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1.
Ann Transplant ; 29: e942188, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38225813

RESUMEN

BACKGROUND The COVID-19 pandemic had multifaceted and disproportionate impacts on various countries. We investigated the decline of heart and kidney transplantation in 2020 and recovery trends in 2020, 2021, and 2022 in 30 developed and developing countries, considering COVID-19 incidence and mortality and pandemic-time economic variables. MATERIAL AND METHODS Data were obtained from reliable open databases. Nations were grouped by hierarchical cluster analysis into high-gross domestic product (GDP), mid-GDP, and low-GDP countries. Expected transplant numbers for 2020 to 2021 were estimated by the artificial neural network method using data from 2015 to 2019. Effect size and its inference were determined through the Hodges-Lemann estimate and Wilcoxon signed-rank test, respectively. The possible disproportionate effect was estimated by the Jonckheere-Tersptra test. Associations between transplantation and economic variables, COVID-19 caseload, and mortality were examined using Kendall rank correlation analysis. RESULTS All nations experienced a decline in 2020 and some real recovery in 2020 to 2022. For high-GDP countries, decline was insignificant and recovery was marginal; for mid-GDP countries, decline was significant for heart and deceased kidneys and recovery was modest; for low-GDP countries, decline was significant for heart, live kidneys, and deceased kidneys and recovery was marginal. The low-GDP countries were disproportionally negatively impacted, although the associations between the impact and economic variables, COVID-19 incidence, and COVID-19 mortality were statistically insignificant. CONCLUSIONS More inclusive studies of socioeconomic and cultural factors that affected the impact of the COVID-19 pandemic in different countries can be useful for better preparedness and reducing disruption in healthcare in future global pandemics.


Asunto(s)
COVID-19 , Trasplante de Corazón , Trasplante de Riñón , Humanos , COVID-19/epidemiología , Países en Desarrollo , Pandemias
2.
Prostate Cancer ; 2020: 5959134, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32089890

RESUMEN

BACKGROUND: Angiotensin I converting enzyme (ACE) insertion (I) and 287 bp Alu repeat DNA fragment deletion (D) polymorphisms have been indicated in various cancers. Here, we investigated I/D polymorphisms in prostate cancer (PCa) and benign prostate hyperplasia (BPH) among Lebanese men. METHODS: Blood DNA extracted from 69 control subjects, 69 subjects with clinically confirmed PCa, and 69 subjects with clinical BPH, all the subjects were aged 50 years or older, was subjected to the polymerase chain reaction. The PCR products were resolved in polyacrylamide gels to determine II, ID, and DD genotypes. The odds ratios (OR), 95% confidence intervals (CI), and p values of the allele frequencies and genotype ratios were calculated for establishing possible association of the alleles and/or genotypes and PCa and/or BPH. RESULTS: The proportions of II, ID, and DD genotypes were significantly different from Hardy-Weinberg equilibrium for BPH and PCa groups (but not the control group), mostly due to overabundance of the ID genotypes. There was no significant difference in the I and D allele frequencies between the control groups and the affected groups. The ratio of (DD + ID)/II is significantly lower among the control group compared to the BPH group (RR = 8.92, p values of the allele frequencies and genotype ratios were calculated for establishing possible association of the alleles and/or genotypes and PCa and/or BPH. p values of the allele frequencies and genotype ratios were calculated for establishing possible association of the alleles and/or genotypes and PCa and/or BPH. CONCLUSIONS: Our data indicate that the D allele of the I/D polymorphisms of the ACE gene is associated with increased risk of BPH, and the ID genotype is a risk factor for both BPH and PCa among Lebanese males.

