North American Journal of Medicine and Science
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Interstitial Duplication and Distal Deletion in a Ring Chromosome 13 with Pulmonary Atresia and Ventricular Septal Defect: A Case Report and Review of Literature
Get PDFWe report on a newborn female infant with a unique ring chromosome 13. Prenatal findings include intrauterine growth restriction (IUGR); ventricular septal defect (VSD), overriding aorta, and pulmonary stenosis. Postnatal examination found mild dysmorphic features of flat fontanels and hypertelorism. Echocardiogram confirmed the diagnosis of Tetralogy of Fallot (TOF), pulmonary atresia (PA) and VSD. Cytogenetic analysis detected a mosaic pattern of a ring chromosome 13, monosomy 13 and dicentric ring chromosome in about 90%, 9% and 1% of blood lymphocytes, respectively. Oligonucleotide array comparative genomic hybridization (aCGH) analysis revealed a 28.476 Mb interstitial duplication of 13q14.11-q21.33 and a 10.217 Mb distal deletion of 13q33.2-q34. Review of the literature suggested three groups of ring chromosome 13 with variable phenotypes based on the size of 13q deletions and noted two cases of ring chromosome 13 with a distal deletion defined by genomic analysis. A heat map of ring chromosome 13 phenotypes was constructed. The present case represents a new group of ring chromosome 13 with compound segmental duplication and deletion. This study demonstrates the importance of genomic characterization of constitutional ring chromosome for better disease classification and phenotype correlation.[N A J Med Sci. 2013;6(4):208-212. DOI: 10.7156/najms.2013.0604208
Interstitial Duplication and Distal Deletion in a Ring Chromosome 13 with Pulmonary Atresia and Ventricular Septal Defect: A Case Report and Review of Literature
Get PDFWe report on a newborn female infant with a unique ring chromosome 13. Prenatal findings include intrauterine growth restriction (IUGR); ventricular septal defect (VSD), overriding aorta, and pulmonary stenosis. Postnatal examination found mild dysmorphic features of flat fontanels and hypertelorism. Echocardiogram confirmed the diagnosis of Tetralogy of Fallot (TOF), pulmonary atresia (PA) and VSD. Cytogenetic analysis detected a mosaic pattern of a ring chromosome 13, monosomy 13 and dicentric ring chromosome in about 90%, 9% and 1% of blood lymphocytes, respectively. Oligonucleotide array comparative genomic hybridization (aCGH) analysis revealed a 28.476 Mb interstitial duplication of 13q14.11-q21.33 and a 10.217 Mb distal deletion of 13q33.2-q34. Review of the literature suggested three groups of ring chromosome 13 with variable phenotypes based on the size of 13q deletions and noted two cases of ring chromosome 13 with a distal deletion defined by genomic analysis. A heat map of ring chromosome 13 phenotypes was constructed. The present case represents a new group of ring chromosome 13 with compound segmental duplication and deletion. This study demonstrates the importance of genomic characterization of constitutional ring chromosome for better disease classification and phenotype correlation. [N A J Med Sci. 2013;6(4):208-212. DOI: 10.7156/najms.2013.0604208
Magnesium Intake, Insulin Resistance, and Type 2 Diabetes
No full textMagnesium is one of essential minerals abundant in whole grains, green leafy vegetables, legumes, and nuts. Accumulating evidence suggests that adequate magnesium intake is important in maintaining glucose and insulin homeostasis and thereby in protecting against the development of type 2 diabetes. Observational evidence, primarily from cross-sectional studies, has shown that low dietary magnesium intake are inversely related to glucose intolerance and/or insulin resistance. Results from prospective studies of magnesium intake and risk of incident type 2 diabetes have been generally consistent; however, there are as yet no clinical trials examining the efficacy of magnesium supplementation or consumption of major magnesium-rich foods on the primary prevention of type 2 diabetes. The efficacy of oral magnesium supplementation as adjunct therapy in improving glycemic control among non-diabetic or diabetic patients has been suggested in some small randomized clinical trials. In addition, recent evidence from human population data suggested that common variants of two genes (ion channel transient receptor potential membrane melastatin 6 and 7, TRPM6 and TRPM7) critical for magnesium homeostasis may confer a susceptibility to type 2 diabetes in individuals with inadequate magnesium intake, although further replication in large-scale studies is warranted. This presentation provides an overview of the current evidence linking magnesium intake to insulin resistance and type 2 diabetes from observational studies to intervention trials.
