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1.
Zookeys ; 1195: 139-155, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38525353

RESUMEN

Himalayan shrews of the genus Soriculus (Soricidae, Eulipotyphla), currently represented by four nominal species, are endemic to the Himalayas and the Gaoligong Mountains. In April 2022 and April 2023, a total of 10 specimens of Soriculus were collected from Beibeng and Damu, Medog County, Tibet, China. The morphology of the specimens was compared with the four recognised species of the genus Soriculus. Additionally, two mitochondrial (Cyt b and 12S) and three nuclear (APOB, BRCAI and RAG2) genes were sequenced to test the phylogenetic relationships of these specimens with the other species. Our results indicate that these specimens represent a distinct species, Soriculusbeibengensissp. nov., which is formally described here. The new species is distinguished from the other Soriculus species by the combination of darker pelages, smaller size, the relatively stubby nasal and the widened posterior processes of incisors. Phylogenetic analyses revealed the new species is sister to S.minor. The p-distance of Cyt b gene between S.beibengensis sp. nov. and other nominal Soriculus species ranges from 9.1-16.3%. This new species has a known distribution at an elevation of 1,500-2,125 m in Medog County, Tibet, China. The discovery of this new species from Medog County has important implications for interpreting small mammal biogeographic patterns in the eastern Himalaya and the mountain chains of south-west China.

2.
Primates ; 65(1): 15-19, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38010457

RESUMEN

White-cheeked macaque Macaca leucogenys is a recently described primate species discovered by camera-trap surveys in the Medog region in 2015. The species was thought to be narrowly distributed in southeastern Tibet. However, knowledge on the distribution and conservation of the species is quite limited. Based on a systematic camera-trapping survey, we report the occurrence of the species in the Gaoligong Mountains, over 350 km southeast of the nearest known population. We recorded 3025 photographs of white-cheeked macaques representing 481 independent records from 59 camera-trap stations with total trapping efforts of 18,437 camera days. Notably, part of the newly discovered locations of the white-cheeked macaque are outside of nature reserves without any formal protection and management. Our survey also confirms the occurrence of ten primate species in the Gaoligong Mountains, accounting for 35.7% of China's primates, including the Skywalker hoolock gibbon Hoolock tianxing and the Myanmar snub-nosed monkey Rhinopithecus strykeri etc. These findings reveal a new distribution record for the white-cheeked macaque and further highlight the conservation values of Gaoligong Mountains for globally threatened primate species. We also provide a preliminary report on the daily activity patterns of this endangered species, which enriches the bio-ecological data of the poorly studied species. We believe the report has significant implications for understanding the ecology of the species and improving conservation planning.


Asunto(s)
Hylobatidae , Presbytini , Animales , Macaca , Especies en Peligro de Extinción , Tibet , Hylobates , China
3.
Sensors (Basel) ; 23(19)2023 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-37837139

RESUMEN

In recent decades, the rapid development of the global economy has led to a substantial increase in energy consumption, subsequently resulting in the emission of a significant quantity of toxic gases into the environment. So far, gas sensors based on polymer field-effect transistors (PFETs), a highly practical and cost-efficient strategy, have garnered considerable attention, primarily attributed to their inherent advantages of offering a plethora of material choices, robust flexibility, and cost-effectiveness. Notably, the development of functional organic semiconductors (OSCs), such as poly(3-hexylthiophene-2,5-diyl) (P3HT), has been the subject of extensive scholarly investigation in recent years due to its widespread availability and remarkable sensing characteristics. This paper provides an exhaustive overview encompassing the production, functionalization strategies, and practical applications of gas sensors incorporating P3HT as the OSC layer. The exceptional sensing attributes and wide-ranging utility of P3HT position it as a promising candidate for improving PFET-based gas sensors.