3.
Transplant Proc ; 52(1): 12-19, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31917000

RESUMEN

BACKGROUND: A severe shortage in donor organs is the major driver for organ transplantation-related crimes. The Declaration of Istanbul 2008 (DOI) was created to stop such crimes. We investigated the impact of DOI on Internet reporting of transplantation-related crimes. METHODS: We conducted Google Advanced Searches to collect data on "kidney trade," "kidney sale," "organ trafficking," and "transplant tourism" in 15 original participant and 10 nonparticipant countries, 6 years prior through 8 years after the promulgation of DOI. The data were normalized for population and transformed to a logarithmic scale. Interrupted time series analysis (ITSA) was applied to estimate the changes in slopes of the outcome variables before and after DOI, and then the overall intervention impact was calculated by meta-analysis. RESULTS: The combined results indicated that the overall impact of DOI on the reporting of "organ trafficking" and "transplant tourism" was statistically negative (reporting reduced significantly) as intended but on "kidney sale" and "kidney trade" was statistically positive (reporting increased significantly), and the increase was higher in the nonparticipant countries compared to the participant countries. The rate of reporting on "transplant tourism" declined in the participant countries more pronouncedly than in the nonparticipant countries. CONCLUSIONS: DOI has a positive impact on the reporting of "organ trafficking" and "transplant tourism" but not on the reporting of "kidney sale" and "kidney trade." The increased reporting of "kidney sale" and "kidney trade" can be indicative of an impact of DOI on public awareness and increased reporting of the residual transplantation-related crimes.


Asunto(s)
Política de Salud , Internet/tendencias , Tráfico de Órganos/legislación & jurisprudencia , Tráfico de Órganos/prevención & control , Tráfico de Órganos/tendencias , Humanos , Análisis de Series de Tiempo Interrumpido , Riñón , Turismo Médico/legislación & jurisprudencia , Turismo Médico/tendencias , Trasplante de Órganos/legislación & jurisprudencia
4.
Asian Pac J Cancer Prev ; 18(1): 93-100, 2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28240015

RESUMEN

Aims: The goal of the study was to investigate possible association of some single nucleotide polymorphisms (SNPs) in the VDR gene (the FokI, BsmI, ApaI and TaqαI loci), and the CYP17 gene (the MspA1I locus), and 0 or 9 TA repeats in the SRD5A2 gene, and prostate cancer (PCa) among Lebanese men. Materials and Methods: Blood DNA of 69 subjects with confirmed PCa and 69 controls, all about 50 years of age or older, was subjected to PCR or PCR-restriction fragment-length polymorphism (PCR-RFLP) analyses, and the risk-bearing and the protective alleles were identified. The odds ratio (OR) of having a genotype and the relative risk (RR) of developing PCa were calculated. In addition, the distributions of homozygosis and heterozygosis in the risk-bearing alleles and the protective alleles among the control and the PCa groups were compared. Results: The f allele of the VDR FokI locus and the (TA) 9 repeat allele of the SRD5A2 gene were found to be associated with increased risks of PCa (p = 0.006 and 0.050, respectively). Homozygosis in the risk-bearing alleles was rare both in the control and the PCa groups. A higher fraction of the controls compared to the PCa group was double-homozygous in the two protective alleles (52.2% for controls, 24.6% for PCa group, p = <0.001). Conclusions: To the best of our knowledge, this is the first genetic study demonstrating the association of certain polymorphisms of the VDR gene and the SDR5A2 gene and increased risk of PCa among Lebanese men. Our study also indicates that the overall polymorphism profile of all genes involved in the prostate physiology is likely to be a better indicator for PCa risk than the polymorphisms in the individual genes.

