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1.
Opt Lett ; 46(22): 5529-5532, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34780405

RESUMO

Twin-field quantum key distribution (TFQKD), using single-photon-type interference, offers a way to exceed the rate-distance limit without quantum repeaters. However, it still suffers from photon losses and dark counts, which impose an ultimate limit on its transmission distance. In this Letter, we propose a scheme to implement TFQKD with an entangled coherent state source in the middle to increase its range, as well as comparing its performance under coherent attacks with that of TFQKD variants. Simulations show that our protocol has a theoretical distance advantage of 400 km. Moreover, the scheme has great robustness against the misalignment error and finite-size effects. Our work is a promising step toward long-distance secure communication and is greatly compatible with future global quantum networks.

2.
J Thorac Dis ; 13(10): 5933-5941, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34795941

RESUMO

Background: Identifying the distribution of pulmonary veins with three-dimensional reconstruction images is of great significance for surgical guidance. Existing models neglect the consistency of the bilateral superior pulmonary veins (SPVs) and lack a simple unified classification pattern. This study aimed to analyze the distributional features of bilateral SPVs, based on a cohort of patients undergoing CT examination. Methods: The three-dimensional computed tomography bronchography and angiography (3D-CTBA) images of 1,520 cases were retrospectively analyzed. The reconstructed images of the right upper lobes were read in 715 cases, and left upper lobes in 805 cases. Through symmetrical analysis, the circulation of main venous branches and the spatial relationships of confluences with adjacent bronchus were compared. Results: The SPVs of bilateral upper lobes showed common distributional features and were divided into three main types. The central vein type, the semi-central vein type, and the non-central vein type accounted for 83.35% [596], 7.84% [56], 8.11% [58] of the 715 cases with right scanning, and 25.71% [207], 62.61% [504], 10.81% [87] of the 805 cases with left scanning, respectively. There were 5 (0.70%) cases with rare variations in the right upper lobe and 7 (0.87%) in the left upper lobe. The attribution of intersubsegmental vein in the posterior segment (V2b) and its position relative to the anterior segmental bronchus (B3) was the basis of classification in the right upper lobe, and the attribution of intersubsegmental vein in the apicoposterior segment (V1+2c) and its position relative to B3 was the basis of classification in the left upper lobe. In this classification system, the branching pattern of the intersegmental vein between the apical segment and the anterior segment (V1b) in the right upper lobe, and the intersegmental vein between the apicoposterior segment and the anterior segment (V1+ 2a) in the left upper lobe were used for subdivision. Conclusions: Our modified system had a high degree of consistency in classifying SPVs in bilateral upper lobes, thus providing guidance for preoperative and intraoperative procedures.

3.
Opt Express ; 29(17): 27661-27673, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34615178

RESUMO

Quantum digital signatures (QDSs) promise information-theoretic security against repudiation and forgery of messages. Compared with currently existing three-party QDS protocols, multiparty protocols have unique advantages in the practical case of more than two receivers when sending a mass message. However, complex security analysis, numerous quantum channels and low data utilization efficiency make it intractable to expand three-party to multiparty scenario. Here, based on six-state non-orthogonal encoding protocol, we propose an effective multiparty QDS framework to overcome these difficulties. The number of quantum channels in our protocol only linearly depends on the number of users. The post-matching method is introduced to enhance data utilization efficiency and make it linearly scale with the probability of detection events even for five-party scenario. Our work compensates for the absence of practical multiparty protocols, which paves the way for future QDS networks.

4.
Opt Express ; 29(20): 32244-32255, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615300

RESUMO

Quantum secret sharing (QSS) is an essential primitive for the future quantum internet, which promises secure multiparty communication. However, developing a large-scale QSS network is a huge challenge due to the channel loss and the requirement of multiphoton interference or high-fidelity multipartite entanglement distribution. Here, we propose a three-user QSS protocol without monitoring signal disturbance, which is capable of ensuring the unconditional security. The final key rate of our protocol can be demonstrated to break the Pirandola-Laurenza-Ottaviani-Banchi bound of quantum channel and its simulated transmission distance can approach over 600 km using current techniques. Our results pave the way to realizing high-rate and large-scale QSS networks.