6.
J Exp Med ; 220(8)2023 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-37097293

RESUMEN

The formation of germinal centers (GCs) is crucial for humoral immunity and vaccine efficacy. Constant stimulation through microbiota drives the formation of constitutive GCs in Peyer's patches (PPs), which generate B cells that produce antibodies against gut antigens derived from commensal bacteria and infectious pathogens. However, the molecular mechanism that regulates this persistent process is poorly understood. We report that Ewing Sarcoma Breakpoint Region 1 (EWSR1) is a brake to constitutive GC generation and immunoglobulin G (IgG) production in PPs, vaccination-induced GC formation, and IgG responses. Mechanistically, EWSR1 suppresses Bcl6 upregulation after antigen encounter, thereby negatively regulating induced GC B cell generation and IgG production. We further showed that tumor necrosis factor receptor-associated factor (TRAF) 3 serves as a negative regulator of EWSR1. These results established that the TRAF3-EWSR1 signaling axis acts as a checkpoint for Bcl6 expression and GC responses, indicating that this axis is a therapeutic target to tune GC responses and humoral immunity in infectious diseases.


Asunto(s)
Ganglios Linfáticos Agregados , Factor 3 Asociado a Receptor de TNF , Antígenos/metabolismo , Linfocitos B , Centro Germinal , Inmunoglobulina G/metabolismo , Factor 3 Asociado a Receptor de TNF/metabolismo , Humanos
7.
Dev Cell ; 58(9): 760-778.e6, 2023 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-37054705

RESUMEN

The STING-mediated type I interferon (IFN) signaling pathway has been shown to play critical roles in antitumor immunity. Here, we demonstrate that an endoplasmic reticulum (ER)-localized JmjC domain-containing protein, JMJD8, inhibits STING-induced type I IFN responses to promote immune evasion and breast tumorigenesis. Mechanistically, JMJD8 competes with TBK1 for binding with STING, blocking STING-TBK1 complex formation and restricting type I IFN and IFN-stimulated gene (ISG) expression as well as immune cell infiltration. JMJD8 knockdown improves the efficacy of chemotherapy and immune checkpoint therapy in treating both human and mouse breast cancer cell-derived implanted tumors. The clinical relevance is highlighted in that JMJD8 is highly expressed in human breast tumor samples, and its expression is inversely correlated with that of type I IFN and ISGs as well as immune cell infiltration. Overall, our study found that JMJD8 regulates type I IFN responses, and targeting JMJD8 triggers antitumor immunity.


Asunto(s)
Neoplasias de la Mama , Evasión Inmune , Animales , Femenino , Humanos , Ratones , Retículo Endoplásmico/metabolismo , Inmunidad Innata , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Transducción de Señal/genética
8.
J Musculoskelet Neuronal Interact ; 22(4): 546-561, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36458392

RESUMEN

OBJECTIVE: To evaluate the mechanism of Bone Marrow Mesenchymal Stem Cells (BMSCs) in regulating NF-κB signal pathway by targeting miR-449a. METHODS: Stem cells were transfected by over-expressing and inhibiting miR-449a to detect the levels and viability of miR-449a in stem cells after transfection. Stem cells and neurons were co-cultured in vitro to evaluate the in vitro mechanism of stem cells over-expressing miR-449a on neurons. RESULTS: After the addition of neurons, the neuronal activity of miR-449a over-expression group increased significantly, the expression of NF-κB signal pathway proteins (IκBα, p50, and p65) decreased, and the inflammatory cytokines (TNF-α and IL-1ß) decreased significantly (P<0.05). In vivo experiments in rats also showed that rats were unresponsive, did not chirp or elude after being stimulated. After stem cell therapy, the weight and response of rats gradually returned to normal levels. miR-449a expression significantly increased in the stem cell + miR-449a over-expression group, expression of NF-κB signal pathway proteins (IκBα, p50, and p65) decreased, inflammatory cytokines (TNF-α and IL-1ß) significantly decreased, and cell activity significantly increased (P<0.05). CONCLUSIONS: BMSCs can modulate NF-κB signaling pathway by targeting miR-449a, so as to reduce the inflammatory response to peripheral nerve injury and repair nerve injury.


