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2.
Clin Microbiol Newsl ; 44(22): 199-208, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36438980

ABSTRACT

Monkeypox virus (MPXV) has garnered recent attention as outbreaks are continually reported outside historic regions of endemicity in Africa. Consequently, MPXV is becoming routinely included in the differential diagnosis of rash illnesses, requiring clinicians and laboratorians alike to quickly adapt to a new public health emergency. This review discusses the epidemiology, clinical presentation, and laboratory testing of MPXV in the context of recent outbreaks.

3.
PeerJ ; 9: e12426, 2021.
Article in English | MEDLINE | ID: mdl-34824916

ABSTRACT

BACKGROUND: Ischemia-reperfusion (IR) injury is one of the leading causes of early graft dysfunction in liver transplantation. Techniques such as ischemic preconditioning protect the graft through the activation of the hypoxia-inducible factors (HIF), which are downregulated by the EGLN family of prolyl-4-hydroxylases, a potential biological target for the development of strategies based on pharmacological preconditioning. For that reason, this study aims to evaluate the effect of the EGLN inhibitor sodium (S)-2-hydroxyglutarate [(S)-2HG] on liver IR injury in Wistar rats. METHODS: Twenty-eight female Wistar rats were divided into the following groups: sham (SH, n = 7), non-toxicity (HGTox, n = 7, 25 mg/kg of (S)-2HG, twice per day for two days), IR (n = 7, total liver ischemia: 20 minutes, reperfusion: 60 minutes), and (S)-2HG+IR (HGIR, n = 7, 25 mg/kg of (S)-2HG, twice per day for two days, total liver ischemia as the IR group). Serum ALT, AST, LDH, ALP, glucose, and total bilirubin were assessed. The concentrations of IL-1ß, IL-6, TNF, malondialdehyde, superoxide dismutase, and glutathione peroxidase were measured in liver tissue, as well as the expression of Hmox1, Vegfa, and Pdk1, determined by RT-qPCR. Sections of liver tissue were evaluated histologically, assessing the severity of necrosis, sinusoidal congestion, and cytoplasmatic vacuolization. RESULTS: The administration of (S)-2HG did not cause any alteration in the assessed biochemical markers compared to SH. Preconditioning with (S)-2HG significantly ameliorated IR injury in the HGIR group, decreasing the serum activities of ALT, AST, and LDH, and the tissue concentrations of IL-1ß and IL-6 compared to the IR group. IR injury decreased serum glucose compared to SH. There were no differences in the other biomarkers assessed. The treatment with (S)-2HG tended to decrease the severity of hepatocyte necrosis and sinusoidal congestion compared to the IR group. The administration of (S)-2HG did not affect the expression of Hmox1 but decreased the expression of both Vegfa and Pdk1 compared to the SH group, suggesting that the HIF-1 pathway is not involved in its mechanism of hepatoprotection. In conclusion, (S)-2HG showed a hepatoprotective effect, decreasing the levels of liver injury and inflammation biomarkers, without evidence of the involvement of the HIF-1 pathway. No hepatotoxic effect was observed at the tested dose.

4.
Rev. cir. (Impr.) ; 73(1): 33-38, feb. 2021.
Article in Spanish | LILACS | ID: biblio-1388785

ABSTRACT

Resumen Introducción: Previos trabajos han reportado una asociación entre la infección del virus del papiloma humano (VPH) y el desarrollo de cáncer colorrectal, aunque existe controversia al respecto. Materiales y Método: Estudio observacional, transversal, descriptivo, retrospectivo, no ciego. Se utilizaron 50 muestras de patología con diagnóstico de adenocarcinoma colorrectal, incluidas en parafina, para aislar ADN de las muestras. Se realizó la extracción de ADN mediante protocolos establecidos para extracción, lisis y rehidratación de muestra. Se identificó y genotipicó el ADN del virus para amplificar y detectar subtipos oncogénicos de entre 35 subtipos diferentes incluidos en la prueba, secuenciando las muestras positivas, utilizando protocolos ya establecidos de purificación y análisis de muestra, mediante microarreglos. Resultados: Se identificaron 14 muestras de 50 (28%) estudiadas positivas para el virus de papiloma humano de las cuales 11 (22%) incluyen uno o más subtipos de alto riesgo para neoplasia. No se identificaron diferencias estadísticamente significativas entre grupos en cuanto a edad, sexo, localización del tumor, grado de diferenciación, infiltración, ganglios afectados, metástasis o número de paquetes/año. Conclusión: La detección de los subtipos de VPH de alto riesgo en un alto porcentaje de las muestras positivas, sugiere una asociación entre la infección con el desarrollo de cáncer colorrectal.


