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1.
Nat Med ; 30(4): 1111-1117, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38459181

RESUMEN

Congenital cytomegalovirus (cCMV) is the most common intrauterine infection, leading to neurodevelopmental disabilities. Universal newborn infant screening of cCMV has been increasingly advocated. In the absence of a high-throughput screening test, which can identify all infected newborn infants, the development of an accurate and efficient testing strategy has remained an ongoing challenge. Here we assessed the implementation of pooled saliva polymerase chain reaction (PCR) tests for universal screening of cCMV, in two hospitals of Jerusalem from April 2022 through April 2023. During the 13-month study period, 15,805 infants (93.6% of all live newborn infants) were screened for cCMV using the pooled approach that has since become our routine screening method. The empirical efficiency of the pooling was six (number of tested newborn infants per test), thereby sparing 83% of the saliva tests. Only a minor 3.05 PCR cycle loss of sensitivity was observed for the pooled testing, in accordance with the theoretical prediction for an eight-sample pool. cCMV was identified in 54 newborn infants, with a birth prevalence of 3.4 per 1,000; 55.6% of infants identified with cCMV were asymptomatic at birth and would not have been otherwise targeted for screening. The study demonstrates the wide feasibility and benefits of pooled saliva testing as an efficient, cost-sparing and sensitive approach for universal screening of cCMV.


Asunto(s)
Infecciones por Citomegalovirus , Citomegalovirus , Recién Nacido , Lactante , Humanos , Citomegalovirus/genética , Saliva , Infecciones por Citomegalovirus/diagnóstico , Infecciones por Citomegalovirus/epidemiología , Tamizaje Neonatal/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos
2.
Clin Transplant ; 37(11): e15098, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37563430

RESUMEN

OBJECTIVES: The gastrointestinal (GI) tract is a major human adenovirus (HAdV) replication site in patients undergoing hematopoietic stem cell transplantation (HSCT), yet the prevalence and correlates of HAdV GI infection in this setting have remained poorly recognized, especially among adult HSCT recipients. DESIGN OR METHODS: We retrospectively studied the prevalence and risk factors of HAdV GI-tissue infection in HSCT recipients (73 adults and 15 children) with GI symptoms who underwent GI-tissue biopsy between January-2012 and December-2017. The presence of HAdV in the GI tissues was determined by real-time PCR. RESULTS: HAdV GI-tissue infection was detected in 21 (23.9%) patients, with similar infection rates identified in adults and children. GI-tissue detection was more common at late (>100 days) compared to early times post-transplantation (50% vs. 12.9%, p < .001). The presence of bloody diarrhea, Arab ethnicity (p = .014) and concurrent cytomegalovirus GI-tissue detection (p = .025) were significantly correlated with HAdV GI-tissue infection, while chronic graft versus host disease was of borderline association (p = .055). CONCLUSIONS: Our findings reveal a high rate and new clinical-demographic correlates of HAdV GI-tissue infection in adult and pediatric HSCT recipients with GI symptoms. The findings highlight the need for future prospective studies to assess the relatedness of HAdV infection to the GI symptoms, and the prevalence, impact, and treatment of HAdV GI infection in HSCT recipients.


Asunto(s)
Infecciones por Adenoviridae , Infecciones por Adenovirus Humanos , Adenovirus Humanos , Trasplante de Células Madre Hematopoyéticas , Adulto , Humanos , Niño , Adenoviridae/genética , Estudios Retrospectivos , Estudios Prospectivos , Infecciones por Adenoviridae/diagnóstico , Infecciones por Adenoviridae/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Infecciones por Adenovirus Humanos/diagnóstico , Infecciones por Adenovirus Humanos/epidemiología , Infecciones por Adenovirus Humanos/etiología , Adenovirus Humanos/genética , Biopsia
3.
Microorganisms ; 11(1)2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36677458

