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1.
J Asian Nat Prod Res ; : 1-7, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34647847

RESUMO

Quercetin (1) was converted into quercetin 7-O-succinyl glucoside (2) by used Bacillus amyloliquefaciens FJ18 as a solvent-resistant whole-cell biocatalyst. The structure of the new compound was confirmed by LC-MS analysis and NMR spectroscopy. The water-solubility of this novel quercetin 7-O-succinyl glucoside (2) was approximately 1000 times higher than that of native quercetin (2). Quercetin (1) and quercetin 7-O-succinyl glucoside (2) exhibited significant DPPH scavenging capacity with IC50 values of 23.55 and 36.05 µM, respectively. Both compounds showed moderate cytotoxic effects against the two human cancer cell lines (MCF-7 and HepG2) with IC50 values ranging from 39.45-63.38 µM.

2.
Hepatology ; 2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34687050

RESUMO

BACKGROUND & AIMS: The mechanisms involved in liver regeneration after partial hepatectomy (PHx) are complicated. Cellular senescence, once linked to aging, plays a pivotal role in wound repair. However, the regulatory effects of cellular senescence on liver regeneration have not been fully elucidated. APPROACH & RESULTS: Mice subjected to PHx were analyzed 14 days after surgery. The incomplete remodeling of liver sinusoids affected shear stress-induced eNOS signaling on day 14, resulting in the accumulation of senescent liver sinusoidal endothelial cells (LSECs). Removing macrophages to augment LSEC senescence led to a malfunction of the regenerating liver. A dynamic fluctuation in Notch activity accompanied senescent LSEC accumulation during liver regeneration. Endothelial Notch activation by using Cdh5-CreERT NICeCA mice triggered LSEC senescence and senescence-associated secretory phenotype (SASP), which disrupted liver regeneration. Blocking the Notch by γ-secretase inhibitor (GSI) diminished senescence and promoted LSEC expansion. Mechanically, Notch-Hes1 signaling inhibited Sirt1 transcription by binding to its promoter region. Activation of Sirt1 by SRT1720 neutralized the up-regulation of P53, P21, and P16 caused by Notch activation, and eliminated Notch-driven LSEC senescence. Finally, Sirt1 activator promoted liver regeneration by abrogating LSEC senescence and improving sinusoid remodeling. CONCLUSIONS: Shear stress-induced LSEC senescence driven by Notch interferes with liver regeneration after PHx. Sirt1 inhibition accelerates liver regeneration by abrogating Notch-driven senescence, providing a potential opportunity to target senescent cells and facilitate liver repair after injury.

3.
Biomedicines ; 9(9)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34572398

RESUMO

Remote ischemic conditioning (RIC) is a procedure that can attenuate ischemic-reperfusion injury by conducting brief cycles of ischemia and reperfusion in the arm or leg. Extracellular vesicles (EVs) circulating in the bloodstream can release their content into recipient cells to confer protective function on ischemia-reperfusion injured (IRI) organs. Skeletal muscle cells are potential candidates to release EVs as a protective signal during RIC. In this study, we used C2C12 cells as a model system and performed cyclic hypoxia-reoxygenation (HR) to mimic RIC. EVs were collected and subjected to small RNA profiling and proteomics. HR induced a distinct shift in the miRNA profile and protein content in EVs. HR EV treatment restored cell viability, dampened inflammation, and enhanced tube formation in in vitro assays. In vivo, HR EVs showed increased accumulation in the ischemic brain compared to EVs secreted from normoxic culture (N EVs) in a mouse undergoing transient middle cerebral artery occlusion (tMCAO). We conclude that HR conditioning changes the miRNA and protein profile in EVs released by C2C12 cells and enhances the protective signal in the EVs to recipient cells in vitro.