5.
Asian Pac J Cancer Prev ; 16(8): 3493-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25921167

RESUMEN

OBJECTIVE: To assess associations between codon 72 polymorphisms (Pro or B and Arg or b alleles) of the TP53 gene and lung cancer risk among Bangladeshis. MATERIALS AND METHODS: The distribution of the BB, Bb, and bb genotypes and the frequencies of the B and b alleles were determined by PCR-RFLP method using DNA extracted from leucocytes of 50 confirmed lung cancer patients and 50 age-matched controls and the data were analysed. RESULTS: The ratio of BB, Bb, and bb genotypes were in Hardy-Weinberg equilibrium except for the male patients (χ2=4.6). The B allele is overrepresented among all patients (OR=2.0, p=0.02) and the female patients (OR=4.1, p≤0.01) compared to the controls. The BB/bb ratio was also higher among the patients (OR=3.0, p=0.03). The relative risk of cancer for having BB over bb genotype was 1.8 (p=0.04) but no effect was observed for the Bb genotype. The B allele was overrepresented among patients with adenocarcinomas (OR=2.4, p≤0.01) and squamous cell carcinomas (OR=2.7, p≤0.01) over the controls but the difference was not significant for those with small cell lung carcinomas (OR=1.1, p=0.66). The B allele was overrepresented among patients age 50 or younger (OR=2.7, p≤0.01), but not for older patients (OR=1.7, p=0.07), and among smokers compared to the controls (OR=1.8-10.0, p≤0.01-0.03). However, no correlation between increasing pack-years and lung cancer was observed. CONCLUSIONS: The Pro/Pro (BB) genotype and the B allele are risk factors for lung cancer among Bangladeshis, particularly for people under age 50, women and smokers.


Asunto(s)
Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , Neoplasias Pulmonares/genética , Fumar , Proteína p53 Supresora de Tumor/genética , Adulto , Factores de Edad , Anciano , Bangladesh , Estudios de Casos y Controles , Codón , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Factores Sexuales
6.
Pediatr Int ; 52(4): 631-9, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20202157

RESUMEN

BACKGROUND: Congenital hypothyroidism is screened using blood spotted on filter paper that may be transported from remote areas to central testing facilities. However, storage conditions and transportation may affect sample quality. METHODS: We examined long-term stability of thyroid-stimulating hormone (TSH) and thyroxin (TT4) in blood spotted on filter paper, which was stored at room temperature (RT), 4°C and -20°C under continuous or intermittent power supply (six hours on and six hours off around the clock.) Hormone levels in the discs were measured periodically for up to ten years. Extraction of DNA from blood spots and polymerase chain reaction were performed. RESULTS: Our results showed that TT4 was stable for up to 6.1, 5.34 and 5.16 years when stored at -20°C, 4°C and RT, respectively. TSH was stable for up to 2.7 years at RT, and for up to 6.5 and 4.1 years when stored at -20°C and 4°C, respectively, under continuous power supply. However, under intermittent power supply, TSH was stable for up to 3.8 and 2.5 years when stored at 4°C and -20°C, respectively. Mitochondrial cytochrome oxidase and sex-determining region of Y chromosome genes were successfully amplified from DNA extracted from the blood spots. CONCLUSION: Our data indicate that TT4 and TSH are most stable in blood spots stored at -20°C under continuous power supply. However, they can be stored at RT or at 4°C and -20°C under interrupted power supply for at least 2.5 years. Moreover, the DNA extracted from the blood spots was intact and suitable for genetic studies.


Asunto(s)
Recolección de Muestras de Sangre , Hipotiroidismo Congénito/diagnóstico , ADN/sangre , Tirotropina/sangre , Tiroxina/sangre , Computadoras de Mano , Hipotiroidismo Congénito/sangre , Humanos , Radioinmunoensayo , Manejo de Especímenes , Temperatura
7.
J Virol ; 81(17): 9230-7, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17581987

