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1.
Sci Total Environ ; 713: 136713, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32019046

RESUMO

Laccases have a huge potential in numerous environmental and industrial applications due to the ability to oxidized a wide range of substrates. Here, a novel laccase gene from the identified Bacillus velezensis TCCC 111904 was heterologously expressed in Escherichia coli. The optimal temperature and pH for oxidation by recombinant laccase (rLac) were 80 °C and 5.5, respectively, in the case of the substrate 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and 80 °C and 7.0, respectively, in the case of 2,6-dimethoxyphenol (2,6-DMP). rLac exhibited high thermostability and pH stability over a wide range (pH 3.0, 7.0, and 9.0). Additionally, most of the metal ions did not inhibit the activity of rLac significantly. rLac showed great tolerance against high concentration of NaCl, and 50.8% of its initial activity remained in the reaction system containing 500 mM NaCl compared to the control. Moreover, rLac showed a high efficiency in decolorizing different types of dyes including azo, anthraquinonic, and triphenylmethane dyes at a high temperature (60 °C) and over an extensive pH range (pH 5.5, 7.0, and 9.0). These unique characteristics of rLac indicated that it could be a potential candidate for applications in treatment of dye effluents and other industrial processes.

2.
Dalton Trans ; 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32025689

RESUMO

A nanoscale hybrid material (V2O5-Al13) for highly efficient alcohol oxidation is synthesized through electrostatic self-assembly between oppositely charged Keggin Al13 polyoxocations and exfoliated V2O5 nanosheets. The analyses by X-ray diffraction, electron microscopy, X-ray photoelectron spectroscopy and structural consideration based on charge balance indicate that the Keggin Al13 ions could be sparsely distributed in the nanosheet galleries. The as-prepared catalyst successfully achieved high catalytic activity toward alcohols (96.8% sel.) with the oxygen molecule as an ideal oxidant under mild conditions. Also, the nanohybrid showed an outstanding adsorption capability for benzyl alcohol (773 mg g-1). In comparison to individual exfoliated V2O5 nanosheets and bulk V2O5, the V2O5-Al13 nanohybrid catalyst exhibited superior catalytic activity and selectivity under the same experimental conditions. The results highlight the outstanding functionality of the V2O5-Al13 nanohybrid as an efficient oxidation catalyst. A detailed study of its structure-activity relationship showed that the high performance of the V2O5-Al13 nanohybrid is attributed to the adsorption-catalysis synergistic effect between V2O5 and Al13.

4.
Hepatology ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32003004

RESUMO

While "music has charms to soothe a savage beast", it has no known effect on inactivating hepatic stellate cells (HSC) during fibrosis regression, but the article by Nakano et al. in this issue of Hepatology has identified just such a signal. The success of curative antiviral therapies for hepatitis C virus has revealed the remarkable capacity of hepatic fibrosis to regress spontaneously when injury is attenuated. These clinical observations have validated years of animal studies demonstrating that fibrosis is reversible, however the underlying mechanisms have remained elusive.

5.
Dalton Trans ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32010907

RESUMO

In this study, we report sulfur-doped three-dimensional graphene (S-3DG) as a metal-free electrocatalyst for N2 reduction reaction (NRR) under ambient conditions. Due to the high electron transport capacity and stable physicochemical properties of 3DG, it was utilized to improve the NRR catalytic performance dramatically. Hence, in 0.05 M H2SO4 the S-3DG achieved a remarkably large NH3 yield of 38.81 µgNH3 mgcat-1 h-1 and a high faradaic efficiency of 7.72% at -0.6 V versus a reversible hydrogen electrode (RHE), which is superior to most non-metal catalysts. Notably, it shows such outstanding selectivity that no hydrazine by-products were detected and the electrochemical stability passed a long-term durability test.

