Prevalence of amoebiasis and associated risk factors among population in Duhok city, Kurdistan Region, Iraq.

INTRODUCTION: Entamoeba histolytica, a protozoan parasite, is the third major contributor to human mortality and morbidity outside of malaria and schistosomiasis. The purpose of this cross-sectional study was to estimate the prevalence of Entamoeba spp. among outpatients of two teaching hospitals in Duhok city who agreed to participate in the study from April 2021 to March 2022 to assess the impact of associated risk variables on the infection rate. METHODOLOGY: Stool specimens were collected from outpatients suffering from diarrhea and other gastrointestinal symptoms in two teaching hospitals: Azadi and Heevi Pediatric in Duhok city, Kurdistan Region- Iraq. The collected stool specimens were examined macroscopically, followed by microscopic examination using the direct wet mount and zinc sulfate flotation methods, respectively. RESULT: Infection with Entamoeba species was recorded in 21.68% (562/2592) of the analyzed specimens. Males had a significantly higher infection rate than females (67.43% vs. 32.56%). This difference was statistically significant (p < 0.000). The highest rate was seen in the age group 1-10 years (p < 0.001). Lower levels of education, low incomes, eating unwashed fruits and vegetables, drinking well water, eating frequently outside of homes, not using antidiarrheal medications and living in overcrowded families were risk factors that showed high levels of infection (p < 0.0001). CONCLUSIONS: The present study concluded that improving living conditions, providing clean water, and promoting health education programs are essential to reduce the rate of this disease among the population.

Experience of treating pediatric hepatoblastoma at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia - Timely surgical intervention playing a key role.

BACKGROUND: Many studies have demonstrated that outcome in patients with hepatoblastoma is determined by tumor resectability and the presence or absence of metastatic disease. PURPOSE: To evaluate and disseminate information on diagnosis, treatment, and outcome of hepatoblastoma patients at a tertiary care hospital in Saudi Arabia. PATIENTS AND METHODS: Twenty-four pediatric patients with hepatoblastoma were treated at our institution between January 2005 and December 2012. The majority of our patients were stage III and above, while one-third of them presented with metastatic disease. Four (16.7%) had vascular invasion. Two-thirds of our patients (n = 16, 66.7%) had alpha-fetoprotein (AFP) level above 100,000 ng/mL. Twenty-one patients underwent surgery; two had upfront surgery before getting any chemotherapy, and 15 had surgery on schedule after pre-operative chemotherapy. Four patients had delayed surgery as the tumor was not resectable and received extra cycles of chemotherapy. Chemotherapy regimens used were based on SIOPEL study protocols until 2011 and Children's Oncology Group (COG) protocol from 2012 onwards. Relapse, progressive disease, or death from any cause were defined as events. RESULTS: Five-year overall survival (OS) of the cohort over a median follow-up time of 56.1 months was 70.6% ± 9.4% with seven (29.2%) events of mortality. No significant difference was found for age at diagnosis (less than 2 years vs. more), stage of disease, AFP levels (less than 100,000 vs. more), vascular invasion, or presence of metastatic disease at presentation in terms of OS. However, children receiving upfront or scheduled as-per-protocol surgery fared better than those who had delayed surgery (as the tumor was not resectable and they received extra cycles of chemotherapy) or did not undergo any surgery (P-Value .001). CONCLUSION: Favorable survival outcome could be achieved with complete tumor excision and adjuvant chemotherapy. Inability to perform surgical excision was the single most important predictor of mortality in our patients.

Dental Practice Infection Control Measurements: Coronavirus Disease (COVID-19) Outbreaks.

A new coronavirus disease called COVID-19 has been considered to be a public health emergency of international apprehension by the WHO. This new disease includes multiple symptoms such as fever, cough, sore throat, and rhinorrhea. The disease is mild in most people; however, in some patients, it may develop to pneumonia, acute respiratory distress syndrome (ARDS), and multiple dysfunctions in the organs which may lead to death. There are two routes of transmission for this virus, the first route is the direct transmission, through cough or droplet inhalation, while the second route is through contact, for example, contact with oral and nasal mucous membranes; consequently, extensive and intensive measures should be taken to decrease the transmission of COVID-19 from person to person. Due to the nature of dental work and its procedures, the dental professionals are in a high risk of transmission. Hence, in this article, we wanted to highlight the clinical features, trajectories of spread, and infection control considerations to prevent and control the spread of this fatal disease. HOW TO CITE THIS ARTICLE: Ayyed AB. Dental Practice Infection Control Measurements: Coronavirus Disease (COVID-19) Outbreaks. Int J Clin Pediatr Dent 2020;13(3):279-283.

