Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.208
Filtrar
1.
Brain Imaging Behav ; 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33048290

RESUMO

Depression is one of the common incidental symptoms in end-stage renal disease (ESRD) patients, empirically overlooked. Reproducible results observed that altered interregional white matter (WM) connections between depression-related brain regions (thalamus, amygdala, and prefrontal cortex (PFC)) in the human brain were closely associated with depression. Whether the depressive tendency of ESRD patients is also association with the WM connections is remains unknown. To address this problem, 56 ESRD patients before dialysis initiation and 56 healthy controls (HCs) were scanned with diffusion tensor imaging. According to the diagnostic and statistical manual of mental disorders, ESRD patients were separated into with and without depressive tendency groups. Twenty-five essential metabolites were tested in ESRD. The tractography atlas-based analysis and multiple regression analysis were implemented to gain features which could map the depressive tendency variability across ESRD. For metabolites, the levels of thrombocytes and calcium have significant differences between with and without depressive tendency groups. For WM microstructure, depressive tendency ESRD patients had abnormal WM diffusion properties along the fiber tracts of the amygdala-PFC. Compared with the features which were extracted from the group-difference of WM or metabolites, only WM features combinations (1000 bootstrap samples; 5000 permutation tests) along the fiber tract of the amygdala-PFC was a significant predictor of either with or without depressive tendency. Our findings suggested that the advanced neuroprotection may be planned before dialysis initiation, and the WM characteristics of amygdala-PFC may be a potential neuromarkers for the early diagnosis of depressive tendency in ESRD patients before dialysis initiation.

2.
Inorg Chem ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33022178

RESUMO

Due to its great relevance to environmental, biological, and chemical processes, the precise detection of pH or acidic/basic species is an ongoing and imperative need. In this context, pH-sensitive luminescent systems are highly desired. We reported a three-dimensional Zn(II) MOF synthesized from a bipyridyl-tetracarboxylic ligand and composed of 4-fold interpenetrated diamond frameworks. Because the steric hindrance in the ligand prevents metal coordination with the pyridyl group, the MOF features free basic N sites accessible to the small H+ ions, which renders pH responsivity. The aqueous dispersion exhibits an abrupt, high-contrast, and reversible on-off fluorescence transition in the narrow pH range of 5.4-6.2. The sensitive bistable system can be used for the precise monitoring of pH within the range and for use as a pH-triggered optical switch. The responsive mechanism through pyridyl protonation is collaboratively supported by data fitting, absorption spectra, and molecular orbital calculations. In particular, spectral and theoretical analyses reveal the destruction of n → π* transitions and the appearance of intramolecular charge-transfer transitions upon pyridyl protonation. Moreover, by virtue of the pH-responsive fluorescence, the MOF shows appealing sensing performance for the detection of 3-nitropropionic acid, a major mycotoxin in moldy sugar cane.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33042862

RESUMO

Regulation of the environmental stress response and virulence of Shigella flexneri may involve multiple signaling pathways; however, these mechanisms are not well-defined. In bacteria, small regulatory RNAs (sRNAs) regulate bacterial growth, metabolism, virulence, and environmental stress response. Therefore, identifying novel functional sRNAs in S. flexneri could help elucidate pathogenic adaptations to host micro-environmental stresses and associated virulence. The aim of this study was to confirm the presence of an sRNA, Ssr54, in S. flexneri and to determine its functions and possible mechanism of action. Ssr54 was found to regulate tolerance and virulence under hyperosmotic pressure. Its expression was verified by qRT-PCR and Northern blotting, and its genomic position was confirmed by 5'-rapid amplification of cDNA ends. Ssr54 expression was significantly decreased (~ 80%) under hyperosmotic conditions (680 mM NaCl), and the survival rate of the Ssr54 deletion strain increased by 20% under these conditions. This suggested that Ssr54 has been selected to promote host survival under hyperosmotic conditions. Additionally, virulence assessment, including guinea pig Sereny test and competitive invasion assays in mouse lungs, revealed that Ssr54 deletion significantly decreased S. flexneri virulence. Two-dimensional gel analyses suggest that Ssr54 may modulate the expression of tolC, ompA, and treF genes, which may affect the virulence and survival of S. flexneri under osmotic pressures. Furthermore, treF expression has been shown to improve the survival of S. flexneri under osmotic pressures. These results suggest that Ssr54 has a broad range of action in S. flexneri response to hyperosmotic environmental stresses and in controlling its virulence to adapt to environmental stresses encountered during host infection.

