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1.
Nat Immunol ; 23(8): 1273-1283, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35835962

RESUMEN

Type I interferons (IFN-Is) are central regulators of anti-tumor immunity and responses to immunotherapy, but they also drive the feedback inhibition underlying therapeutic resistance. In the present study, we developed a mass cytometry approach to quantify IFN-I-stimulated protein expression across immune cells and used multi-omics to uncover pre-therapy cellular states encoding responsiveness to inflammation. Analyzing peripheral blood cells from multiple cancer types revealed that differential responsiveness to IFN-Is before anti-programmed cell death protein 1 (PD1) treatment was highly predictive of long-term survival after therapy. Unexpectedly, IFN-I hyporesponsiveness efficiently predicted long-term survival, whereas high responsiveness to IFN-I was strongly associated with treatment failure and diminished survival time. Peripheral IFN-I responsive states were not associated with tumor inflammation, identifying a disconnect between systemic immune potential and 'cold' or 'hot' tumor states. Mechanistically, IFN-I responsiveness was epigenetically imprinted before therapy, poising cells for differential inflammatory responses and dysfunctional T cell effector programs. Thus, we identify physiological cell states with clinical importance that can predict success and long-term survival of PD1-blocking immunotherapy.


Asunto(s)
Interferón Tipo I , Humanos , Inmunoterapia , Inflamación , Linfocitos T
2.
Immunity ; 55(5): 847-861.e10, 2022 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-35545033

RESUMEN

The microbiota are vital for immune homeostasis and provide a competitive barrier to bacterial and fungal pathogens. Here, we investigated how gut commensals modulate systemic immunity and response to viral infection. Antibiotic suppression of the gut microbiota reduced systemic tonic type I interferon (IFN-I) and antiviral priming. The microbiota-driven tonic IFN-I-response was dependent on cGAS-STING but not on TLR signaling or direct host-bacteria interactions. Instead, membrane vesicles (MVs) from extracellular bacteria activated the cGAS-STING-IFN-I axis by delivering bacterial DNA into distal host cells. DNA-containing MVs from the gut microbiota were found in circulation and promoted the clearance of both DNA (herpes simplex virus type 1) and RNA (vesicular stomatitis virus) viruses in a cGAS-dependent manner. In summary, this study establishes an important role for the microbiota in peripheral cGAS-STING activation, which promotes host resistance to systemic viral infections. Moreover, it uncovers an underappreciated risk of antibiotic use during viral infections.


Asunto(s)
Microbioma Gastrointestinal , Herpesvirus Humano 1 , Interferón Tipo I , Virosis , Antibacterianos , Antivirales , Humanos , Inmunidad Innata , Proteínas de la Membrana/genética , Nucleotidiltransferasas/genética
3.
Plant Cell ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842334

RESUMEN

Plasmodesmata connect adjoining plant cells, allowing molecules to move between the connected cells for communication and sharing resources. It has been well established that the plant polysaccharide callose is deposited at plasmodesmata, regulating their aperture and function. Among proteins involved in maintaining callose homeostasis, PLASMODESMATA-LOCATED PROTEINSs (PDLPs) promote callose deposition at plasmodesmata. This study explored the function of PDLP5 and PDLP6 in different cell types. We discovered that PDLP5 and PDLP6 are expressed in non-overlapping cell types in Arabidopsis (Arabidopsis thaliana). The overexpression of PDLP5 and PDLP6 results in the overaccumulation of plasmodesmal callose at different cell interfaces, indicating that PDLP5 and PDLP6 are active in different cell types. We also observed two distinct patterns of starch accumulation in mature leaves of PDLP5 and PDLP6 overexpressors. An enzyme-catalyzed proximity labeling approach was used to identify putative functional partners of the PDLPs. We identified SUCROSE SYNTHASE6 (SUS6) as a functional partner of PDLP6 in the vasculature. We further demonstrated that PDLP6 physically and genetically interacts with SUS6. In addition, CALLOSE SYNTHASE7 (CALS7) physically interacts with SUS6 and PDLP6. Genetic interaction studies showed that CALS7 is required for PDLP6 function. We propose that PDLP6 functions with SUS6 and CALS7 in the vasculature to regulate plasmodesmal function.

4.
Proc Natl Acad Sci U S A ; 121(24): e2320898121, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38833464

RESUMEN

The World Health Organization identifies a strong surveillance system for malaria and its mosquito vector as an essential pillar of the malaria elimination agenda. Anopheles salivary antibodies are emerging biomarkers of exposure to mosquito bites that potentially overcome sensitivity and logistical constraints of traditional entomological surveys. Using samples collected by a village health volunteer network in 104 villages in Southeast Myanmar during routine surveillance, the present study employs a Bayesian geostatistical modeling framework, incorporating climatic and environmental variables together with Anopheles salivary antigen serology, to generate spatially continuous predictive maps of Anopheles biting exposure. Our maps quantify fine-scale spatial and temporal heterogeneity in Anopheles salivary antibody seroprevalence (ranging from 9 to 99%) that serves as a proxy of exposure to Anopheles bites and advances current static maps of only Anopheles occurrence. We also developed an innovative framework to perform surveillance of malaria transmission. By incorporating antibodies against the vector and the transmissible form of malaria (sporozoite) in a joint Bayesian geostatistical model, we predict several foci of ongoing transmission. In our study, we demonstrate that antibodies specific for Anopheles salivary and sporozoite antigens are a logistically feasible metric with which to quantify and characterize heterogeneity in exposure to vector bites and malaria transmission. These approaches could readily be scaled up into existing village health volunteer surveillance networks to identify foci of residual malaria transmission, which could be targeted with supplementary interventions to accelerate progress toward elimination.