5.
Inorg Chem ; 60(20): 15627-15634, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34613720

RESUMO

Spurred by the rapid growth of Ru-based complexes as molecular water oxidation catalysts (WOCs), we propose novel ruthenium(II) complexes bearing pyridylpyrrole-carboxylate (H2ppc) ligands as members of the WOC family. The structure of these complexes has 4-picoline (pic)/dimethyl sulfoxide (DMSO) in [Ru(ppc)(pic)2(dmso)] and pic/pic in [Ru(ppc)(pic)3] as axial ligands. Another ppc2- ligand and one pic ligand are located at the equatorial positions. [Ru(ppc)(pic)2(dmso)] behaves as a WOC as determined by electrochemical measurement and has an ultrahigh electrocatalytic current density of 8.17 mA cm-2 at 1.55 V (vs NHE) with a low onset potential of 0.352 V (vs NHE), a turnover number of 241, a turnover frequency of 203.39 s-1, and kcat of 16.34 s-1 under neutral conditions. The H2O/pic exchange of the complexes accompanied by oxidation of a ruthenium center is the initial step in the catalytic cycle. The cyclic voltametric measurements of [Ru(ppc)(pic)2(dmso)] at various scan rates, Pourbaix diagrams (plots of E vs pH), and kinetic studies suggested a water nucleophilic attack mechanism. HPO42- in a phosphate buffer solution is invoked in water oxidation as the proton acceptor.

6.
Eur J Radiol ; 144: 109997, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34634534

RESUMO

PURPOSE: To determine chest CT changes 6 months and 12 months after the onset of coronavirus disease 2019 (COVID-19) in patients with diabetes or hyperglycemia and the risk factors for these residual lung abnormalities. METHODS: In total, 141 COVID-19 patients were assigned to group 1 (diabetes), group 2 (secondary hyperglycemia) or group 3 (controls). Initial and six- and twelve-month follow-up computed tomography (CT) scans were performed 16 days, 175 days and 351 days after symptom onset, respectively. CT findings and clinical and peak laboratory parameters were collected and compared. Univariable and multivariable logistic regression analyses were performed to identify the independent predictors for the presence of residual lung abnormalities at the 6-month follow-up exam. Seven variables (age; the presence of acute respiratory distress syndrome; the duration of hospitalization; the peak levels of lactate dehydrogenase (LDH) and C-reactive protein; and the initial total CT score) were chosen in the final multivariable models. RESULTS: At the six-month follow-up, abnormalities were still observed on chest CT in 77/141 (54.6%) patients. Reticular patterns (40/141, 28.4%) and ground-glass opacities (GGOs) (29/141, 20.6%) were the most common CT abnormalities on the follow-up CT scans. Patients in Groups 1 and 2 had significantly higher incidences of residual lung abnormalities than those in Group 3 (65.4% and 58.3%, respectively vs. 36.6%; p < 0.05). Twelve months after disease onset, the chest CT changes persisted in 13/25 (52.0%) patients. A duration of hospitalization > 20 days (OR: 5.630, 95% CI: 1.394-22.744, p = 0.015), an LDH level ≥ 317 U/L (OR: 7.020, 95% CI: 1.032-47.743, p = 0.046) and a total CT score > 15 (OR: 9.919, 95% CI: 1.378-71.415, p = 0.023) were independent predictors of residual pulmonary abnormalities in patients with diabetes or secondary hyperglycemia. CONCLUSIONS: A considerable proportion of surviving COVID-19 patients with diabetes or secondary hyperglycemia had residual pulmonary abnormalities six months after disease onset, and we found evidence of persistent chest CT changes at the one-year follow-up. Residual lung abnormalities were associated with longer hospital stays, higher peak LDH levels and higher initial total CT scores.

7.
Oncol Lett ; 22(4): 720, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34429760

RESUMO

Epithelial ovarian cancer has the highest mortality rate of all malignant ovarian cancer types. Great progress has been made in the treatment of ovarian cancer in recent years. However, drug resistance has led to a low level of 5-year survival rate of epithelial ovarian cancer, and the molecular mechanism of which remains unknown. The aim of the present study was to identify the role of redox status in the cisplatin (CDDP) resistance of ovarian cancer. CDDP-resistant SK-OV3 (SK-OV3/cddp) cells were prepared and their reactive oxygen species and glutathione levels were investigated. The effects of hydrogen peroxide on the CDDP sensitivity of the SK-OV3/cddp cells and their expression levels of the redox-associated protein growth arrest and DNA damage 45a (GADD45α) were also investigated. In addition, the impact of GADD45α overexpression on cell viability was evaluated in vitro and in vivo, and the levels of Ser-139 phosphorylated H2A histone family member X (γ-H2AX), which is associated with DNA damage, were detected. The results suggested that redox status affected the drug resistance of the ovarian cancer cells by increasing the expression of GADD45α. The overexpression of GADD45α reversed the CDDP resistance of the SK-OV3/cddp cells and increased the level of γ-H2AX. In conclusion, GADD45α alleviated the CDDP resistance of SK-OV3/cddp cells via the induction of redox-mediated DNA damage.