Introduction: Previous works have reported an association between human papilloma virus (HPV) infection and the development of colorectal cancer, and although controversy regarding this association exists. Materials and Method: This was an observational, cross-sectional, descriptive, retrospective unblinded study. Fifty pathology samples embedded in paraffin with a diagnosis of colorectal adenocarcinoma were used to isolate DNA from the tissue. DNA was extracted according to established protocols for extraction, lysis and sample rehydration. Viral DNA was identified and genotypified to amplify and detect oncogenic subtypes among 35 different subtypes included in the study, sequencing positive samples with established protocols of purification and sample analysis using microarrays. Results: Fourteen of 50 (28%) samples were identified as positive for human papilloma virus; of these 11 (22%) included one or more high-risk subtypes for neoplasia. Statistically significant differences were not found between the groups regarding age, sex, tumor location, degree of differentiation, infiltration, affected lymph nodes, metastasis and number of pack years. Conclusion: The detection of high-risk VPH subtypes in a high percentage of positive samples, suggests an association between infection and the development of colorectal cancer.


Subject(s)
Humans , Male , Female , Colorectal Neoplasms/virology , Papillomavirus Infections/virology , Papillomaviridae/isolation & purification , Papillomaviridae/genetics , Epidemiology, Descriptive
5.
MedEdPublish (2016) ; 9: 94, 2020.
Article in English | MEDLINE | ID: mdl-38058866

ABSTRACT

This article was migrated. The article was marked as recommended. As the number of graduating medical students increases, the number of primary care residency positions is not keeping pace. One solution to this problem is the creation and accreditation of new residencies, although there is little literature describing the perspectives of the residents and educators who found new programs. Seven out of ten resident physicians who served as the inaugural interns in a new residency training program in pediatrics provide their reflection on the distinctive perspective they had from this experience. They have identified consensus themes in topic areas of strengths, challenges, and lessons learned from training in a new program. Themes applying to strengths of participating in a new residency training program were the opportunity to shape the program, individualized learning experience, and enthusiastic faculty. Challenges of a new program included missing upper level residents, diverse faculty expectations, and morale. Themes under lessons learned included resident engagement, expectations and feedback, and wellness. Each theme was then considered in the context of the medical education literature, underscoring the important balance that new program leaders must strike between structure and flexibility. This inaugural resident class has identified key challenges and opportunities to inform education leaders who are planning new GME training programs.

6.
PLoS Genet ; 13(4): e1006714, 2017 04.
Article in English | MEDLINE | ID: mdl-28419093

ABSTRACT

Microhomology (MH) flanking a DNA double-strand break (DSB) drives chromosomal rearrangements but its role in mutagenesis has not yet been analyzed. Here we determined the mutation frequency of a URA3 reporter gene placed at multiple locations distal to a DSB, which is flanked by different sizes (15-, 18-, or 203-bp) of direct repeat sequences for efficient repair in budding yeast. Induction of a DSB accumulates mutations in the reporter gene situated up to 14-kb distal to the 15-bp MH, but more modestly to those carrying 18- and 203-bp or no homology. Increased mutagenesis in MH-mediated end joining (MMEJ) appears coupled to its slower repair kinetics and the extensive resection occurring at flanking DNA. Chromosomal translocations via MMEJ also elevate mutagenesis of the flanking DNA sequences 7.1 kb distal to the breakpoint junction as compared to those without MH. The results suggest that MMEJ could destabilize genomes by triggering structural alterations and increasing mutation burden.