4.
Molecules ; 26(17)2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34500653

RESUMO

Davidone C is a newly discovered flavonoid compound purified from the ethyl acetate-soluble fraction of Sophora davidii (Franch.) Skeels. This study explored the anti-tumor activity of davidone C on hepatocellular carcinoma HepG2 and Bel-7402 cells and its mechanism through MTT method, morphological observation, flow cytometry and Western blotting. The results showed that davidone C significantly inhibited the proliferation of HepG2 and Bel-7402 cells in a time- and dose-dependent manner. The morphological changes of apoptotic cells can be observed under an inverted microscope, such as cell floating, chromosome condensation, apoptotic bodies, and other phenomena. The expressions of Bax, cleaved caspase-9, cleaved caspase-3 and cleaved PARP increased with the increase of dosage while Bcl-2 decreased, suggesting that the apoptotic mechanism might be related to the mitochondrial apoptotic pathway. Moreover, davidone C administration can down-regulate the expression of Grp78, and simultaneously up-regulate the expression of caspase-7 and caspase-12, indicating that the apoptotic mechanism might be related to the ERS pathway. In addition, davidone C can down-regulate the expression of p62, and simultaneously up-regulate the expression of LC3-I and LC3-II with a quantitative dependence, suggesting that the mechanism of apoptosis may be related to the autophagy signal pathway. All these results showed davidone C has potential effects on hepatocellular carcinoma.

5.
Planta ; 254(4): 69, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34498125

RESUMO

MAIN CONCLUSION: Indole 3-hexanoic acid is a novel auxin and regulates plant growth and development. Auxin is a signaling molecule that influences most aspects of plant development. Although many small bioactive molecules have been developed as auxin analogues, naturally occurring auxin and the detailed mechanisms of its specific actions in plants remain to be fully elucidated. In this study, to screen auxin responses, we used a novel picolinate synthetic auxin, 3-indole hexanoic acid (IHA), which is similar in structure to indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA). IHA showed classical auxin activity in the regulation of root growth, gene expression, and PIN-FORMED abundance. Physiological and genetic analyses indicated that IHA may be perceived by the auxin receptor TIR1 and transported by the G-class ATP-binding cassette protein ABCG36 and its homolog ABCG37. Importantly, IHA was detected in planta and converted into IBA depending on the peroxisomal ß-oxidation. Together, these findings reveal a novel auxin pathway component and suggest possible undiscovered modes of auxin metabolism regulation in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Caproatos , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Indóis , Raízes de Plantas/metabolismo
6.
Appl Microbiol Biotechnol ; 105(18): 6707-6718, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34476516

RESUMO

Pneumocandin B0, the precursor of the antifungal drug caspofungin, is a lipohexapeptide produced by the fungus Glarea lozoyensis. Oxidative stress and the resulting production of reactive oxygen species (ROS) are known to be involved in the regulation of pneumocandin B0 biosynthesis. In this study, the Glyap1 gene of Glarea lozoyensis, a homologue of the yeast redox regulator YAP1, was knocked out. The intracellular ROS levels of the resulting ΔGlyap1 strain were higher than in the wild-type strain, which was caused by the downregulated expression of superoxide dismutase (SOD) and catalase (CAT). Compared with the wild-type strain, ΔGlyap1 exhibited an oxidative phenotype throughout its life cycle, which resulted in significantly higher pneumocandin B0 production per unit biomass. In addition, ΔGlyap1 showed growth inhibition and decreased pneumocandin B0 production in the presence of CCl4, which leads to strong oxidative stress. To overcome the strain's sensitivity, a three-stage antioxidant addition strategy was developed. This approach significantly improved the growth of ΔGlyap1 while maintaining a high pneumocandin B0 production per unit biomass, which reached 38.78 mg/g DCW. Notably, this result represents a 50% increase over the wild-type strain. These findings provide new insights into the regulatory mechanisms that control pneumocandin B0 production under oxidative stress, which may be applied to improve the production of other secondary metabolites. KEY POINTS: • Glyap1 is involved in expression of redox and pneumocandin B0 synthesis-related genes. • Addition of a three-stage antioxidant alleviated the sensitivity of ΔGlyap1 strain. • The yield of pneumocandin B0 per unit biomass of ΔGlyap1 strain was 38.78 mg/g DCW.