Asunto(s)
Células Madre Mesenquimatosas , MicroARNs , Traumatismos de los Nervios Periféricos , Animales , Ratas , Citocinas , MicroARNs/genética , FN-kappa B , Inhibidor NF-kappaB alfa , Transducción de Señal , Factor de Necrosis Tumoral alfa
9.
Sci Total Environ ; 850: 158038, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-35981589

RESUMEN

Tens of thousands of species are increasingly confronted with habitat degradation and threatened with local extirpation and global extinction as a result of human activities. Understanding the local processes that shape the regional distribution patterns of at-risk species is useful in safeguarding species against threats. However, there is only limited understanding of the processes that shape the regional distribution patterns of threatened species. We explored the drivers and patterns of species richness of threatened, non-threatened and total terrestrial mammals by employing multi-region multi-species occupancy models based on data from a broad camera trapping survey at 1096 stations stratified across different levels of human activities in 54 mountain forests in southwest China. We compared correlates between total and threatened species richness and examined relationships of human impact variables with the proportion of threatened species and the site's local contribution to ß diversity (LCBD). We found that threatened species richness was negatively related to human modification and human presence. However, both non-threatened and total species richness increased as human modification increased. Predicted proportions of threatened species were strongly and positively related to LCBD but negatively related to human modification and human presence. Our results indicate that human impacts can lead to disproportionate loss of threatened terrestrial mammals and highlight the importance of considering threatened species diversity independently from total species richness for directing conservation resources. Our approach represents one of the highest-resolution analyses of different types of human impacts on regional diversity patterns of threatened terrestrial mammals available to inform conservation policy.


Asunto(s)
Efectos Antropogénicos , Biodiversidad , Especies en Peligro de Extinción , Animales , Conservación de los Recursos Naturales , Ecosistema , Humanos , Mamíferos
10.
ACS Appl Mater Interfaces ; 14(13): 15214-15224, 2022 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-35316015

RESUMEN

Controlling the composition and microstructure of the solid electrolyte interphase (SEI) layer is critical to improving the cycling stability of the high-energy-density lithium-metal electrode. It is a quite tricky task to control the properties of the SEI layer which is conventionally formed by the chemical reactions between a Li metal and the additives. Herein, we develop a new route to synthesize a lithium-compatible sol of the sulfide electrolyte Li3PS4, so that a Li3PS4 artificial SEI layer with a controllable nanoscale thickness and high phase purity can be prepared by spin-coating. The layer stabilizes the lithium/electrolyte interface by homogenizing the Li-ion flux, preventing the parasitic reactions, and alleviating concentration polarization. Consequently, a symmetrical cell with the Li3PS4-modified lithium electrodes can achieve stable lithium plating/stripping for 800 h at a current density of 1 mA cm-2. The Li-S batteries assembled with the Li3PS4-protected Li anodes show better capacity retention than their bare Li counterparts, whose average decay rate from the 240th cycle to the 800th cycle is only 0.004%/cycle. In addition, the Li3PS4 layer improves the rate capacity of the batteries, significantly enhancing the capacity from 175 to 682 mA h g-1 at a 2 C rate. The spin-coated Li3PS4 artificial SEI layer provides a new strategy to develop high-performance Li metal batteries.

11.
Diagnostics (Basel) ; 12(2)2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-35204544

RESUMEN

Interferon-gamma release assays (IGRAs) are widely used in the diagnosis of Mycobacterium tuberculosis (M. tuberculosis) infection by detecting interferon-γ released by previously sensitized T-cells in-vitro. Currently, there are two assays based on either enzyme-linked immunosorbent assay (ELISA) or enzyme-linked immunospot (ELISPOT) technology, with several generations of products available. The diagnostic value of IGRAs in the immunocompromised population is significantly different from that in the immunocompetent population because their results are strongly affected by the host immune function. Both physiological and pathological factors can lead to an immunocompromised situation. We summarized the diagnostic value and clinical recommendations of IGRAs for different immunocompromised populations, including peoplewith physiological factors (pregnant and puerperal women, children, and older people), as well as people with pathological factors (solid organ transplantation recipients, combination with human immunodeficiency virus infection, diabetes mellitus, end-stage renal disease, end-stage liver disease, and chronic immune-mediated inflammatory diseases). Though the performance of IGRAs is not perfect and often requires a combination with other diagnostic strategies, it still has some value in the immunocompromised population. Hopefully, the newly developed IGRAs could better target this population.

