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1.
BMC Genomics ; 25(1): 336, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570743

RESUMEN

The Asian tiger mosquito, Aedes albopictus, is a global invasive species, notorious for its role in transmitting dangerous human arboviruses such as dengue and Chikungunya. Although hematophagous behavior is repulsive, it is an effective strategy for mosquitoes like Aedes albopictus to transmit viruses, posing a significant risk to human health. However, the fragmented nature of the Ae. albopictus genome assembly has been a significant challenge, hindering in-depth biological and genetic studies of this mosquito. In this research, we have harnessed a variety of technologies and implemented a novel strategy to create a significantly improved genome assembly for Ae. albopictus, designated as AealbF3. This assembly boasts a completeness rate of up to 98.1%, and the duplication rate has been minimized to 1.2%. Furthermore, the fragmented contigs or scaffolds of AealbF3 have been organized into three distinct chromosomes, an arrangement corroborated through syntenic plot analysis, which compared the genetic structure of Ae. albopictus with that of Ae. aegypti. Additionally, the study has revealed a phylogenetic relationship suggesting that the PGANT3 gene is implicated in the hematophagous behavior of Ae. albopictus. This involvement was preliminarily substantiated through RNA interference (RNAi) techniques and behavioral experiment. In summary, the AealbF3 genome assembly will facilitate new biological insights and intervention strategies for combating this formidable vector of disease. The innovative assembly process employed in this study could also serve as a valuable template for the assembly of genomes in other insects characterized by high levels of heterozygosity.


Asunto(s)
Aedes , Mosquitos Vectores , Animales , Humanos , Mosquitos Vectores/genética , Filogenia , Conducta Alimentaria
2.
Immunity ; 42(4): 613-26, 2015 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-25862091

RESUMEN

Epigenetic regulation of lineage-specific genes is important for the differentiation and function of T cells. Ten-eleven translocation (Tet) proteins catalyze 5-methylcytosine (5 mC) conversion to 5-hydroxymethylcytosine (5 hmC) to mediate DNA demethylation. However, the roles of Tet proteins in the immune response are unknown. Here, we characterized the genome-wide distribution of 5 hmC in CD4(+) T cells and found that 5 hmC marks putative regulatory elements in signature genes associated with effector cell differentiation. Moreover, Tet2 protein was recruited to 5 hmC-containing regions, dependent on lineage-specific transcription factors. Deletion of Tet2 in T cells decreased their cytokine expression, associated with reduced p300 recruitment. In vivo, Tet2 plays a critical role in the control of cytokine gene expression in autoimmune disease. Collectively, our findings suggest that Tet2 promotes DNA demethylation and activation of cytokine gene expression in T cells.


Asunto(s)
Citocinas/biosíntesis , Proteínas de Unión al ADN/inmunología , Epigénesis Genética/inmunología , Proteínas Proto-Oncogénicas/inmunología , Células TH1/inmunología , Células Th17/inmunología , 5-Metilcitosina/análogos & derivados , Animales , Diferenciación Celular , Citocinas/inmunología , Citosina/análogos & derivados , Citosina/inmunología , Citosina/metabolismo , ADN/inmunología , ADN/metabolismo , Metilación de ADN , Proteínas de Unión al ADN/genética , Dioxigenasas , Proteína p300 Asociada a E1A/genética , Proteína p300 Asociada a E1A/inmunología , Regulación de la Expresión Génica , Genoma , Humanos , Ratones , Ratones Transgénicos , Proteínas Proto-Oncogénicas/genética , Factor de Transcripción STAT4/genética , Factor de Transcripción STAT4/inmunología , Proteínas de Dominio T Box/genética , Proteínas de Dominio T Box/inmunología , Células TH1/citología , Células TH1/enzimología , Células Th17/citología , Células Th17/enzimología
3.
Eur J Clin Microbiol Infect Dis ; 42(5): 529-541, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36856898