Assuntos
Ascomicetos , Equinocandinas , Ascomicetos/genética , Ascomicetos/metabolismo , Equinocandinas/metabolismo , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio
7.
Genome Biol ; 22(1): 227, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34482832

RESUMO

We develop the Oncogene Concatenated Enriched Amplicon Nanopore Sequencing (OCEANS) method, in which variants with low variant allele frequency (VAFs) are amplified and subsequently concatenated for Nanopore Sequencing. OCEANS allows accurate detection of somatic mutations with VAF limits of detection between 0.05 and 1%. We construct 4 distinct multi-gene OCEANS panels targeting recurrent mutations in acute myeloid leukemia, melanoma, non-small- cell lung cancer, and hepatocellular carcinoma and validate them on clinical samples. By demonstrating detection of low VAF single nucleotide variant mutations using Nanopore Sequencing, OCEANS is poised to enable same-day clinical sequencing panels.

8.
Theranostics ; 11(17): 8464-8479, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34373753

RESUMO

As glutamine plays a central role in cancer metabolism, inhibition of glutaminolysis has become an ideal anticancer therapeutic target. However, glutaminolysis inhibition leads to activation of autophagy, which compromises its antitumor effect. Hence, we investigated the mechanism underlying glutaminolysis inhibition-induced pro-survival autophagy. Methods: High-throughput sequencing was performed on colorectal cancer (CRC) cells before and after glutaminolysis inhibition to identify differentially expressed genes. Activating transcription factor 4 (ATF4) pathway enrichment in glutaminolysis inhibited cells was identified through gene set enrichment analysis. ATF4 expression was assessed by quantitative real-time PCR (qRT-PCR) and western blotting. The function of ATF4 on mechanistic target of rapamycin (mTOR) regulation was assessed by western blotting. Luciferase reporter assays and chromatin immunoprecipitation were used to confirm the regulation of DNA damage inducible transcript 4 (DDIT4) by ATF4. mRNA half-life assays, RNA immunoprecipitation, qRT-PCR and western blotting were performed to determine the relationship between FTO alpha-ketoglutarate dependent dioxygenase (FTO), YTH N6-methyladenosine RNA binding protein 2 (YTHDF2), and ATF4. ATF4 regulation of pro-survival autophagy was measured by tandem monomeric red fluorescent protein-green fluorescent protein fluorescence microscopy. Finally, the synergistic effect of autophagy and glutaminolysis inhibition was analyzed in an azoxymethane/dextran sodium sulfate mouse model. Results: The ATF4 pathway was activated in CRC cells upon glutaminolysis inhibition. Functionally, ATF4 transcriptionally upregulated DDIT4 to suppress mTOR, which induced pro-survival autophagy during glutaminolysis inhibition. Interestingly, glutaminolysis inhibition promoted ATF4 mRNA expression by abrogating N6-methyladenosine (m6A) modification and YTHDF2-mediated RNA decay. Finally, inhibition of ATF4-induced autophagy enhanced the antitumor efficacy of glutaminolysis inhibition. Conclusion: Glutaminolysis inhibition upregulated ATF4 expression in an m6A-dependent manner to activate pro-survival autophagy through transcriptional activation of the mTOR inhibitor DDIT4. Targeting ATF4-induced autophagy is a new strategy to synergize glutaminolysis-targeting therapies for cancer treatment.

9.
Int J Mol Sci ; 22(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361033

RESUMO

Apolipoprotein E (ApoE), an essential plasma apolipoprotein, has three isoforms (E2, E3, and E4) in humans. E2 is associated with type III hyperlipoproteinemia. E4 is the major susceptibility gene to Alzheimer's disease (AD) and coronary heart disease (CHD). We investigated lipid metabolism and atherosclerotic lesions of novel humanized ApoE knockin (hApoE KI) rats in comparison to wide-type (WT) and ApoE knockout (ApoE KO) rats. The hApoE2 rats showed the lowest bodyweight and white fat mass. hApoE2 rats developed higher serum total cholesterol (TC), total triglyceride (TG), and low- and very low density lipoprotein (LDL-C&VLDL-C). ApoE KO rats also exhibited elevated TC and LDL-C&VLDL-C. Only mild atherosclerotic lesions were detected in hApoE2 and ApoE KO aortic roots. Half of the hApoE2 rats developed hepatic nodular cirrhosis. A short period of the Paigen diet (PD) treatment led to the premature death of the hApoE2 and ApoE KO rats. Severe vascular wall thickening of the coronary and pulmonary arteries was observed in 4-month PD-treated hApoE4 rats. In conclusion, hApoE2 rats develop spontaneous hyperlipidemia and might be suitable for studies of lipid metabolism-related diseases. With the PD challenge, hApoE4 KI rats could be a novel model for the analysis of vascular remodeling.