Asunto(s)
Anopheles , Teorema de Bayes , Malaria , Mosquitos Vectores , Animales , Anopheles/parasitología , Mosquitos Vectores/parasitología , Humanos , Malaria/transmisión , Malaria/epidemiología , Malaria/inmunología , Malaria/parasitología , Estudios Seroepidemiológicos , Mordeduras y Picaduras de Insectos/epidemiología , Mordeduras y Picaduras de Insectos/inmunología , Mordeduras y Picaduras de Insectos/parasitología , Esporozoítos/inmunología
5.
Environ Res ; 252(Pt 1): 118839, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38570131

RESUMEN

Weeds pose multifaceted challenges in rice cultivation, leading to substantial economic losses through reduced yield and poor grain quality. Harnessing the natural genetic diversity in germplasm collections becomes crucial for identifying novel herbicide resistance loci in crops. A comprehensive analysis was conducted on 475 rice accessions from the KRICE depository, assessing their response to TFT (tefuryltrione) and probing the underlying HIS1 (HPPD INHIBITOR SENSITIVE 1) genotypic variations. The HIS1 gene, responsible for detoxifying benzobicyclon (BBC) and imparting broad-spectrum herbicide resistance, holds significant promise in rice breeding. This study explores the genetic landscape of HIS1 within Korean rice collection (KRICE), aiming to unveil genetic variations, haplotype diversity, and evolutionary relationships across diverse rice ecotypes. The indica ecotype showed the highest nucleotide diversity, while the wild and temperate japonica groups exhibited low diversity, hinting at selective sweeps and possible population expansion. Negative Tajima's D values in temperate japonica and wild groups indicate an excess of low-frequency mutations, potentially resulting from selective sweeps. In contrast, with positive Tajima's D values, admixture, indica, and aus groups suggest balancing selection. Furthermore, haplotype analysis uncovered 42 distinct haplotypes within KRICE, with four shared haplotypes between cultivated and wild accessions, four specific to cultivated accessions, and 34 specific to wild types. Phenotypic assessments of these haplotypes revealed that three haplotypes, viz., Hap_1 (predominant in japonica), Hap_2 (predominant in indica), and Hap_3 (specific to indica), displayed significant differences from aus-specific Hap_4 and indica-specific Hap_5. This study offers insights into genetic diversity, selective pressures, and ecotype-specific responses, ultimately paving the way for developing HPPD-inhibiting herbicide-resistant rice cultivars.


Asunto(s)
Variación Genética , Haplotipos , Herbicidas , Oryza , Oryza/genética , Resistencia a los Herbicidas/genética , Evolución Molecular
6.
J Cell Sci ; 134(5)2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33106317

RESUMEN

Autophagy plays an essential role in the defense against many microbial pathogens as a regulator of both innate and adaptive immunity. Some pathogens have evolved sophisticated mechanisms that promote their ability to evade or subvert host autophagy. Here, we describe a novel mechanism of autophagy modulation mediated by the recently discovered Vibrio cholerae cytotoxin, motility-associated killing factor A (MakA). pH-dependent endocytosis of MakA by host cells resulted in the formation of a cholesterol-rich endolysosomal membrane aggregate in the perinuclear region. Aggregate formation induced the noncanonical autophagy pathway driving unconventional LC3 (herein referring to MAP1LC3B) lipidation on endolysosomal membranes. Subsequent sequestration of the ATG12-ATG5-ATG16L1 E3-like enzyme complex, required for LC3 lipidation at the membranous aggregate, resulted in an inhibition of both canonical autophagy and autophagy-related processes, including the unconventional secretion of interleukin-1ß (IL-1ß). These findings identify a novel mechanism of host autophagy modulation and immune modulation employed by V. cholerae during bacterial infection.