4.
World J Gastroenterol ; 26(36): 5508-5519, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33024401

RESUMO

BACKGROUND: Gastric cancer (GC) is a heavy burden in China. Nutritional support for GC patients is closely related to postoperative rehabilitation. However, the role of early oral feeding after laparoscopic radical total gastrectomy in GC patients is unclear and high-quality research evidence is scarce. AIM: To prospectively explore the safety, feasibility and short-term clinical outcomes of early oral feeding after laparoscopic radical total gastrectomy for GC patients. METHODS: This study was a prospective cohort study conducted between January 2018 and December 2019 based in a high-volume tertiary hospital in China. A total of 206 patients who underwent laparoscopic radical total gastrectomy for GC were enrolled. Of which, 105 patients were given early oral feeding (EOF group) after surgery, and the other 101 patients were given the traditional feeding strategy (control group) after surgery. Perioperative clinical data were recorded and analyzed. The primary endpoints were gastrointestinal function recovery time and postoperative complications, and the secondary endpoints were postoperative nutritional status, length of hospital stay and expenses, etc. RESULTS: Compared with the control group, patients in the EOF group had a significantly shorter postoperative first exhaust time (2.48 ± 1.17 d vs 3.37 ± 1.42 d, P = 0.001) and first defecation time (3.83 ± 2.41 d vs 5.32 ± 2.70 d, P = 0. 004). In addition, the EOF group had a significant shorter postoperative hospitalization duration (5.85 ± 1.53 d vs 7.71 ± 1.56 d, P < 0.001) and lower postoperative hospitalization expenses (16.60 ± 5.10 K¥ vs 21.00 ± 7.50 K¥, P = 0.014). On the 5th day after surgery, serum prealbumin level (214.52 ± 22.47 mg/L vs 204.17 ± 20.62 mg/L, P = 0.018), serum gastrin level (246.30 ± 57.10 ng/L vs 223.60 ± 55.70 ng/L, P = 0.001) and serum motilin level (424.60 ± 68.30 ng/L vs 409.30 ± 61.70 ng/L, P = 0.002) were higher in the EOF group. However, there was no significant difference in the incidence of total postoperative complications between the two groups (P = 0.507). CONCLUSION: Early oral feeding after laparoscopic radical total gastrectomy can promote the recovery of gastrointestinal function, improve postoperative nutritional status, reduce length of hospital stay and expenses while not increasing the incidence of related complications, which indicates its safety, feasibility and potential benefits for gastric cancer patients.

5.
BMC Cancer ; 20(1): 968, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028275

RESUMO

BACKGROUND: Colon adenocarcinoma (COAD) patients who develop recurrence have poor prognosis. Our study aimed to establish effective prognosis prediction model based on competing endogenous RNAs (ceRNAs) for recurrence of COAD. METHODS: COAD expression profilings downloaded from The Cancer Genome Atlas (TCGA) were used as training dataset, and expression profilings of GSE29623 retrieved from Gene Expression Omnibus (GEO) were set as validation dataset. Differentially expressed RNAs (DERs) between non-recurrent and recurrent specimens in training dataset were screened, and optimum prognostic signature DERs were revealed to establish prognostic score (PS) model. Kaplan-Meier survival analysis was conducted for PS model, and GEO dataset was used for validation. Prognosis prediction efficiencies were evaluated by area under curve (AUC) and C-index. Meanwhile, ceRNA regulatory network was constructed by using signature mRNAs, lncRNAs and miRNAs. RESULTS: We identified 562 DERs including 42 lncRNAs, 36 miRNAs, and 484 mRNAs. PS prediction model, consisting of 17 optimum prognostic signature DERs, showed that high risk group had significantly poorer prognosis (5-year AUC = 0.951, C-index = 0.788), which also validated in GSE29623. Prognosis prediction model incorporating multi-RNAs with pathologic distant metastasis (M) and pathologic primary tumor (T) (5-year AUC = 0.969, C-index = 0.812) had better efficiency than clinical prognosis prediction model (5-year AUC = 0.712, C-index = 0.680). In the constructed ceRNA regulatory network, lncRNA NCBP2-AS1 could interact with hsa-miR-34c and hsa-miR-363, and lncRNA LINC00115 could interact with hsa-miR-363 and hsa-miR-4709. SIX4, GRAP, NKAIN4, MMAA, and ERVMER34-1 are regulated by hsa-miR-4709. CONCLUSION: Prognosis prediction model incorporating multi-RNAs with pathologic M and pathologic T may have great value in COAD prognosis prediction.