6.
Int J Mol Sci ; 21(4)2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32054040

RESUMO

NAC (no apical meristem (NAM), Arabidopsis thaliana transcription activation factor (ATAF1/2) and cup shaped cotyledon (CUC2)) transcription factors play crucial roles in plant development and stress responses. Nevertheless, to date, only a few reports regarding stress-related NAC genes are available in Malus baccata (L.) Borkh. In this study, the transcription factor MbNAC25 in M. baccata was isolated as a member of the plant-specific NAC family that regulates stress responses. Expression of MbNAC25 was induced by abiotic stresses such as drought, cold, high salinity and heat. The ORF of MbNAC25 is 1122 bp, encodes 373 amino acids and subcellular localization showed that MbNAC25 protein was localized in the nucleus. In addition, MbNAC25 was highly expressed in new leaves and stems using real-time PCR. To analyze the function of MbNAC25 in plants, we generated transgenic Arabidopsis plants that overexpressed MbNAC25. Under low-temperature stress (4 °C) and high-salt stress (200 mM NaCl), plants overexpressing MbNAC25 enhanced tolerance against cold and drought salinity conferring a higher survival rate than that of wild-type (WT). Correspondingly, the chlorophyll content, proline content, the activities of antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were significantly increased, while malondialdehyde (MDA) content was lower. These results indicated that the overexpression of MbNAC25 in Arabidopsis plants improved the tolerance to cold and salinity stress via enhanced scavenging capability of reactive oxygen species (ROS).

7.
World J Surg Oncol ; 18(1): 26, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32013978

RESUMO

BACKGROUND: Even with the augmentative application of anal-preservation surgery in low rectal cancer, the role and indications of laparoscopic intersphincteric resection (Lap ISR) are still under debate, especially for T3 or node-positive (T3N0M0, T1-3N+M0) cancer, mainly due to the oncological safety and functional outcomes. INTRABEAM (Carl Zeiss, Germany) intraoperative radiotherapy (IORT) using low-energy X-rays features in accurate irradiation, less exposure, and reduced complications. Taking advantages of Lap ISR and INTRABEAM IORT, this innovative approach aims to increase the probability of the anal preservation with acceptable postoperative outcomes. MATERIALS AND METHODS: From December 2015 to August 2019, we retrospectively analyzed the short-term outcomes of 12 patients evaluated preoperatively with T3 or node-positive (T3N0M0, T1-3N+M0) primary locally advanced low rectal cancer. They all had received Lap ISR and INTRABEAM IORT with a dose of 16-18 Gy applied by an applicator through the anus (natural orifice). Then, with no pre- or postoperative radiotherapy given, the patients were suggested to receive 6-8 cycles of the XELOX chemotherapy regimen (oxaliplatin, 130 mg/m2 and capecitabine, 1000 mg/m2). RESULTS: All patients achieved R0 resection. The median radiation time was 27 min and 15 s, and the mean radiative dose was 17.3 Gy (range 16-18 Gy). The median follow-up time was 18.5 months (range 3-45 months). Two patients experienced local recurrence. Two male patients experienced anastomotic stenosis. Furthermore, one of them experienced perianal abscess and the other one experienced pulmonary metastasis after refusing to receive chemotherapy. One female patient with internal anal sphincter invasion experienced distant metastases to the liver and gluteus maximus muscle 35 months after IORT. No acute radiation injuries or symptoms were observed. Although they experienced a reduction in anal function, every patient was satisfied with the postoperative outcomes. CONCLUSIONS: For patients evaluated preoperatively with T3 or node-positive (T3N0M0, T1-3N+M0) primary locally advanced low rectal cancer, Lap ISR with INTRABEAM IORT may be a safe and feasible approach for anal preservation without compromising oncological outcomes.

8.
BMC Infect Dis ; 20(1): 126, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32046674

RESUMO

BACKGROUND: More and more azole-resistant strains emerged through the development of acquired resistance and an epidemiological shift towards inherently less susceptible species. The mechanisms of azoles resistance of Candida albicans is very complicated. In this study, we aim to investigate the mechanism of azole-resistant C. albicans isolated from the oral cavity of a patient with chronic mucocutaneous candidiasis (CMC). CASE PRESENTATION: CMC diagnosis was given based on clinical manifestations, laboratory test findings and gene sequencing technique. Minimum inhibitory concentration (MIC) of the fungal isolate, obtained from oral cavity termed as CA-R, was obtained by in vitro anti-fungal drugs susceptibility test. To further investigate the resistant mechanisms, we verified the mutations of drug target genes (i.e. ERG11 and ERG3) by Sanger sequencing, and verified the over-expression of ERG11 and drug efflux genes (i.e. CDR1 and CDR2) by RT-PCR. A heterozygous mutation of c.1162A > G resulting in p.K388E was detected in STAT1 of the patient. The expression of CDR1 and CDR2 in CA-R was 4.28-fold and 5.25-fold higher than that of type strain SC5314, respectively. CONCLUSIONS: Up-regulation of CDR1 and CDR2 was mainly responsible for the resistance of CA-R. For CMC or other immunodeficiency patients, drug resistance monitoring is necessary.