RESUMEN

The human herpes simplex virus type 1 regulatory protein ICP4 binds DNA as a dimer and forms a single protein-DNA complex (A complex) with short DNA probes. ICP4 oligomerized in a DNA-dependent manner, forming two or more protein-DNA complexes with longer DNA fragments containing a single DNA binding site. When resolved electrophoretically, one or more low-mobility DNA-protein complexes follow the fast-moving A complex. The major protein-DNA complex (B complex) formed by ICP4 with long DNA probes migrates just behind the A complex in the electric field, implying the oligomerization of ICP4 on the DNA. Binding experiments with circularly permutated DNA probes containing one ICP4 binding site revealed that about 70 bp of nonspecific DNA downstream of the cognate ICP4 binding site was required for efficient B complex formation. In addition, the C-terminal domain of ICP4 was found to be required for DNA-dependent oligomerization and B complex formation. Gel mobility shift analysis of protein-DNA complexes, combined with supershift analysis using different monoclonal antibodies, indicated that the B complex contained two ICP4 dimers. DNase I footprinting of ICP4-DNA complexes showed that one ICP4 dimer contacts the specific binding site and another ICP4 dimer contacts nonspecific DNA in the B complex. DNA-dependent oligomerization increased the affinity of ICP4 for relatively weak binding sites on large DNA molecules. The results of this study suggest how ICP4 may use multiple weak binding sites to aid in transcription activation.


Asunto(s)
ADN Viral/metabolismo , Proteínas de Unión al ADN/metabolismo , Herpesvirus Humano 1/metabolismo , Proteínas Inmediatas-Precoces/metabolismo , Animales , Sitios de Unión , Chlorocebus aethiops , Huella de ADN , Ensayo de Cambio de Movilidad Electroforética , Unión Proteica , Mapeo de Interacción de Proteínas , Estructura Terciaria de Proteína , Especificidad por Sustrato , Células Vero
8.
Transpl Immunol ; 13(1): 15-24, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15203124

RESUMEN

Pigs are considered a suitable source of cells and organs for xenotransplantation. All known strains of pigs contain porcine endogenous retrovirus (PERV) and PERV released by porcine cells may infect human cells in vitro and severe-combined immunodeficient (SCID) mice in vivo. Humanized SCID (hu-SCID) mice develop immune response to porcine antigens. Here we investigated PERV transmission in humanized SCID-beige mice using porcine peripheral blood mononuclear cells (PBMC) as the donor tissue (and the source of PERV). Mice were infused in the peritoneal cavity with 1.5-3.0 x 10(7) unfractionated human PBMC. Unfractionated porcine PBMC (1.5-3.0 x 10(7) cell/mouse) were infused to the mice simultaneously with human PBMC or 3 weeks after human PBMC infusion. The treated mice were monitored for weight and skin changes, donor cell chimerism, anti-pig antibodies and PERV transmission. All humanized mice tested 5-12 weeks after human PBMC transplantation were macrochimeric (up to 40% of cells in blood) for human cells, where 99% of the human cells were T-lymphocytes. Although human B lymphocytes were very rare in the blood of humanized mice at that point, the mice were positive for human anti-pig natural antibodies. The control SCID-beige mice or mice treated with porcine PBMC alone were negative for anti-porcine antibodies. Approximately 70% of the humanized mice treated with porcine PBMC were also microchimeric for porcine cells. Although some tissue samples of these mice were positive for PERV DNA in the absence of porcine DNA indicating PERV infection, the infection was non-productive as PERV transcripts were not detectable in those tissues. PERV infection of human and mouse cells in vitro by co-culturing with porcine PBMC was also non-productive. Humanized SCID-beige mice suffered weight loss and occasional minor skin changes due to graft vs. host disease caused by human PBMC but none of the mice showed observable effect attributable to the apparent PERV infection alone.


Asunto(s)
Gammaretrovirus , Leucocitos Mononucleares/trasplante , Infecciones por Retroviridae/transmisión , Porcinos/virología , Quimera por Trasplante/inmunología , Quimera por Trasplante/virología , Animales , Humanos , Leucocitos Mononucleares/virología , Ratones , Ratones SCID , ARN Viral/análisis , Infecciones por Retroviridae/inmunología , Porcinos/inmunología , Linfocitos T/inmunología , Linfocitos T/trasplante , Linfocitos T/virología , Quimera por Trasplante/genética , Tolerancia al Trasplante/genética , Tolerancia al Trasplante/inmunología , Trasplante Heterólogo/inmunología
9.
J Immunol Methods ; 285(2): 245-51, 2004 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-14980438