6.
Health Qual Life Outcomes ; 18(1): 330, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028344

RESUMO

PURPOSE: Physicians and Standardised Residency Training physicians (SRTPs) have relatively high exposure to psychological violence. Its adverse effects are far greater than those of physical violence. However, no previous research has paid attention to the problem of psychological violence among them. This study aims to evaluate the extent, characteristics, and risk factors of psychological violence among SRTPs in comparison to physicians, and also to highlight the psychological violence experienced by SRTPs and suggest preventive measures. METHODS: A cross-sectional survey was conducted in northern China. 884 physicians and 537 SRTPs completed a questionnaire which compiled by the ILO, ICN, WHO and PSI in 2003 to measure violence in the workplace. Descriptive statistics and logistic regression analysis were used to analyse results. RESULTS: The effective response rates of physicians and SRTPs were 63.1%(884/1400) and 86.3%(537/622) respectively. 73.0%(645/884) of physicians and 24.8%(133/537) of SRTPs suffered psychological violence in the past year. Compared to physicians (29/645, 4.5%), SRTPs (42/133, 31.6%) experience more internal violence. Further, after experiencing psychological violence, physicians are willing to talk to family and friends, but SRTPs generally take no action. Shift work was a risk factor for both physicians (OR 1.440, 95% CI 1.014-2.203) and SRTPs (OR 1.851, 95% CI 1.217-2.815) suffering from psychological violence. In contrast, no anxiety symptoms protected physicians (OR 0.406, 95% CI 0.209-0.789) and SRTPs (OR 0.404, 95% CI 0.170-0.959) against psychological violence. CONCLUSIONS: SRTPs and physicians in northern China have a high risk of experiencing psychological violence, and physicians experience more. Meanwhile, there are obvious differences in responses to psychological violence and risk factors between them. Therefore, medical institutions should pay more attention to psychological violence, especially among SRTPs, such as supporting the reporting of psychological violence, strengthening team relationships, and providing psychological comfort and counselling. Trial registration number (Project Identification Code: HMUIRB20160014), Registered May 10, 2016.

7.
Cancers (Basel) ; 12(10)2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33036247

RESUMO

Although immune checkpoint inhibitors and targeted therapeutics have changed the landscape of treatment for renal cell carcinoma (RCC), most patients do not experience significant clinical benefits. Emerging preclinical studies report that nutrition-based interventions and glucose-regulating agents can improve therapeutic efficacy. However, the impact of such agents on therapeutic efficacy in metastatic kidney cancer remains unclear. Here, we examined acarbose, an alpha-glucosidase inhibitor and antidiabetic agent, in a preclinical model of metastatic kidney cancer. We found that acarbose blunted postprandial blood glucose elevations in lean, nondiabetic mice and impeded the growth of orthotopic renal tumors, an outcome that was reversed by exogenous glucose administration. Delayed renal tumor outgrowth in mice on acarbose occurred in a CD8 T cell-dependent manner. Tumors from these mice exhibited increased frequencies of CD8 T cells that retained production of IFNγ, TNFα, perforin, and granzyme B. Combining acarbose with either anti-PD-1 or the mammalian target of rapamycin inhibitor, rapamycin, significantly reduced lung metastases relative to control mice on the same therapies. Our findings in mice suggest that combining acarbose with current RCC therapeutics may improve outcomes, warranting further study to determine whether acarbose can achieve similar responses in advanced RCC patients in a safe and likely cost-effective manner.