Subject(s)
DNA End-Joining Repair/genetics , DNA/genetics , Mutagenesis/genetics , Saccharomyces cerevisiae Proteins/genetics , Chromosomes/genetics , DNA Breaks, Double-Stranded/drug effects , DNA-Binding Proteins/genetics , Galactose/genetics , Kinetics , Mutagenesis/drug effects , Mutagenesis, Insertional , Saccharomyces cerevisiae , Translocation, Genetic/drug effects , Translocation, Genetic/genetics
7.
Mutat Res ; 788: 17-24, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26790771

ABSTRACT

Prevalence of microhomology (MH) at the breakpoint junctions in somatic and germ-line chromosomal rearrangements and in the programmed immune receptor rearrangements from cells deficient in classical end joining reveals an enigmatic process called MH-mediated end joining (MMEJ). MMEJ repairs DNA double strand breaks (DSBs) by annealing flanking MH and deleting genetic information at the repair junctions from yeast to humans. Being genetically distinct from canonical DNA DSB pathways, MMEJ is involved with the fusions of eroded/uncapped telomeres as well as with the assembly of chromosome fragments in chromothripsis. In this review article, we will discuss an up-to-date model representing the MMEJ process and the mechanism by which cells regulate MMEJ to limit repair-associated mutagenesis. We will also describe the possible therapeutic gains resulting from the inhibition of MMEJ in recombination deficient cancers. Lastly, we will embark on two contentious issues associated with MMEJ such as the significance of MH at the repair junction to be the hallmark of MMEJ and the relationship of MMEJ to other mechanistically related DSB repair pathways.


Subject(s)
DNA Breaks, Double-Stranded , DNA End-Joining Repair , Models, Genetic , Animals , Cell Cycle/genetics , Cell Survival/genetics , Homologous Recombination , Humans , INDEL Mutation
8.
Stem Cells ; 33(8): 2400-15, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25966666

ABSTRACT

Although mesenchymal stem cells (MSCs) have been implicated as stromal components of several cancers, their ultimate contribution to tumorigenesis and their potential to drive cancer stem cells, particularly in the unique microenvironment of human brain tumors, remain largely undefined. Consequently, using established criteria, we isolated glioma-associated-human MSCs (GA-hMSCs) from fresh human glioma surgical specimens for the first time. We show that these GA-hMSCs are nontumorigenic stromal cells that are phenotypically similar to prototypical bone marrow-MSCs. Low-passage genomic sequencing analyses comparing GA-hMSCs with matched tumor-initiating glioma stem cells (GSCs) suggest that most GA-hMSCs (60%) are normal cells recruited to the tumor (group 1 GA-hMSCs), although, rarely (10%), GA-hMSCs may differentiate directly from GSCs (group 2 GA-hMSCs) or display genetic patterns intermediate between these groups (group 3 GA-hMSCs). Importantly, GA-hMSCs increase proliferation and self-renewal of GSCs in vitro and enhance GSC tumorigenicity and mesenchymal features in vivo, confirming their functional significance within the GSC niche. These effects are mediated by GA-hMSC-secreted interleukin-6, which activates STAT3 in GSCs. Our results establish GA-hMSCs as a potentially new stromal component of gliomas that drives the aggressiveness of GSCs, and point to GA-hMSCs as a novel therapeutic target within gliomas.


Subject(s)
Cell Proliferation , Cytokine Receptor gp130/metabolism , Glioma/metabolism , Interleukin-6/metabolism , Mesenchymal Stem Cells/metabolism , STAT3 Transcription Factor/metabolism , Signal Transduction , Female , Glioma/pathology , Humans , Male , Mesenchymal Stem Cells/pathology
9.
Am J Med Genet A ; 161A(12): 3121-5, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24115482

