North American Journal of Medicine and Science
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The Spectrum of Cytogenomic Abnormalities in Patients with Developmental Delay and Intellectual Disabilities
Get PDFCurrent clinical cytogenomics laboratory uses array comparative genomic hybridization (aCGH) or single nucleotide polymorphism (SNP) chip as first-tier test supplemented with routine karyotyping and fluorescent in situ hybridization (FISH) for patients with developmental delay (DD), intellectual disability (ID), multiple congenital anomalies (MCA) and autistic spectrum disorders (ASD). A spectrum of cytogenomic abnormalities including numerical chromosomal abnormalities, unbalanced and balanced structural and cryptic rearrangements, and recurrent genomic disorders have been detected 10~20% of patients with DD/ID/MCA/ASD and collectively present in approximately 0.8% of a general population. The characterization of genomic coordinates and gene contents for these abnormalities has enabled accurate mapping of candidate genes and correlating genotypes with phenotypes and thus more informative genetic counseling. Future application of WGS will expand this spectrum of cytogenomic abnormalities by including complex and cryptic structural variants. Further delineation of molecular mechanisms of these cytogenomic abnormalities and development of novel therapeutic approaches will ultimately lead to disease-specific personalized management and precision treatment.
Persistent Melanoma with a Striking Well Differentiated Neural Component
Get PDFAlthough neurotropism and focal neural differentiation are fairly common in the setting of desmoplastic and spindle cell melanoma, in situ melanoma exhibiting a significant well differentiated neural component is very rare. We report the case of a 70 year old man with persistence of melanoma at the site of excision of a melanoma in situ of lentigo maligna type. The patient presented three years later noting thickening of the skin at the site of his previous surgery. Scar revision led to the unexpected identification of underlying melanoma with a marked and striking neural component. Obvious melanoma was noted in the epidermis and dermis, along with a deeper spindle cell component that exhibited routine histologic and immunopathologic features of a well differentiated neural tumor. If not for the gradual transitions and continuity of these components, a second bystander tumor would have been considered. Without the ample specimen received, misdiagnosis would have been likely. We review phenomenon of neural differentiation with our unusual illustrative case.
Factors Influencing Delay in Epilepsy Surgery: A Retrospective Data Review for a Tertiary Referral Center
Get PDFMedically intractable focal epilepsy affects a third of patients with seizures which are potentially surgically remediable. Several factors have been suggested for the reasons of the delays in epilepsy surgery. Nationally, the average time to surgery after onset of seizures is 20 years. We analyzed the characteristics of population of patients in Western New York who underwent surgery for refractory epilepsy, the time duration between onset of epilepsy and surgery, and the factors influencing the time duration, in order to determine whether there is any difference between the data from Western New York and all states in United States of America. Retrospective chart review of 51 patients was performed on the patients diagnosed with refractory epilepsy from 2003-2014 who underwent surgery at our center. Demographic Data such age, gender, ethnicity, insurance information, seizure severity, number of medications, EEG results, MRI lesions, and time to surgery were collected. Linear regression forward model was used for analysis with significance value set at 0.05. Mean waiting time to surgery at our center was shorter (13.5 versus 20 years) compared to the other centers in the United States of America. Eighty-one% (37) of the patients were diagnosed with lesions on MRI, of which 13% (6) were tumors. Mean waiting time of patients with a lesion was 13.4 years versus 15.5 years for patients without a lesion. Mean time for pediatric patients was 4.5 years and while for an adult patient was 21 years. When linear regression forward model was applied, a shorter time to surgery was associated with pediatric patients with B = 11.81 (2.42, 21.2), p-value = 0.016. Our study suggests that pediatric patients underwent surgeries earlier compared to adult population, which may be due to earlier identification by the local pediatric neurologists. Further research with bigger sample size is needed to probe the factors influencing the time duration between onset of epilepsy and candidacy of epilepsy surgery
Overview on Current Management of Hepatic Encephalopathy
Get PDFHepatic encephalopathy (HE) is one of the most serious complications of chronic or fulminant liver failure. It’s main clinical manifestations involving disturbance of consciousness, behavioral disorders and coma. According to the degree of impaired consciousness, neurological signs and EEG changes, the clinical course of HE may be divided into four phases, ranging from cognitive alteration to coma and even death, staging contribute to early diagnosis, prognosis and therapeutic evaluation. Management of HE primarily involves avoidance of precipitating factors, protect live function from further damage, treatment of ammonia poisoning and regulation of neurotransmitter. This review mainly discusses the current available options for therapy in Hepatic encephalopathy and some new studied agents.[N A J Med Sci. 2016;9(2):59-65. DOI: 10.7156/najms.2016.0902059
A Comparative Study of Social Scene Parsing Strategies between Children with and without Autism Spectrum Disorder
Get PDFAutism spectrum disorder (ASD) is a complex developmental disability characterized by deficits in social interaction. Gaze behavior is of great interest because it reveals the parsing strategy the participant uses to achieve social content. The legacy features in gaze fixation, such as time and area-of-interest, however, cannot comprehensively reveal the way the participant may cognize the social scene. In this work, we investigate the dynamic components within the gaze behavior of children with ASD upon the carefully-selected social scene. A cohort of child participants (n = 51) were recruited between 2 and 10 years. The results suggest significant differences in the social scene parsing strategies of children with ASD, giving added insight into the way they may decode and interpret the social scenarios.[N A J Med Sci. 2016;9(3):96-103. DOI: 10.7156/najms.2016.0903096
Functional Analysis Contingencies on Precursors: Response Hierarchy Relationship Hypotheses