8.
Nanomaterials (Basel) ; 10(10)2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33036403

RESUMO

Wearable electronics, such as sensors, actuators, and supercapacitors, have attracted broad interest owing to their promising applications. Nevertheless, practical problems involving their sensitivity and stretchability remain as challenges. In this work, efforts were devoted to fabricating a highly stretchable and sensitive strain sensor based on dip-coating of graphene onto an electrospun thermoplastic polyurethane (TPU) nanofibrous membrane, followed by spinning of the TPU/graphene nanomembrane into an intertwined-coil configuration. Owing to the intertwined-coil configuration and the synergy of the two structures (nanoscale fiber gap and microscale twisting of the fiber gap), the conductive strain sensor showed a stretchability of 1100%. The self-inter-locking of the sensor prevents the coils from uncoiling. Thanks to the intertwined-coil configuration, most of the fibers were wrapped into the coils in the configuration, thus avoiding the falling off of graphene. This special configuration also endowed our strain sensor with an ability of recovery under a strain of 400%, which is higher than the stretching limit of knees and elbows in human motion. The strain sensor detected not only subtle movements (such as perceiving a pulse and identifying spoken words), but also large movements (such as recognizing the motion of fingers, wrists, knees, etc.), showing promising application potential to perform as flexible strain sensors.

9.
J Neurophysiol ; 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33026904

RESUMO

Auditory brainstem response (ABR) and cochlear compound action potential (CAP) are widely used for hearing assessment. Due to easy detection, ABR is more commonly used to evaluate cochlear lesions than CAP. Since ABR reflects the central auditory response in the brain, and CAP reflects the auditory nerve function of the cochlea, ABR is not the same as CAP. In order to see the difference between ABR and CAP, two cochlear injury models were observed. In ae noise-induced cochlear damage model, chinchillas were exposed to 105 dB SPL narrow-band noise for 5 hours. One day after the noise, the thresholds of CAP and ABR increased to the same level with permanent hair cell loss. 30 days later, the elevated CAP threshold remains unchanged, but the ABR threshold was significantly reduced about 20 dB. This phenomenon may be due to the irreversible weakening of CAP and the enhancement of ABR by central reorganizition. In another experimental model of unilateral cochlear destruction in guinea pigs, both ABR and CAP were affected by cross-hearing. When ABR was tested from the destroyed ear, a shadow-curve of ABR from the contralateral healthy ear masked the hearing loss in the destroyed ear. In contrast, the typical CAP waveform disappeared which was replaced by an ABR-like waveform from the opposite healthy ear. The results indicate that ABR may not faithfully reflect the functional status of the cochlea, and provide a clue of the occurrence of cross-hearing when subjects have asymmetric hearing loss.

10.
J Nat Prod ; 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33006888

RESUMO

Anti-cardiac fibrosis (CF) is one of the key therapeutic strategies for the treatment of various heart diseases. Therefore, development of drugs targeting CF is promising. However, there are very few studies that systemically explore effective drugs for CF. It has been known that many natural compounds display antifibrosis effects. In this work, we aim to build an integrated model for systematic pursuit of anti-CF agents from natural compounds. We first constructed a heart-specific CF marker-gene-centered functional gene module (HCFM) that represents a set of genes specifically involved in CF based on the CF marker genes and known gene coexpression knowledge. Then, we extracted transcriptional data induced by natural compounds from the Gene Expression Omnibus database. The anti-CF effects of compounds were evaluated by the correlation of HCFM in the compound-induced gene expression profiles by gene set enrichment analysis. Finally, the anti-CF effect of a top-predicted natural monomer, schisantherin A, was experimentally validated in the myocardial infarction animal model. This strategy integrating different types of technologies is expected to help create new opportunities for development of drugs targeting CF.

11.
Materials (Basel) ; 13(19)2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33008075

RESUMO

As a natural macromolecule-based biomaterial, fish gelatin is used in medical materials for its low pathogen infection risk. However, because of poor mechanical properties, its application has been limited. In this study, microcrystalline cellulose-reinforced fish gelatin (FG/MCC) composite films were prepared with a biological cross-linking agent (genipin) under ultrasonic treatment. SEM micrographs showed that the smooth microstructure of FG film became increasingly disordered with the addition of MCC. The infrared spectrum analysis (FTIR) demonstrated the existence of hydrogen bond interaction between MCC and FG. Compared with the pure FG film, the tensile strength (TS) and modulus of elasticity (MOE) of composite films with MCC were improved, and the elongation at break (EAB) and swelling ratios (SR) were decreased. Ultrasonic treatment could further improve TS, MOE, and SR. When the composite film was prepared with 15% MCC and treated with ultrasound, the TS and MOE increased by 115% and 227%, respectively, while the EAB decreased by 35% and the SR decreased by 4% in comparison with pure FG films. Thermo-gravimetric analysis (TGA) showed that the FG/MCC composite films were stable below 100 °C. The above results indicate that the FG/MCC films have optimistic application prospects in the biomedical field.