Deciphering the Evolutionary History of Arowana Fishes (Teleostei, Osteoglossiformes, Osteoglossidae): Insight from Comparative Cytogenomics.

Arowanas (Osteoglossinae) are charismatic freshwater fishes with six species and two genera (Osteoglossum and Scleropages) distributed in South America, Asia, and Australia. In an attempt to provide a better assessment of the processes shaping their evolution, we employed a set of cytogenetic and genomic approaches, including i) molecular cytogenetic analyses using C- and CMA3/DAPI staining, repetitive DNA mapping, comparative genomic hybridization (CGH), and Zoo-FISH, along with ii) the genotypic analyses of single nucleotide polymorphisms (SNPs) generated by diversity array technology sequencing (DArTseq). We observed diploid chromosome numbers of 2n = 56 and 54 in O. bicirrhosum and O. ferreirai, respectively, and 2n = 50 in S. formosus, while S. jardinii and S. leichardti presented 2n = 48 and 44, respectively. A time-calibrated phylogenetic tree revealed that Osteoglossum and Scleropages divergence occurred approximately 50 million years ago (MYA), at the time of the final separation of Australia and South America (with Antarctica). Asian S. formosus and Australian Scleropages diverged about 35.5 MYA, substantially after the latest terrestrial connection between Australia and Southeast Asia through the Indian plate movement. Our combined data provided a comprehensive perspective of the cytogenomic diversity and evolution of arowana species on a timescale.

54-cm enteric duplication cyst in a 13-year-old female.

Enteric duplication cyst is a very rare condition, the affected individual may be asymptomatic. It has serious complications, on top of which is a malignant transformation tendency. To avoid these complications, resection of the duplication seems to be mandatory, even if it is an incidental finding.

Early Stages of XY Sex Chromosomes Differentiation in the Fish Hoplias malabaricus (Characiformes, Erythrinidae) Revealed by DNA Repeats Accumulation.

BACKGROUND: Species with 'young' or nascent sex chromosomes provide unique opportunities to understand early evolutionary mechanisms (e.g. accumulation of repetitive sequences, cessation of recombination and gene loss) that drive the evolution of sex chromosomes. Among vertebrates, fishes exhibit highly diverse and a wide spectrum of sex-determining mechanisms and sex chromosomes, ranging from cryptic to highly differentiated ones, as well as, from simple to multiple sex chromosome systems. Such variability in sex chromosome morphology and composition not only exists within closely related taxa, but often within races/populations of the same species. Inside this context, the wolf fish Hoplias malabaricus offers opportunity to investigate the evolution of morphologically variable sex chromosomes within a species complex, as homomorphic to highly differentiated sex chromosome systems occur among its different karyomorphs. MATERIALS & METHODS: To discover various evolutionary stages of sex chromosomes and to compare their sequence composition among the wolf fish´s karyomorphs, we applied multipronged molecular cytogenetic approaches, including C-banding, repetitive DNAs mapping, Comparative Genomic Hybridization (CGH) and Whole Chromosomal Painting (WCP). Our study was able to characterize a cryptically differentiated XX/XY sex chromosome system in the karyomorph F of this species. CONCLUSION: The Y chromosome was clearly identified by an interstitial heterochromatic block on the short arms, primarily composed of microsatellite motifs and retrotransposons. Additionally, CGH also identified a male specific chromosome region in the same chromosomal location, implying that the accumulation of these repeats may have initiated the Y chromosome differentiation, as well as played a critical role towards the evolution and differentiation of sex chromosomes in various karyomorphs of this species.

Tracking the evolutionary pathway of sex chromosomes among fishes: characterizing the unique XX/XY1Y2 system in Hoplias malabaricus (Teleostei, Characiformes).