A Review of Vulvar and Vaginal Cancers in Ibadan, Nigeria
Get PDFThe objectives of this study are to give an update on the previous studies on vulvar and vaginal cancers from the University College Hospital (UCH), Ibadan, Nigeria, to elucidate any changes in pattern, and to enumerate some of the factors affecting the management of these cancers at the UCH today. All the cases of cancer of the vulva and vagina seen at the UCH between January 1981 and December 2008 were reviewed and re-classified according to the World Health Organization (WHO) histological classification of 2004. The results are as follows: Vaginal and vulvar cancers were the 4th (1.4%) and 5th (1.2%) most common of the 5913 gynecological cancers seen. The mean age was 49.7 years. Squamous cell carcinoma (SCC) was the most common histological type. Notably, vulvar cancer is more common than vaginal cancer in the US and the UK and this opposes our findings. We studied time periods before and after the year 2000, and found vaginal cancer to be more common before and vulvar cancer after the year 2000. We suggest that this may be related to the introduction of the FIGO guidelines in 2000. We conclude that it is important to strictly adhere to the FIGO guidelines in determining the primary site of origin of these cancers in patients with advanced local disease as this distinction has implications for clinical management.[N A J Med Sci. 2013;6(2):76-81. DOI: 10.7156/najms.2013.0602076
Non-Invasive Prenatal Diagnosis: A Comparison of Cell Free Fetal DNA (cffDNA) Based Screening and Fetal Nucleated Red Blood Cell (fnRBC) Initiated Testing
Get PDFCurrent prenatal diagnosis uses non-invasive procedures of maternal serum screening and ultrasound exam to evaluate the risk of chromosomal abnormalities and invasive procedures of chorionic villus sampling and amniocentesis for the diagnosis of cytogenomic abnormalities and gene mutations. The discovery of cell free fetal DNA (cffDNA) in maternal blood prompted the application of massive parallel sequencing to screen fetal aneuploidies. The multi-center large-scale validation of cffDNA based prenatal screening has resulted in rapid integration of this close-to-diagnostic non-invasive procedure into clinical application. Further improvement of this approach could lead to the screening of pathogenic copy number variants and known disease-causing gene mutations. The success from cffDNA fuels efforts in isolating circulating fetal nucleated red blood cells (fnRBCs) for direct non-invasive prenatal testing of fetal genetic disorders. Various isolation and enrichment methods based on the physical and biologic features of the fnRBCs have been developed but the analytic and clinical validities have not yet been established. The cffDNA based prenatal screening has significantly reduced unnecessary invasive procedures. Future breakthrough on fnRBC initiated prenatal testing will further shift the paradigm toward non-invasive prenatal diagnosis.[N A J Med Sci. 2013;6(4):194-199. DOI: 10.7156/najms.2013.0604194
Building Reproductive Genetic Services from Bottom Up: Over 30-year Experience of a Major Prenatal Diagnostic Center in Guangdong Province
Get PDFPrenatal diagnosis plays an important role in preventing birth defects and improving birth quality. Through continuous efforts from the past three decades, the Guangdong Women and Children’s Hospital has transform a small department of medical genetics into a prenatal center for genetic disease diagnosis and treatment (PCGDDT). A wide spectrum of genetic tests including clinical cytogentics, biochemical screening and molecular genetics has been performed. A biobank of patient specimens for translational research has been established. PCGDDT has been one of the key disciplines of Guangdong Women and Children Hospital and master degree training hospital for Guangzhou Medical University, state-level professional training base in clinical and laboratory technology, and priority specialty of Guangdong Province. Our experience represents a bottom up approach to build sustainable hospital-based and institute-affiliated genetic services in China. [N A J Med Sci. 2013;6(4):216-218. DOI: 10.7156/najms.2013.0604216
Enzymatic Screening and Diagnosis of Lysosomal Storage Diseases