12.
Chin J Traumatol ; 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-33008740

RESUMO

PURPOSE: Several researches comparing the imageless navigation (IN) system and manual freehand (MF) approaches for the total hip arthroplasty (THA) have been published, but the curative effect is still contentious. This meta-analysis aims to systematically compare the differences between the two approaches. METHODS: Random controlled trials which compared the clinical efficacy between IN and MF approaches for THA were retrieved between June 1999 and June 2019, from PubMed, Embase, Cochrane Library, etc. Mean difference, odds ratio and corresponding 95% confidence intervals (CI) were used for estimating the effects of the two methods. I2 test and Chi-square test were used to test heterogeneity among studies. Statistical analyses were done using Review Manager Version 5.3. RESULTS: Eleven pieces of literature were presented. No statistical variation in IN and MF approaches on Harris hip score (HHS) (95% CI: -2.91, 1.47; p = 0.52), cup inclination (95% CI: -0.60, 1.95; p = 0.30), cup anteversion (95% CI: -2.85, 0.91; p = 0.31), cup abduction (95% CI: -3.65, 0.63; p = 0.17), length of incision (95% CI: -0.25, 0.29; p = 0.90), blood loss (95% CI: -69.14, 25.61; p = 0.37) and the decrease of hemoglobin (Hb) at 24 h after surgery (95% CI: -0.45, 0.40; p = 0.91), etc. However, the number of cases outside the safe zone in the IN group were less than in the MF group (95% CI: 0.08, 0.25; p < 0.00001). The deviation of cup inclination/anteversion in the IN group was smaller than in the MF group (95% CI: -3.65, -0.52; p = 0.009) vs. (95% CI: -6.16, 1.91; p = 0.0002). But the operation time in the IN group was longer than in the MF group (95% CI: 5.47, 11.60; p < 0.00001). CONCLUSIONS: IN system is more accurate than MF approaches in THA, but IN system needs more operation time. There is no difference between the approaches on HHS, cup inclination, cup anteversion, length of incision, blood loss and the decrease of Hb at 24 h after surgery.

13.
Hum Pathol ; 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33010300

RESUMO

Hepatic involvement by a T-cell neoplasm is rare and often challenging to diagnose in liver biopsies. We collected 40 cases of T-cell neoplasms diagnosed in the liver from five large academic institutions to assess the clinicopathologic features. The patients included 11 females and 29 males, with a median age of 54 (range 2-75) years and a high mortality rate (31/37, 83.8%). Fourteen (35%) patients were diagnosed with hepatosplenic T-cell lymphoma (HSTCL), 13 (32.5%) peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), and 13 (32.5%) other types of T-cell neoplasms. Patients with HSTCL were much younger and had worse survival than PTCL-NOS and other T-cell neoplasms (P<0.05). On imaging studies, 20 cases (50%) showed abnormalities, including 10 with mass lesions that correlated with normal or cholestatic pattern enzyme elevation. Histomorphological analysis revealed four main patterns; with the exception of mass forming lesions (pattern 4; n=8), cases with sinusoidal predominant (pattern 1; n=12), portal predominant with sinusoidal infiltrates (pattern 2; n=13) or lobular aggregates (pattern 3; n=5) demonstrated small to medium lymphocytes resembling a reactive/inflammatory process. In addition, we described two cases of T-cell large granular lymphocytic leukemia that mimicked HSTCL, and a case of aggressive post-transplant lymphoproliferative disorder that developed after chronic EBV infection, suggesting the importance of EBV testing in some lymphoma cases. As the largest cohort of T-cell neoplasms in liver, our study provides critical data on disease frequency, distribution, and clinicopathologic features that are essential for accurate diagnosis.

