were decreased in DC group. Similarly, decreased activities of epididymal antioxidant enzymes and increased lipid peroxidation were observed in DC group. Consequently, decreased litter size, fetal weight, mating and fertility indices, and increased pre- and post-implantation losses were recorded in DC group. Following intervention with metformin, we observed increases in serum and intratesticular testosterone levels, Leydig cell count, improved sperm parameters, and decreased sperm nuclear DNA fragmentation. Furthermore, mRNA levels and activities of steroidogenesis-related enzymes were increased, with improved fertility outcome.
DISCUSSION AND CONCLUSION: Diabetes mellitus is associated with dysregulation of steroidogenesis, abnormal spermatogenesis, and fertility decline. Controlling hyperglycemia is therefore crucial in preserving male reproductive function. Metformin not only regulates blood glucose level, but also preserves male fertility in diabetic state.
OBJECTIVE: This study aimed to investigate the effectiveness and safety of sulfonylurea therapy in Chinese NDM patients during infancy before genetic testing results were available.
METHODS: The medical records of NDM patients with their follow-up details were reviewed and molecular genetic analysis was performed. Sulfonylurea transfer regimens were applied in patients diagnosed after May 2010, and glycemic status and side effects were evaluated in each patient.
RESULTS: There were 23 NDM patients from 22 unrelated families, 10 had KCNJ11 mutations, 3 harbored ABCC8 mutations, 1 had INS mutations, 4 had chromosome 6q24 abnormalities, 1 had a deletion at chromosome 1p36.23p36.12, and 4 had no genetic abnormality identified. Sixteen NDM infants were treated with glyburide at an average age of 49 days (range 14-120 days) before genetic confirmation. A total of 11 of 16 (69%) were able to successfully switch to glyburide with a more stable glucose profile. The responsive glyburide dose was 0.51 ± 0.16 mg/kg/d (0.3-0.8 mg/kg/d), while the maintenance dose was 0.30 ± 0.07 mg/kg/d (0.2-0.4 mg/kg/d). No serious adverse events were reported.
CONCLUSIONS: Molecular genetic diagnosis is recommended in all patients with NDM. However, if genetic testing results are delayed, sulfonylurea therapy should be considered before such results are received, even in infants with newly diagnosed NDM.
METHODOLOGY/PRINCIPLE FINDINGS: We investigated the human-infecting Leptospira species in blood and serum samples collected from clinically suspected leptospirosis patients admitted to three tertiary care hospitals in Malaysia. From a total of 165 patients, 92 (56%) were confirmed cases of leptospirosis through Microscopic Agglutination Test (MAT) (n = 43; 47%), Polymerase Chain Reaction (PCR) (n = 63; 68%) or both MAT and PCR (n = 14; 15%). The infecting Leptospira spp., determined by partial 16S rDNA (rrs) gene sequencing revealed two pathogenic species namely Leptospira interrogans (n = 44, 70%) and Leptospira kirschneri (n = 17, 27%) and one intermediate species Leptospira wolffii (n = 2, 3%). Multilocus sequence typing (MLST) identified an isolate of L. interrogans as a novel sequence type (ST 265), suggesting that this human-infecting strain has a unique genetic profile different from similar species isolated from rodents so far.
CONCLUSIONS/SIGNIFICANCE: Leptospira interrogans and Leptospira kirschneri were identified as the dominant Leptospira species causing human leptospirosis in Central Malaysia. The existence of novel clinically important ST 265 (infecting human), that is different from rodent L. interrogans strains cautions reservoir(s) of these Leptospira lineages are yet to be identified.