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Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder characterized primarily by impaired social communication and rigid, repetitive, and stereotyped behaviors. Many studies implicate abnormal synapse development and the resultant abnormalities in synaptic excitatory-inhibitory (E/I) balance may underlie many features of the disease, suggesting aberrant neuronal connections and networks are prone to occur in the developing autistic brain. Astrocytes are crucial for synaptic formation and function, and defects in astrocytic activation and function during a critical developmental period may also contribute to the pathogenesis of ASD. Here, we report that increasing hippocampal astrogenesis during development induces autistic-like behavior in mice and a concurrent decreased E/I ratio in the hippocampus that results from enhanced GABAergic transmission in CA1 pyramidal neurons. Suppressing the aberrantly elevated GABAergic synaptic transmission in hippocampal CA1 area rescues autistic-like behavior and restores the E/I balance. Thus, we provide direct evidence for a developmental role of astrocytes in driving the behavioral phenotypes of ASD, and our results support that targeting the altered GABAergic neurotransmission may represent a promising therapeutic strategy for ASD.
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Transtorno do Espectro Autista , Transtorno Autístico , Animais , Transtorno do Espectro Autista/genética , Hipocampo/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Células Piramidais/fisiologia , Transmissão SinápticaRESUMO
OBJECTIVES: To study the effect of levothyroxine sodium tablets on the growth and development and thyroid function in preterm infants with thyroid dysfunction. METHODS: A retrospective analysis was performed for 82 preterm infants who were born in the Department of Obstetrics of the First People's Hospital of Yunnan Province, from January 1, 2013 to December 31, 2017, and these infants were hospitalized after birth in the Department of Neonatology of the hospital. They were regularly followed up to observe growth and development and thyroid function at the outpatient service of the Department of Neonatology. According to thyroid function test results, they were divided into an abnormal thyroid function group (observation group; n=31) and a normal thyroid function group (control group; n=51). The infants in the observation group were given oral administration of levothyroxine sodium tablets, while those in the control group were not given any treatment. The two groups were compared in terms of the physical and intelligence development and thyroid function of preterm infants with various gestational ages (28-<32 weeks, 32-<34 weeks, and 34-<37 weeks) after regular follow-up to the corrected age of 12 months. RESULTS: There were no significant differences in physical development indices (body length, body weight, and head circumference) between the observation and control groups at various gestational ages after follow-up to the corrected age of 12 months (P>0.05). There were no significant differences between the two groups in the scores of each functional area of the Gesell Developmental Scale among the preterm infants with a gestational age of 28-<32 weeks and 32-<34 weeks after follow-up to the corrected age of 12 months (P>0.05). For the preterm infants with a gestational age of 34-<37 weeks, compared with the control group, the observation group had a significantly lower score of gross motor ability at the age of 3 and 12 months, significantly lower scores of fine motor ability, language ability, and adaptation ability at the age of 12 months (P<0.05), and a significantly lower score of personal-social ability at the age of 3 months (P<0.05). However, the score of personal-social ability in the observation group was not significantly different from the control group at the age of 12 months (P>0.05). After 2-4 weeks of treatment with levothyroxine sodium tablets, the thyroid function of the 31 preterm infants with thyroid dysfunction returned to normal. Among the 31 infants, 21 (68%) achieved complete drug withdrawal, with normal results of neonatal screening (100%); 10 infants (32%) failed to achieve drug withdrawal, and only 2 (20%) out of the 10 infants had normal neonatal screening results (P<0.05). CONCLUSIONS: Early diagnosis and reasonable treatment can reduce the impact on growth and development in preterm infants with thyroid dysfunction. Most preterm infants tend to have transient thyroid dysfunction, while those with positive results of neonatal screening are more likely to develop permanent thyroid dysfunction.
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Preparações Farmacêuticas , Glândula Tireoide , China , Feminino , Seguimentos , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Estudos RetrospectivosRESUMO
Hederagenin is an effective constituent of many medical plants, such as Clematidis Radix, and has a wide range of applications in anti-tumor, anti-inflammatory, antidepressant, hepatoprotective antibacterial, et al. In order to obtain the efficient production of yeast cells for hederagenin,we successfully cloned and screened out a P450 gene MdMA02 from Malus×domestica which can catalyze oleanolic acid C-23 oxidation with our developed plug and play platform. Its amino acid homology is only 32% as compared to characterized CYP72A68v2. By transforming MdMA02 to the oleanolic acid-producing strain BY-OA, a hederagenin-producing strain was constructed and hederagenin's titer could achieve 101 mg·L⻹ using high cell density fermentation, which was 337 times higher than in shake flasks culturing. This study provides a basis for further research on promoting the creation of oleanane-type pentacyclic triterpenoids biosynthetic pathway analysis and relative cell factories construction.
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Ácido Oleanólico/análogos & derivados , Vias Biossintéticas , Contagem de Células , Ácido Oleanólico/metabolismo , Saccharomyces cerevisiaeRESUMO
Nerolidol is an important constituent of terpenoid essential oil and has excellent anti-tumor, anti-bacterial, and anti-oxidative properties. For realizing heterogenous production of nerolidol, our research firstly integrated the codon-optimized Actinidia sinensis nerolidol synthase gene (NES) into the terpenoid chassis strain FPP-001, and obtained NES-001 that could produce 2.71 mgâ¢L⻹ nerolidol. Then, the N-terminal of the NES was fused with FPS by linker peptide GGGS. With this strategy, nerolidol production improved by 59.80-fold, reaching 162.07 mgâ¢L⻹. Finally, by introduction of auxotrophic marker TRP1 in NES-002, the resulting strain NES-003 could produce 1 711.53 mgâ¢L⻹ by high cell density fermentation method. This study provides the basis for the fermentative production of nerolidol and other sesquiterpenoids.
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Saccharomyces cerevisiae/metabolismo , Sesquiterpenos/metabolismo , Fermentação , Microbiologia IndustrialRESUMO
OBJECTIVE: To clone and express recombinant calpain of Schistosoma japonicum (Sjcalpain), observe the distribution of Sjcalpain in S. japonicum cercariae and analyze its role in skin invasion. METHODS: The primers were designed according to the full-length sequence of calpain (GenBank accession No. AB016726). The genes encoding catalytic domain and Ca2+ binding domain of Sjcalpain were amplified by PCR, and the target fragments were subcloned into pET-28a. The recombinant proteins were expressed in E. coli BL21 (DE3) and purified by Ni-NTA resin. The rabbit polyclonal antibodies were prepared with the two purified recombinant proteins by immunizing New Zealand white rabbits. ELISA was used to detect the titer of rabbit antiserum. Immunolocalization was used to investigate the distribution of Sjcalpain in S. japonicum cercariae. Cercariae were incubated with specific inhibitor before infection of mice and the worm reduction rate was calculated. RESULTS: The recombinant expression vector Sjcalpain catalytic domain/pET28a and Sjcalpain Ca2+ binding domain/pET28a were constructed and the recombinant proteins were successfully expressed in E. coli BL21 (DE3) (about M(r) 43 000 and M(r) 39 000, respectively). The two target proteins were expressed as inclusion bodies. The purified target proteins were obtained through Ni-NTA affinity purification. ELISA result showed that the titer of prepared rabbit polyclonal antibodies was higher than 1 : 80 000. Immunolocalization study demonstrated that Sjcalpain protein was mainly expressed in the head of cercariae. Inhibition assays suggested that the average number of adult worms in calpain inhibitor-incubation group and control group was 19 and 23, respectively, with a worm reduction rate of 17.4%. CONCLUSION: Sjcalpain is mainly expressed in the head of S. japonicum cercariae. Inhibition of Sjcalpain could reduce the number of invading cercariae in infected mice, which suggest that Sjcalpain may play a role in skin invasion by cercariae.
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Calpaína/metabolismo , Schistosoma japonicum/metabolismo , Esquistossomose Japônica/metabolismo , Animais , Cercárias , Ensaio de Imunoadsorção Enzimática , Escherichia coli , Camundongos , Coelhos , Proteínas Recombinantes , Schistosoma japonicum/genéticaRESUMO
Multidrug-resistant (MDR) Enterobacteriales infections have become an urgent global threat to public health. The aim of this study was to evaluate the efficacy of zidovudine-amikacin combination therapy in vitro and in vivo. Molecular characteristics and antibiotic resistance profiles of 53 amikacin-resistant MDR, extensively drug-resistant (XDR), or pan-drug-resistant (PDR) clinical isolates were examined via PCR and susceptibility testing. Checkerboard assays were performed for these 53 isolates to assess in vitro synergistic effects of the zidovudine-amikacin combination, and static time-kill experiments were performed for four XDR or PDR Enterobacteriales isolates. A Galleria mellonella model and a rat tissue cage infection model were established to assess in vivo synergistic effects. The aac(6')-Ib gene was detected in 25 (47.2%) isolates, followed by armA in 5 (9.4%) isolates, rmtB in 27 (50.9%) isolates, and rmtC in 3 (5.8%) isolates. Checkerboard assays showed the synergy of this combination against 38 (71.7%) isolates. The time-kill assays further confirmed that zidovudine strongly synergized with amikacin against four XDR or PDR Enterobacteriales isolates. The Galleria mellonella model study showed that the survival benefit of zidovudine-amikacin combination therapy was significantly better than that of monotherapy for those four Enterobacteriales isolates. Furthermore, the rat tissue cage infection model study showed that zidovudine-amikacin combination therapy displayed more potent bactericidal activity than monotherapy after 3 and 7 days of treatment for the above four isolates. Our data support the idea that the zidovudine-amikacin combination could be a plausible alternative therapy against infections with amikacin-resistant MDR Enterobacteriales, especially with XDR and PDR Enterobacteriales. IMPORTANCE Our study revealed for the first time that the zidovudine-amikacin combination shows a significant bactericidal effect against amikacin-resistant MDR, XDR, and PDR Enterobacteriales. Second, using in vitro and in vivo approaches, our study showed that zidovudine strongly synergized with amikacin against amikacin-resistant MDR Enterobacteriales isolates. Most importantly, with regard to survival benefit, pharmacokinetics, and bactericidal effects, our in vivo experiment demonstrated the effectiveness of zidovudine-amikacin.
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Objective: To investigate the correlation between serum parathyroid hormone (PTH) levels and in-hospital major adverse cardiovascular events (MACE) in patients with acute ST-segment elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (PCI), and establish a risk prediction model based on parameters such as PTH for in-hospital MACE. Methods: This observational retrospective study consecutively enrolled 340 patients who underwent primary PCI for STEMI between January 2016 and December 2020, divided into a MACE group (n=92) and a control group (n=248). The least absolute shrinkage and selection operator (LASSO) and logistic regression analyses were used to determine the risk factors for MACE after primary PCI. The rms package in R-studio statistical software was used to construct a nomogram, to detect the line chart C-index, and to draw a calibration curve. The decision curve analysis (DCA) method was used to evaluate the clinical application value and net benefit. Results: Correlation analysis revealed that PTH level positively correlated with the occurrence of in-hospital MACE. Receiver operating characteristic curve analyses revealed that PTH had a good predictive value for in-hospital MACE. Multivariate logistic regression analysis indicated that Killip class II-IV, and FBG were independently associated with in-hospital MACE after primary PCI. A nomogram model was constructed using the above parameters. The model C-index was 0.894 and the calibration curve indicated that the model was well calibrated. The DCA curve suggested that the nomogram model was better than TIMI score model in terms of net clinical benefit. Conclusion: Serum PTH levels in patients with STEMI are associated with in-hospital MACE after primary PCI, and the nomogram risk prediction model based on PTH demonstrated good predictive ability with obvious clinical practical value.
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Although the ecological safety of nanomaterials is of widespread concern, their current ambient concentrations are not yet sufficient to cause serious toxic effects. Thus, the nontoxic bioimpact of nanomaterials in wastewater treatment has attracted increasing attention. In this study, the effect of nano zinc oxide (nZnO), one of the most widely used nanomaterials, on the anaerobic biodegradation of methyl orange (MO) by Shewanella oneidensis MR-1 was comprehensively investigated. High-dosage nZnO (>0.5 mg/L) caused severe toxic stress on S. oneidensis MR-1, resulting in the decrease in decolorization efficiency. However, nZnO at ambient concentrations could act as nanostimulants and promote the anaerobic removal of MO by S. oneidensis MR-1, which should be attributed to the improvement of decolorization efficiency rather than cell proliferation. The dissolved Zn2+ was found to contribute to the bioeffect of nZnO on MO decolorization. Further investigation revealed that low-dosage nZnO could promote the cell viability, membrane permeability, anaerobic metabolism, as well as related gene expression, indicating that nZnO facilitated rather than inhibited the anaerobic wastewater treatment under ambient conditions. Thus, this work provides a new insight into the bioeffect of nZnO in actual environment and facilitates the practical application of nanomaterials as nanostimulants in biological process.
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Shewanella , Óxido de Zinco , Anaerobiose , Biodegradação Ambiental , Shewanella/metabolismo , Óxido de Zinco/metabolismo , Óxido de Zinco/toxicidadeRESUMO
Numerous studies have shown that zinc oxide nanoparticles (nZnO) have an inhibitory effect on wastewater biotreatment, where doses exceeding ambient concentrations are used. However, the effect of ambient concentrations of ZnO (<1 mg/L) on anaerobic digestion processes is not clear. Herein, this study comprehensively explored the impact of nZnO on the denitrification performance and core microbial community of activated sludge under ambient concentrations. Results showed that only 0.075 mg/L nZnO had shown a beneficial effect on nitrogen removal by activated sludge. When nZnO concentration reached 0.75 mg/L, significant enhancement of nitrate reduction and mitigation of nitrite accumulation were observed, indicating a remarkable stimulatory effect on nitrogen removal. Simultaneously, nZnO could weaken the sludge surface charge and improve the secretion of extracellular polymeric substances, thus enhancing sludge flocculation for denitrification. Microbial community analysis revealed that nZnO exposure increased the relative abundance of denitrifying bacteria, which could contribute to the reinforcement of traditional denitrification. Furthermore, exogenous addition of NH4+ significantly inhibited the accumulation of nitrite, implying that nZnO had a potential to improve the denitrification process via a partial denitrification-anammox pathway. Considering current ambient concentration, the stimulatory effect shown in our work may better represent the actual behavior of ZnO in wastewater biotreatment.
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Desnitrificação , Nanopartículas , Oxidação Anaeróbia da Amônia , Reatores Biológicos , Nitrogênio , Oxirredução , Esgotos , Águas ResiduáriasRESUMO
BACKGROUND: Juvenile idiopathic arthritis (JIA) characterized by arthritis of unknown origin is the most common childhood chronic rheumatic disease, caused by both host genetic factors and environmental triggers. Recent evidence has mounted to focus on the intestinal microbiota, a potentially recognized set of environmental triggers affecting JIA development. Here we offer an overview of recently published animal and human studies that support the impact of intestinal microbiota in JIA. DATA SOURCES: We searched PubMed for animal and human studies publications with the search terms "intestinal microbiota or gut microbiota" and "juvenile idiopathic arthritis or juvenile chronic arthritis or juvenile rheumatoid arthritis or childhood rheumatoid arthritis or pediatric rheumatoid arthritis". RESULTS: Several comparative studies have demonstrated that intestinal microbial alterations might be triggers in disease pathogenesis. Alternatively, a slice of studies has suggested environmental triggers in early life might disrupt intestinal microbial colonization, including cesarean section, formula feeding, and antibiotic exposure. Aberrant intestinal microbiota may influence the development of JIA by mediating host immune programming and by altering mucosal permeability. CONCLUSIONS: Specific microbial factors may contribute to the pathogenesis of JIA. Intensive studies, however, are warranted to investigate the causality between intestinal dysbiosis and JIA and the mechanisms behind these epidemiologic relationships. Studies are also needed to design the best interventional administrations to restore balanced intestinal microbial communities.
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Artrite Juvenil/microbiologia , Microbioma Gastrointestinal , Previsões , HumanosRESUMO
Environmental pollution caused by antibiotic resistance genes (ARGs) has attracted wide concerns, and various approaches have been proposed to control ARGs dissemination. TiO2 photoexcitation under UV irradiation has been used for such a purpose. But the actual UV intensity is insufficient to trigger the production of reactive oxygen species (ROS) in the aqueous environment. Thus, it is interesting to know how mild photoexcitation of TiO2 with low-intensity UV affects the horizontal transfer of ARGs. In this work, the impact of TiO2 photoexcitation on the transductant efficiency of constructed filamentous phage gM13 to its host Escherichia coli TG1 was investigated. Although individual treatment with nano-TiO2 and UV irradiation both improved the phage infection, TiO2 photoexcitation exhibited a clear synergistic promotion effect. However, excessive UV irradiation resulted in a decrease in transductant formation, implying severe oxidative damage to the phage and bacterial cells. Extracellular ROS produced by moderate photoexcitation of TiO2 could increase the outer membrane permeability, which facilitated phage infection. The increase in pili synthesis induced by intracellular ROS provided more sites for phage recognition and invasion in the presence of TiO2 photoexcitation, which contributed to the transduction process. Our work provides a novel insight into the impact of TiO2 photoexcitation on ARGs diffusion and is helpful for better understanding non-toxic environmental effect of nanomaterials.
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Bacteriófagos , Antibacterianos/farmacologia , Bacteriófagos/genética , Resistência Microbiana a Medicamentos , Genes Bacterianos , Titânio/farmacologiaRESUMO
Electrochemically active bacteria (EAB) are effective for the bioreduction of nitroaromatic compounds (NACs), but the exact reduction mechanisms are unclear yet. Therefore, 3-nitrobenzenesulfonate (NBS) was used to explore the biodegradation mechanism of NACs by EAB. Results show that NBS could be anaerobically degraded by Shewanella oneidensis MR-1. The generation of aminoaromatic compounds was accompanied with the NBS reduction, indicating that NBS was biodegraded via reductive approach by S. oneidensis MR-1. The impacts of NBS concentration and cell density on the NBS reduction were evaluated. The removal of NBS depends mainly on the transmembrane electron transfer of S. oneidensis MR-1. Impairment of Mtr respiratory pathway was found to mitigate the reduction of NBS, suggesting that the anaerobic biodegradation of NBS occurred extracellularly. Knocking out cymA severely impaired the extracellular reduction ability of S. oneidensis MR-1. However, the phenotype of ΔcymA mutant could be compensated by the exogenous electron mediators, implying the trans-outer membrane diffusion of mediators into the periplasmic space. This work provides a new insight into the anaerobic reduction of aromatic contaminants by EAB.
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Shewanella , Anaerobiose , Transporte de Elétrons , Oxirredução , Permeabilidade , Shewanella/genéticaRESUMO
Recently, paradoxical combinations of colistin with anti-Gram-positive bacterial agents were introduced as a treatment alternative for multidrug-resistant Acinetobacter baumannii (MDRAB) infection. We assessed the therapeutic efficacy of the colistin-linezolid combination regimen in vitro and in a murine model of Acinetobacter baumannii pneumonia. A multidrug-resistant clinical strain (MDRAB31) and an extensively drug-resistant clinical strain (XDRAB78) were used in this study. The survival rates of mice and bacterial counts in lung tissue were used to assess the effects of colistin-linezolid combination. The survival rates of colistin-linezolid combination groups significantly increased compared with colistin groups for MDRAB31 (72% versus 32%, P = 0.03) and for XDRAB78 (92% versus 68%, P = 0.031). The colistin-linezolid combination groups significantly reduced the bacterial counts in lung tissue compared with colistin groups for MDRAB31 and for XDRAB78 (P < 0.05). The colistin-linezolid combination had a bactericidal and synergistic effect compared with colistin alone in time-kill assay and in murine model of pneumonia. Our data demonstrated the synergistic effect of colistin-linezolid combination regimen as a treatment alternative for the severe pulmonary infection caused by MDRAB and XDRAB.
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Infecções por Acinetobacter/tratamento farmacológico , Antituberculosos/uso terapêutico , Colistina/administração & dosagem , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Linezolida/administração & dosagem , Pneumonia Bacteriana/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Acinetobacter baumannii/metabolismo , Animais , Modelos Animais de Doenças , Sinergismo Farmacológico , Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Feminino , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Pneumonia Bacteriana/microbiologia , Fatores de Tempo , Tuberculose Resistente a Múltiplos Medicamentos/microbiologiaRESUMO
The lateral parabrachial nucleus (LPBN) is known to relay noxious information to the amygdala for processing affective responses. However, it is unclear whether the LPBN actively processes neuropathic pain characterized by persistent hyperalgesia with aversive emotional responses. Here we report that neuropathic pain-like hypersensitivity induced by common peroneal nerve (CPN) ligation increases nociceptive stimulation-induced responses in glutamatergic LPBN neurons. Optogenetic activation of GABAergic LPBN neurons does not affect basal nociception, but alleviates neuropathic pain-like behavior. Optogenetic activation of glutamatergic or inhibition of GABAergic LPBN neurons induces neuropathic pain-like behavior in naïve mice. Inhibition of glutamatergic LPBN neurons alleviates both basal nociception and neuropathic pain-like hypersensitivity. Repetitive pharmacogenetic activation of glutamatergic or GABAergic LPBN neurons respectively mimics or prevents the development of CPN ligation-induced neuropathic pain-like hypersensitivity. These findings indicate that a delicate balance between excitatory and inhibitory LPBN neuronal activity governs the development and maintenance of neuropathic pain.
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Hiperalgesia/fisiopatologia , Neuralgia/fisiopatologia , Neurônios/metabolismo , Nociceptividade/fisiologia , Núcleos Parabraquiais/fisiologia , Animais , Modelos Animais de Doenças , Agonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Agonistas GABAérgicos/farmacologia , Ácido Glutâmico/metabolismo , Humanos , Hiperalgesia/etiologia , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/fisiologia , Masculino , Camundongos , Camundongos Transgênicos , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Neuralgia/etiologia , Neurônios/efeitos dos fármacos , Optogenética , Núcleos Parabraquiais/citologia , Núcleos Parabraquiais/efeitos dos fármacos , Nervo Fibular/lesões , Nervo Fibular/fisiopatologia , Técnicas Estereotáxicas , Ácido gama-Aminobutírico/metabolismoRESUMO
OBJECTIVE: To investigate the effects of CO(2) pneumoperitoneum on blood flow volume of abdominal organs of rabbits with controlled hemorrhagic shock model and liver impact injuries. METHODS: After controlled hemorrhagic shock and liver impact injuries, the rabbit model was established. Eighteen rabbits subjected to hemorrhagic shock and liver impact injuries were divided into 3 groups randomly according to the volume of lost blood: light hemorrhagic shock (blood loss volume was 10%, 6 ml/kg), moderate hemorrhagic shock (20%, 12 ml/kg) and severe hemorrhagic shock (40%, 22 ml/kg). Intraabdominal pressures of CO(2) pneumoperitoneum was 10 mmHg. Color-labeled microspheres were used to measure the blood flow volume of the liver, kidney and stomach before pneumoperitoneum at 30 minutes and 2 hours after pneumoperitoneum and 30 minutes after deflation. And the mortality and hepatic traumatic condition of rabbits were recorded. RESULTS: Of the 18 rabbits, there were 9 with liver impact injuries at Grade I , 8 at Grade II and 1 at Grade III (according to AIS-2005). The mortality rate in light hemorrhagic shock group was 33.33%, and that in moderate or severe hemorrhagic shock group was 100% within 30 minutes and 2 hours after pneumoperitoneum, respectively. The blood flow volume in the organs detected decreased at 30 minutes under pneumoperitoneum in light and moderate hemorrhagic shock groups. At the same time, the blood flow volume of the liver in moderate hemorrhagic shock group decreased more significantly than that in light hemorrhagic shock group. CONCLUSIONS: The blood flow volume of abdominal organs in rabbits is decreased obviously under CO(2) pneumoperitoneum, with fairly high mortality rate. It is believed that CO(2) pneumoperitoneum should cautiously be used in abdominal injury accompanied with hemorrhagic shock, especially under non-resuscitation conditions.
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Traumatismos Abdominais/diagnóstico , Volume Sanguíneo , Fígado/lesões , Pneumoperitônio Artificial , Choque Hemorrágico/fisiopatologia , Animais , Dióxido de Carbono , Feminino , Masculino , Coelhos , Fluxo Sanguíneo RegionalRESUMO
Coronary artery disease (CAD) is a leading cause of death, and microRNAs (miRNAs) are widely involved in physiological and pathological processes of CAD. We chose the targetscore method calculated via the variational Bayesian Gaussian mixture model (VB-GMM) as the prediction method of target genes. By observing the density overlap, we selected the thresholds of miRNA-1 and miRNA-155. In total, 18 target genes of miRNA-1, and 19 target genes of miRNA-155 were identified. The threshold of miRNA-146a was selected using the |logFC| value, and 16 target genes were screened out. In this study, our major contribution was to predict the target messenger RNAs (mRNAs) of the chosen miRNAs with the gene expression profiles, which can effectively reduce the workload of screening. Although the validated genes constituted only a small part in the final prediction results, it is a good sign for research in the future. It means that we could provide new research aims for future studies focusing on miRNA regulatory mechanisms.
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Photocatalytic catalysis is widely used for pollutant degradation. Since some pollutants with oxidative nature are readily reduced rather than oxidized and reductive reaction caused by photogenerated electrons is limited in the presence of oxygen, photocatalytic reduction process is more applicable for the degradation of pollutants with oxidative nature than oxidation. In this work, a novel bio-photoelectric reductive degradation system (BPRDS), composed of an electrochemically active bacterium Shewanella oneidensis MR-1 and a visible-light photocatalyst Ag3PO4, was established under anaerobic conditions and its photodegradation performance was evaluated through degrading rhodamine B (RhB), a typical organic pollutant. The as-synthesized Ag3PO4 nanoparticles exhibited absorption in the entire visible spectral range of 400-800â¯nm. RhB could be degraded in BPRDS with visible light irradiation under anaerobic conditions, but not be decomposed in the absence of Shewanella cells. Block of Mtr respiratory pathway, a transmembrane electron transport chain, resulted in a reduction in degradation rate of RHB in BPRDS. Dose of riboflavin also substantially decreased the RhB degradation. These results suggest that the electrons released by Shewanella were involved in the RhB photodegradation, which was achieved via a stepwise N-deethylation process. In BPRDS, RhB was degraded by photoreduction, rather than photooxidation. This work is useful to develop integrated physico-chemical-microbial systems for pollutant degradation, facilitate better understanding about the biophotoelectric reductive degradation mechanisms and beneficial to their applications for environmental remediation.
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Fosfatos/química , Rodaminas/metabolismo , Shewanella/metabolismo , Compostos de Prata/química , Catálise , Luz , Oxirredução , Fosfatos/efeitos da radiação , Fotólise , Compostos de Prata/efeitos da radiaçãoRESUMO
The poor survival of mesenchymal stem cells (MSCs) compromises the efficacy of stem cell therapy. Growth factor deprivation is one of the important factors that have challenged the survival of donor MSCs in cell therapy. In this study, the aim was to evaluate the effect of serum deprivation on the cell death of MSCs and to investigate the underlying mechanisms. Apoptosis of MSCs was evaluated with Hoechst 33342/PI staining. Signaling pathways involved in serum-deprivation induced apoptosis were analyzed using Western blotting. The results revealed that serum deprivation induced apoptosis in MSCs within 72 h of treatment. Serum deprivation was shown to lead to protein expression alterations in Bax, Bcl-2, casepase-3, casepase-8, GRP78, and CHOP during experiments. The data suggested that the mitochondria death pathway, the extrinsic apoptotic pathway and the endoplastic reticulum(ER) stress pathway were all involved in MSCs apoptosis. The increase in expression of CHOP and the simultaneous decrease in Bcl-2 expression suggest a synergistic effect in apoptosis induction in both the mitochondrion and the ER.
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Apoptose , Estresse do Retículo Endoplasmático , Células-Tronco Mesenquimais/patologia , Mitocôndrias/patologia , Animais , Proliferação de Células , Forma Celular , Sobrevivência Celular , Células Cultivadas , Meios de Cultura Livres de Soro , Células-Tronco Mesenquimais/metabolismo , Ratos WistarRESUMO
The overuse of antibiotics has resulted in contamination of antibiotics and genes encoding multidrug resistance in some water sources in China. Antibiotics and the antibiotic resistance genes may cause severe hazards to human health via drinking water. Cultivable bacteria in one of the water supply systems in Shanghai were isolated and identified. The multidrug resistance in drinking water for cultivable bacteria and their change and mechanism in water supply system was analyzed using ampicillin (Amp), kanamycin (Kan), rifampicin (Rif), chloramphenicol (Cm) and streptomycin (Str). The results showed that, the isolated microorganisms mainly belonged to 16 genera. Bacillus sp., Arcicella rosea sp. and Sphingomonas sp. existed in the whole process. The multidrug resistances of these three bacteria were enhanced after flowing carbon filtration and water distribution system. Bacillus sp. showed the strongest antibiotic resistance. Real-time PCR was used to quantitatively evaluate the concentration of three integrons and 9 transposons in the water supply system. The results showed that, after BAC filtration and water distribution system, the absolute concentrations of mobile genetic elements increased obviously, which meant that BAC filtration and water distribution system played an important role in influencing antibiotic resistance in the water treatment process.
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Bactérias/efeitos dos fármacos , Água Potável/microbiologia , Farmacorresistência Bacteriana Múltipla , Purificação da Água , Antibacterianos , Bactérias/classificação , China , Testes de Sensibilidade MicrobianaRESUMO
OBJECTIVE: To explore the effects of impact injury of liver on myocardial systolic function and arterial blood gases in rabbits. METHODS: A model of hepatic impact injury was reproduced in rabbits by hitting the xiphoid area with two falling steel balls. Myocardial systolic function and arterial blood gases were measured respectively before injury, immediately and 0.5, 1, 2 hours after injury, and before the death. RESULTS: After injury, heart rate (HR), left ventricular systolic pressure (LVSP), the maximum change rate of left ventricular pressure rise and fall (+/-dp/dt max) descended significantly, while left ventricular end-diastolic pressure (LVEDP) showed no statistically significant change. At the same time, blood pH and HCO(3)(-) fell gradually, and negative base excess (BEecf) showed a significant increase, indicating metabolic acidosis gradually developed. There was no obvious significant difference in partial pressure of carbon dioxide in artery (PaCO(2)) between the values before and after injury. Partial pressure of oxygen in artery (PaO(2)) decreased gradually, but no significant differences were found between the values of 0.5 hour and 1 hour after injury and that before injury. CONCLUSION: After hepatic impact injury, myocardial systolic function deteriorates, metabolic acidosis appears.