Get PDFLysosomal storage diseases (LSDs) are a group of more than 50 genetic disorders. Clinical symptoms are caused by the deficiency of specific enzyme (enzymes) function and resultant substrate accumulation in the lysosomes, which leads to impaired cellular function and progressive tissue and organ dysfunction. Measurement of lysosomal enzyme activity plays an important role in the clinical diagnosis of LSDs. The major enzymatic testing methods include fluorometric assays using artificial 4-methylumbelliferyl (4-MU) substrates, spectrophotometric assays and radioactive assays with radiolabeled natural substrates. As many effective treatment options have become available, presymptomatic diagnosis and early intervention are imperative. Many methods were developed in the past decade for newborn screening (NBS) of selective LSDs in dried blood spot (DBS) specimens. Modified fluorometric assays with 4-MU substrates, MS/MS or LC-MS/MS multiplex enzyme assays, digital microfluidic fluorometric assays, and immune-quantification assays for enzyme contents have been reported in NBS of LSDs, each with its own advantages and limitations. Active technical validation studies and pilot screening studies have been conducted or are ongoing. These studies have provided insight in the efficacy of various methodologies. In this review, technical aspects of the enzyme assays used in clinical diagnosis and NBS are summarized. The important findings from pilot NBS studies are also reviewed.[N A J Med Sci. 2013;6(4):186-193. DOI: 10.7156/najms.2013.0604186
The Clinicopathologic Pattern of Prostatic Carcinoma in Lagos, Nigeria
Get PDFThis is a review of the clinicopathological pattern of prostatic carcinoma in Lagos, Nigeria. The mean age was 68.48 years. 20% of our patients were asymptomatic at presentation, significantly higher than values from most previous Nigerian studies, likely due to an established PSA screening program. This however did not appear to translate to better disease outcomes, likely because radical prostatectomy was not offered as a treatment option for early disease. 68.6% of symptomatic patients presented with lower urinary tract symptoms, and 4.4% had a family history of prostate cancer. The median PSA value at presentation was 58.90ng/ml. Clinical stages II and III disease were most common, 42.5 and 30% respectively. Gleason scores 6 and 8 were the most common (23.3 and 20% respectively). The clinical stage and the age showed the best correlation with disease progression evidenced by increased PSA 2 months after treatment (PSA progression) and metastasis during follow up. The Gleason score also showed good correlation with these parameters while the pre-treatment PSA showed poor correlation, possibly due to the high incidence of urogenital infections and prostatitis in this environment. The incidence of PSA progression and metastasis were 0.35 and 0.54 per patient year of follow up respectively.
Rhythm Definition of Biomarkers for an Objective Measure of Autism
Get PDFA review of the literature noted 16 biomarker candidates that could be utilized to develop an objective measure of autism, and we found that 11 of them were quantifiable in saliva collected twice in the evening from 12 neurotypical adults. These biomarkers (and body systems) in which autism is manifest were: Glutamine and Glutamic acid (ubiquitous), CD26 (gastrointestinal); C4B and IFNγ (immunologic); Cortisol, Melatonin, Testosterone (neurologic); and GSH, GSSG, Metallothionein-2 (toxicologic). These 11 biomarkers also monitor the three unifying concepts of the cause of autism: oxidative stress, immune glutamatergic dysfunction, and pineal gland malfunction. Saliva was used since, of the typical body fluids, its collection is least stressful to the individual. Because the concentrations of biomarkers can vary dramatically over 24-hours, circadian studies are being planned, since defining the circadian rhythm of each biomarker will allow future testing using as few assays at appropriate times as necessary in order to obtain a valid objective measure of autism. A diagnosis based on chemical measurements can then be made, resulting in a patient-specific profile that will rank the biomarkers in the order of their difference from normal. It is hoped that this profile will provide a guide for biomarker replacement therapy to improve the symptoms of autism, as has been demonstrated for melatonin and several components of the methionine cycle (involved in detoxification).[N A J Med Sci. 2013;6(3):154-157. DOI: 10.7156/najms.2013.0603154
Autism and Diet: Is There a Connection?
Get PDFAutism spectrum disorder is a relatively common developmental brain disorder that typically presents in children under the age of two. Autism is characterized by a broad range of functional brain deficiencies centered in the area of emotional intelligence. There is little doubt that autism has been increasing in all countries, but the question arises why is this so and what can be done about it? Because little is known about the cause of autism, efforts to answer these important questions cause anguish for both medical communities and patients and their families who live with this challenging disorder every day.[N A J Med Sci. 2013;6(3):158-162. DOI: 10.7156/najms.2013.0603158