Asunto(s)
Proteínas Asociadas a Microtúbulos , Vibrio cholerae , Autofagia , Proteínas Relacionadas con la Autofagia/genética , Citotoxinas , Vitamina B 12/análogos & derivados
7.
Plant Cell ; 32(3): 595-611, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31888968

RESUMEN

A hallmark of multicellular organisms is their ability to maintain physiological homeostasis by communicating among cells, tissues, and organs. In plants, intercellular communication is largely dependent on plasmodesmata (PD), which are membrane-lined channels connecting adjacent plant cells. Upon immune stimulation, plants close PD as part of their immune responses. Here, we show that the bacterial pathogen Pseudomonas syringae deploys an effector protein, HopO1-1, that modulates PD function. HopO1-1 is required for P. syringae to spread locally to neighboring tissues during infection. Expression of HopO1-1 in Arabidopsis (Arabidopsis thaliana) increases the distance of PD-dependent molecular flux between neighboring plant cells. Being a putative ribosyltransferase, the catalytic activity of HopO1-1 is required for regulation of PD. HopO1-1 physically interacts with and destabilizes the plant PD-located protein PDLP7 and possibly PDLP5. Both PDLPs are involved in bacterial immunity. Our findings reveal that a pathogenic bacterium utilizes an effector to manipulate PD-mediated host intercellular communication for maximizing the spread of bacterial infection.


Asunto(s)
Arabidopsis/microbiología , Plasmodesmos/microbiología , Pseudomonas syringae/crecimiento & desarrollo , Pseudomonas syringae/patogenicidad , Adenosina Difosfato Ribosa/metabolismo , Arabidopsis/inmunología , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Proteínas Bacterianas/metabolismo , Membrana Celular/metabolismo , Inmunidad de la Planta , Unión Proteica , Dominios Proteicos , Estabilidad Proteica , Transporte de Proteínas , Pseudomonas syringae/inmunología , Virulencia
8.
Cell Mol Life Sci ; 79(10): 518, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36104457

RESUMEN

In our search for innovative drugs that could improve periodontal treatment outcomes, autophagy and its anomalies represent a potential target for therapeutic intervention. We sought to identify autophagy defects in murine experimental periodontitis and study the effectiveness of P140, a phosphopeptide known to bind HSPA8 and inhibit its chaperone properties, and that corrects autophagy dysfunctions in several autoimmune and inflammatory diseases. Experimental periodontitis was induced by placing silk ligature around mandibular first molars. Sick mice were treated intraperitoneally with either P140 or a control, scrambled peptide. After 10 days, mandibles were harvested and bone loss was measured by micro-CT. Immune cells infiltration was studied by histological analyses. Cytokines levels and autophagy-related markers expression were evaluated by qRT-PCR and western blotting. A comparison with non-affected mice revealed significant alterations in the autophagy processes in mandibles of diseased mice, especially in the expression of sequestosome 1/p62, Maplc3b, Atg5, Ulk1, and Lamp2. In vivo, we showed that P140 normalized the dysregulated expression of several autophagy-related genes. In addition, it diminished the infiltration of activated lymphocytes and pro-inflammatory cytokines. Unexpectedly P140 decreased the extent of bone loss affecting the furcation and alveolar areas. Our results indicate that P140, which was safe in clinical trials including hundreds of autoimmune patients with systemic lupus erythematosus, not only decreases the inflammatory effects observed in mandibular tissues of ligation-induced mice but strikingly also contributes to bone preservation. Therefore, the therapeutic peptide P140 could be repositioned as a decisive breakthrough for the future therapeutic management of periodontitis.


Asunto(s)
Fragmentos de Péptidos , Periodontitis , Animales , Citocinas/genética , Modelos Animales de Enfermedad , Ratones , Fragmentos de Péptidos/farmacología , Periodontitis/tratamiento farmacológico , Fosfopéptidos
9.
Cancer Metastasis Rev ; 40(1): 7-30, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32929562

RESUMEN

Recent developments in pre-clinical screening tools, that more reliably predict the clinical effects and adverse events of candidate therapeutic agents, has ushered in a new era of drug development and screening. However, given the rapid pace with which these models have emerged, the individual merits of these translational research tools warrant careful evaluation in order to furnish clinical researchers with appropriate information to conduct pre-clinical screening in an accelerated and rational manner. This review assesses the predictive utility of both well-established and emerging pre-clinical methods in terms of their suitability as a screening platform for treatment response, ability to represent pharmacodynamic and pharmacokinetic drug properties, and lastly debates the translational limitations and benefits of these models. To this end, we will describe the current literature on cell culture, organoids, in vivo mouse models, and in silico computational approaches. Particular focus will be devoted to discussing gaps and unmet needs in the literature as well as current advancements and innovations achieved in the field, such as co-clinical trials and future avenues for refinement.