ABSTRACT

We present a Hispanic male with the clinical and molecular diagnosis of Simpson-Golabi-Behmel syndrome (SGBS). The patient was born with multiple anomalies not entirely typical of SGBS patients, including penoscrotal hypospadias, a large prostatic utricle, and left coronal craniosynostosis. In addition, he demonstrated endocrine anomalies including a low random cortisol level suspicious for adrenal insufficiency and low testosterone level. To our knowledge, this is the first report of a prostatic utricle in SGBS and the second report of craniosynostosis. The unique disease-causing mutation likely arose de novo in the mother. It is a deletion-insertion that leads to a frameshift at the p.p. S359 [corrected] residue of GPC3 and a premature stop codon after five more amino acids. p. S359 [corrected] is the same residue that is normally cleaved by the Furin convertase, although the significance of this novel mutation with respect to the patient's multiple anomalies is unknown. We present this case as the perinatal course of a patient with unique features of SGBS and a confirmed molecular diagnosis.


Subject(s)
Arrhythmias, Cardiac/genetics , Genetic Diseases, X-Linked/genetics , Gigantism/genetics , Glypicans/genetics , Heart Defects, Congenital/genetics , Intellectual Disability/genetics , Prostate/physiopathology , Saccule and Utricle/physiopathology , Abnormalities, Multiple/genetics , Abnormalities, Multiple/physiopathology , Adult , Arrhythmias, Cardiac/complications , Arrhythmias, Cardiac/diagnosis , Arrhythmias, Cardiac/physiopathology , Craniosynostoses/complications , Craniosynostoses/genetics , Craniosynostoses/physiopathology , Disorders of Sex Development/complications , Disorders of Sex Development/genetics , Disorders of Sex Development/physiopathology , Female , Frameshift Mutation , Genetic Diseases, X-Linked/complications , Genetic Diseases, X-Linked/diagnosis , Genetic Diseases, X-Linked/physiopathology , Gigantism/complications , Gigantism/diagnosis , Gigantism/physiopathology , Heart Defects, Congenital/complications , Heart Defects, Congenital/diagnosis , Heart Defects, Congenital/physiopathology , Humans , Infant, Newborn , Intellectual Disability/complications , Intellectual Disability/diagnosis , Intellectual Disability/physiopathology , Male , Pathology, Molecular , Penis/abnormalities , Penis/physiopathology , Scrotum/abnormalities , Scrotum/physiopathology , Urethral Diseases/complications , Urethral Diseases/genetics , Urethral Diseases/physiopathology
10.
PLoS Genet ; 8(11): e1003026, 2012.
Article in English | MEDLINE | ID: mdl-23144625

ABSTRACT

Chromosomal structural change triggers carcinogenesis and the formation of other genetic diseases. The breakpoint junctions of these rearrangements often contain small overlapping sequences called "microhomology," yet the genetic pathway(s) responsible have yet to be defined. We report a simple genetic system to detect microhomology-mediated repair (MHMR) events after a DNA double-strand break (DSB) in budding yeast cells. MHMR using >15 bp operates as a single-strand annealing variant, requiring the non-essential DNA polymerase subunit Pol32. MHMR is inhibited by sequence mismatches, but independent of extensive DNA synthesis like break-induced replication. However, MHMR using less than 14 bp is genetically distinct from that using longer microhomology and far less efficient for the repair of distant DSBs. MHMR catalyzes chromosomal translocation almost as efficiently as intra-chromosomal repair. The results suggest that the intrinsic annealing propensity between microhomology sequences efficiently leads to chromosomal rearrangements.


Subject(s)
DNA Breaks, Double-Stranded , DNA End-Joining Repair , DNA Replication/genetics , Translocation, Genetic/genetics , Chromosome Aberrations , Chromosomes/metabolism , DNA Repair , DNA-Binding Proteins , DNA-Directed DNA Polymerase/genetics , DNA-Directed DNA Polymerase/metabolism , Recombination, Genetic , Saccharomyces cerevisiae
11.
J Agric Food Chem ; 57(23): 11321-7, 2009 Dec 09.
Article in English | MEDLINE | ID: mdl-19908899

ABSTRACT

In a previous study, the effectiveness of chlorogenic acids, fatty acids (FA), and elements was compared for the discrimination of Arabica varieties and growing terroirs. Since FA provided the best results, the aim of the present work was to validate their discrimination ability using an extended experimental design, including twice the number of location x variety combinations and 2 years of study. It also aimed at understanding how the environment influences FA composition through correlation analysis using different climatic parameters. Percentages of correct classification of known samples remained very high, independent of the classification criterion. However, cross-validation tests across years indicated that prediction of unknown locations was less efficient than that of unknown genotypes. Environmental temperature during the development of coffee beans had a dramatic influence on their FA composition. Analysis of climate patterns over years enabled us to understand the efficient location discrimination within a single year but only moderate efficiency across years.