8.
Front Cell Neurosci ; 15: 704334, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34408630

RESUMO

Endoplasmic reticulum (ER) is the main organelle for protein synthesis, trafficking and maintaining intracellular Ca2+ homeostasis. The stress response of ER results from the disruption of ER homeostasis in neurological disorders. Among these disorders, cerebral ischemia is a prevalent reason of death and disability in the world. ER stress stemed from ischemic injury initiates unfolded protein response (UPR) regarded as a protection mechanism. Important, disruption of Ca2+ homeostasis resulted from cytosolic Ca2+ overload and depletion of Ca2+ in the lumen of the ER could be a trigger of ER stress and the misfolded protein synthesis. Brain cells including neurons, glial cells and endothelial cells are involved in the complex pathophysiology of ischemic stroke. This is generally important for protein underfolding, but even more for cytosolic Ca2+ overload. Mild ER stress promotes cells to break away from danger signals and enter the adaptive procedure with the activation of pro-survival mechanism to rescue ischemic injury, while chronic ER stress generally serves as a detrimental role on nerve cells via triggering diverse pro-apoptotic mechanism. What's more, the determination of some proteins in UPR during cerebral ischemia to cell fate may have two diametrically opposed results which involves in a specialized set of inflammatory and apoptotic signaling pathways. A reasonable understanding and exploration of the underlying molecular mechanism related to ER stress and cerebral ischemia is a prerequisite for a major breakthrough in stroke treatment in the future. This review focuses on recent findings of the ER stress as well as the progress research of mechanism in ischemic stroke prognosis provide a new treatment idea for recovery of cerebral ischemia.

9.
Biosci Rep ; 41(8)2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34339487

RESUMO

miR-219-5p has been reported to act as either a tumor suppressor or a tumor promoter in different cancers by targeting different genes. In the present study, we demonstrated that miR-219-5p negatively regulated the expression of TBXT, a known epithelial-mesenchymal transition (EMT) inducer, by directly binding to TBXT 3'-untranslated region. As a result of its inhibition on TBXT expression, miR-219-5p suppressed EMT and cell migration and invasion in breast cancer cells. The re-introduction of TBXT in miR-219-5p overexpressing cells decreased the inhibitory effects of miR-219 on EMT and cell migration and invasion. Moreover, miR-219-5p decreased breast cancer stem cell (CSC) marker genes expression and reduced the mammosphere forming capability of cells. Overall, our study highlighted that TBXT is a novel target of miR-219-5p. By suppressing TBXT, miR-219-5p plays an important role in EMT and cell migration and invasion of breast cancer cells.

10.
Diabetes Res Clin Pract ; 178: 108952, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34273454

RESUMO

AIMS: To investigate the association between glycated hemoglobin (HbA1c) and myocardial dysfunction and to determine whether its association is independent of myocardial perfusion. METHODS: Sixty-four patients with type 2 diabetes mellitus (T2DM) were recruited. They were divided into groups according to their HbA1c level: the controlled T2DM group (HbA1c < 7%) and uncontrolled T2DM groups (HbA1c ≥ 7%). Meanwhile, 30 age-matched healthy volunteers were included. All patients with T2DM and healthy controls underwent cardiovascular magnetic resonance imaging to evaluate the myocardial mechanics and perfusion parameters. RESULTS: The circumferential and longitudinal peak strain (PS) (p = 0.009 and 0.002 respectively) and global radial, circumferential, and longitudinal peak strain diastolic strain rates (PDSRs) (p = 0.002, 0.001, and 0.001 respectively) were lower in the uncontrolled T2DM group than in the controls without diabetes. In multivariable linear regression analysis, HbA1c was independently related to all directions of the PS and PDSR. The myocardial perfusion parameters were not independently associated with the PS or PDSR. CONCLUSIONS: Cardiac function is impaired in Chinese T2DM patients with poor glucose control (HbA1c ≥ 7%), with preserved left ventricular (LV) ejection fraction, and disease duration <10 years. Poor blood glucose control is an independent predictor of LV myocardial dysfunction for patients with short-term T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Disfunção Ventricular Esquerda , Estudos de Casos e Controles , Hemoglobina A Glicada , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda
11.
Eur J Radiol ; 141: 109810, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34102564