The Neotropical fish, Hoplias malabaricus, is one of the most cytogenetically studied fish taxon with seven distinct karyomorphs (A-G) comprising varying degrees of sex chromosome differentiation, ranging from homomorphic to highly differentiated simple and multiple sex chromosomes. Therefore, this fish offers a unique opportunity to track evolutionary mechanisms standing behind the sex chromosome evolution and differentiation. Here, we focused on a high-resolution cytogenetic characterization of the unique XX/XY1Y2 multiple sex chromosome system found in one of its karyomorphs (G). For this, we applied a suite of conventional (Giemsa-staining, C-banding) and molecular cytogenetic approaches, including fluorescence in situ hybridization FISH (with 5S and 18S rDNAs, 10 microsatellite motifs and telomeric (TTAGGG) n sequences as probes), comparative genomic hybridization (CGH), and whole chromosome painting (WCP). In addition, we performed comparative analyses with other Erythrinidae species to discover the evolutionary origin of this unique karyomorph G-specific XY1Y2 multiple sex chromosome system. WCP experiments confirmed the homology between these multiple sex chromosomes and the nascent XX/XY sex system found in the karyomorph F, but disproved a homology with those of karyomorphs A-D and other closely related species. Besides, the putative origin of such XY1Y2 system by rearrangements of several chromosome pairs from an ancestral karyotype was also highlighted. In addition, clear identification of a male-specific region on the Y1 chromosome suggested a differential pattern of repetitive sequences accumulation. The present data suggested the origin of this unique XY1Y2 sex system, revealing evidences for the high level of plasticity of sex chromosome differentiation within the Erythrinidae.

Generation of multicolor banding probes for chromosomes of different species.

BACKGROUND: The multicolor banding (MCB/mBAND) technique provides a unique opportunity to characterize intrachromosomal rearrangements and to determine chromosomal breakpoints. Until recently, MCB probes have only been available for human and some murine chromosomes. Generation of MCB probes for chromosomes of other species, useful and required in many cytogenetics research fields, was limited by technical difficulties. MCB probes are established by chromosome microdissection followed by whole genomic DNA amplification. However, unambiguous identification of the target chromosome is required for MCB-probe establishment. Previously proposed protocols suggested G-banding staining or preliminary FISH with whole chromosome paints (WCP) as methods to identify the chromosome of interest. RESULTS: Here we present a complete workflow for MCB probe generation for those cases and species where chromosome morphology is too challenging to recognize target chromosomes by conventional methods and where WCP probes are not available. The workflow was successfully applied for murine chromosomes that are difficult to identify unambiguously. Additionally, we showed that glass-needle based microdissection enables establishment of a whole set of WCP paints by microdissection of individual chromosomes of a single metaphase CONCLUSIONS: The present method can be applied for generation of whole or region-specific DNA probes for species, where karyotyping of G-banded chromosomes is challenging due to similar chromosome morphology and/or chromosome banding patterns.

Small supernumerary marker chromosomes 1 with a normal phenotype.

Small supernumerary marker chromosomes (sSMCs) are a major problem in prenatal cytogenetic diagnostics. Over two-thirds of cases carrying an sSMC derived from chromosome 1 are associated with clinical abnormalities. We report 3 further cases of such sSMCs that did not show any clinical abnormalities. All 3 sSMCs studied were detected prenatally and characterized comprehensively for their genetic content by molecular cytogenetics using subcentromere-specific multicolor fluorescence in situ hybridization, and for a possibly associated uniparental disomy. After exclusion of additional euchromatin due to the presence of sSMCs and a uniparental disomy, parents opted for continuation of the pregnancies and healthy children were born in all 3 cases. It is important to quickly and clearly characterize prenatal sSMCs. Also, all available sSMC cases need to be collected on a homepage such as the Jena Institute of Human Genetics and Anthropology sSMC homepage (http://www.med.uni-jena.de/fish/sSMC/00START.htm).

Presence of harmless small supernumerary marker chromosomes hampers molecular genetic diagnosis: a case report.

Mental retardation is correlated in approximately 0.4% of cases with the presence of a small supernumerary marker chromosome (sSMC). However, here we report a case of a carrier of a heterochromatic harmless sSMC with fragile X syndrome (Fra X). In approximately 2% of sSMC cases, similar heterochromatic sSMC were observed in a clinically abnormal carriers. In a subset of such cases, uniparental disomy (UPD) of the corresponding sister chromosomes was shown to be the cause of mental retardation. For the remainder of the cases, including the present one, the sSMC was just a random finding not related to the clinical phenotype. Thus, it is proposed to test patients with heterochromatic sSMC and mental retardation of unclear cause as follows: i) exclude UPD, ii) test for Fra X as it is a major cause of inherited mental retardation, and iii) perform chip-based assays or tests for special genetic diseases according to the phenotype. In any case, the diagnosis of a cytogenetic aberration such as an sSMC should not automatically be considered the resolution of a clinical case.