9.
J Biol Chem ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32047109

RESUMO

Oxidative stress-induced DNA damage, the senescence-associated secretory phenotype (SASP), and impaired autophagy all are general features of senescent cells. However, the crosstalk among these events and processes is not fully understood. Here, using NIH3T3 cells exposed to hydrogen peroxide stress, we show that stress-induced DNA damage provokes the SASP largely via cytosolic chromatin fragment (CCF) formation, which activates a cascade comprising cGMP-AMP synthase (cGAS), stimulator of interferon genes protein (STING), NF-κB, and SASP, and that autolysosomal function inhibits this cascade. We found that CCFs accumulate in senescent cells with activated cGAS-STING-NF-κB signaling, promoting SASP and cellular senescence. We also present evidence that the persistent accumulation of CCFs in prematurely senescent cells is partially associated with a defect in DNA- degrading activity in autolysosomes and reduced abundance of activated DNase 2a. Intriguingly, we found that metformin- or rapamycin-induced activation of autophagy significantly lessened the size and levels of CCFs and repressed the activation of the cGAS-STING-NF-κB-SASP cascade and cellular senescence. These effects of autophagy activators indicated that autolysosomal function contributes to CCFs clearance and SASP suppression, further supported by the fact that the lysosome inhibitor bafilomycin A1 blocked the role of autophagy-mediated CCFs clearance and senescence repression. Taken together, these findings confirm the significant role of CCFs formation in the SASP and oxidative stress-induced senescence and reveal that CCF-mediated SASP inversely correlated with autolysosomal function. We conclude that the restoration of autolysosomal function may prevent DNA damage-provoked SASP production and cellular senescence.

10.
J Exp Clin Cancer Res ; 39(1): 1, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31928527

RESUMO

BACKGROUND: Circular RNAs (circRNAs) have recently emerged as a new family of noncoding RNAs that are involved in the causation and progression of various cancers. However, the roles of circRNAs in the tumorigenesis of gastric cancer (GC) are still largely unknown. METHODS: The expression profiles of circRNAs in GC were identified in open GEO database and were evaluated at the mRNA level in clinical GC samples compared with paired non-tumorous tissues. Kaplan-Meier survival curve was used to analyze the correlation of circRNA and patients' prognosis. Subsequently, the circular structures of candidate circRNAs were validated by Sanger sequencing, divergent primer PCR, and RNase R treatments. Gain- and loss-of-function analyses were performed to evaluate the functional significance of it in GC initiation and progression. Dual-luciferase reporter and RNA pull-down assays were used to identify the microRNA (miRNA) sponge mechanism of circRNAs. RESULTS: The expression of circRHOBTB3 was lower in GC tissues and cell lines. Downregulation of circRHOBTB3 was significantly correlated with poor differentiation and unfavorable prognosis in patients with GC. Overexpression of circRHOBTB3 in GC cells led to decreased proliferation and induced G1/S arrest in vitro, accompanied with inhibited xenograft tumor growth in vivo, while the opposite effects were achieved in circRHOBTB3-silenced cells. Furthermore, we demonstrated that circRHOBTB3 acts as a sponge for miR-654-3p and verified that p21 is a novel target of miR-654-3p. CONCLUSION: Taken together, this study revealed that circRHOBTB3 might function as competing endogenous RNA (ceRNA) for miR-654-3p, which could contribute to growth inhibition of GC through activating p21 signaling pathway. Our data suggested that circRHOBTB3 would serve as a novel promising diagnosis marker and therapeutic target for GC.