12.
Conserv Biol ; 36(3): e13839, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34533235

RESUMEN

In the Anthropocene, understanding the impacts of anthropogenic influence on biodiversity and behavior of vulnerable wildlife communities is increasingly relevant to effective conservation. However, comparative studies aimed at disentangling the concurrent effect of different types of human disturbance on multifaceted biodiversity and on activity patterns of mammals are surprisingly rare. We applied a multiregion community model to separately estimate the effects of cumulative human modification (e.g., settlement, agriculture, and transportation) and human presence (aggregated presence of dogs, people, and livestock) on species richness and functional composition of medium- and large-bodied mammals based on camera trap data collected across 45 subtropical montane forests. We divided the detected mammal species into three trophic guilds-carnivores, herbivores, and omnivores-and assessed the nocturnal shifts of each guild in response to anthropogenic activities. Overall, species richness tended to increase (ß coefficient = 0.954) as human modification increased but richness decreased as human presence increased (ß = -1.054). Human modification was associated with significantly lower functional diversity (mean nearest taxon distance [MNTD], ß = -0.134; standardized effect sizes of MNTD, ß = -0.397), community average body mass (ß = -0.240), and proportion of carnivores (ß = -0.580). Human presence was associated with a strongly reduced proportion of herbivores (ß = -0.522), whereas proportion of omnivores significantly increased as human presence (ß = 0.378) and habitat modification (ß = 0.419) increased. In terms of activity patterns, omnivores (ß = 12.103) and carnivores (ß = 9.368) became more nocturnal in response to human modification. Our results suggest that human modification and human presence have differing effects on mammals and demonstrate that anthropogenic disturbances can lead to drastic loss of functional diversity and result in a shift to nocturnal behavior of mammals. Conservation planning should consider concurrent effects of different types of human disturbance on species richness, functional diversity, and behavior of wildlife communities.


Pérdidas en la Diversidad Funcional y Cambios en el Comportamiento Nocturno de los Mamíferos bajo la Perturbación Antropogénica Resumen En el Antropoceno, el conocimiento sobre la influencia antropogénica sobre la biodiversidad y el comportamiento de las comunidades vulnerables de fauna es cada vez más relevante para la conservación efectiva. Sin embargo, sorprende que los estudios comparativos dirigidos a desentrañar el efecto concurrente de los diferentes tipos de perturbación humana sobre la biodiversidad multifacética y sobre los patrones de actividad de los mamíferos son escasos. Aplicamos un modelo de comunidad multirregional para estimar de manera separada los efectos de la modificación humana (p. ej.: establecimientos, agricultura, transporte) y la presencia humana (presencia agregada de perros, gente y ganado) acumuladas sobre la riqueza de especies y la composición funcional de los mamíferos de tamaño mediano y grande con base en datos de fototrampas recolectados en 45 bosques montanos subtropicales. Dividimos las especies de mamíferos detectadas en tres gremios tróficos: carnívoros, herbívoros y omnívoros, y analizamos los cambios nocturnos de cada gremio como respuesta a las actividades antropogénicas. En general, la riqueza de especies tuvo una tendencia al incremento (coeficiente ß = 0.954) conforme aumentaron las modificaciones humanas, pero la riqueza disminuyó conforme incrementó la presencia humana (ß = −1.054). Las modificaciones humanas estuvieron asociadas con una diversidad funcional (distancia promedio al taxón más cercano [DPTC], ß = −0.134; tamaños del efecto estandarizado de la DPTC, ß = −0.397), masa corporal promedio de la comunidad (ß = −0.240) y proporción de carnívoros (ß = −0.580) significativamente más bajas. La presencia humana estuvo asociada con una proporción gravemente reducida de herbívoros (ß = −0.522), mientras que la proporción de omnívoros incrementó significativamente conforme aumentaron la presencia humana (ß = 0.378) y la modificación del hábitat (ß = 0.419). En cuanto a los patrones de actividad, los omnívoros (ß = 12.103) y los carnívoros (ß = 9.368) se volvieron más nocturnos como respuesta a las modificaciones humanas. Nuestros resultados sugieren que las modificaciones humanas y la presencia de personas tienen efectos diferentes sobre los mamíferos y demuestran que las perturbaciones antropogénicas pueden llevar a pérdidas drásticas de la diversidad funcional y resultar en un cambio hacia el comportamiento nocturno en los mamíferos. La planeación de la conservación debería considerar los efectos concurrentes de los diferentes tipos de perturbaciones humanas sobre la riqueza de especies, la diversidad funcional y el comportamiento de las comunidades faunísticas.