RESUMEN

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection is a major public health threat in the world. To inform the prevention and control of CRKP infection in hospitals, this study analyzed the factors associated with CRKP infection and resistance to carbapenems in K. pneumoniae. This case-case-control study was carried out in a large general hospital in China from January 2016 to December 2018, comprising 494 hospitalized patients infected with CRKP (case group 1) and 2429 hospitalized patients infected with carbapenem-susceptible K. pneumoniae (CSKP, case group 2). We selected control groups from hospitalized patients without K. pneumoniae infections for the two case groups separately, with a 1:3 case-control ratio, to analyze the risk factors of the two case groups using the conditional logistic regression. Multivariate analysis showed that the risk factors of CRKP infection were intensive care unit (ICU) admission (odds ratio [OR], 6.85; 95% confidence interval [CI], 4.90-9.58; P < 0.001), respiratory failure (OR, 1.93; 95% CI, 1.34-2.77; P < 0.001), age-adjusted Charlson comorbidity index (aCCI; OR, 1.08; 95% CI, 1.02-1.15; P = 0.007), admission from the Emergency (OR, 1.37; 95% CI, 1.02-1.85; P = 0.036), and imipenem use (OR, 1.80; 95% CI, 1.30-2.49; P < 0.001). Among the aforementioned five risk factors, aCCI (OR, 1.09; 95% CI, 1.06-1.13; P < 0.001) was also identified as a risk factor of CSKP infections in multivariate analysis. The risk factors for resistance to carbapenems in K. pneumoniae were ICU admission, respiratory failure, admission from the Emergency, and imipenem use.


Asunto(s)
Enterobacteriaceae Resistentes a los Carbapenémicos , Infección Hospitalaria , Infecciones por Klebsiella , Humanos , Estudios de Casos y Controles , Antibacterianos/efectos adversos , Klebsiella pneumoniae , Hospitales Generales , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/epidemiología , Farmacorresistencia Bacteriana , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Imipenem/farmacología , Factores de Riesgo , Infección Hospitalaria/epidemiología , Infección Hospitalaria/tratamiento farmacológico , Atención a la Salud
4.
J Org Chem ; 85(8): 5231-5244, 2020 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-32186180

RESUMEN

Chiral phosphoric acid-catalyzed biomimetic asymmetric [4 + 2] cycloaddition of ortho-alkenyl naphthols/phenols and ortho-quinone methides (o-QMs) has been demonstrated to afford various important 2,3,4-trisubstituted chromans in high yields with excellent enantio- and diastereoselectivities (up to 99% yield, 99% ee, >20:1 dr). Notably, this methodology not only enabled access to the trans-cis chiral trisubstituted chromans from 1-alkenyl 2-naphthols but also is compatible with 2-alkenyl 1-naphthols and phenols to deliver trans-trans chiral trisubstituted chromans.

5.
Org Biomol Chem ; 18(16): 3117-3124, 2020 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-32253417

RESUMEN

A SPINOL-derived chiral phosphoric acid catalyzed asymmetric formal [2 + 3]-annulation of in situ generated alkynyl imines and 1,4-dithiane-2,5-diol has been developed to afford enantiopure α-alkynylated thiazolidones with up to 72% yield and 98.5 : 1.5 er. This tandem annulation involved a tandem S-addition of alkynyl imines/intramolecular acetalization, followed by PDC-mediated oxidation. The α-alkynylated thiazolidones could facilely afford the corresponding chiral α-alkynylated or α-alkenylated cyclic sulfoxides via further elaboration.

6.
Angew Chem Int Ed Engl ; 58(14): 4710-4713, 2019 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-30741497

RESUMEN

The first Pd-catalyzed asymmetric allenylic [4+1] cycloaddition was successfully developed. Alternatively, tuning the Pd catalyst switched the reactivity toward an unprecedented [4+3] cycloaddition/cross-coupling. Ligands play a vital role in controlling the reaction pathway, allowing highly selective access to different products from identical substrates. Biological evaluation of the obtained compounds led to the discovery of new antitumor targets. A possible mechanism is proposed, suggesting two interesting catalytic cycles for the cycloaddition with palladium-butadienyls. This study also demonstrated the potential and utility of allenic esters as 1,4-biselectrophiles and C4 synthons for participating in cycloaddition reactions.

7.
Angew Chem Int Ed Engl ; 58(44): 15819-15823, 2019 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-31489736

RESUMEN

The strong binding ability of P-ylides with transition metals limits the utilization of stabilized P-ylide as nucleophiles in asymmetric organometallic catalysis. Herein we describe the first rhodium-catalyzed asymmetric ring-opening reaction of P-ylides utilizing oxabicyclic alkenes as the electrophilic partner. Various P-ylides including ester-, ketone- and amide-style P-ylides are all applicable. This asymmetric reaction occurs through the cleavage of two bridgehead C-O bonds and the formation of two C-C bonds, and oxabenzonorbornadienes are used as 1,4-biselectrophiles, thus providing access to benzonorcaradienes in good yields with high enantioselectivity and perfect diastereoselectivity. The present protocol also constitutes the first highly enantioselective direct catalytic asymmetric cyclopropanation of stabilized P-ylide nucleophiles.

8.
Clin Infect Dis ; 67(suppl_2): S225-S230, 2018 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-30423052

RESUMEN

Background: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a major health threat, but the economic impact of carbapenem resistance in K. pneumoniae infections remains largely uninvestigated. Methods: We constructed a retrospective cohort of all patients hospitalized at West China Hospital in 2017 who had CRKP- or carbapenem-susceptible K. pneumoniae (CSKP)-positive clinical samples. Propensity score matching (PSM) was used to control the impact of potential confounding variables, including demographics, comorbidities, and treatment, and to observe the impact of factors other than length of stay (LOS). Patients who survived were subjected to subgroup analyses stratified by infection type. Results: There were 267 patients with CRKP and 1328 with CSKP. Patients with CRKP had a higher crude in-hospital mortality rate (14.61% vs 5.65%, P < .05) and longer LOS (median, 31 vs 19 days; P < .05). PSM for demographics, comorbidities, and treatment generated 237 pairs. Patients with CRKP had higher medical costs than those with CSKP during the entire hospitalization (median, in US dollars, $22962 vs $11755, respectively; P < .05) and during the period after infection (median, $9215 vs $6904, respectively; P < .05). When LOS was matched, patients with CRKP still had high excess costs compared to those with CSKP (median, $22917 vs $13851, respectively, for the entire hospitalization, P < .05; $9101 vs $7001, respectively, after infection, P < .05). For infection type, the sample size generated sufficient power to compare only the patients with pneumonia. For surviving patients, high excess costs were observed in those with pneumonia caused by CRKP as compared to CSKP ($21890 vs $11698, respectively, for the entire hospitalization, P < .05; $9773 vs $5298, respectively, after infection, P < .05). Medicines other than antibacterial agents and nonmedicinal therapies contributed most (57.8%) of the excess costs associated with CRKP. Conclusions: Carbapenem resistance in K. pneumoniae was associated with increased medical costs not accounted for by the cost of antimicrobial therapy.


Asunto(s)
Antibacterianos/farmacología , Carbapenémicos/farmacología , Farmacorresistencia Bacteriana , Costos de Hospital , Hospitalización/economía , Infecciones por Klebsiella/economía , Adulto , Anciano , Estudios de Casos y Controles , China/epidemiología , Femenino , Mortalidad Hospitalaria , Humanos , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/mortalidad , Klebsiella pneumoniae/efectos de los fármacos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
9.
Proc Natl Acad Sci U S A ; 112(44): E5907-15, 2015 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-26483478

RESUMEN

The Asian tiger mosquito, Aedes albopictus, is a highly successful invasive species that transmits a number of human viral diseases, including dengue and Chikungunya fevers. This species has a large genome with significant population-based size variation. The complete genome sequence was determined for the Foshan strain, an established laboratory colony derived from wild mosquitoes from southeastern China, a region within the historical range of the origin of the species. The genome comprises 1,967 Mb, the largest mosquito genome sequenced to date, and its size results principally from an abundance of repetitive DNA classes. In addition, expansions of the numbers of members in gene families involved in insecticide-resistance mechanisms, diapause, sex determination, immunity, and olfaction also contribute to the larger size. Portions of integrated flavivirus-like genomes support a shared evolutionary history of association of these viruses with their vector. The large genome repertory may contribute to the adaptability and success of Ae. albopictus as an invasive species.


Asunto(s)
Aedes/genética , Evolución Molecular , Genoma de los Insectos , Aedes/clasificación , Aedes/fisiología , Animales , Filogenia
10.
J Am Chem Soc ; 139(20): 7095-7103, 2017 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-28448135

RESUMEN

Lycopodium alkaloids with structural diversity and biological significance have been stimulating an increasing interest in the synthetic and medicinal communities, in which inspiration and exploration of their related biogenetic relationship generally constitute one of the major concerns. Driven by the plausible biogenetic entry to lycojaponicumin D as the first member of Lycopodium alkaloids having a structurally unusual C3-C13-linked scaffold, a new connection with lycodoline has been proposed and discovered on the basis of the design of an unprecedented bioinspired tandem fragmentation/Mannich reaction. Initiated by expeditious assembly of bridgehead heterofunctionalization in the [3.3.1] bicyclic system of lycodoline, a novel tandem palladium-mediated oxidative dehydrogenation/hetero-Michael reaction has been developed for the strain-driven formation of the C-heteroatom bond, leading to a new approach to conformationally rigid bridgehead heteroquaternary carbons. The present unified strategy provides a scenario for the divergent total syntheses of nine natural Lycopodium alkaloids and four unnatural C12 epimers, wherein (±)-lycojaponicumin D and six lycodoline-type alkaloids have been synthetically achieved for the first time.


Asunto(s)
Alcaloides/síntesis química , Lycopodium/química , Alcaloides/química , Cristalografía por Rayos X , Ciclización , Modelos Moleculares , Estructura Molecular , Estereoisomerismo
11.
J Org Chem ; 82(10): 5433-5440, 2017 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-28421762

RESUMEN

A novel enantioselective [4 + 2] annulation of the allenoates having a unique positive ortho-effect with in situ generated ortho-quinone methides has been developed under the catalysis of Cinchona alkaloid. This chiral amine-catalyzed reaction provides an alternative route to asymmetric catalytic construction of synthetically interesting, highly functionalized chiral chromans in good to excellent enantioselectivities (up to 97% ee).

12.
J Org Chem ; 81(6): 2598-606, 2016 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-26892163

RESUMEN

A novel DBU-mediated stereoselective spirocyclopropanation of para-quinone methides with sulfonium salts has been developed on the basis of the mode involving a 1,6-conjugate addition/intramolecular dearomatizing cyclization cascade. This reaction provides a mild and effective method for the assembly of synthetically and structurally interesting spirocyclopropanyl para-dienones. The feasibility for the enantioselective access to such functionalized para-dienones has also been explored by using the axially chiral sulfonium salt. Importantly, the regioselective ring openings of the related spirocyclopropanyl para-dienones have been achieved divergently.

13.
J Org Chem ; 81(13): 5655-62, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27224285

RESUMEN

A novel strategy based on phase transfer catalysis for the diastereoselective and enantioselective direct assembly of unsymmetric ß,ß-diaryl-α-amino acid esters via 1,6-conjugate addition of para-quinone methides and glycine derivatives is described. This protocol also provides an alternative route to the synthetically interesting functionalized chiral tetrahydroisoquinoline and its analogues.