Get PDFFunction-based interventions are effective in the treatment of severe problem behaviors. Functional analyses methodologies may present risks associated with behaviors under investigation. Researchers continue to explore alternatives for eliminating these risks. Identification of potential functions of less severe behaviors (i.e., precursors) that reliably precede more severe behavior may facilitate in the development of effective interventions (Smith & Churchill, 2002). In the current study, two experiments were conducted to treat challenging behaviors displayed by a 20-year-old woman with autism. Hypothesized maintaining consequences of precursor to the participant’s more severe behavior (self-injurious behavior; SIB and aggression) were identified in Experiment 1. Prior functional analysis contingencies of the participants SIB and aggression guided the development of a treatment package consisting of differential reinforcement, functional communication training- FCT, extinction, and response interruption and redirection (RIRD). The treatment package was utilized in experiment 2 to treat precursors hypothesized to belong in the same response class as the participant’s SIB and aggression. Results indicated a decrease in the frequency of SIB and aggression suggesting precursor analysis to be a promising alternative for reducing risks associated with FAs. [N A J Med Sci. 2016;9(4):141-150. DOI: 10.7156/najms.2016.0904141] Key Words: functional analysis, FCT, indirect assessments, precursor, self-injurious behavior, extinctio
Ducts of Luschka as a Mimicker of Well-Differentiated Adenocarcinoma of Gallbladder: A Case Report and Review of Literature
Get PDFDucts of Luschka are small bile ducts located at the subserosal or subhepatic connective tissue of gallbladder. These ducts are commonly seen in up to 10% of routine cholecystectomy specimens. When proliferating with reactive changes as seen in the background of acute cholecystitis, they can mimic adenocarcinoma of gallbladder. However, this phenomenon is not well recognized in pathology literature, with only two articles available in English language literature. In this study, we report a case of acute cholecystitis with reactive Ducts of Luschka that is difficult to distinguish from gallbladder adenocarcinoma. We described the clinical and pathologic findings in this case and discussed the morphologic features that are helpful in establishing the correct diagnosis. [N A J Med Sci. 2016;9(4):187-191. DOI: 10.7156/najms.2016.0904187]Key Words: ducts of Luschka, gallbladder adenocarcinom
Update on Treatment of Hepatitis B and Prospects for Possible Cure
No full textSince the discovery of the hepatitis B virus (HBV) 50 years ago, its genome sequence, epidemiology, pathogenesis, and hepatocarcinogenesis have been elucidated. The ultimate goal of treating chronic HBV is prevention of hepatocellular carcinoma (HCC). With the development of HBV vaccine in the 1980’s, the global prevalence of HBV infection has decreased significantly albeit not uniformly. Currently, there are 400 million HBV carriers worldwide. The natural history of HBV intimately involves the host immune system, and the association between HBV and HCC is well-described. With the development of effective antiviral drugs since 1992, disease progression has been retarded along with the reduced need for liver transplantation. In addition, antiviral treatments play an important role in special populations, including pregnant women, patients receiving immunosuppressive therapy, and those undergoing treatment for HCC. Looking to the future, we hope the world would soon witness the cure of hepatitis B.
Dietary Antioxidant Vitamins and Flavonoids and Type 2 Diabetes: A Review of Current Epidemiologic Evidence
Get PDFGiven the increasing incidence of type 2 diabetes, the identification of effective and safe preventive measures that offer even modest reductions in incidence could have a significant public health impact. One promising but as-yet unproven nutritional strategies for the prevention of diabetes or diabetic complications are dietary antioxidants. Several lines of evidence from laboratory research and observational studies has suggested increased oxidative damages on insulin resistance and pancreatic β-cell insulin secretion, indicating a role of oxidative stress in the etiology of type 2 diabetes. Ample non-human experimental evidence has demonstrated that dietary antioxidants such as vitamins C and E and flavonoids, protect against free radical-mediated damage by reducing free oxygen radicals and replenishing antioxidant reserves. While there is a longstanding interest in the diabetes community regarding the promising yet unproven role of antioxidants in the prevention of diabetes and diabetic complications, available human epidemiologic data provide equivocal information. Evidence from prospective cohort studies generally supports an inverse association between dietary, serum, or plasma levels of vitamins C and E and flavonoids and risk of type 2 diabetes. However, available data from randomized controlled trials did not seem to support the antioxidant hypothesis by showing the null effect of vitamins E and C and beta-carotene on type 2 diabetes among initially nondiabetic individuals. In this article, we review the available literature concerning the efficacy of antioxidants from diets or supplements in reducing the risk of type 2 diabetes.
The Emerging Alcoholic Liver Disease in China
Get PDFOver the past a few decades, the pattern of liver diseases in China has been changing. Alcohol abuse is a significant contributor to the global burden of disease and a leading cause of liver disease. Alcoholic liver disease(ALD) is associated with significant morbidity and mortality, which includes a spectrum of disorders from simple steatosis to steatohepatitis, fibrosis, cirrhosis and hepatocellular carcinoma. In China, with the establishment and effective implementation of the Expanded Program on Immunization for HBV from 1992, the number of newly HBV-infected patients had a significant decline; whereas the number of patients with alcoholic and nonalcoholic fatty liver diseases is growing. The incidence of ALD will continue to upsurge in China. Due to significant differences in alcohol metabolism, genetics, drinking patterns, and eating habits and behaviors between the East and the West, the pathogenesis of ALD in Chinese population may be different from the well-characterized ALD in Western countries. In this article, we reviewed and discussed the epidemic trend, the occurrence and the development of ALD in China.[N A J Med Sci. 2016;9(2):55-58. DOI: 10.7156/najms.2016.0902055