RESUMEN

Although bone marrow transplantation has been used to induce donor-specific tolerance in many allogeneic models, similar effort in xenogeneic transplantation is met with obstacles like more severe graft versus host disease (GVHD). We are currently engaged in developing a GVHD-free hamster-to-rat xenotransplantation model using splenectomy, total body irradiation, and donor bone marrow transplantation. To test donor cell chimerism, particularly in the solid tissues, we developed a semiquantitative polymerase chain reaction (PCR) method using primers specific for hamster beta-actin and mitochondrial cytochrome C oxidase I and II (MCO I and II) genes and rat sex determination region on the Y chromosome (SRY) gene. Using this method, we estimated the level of hamster cells chimerism in rats subjected to splenectomy, total body irradiation (10 Gy), and hamster bone marrow transplantation (3 x 10(8) cell/recipient) and observed high levels of donor cells in all recipient tissues tested.


Asunto(s)
Trasplante de Médula Ósea/inmunología , Reacción en Cadena de la Polimerasa/métodos , Quimera por Trasplante/inmunología , Trasplante Heterólogo/inmunología , Actinas/genética , Animales , Cricetinae , Cartilla de ADN , Complejo IV de Transporte de Electrones/genética , Femenino , Genes sry , Masculino , Ratas , Sensibilidad y Especificidad , Esplenectomía , Irradiación Corporal Total
10.
Genome ; 46(5): 858-69, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14608403

RESUMEN

A major concern in using porcine organs for transplantation is the potential of transmission of porcine endogenous retrovirus (PERV). To investigate the long-term effects of PERV infection on human cells, human embryonic kidney cell line HEK-293 infected with PERV PK-15 was maintained for up to 72 passages and samples were harvested at intervals for use in morphological, growth, and genomic analyses. Morphology, DNA content/cell, and doubling time of uninfected and infected cells were similar. Restriction fragment length polymorphism (RFLP) analysis of PCR-amplified nearly full-length PERV genome showed no alterations in band pattern. RFLP analysis of the long terminal repeats (LTR) showed some changes in band pattern, but not in length. Southern blot analysis of genomic DNA of infected cells indicated random integration of PERV without structural alterations in proviral genome. Semi-quantitative PCR demonstrated a gradual increase of proviral load in the infected cells. Sequence analysis of the LTR region of PERV from infected cells indicated a relatively low rate (6.0 x 10(-4)/bp or about 2 x 10(-6)/bp/generation) of mutation. There were also indications of recombination of PERV strains A and B. Finally, PERV infection had no effect on transcription of human endogenous retrovirus-K (HERV-K) genes. Together, no significant effect attributable to PERV infection was evident on chronically PERV-infected HEK-293 cells.


Asunto(s)
Retrovirus Endógenos/genética , Riñón/citología , Riñón/virología , Porcinos/virología , Animales , Secuencia de Bases , Técnicas de Cultivo de Célula , Línea Celular , Células Clonales , Humanos , Riñón/embriología , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico , Secuencias Repetidas Terminales/genética
11.
Genome ; 45(1): 8-12, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11908671

RESUMEN

Random amplified polymorphic DNA (RAPD) analysis is a valuable tool in studying inter- and intra-specific genetic variations, patterns of gene expression, and for the identification of specific genes using nearly isogenic variants. Here we used RAPD analysis to study the genetic variation in Ginkgo biloba grown in the eastern United States. Our results support the evidence that Southern blot hybridization of RAPD using probes made from cloned DNA fragments allows a more accurate analysis of the RAPD pattern than dye-stained gels or Southern blot hybridization of RAPD blots using probes made from purified PCR products. Using these techniques, we observed a high degree of relatedness among plants grown in certain localities although significant genetic variation may exist in the species, and could be a possible explanation for the observed variations in the efficacy of medications derived from G. biloba extract.


Asunto(s)
Ginkgo biloba/genética , Polimorfismo Genético , District of Columbia , New York , Pennsylvania , Técnica del ADN Polimorfo Amplificado Aleatorio
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