14.
J Med Virol ; 86(8): 1428-36, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25025105

RESUMEN

The Asian tiger mosquito, Aedes albopictus isa major vector of dengue in mainland China. Dengue epidemics have spread from the southern coastal regions to the relatively northern and western regions since 1990s. Dengue has become an emerging public health problem in the southern coastal regions. microRNAs(miRNAs) are short non-coding RNAs that regulate gene expression at the post transcription allevel. A highly abundant miRNA, miR-252, was induced more than threefold after dengue virus serotype 2 (DENV-2) infection in the Ae. albopictus C6/36 cellline. Transfection with miR-252 inhibitor resulted in the increase of DENV-2 RNA copies and the up-regulation of DENV-2 envelop protein(E protein) expression, whereas over expression of miR-252 with its mimic decreased DENV RNA copies and the down-regulation of E protein expression. MiR-252 mimic reduced luciferase activity of a luciferase reporter that contained the predicted miR-252 target on the DENV-2 envelope gene sequence. The present results indicated that the miR-252 of Ae. albopictus could regulate the gene expression of DENV-2 E protein and may act asa cellular antiviral regulator in Ae. albopictus.


Asunto(s)
Aedes/genética , Virus del Dengue/fisiología , Regulación de la Expresión Génica , Interacciones Huésped-Patógeno , MicroARNs/metabolismo , Proteínas del Envoltorio Viral/antagonistas & inhibidores , Replicación Viral , Animales , Fusión Artificial Génica , Línea Celular , Femenino , Perfilación de la Expresión Génica , Genes Reporteros , Luciferasas/análisis , Luciferasas/genética , MicroARNs/genética , Proteínas del Envoltorio Viral/genética
15.
Hepatogastroenterology ; 61(130): 391-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24901148

RESUMEN

BACKGROUND/AIMS: In the last 10 years, the early patient outcome of liver transplantation in children have significantly improved. Now the overall outcomes of pediatric LT are promising. METHODOLOGY: In this study, we review the outcome of all pediatric liver transplants performed at our center and analyze our experiences with pediatric liver transplant. Of the 34 liver transplant recipients, 26 were highly urgent (19.7%). RESULTS: Actuarial patient survival rates at 6, 12, and 36 months was 82.9%, 79.8% and 72.2%, respectively. Indications for liver transplant were biliary atresia (n = 22), Wilson's disease (n = 4), glycogen storage disease (n = 3), portal vein cavernous transformation (PVCT) (n = 3), fulminant liver failure (n = 1), and cryptogenic cirrhosis (n = 1). The main complications were surgical complications (including biliary complications, portal vein or arterial complications, intestinal perforation, postoperative bleeding, of which 20% required reoperation) and infections. Cyclosporine was the primary immunosuppressive agent used in 70.6% of patients, with a 26.5% incidence of acute allograft rejection within the first six months. One children underwent re-transplant as a result of hepatic artery thrombosis. Nine children died during followup. They were related to portal vein thrombosis (one), chronic rejection (one), sepsis (one), post-transplant lymphoproliferative disease (one) and so on. CONCLUSIONS: The overall outcomes of pediatric liver transplantation at our center are promising. Advances in post-transplant care and monitoring of the recipients, technical refinements enable these results.


Asunto(s)
Hepatopatías/cirugía , Trasplante de Hígado/métodos , Adolescente , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , Infecciones Bacterianas/etiología , Infecciones Bacterianas/microbiología , Niño , Preescolar , Farmacorresistencia Bacteriana , Femenino , Humanos , Lactante , Estimación de Kaplan-Meier , Trasplante de Hígado/efectos adversos , Donadores Vivos , Masculino , Pruebas de Sensibilidad Microbiana , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/microbiología
16.
Aging (Albany NY) ; 16(5): 4518-4540, 2024 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-38475660

RESUMEN

Along with the increasing knowledge of long noncoding RNA, the interaction between the long noncoding RNA (lncRNA) and tumor immune infiltration is increasingly valued. However, there is a lack of understanding of correlation between regulation of specific lncRNAs and tumor-infiltrating macrophages within melanoma. In this research, a macrophage associated lncRNA signature was identified by multiple machine learning algorithms and the robust and effectiveness of signature also validated in other independent datasets. The signature contained six specific lncRNAs (PART1, LINC00968, LINC00954, LINC00944, LINC00518 and C20orf197) was constructed, which could diagnose melanoma and predict the prognosis of patients. Moreover, our signature achieves higher accuracy than the previous well-established markers and regarded as an independent prognostic indicator. The pathway enrichment revealed that these lncRNAs were closely correlated with many immune processes. In addition, the signature was associated with different immune microenvironment and applied to predict response of immune checkpoint inhibitor therapy (low risk of patients well respond to anti-PD-1 therapy and high risk is insensitive to anti-CTLA-4 therapy). Therefore, our finding supplies a more accuracy and effective lncRNA signature for tumor-infiltrating macrophages targeting treatment approaches and affords a new clinical application for predicting the response of immunotherapies in melanomas.


Asunto(s)
Melanoma , ARN Largo no Codificante , Neoplasias Cutáneas , Humanos , Melanoma/genética , Melanoma/terapia , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/terapia , ARN Largo no Codificante/genética , Pronóstico , Inmunoterapia , Macrófagos , Microambiente Tumoral/genética
17.
Chemistry ; 19(22): 7143-50, 2013 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-23559455

RESUMEN

Highly enantioselective cross-aldol reactions between acetaldehyde and activated acyclic ketones are reported for the first time. Various acyclic ketones, such as saturated and unsaturated keto esters, reacted with acetaldehyde in the presence of a chiral primary amine and a Brønsted acid to afford optically enriched tertiary alcohols in good yields and with excellent enantioselectivities. Trifluoromethyl ketones were tolerable under the reaction conditions, thereby affording the trifluoromethyl carbinol in good-to-excellent yields and enantioselectivities. Structural modification of the chiral amines from the same chiral source switched the stereoselectivity of the products. The utility of aldol chemistry was demonstrated in the brief synthesis of functionally enriched δ-lactones. Theoretical calculations on the transition-state structure indicated that the protonated tertiary amine could effectively activate the carbonyl group of a keto ester to promote the addition process through hydrogen-bonding interaction and, simultaneously, provide an appropriate attacking pattern for the approach of the keto ester to the enamine, which is formed from acetaldehyde and the chiral catalyst, on a particular face, resulting in high enantioselectivity.

18.
Nat Plants ; 9(9): 1481-1499, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37640933

RESUMEN

Phenolic acids (PAs) secreted by donor plants suppress the growth of their susceptible plant neighbours. However, how structurally diverse ensembles of PAs are perceived by plants to mediate interspecific competition remains a mystery. Here we show that a plant stress granule (SG) marker, RNA-BINDING PROTEIN 47B (RBP47B), is a sensor of PAs in Arabidopsis. PAs, including salicylic acid, 4-hydroxybenzoic acid, protocatechuic acid and so on, directly bind RBP47B, promote its phase separation and trigger SG formation accompanied by global translation inhibition. Salicylic acid-induced global translation inhibition depends on RBP47 family members. RBP47s regulate the proteome rather than the absolute quantity of SG. The rbp47 quadruple mutant shows a reduced sensitivity to the inhibitory effect of the PA mixture as well as to that of PA-rich rice when tested in a co-culturing ecosystem. In this Article, we identified the long sought-after PA sensor as RBP47B and illustrated that PA-induced SG-mediated translational inhibition was one of the PA perception mechanisms.


Asunto(s)
Arabidopsis , Ecosistema , Arabidopsis/genética , Ecología , Salicilatos
19.
Pediatr Res ; 71(6): 638-44, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22476047

RESUMEN

INTRODUCTION: To our knowledge, elucidating the immune pathogenesis of disease, especially characteristic T-cell and natural killer (NK) cell expansions, has not been performed before now. We investigated the role of T lymphocytes and NK lymphocytes in the destruction of extrahepatic bile ducts of patients with biliary atresia. METHODS: Lymphocytes from the liver and extrahepatic bile duct remnants of patients with biliary atresia were characterized by immunofluorescence staining, fluorescence-activated cell sorter analysis, and real-time reverse-transcriptase PCR. Cholangiocyte lysis assays were performed to confirm cytotoxicity of activated hepatic NK lymphocytes or CD8(+) cells. RESULTS: The inflammatory milieu from portal tracts and/or biliary remnants consisted of greater numbers of Kupffer cells, T lymphocytes, and NK lymphocytes in the patients with biliary atresia as compared with the cholestatic and noncholestatic controls. In patients with biliary atresia, expression of NK or CD8+ costimulatory molecules was upregulated as compared with controls. Hepatic NK lymphocytes or CD8(+) cells from patients with biliary atresia were demonstrated to be cytotoxic to the duct epithelium. DISCUSSION: Specific immune responses from NK and CD8(+) cells were involved in the injury to the duct epithelium and play a significant role in the phenotype of experimental biliary atresia.


Asunto(s)
Conductos Biliares Extrahepáticos/lesiones , Conductos Biliares Extrahepáticos/patología , Atresia Biliar/complicaciones , Linfocitos T CD8-positivos/patología , Células Asesinas Naturales/patología , Conductos Biliares Extrahepáticos/metabolismo , Atresia Biliar/metabolismo , Atresia Biliar/patología , Antígenos CD28/metabolismo , Linfocitos T CD8-positivos/metabolismo , Antígeno CTLA-4/metabolismo , Estudios de Casos y Controles , Epitelio/metabolismo , Epitelio/patología , Humanos , Lactante , Recién Nacido , Inflamación/metabolismo , Inflamación/patología , Células Asesinas Naturales/metabolismo , Macrófagos del Hígado/metabolismo , Macrófagos del Hígado/patología
20.
Front Pediatr ; 10: 1076618, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36619502

RESUMEN

Objective: The present study intends to analyze the targeted surveillance and risk factors for healthcare-associated infection (HAI) in patients with pulmonary arterial hypertension associated with congenital heart disease (CHD-PAH) in a Pediatric intensive care unit (PICU), and provide basis for formulating relevant prevention and control measures of HAI. Methods: Children (≤14 years old) who were admitted to the PICU for ≥2 calendar days from January 2018 to December 2021 were included. Targeted surveillance of HAI was described. Results: A total of 7,828 patients in PICU were monitored, and the total hospitalization days of the patients were 36,174. 108 cases of HAI occurred, with a per-case infection rate of 1.38% and a per-thousand day infection rate of 2.99. 1,129 patients with CHD-PAH were included, among which the total hospitalization days were 1,483. In this subpopulation, 38 cases of HAI were diagnosed, with a per-case infection rate of 3.37% and a per-thousand day infection rate of 25.62. The main site of HAI was lower respiratory tract (43.51%), followed by blood infection (34.26%) and surgical site infection (9.26%). 36 strains of pathogenic bacteria were detected from patients with HAI. The top three pathogens with the highest detection rate were Klebsiella pneumoniae (6 episodes, 16.67%), Enterococcus faecium (6 episodes, 16.67%) and Acinetobacter baumannii (4 episodes, 11.11%). The incidence of VAP, CAUTI and CLABSI was 2.78, 0.08 and 1.66 per 1,000 catheter days respectively. Analysis revealed that patients with CHD-PAH were younger and prone to receive surgical corrections. CHD-PAH could significantly increase the length of ICU stay, ventilator days, times of central venous catheterization and central venous catheterization days. The choice of different central venous catheter types differed significantly between the two groups. Conclusion: Patients with CHD-PAH are characterized with excessive central venous catheterization operations, prolonged indwelling time, and more types of catheterization, which are considered to be risk factors for HAI, thus increasing the length of hospital stay. The clinical etiology is mainly G-bacteria, which requires reasonable selection of antibiotics and strict aseptic operation. Limiting unnecessary invasive procedures is helpful for reducing the incidence of postoperative HAI in PICU.

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