RESUMO

OBJECTIVE: To investigate whether 3D convolutional neural network (CNN) is able to enhance the classification performance of radiologists in classifying pulmonary non-solid nodules (NSNs). MATERIALS AND METHODS: Data of patients with solitary NSNs and diagnosed as adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), or invasive adenocarcinoma (IAC) in pathological after surgical resection were analyzed retrospectively. Ultimately, 532 patients in our institution were included in the study: 427 cases (144 AIS, 167 MIA, 116 IAC) were assigned to training dataset and 105 cases (36 AIS, 41 MIA and 28 IAC) were assigned to validation dataset. For external validation, 177 patients (60 AIS, 69 MIA and 48 IAC) from another hospital were assigned to testing dataset. The clinical and morphological characteristics of NSNs were established as radiologists' model. The trained classification model based on 3D CNN was used to identify NSNs types automatically. The evaluation and comparison on classification performance of the two models and CNN + radiologists' model were performed via receiver operating curve (ROC) analysis and integrated discrimination improvement (IDI) index. The Akaike information criterion (AIC) was calculated to find the best-fit model. RESULTS: In external testing dataset, radiologists' model showed inferior classification performance than CNN model both in discriminating AIS from MIA-IAC and AIS-MIA from IAC (the area under the ROC curve (Az value), 0.693 vs 0.820, P = 0.011; 0.746 vs 0.833, P = 0.026, respectively). However, combining CNN significantly enhanced the classification performance of radiologists and exhibited higher Az values than CNN model alone (Az values, 0.893 vs 0.820, P < 0.001; 0.906 vs 0.833, P < 0.001, respectively). The IDI index further confirmed CNN's contribution to radiologists in classifying NSNs (IDI = 25.8 % (18.3-46.1 %), P < 0.001; IDI = 30.1 % (26.1-45.2 %), P < 0.001, respectively). The CNN + radiologists' model also provided the best fit over radiologists' model and CNN model alone (AIC value 63.3 % vs. 29.5 %, 49.5 %, P < 0.001; 69.2 % vs. 34.9 %, 53.6 %, P < 0.001, respectively). CONCLUSION: CNN successfully classified NSNs based on CT images and its classification performance were superior to radiologists' model. But the classification performance of radiologists can be significantly enhanced when combined with CNN in classifying NSNs.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Invasividade Neoplásica , Redes Neurais de Computação , Radiologistas , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
12.
Opt Lett ; 46(11): 2609, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34061068

RESUMO

In this Erratum the funding and references sections of Opt. Lett.46, 1632 (2021)OPLEDP0146-959210.1364/OL.417851 have been updated.

13.
J Mol Neurosci ; 71(10): 2035-2052, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33970426

RESUMO

White matter damage is a component of most human stroke and usually accounts for at least half of the lesion volume. Subcortical white matter stroke (WMS) accounts for 25% of all strokes and causes severe motor and cognitive dysfunction. The adult brain has a very limited ability to repair white matter damage. Pathological analysis shows that demyelination or myelin loss is the main feature of white matter injury and plays an important role in long-term sensorimotor and cognitive dysfunction. This suggests that demyelination is a major therapeutic target for ischemic stroke injury. An acute inflammatory reaction is triggered by brain ischemia, which is accompanied by cytokine production. The production of cytokines is an important factor affecting demyelination and myelin regeneration. Different cytokines have different effects on myelin damage and myelin regeneration. Exploring the role of cytokines in demyelination and remyelination after stroke and the underlying molecular mechanisms of demyelination and myelin regeneration after ischemic injury is very important for the development of rehabilitation treatment strategies. This review focuses on recent findings on the effects of cytokines on myelin damage and remyelination as well as the progress of research on the role of cytokines in ischemic stroke prognosis to provide a new treatment approach for amelioration of white matter damage after stroke.

14.
Behav Brain Res ; 410: 113357, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-33989729

RESUMO

Post-stroke cognitive impairment (PSCI) is one of the most common complications of stroke, it is also an important reason for the poor prognosis in stroke patients with motor and speech dysfunction. Enriched Environment (EE), a novel and easy-to-implement rehabilitation treatment strategy, is thought to be a potential intervention for PSCI recently. In this paper, we review the therapeutic effects and related mechanisms of EE in PSCI from the level of animal research and clinical application. Besides, we further discuss the application prospects and limitations of EE in PSCI patients.

15.
Opt Express ; 29(7): 10162-10171, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33820149

RESUMO

Quantum digital signatures (QDS) exploit quantum laws to guarantee non-repudiation, unforgeability and transferability of messages with information-theoretic security. Current QDS protocols face two major restrictions, including the requirement of the symmetrization step with additional secure classical channels and the quadratic scaling of the signature rate with the probability of detection events. Here, we present an efficient QDS protocol to overcome these issues by utilizing the classical post-processing operation called post-matching method. Our protocol does not need the symmetrization step, and the signature rate scales linearly with the probability of detection events. Simulation results show that the signature rate is three orders of magnitude higher than the original protocol in a 100-km-long fiber. This protocol is compatible with existing quantum communication infrastructure, therefore we anticipate that it will play a significant role in providing digital signatures with unconditional security.

16.
Opt Lett ; 46(7): 1632-1635, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33793504

RESUMO

Device-independent quantum key distribution (DIQKD) exploits the violation of a Bell inequality to extract secure keys even if users' devices are untrusted. Currently, all DIQKD protocols suffer from the secret key capacity bound, i.e., the secret key rate scales linearly with the transmittance of two users. Here we propose a heralded DIQKD scheme based on entangled coherent states to improve entangling rates whereby long-distance entanglement is created by single-photon-type interference. The secret key rate of our scheme can significantly outperform the traditional two-photon-type Bell-state measurement scheme and, importantly, surpass the above capacity bound. Our protocol therefore is an important step towards a realization of DIQKD and can be a promising candidate scheme for entanglement swapping in the future quantum internet.

17.
Lung Cancer ; 155: 78-86, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33761380

RESUMO

PURPOSE: To propose a practical strategy for the clinical application of deep learning algorithm, i.e., Hierarchical-Ordered Network-ORiented Strategy (HONORS), and a new approach to pulmonary nodule classification in various clinical scenarios, i.e., Filter-Guided Pyramid NETwork (FGP-NET). MATERIALS AND METHODS: We developed and validated FGP-NET on a collection of 2106 pulmonary nodules on computed tomography images which combined screened and clinically detected nodules, and performed external test (n = 341). The area under the curves (AUCs) of FGP-NET were assessed. A comparison study with a group of 126 skilled radiologists was conducted. On top of FGP-NET, we built up our HONORS which was composed of two solutions. In the Human Free Solution, we used the high sensitivity operating point for screened nodules, but the high specificity operating point for clinically detected nodules. In the Human-Machine Coupling Solution, we used the Youden point. RESULTS: FGP-NET achieved AUCs of 0.969 and 0.847 for internal and external test. The AUCs of the subsets of the external test set ranged from 0.890 to 0.942. The average sensitivity and specificity of the 126 radiologists were 72.2 ±â€¯15.1 % and 71.7 ±â€¯15.5 %, respectively, while a higher sensitivity (93.3 %) but a relatively inferior specificity (64.0 %) were achieved by FGP-NET. HONORS-guided FGP-NET identified benign nodules with high sensitivity (sensitivity,95.5 %; specificity, 72.5 %) in the screened nodules, and identified malignant nodules with high specificity (sensitivity, 31.0 %; specificity, 97.5 %) in the clinically detected nodules. These nodules could be reliably diagnosed without any intervention from radiologists, via the Human Free Solution. The remaining ambiguous nodules were diagnosed with high performance, which however required manual confirmation by radiologists, via the Human-Machine Coupling Solution. CONCLUSIONS: FGP-NET performed comparably to skilled radiologists in terms of diagnosing pulmonary nodules. HONORS, due to its high performance, might reliably contribute a second opinion, aiding in optimizing the clinical workflow.


Assuntos
Aprendizado Profundo , Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Nódulo Pulmonar Solitário , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Estudos Retrospectivos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X
18.
Mar Drugs ; 19(3)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673526

RESUMO

Two cembranoids, including a new compound, lobocrassin I (1), as well as a known analogue, lobohedleolide (2), were obtained by solvent extraction from octocoral Lobophytum crassum. This study employed a spectroscopic approach to establish the structures of these two cembranoids, and utilized single-crystal X-ray diffraction analysis to determine their absolute configurations. The results of biological activity assays demonstrated that cembranoid 2 exhibited bioactivity against the protein expressions of inducible nitric oxide synthase (iNOS) lipopolysaccharide (LPS)-treated RAW 264.7 mouse macrophage cells.


Assuntos
Antozoários/química , Anti-Inflamatórios/isolamento & purificação , Diterpenos/isolamento & purificação , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Diterpenos/química , Diterpenos/farmacologia , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo II/genética , Células RAW 264.7 , Difração de Raios X
19.
Anim Biotechnol ; : 1-11, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33530818

RESUMO

This study aimed to investigate the effects of active dry yeast (ADY) on growth performance, rumen microbial composition and carcass performance of beef cattle. Thirty-two finishing beef cattle (yak ♂ × cattle-yaks ♀), with an average body weight of 110 ± 12.85 kg, were randomly assigned to one of four treatments: the low plane of nutrition group (control), low plane of nutrition group + ADY 2 g/head daily (ADY2), low plane of nutrition group + ADY 4 g/head daily (ADY4) and the high plane of nutrition group (HPN). Supplementation of ADY increased average daily gain compared to the control group. The neutral detergent fiber and acid detergent fiber apparent digestibility in HPN group was greater than that in control group. The propionic acid concentration in the rumen in ADY2, ADY4, and HPN groups was greater than that in control group. The Simpson and Shannon indexes in control and HPN groups were higher than that in ADY4 group. At the phylum level, the relative abundance of Firmicutes in the HPN group was higher than that in ADY4 group. The relative abundance of Ruminococcaceae UCG-002 in ADY4 group was higher than that in control and HPN groups. In conclusion, supplementation ADY 4 g/head daily shift the rumen microbial composition of beef cattle fed low plane of nutrition to a more similar composition with cattle fed with HPN diet and produce the similar carcass weight with HPN diet.HighlightsThe ADY can improve the utilization of nitrogen and decrease the negative impact on the environment in beef cattle.Cattle fed low plane of nutrition diet supplemented with ADY 4 g/head daily increased growth performance.Supplementation ADY 4 g/head daily in low plane of nutrition diet might be produced comparable carcass weight to HPN diet.

20.
Curr Microbiol ; 78(3): 954-960, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33599832

RESUMO

Streptococcus pneumoniae (S. pneumoniae) is the main conditional pathogen of acute respiratory infection in infants, children, and older adults worldwide. It was great significant to identify the epidemic characteristics of serotypes and antibiotic susceptibility for the prevention and treatment of S. pneumoniae diseases. This research assessed the serotype distribution and the minimum inhibitory concentrations (MICs) of S. pneumoniae isolated from pediatric patients to provide information on the epidemiology and antibiotic resistance of S. pneumoniae in Kunming, China. A total of 140 S. pneumoniae isolates were collected from pediatric patients at Kunming Children's Hospital from January 2016 to October 2017. Serotype identification was done by Quellung reaction and multiplex polymerase chain reaction. MICs were determined by E-test. 140 isolates distributed in 13 types of serotypes. The top-three prevalent serotypes were 19F, 19A, and 6B. The immunization coverage rate of 13-valent pneumococcal conjugate vaccine (PCV) was relatively higher and should be introduced into the vaccination program in the region. MIC50 of penicillin, ceftriaxone, and levofloxacin was 1 µg/mL. MIC50 for meropenem and vancomycin was 0.38 µg/mL. MIC90 of penicillin, ceftriaxone, and levofloxacin was 1.5 µg/mL and that of meropenem and vancomycin was 0.5 µg/mL. The MIC90 of erythromycin was > 256 µg/mL. In summary, S. pneumoniae had low resistance rates to penicillin, ceftriaxone, levofloxacin, vancomycin, and meropenem, and these antibiotics could be the first-line agents for children with pneumococcal infections in Kunming.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Idoso , Antibacterianos/farmacologia , Criança , China/epidemiologia , Humanos , Lactente , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/epidemiologia , Sorogrupo , Sorotipagem
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