14.
J Pharm Biomed Anal ; 192: 113651, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33010500

RESUMO

A pure ß-​D-​Glucopyranosiduronic acid metabolite (≥98.0 % purity and a single impurity ≤0.50 %) was requested for biological studies. Due to its unusual instability, the purification of the glucuronide metabolite was extremely challenging. Initially, the crude sample (89 % HPLC area purity) was purified on a Waters SunFire C8 OBD column with 40 mM ammonium acetate buffer and acetonitrile as the mobile phase under a gradient program. The purified glucuronide metabolite solid was obtained by evaporation and lyophilization. However, this procedure yielded the target compound with 97.6 % HPLC area purity and did not meet the requirements. Through the investigation, lyophilization was identified as the key step for the purity of the metabolite, and further lyophilization resulted in an increased amount of the degraded impurities. To better understand the compound, stability studies of the purified metabolite were conducted under sample media, organic solvent, acid, base, and light exposure. The compound was observed to be extremely unstable in water, acid, base and methanol, and sensitive to light, but relatively stable in ammonium acetate buffer (pH 5.0). Taking into account compound stability and the initial purification method, the improved purification procedure was successfully developed and the purified glucuronide metabolite was obtained with 99.2 % HPLC area purity and 0.39 % of the largest single impurity.

15.
Food Chem ; 341(Pt 1): 128241, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33038774

RESUMO

A strategy was developed to distinguish and quantitate nonfumigated ginger (NS-ginger) and sulfur-fumigated ginger (S-ginger), based on Fourier transform near infrared spectroscopy (FT-NIR) and chemometrics. FT-NIR provided a reliable method to qualitatively assess ginger samples and batches of S-ginger (41) and NS-ginger (39) were discriminated using principal component analysis and orthogonal partial least squares discriminant analysis of FT-NIR data. To generate quantitative methods based on partial least squares (PLS) and counter propagation artificial neural network (CP-ANN) from the FT-NIR, major gingerols were quantified using high performance liquid chromatography (HPLC) and the data used as a reference. Finally, PLS and CP-ANN were deployed to predict concentrations of target compounds in S- and NS-ginger. The results indicated that FT-NIR can provide an alternative to HPLC for prediction of active components in ginger samples and was able to work directly on solid samples.

16.
J Biochem Mol Toxicol ; : e22639, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051984

RESUMO

Doxorubicin (DOX) is a very effective broad-spectrum anticancer drug, yet its clinical application is badly restricted due to its serious side effects. Citronellal (CT), a specialized metabolite of plants found in Cymbopogon spp., is proved to exhibit many beneficial properties. In the current study, we intended to investigate the effect of CT on DOX-induced hepatotoxicity in rats. Rats were treated with CT (200 mg/kg b.w./day orally), and given DOX (2.5 mg/kg b.w./week, intraperitoneally) to induce hepatotoxicity for six consecutive weeks. The results showed that CT administration could attenuate the DOX-induced pathological changes of liver tissues and ameliorated the inappropriate alteration of liver function biomarkers (serum glutamic aspartate aminotransferase, glutamic pyruvic transaminase, and albumin) in serum and oxidative stress parameters (malondialdehyde, superoxide dismutase, and reduced glutathione) in the liver. Moreover, CT mitigated the Bax/Bcl-2 ratio and caspase-3 expression to inhibit cell apoptosis. Further study indicated that CT therapy could enhance the protein levels of p-PI3K, p-Akt, and CD31 in the liver. These results demonstrate that CT can ameliorate DOX-induced hepatotoxicity in rats mediated by antioxidative stress, antiapoptosis, and proangiogenesis.

17.
J Med Genet ; 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32900840

RESUMO

BACKGROUND: The genetic causes of human idiopathic non-obstructive azoospermia (NOA) with meiotic arrest remain unclear. METHODS: Two Chinese families with infertility participated in the study. In family 1, two brothers were affected by idiopathic NOA. In family 2, the proband was diagnosed with idiopathic NOA, and his elder sister suffered from infertility. Whole-exome sequencing (WES) was conducted in the two patients in family 1, the proband in family 2 and 362 additional sporadic patients with idiopathic NOA. Sanger sequencing was used to verify the WES results. Periodic acid-Schiff (PAS), immunohistochemistry (IHC) and meiotic chromosomal spread analyses were carried out to evaluate the stage of spermatogenesis arrested in the affected cases. RESULTS: We identified compound heterozygous loss of function (LoF) variants of SHOC1 (c.C1582T:p.R528X and c.231_232del:p.L78Sfs*9, respectively) in both affected cases with NOA from family 1. In family 2, homozygous LoF variant in SHOC1 (c.1194delA:p.L400Cfs*7) was identified in the siblings with infertility. PAS, IHC and meiotic chromosomal spread analyses demonstrated that the spermatogenesis was arrested at zygotene stage in the three patients with NOA. Consistent with the autosomal recessive mode of inheritance, all of these SHOC1 variants were inherited from heterozygous parental carriers. Intriguingly, WES of 362 sporadic NOA cases revealed one additional NOA case with a bi-allelic SHOC1 LoF variant (c.1464delT:p.D489Tfs*13). CONCLUSION: To the best of our knowledge, this is the first report identifying SHOC1 as the causative gene for human NOA. Furthermore, our study showed an autosomal recessive mode of inheritance in the NOA caused by SHOC1 deficiency.