Asunto(s)
Efectos Antropogénicos , Conservación de los Recursos Naturales , Animales , Animales Salvajes , Biodiversidad , Conservación de los Recursos Naturales/métodos , Perros , Ecosistema , Humanos , Mamíferos/fisiología
13.
Zool Res ; 42(4): 389-400, 2021 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-34047079

RESUMEN

The flying squirrels (Pteromyini, Rodentia) are the most diverse and widely distributed group of gliding mammals. Taxonomic boundaries and relationships within flying squirrels remain an area of active research in mammalogy. The discovery of new specimens of Pteromys ( Hylopetes) leonardi Thomas, 1921 previously considered a synonym of Hylopetes alboniger, in Yunnan Province, China allowed a morphological and genetic reassessment of the status of this taxon. Phylogenetic reconstruction was implemented using sequences of two mitochondrial (12S ribosomal DNA and 16S ribosomal DNA) and one nuclear (interphotoreceptor retinoid-binding protein) gene fragments. Morphological assessments involved examinations of features preserved on skins, skulls, and penises of museum specimens, supplemented with principal component analysis of craniometric data. Together these assessments revealed that this taxon should be recognized not only as a distinct species, and should also be placed within a new genus, described here as Priapomys.


Asunto(s)
Sciuridae/clasificación , Animales , China , ADN Mitocondrial/genética , Filogenia , ARN Ribosómico/genética , Sciuridae/anatomía & histología , Sciuridae/genética , Especificidad de la Especie
15.
Neurosci Lett ; 758: 135674, 2021 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-33529652

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative condition leading to severe disability from progressive impairments in cognitive functions including memory and learning. Non-coding microRNAs (miRNAs or miRs) have been linked to the pathogenesis of AD. The present study aimed to investigate the clinical significance and biological function of miR-140 in AD. First, we examined the expression of miR-140 and PINK1 in brain tissues of the established AD model rats and neurons cultured with Aß-derived diffusible ligands (AßDDLs). We identified an interaction between miR-140 and PINK1, and measured spatial learning and memory abilities of the model rats using the Morris water maze (MWM) test. After ectopic expression and depletion experiments in neurons and AD rats, we measured the levels of reactive oxygen species (ROS), and mitochondrial membrane potential (MMP), along with mTOR expression and phosphorylation, and autophagy-related factors. Results showed up-regulation of miR-140 and down-regulation of PINK1 in AD model rats and neurons. PINK1 was verified to be a direct target of miR-140, and silencing of miR-140 suppressed mitochondrial dysfunction, and enhanced autophagy in AD model rats and neurons, as supported by decreased levels of mTOR expression and phosphorylation, ß-amyloid p-Tau (Ser396), p-Tau (Thr231), Tau and ROS, and increased MMP levels and expression of Beclin 1 expression and LC3-II/LC3-I. Collectively, functional suppression of miR-140 enhanced autophagy and prevented mitochondrial dysfunction by upregulating PINK1, ultimately suggesting a novel therapeutic target for AD.


Asunto(s)
Enfermedad de Alzheimer/genética , Hipocampo/patología , MicroARNs/metabolismo , Proteínas Quinasas/genética , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/administración & dosificación , Animales , Autofagia/genética , Células Cultivadas , Modelos Animales de Enfermedad , Silenciador del Gen , Humanos , Masculino , Aprendizaje por Laberinto , Potencial de la Membrana Mitocondrial/genética , MicroARNs/genética , Neuronas/metabolismo , Fragmentos de Péptidos/administración & dosificación , Cultivo Primario de Células , Ratas , Especies Reactivas de Oxígeno/metabolismo , Organismos Libres de Patógenos Específicos
16.
Indian Pediatr ; 57(1): 39-42, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31937696

RESUMEN

OBJECTIVE: To determine the diagnostic accuracy of pneumococcal antigen detection in diagnosis of pneumococcal meningitis in children. METHODS: Purulent meningitis was diagnosed according to European Society for Clinical Microbiology and Infectious Diseases (ESCMID) guideline between July 2014 and June 2016. Along with a cerebrospinal fluid (CSF) culture, pneumococcal antigen detection in cerebrospinal fluid (CSF) was performed, and further identification of pathogens was done with 16S rDNA-PCR and high-throughput sequencing. RESULTS: CSF samples collected from 184 children (median age of 1.92 mo). CSF culture was used as the gold standard. 46 (25%) had positive results for culture and 10 (5.4%) were pneumococci; 34 (18.5%) were pneumococcal antigen positive. The sensitivity and specificity of pneumococcal antigen detection were 100% (95% CI: 89.4%-100%) and 86.2% (95% CI: 96.4%-99.9%), respectively. 92.3% (12/13) were confirmed by nucleic acid detection to be pneumococci. CONCLUSIONS: Pneumococcal antigen detection in CSF has adequate sensitivity and specificity in diagnosing pneumococcal meningitis.


Asunto(s)
Antígenos Bacterianos/líquido cefalorraquídeo , Técnicas Bacteriológicas/métodos , Meningitis Neumocócica/diagnóstico , Adolescente , Niño , Preescolar , Humanos , Inmunoensayo , Lactante , Recién Nacido , Reacción en Cadena de la Polimerasa , Sensibilidad y Especificidad , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/aislamiento & purificación
18.
ACS Appl Mater Interfaces ; 11(47): 44556-44565, 2019 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-31663715

RESUMEN

Lithium-oxygen (Li-O2) batteries have been widely recognized as appealing power systems for their extremely high energy density versus common Li-ion batteries. However, there are still lots of issues that need to be addressed toward the practical application. Here, free-standing Co-doped NiO three-dimensional nanosheets were prepared by a hydrothermal synthesis method and directly employed as the air-breathing cathode of the Li-O2 battery. The morphological phenomenon and electrochemical performance of the as-prepared cathode material were characterized by high-resolution scanning electron microscopy, X-ray diffraction, cyclic voltammetry, galvanostatic charge-discharge tests, and electrochemical impedance spectroscopy measurements. The Co-doped NiO electrode delivered a maximum discharge capacity of around 12 857 mA h g-1 with a low overpotential (0.82 V) at 200 mA g-1. Under upper-limit specific capacities of 500 mA h g-1 at 400 mA g-1, the Li-O2 batteries exhibited a long cycle life of 165 cycles. Compared with the undoped NiO electrode, the Li-O2 battery based on the Co-doped NiO cathode showed significantly higher oxygen reduction reaction and oxygen evolution reaction activities. This superior electrochemical performance is because of the partial substitution of Ni2+ in the NiO matrix by Co2+ to improve the p-type electronic conductivity of NiO. In addition, the morphology and specific surface area of NiO are affected by Co doping, which can expand the electrode-electrolyte contact area and lead to sufficient space for Li2O2 deposition. This approach harnesses the great potential of Co-doped NiO nanosheets for practical applications as advanced electrodes for rechargeable Li-O2 batteries.

19.
Can J Infect Dis Med Microbiol ; 2019: 6456321, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31485283

RESUMEN

BACKGROUND AND OBJECTIVE: Haemophilus influenzae (HI) is a common cause of community-acquired pneumonia in children. In many countries, HI strains are increasingly resistant to ampicillin and other commonly prescribed antibiotics, posing a challenge for effective clinical treatment. This study was undertaken to determine the antibiotic resistance profiles of HI isolates from Chinese children and to provide guidelines for clinical treatment. METHODS: Our Infectious Disease Surveillance of Pediatrics (ISPED) collaboration group includes six children's hospitals in different regions of China. The same protocols and guidelines were used by all collaborators for the culture and identification of HI. The Kirby-Bauer method was used to test antibiotic susceptibility, and a cefinase disc was used to detect ß-lactamase activity. RESULTS: We isolated 2073 HI strains in 2016: 83.9% from the respiratory tract, 11.1% from vaginal secretions, and 0.5% from blood. Patients with respiratory isolates were significantly younger than nonrespiratory patients (P < 0.001). Of all 2073 strains, 50.3% were positive for ß-lactamase and 58.1% were resistant to ampicillin; 9.3% were ß-lactamase-negative and ampicillin-resistant. The resistance rates of the HI isolates to trimethoprim-sulfamethoxazole, azithromycin, cefuroxime, ampicillin-sulbactam, cefotaxime, and meropenem were 71.1%, 32.0%, 31.2%, 17.6%, 5.9%, and 0.2%, respectively. CONCLUSIONS: More than half of the HI strains isolated from Chinese children were resistant to ampicillin, primarily due to the production of ß-lactamase. Cefotaxime and other third-generation cephalosporins could be the first choice for the treatment of ampicillin-resistant HI infections.

20.
Biomed Pharmacother ; 115: 108945, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31100541

RESUMEN

As the primary active component in tobacco, nicotine affects many aspects of human metabolism. Diet and gut microbiota are key factors that profoundly influence human lipid and glucose metabolism. However, the diet-based differential impacts of nicotine on blood lipid and glucose levels as well as on the gut microbiota are still largely unknown. Here we show that 4-week oral administration of nicotine (2 mg/kg) resulted in bodyweight and fat decrease in both normal-chow (NCD)- and high-fat diet (HFD)-fed mice. But nicotine showed little influence on the plasma levels of lipids, glucose and inflammatory cytokines in NCD-fed mice but moderately deteriorated these parameters in HFD-fed ones. 16S sequencing showed that nicotine perturbed bacterial diversity and community composition of gut microbiota more pronouncedly in HFD mice. At genus level, nicotine dramatically increased Ruminococcaceae UCG-009 in HFD condition but not in NCD feeding. Interestingly, co-treatment with antibiotics (ampicillin + norfloxacin) substantially abolished the lipid-enhancing effect of nicotine in HFD-fed mice, suggesting an important role of gut microbes in the lipid-modulatory effect of nicotine. Together, our results indicate that the harmful effects of nicotine on metabolism and systemic inflammation are diet-dependent. Chronic exposure to nicotine may alter the gut microbiota especially in HFD-fed animals.


Asunto(s)
Dieta Alta en Grasa , Microbioma Gastrointestinal/efectos de los fármacos , Lípidos/sangre , Metaboloma/efectos de los fármacos , Nicotina/efectos adversos , Administración Oral , Animales , Antibacterianos/farmacología , Peso Corporal/efectos de los fármacos , Heces/microbiología , Masculino , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Nicotina/administración & dosificación , ARN Ribosómico 16S/genética
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