11.
Orthop Surg ; 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31944618

RESUMO

OBJECTIVE: To compare the ability of three culture strategies of static culture, intermittent centrifugal culture and dynamic bioreactor culture in promoting the infiltration of bone marrow mesenchymal stem cells (BMSCs) throughout electrospun nanoporous aligned nanoyarn scaffold (AYS). METHODS: AYS was constructed by the method of conjugated electrospinning, using the blended solution of poly (L-lactide-co-caprolactone) (P (LLA-CL)) and gelatin. Then the bone marrow mesenchymal stem cells (BMSCs) were transplanted on the scaffolds. Culture the scaffold-cells using three methods of static culture, intermittent centrifugal culture and dynamic bioreactor culture. After 7 and 14 days in culture, the infiltration depth of the cells were observed and measured by hematoxylin and eosin (HE) or 4', 6-diamidino-2-phenylindole (DAPI) staining. RESULT: In the current study, on the 7th day, the BMSCs in the scaffolds of static culture group, intermittent centrifugal culture group, and dynamic bioreactor culture group infiltrated to an average depth of 11.88 ± 1.82 µm, 21.17 ± 13.17 µm, and 26.27 ± 7.42 µm, respectively. There were differences between the bioreactor culture group with the static culture group and the intermittent centrifugal culture group. On the time point of 14 days, the depth of infiltration of BMSCs in dynamic bioreactor culture was the most (115.13 ± 25.44 µm, P < 0.05), and the infiltration of the cells in the intermittent centrifugal culture group was 42.53 ± 13.07 µm, deeper than that of the static culture group (24.53 ± 6.06, P < 0.05). CONCLUSION: Dynamic bioreactor culture may be a preferred method for tissue engineering approaches involving scaffolds with a low porosity, such as those needed for repair of the annulus fibrosus (AF).

12.
J Cell Mol Med ; 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31970902

RESUMO

Macrophage activation participates in the pathogenesis of pulmonary inflammation. As a coenzyme, vitamin B6 (VitB6) is mainly involved in the metabolism of amino acids, nucleic acids, glycogen and lipids. We have previously reported that activation of AMP-activated protein kinase (AMPK) produces anti-inflammatory effects both in vitro and in vivo. Whether VitB6 via AMPK activation prevents pulmonary inflammation remains unknown. The model of acute pneumonia was induced by injecting mice with lipopolysaccharide (LPS). The inflammation was determined by measuring the levels of interleukin-1 beta (IL-1ß), IL-6 and tumour necrosis factor alpha (TNF-α) using real time PCR, ELISA and immunohistochemistry. Exposure of cultured primary macrophages to VitB6 increased AMP-activated protein kinase (AMPK) Thr172 phosphorylation in a time/dose-dependent manner, which was inhibited by compound C. VitB6 downregulated the inflammatory gene expressions including IL-1ß, IL-6 and TNF-α in macrophages challenged with LPS. These effects of VitB6 were mirrored by AMPK activator 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR). However, VitB6 was unable to inhibit LPS-induced macrophage activation if AMPK was in deficient through siRNA-mediated approaches. Further, the anti-inflammatory effects produced by VitB6 or AICAR in LPS-treated macrophages were abolished in DOK3 gene knockout (DOK3-/- ) macrophages, but were enhanced in macrophages if DOK3 was overexpressed. In vivo studies indicated that administration of VitB6 remarkably inhibited LPS-induced both systemic inflammation and acute pneumonia in wild-type mice, but not in DOK3-/- mice. VitB6 prevents LPS-induced acute pulmonary inflammation in mice via the inhibition of macrophage activation.

13.
Head Neck ; 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31981257

RESUMO

BACKGROUND: For early-stage oral squamous cell carcinoma (OSCC), there is no existing risk-stratification modality beyond conventional TNM staging system to identify patients at high risk for cancer-specific mortality. METHODS: A total of 568 early-stage OSCC patients who had surgery only and also with available 5-year clinical outcomes data were identified. Signature microRNAs (miRNAs) were discovered using deep sequencing analysis and validated by qRT-PCR. The final 5-plex prognostic marker panel was utilized to generate a cancer-specific mortality risk score using the multivariate Cox regression analyses. The prognostic markers were validated in the internal and external validation cohorts. RESULTS: The risk score from the 5-plex marker panel consisting of miRNAs-127-3p, 4736, 655-3p, TNM stage and histologic grading stratified patients into four risk categories. Compared to the low-risk group, the high-risk group had 23-fold increased mortality risk (hazard ratio 23, 95% confidence interval 13-42), with a median time-to-recurrence of 6 months and time-to-death of 11 months (vs >60 months for each among low-risk patient; p < .001). CONCLUSION: The miRNA-based 5-plex marker panel driven mortality risk score formula provides clinically practical and reliable measures to assess the prognosis of patients assigned to an early-stage OSCC.