18.
Appl Opt ; 59(24): 7211-7216, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32902484

RESUMO

The polarization ripples on many materials have been intensively studied and have yielded significant applications such as modulating light fields, building hydrophobic or hydrophilic surfaces, and fabricating tunable thermal sources. It was shown that ripples are closely dependent on the ablation threshold of laser fluence and orientation of laser polarization. Here we demonstrate that laser polarization ellipticity also represents the switching effect on the formation of ripples. Two significantly different damage morphologies, ripples and hollows, are respectively observed below and above the switching value of incident laser polarization ellipticity. Furthermore, it is demonstrated that this ellipticity switching value varies with laser pulse energy and pulse number. These intriguing phenomena are qualitatively explained using a laser-surface plasmon polariton interference mechanism. Finally, we achieve the analogous laser-assisted nanopatterning by using a femtosecond laser beam with spatially inhomogeneous polarization state, demonstrating the application potential of these switchable nanoripples in laser-assisted nanopatterning.

19.
Artigo em Inglês | MEDLINE | ID: mdl-32902925

RESUMO

We report here a guest-reaction induced mitosis-like host transformation from a known Pd 4 L 2 cage 1 to a conjoined Pd 6 L 3 twin-cage 2 featuring two separate cavities. The encapsulation of 1-hydroxymethyl-2-naphthol ( G1 ), a known ortho -quinone methide ( o -QMs) precursor, within the hydrophobic cavity of cage 1 is found crucial to realize the cage to twin-cage conversion. Confined G1 molecules within the nanocavity undergo self-coupling dimerization reaction to form 2,2'-dihydroxy-1,1'-dinaphthylmethane ( G2 ) which then triggers the cage to twin-cage mitosis. The same conversion also proceeds, in a much faster rate, via the direct templation of G2 , confirming the induced-fit transformation mechanism. The structure of the 2 ⊃( G2 ) 2 host-guest complex has been established by X-ray crystallographic study, where cis- to trans- conformational switch on one bridging ligand is revealed.

20.
Biomater Sci ; 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32964904

RESUMO

Hemorrhage is the leading cause of preventable death of injured military and civilian patients, and subsequent infection risks endanger their lives or impede the healing of their wounds. Here, we report an injectable biodegradable hydrogel with hemostatic, antimicrobial, and healing-promoting properties. The hydrogel was prepared by dynamic cross-linking of a natural polysaccharide (dextran) with antimicrobial peptide ε-poly-l-lysine (EPL) and encapsulating base fibroblast growth factor (bFGF). The amino groups of EPL were allowed to react with the aldehyde of oxidized dextran (OD) through the Schiff-base reaction for the generation of hydrogels that have fast self-healing and injectable characteristics and adapt to the shapes of wounds. The prepared OD/EPL hydrogels promoted blood clotting in vitro and stopped bleeding in a rat liver injury model within 6 min through their platelet-aggregating ability and sealing effect. These hydrogels exhibited inherent antimicrobial effects without the use of antibiotics and effectively killed a broad spectrum of pathogenic microbes, including Gram-positive methicillin-resistant Staphylococcus aureus (MRSA), Gram-negative Escherichia coli, and Pseudomonas aeruginosa and fungus Candida albicans in vitro. Moreover, these OD/EPL hydrogels were compatible with mammalian cells in vitro and in vivo and biodegradable in the mouse body. The loaded bFGF can be released sustainably, and it can promote angiogenesis, endothelial cell migration, and consequently accelerate the healing of wounds. The OD/EPL hydrogel inhibited MRSA infection in a rat full-thickness skin wound model and promoted healing. This kind of multifunctional hydrogel is a promising wound dressing for the emergency treatment of acute deep or penetrating injuries.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA