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1.
Transl Androl Urol ; 11(4): 472-479, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35558270

RESUMO

Background: It remains controversial whether there is a difference in the prognosis of intracytoplasmic sperm injection (ICSI) using frozen or fresh testicular sperm in patients with obstructive azoospermia (OA). Moreover, in the available studies, few have tracked neonatal outcomes. This study aimed to compare the pregnancy and neonatal outcomes of ICSI using cryopreserved sperm versus fresh sperm collected by testicular sperm aspiration (TESA). Methods: A total of 317 OA patients treated with ICSI in a university affiliated hospital from January 2016 to December 2020 were included in this study. The participants were divided into two groups according to the type of sperm used for ICSI: frozen sperm group (n=154) and fresh sperm group (n=163). The pregnancy and neonatal outcomes of the two groups were compared. Results: The data produced by this study showed no significant statistical difference in the 2 pronuclei (2PN) fertilization rate, 2PN cleavage rate, high-quality blastocyst rate, and the average number of transferred embryos in the frozen and fresh sperm groups. Similarly, no difference was found in implantation rate, clinical pregnancy rate, multiple pregnancy rate, miscarriage rate, premature delivery rate, live birth rate, and gender ratio at birth (P>0.05). The average newborn birth weight was similar in both groups (2,932.61±728.40 vs. 3,100.32±515.64 g, respectively) (P>0.05). A higher incidence of low birthweight (LBW) newborns was found in the frozen sperm group (20.91% vs. 8.49%) (P<0.05). Multiple logistic regression analysis showed that LBW is related to single or twin pregnancies (P<0.01), but not sperm (frozen or fresh) (P>0.05). We further analyzed the twin and single pregnancies in the two groups separately, and found that the incidences of LBW were both similar (P>0.05). There was no difference in the Apgar scores at 1 min and 5 min after birth between the two groups (P>0.05). Conclusions: The use of frozen testicular sperm by TESA was efficient for men with OA. There were similar pregnancy and neonatal outcomes following TESA-ICSI using frozen or fresh sperm in this retrospective study. Prospective investigations are needed for further validation.

2.
PLoS One ; 17(5): e0266752, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35544468

RESUMO

To increase power and minimize bias in statistical analyses, quantitative outcomes are often adjusted for precision and confounding variables using standard regression approaches. The outcome is modeled as a linear function of the precision variables and confounders; however, for many complex phenotypes, the assumptions of the linear regression models are not always met. As an alternative, we used neural networks for the modeling of complex phenotypes and covariate adjustments. We compared the prediction accuracy of the neural network models to that of classical approaches based on linear regression. Using data from the UK Biobank, COPDGene study, and Childhood Asthma Management Program (CAMP), we examined the features of neural networks in this context and compared them with traditional regression approaches for prediction of three outcomes: forced expiratory volume in one second (FEV1), age at smoking cessation, and log transformation of age at smoking cessation (due to age at smoking cessation being right-skewed). We used mean squared error to compare neural network and regression models, and found the models performed similarly unless the observed distribution of the phenotype was skewed, in which case the neural network had smaller mean squared error. Our results suggest neural network models have an advantage over standard regression approaches when the phenotypic distribution is skewed. However, when the distribution is not skewed, the approaches performed similarly. Our findings are relevant to studies that analyze phenotypes that are skewed by nature or where the phenotype of interest is skewed as a result of the ascertainment condition.

3.
Artigo em Inglês | MEDLINE | ID: mdl-35504991

RESUMO

This work was the first to report twelve natural estrogens (NEs) in the urines of six threatened or endangered mammalians in a Zoo Park of Guangzhou (i.e., panda, gorilla, elephant, African lion, jaguar, and leopard). Ten out of twelve NEs were detected at least in one urine sample of the six mammalians studied, including the four major NEs (i.e., estrone (E1), 17ß-estradiol (E2), 17α-estradiol (αE2), estriol (E3)), and six other NEs (i.e., 4-hydroxyestrone (4OHE1), 2-hydroxyestradiol (2OHE2), 4-hydroxyestradiol (4OHE2), 16α-hydroxyestrone (16α-OHE1), 16ketoestradiol (16ketoE2), and 17epiestriol (17epiE3)). The six studied mammalians, ranked in the order of high to low urinary concentration of total NEs, were jaguar, African lion, gorilla, elephant, panda, and leopard, with respective urinary concentrations of 110.4, 86.4, 71.4, 66.0, 55.9, and 52.8 ng/mL. According to the average urinary concentration of NE in the six mammalians ranked from high to low, the top five NEs detected were 16α-OHE1, 4OHE1, E1, E3, and 17epiE3, respectively. These clearly indicated the occurrence of NEs other than the four major types in urines of animals in a Zoo Park. Moreover, the daily excretion rates of the five detected NEs by one elephant ranged from 1162-2254 µg/d with a total daily excretion rate of 8260 µg/d, suggesting that the total urinary excretion of NEs by one adult elephant was equivalent to that by 170 premenopausal women or 506 adult men. Consequently, it appears from this study that NEs in the urines of zoo animals should be considered an emerging source of NEs.

4.
Ultrasonics ; 124: 106749, 2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35405598

RESUMO

The coronavirus Covid-19 mutates quickly in the pandemic, leaves people struggling to verify and improve the effectiveness of the vaccine based on biochemistry. Is there any physical invariant in the variants of such kind of pathogen that could be taken advantage to ease the tensions? To this point, extensive numerical experiments based on continuity mechanics have been accomplished to discover the consistent vibration modes and the range of natural frequency of coronavirus Covid-19. Such invariant could help us in developing some flexible technique to deactivate the coronavirus, like as resonantly breaking the viral spike by ultrasound wave. The fundamental mechanisms governing such process are demonstrated via solving the coupled acoustic wave and elastic dynamic equations, after which the practical strategies are proposed to efficiently realize the technique concept.

5.
Food Chem ; 387: 132930, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35436688

RESUMO

The fan training system with multiple trunks (F-MT) is widely used in the northern China winegrape region with high yield and convenience for burying soil to prevent winter cold. However, the wide distribution of clusters under F-MT usually leads to variations in berry compositions. In two consecutive years, clusters from different spatial positions were collected to determine the phenolic composition in grapes and resultant wines by HPLC-QqQ-MS/MS. Results showed that light exposure promotes the accumulation of flavonols and 3'-hydroxylated anthocyanins in berries. Wines made from upper clusters had higher alcohol degree, lightness, monomeric anthocyanins and flavonols, whereas wines made from lower clusters had relatively higher total acidity, red color component, polymeric anthocyanin and total flavanols. Most of the wine parameters were also significantly affected by vintage. In conclusion, the quality of grapes and wines varied from different cluster positions, graded harvesting helps to maximize the characteristics of grape berries.


Assuntos
Vitis , Vinho , Antocianinas/análise , Flavonóis/análise , Frutas/química , Fenóis/análise , Espectrometria de Massas em Tandem , Vinho/análise
6.
Nat Commun ; 13(1): 1341, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35292628

RESUMO

In recent years, increasing attention has been given to the potential supply risks of critical battery materials, such as cobalt, for electric mobility transitions. While battery technology and recycling advancement are two widely acknowledged strategies for addressing such supply risks, the extent to which they will relieve global and regional cobalt demand-supply imbalance remains poorly understood. Here, we address this gap by simulating historical (1998-2019) and future (2020-2050) global cobalt cycles covering both traditional and emerging end uses with regional resolution (China, the U.S., Japan, the EU, and the rest of the world). We show that cobalt-free batteries and recycling progress can indeed significantly alleviate long-term cobalt supply risks. However, the cobalt supply shortage appears inevitable in the short- to medium-term (during 2028-2033), even under the most technologically optimistic scenario. Our results reveal varying cobalt supply security levels by region and indicate the urgency of boosting primary cobalt supply to ensure global e-mobility ambitions.


Assuntos
Cobalto , Lítio , Fontes de Energia Elétrica , Reciclagem , Tecnologia
7.
Parasit Vectors ; 15(1): 70, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35236404

RESUMO

BACKGROUND: Ancylostoma species are hematophagous parasites that cause chronic hemorrhage in various animals and humans. Pangolins, also known as scaly anteaters, are mammals that live in soil environments where they are readily exposed to soil-borne parasitic nematodes. However, only a limited number of helminth species have been identified in this animal host so far. METHODS: Ancylostoma sp. was isolated from a wild pangolin, and the complete mitochondrial (mt) genome of Ancylostoma sp. was obtained by Illumina sequencing of total genomic DNA. RESULTS: The circular complete mt genome that was assembled had a total length of 13,757 bp and comprised 12 protein-coding genes (PCGs), 22 transfer ribosomal RNAs, two ribosomal RNAs (rRNAs), two non-coding regions and one AT-rich region, but lacked the gene coding for ATPase subunit 8 (atp8). The overall AT content of the mt genome of Ancylostoma sp. was 76%, which is similar to that of other nematodes. The PCGs used two start codons (ATT and TTG) and three stop codons (TAA, TAG, and T). The nucleotide identity of the 12 PCGs ranged from 83.1% to 89.7% and had the highest sequence identity with Ancylostoma caninum among species in the Ancylostomatidae family. Also, the pangolin-derived Ancylostoma sp. lacked repeat sequences in the non-coding regions and in the unique sequence of the short non-coding regions, which differentiated it from other Ancylostoma species. In addition, phylogenetic analyses of 18S rRNA and mtDNA sequences revealed that the Ancylostoma sp. was positioned in a separate branch in the subfamily Ancylostomatinae along with other Ancylostoma species. CONCLUSIONS: The Ancylostoma sp. isolated from a pangolin in this study was identified as a possible new Ancylostoma species. The identification of this Ancylostoma sp. from pangolin enriches our knowledge of the species in the Ancylostomatidae family and provides information that will lead to a better understanding of the taxonomy, diagnostics, and biology of hookworms.


Assuntos
DNA Mitocondrial , Genoma Mitocondrial , Ancylostoma/genética , Animais , DNA Mitocondrial/genética , Humanos , Pangolins , Filogenia , Análise de Sequência de DNA
8.
Sci Total Environ ; 829: 154657, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35314239

RESUMO

BACKGROUND: Ambient particulate matter (PM), especially its carbonaceous composition black carbon (BC) increases cardiometabolic risks, yet the underlying mechanisms are incompletely understood. Ceramides (Cer; a class of sphingolipids) are biological intermediates in glucose metabolism. OBJECTIVES: To explore whether Cer metabolism mediates impaired glucose homeostasis following short-term PM exposure. METHODS: In a panel study in Beijing, China, 112 participants were followed-up between 2016 and 2017. Targeted lipidomic analyses quantified 26 sphingolipids in 387 plasma samples. Ambient BC and PM with aerodynamic diameter ≤ 2.5 µm (PM2.5) were continuously monitored in a station. We examined the associations of sphingolipid levels with average BC and PM2.5 concentrations 1-14 days before clinical visits using linear mixed-effects models, and explored the mediation effects of sphingolipids on PM-associated fasting blood glucose (FBG) difference using mediation analyses. RESULTS: Increased levels of FBG and multiple sphingolipids in Cer metabolic pathways were associated with BC exposure in 1-14-day time window, but not with PM2.5 exposure. For each 10 µg/m3 increase in the average BC concentration 1-14 days before the clinical visits, species in the Cer C24:1 pathway (Cer, dihydroceramide, hexosylceramide, lactosylceramide, and sphingomyelin C24:1) increased in levels ranging from 11.8% (95% confidence interval [CI]: -6.2-33.2) to 48.7% (95% CI: 8.8-103.4), as did the Cer C16:0, C18:0, and C20:0 metabolic pathway species, ranging from 3.2% (95% CI: -5.6-12.9) to 32.4% (95% CI: 7.0-63.8), respectively. The Cer C24:1 metabolic pathway species mediated 6.5-25.5% of the FBG increase associated with BC exposure in 9-day time window. The Cer C16:0, C18:0, and C20:0 metabolic pathway species mediated 5.4-26.2% of the BC-associated FBG difference. CONCLUSIONS: In conclusion, Cer metabolism may mediate impaired glucose homeostasis following short-term BC exposure. The current findings are preliminary, which need to be corroborated by further studies.

9.
Artigo em Inglês | MEDLINE | ID: mdl-35349455

RESUMO

This article investigates the asynchronous proportional-integral observer (PIO) design issue for singularly perturbed complex networks (SPCNs) subject to cyberattacks. The switching topology of SPCNs is regulated by a nonhomogeneous Markov switching process, whose time-varying transition probabilities are polytope structured. Besides, the multiple scalar Winner processes are applied to character the stochastic disturbances of the inner linking strengths. Two mutually independent Bernoulli stochastic variables are exploited to characterize the random occurrences of cyberattacks. In a practical viewpoint, by resorting to the hidden nonhomogeneous Markov model, an asynchronous PIO is formulated. Under such a framework, by applying the Lyapunov theory, sufficient conditions are established such that the augmented dynamic is mean-square exponentially ultimately bounded. Finally, the effectiveness of the theoretical results is verified by two numerical simulations.

10.
Phytomedicine ; 99: 154025, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35272244

RESUMO

BACKGROUND: Microglia-related neuroinflammation is associated with a variety of neurodegenerative diseases. Flavonoids have demonstrated different pharmacological effects, such as antioxidation, neuroprotection and anti-inflammation However, the effect of flavonoid 6-methoxyflavone (6-MeOF) on microglia-mediated neuroinflammation remain unknown. PURPOSE: The current study aim to study the antineuroinflammatory effects of 6-MeOF in lipopolysaccharide- (LPS-) induced microglia in vitro and in vivo. METHODS: Pretreatment of BV2 microglia cells with 6-MeOF for 1 h then stimulated with LPS (100 ng/ml) for 24 h. The expression levels of pro-inflammatory factors, NO and reactive oxygen species (ROS) were performed by the enzyme-linked immunosorbent assay (ELISA), Griess assay and flow cytometry. Western blotting was used to assess MAPK, NF-κB signal transducer and antioxidant enzymes-related proteins. Analysis of ROS and microglial morphology was confirmed in the zebrafish and mice brain, respectively. RESULTS: Our results demonstrated that 6-MeOF dose-dependently prevent cell death and decreased the levels of pro-inflammatory mediators in LPS-stimulated BV2 microglia cells. Phosphorylated NF-κB/IκB and TLR4/MyD88/p38 MAPK/JNK proteins after exposure to 6-MeOF was suppressed in LPS-activated BV-2 microglial cells. 6-MeOF also presented antioxidant activity by reduction of NO, ROS, iNOS and COX-2 and the induction of the level of HO-1 and NQO1 expressions in LPS-activated BV2 microglial cells. Furthermore, we demonstrated that 6-MeOF inhibited LPS-induced NO generation in an experimental zebrafish model and prevent the LPS-induced microgliosis in the prefrontal cortex and substantia nigra of mice. CONCLUSION: These results explored that 6-MeOF possesses potential as anti-inflammatory and anti-oxidant agents against microglia-associated neuroinflammatory disorders.

11.
Hypertension ; 79(5): 1079-1090, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35193365

RESUMO

BACKGROUND: Vascular dysfunction is a biological pathway whereby particulate matter (PM) exerts deleterious cardiovascular effects. The effects of ambient PM on vascular function in prediabetic individuals are unclear. METHODS: A panel study recruited 112 Beijing residents with and without prediabetes. Multiple vascular function indices were measured up to 7 times. The associations between vascular function indices and short-term exposure to ambient PM, including fine particulate matter (PM2.5), ultrafine particles, accumulation mode particles, and black carbon, and the modification of these associations by glucose metabolic status were examined using linear mixed-effects models. RESULTS: Increases in brachial artery pulse pressure, central aortic pulse pressure, and ejection duration, and decreases in subendocardial viability ratio and reactive hyperemia index were significantly associated with at least one PM pollutant in all participants, indicating increased vascular dysfunction. For example, for an interquartile range increment in 5-day moving average ultrafine particles, brachial artery pulse pressure, and central aortic pulse pressure increased 5.4% (0.8%-10.4%) and 6.2% (1.2%-11.5%), respectively. Additionally, PM-associated changes in vascular function differed according to glucose metabolic status. Among participants with high fasting blood glucose levels (≥6.1 mmol/L), PM exposure was significantly associated with increased brachial artery systolic blood pressure, central aortic systolic blood pressure, brachial artery pulse pressure, central aortic pulse pressure, and augmentation pressure normalized to a heart rate of 75 bpm and decreased subendocardial viability ratio and reactive hyperemia index. Weaker or null associations were observed in the low-fasting blood glucose group. CONCLUSIONS: Glucose metabolic disorders may exacerbate vascular dysfunction associated with short-term ambient PM exposure.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Hiperemia , Estado Pré-Diabético , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Glicemia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Frequência Cardíaca , Humanos , Material Particulado/efeitos adversos , Material Particulado/análise
12.
J Cell Mol Med ; 26(7): 1994-2009, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35174626

RESUMO

The regulation of renal function by circadian gene BMAL1 has been recently recognized; however, the role and mechanism of BMAL1 in renal ischaemia-reperfusion injury (IRI) are still unknown. The purpose of this study was to clarify the pathophysiological role of BMAL1 in renal IRI. We measured the levels of BMAL1 and mitochondrial biogenesis-related proteins, including SIRT1, PGC-1α, NRF1 and TFAM, in rats with renal IRI. In rats, the level of BMAL1 decreased significantly, resulting in inhibition of SIRT1 expression and mitochondrial biogenesis. In addition, under hypoxia and reoxygenation (H/R) stimulation, BMAL1 knockdown decreased the level of SIRT1 and exacerbated the degree of mitochondrial damage and apoptosis. Overexpression of BMAL1 alleviated H/R-induced injury. Furthermore, application of the SIRT1 inhibitor EX527 not only reduced the activities of SIRT1 and PGC-1α but also further aggravated mitochondrial dysfunction and partially reversed the protective effect of BMAL1 overexpression. Moreover, whether in vivo or in vitro, the application of SIRT1 agonist resveratrol rescued the mitochondrial dysfunction caused by H/R or IRI by activating mitochondrial biogenesis. These results indicate that BMAL1 is a key circadian gene that mediates mitochondrial homeostasis in renal IRI through the SIRT1/PGC-1α axis, which provides a new direction for targeted therapy for renal IRI.


Assuntos
Fatores de Transcrição ARNTL , Rim , Traumatismo por Reperfusão , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Animais , Homeostase , Rim/metabolismo , Rim/fisiopatologia , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Ratos , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo
13.
Front Oncol ; 12: 804632, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35223484

RESUMO

PURPOSE: To validate the feasibility of S-Detect, an ultrasound computer-aided diagnosis (CAD) system using deep learning, in enhancing the diagnostic performance of breast ultrasound (US) for patients with opportunistic screening-detected breast lesions. METHODS: Nine medical centers throughout China participated in this prospective study. Asymptomatic patients with US-detected breast masses were enrolled and received conventional US, S-Detect, and strain elastography subsequently. The final pathological results are referred to as the gold standard for classifying breast mass. The diagnostic performances of the three methods and the combination of S-Detect and elastography were evaluated and compared, including sensitivity, specificity, and area under the receiver operating characteristics (AUC) curve. We also compared the diagnostic performances of S-Detect among different study sites. RESULTS: A total of 757 patients were enrolled, including 460 benign and 297 malignant cases. S-Detect exhibited significantly higher AUC and specificity than conventional US (AUC, S-Detect 0.83 [0.80-0.85] vs. US 0.74 [0.70-0.77], p < 0.0001; specificity, S-Detect 74.35% [70.10%-78.28%] vs. US 54.13% [51.42%-60.29%], p < 0.0001), with no decrease in sensitivity. In comparison to that of S-Detect alone, the AUC value significantly was enhanced after combining elastography and S-Detect (0.87 [0.84-0.90]), without compromising specificity (73.93% [68.60%-78.78%]). Significant differences in the S-Detect's performance were also observed across different study sites (AUC of S-Detect in Groups 1-4: 0.89 [0.84-0.93], 0.84 [0.77-0.89], 0.85 [0.76-0.92], 0.75 [0.69-0.80]; p [1 vs. 4] < 0.0001, p [2 vs. 4] = 0.0165, p [3 vs. 4] = 0.0157). CONCLUSIONS: Compared with the conventional US, S-Detect presented higher overall accuracy and specificity. After S-Detect and strain elastography were combined, the performance could be further enhanced. The performances of S-Detect also varied among different centers.

14.
Am J Primatol ; 84(3): e23360, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35166397

RESUMO

Gut microbiota influences nutrient metabolism and immunity of animal hosts. Better understanding of the composition and diversity of gut microbiota contributes to conservation and management of threatened animals both in situ and ex situ. In this study, we applied 16S rRNA gene amplicon sequencing to evaluate the composition and diversity of the fecal bacterial community of four gibbon genera (Family Hylobatidae) at four Chinese zoos. The results showed that the dominant bacterial phyla were Bacteroidetes, Firmicutes, and Proteobacteria and dominant families were Prevotellaceae (Bacteroidetes), Spirochaetaceae (Spirochaetes) and Ruminococcaceae (Firmicutes) in the gut of all gibbons. Both captive site and host genus had significant effects on the relative abundance of dominant bacteria and structure of gut bacterial community. We found that captive site and host genus did not solely impact gut bacterial diversity, but the interaction between them did. This study provides basic knowledge for gut microbiota of all four gibbon genera and contributes to management and conservation of captive gibbons.


Assuntos
Microbioma Gastrointestinal , Animais , Bactérias/genética , China , Firmicutes/genética , Microbioma Gastrointestinal/genética , Humanos , Hylobates , RNA Ribossômico 16S/genética
15.
Artigo em Inglês | MEDLINE | ID: mdl-35206308

RESUMO

The CO2 emission-mitigation policies adopted in different Chinese cities are important for achieving national emission-mitigation targets. China faces enormous inequalities in terms of regional economic development and urbanization, with some cities growing rapidly, while others are shrinking. This study selects 280 cities in China and divides them into two groups of growing cities and two groups of shrinking cities. This is achieved using an index called "urban development degree," which is calculated based on economic, demographic, social, and land-use indicators. Then, the 280 cities' CO2 emission characteristics are examined, and extended STIRPAT (stochastic impacts by regression on population, affluence, and technology) is used to verify the influencing factors. We find that rapidly growing cities (RGCs) present a trend of fluctuating growth in CO2 emissions, rapidly shrinking cities (RSCs) show an inverted U-shaped trend, and slightly growing (SGCs) and slightly shrinking cities (SSCs) show a trend of rising first, followed by steady development. Moreover, for growing cities, the population, economy, and proportion of tertiary industry have positive effects on carbon emissions, while technology has negative effects. For shrinking cities, the population and economy have significant positive effects on carbon emissions, while technology and the proportion of tertiary industry have negative effects.


Assuntos
Dióxido de Carbono , Carbono , Dióxido de Carbono/análise , China , Cidades , Desenvolvimento Econômico , Urbanização
16.
Opt Express ; 30(2): 2278-2287, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209371

RESUMO

Saturable absorber (SA) based harmonic mode-locking (HML) techniques at 2 µm waveband are much less reported than those at 1.5 µm waveband, the maximum repetition rate of the harmonic pulse generated by such techniques at 2 µm waveband is also much lower than those generated at 1.5 µm waveband. In this paper, the 39th harmonic with the repetition rate of 908.6 MHz is realized in a Bi2S3-based thulium-doped fiber laser. The fundamental mode-locked pulse has a central wavelength of 1954.2 nm and a 3-dB bandwidth of 5.1 nm. The repetition rate is 23.27 MHz and the pulse width is 902 fs. The characteristics of the material and harmonic mode-locked pulse are investigated. To the best of our knowledge, this is the highest and the closest resonance frequency to GHz among the reported SA-based harmonic mode-locked fiber lasers operating at 2 µm waveband.

17.
Carbohydr Polym ; 278: 118910, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34973731

RESUMO

Staphylococcus aureus (S. aureus) is the major pathogen responsible for mastitis in dairy cows, an important threat to their health, but prevention of S. aureus infection of the mammary gland remains challenging. Berberine hydrochloride (BH), a naturally occurring phytochemical, exhibits a wide range of activities, including antibacterial effects on S. aureus. In this study, we prepared a novel berberine hydrochloride-carboxymethyl chitosan hydrogel (BH-CMCH) with excellent thermosensitivity, injectability and in vitro antibacterial activity. In a rat model of mastitis induced by S. aureus, mammary duct injection of BH-CMCH reduced the bacterial load in infected mammary gland tissue and protected the tissue from damage from infection. In addition, proteomics analysis showed that mammary duct injection of BH-CMCH enhanced autolysosome degradation and promoted the innate immune response by activating the lysosomal pathway and up-regulating related significantly differentially expressed proteins (SDEPs). Taken together, the findings support the potential of BH-CMCH as an antibacterial agent against S. aureus-induced mastitis.


Assuntos
Antibacterianos/farmacologia , Berberina/farmacologia , Quitosana/análogos & derivados , Hidrogéis/farmacologia , Mastite/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/síntese química , Antibacterianos/química , Berberina/química , Quitosana/química , Quitosana/farmacologia , Feminino , Hidrogéis/síntese química , Hidrogéis/química , Testes de Sensibilidade Microbiana , Ratos , Ratos Sprague-Dawley
18.
Anal Bioanal Chem ; 414(6): 2041-2054, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35066602

RESUMO

Sphingolipids are a class of lipids with high structural diversity and biological pleiotropy. Mounting evidence supports a role for sphingolipids in regulating pathophysiology of cardiometabolic diseases, and they have been proposed as potential cardiometabolic biomarkers. Current methods for quantifying sphingolipids require laborious pretreatment and relatively large sample volumes, and cover limited species, hindering their application in epidemiological studies. Herein, we applied a time-, labor-, and sample-saving protocol simply using methanol for plasma sphingolipid extraction. It was compared with classical liquid-liquid extraction methods and showed significant advantages in terms of simplicity, sphingolipid coverage, and sample volume. By coupling the protocol with liquid chromatography using a wide-span mobile phase polarity parameter and tandem mass spectrometry operated in dynamic multiple reaction monitoring mode, 37 sphingolipids from 8 classes (sphingoid base, sphingoid base phosphate, ceramide-1-phosphate, lactosylceramide, hexosylceramide, sphingomyelin, ceramide, and dihydroceramide) were quantified within 16 min, using only 10 µL of human plasma. The current method showed good performance in terms of linearity (R2 > 0.99), intra- and interbatch accuracy (70-123%) and precision (RSD < 12%), matrix effect (91-121%), recovery (96-101%), analyte chemical stability (deviation < 19%), and carryover (< 16%). We successfully applied this method to quantify 33 detectable sphingolipids from 579 plasma samples of an epidemiological study within 10 days. The quantified sphingolipid concentrations were comparable with previous studies. Positive associations of ceramide C22:0/C24:0 and their precursors with homeostasis model assessment of insulin resistance suggested that the synthesis of the ceramides might be involved in insulin resistance. This novel method constitutes a simple and rapid approach to quantify circulating sphingolipids for epidemiological studies using targeted lipidomic analysis, which will help elucidate the sphingolipid-regulated pathways underlying cardiometabolic diseases.


Assuntos
Esfingolipídeos , Espectrometria de Massas em Tandem , Ceramidas/análise , Cromatografia Líquida/métodos , Humanos , Lipidômica , Extração Líquido-Líquido , Esfingolipídeos/análise , Espectrometria de Massas em Tandem/métodos
19.
Acad Radiol ; 29 Suppl 1: S1-S7, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33384211

RESUMO

RATIONALE AND OBJECTIVES: The sonographic appearance of benign and malignant breast nodules overlaps to some extent, and we aimed to assess the performance of the Gail model as an adjunctive tool to ultrasound (US) Breast Imaging Reporting and Data System (BI-RADS) for predicting the malignancy of nodules. MATERIALS AND METHODS: From 2018 to 2019, 2607 patients were prospectively enrolled by 35 health care facilities. An individual breast cancer risk was assessed by the Gail model. Based on B-mode US, color Doppler, and elastography, all nodules were evaluated according to the fifth edition of BI-RADS, and these nodules were all confirmed later by pathology. RESULTS: We demonstrated that the Gail model, age, tumor size, tumor shape, growth orientation, margin, contour, acoustic shadowing, microcalcification, presence of duct ectasia, presence of architectural distortion, color Doppler flow, BI-RADS, and elastography score were significantly related to breast cancer (all p < 0.001). The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and area under the curve (AUC) for combining the Gail model with the BI-RADS category were 95.6%, 91.3%, 85.0%, 97.6%, 92.8%, and 0.98, respectively. Combining the Gail model with the BI-RADS showed better diagnostic efficiency than the BI-RADS and Gail model alone (AUC 0.98 vs 0.80, p < 0.001; AUC 0.98 vs 0.55, p < 0.001) and demonstrated a higher specificity than the BI-RADS (91.3% vs 59.4%, p < 0.001). CONCLUSION: The Gail model could be used to differentiate malignant and benign breast lesions. Combined with the BI-RADS category, the Gail model was adjunctive to US for predicting breast lesions for malignancy. For the diagnosis of malignancy, more attention should be paid to high-risk patients with breast lesions.


Assuntos
Neoplasias da Mama , Técnicas de Imagem por Elasticidade , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Diagnóstico Diferencial , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Estudos Prospectivos , Sensibilidade e Especificidade , Ultrassonografia Mamária/métodos
20.
Environ Technol ; : 1-14, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34873998

RESUMO

A batch experiment was used in studying the effect of acrylic-acid-modified walnut shell (MWNS) as a low-cost adsorbent for removing Rhodamine B (RB) cationic dye in aqueous solutions. The adsorbent dosage, initial dye concentration, contact time, temperature, pH, and supporting electrolyte concentration on the adsorption behaviour of the adsorbent were explored. The adsorbent was characterized using the point of zero charge (pHPZC), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), automatic specific surface analysis (BET), and X-ray photoelectron spectroscopy (XPS). Results showed that MWNS had abundant active groups and rough surface, which is conducive to the adsorption process. The kinetics and equilibrium data of MWNS-to-RB adsorption were in accordance pseudo-second-order kinetic and Freundlich isotherm models, respectively. Under optimal adsorption conditions, the maximum adsorption capacity of RB was 48.87 mg·g-1. Thermodynamic results showed spontaneously and exothermically the adsorption process. Moreover, the addition of electrolyte had a negative effect on equilibrium adsorption capacity and adsorption rate.HIGHLIGHTS Acrylic-acid-modified walnut shells was used as an adsorbent for the removal of Rhodamine B (RB).The adsorption of RB by modified walnut shells was greatly affected by pH.Pseudo-second-order kinetic and Freundlich model fit the experimental data.The modified walnut shell can remove RB through electrostatic attraction, hydrogen bonding, and electron donor-acceptor interaction.

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