14.
Scand J Immunol ; : e12867, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31975405

RESUMO

Hesperetin (HES) is a dihydroflavone with the molecular formula of C16H14O6. It has been reported that Hesperetin has antioxidant and anticancer effects. Recent studies showed that it can also regulate immune responses. To assess its potential function as a vaccine adjuvant, we formulated HES with inactivated B16F10 melanoma cells and determined whether it would enhance the activation of antigen-presenting cells by experiments in vivo and in vitro. We found that HES activated the PI3K-Akt signalling pathway in antigen-presenting cells (APCs), enhanced cytotoxic T lymphocyte (CTL) responses and deactivated tolerogenic T cells. We also observed that inactivated B16F10 cells in combination with HES vaccine inhibited the growth of mice tumours, resulting in improved overall survival compared to the effects of inactivated B16F10 cell vaccine. To verify that CD8+ T cells play a key role in inhibiting the development of melanoma, we transferred the sorted CD8+ T cells from immunized mice to B16F10 challenged models and found that the survival rate of tumour-bearing mice was significantly prolonged. Taken together, these results suggest that hesperetin can be used as a potential adjuvant to improve tumour immune responses and antigen immunogenicity.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31901181

RESUMO

Purely organic materials showing room temperature phosphorescence (RTP) and ultralong RTP (OURTP) have recently attracted much attention. However, it is challenging to integrate circularly polarized luminescence (CPL) into RTP/OURTP. Here, we show a strategy to realize CPL-active OURTP (CP-OURTP) by binding an achiral phosphor group directly to the chiral center of an ester chain. Engineering of this flexible chiral chain enables efficient chirality transfer to carbazole aggregates, resulting in strong CP-OURTP with a lifetime of over 0.6 s and dissymmetry factor of 2.3×10-3 after the conformation regulation upon photo-activation. The realized CP-OURTP is thus stable at room temperature but can be deactivated quickly at 50 °C to CP-RTP with high CPL stability during the photo-activation/thermal-deactivation cycles. Based on this extraordinary photo/thermal-responsive and highly reversible CP-OURTP/RTP, a CPL-featured lifetime-encrypted combinational logic device has been successfully established.

16.
Methods Mol Biol ; 2117: 109-131, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31960375

RESUMO

Identifying epigenetic field defects, notably early DNA methylation alterations, is important for early cancer detection. Research has suggested these early methylation alterations are infrequent across samples and identifiable as outlier samples. Here we developed a weighted epigenetic distance-based method characterizing (dis)similarity in methylation measures at multiple CpGs in a gene or a genetic region between pairwise samples, with weights to up-weight signal CpGs and down-weight noise CpGs. Using distance-based approaches, weak signals that might be filtered out in a CpG site-level analysis could be accumulated and therefore boost the overall study power. In constructing epigenetic distances, we considered both differential methylation (DM) and differential variability (DV) signals. We demonstrated the superior performance of the proposed weighted epigenetic distance-based method over nonweighted versions and site-level EWAS (epigenome-wide association studies) methods in simulation studies. Application to breast cancer methylation data from Gene Expression Omnibus (GEO) comparing normal-adjacent tissue to tumor of breast cancer patients and normal tissue of independent age-matched cancer-free women identified novel epigenetic field defects that were missed by EWAS methods, when majority were previously reported to be associated with breast cancer and were confirmed the progression to breast cancer. We further replicated some of the identified epigenetic field defects.

17.
Medicine (Baltimore) ; 99(1): e16791, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31895764

RESUMO

The present study aimed to investigate the feasibility of vaginal delivery combined with vaginal tightening surgery and perineal body repair.From January 2017 to April 2017, 5 cases underwent vaginal delivery combined with vaginal tightening surgery and perineal body repair. We retrospectively analyzed the clinical data.The incisions of 5 cases were all primary healing; vulva form was improved, and there were no postoperative hematoma, infection or vaginal mucosa prolapse. Sexual function was improved to different degrees. The pelvic muscle force test showed that both the type I and type II myofiber scores were increased.It is feasible to perform vaginal delivery combined with vaginal tightening surgery and perineal body repair, which is a safe and effective method for improving sex life and pelvic floor function.


Assuntos
Parto Obstétrico/efeitos adversos , Vagina/cirurgia , Adulto , Feminino , Humanos , Lacerações/etiologia , Lacerações/cirurgia , Diafragma da Pelve/fisiopatologia , Diafragma da Pelve/cirurgia , Períneo/lesões , Períneo/cirurgia , Gravidez , Qualidade de Vida , Vagina/fisiopatologia , Vulva/cirurgia
18.
Carbohydr Polym ; 230: 115665, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887949

RESUMO

Electrospinning of pure alginate or derivatives has always been a pursuing goal in biological fields in recent years owing to its fascinating biological characteristics and biomimetic structures. Yet it is still a severe challenge in view of its insufficient entanglements and strong electrostatic repulsions. Herein, alginate dialdehyde (ADA) with improved and adjustable chain flexibility was prepared via periodate-oxidation. Chain flexibility, concentration, ethanol and crosslinkers played key roles in electrospinning proved by persistence length (lp), the number of entanglement points (ne) and fiber morphology. Finally, insoluble ADA corsslinked nanofiber membranes were obtained, which exhibited excellent mechanical properties and adjustable degradability. Specially, biocompatibility assays confirmed that the preparing membranes were noncytotoxic, and could promote cell attachment and proliferation. Therefore, under the guidance of the relationship between chain flexibility and electrospinnability, pure alginate-based nanofiber membranes are expected to become promising scaffolds for biomedical applications, particularly for wound healing which demanding appropriate degradation.

19.
Analyst ; 145(2): 626-635, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31782420

RESUMO

As a highly invasive and the most prevalent malignancy, lung cancer remains the leading cause of cancer-associated mortality worldwide, especially in China. Microwave ablation (MWA) is an effective, safe, and the least invasive ablative treatment modality, which has been increasingly used for the management of unrespectable lung tumors. However, the underlying biochemical mechanisms of MWA treatment remain to be incompletely elucidated. Therefore, to illustrate the complex biochemical responses of lung squamous cell carcinoma (LSCC) to MWA treatment, confocal Raman micro-spectral imaging (CRMI) was applied in combination with multivariate analysis. A total of twelve LSCC tissues were acquired from patients undergoing clinical treatment, and their spectral characteristics were analyzed to determine significant spectral variations following cancer progression and MWA treatment in comparison with healthy lung tissues. Point-scanned Raman datasets were acquired from sectioned tissue samples in both pre-therapy (Pre-MWA group) and post-therapy groups (Post-MWA group) and further analyzed using K-means cluster analysis (KCA) and principal component analysis (PCA) to highlight the detailed compositional variations of the biochemical constituents. The spectral variations of essential amino acids (such as phenylalanine and tryptophan), collagen, and nucleic acids in the cancerous tissues of the Post-MWA group were significantly enhanced compared to those in the Pre-MWA group. The acquired information further confirmed a remarkable increase in the content of nucleic acid, protein, and lipid in the cancerous tissue following MWA treatment and, a comparative spectral imaging investigation indicated that MWA had no noticeable adverse effects on the paracancerous tissues. Thus, the findings not only illustrated the underlying biochemical variability in lung cancer during MWA treatment but also further confirmed the feasibility of a combined analytical procedure for assessing the biochemical responses during thermal ablation, which could be applied to prominently enhance the effectiveness of MWA in lung cancer treatment in clinical settings.

20.
Diabetes ; 69(2): 205-214, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31806625

RESUMO

A sufficient ß-cell mass is crucial for preventing diabetes, and perinatal ß-cell proliferation is important in determining the adult ß-cell mass. However, it is not yet known how perinatal ß-cell proliferation is regulated. Here, we report that serotonin regulates ß-cell proliferation through serotonin receptor 2B (HTR2B) in an autocrine/paracrine manner during the perinatal period. In ß-cell-specific Tph1 knockout (Tph1 ßKO) mice, perinatal ß-cell proliferation was reduced along with the loss of serotonin production in ß-cells. Adult Tph1 ßKO mice exhibited glucose intolerance with decreased ß-cell mass. Disruption of Htr2b in ß-cells also resulted in decreased perinatal ß-cell proliferation and glucose intolerance in adulthood. Growth hormone (GH) was found to induce serotonin production in ß-cells through activation of STAT5 during the perinatal period. Thus, our results indicate that GH-GH receptor-STAT5-serotonin-HTR2B signaling plays a critical role in determining the ß-cell mass by regulating perinatal ß-cell proliferation, and defects in this pathway affect metabolic phenotypes in adults.

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