Asunto(s)
Neoplasias , Investigación Biomédica Traslacional , Animales , Técnicas de Cultivo de Célula , Humanos , Ratones , Neoplasias/tratamiento farmacológico , Organoides , Proteómica
10.
BMC Infect Dis ; 22(1): 653, 2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35902825

RESUMEN

BACKGROUND: While national malaria incidence has been declining in Myanmar, some subregions within the nation continue to have high burdens of malaria morbidity and mortality. This study assessed the malaria situation in one of these regions, Banmauk Township, located near the Myanmar-India border. Our goal was to provide a detailed description of the malaria epidemiology in this township and to provide some evidence-based recommendations to formulate a strategy for reaching the national malaria elimination plan. Banmauk consistently has one of the highest malaria burdens in Myanmar. METHODS: With the implementation of strengthened malaria control and surveillance activities after the endorsement of a national malaria elimination plan in 2015, detailed incidence data were obtained for 2016-2018 for Banmauk Township. The data include patient demographics, parasite species, disease severity, and disease outcome. Data were analyzed to identify characteristics, trends, distribution, and risk factors. RESULTS: During 2016-2018, 2,402 malaria cases were reported, with Plasmodium falciparum accounting for 83.4% of infections. Both P. falciparum and P. vivax were transmitted more frequently during the rainy season (May-October). Despite intensified control, the annual parasite incidence rate (API) in 2017 (11.0) almost doubled that in 2016 (6.5). In total, 2.5% (59/2042) of the cases, of which 54 P. falciparum and 5 P. vivax, were complicated cases, resulting in 5 deaths. Malaria morbidity was high in children < 15 years and accounted for 33.4% of all cases and about 47% of the complicated cases. Older age groups and males living with poor transportation conditions were more likely to test positive especially in rainy and cold seasons. Despite the clear seasonality of malaria, severe cases were found among young children even more common in the dry season, when malaria incidence was low. CONCLUSIONS: Despite the declining trend, the malaria burden remained high in Banmauk Township. Our study also documented severe cases and deaths from both falciparum and vivax malaria. P. falciparum remained the predominant parasite species, demanding increased efforts to achieve the goal of elimination of P. falciparum by 2025. As P. falciparum cases decreased, the proportion of cases attributable to P. vivax increased. In order to eliminate malaria, it will likely be important to increasingly target this species as well.


Asunto(s)
Malaria Falciparum , Malaria Vivax , Malaria , Anciano , Niño , Preescolar , Humanos , Malaria/epidemiología , Malaria/parasitología , Malaria/prevención & control , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Malaria Falciparum/prevención & control , Malaria Vivax/epidemiología , Malaria Vivax/parasitología , Malaria Vivax/prevención & control , Masculino , Mianmar/epidemiología , Plasmodium falciparum , Plasmodium vivax , Factores de Riesgo
11.
Nature ; 539(7630): 524-529, 2016 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-27882964

RESUMEN

High humidity has a strong influence on the development of numerous diseases affecting the above-ground parts of plants (the phyllosphere) in crop fields and natural ecosystems, but the molecular basis of this humidity effect is not understood. Previous studies have emphasized immune suppression as a key step in bacterial pathogenesis. Here we show that humidity-dependent, pathogen-driven establishment of an aqueous intercellular space (apoplast) is another important step in bacterial infection of the phyllosphere. Bacterial effectors, such as Pseudomonas syringae HopM1, induce establishment of the aqueous apoplast and are sufficient to transform non-pathogenic P. syringae strains into virulent pathogens in immunodeficient Arabidopsis thaliana under high humidity. Arabidopsis quadruple mutants simultaneously defective in a host target (AtMIN7) of HopM1 and in pattern-triggered immunity could not only be used to reconstitute the basic features of bacterial infection, but also exhibited humidity-dependent dyshomeostasis of the endophytic commensal bacterial community in the phyllosphere. These results highlight a new conceptual framework for understanding diverse phyllosphere-bacterial interactions.


Asunto(s)
Arabidopsis/microbiología , Interacciones Huésped-Patógeno , Humedad , Enfermedades de las Plantas/microbiología , Hojas de la Planta/microbiología , Pseudomonas syringae/patogenicidad , Agua/metabolismo , Arabidopsis/inmunología , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas Bacterianas/metabolismo , Factores de Intercambio de Guanina Nucleótido , Homeostasis , Tolerancia Inmunológica , Enfermedades de las Plantas/inmunología , Inmunidad de la Planta , Hojas de la Planta/inmunología , Pseudomonas syringae/genética , Pseudomonas syringae/inmunología , Pseudomonas syringae/metabolismo , Simbiosis , Virulencia/inmunología
12.
Support Care Cancer ; 30(10): 8511-8517, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35579754

RESUMEN

Thrombosis is the second leading cause of death in cancer patients. Patients with pancreatic cancer (PC) have a very high risk of developing venous thromboembolism (VTE). Even though primary ambulatory thromboprophylaxis (PATP) could decrease this risk, there are uncertain issues with regard to the choice and dose of anticoagulants, duration of anticoagulant therapy, and patient selection criteria. In addition, the current practice guidelines on PATP in PC patients are equivocal. This review critically appraises the evidence on the use of PATP in PC patients receiving chemotherapy.


Asunto(s)
Neoplasias , Neoplasias Pancreáticas , Trombosis , Tromboembolia Venosa , Anticoagulantes , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/tratamiento farmacológico , Trombosis/tratamiento farmacológico , Tromboembolia Venosa/tratamiento farmacológico , Tromboembolia Venosa/etiología , Tromboembolia Venosa/prevención & control , Neoplasias Pancreáticas
13.
Int J Cancer ; 149(2): 442-459, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-33720402

RESUMEN

Colorectal cancer is one of the leading causes of cancer-related death worldwide. The adenomatous polyposis coli (APC) gene is mutated in hereditary colorectal tumors and in more than 80% of sporadic colorectal tumors. APC mutations impair ß-catenin degradation, leading to its permanent stabilization and increased transcription of cancer-driving target genes. In colon cancer, impairment of ß-catenin degradation leads to its cytoplasmic accumulation, nuclear translocation, and subsequent activation of tumor cell proliferation. Suppressing ß-catenin signaling in cancer cells therefore appears to be a promising strategy for new anticancer strategies. Recently, we discovered a novel Vibrio cholerae cytotoxin, motility-associated killing factor A (MakA), that affects both invertebrate and vertebrate hosts. It promotes bacterial survival and proliferation in invertebrate predators but has unknown biological role(s) in mammalian hosts. Here, we report that MakA can cause lethality of tumor cells via induction of apoptosis. Interestingly, MakA exhibited potent cytotoxic activity, in particular against several tested cancer cell lines, while appearing less toxic toward nontransformed cells. MakA bound to the tumor cell surface became internalized into the endolysosomal compartment and induced leakage of endolysosomal membranes, causing cytosolic release of cathepsins and activation of proapoptotic proteins. In addition, MakA altered ß-catenin integrity in colon cancer cells, partly through a caspase- and proteasome-dependent mechanism. Importantly, MakA inhibited ß-catenin-mediated tumor cell proliferation. Remarkably, intratumor injection of MakA significantly reduced tumor development in a colon cancer murine solid tumor model. These data identify MakA as a novel candidate to be considered in new strategies for development of therapeutic agents against colon cancer.


Asunto(s)
Neoplasias del Colon/tratamiento farmacológico , Citotoxinas/administración & dosificación , Vibrio cholerae/metabolismo , Vía de Señalización Wnt/efectos de los fármacos , beta Catenina/metabolismo , Animales , Proteínas Bacterianas/administración & dosificación , Proteínas Bacterianas/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Citotoxinas/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HCT116 , Humanos , Ratones , Ensayos Antitumor por Modelo de Xenoinjerto
14.
BMC Med ; 19(1): 121, 2021 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-34044836

RESUMEN

BACKGROUND: In the Greater Mekong Subregion (GMS), current malaria surveillance strategies rely on a network of village health volunteers (VHVs) reporting the results of rapid diagnostic tests (RDTs), known to miss many asymptomatic infections. Integration of more sensitive diagnostic molecular and serological measures into the VHV network may improve surveillance of residual malaria transmission in hard-to-reach areas in the region and inform targeted interventions and elimination responses. However, data on residual malaria transmission that would be captured by these measures in the VHV-led testing and treatment surveillance network in the GMS is unknown. METHODS: A total of 114 VHVs were trained to collect dried blood spots from villagers undergoing routine RDTs as part of VHV-led active and passive case detection from April 2015 to June 2016. Samples were subjected to molecular testing (quantitative polymerase chain reaction [qPCR]) to determine Plasmodium falciparum and P. vivax infection and serological testing (against P. falciparum and P. vivax antigens) to determine exposure to P. falciparum and P. vivax. RESULTS: Over 15 months, 114 VHVs performed 32,194 RDTs and collected samples for molecular (n = 13,157) and serological (n = 14,128) testing. The prevalence of molecular-detectable P. falciparum and P. vivax infection was 3.2% compared to the 0.16% prevalence of Plasmodium spp. by RDT, highlighting the large burden of infections undetected by standard surveillance. Peaks in anti-P. falciparum, but not P. vivax, merozoite IgG seroprevalence coincided with seasonal P. falciparum transmission peaks, even in those with no molecularly detectable parasites. At the individual level, antibody seropositivity was associated with reduced odds of contemporaneous P. falciparum (OR for PfCSP 0.51 [95%CI 0.35, 0.76], p = 0.001, PfAMA1 0.70 [95%CI 0.52, 0.93], p = 0.01, and PfMSP2 0.81 [95%CI 0.61, 1.08], p = 0.15), but not P. vivax infection (OR PvAMA1 1.02 [95%CI 0.73, 1.43], p = 0.89) indicating a potential role of immunity in protection against molecular-detectable P. falciparum parasitaemia. CONCLUSIONS: We demonstrated that integration and implementation of sample collection for molecular and serological surveillance into networks of VHV servicing hard-to-reach populations in the GMS is feasible, can capture significant levels of ongoing undetected seasonal malaria transmission and has the potential to supplement current routine RDT testing. Improving malaria surveillance by advancing the integration of molecular and serological techniques, through centralised testing approaches or novel point-of-contact tests, will advance progress, and tracking, towards malaria elimination goals in the GMS.


Asunto(s)
Malaria Falciparum , Malaria Vivax , Malaria , Estudios Transversales , Humanos , Malaria/diagnóstico , Malaria/epidemiología , Malaria Falciparum/diagnóstico , Malaria Falciparum/epidemiología , Malaria Vivax/diagnóstico , Malaria Vivax/epidemiología , Mianmar/epidemiología , Plasmodium falciparum/genética , Plasmodium vivax/genética , Prevalencia , Estudios Seroepidemiológicos
15.
J Antimicrob Chemother ; 76(3): 601-605, 2021 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-33331642

RESUMEN

OBJECTIVES: To determine the prevalence and genetic characteristics of ESBL-producing Escherichia coli in retail raw meats from Singapore markets. METHODS: A total of 634 raw meat (chicken, pork and beef) samples were collected from markets in Singapore during June 2017-October 2018. The samples were enriched overnight and then incubated on Brilliance™ ESBL Agar. Presumptive ESBL isolates were confirmed using the double-disc synergy test. Confirmed ESBL-producing E. coli were sent for WGS and bioinformatic analysis was performed. RESULTS: The prevalence of ESBL-producing E. coli in chicken, pork and beef meats was 51.2% (109/213), 26.9% (58/216) and 7.3% (15/205), respectively. A total of 225 ESBL-producing E. coli were isolated from 184 samples. ß-Lactam resistance genes were detected in all isolates. After ß-lactam resistance genes, the most common antimicrobial resistance genes detected were aminoglycoside resistance genes (92.4%). One hundred and seventy-two (76.4%), 102 (45.3%) and 52 (23.1%) isolates carried blaCTX-M genes, blaTEM genes and blaSHV genes, respectively. blaCTX-M-55 (57/225, 25.3%) and blaCTX-M-65 (40/225, 17.8%) were the most frequent ESBL genes. Colistin resistance genes (including mcr-1, mcr-3 and mcr-5) were found in 15.6% of all isolates. CONCLUSIONS: This study indicates that ESBL-producing E. coli are widely found in retail raw meats, especially chicken, in Singapore. Occurrence of MDR (resistance to at least three classes of antimicrobial) and colistin resistance genes in retail raw meat suggests potential food safety and public health risks.


Asunto(s)
Escherichia coli , Contaminación de Alimentos , Carne/microbiología , Animales , Antibacterianos/farmacología , Bovinos , Pollos , Farmacorresistencia Bacteriana , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Genómica , Prevalencia , Singapur/epidemiología , beta-Lactamasas/genética , beta-Lactamasas/farmacología
16.
Int J Mol Sci ; 22(23)2021 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-34884630

RESUMEN

Medication-related osteonecrosis of the jaw (MRONJ) is related to impaired bone healing conditions in the maxillomandibular bone region as a complication of bisphosphonate intake. Although there are several hypotheses for the onset of MRONJ symptoms, one of the possible causes is the inhibition of bone turnover and blood supply leading to bone necrosis. The optimal treatment strategy for MRONJ has not been established either. BMP-2, a member of the TGF-ß superfamily, is well known for regulating bone remodeling and homeostasis prenatally and postnatally. Therefore, the objectives of this study were to evaluate whether cyclophosphamide/zoledronate (CY/ZA) induces necrosis of the bone surrounding the tooth extraction socket, and to examine the therapeutic potential of BMP-2 in combination with the hard osteoinductive biomaterial, ß-tricalcium phosphate (ß-TCP), in the prevention and treatment of alveolar bone loss around the tooth extraction socket in MRONJ-like mice models. First, CY/ZA was intraperitoneally administered for three weeks, and alveolar bone necrosis was evaluated before and after tooth extraction. Next, the effect of BMP-2/ß-TCP was investigated in both MRONJ-like prevention and treatment models. In the prevention model, CY/ZA was continuously administered for four weeks after BMP-2/ß-TCP transplantation. In the treatment model, CY/ZA administration was suspended after transplantation of BMP-2/ß-TCP. The results showed that CY/ZA induced a significant decrease in the number of empty lacunae, a sign of bone necrosis, in the alveolar bone around the tooth extraction socket after tooth extraction. Histological analysis showed a significant decrease in the necrotic alveolar bone around tooth extraction sockets in the BMP-2/ß-TCP transplantation group compared to the non-transplanted control group in both MRONJ-like prevention and treatment models. However, bone mineral density, determined by micro-CT analysis, was significantly higher in the BMP-2/ß-TCP transplanted group than in the control group in the prevention model only. These results clarified that alveolar bone necrosis around tooth extraction sockets can be induced after surgical intervention under CY/ZA administration. In addition, transplantation of BMP-2/ß-TCP reduced the necrotic alveolar bone around the tooth extraction socket. Therefore, a combination of BMP-2/ß-TCP could be an alternative approach for both prevention and treatment of MRONJ-like symptoms.


Asunto(s)
Osteonecrosis de los Maxilares Asociada a Difosfonatos/terapia , Proteína Morfogenética Ósea 2/administración & dosificación , Trasplante Óseo/métodos , Fosfatos de Calcio/administración & dosificación , Ciclofosfamida/toxicidad , Extracción Dental/efectos adversos , Factor de Crecimiento Transformador beta/administración & dosificación , Ácido Zoledrónico/toxicidad , Pérdida de Hueso Alveolar/etiología , Pérdida de Hueso Alveolar/metabolismo , Pérdida de Hueso Alveolar/patología , Pérdida de Hueso Alveolar/terapia , Animales , Osteonecrosis de los Maxilares Asociada a Difosfonatos/etiología , Osteonecrosis de los Maxilares Asociada a Difosfonatos/metabolismo , Osteonecrosis de los Maxilares Asociada a Difosfonatos/patología , Conservadores de la Densidad Ósea/toxicidad , Fosfatos de Calcio/farmacología , Difosfonatos/toxicidad , Modelos Animales de Enfermedad , Femenino , Inmunosupresores/toxicidad , Ratones , Ratones Endogámicos C57BL , Proteínas Recombinantes/administración & dosificación , Cicatrización de Heridas
17.
BMC Oral Health ; 21(1): 2, 2021 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-33388030

RESUMEN

BACKGROUND: Oral diseases are common and widespread around the world. The most common oral diseases are preventable, and early onset is reversible. Myanmar faces many challenges in rendering oral health services, because approximately 70% of the total population resides in rural areas. These relate to the availability and accessibility of oral health services. Therefore, oral health education is one key element to prevent oral diseases and to promote oral health. METHODS: A quasi-experimental study was carried out at Basic Education Middle Schools in rural areas of Magway Township to study the effectiveness of oral health education on the knowledge and behavior of 8- to 10-year-old school children. A total of 220 school children, 110 from intervention schools and 110 from control schools, participated in this study from 2015 to 2017. Data were collected before and after intervention in the two groups by using a self-administered questionnaire. Tooth brushing method data were collected by direct observation with a checklist. Oral health education was provided at eight weekly intervals for 1 year. At one and a half years, third-time data collection was done on the intervention group to assess retention. Chi-square test, two samples t-test and one-way repeated measure ANOVA were used for data analysis. The study was approved by the Institutional Review Board of the University of Public Health in Yangon, Myanmar. RESULTS: There were significant differences between the two groups in four out of five knowledge questions (p < 0.05) and all behavior questions (p < 0.001) after intervention. A positive effect of oral health education for a period of 45 min at eight weekly intervals for 1 year was found in the intervention group. The intervention had a significant effect on the sustainability of the correct knowledge and behavior of the intervention group although the education session was stopped for 6 months (p < 0.001). Their mean knowledge and behavioral scores at three different points in time were (2.45 ± 1.12 and1.56 ± 0.90) at baseline, (3.79 ± 1.12 and 3.60 ± 1.21) at 1 year after education and (4.07 ± 0.98 and 3.24 ± 1.31) at 6 months after cessation of education, respectively. CONCLUSIONS: Repeated oral health education was effective in promoting and sustaining oral health knowledge and behavior.


Asunto(s)
Educación en Salud Dental , Cepillado Dental , Niño , Conductas Relacionadas con la Salud , Conocimientos, Actitudes y Práctica en Salud , Humanos , Mianmar , Salud Bucal , Instituciones Académicas
18.
Emerg Infect Dis ; 26(11): 2741-2745, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33079056

RESUMEN

In 2019, an outbreak of chikungunya virus infection occurred in Mandalay, Myanmar, and 3.2% of blood donors and 20.5% of patients who were children were confirmed as being infected. The prevalence rate was up to 6.3% among blood donors. The East Central/South African genotype was predominantly circulating during this outbreak.


Asunto(s)
Donantes de Sangre , Fiebre Chikungunya , Virus Chikungunya/aislamiento & purificación , Fiebre Chikungunya/epidemiología , Virus Chikungunya/genética , Niño , Brotes de Enfermedades , Genotipo , Humanos , Mianmar/epidemiología , Filogenia
19.
PLoS Med ; 17(8): e1003177, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32817632

RESUMEN

BACKGROUND: The World Health Organization has yet to endorse deployment of topical repellents for malaria prevention as part of public health campaigns. We aimed to quantify the effectiveness of repellent distributed by the village health volunteer (VHV) network in the Greater Mekong Subregion (GMS) in reducing malaria in order to advance regional malaria elimination. METHODS AND FINDINGS: Between April 2015 and June 2016, a 15-month stepped-wedge cluster randomised trial was conducted in 116 villages in Myanmar (stepped monthly in blocks) to test the effectiveness of 12% N,N-diethylbenzamide w/w cream distributed by VHVs, on Plasmodium spp. infection. The median age of participants was 18 years, approximately half were female, and the majority were either village residents (46%) or forest dwellers (40%). No adverse events were reported during the study. Generalised linear mixed modelling estimated the effect of repellent on infection detected by rapid diagnostic test (RDT) (primary outcome) and polymerase chain reaction (PCR) (secondary outcome). Overall Plasmodium infection detected by RDT was low (0.16%; 50/32,194), but infection detected by PCR was higher (3%; 419/13,157). There was no significant protection against RDT-detectable infection (adjusted odds ratio [AOR] = 0.25, 95% CI 0.004-15.2, p = 0.512). In Plasmodium-species-specific analyses, repellent protected against PCR-detectable P. falciparum (adjusted relative risk ratio [ARRR] = 0.67, 95% CI 0.47-0.95, p = 0.026), but not P. vivax infection (ARRR = 1.41, 95% CI 0.80-2.47, p = 0.233). Repellent effects were similar when delayed effects were modelled, across risk groups, and regardless of village-level and temporal heterogeneity in malaria prevalence. The incremental cost-effectiveness ratio was US$256 per PCR-detectable infection averted. Study limitations were a lower than expected Plasmodium spp. infection rate and potential geographic dilution of the intervention. CONCLUSIONS: In this study, we observed apparent protection against new infections associated with the large-scale distribution of repellent by VHVs. Incorporation of repellent into national strategies, particularly in areas where bed nets are less effective, may contribute to the interruption of malaria transmission. Further studies are warranted across different transmission settings and populations, from the GMS and beyond, to inform WHO public health policy on the deployment of topical repellents for malaria prevention. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry (ACTRN12616001434482).


Asunto(s)
Servicios de Salud Comunitaria/métodos , Repelentes de Insectos/administración & dosificación , Malaria Falciparum/epidemiología , Malaria Falciparum/prevención & control , Malaria Vivax/epidemiología , Malaria Vivax/prevención & control , Voluntarios , Administración Tópica , Adolescente , Adulto , Niño , Análisis por Conglomerados , Servicios de Salud Comunitaria/economía , Análisis Costo-Beneficio/métodos , Femenino , Humanos , Repelentes de Insectos/economía , Malaria Falciparum/economía , Malaria Vivax/economía , Masculino , Mianmar/epidemiología , Embarazo , Resultado del Tratamiento , Adulto Joven
20.
Cancer ; 126(13): 3021-3030, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32320048

RESUMEN

BACKGROUND: Despite a protracted disease course and multiple available therapies, patients with well-differentiated neuroendocrine tumors (NETs) inevitably experience disease progression. Programmed death-ligand 1 (PD-L1) has been associated with NET progression and prognosis. The multicohort, phase 1 KEYNOTE-028 study (ClinicalTrials.gov identifier NCT02054806) evaluated the activity and safety of the anti-programmed cell death protein 1 immunotherapy pembrolizumab in patients with well-differentiated or moderately-differentiated NETs. METHODS: Patients with PD-L1-positive, locally advanced or metastatic carcinoid or well-differentiated or moderately-differentiated pancreatic NETs (pNETs) were enrolled into separate cohorts and received pembrolizumab at a dose of 10 mg/kg every 2 weeks for up to 2 years. The objective response rate was the primary endpoint (as per Response Evaluation Criteria in Solid Tumors version 1.1, by investigator review). Safety was a secondary endpoint. RESULTS: Of 170 and 106 patients, respectively, who had evaluable samples among those screened for the carcinoid and pNET cohorts, 21% and 25%, respectively, had PD-L1-positive tumors; of these, 25 and 16 patients, respectively, were eligible and treated. The median follow-up was 20 months (range, 2-35 months) and 21 months (range, 5-32 months), respectively. The objective response rate was 12.0% (95% CI, 2.5%-31.2%) and 6.3% (95% CI, 0.2%-30.2%), respectively; 3 partial responses occurred among the carcinoid cohort and 1 among the pNET cohort. The median duration of response in the carcinoid cohort was 9.2 months (range, 6.9-11.1 months), and was not reached in the pNET cohort. No complete responses occurred. Treatment-related adverse events occurred in 68% and 69% of patients, respectively, most often diarrhea (7 patients in the carcinoid cohort and 4 patients in the pNET cohort) and fatigue (6 patients in each cohort). Hypothyroidism was the most common immune-mediated adverse event (5 patients in the carcinoid cohort and 2 patients in the pNET cohort). CONCLUSIONS: Pembrolizumab demonstrated antitumor activity in a subset of patients with NETs and was well-tolerated.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Tumor Carcinoide/tratamiento farmacológico , Tumores Neuroendocrinos/tratamiento farmacológico , Neoplasias Pancreáticas/tratamiento farmacológico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Adulto , Anciano , Anciano de 80 o más Años , Alanina Transaminasa/metabolismo , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Antineoplásicos Inmunológicos/administración & dosificación , Antineoplásicos Inmunológicos/efectos adversos , Aspartato Aminotransferasas/metabolismo , Tumor Carcinoide/química , Tumor Carcinoide/patología , Estudios de Cohortes , Diarrea/inducido químicamente , Progresión de la Enfermedad , Esquema de Medicación , Fatiga/inducido químicamente , Femenino , Estudios de Seguimiento , Humanos , Hipotiroidismo/inducido químicamente , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/química , Tumores Neuroendocrinos/patología , Neoplasias Pancreáticas/química , Neoplasias Pancreáticas/patología
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