Subject(s)
Coffea/chemistry , Coffea/genetics , Ecosystem , Fatty Acids/analysis , Coffea/growth & development , Genotype , Temperature
12.
Cuenca; s.n; 2009. 51 p. ilus, tab.
Thesis in Spanish | LILACS | ID: lil-626098

ABSTRACT

Determinar la prevalencia de ideación suicida y factores asociados en adolescentes de los colegios urbanos de la ciudad de Cuenca. Materiales y métodos: se realizó un estudio transversal en 755 adolescentes escolarizados de 12 a 19 años. La muestra fue por conglomerados. Los instrumentos utilizados fueron Escala de Ideación Suicida y APGAR familiar. Se realizó análisis univariado y bivariado. Resultados: la prevalencia de ideación suicida en los adolescentes fue de 39.3%. La prevalencia de ideación suicida leve fue 24.8%, moderada 9.3% y grave 5.3%. La disfuncionalidad familiar (OR 4.029 IC 2.89-5.60) y la migración materna (OR 1.96 IC 1.187-3.237) resultaron ser factores de riesgo para la ideación suicida. La migración del padre (OR 1.063 IC 0.747-1.514) y etapa de la adolescencia no resultaron estar asociados a ideación suicida. Conclusiones: existe una alta prevalencia de ideación suicida en adolescentes de los colegios urbanos en la ciudad de Cuenca y está asociada a migración materna y disfuncionalidad familiar. Es pertinente la aplicación de urgentes programas de intervención para mejorar la salud mental de los y las adolescentes.


Subject(s)
Suicide, Attempted/trends , Prevalence
13.
Microbes Infect ; 10(3): 269-75, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18321750

ABSTRACT

Population genetic structure and subdivision are key factors affecting the evolution of organisms. In this study, we analysed and compared the population genetic structure of the malaria parasite Plasmodium falciparum and its mosquito vector Anopheles gambiae over space and time in the Nianza Province, near Victoria Lake in Kenya. The parasites were collected from mosquitoes caught in six villages separated by up to 68 km in 2002 and 2003. A total of 545 oocysts were dissected from 122 infected mosquitoes and genotyped at seven microsatellite markers. Five hundred and forty-seven mosquitoes, both infected and uninfected, were genotyped at eight microsatellites. For the parasite and the vector, the analysis revealed no (or very little) genetic differentiation among villages. This may be explained by high local population sizes for the parasite and the mosquito. The small level of genetic differentiation observed between populations may explain the speed at which antimalarial drug resistance and insecticide resistance spread into the African continent.


Subject(s)
Anopheles/genetics , Insect Vectors/genetics , Plasmodium falciparum/genetics , Animals , Anopheles/parasitology , Genetics, Population , Kenya/epidemiology , Malaria/prevention & control , Microsatellite Repeats/genetics , Oocytes
14.
J Agric Food Chem ; 56(6): 2273-80, 2008 Mar 26.
Article in English | MEDLINE | ID: mdl-18303823

ABSTRACT

The objective of this work was to compare the effectiveness of three chemical families, namely, chlorogenic acids, fatty acids, and elements, for the discrimination of Arabica varieties (traditional versus modern introgressed lines) and potential terroirs within a given coffee-growing area. The experimental design included three Colombian locations in full combination with five (one traditional and four introgressed) Arabica varieties and two field replications. Chlorogenic acids, fatty acids, and elements were analyzed in coffee bean samples by HPLC, GC, and ICP-AES, respectively. Principal component analysis and discriminant analysis were carried out to compare the three methods. Although elements provided an excellent classification of the three locations studied, this chemical class was useless for Arabica variety discrimination. Chlorogenic acids gave satisfactory results, but fatty acids clearly offered the best results for the determination of both varieties and environments, with very high percentages of correct classification (79 and 90%, respectively).


Subject(s)
Chlorogenic Acid/analysis , Coffea/chemistry , Coffea/classification , Fatty Acids/analysis , Seeds/chemistry , Seeds/classification , Chromatography, Gas , Chromatography, High Pressure Liquid , Coffea/growth & development , Colombia , Discriminant Analysis , Environment
15.
Antimicrob Agents Chemother ; 49(7): 2701-9, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15980339

ABSTRACT

We analyzed the differential gene expression among representative Trypanosoma cruzi stocks in relation to benznidazole exposures using a random differentially expressed sequences (RADES) technique. Studies were carried out with drug pressure both at the natural susceptibility level of the wild-type parasite (50% inhibitory concentration for the wild type) and at different resistance levels. The pattern of differential gene expression performed with resistant stocks was compared to the population structure of this parasite, established by random amplified polymorphic DNA analysis and multilocus enzyme electrophoresis. A RADES band polymorphism was observed, and over- or underexpression was linked to the resistance level of the stock. The analysis of RADES bands suggested that different products may be involved in benznidazole resistance mechanisms. No significant association was found between phylogenetic clustering and benznidazole susceptibility. Benznidazole resistance may involve several mechanisms, depending on the level of drug exposure.


Subject(s)
Drug Resistance , Gene Expression Regulation , Nitroimidazoles/pharmacology , Protozoan Proteins/metabolism , Trypanocidal Agents/pharmacology , Trypanosoma cruzi/drug effects , Animals , Electrophoresis/methods , Enzymes/genetics , Gene Expression Profiling , Humans , Molecular Sequence Data , Parasitic Sensitivity Tests , Polymerase Chain Reaction/methods , Protozoan Proteins/genetics , Random Amplified Polymorphic DNA Technique , Sequence Analysis, DNA , Trypanosoma cruzi/genetics , Trypanosoma cruzi/growth & development
16.
Exp Parasitol ; 108(1-2): 24-31, 2004.
Article in English | MEDLINE | ID: mdl-15491545

ABSTRACT

Chagas disease remains an important health problem in Central and South America. Nitroimidazole derivative drugs like Benznidazole are commonly used to treat Trypanosoma cruzi infection. Natural variation of drug susceptibility between various T. cruzi stocks has been proposed as a possible explanation of treatment failure. Thus, the aim of this work was to determine potential correlations between in vitro Benznidazole susceptibility of different T. cruzi stocks and their genetic diversity. For this purpose, 16 natural stocks representing the overall genetic diversity of the parasite were analysed. Genetic characterisation was assessed by both random amplified polymorphic DNA (RAPD) and multilocus enzyme electrophoresis (MLEE) analyses. Drug activity was determined by two complementary methods, the MTT-PMS micro-method and FACs analysis. The 50% inhibitory concentrations (IC(50)s) were determined. Important variation of IC(50) values (7.3-16.9 microM) among stocks belonging to different discrete typing units (DTUs) was recorded. Further, correlation analysis showed that natural susceptibility to Benznidazole in T. cruzi expressed as IC(50) level was not related with its genetic structure represented by the different DTUs. These results are discussed in relation with the proposed hypothesis establishing a link between genetic diversity and biological behaviour in T. cruzi.


Subject(s)
Genetic Variation , Nitroimidazoles/pharmacology , Trypanocidal Agents/pharmacology , Trypanosoma cruzi/classification , Trypanosoma cruzi/drug effects , Analysis of Variance , Animals , Chagas Disease/drug therapy , Chagas Disease/parasitology , Electrophoresis, Cellulose Acetate , Flow Cytometry , Humans , Inhibitory Concentration 50 , Isoenzymes/analysis , Isoenzymes/genetics , Parasitic Sensitivity Tests , Phylogeny , Random Amplified Polymorphic DNA Technique , Trypanosoma cruzi/enzymology , Trypanosoma cruzi/genetics
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