RESUMEN

BACKGROUND: previous worldwide reports indicated a substantial short-term reduction in various respiratory infections during the early phase of the SARS-CoV-2 pandemic. AIMS: exploring the long-term impact of the COVID-19 pandemic on respiratory pathogens. METHODS: retrospective analysis of bacterial and viral positivity rate in respiratory samples, between 1 January 2017-30 June 2022 in a tertiary hospital in Jerusalem, Israel. RESULTS: A decline in overall respiratory tests and positivity rate was observed in the first months of the pandemic. Respiratory isolations of Hemophilus influenza and Streptococcus pneumoniae were insignificantly affected and returned to their monthly average by November 2020, despite a parallel surge in COVID-19 activity, while Mycoplasma pneumoniae was almost eliminated from the respiratory pathogens scene. Each viral pathogen acted differently, with adenovirus affected only for few months. Human-metapneumovirus and respiratory-syncytial-virus had reduced activity for approximately a year, and influenza A virus resurged in November 2021 with the elimination of Influenza-B. CONCLUSIONS: After an immediate decline in non-SARS-CoV-2 respiratory infections, each pathogen has a different pattern during a 2-year follow-up. These patterns might be influenced by intrinsic factors of each pathogen and different risk reduction behaviors of the population. Since some of these measures will remain in the following years, we cannot predict the timing of return to pre-COVID-19 normalcy.

4.
PLoS Negl Trop Dis ; 15(10): e0009821, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34662363

RESUMEN

Nodding syndrome (NS) is a catastrophic and enigmatic childhood epilepsy, accompanied by multiple neurological impairments and neuroinflammation. Of all the infectious, environmental and psychological factors associated with NS, the major culprit is Onchocerca Volvulus (Ov)-a parasitic worm transmitted to human by blackflies. NS seems to be an 'Autoimmune Epilepsy' in light of the recent findings of deleterious autoimmune antibodies to Glutamate receptors and to Leiomodin-I in NS patients. Moreover, we recently found immunogenetic fingerprints in HLA peptide-binding grooves associate with protection or susceptibility to NS. Macrophage migration inhibitory factor (MIF) is an immune-regulatory cytokine playing a central role in modulating innate and adaptive immunity. MIF is also involved in various pathologies: infectious, autoimmune and neurodegenerative diseases, epilepsy and others. Herein, two functional polymorphisms in the MIF gene, a -794 CATT5-8 microsatellite repeat and a -173 G/C single-nucleotide polymorphism, were assessed in 49 NS patients and 51 healthy controls from South Sudan. We also measured MIF plasma levels in established NS patients and healthy controls. We discovered that the frequency of the high-expression MIF -173C containing genotype was significantly lower in NS patients compared to healthy controls. Interestingly however, MIF plasma levels were significantly elevated in NS patients than in healthy controls. We further demonstrated that the HLA protective and susceptibility associations are dominant over the MIF association with NS. Our findings suggest that MIF might have a dual role in NS. Genetically controlled high-expression MIF genotype is associated with disease protection. However, elevated MIF in the plasma may contribute to the detrimental autoimmunity, neuroinflammation and epilepsy.


Asunto(s)
Factores Inhibidores de la Migración de Macrófagos/genética , Síndrome del Cabeceo/genética , Adolescente , Adulto , Animales , Niño , Preescolar , Femenino , Genotipo , Humanos , Factores Inhibidores de la Migración de Macrófagos/sangre , Masculino , Repeticiones de Microsatélite , Síndrome del Cabeceo/sangre , Síndrome del Cabeceo/parasitología , Onchocerca volvulus/fisiología , Polimorfismo de Nucleótido Simple , Adulto Joven
5.
Sci Transl Med ; 13(589)2021 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-33619081

RESUMEN

Pooling multiple swab samples before RNA extraction and real-time reverse transcription polymerase chain reaction (RT-PCR) analysis has been proposed as a strategy to reduce costs and increase throughput of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) tests. However, reports on practical large-scale group testing for SARS-CoV-2 have been scant. Key open questions concern reduced sensitivity due to sample dilution, the rate of false positives, the actual efficiency (number of tests saved by pooling), and the impact of infection rate in the population on assay performance. Here, we report an analysis of 133,816 samples collected between April and September 2020 and tested by Dorfman pooling for the presence of SARS-CoV-2. We spared 76% of RNA extraction and RT-PCR tests, despite the frequently changing prevalence (0.5 to 6%). We observed pooling efficiency and sensitivity that exceeded theoretical predictions, which resulted from the nonrandom distribution of positive samples in pools. Overall, our findings support the use of pooling for efficient large-scale SARS-CoV-2 testing.


Asunto(s)
COVID-19 , SARS-CoV-2 , Prueba de COVID-19 , Humanos , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad , Manejo de Especímenes
6.
Cancers (Basel) ; 13(3)2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33499244

RESUMEN

The H19-derived microRNA-675 (miR-675) has been implicated as both tumor promoter and tumor suppressor and also plays a role in liver inflammation. We found that miR-675 promotes cell death in human hepatocellular carcinoma (HCC) cell lines. We show that Fas-associated protein with death domain (FADD), a mediator of apoptotic cell death signaling, is downregulated by miR-675 and a negative correlation exists between miR-675 and FADD expression in mouse models of HCC (p = 0.014) as well as in human samples (p = 0.017). We demonstrate in a mouse model of liver inflammation that overexpression of miR-675 promotes necroptosis, which can be inhibited by the necroptosis-specific inhibitor Nec-1/Nec-1s. miR-675 induces the level of both p-MLKL (Mixed Lineage Kinase Domain-Like Pseudokinase) and RIP3 (receptor-interacting protein 3), which are key signaling molecules in necroptosis, and enhances MLKL binding to RIP3. miR-675 also inhibits the levels of cleaved caspases 8 and 3, suggesting that miR-675 induces a shift from apoptosis to a necroptotic cellular pathway. In conclusion, downregulation of FADD by miR-675 promotes liver necroptosis in response to inflammatory signals. We propose that this regulation cascade can stimulate and enhance the inflammatory response in the liver, making miR-675 an important regulator in liver inflammation and potentially also in HCC.

8.
PLoS Negl Trop Dis ; 14(7): e0008436, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32639997

RESUMEN

Nodding syndrome (NS) is a devastating and enigmatic childhood epilepsy. NS is accompanied by multiple neurological impairments and neuroinflammation, and associated with the parasite Onchocerca volvulus (Ov) and other environmental factors. Moreover, NS seems to be an 'Autoimmune Epilepsy' since: 1. ~50% of NS patients have neurotoxic cross-reactive Ov/Leimodin-I autoimmune antibodies. 2. Our recently published findings: Most (~86%) of NS patients have glutamate-receptor AMPA-GluR3B peptide autoimmune antibodies that bind, induce Reactive Oxygen Species, and kill both neural cells and T cells. Furthermore, NS patient's IgG induce seizures, brain multiple damage alike occurring in brains of NS patients, and elevation of T cells and activated microglia and astrocytes, in brains of normal mice. Human Leukocyte antigen (HLA) class I and II molecules are critical for initiating effective beneficial immunity against foreign microorganisms and contributing to proper brain function, but also predispose to detrimental autoimmunity against self-peptides. We analyzed seven HLA loci, either by next-generation-sequencing or Sequence-Specific-Oligonucleotide-Probe, in 48 NS patients and 51 healthy controls from South Sudan. We discovered that NS associates significantly with both protective HLA haplotype: HLA-B*42:01, C*17:01, DRB1*03:02, DQB1*04:02 and DQA1*04:01, and susceptible motif: Ala24, Glu63 and Phe67, in the HLA-B peptide-binding groove. These amino acids create a hydrophobic and sterically closed peptide-binding HLA pocket, favoring proline residue. Our findings suggest that immunogenetic fingerprints in HLA peptide-binding grooves tentatively associate with protection or susceptibility to NS. Accordingly, different HLA molecules may explain why under similar environmental factors, only some children, within the same families, tribes and districts, develop NS, while others do not.


Asunto(s)
Antígenos HLA/química , Antígenos HLA/inmunología , Síndrome del Cabeceo/inmunología , Adolescente , Adulto , Secuencias de Aminoácidos , Autoanticuerpos/inmunología , Estudios de Casos y Controles , Niño , Preescolar , Susceptibilidad a Enfermedades , Femenino , Antígenos HLA/genética , Humanos , Masculino , Síndrome del Cabeceo/genética , Síndrome del Cabeceo/prevención & control , Receptores AMPA/genética , Receptores AMPA/inmunología , Sudán del Sur , Adulto Joven
10.
PLoS One ; 14(1): e0210173, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30645600

RESUMEN

BACKGROUND & AIMS: Acute hepatitis C (AHC) is not frequently identified because patients are usually asymptomatic, although may be recognized after iatrogenic exposures such as needle stick injuries, medical injection, and acupuncture. We describe an outbreak of AHC among 12 patients who received IV saline flush from a single multi-dose vial after intravenous contrast administration for a computerized tomography (CT) scan. The last patient to receive IV contrast with saline flush from a multi-dose vial at the clinic on the previous day was known to have chronic HCV genotype 1b (termed potential source, PS). Here we sought to confirm (via genetic analysis) the source of infection and to predict the minimal contaminating level of IV saline flush needed to transmit infectious virus to all patients. METHODS: In order to confirm the source of infection, we sequenced the HCV E1E2 region in 7 CT patients, in PS, and in 2 control samples from unrelated patients also infected with HCV genotype 1b. A transmission probabilistic model was developed to predict the contamination volume of blood that would have been sufficient to transmit infectious virus to all patients. RESULTS: Viral sequencing showed close clustering of the cases with the PS. The transmission probabilistic model predicted that contamination of the multi-dose saline vial with 0.6-8.7 microliters of blood would have been sufficient to transmit infectious virus to all patients. CONCLUSION: Analysis of this unique cohort provides a new understanding of HCV transmission with respect to contaminating volumes and viral titers.


Asunto(s)
Infección Hospitalaria/transmisión , Brotes de Enfermedades , Contaminación de Medicamentos , Hepatitis C/transmisión , Administración Intravenosa , Adolescente , Adulto , Anciano , Medios de Contraste/administración & dosificación , Infección Hospitalaria/sangre , Infección Hospitalaria/epidemiología , Infección Hospitalaria/virología , Femenino , Genotipo , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C/sangre , Hepatitis C/epidemiología , Hepatitis C/virología , Humanos , Masculino , Modelos Estadísticos , Agujas , ARN Viral/aislamiento & purificación , Solución Salina/administración & dosificación , Tomografía Computarizada por Rayos X , Proteínas del Envoltorio Viral/genética , Carga Viral
11.
Gastroenterology ; 153(5): 1404-1415, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28802563

RESUMEN

BACKGROUND & AIMS: Effective treatments are needed for hepatic steatosis characterized by accumulation of triglycerides in hepatocytes, which leads to hepatocellular carcinoma. MicroRNA 122 (MIR122) is expressed only in the liver, where it regulates lipid metabolism. We investigated the mechanism by which free fatty acids (FFAs) regulate MIR122 expression and the effect of MIR122 on triglyceride synthesis. METHODS: We analyzed MIR122 promoter activity and validated its target mRNAs by transfection of Luciferase reporter plasmids into Huh7, BNL-1ME, and HEK293 cultured cell lines. We measured levels of microRNAs and mRNAs by quantitative real-time PCR analysis of RNA extracted from plasma, liver, muscle, and adipose tissues of C57BL/6 mice given the FFA-inducer CL316243. MIR122 was inhibited using an inhibitor of MIR122. Metabolic profiles of mice were determined using metabolic chambers and by histologic analyses of liver tissues. We performed RNA sequence analyses to identify metabolic pathways involving MIR122. RESULTS: We validated human Agpat1 and Dgat1 mRNAs, involved in triglyceride synthesis, as targets of MIR122. FFAs increased MIR122 expression in livers of mice by activating the retinoic acid-related orphan receptor alpha, and induced secretion of MIR122 from liver to blood. Circulating MIR122 entered muscle and adipose tissues of mice, reducing mRNA levels of genes involved in triglyceride synthesis. Mice injected with an inhibitor of MIR122 and then given CL316243, accumulated triglycerides in liver and muscle tissues, and had reduced rates of ß-oxidation. There was a positive correlation between level of FFAs and level of MIR122 in plasma samples from 6 healthy individuals, collected before and during fasting. CONCLUSIONS: In biochemical and histologic studies of plasma, liver, muscle, and adipose tissues from mice, we found that FFAs increase hepatic expression and secretion of MIR122, which regulates energy storage vs expenditure in liver and peripheral tissues. Strategies to reduce triglyceride levels, by increasing MIR122, might be developed for treatment of metabolic syndrome.


Asunto(s)
Metabolismo Energético , Ácidos Grasos no Esterificados/metabolismo , Hígado/metabolismo , MicroARNs/metabolismo , Músculo Esquelético/metabolismo , Triglicéridos/biosíntesis , 1-Acilglicerol-3-Fosfato O-Aciltransferasa/genética , 1-Acilglicerol-3-Fosfato O-Aciltransferasa/metabolismo , Tejido Adiposo/metabolismo , Animales , Antagomirs/genética , Antagomirs/metabolismo , Diacilglicerol O-Acetiltransferasa/genética , Diacilglicerol O-Acetiltransferasa/metabolismo , Dioxoles/farmacología , Metabolismo Energético/efectos de los fármacos , Células HEK293 , Humanos , Hígado/efectos de los fármacos , Masculino , Metabolómica/métodos , Ratones Endogámicos C57BL , MicroARNs/genética , Músculo Esquelético/efectos de los fármacos , Oxidación-Reducción , Regiones Promotoras Genéticas , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Tiempo , Transfección
12.
Gastroenterology ; 151(5): 999-1010.e3, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27477940

RESUMEN

BACKGROUND & AIMS: Anemia is associated commonly with acute and chronic inflammation, but the mechanisms of their interaction are not clear. We investigated whether microRNA 122 (MIR122), which is generated in the liver and is secreted into the blood, is involved in the development of anemia associated with inflammation. METHODS: We characterized the primary transcript of the human liver-specific MIR122 using Northern blot, quantitative real-time polymerase chain reaction, and 3' and 5' rapid amplification of cDNA ends analyses. We studied regulation of MIR122 in human hepatocellular carcinoma cell lines (Huh7 and HepG2) as well as in C57BL/6 and mice with disruption of the tumor necrosis factor (Tnf) gene. Liver tissues were collected and analyzed by bioluminescence imaging or immunofluorescence. Inflammation in mice was induced by lipopolysaccharide (LPS) or by cerulein injections. Mice were given 4 successive injections of LPS, leading to inflammation-induced anemia. Steatohepatitis was induced with a choline-deficient, high-fat diet. Hemolytic anemia was stimulated by phenylhydrazine injection. MIR122 was inhibited in mice by tail-vein injection of an oligonucleotide antagonist of MIR122. MicroRNA and messenger RNA levels were determined by quantitative real-time polymerase chain reaction. RESULTS: The primary transcript of MIR122 spanned 5 kb, comprising 3 exons; the third encodes MIR122. Within the MIR122 promoter region we identified a nuclear factor-κB binding site and showed that RELA (NF-κB p65 subunit), as well as activators of NF-κB (TNF and LPS), increased promoter activity of MIR122. Administration of LPS to mice induced secretion of MIR122 into blood, which required TNF. Secreted MIR122 reached the kidney and reduced expression of erythropoietin (Epo), which we identified as a MIR122 target gene. Injection of mice with an oligonucleotide antagonist of MIR122 increased blood levels of EPO, reticulocytes, and hemoglobin. We found an inverse relationship between blood levels of MIR122 and EPO in mice with acute pancreatitis or steatohepatitis, and also in patients with acute inflammation. CONCLUSION: In mice, we found that LPS-induced inflammation increases blood levels of MIR122, which reduces expression of Epo in the kidney; this is a mechanism of inflammation-induced anemia. Strategies to block MIR122 in patients with inflammation could reduce the development or progression of anemia.


Asunto(s)
Anemia/etiología , Eritropoyetina/sangre , Inflamación/complicaciones , MicroARNs/metabolismo , Anemia/metabolismo , Animales , Biomarcadores/metabolismo , Northern Blotting , Femenino , Células Hep G2 , Humanos , Inflamación/metabolismo , Riñón/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/antagonistas & inhibidores , Reacción en Cadena en Tiempo Real de la Polimerasa
13.
Hepatology ; 64(5): 1623-1636, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27302319

RESUMEN

The tumor suppressor p53 is a central regulator of signaling pathways that controls the cell cycle and maintains the integrity of the human genome. p53 level is regulated by mouse double minute 2 homolog (Mdm2), which marks p53 for proteasomal degradation. The p53-Mdm2 circuitry is subjected to complex regulation by a variety of mechanisms, including microRNAs (miRNAs). We found a novel effector of this regulatory circuit, namely, miR-122*, the passenger strand of the abundantly expressed liver-specific miR-122. Here, we demonstrate that miR-122* levels are reduced in human hepatocellular carcinoma (HCC). We found that miR-122* targets Mdm2, thus participating as an important player in the p53-Mdm2 circuitry. Moreover, we observed significant negative correlation between levels of miR-122* and Mdm2 in a large set of human HCC samples. In vivo tumorigenicity assays demonstrate that miR-122* is capable of inhibiting tumor growth, emphasizing the tumor-suppressor characteristics of this miRNA. Furthermore, we show that blocking miR-122 in murine livers with an antagomiR-122 (miRNA inhibitor) results in miR-122* accumulation, leading to Mdm2 repression followed by elevated p53 protein levels. CONCLUSION: miR-122*, the passenger strand of miR-122, regulates the activity of p53 by targeting Mdm2. Importantly, similarly to miR-122, miR-122* is significantly down-regulated in human HCC. We therefore propose that miR-122* is an important contributor to the tumor suppression activity previously attributed solely to miR-122. (Hepatology 2016;64:1623-1636).


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , MicroARNs/fisiología , Proteínas Proto-Oncogénicas c-mdm2/fisiología , Proteína p53 Supresora de Tumor/fisiología , Animales , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Supresoras de Tumor/fisiología
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