Assuntos
Apolipoproteínas E/genética , Aterosclerose/genética , Hiperlipidemias/genética , Metabolismo dos Lipídeos , Cirrose Hepática/genética , Animais , Apolipoproteínas E/metabolismo , Colesterol/sangue , Vasos Coronários/metabolismo , Vasos Coronários/patologia , Técnicas de Introdução de Genes , Humanos , Lipoproteínas LDL/sangue , Masculino , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Ratos , Ratos Sprague-Dawley , Triglicerídeos/sangue , Remodelação Vascular
10.
Acta Biochim Biophys Sin (Shanghai) ; 53(10): 1310-1320, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34409427

RESUMO

Endothelial dysfunction is the pathological basis of atherosclerosis. Incomplete understanding of endothelial dysfunction etiology has impeded drug development for this devastating disease despite the currently available therapies. Floralozone, an aroma flavor, specifically exists in rabbit ear grass. Recently, floralozone has been demonstrated to inhibit atherosclerosis, but the underlying mechanisms are undefined. The present study was undertaken to explore whether floralozone pharmacologically targets endothelial dysfunction and therefore exerts therapeutic effects on atherosclerosis. The Na+/H+ exchanger 1 (NHE1), a channel protein, plays a vital role in atherosclerosis. Whether NHE1 is involved in the therapeutic effects of floralozone on endothelial dysfunction has yet to be further answered. By performing oil red staining and hematoxylin-eosin staining, vascular functional study, and oxidative stress monitoring, we found that floralozone not only reduced the size of carotid atherosclerotic plaque but also prevented endothelial dysfunction in atherosclerotic rats. NHE1 expression was upregulated in the inner membrane of carotid arteries and H2O2-induced primary rat aortic endothelial cells. Inspiringly, floralozone prevented the upregulation of NHE1 in vivo and in vitro. Notably, the administration of NHE1 activator LiCl significantly weakened the protective effect of floralozone on endothelial dysfunction in vivo and in vitro. Our study demonstrated that floralozone exerted its protective effect on endothelial dysfunction in atherosclerosis by ameliorating NHE1. NHE1 maybe a drug target for the treatment of atherosclerosis, and floralozone may be an effective drug to meet the urgent needs of atherosclerosis patients by dampening NHE1.

11.
Anal Bioanal Chem ; 413(26): 6595-6603, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34430983

RESUMO

A simple and low-cost fluorescence aptasensor was developed for rapid and sensitive signal amplification detection of T-2 mycotoxin (T-2). Dual-terminal-fluorescein amidite (FAM)-labeled aptamer (D-aptamer) acted as a recognition element and signal indicator. The metal organic frameworks (MOFs) of N, N'-bis(2-hydroxyethyl)dithiooxamidato copper (II) (H2dtoaCu) were as the quencher. The D-aptamer was initially adsorbed to the surface of H2dtoaCu, leading to efficient quenching of the aptasensor. Upon addition of T-2, the D-aptamer underwent a conformation change to form the T-2/T-2 aptamer complex, which induced the signaling probe to be released from the H2dtoaCu surface. Thus, the fluorescence intensity (FL) of the D-aptamer was recovered. Versus the single-terminal-FAM-labeled aptamer (S-aptamer), the D-aptamer showed a lower detection limit of 0.39 ng/mL. The aptasensor was also successfully applied to detect T-2 in corn and wheat samples with good recoveries.

12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(4): 1093-1100, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34362487

RESUMO

OBJECTIVE: To investigate the clinicopathologic characteristics, diagnosis and therapy of aggressive natural killer cell leukemia (ANKL) patients. METHODS: Clinical manifestations, cellular morphology, immunophenotypic analysis by flow cytometry (FCM), TCR gene rearrangement, pathology and Immunohistochemical analysis of bone marrow (BM) were combined to diagnose the six patients with ANKL. RESULTS: The median age of the patients were 35.5 years old. All the patients with fever, cytopenia and liver dysfunction. Imageological examination presented hepatosplenomegaly (6/6), and PET/CT presented diffusely increased metabolism in liver, spleen and BM (3/3). BM cytologic examination presented increased hematophagocyte at the early stage and 1%-42% leukemic cell were detected in BM with the progression of diseases. FCM showed the leukemic cells were positive for CD2(6/6), CD56(5/6), CD16(2/6), CD94(3/6), CD38(3/6), cCD3(1/5), CD8(1/6), CD7(2/6), CD57(1/6) and negative for CD3, CD4, TdT, cMPO, TCR α/ß, TCR γ/δ. The neoplastic cells were negative for TCR gene rearrangement. Five cases showed increased quantitation of whole blood Epstein-Barr virus (EBV) DNA. CONCLUSION: ANKL is a highly aggressive disease. Prompt and repeating BM examination is important to patient with fever, cytopenia and liver dysfunction. The diagnosis of ANKL relies mainly on the integration of clinical, morphologic, immunophenotypic finding and EBV-DNA increasement.


Assuntos
Infecções por Vírus Epstein-Barr , Leucemia Linfocítica Granular Grande , Adulto , Herpesvirus Humano 4 , Humanos , Imunofenotipagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
13.
Nanotechnology ; 32(45)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34352731

RESUMO

Ruthenium(II) polypyridyl complexes (Ru) show high anti-tumor activity, but their poor solubility and low biocompatibility impede their use in anti-tumor therapy. Here,we circumvented the problem of low solubility by encapsulating the Ru in thermosensitive liposomes (LTSLs) and used gold nanorods (Au NRs) modified on the surface of the liposomes to permit the precise release of Ru at the tumor site. A facile and simple method was developed to synthesize Ru-loaded Au NR-decorated LTSL (Au@LTSL-Ru NPs). The loaded Au NRs improved the anti-tumor effect of Ru and enhanced the photothermal therapeutic properties of the nanosystem. A characterization experiment indicated that the average particle size of Au@LTSL-Ru was approximately 300 nm and that the Au NRs were successfully modified on the surface of LTSL. In thein vitroanti-tumor test, Au@LTSL-Ru and NIR significantly inhibited the proliferation of SGC-7901 cells. The IC50value of Au@LTSL-Ru + NIR was 7.1 ± 1.2µM (13µg ml-1), and the inhibition rate was greater than 90% when the concentration reached 30µg ml-1.In vivostudies revealed that Au@LTSL-Ru and NIR had a significant inhibitory effect on subcutaneous tumor tissues derived from SGC-7901 cells. Analysis of histopathology and immunocytotoxicity indicated that Au@LTSL-Ru has fewer side effects and high biocompatibility. Our results confirm that Au@LTSL-Ru can effectively inhibit tumor growth and aid the development of Ru for use in the thermal response in anti-tumor activity research.

14.
Sensors (Basel) ; 21(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34372299

RESUMO

The accuracy of target distance obtained by a frequency modulated continuous wave (FMCW) laser ranging system is often affected by factors such as white Gaussian noise (WGN), spectrum leakage, and the picket fence effect. There are some traditional spectrum correction algorithms to solve the problem above, but the results are unsatisfactory. In this article, a decomposition filtering-based dual-window correction (DFBDWC) algorithm is proposed to alleviate the problem caused by these factors. This algorithm reduces the influence of these factors by utilizing a decomposition filtering, dual-window in time domain and two phase values of spectral peak in the frequency domain, respectively. With the comparison of DFBDWC and these traditional algorithms in simulation and experiment on a built platform, the results show a superior performance of DFBDWC based on this platform. The maximum absolute error of target distance calculated by this algorithm is reduced from 0.7937 m of discrete Fourier transform (DFT) algorithm to 0.0407 m, which is the best among all mentioned spectrum correction algorithms. A high performance FMCW laser ranging system can be realized with the proposed algorithm, which has attractive potential in a wide scope of applications.

15.
Int J Biol Sci ; 17(9): 2135-2146, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34239344

RESUMO

The phenotypic transformation of hepatic myofibroblasts (MFs) is involved in the whole process of the progression and regression of liver fibrosis. Notch signaling has been demonstrated to modulate the fibrosis. In this study, we found that Notch signaling in MFs was overactivated and suppressed with the progression and regression of hepatic fibrosis respectively, by detecting Notch signaling readouts in MFs. Moreover, we inactivated Notch signaling specifically in MFs with Sm22αCreER-RBPjflox/flox mice (RBPjMF-KO), and identified that MFs-specific down-regulation of Notch signaling significantly alleviated CCl4-induced liver fibrosis during the progression and regression. During the progression of liver fibrosis, MFs-specific blockade of Notch signaling inhibited the activation of HSCs to MFs and increases the expression of MMPs to reduce the deposition of ECM. During the regression of fibrosis, blocking Notch signaling in MFs increased the expression of HGF to promote proliferation in hepatocytes and up-regulated the expression of pro-apoptotic factors, Ngfr and Septin4, to induce apoptosis of MFs, thereby accelerating the reversal of fibrosis. Collectively, the MFs-specific disruption of Notch signaling attenuates liver fibrosis by modulating fibrosis progression and regression, which suggests a promising therapeutic strategy for liver fibrosis.

16.
Molecules ; 26(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299455

RESUMO

An unprecedented novel flavanone davidone F (1) with a seven-membered ring side chain, and a novel flavanonol davidone G (2), along with 11 known flavonoids, were isolated from the ethyl acetate fraction of Sophora davidii (Franch.) Skeels. Their planar structures were established by UV, IR, HRESIMS, 1D and 2D NMR data. The relative configurations of 1 and 2 were determined by calculation of NMR chemical shift values, the absolute configuration of 1 and 2 were assigned by comparing their experimental and calculated electronic circular dichroism (ECD) spectra. Moreover, compounds 1-13 were screened for the translocation activity of glucose transporter 4 (GLUT-4), and the fluorescence intensity was increased to the range of 1.56 and 2.79 folds. Compounds 1 and 2 showed moderate GLUT-4 translocation activity with 1.64 and 1.79 folds enhancement, respectively, at a concentration of 20 µg/mL.


Assuntos
Flavonoides/química , Flavonoides/isolamento & purificação , Sophora/metabolismo , China , Dicroísmo Circular/métodos , Flavanonas/química , Flavanonas/isolamento & purificação , Transportador de Glucose Tipo 4/efeitos dos fármacos , Transportador de Glucose Tipo 4/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular , Raízes de Plantas/química , Sophora/química
17.
J Craniofac Surg ; 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34260450

RESUMO

ABSTRACT: Scalp reconstruction for a critical neurosurgical patient, as lifesaving efforts continued, can be challenging and a free tissue transfer is often needed to achieve reliable soft tissue coverage. However, the patient's labile perioperative condition may compromise successful reconstruction and perioperative hypotension is one of the major known factors for the failure of free tissue transfer. In this report, the authors encountered such an instance, and present our strategy in overcoming this hurdle toward obtaining successful scalp reconstruction with second free tissue transfer after the first free flap loss. After optimizing the patient's medical condition, the second free tissue transfer was performed in 2 stages with recipient vessel dissection during the first stage and the flap harvest and microvascular anastomoses during the second stage. Our staged approach is warranted to ensure the patient can tolerate the stressor of general anesthesia and to precondition the patient for ultimate successful second free tissue transfer.

18.
Aesthet Surg J Open Forum ; 3(1): ojab004, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34212139

RESUMO

Nipple-areola complex (NAC) reconstruction is an important part of breast reconstruction. Although several techniques for NAC reconstruction have been described in the literature, the long-term outcomes after NAC reconstruction remain less satisfactory, especially following implant-based breast reconstruction. The authors reported their newly developed technique for NAC reconstruction in implant-based breast reconstruction. The authors describe their modified skate flap, by preserving more dermal tissues from the skate flap, for NAC reconstruction, following implant-based breast reconstruction. Additional derma-fat grafts, harvested from the full-thickness skin graft site, are also added to the reconstructed nipple to ensure long-term shape, size, and projection of the reconstructed nipple. A total of 30 patients underwent such a NAC reconstruction after successful implant-based breast reconstruction by the senior author. The minimum follow-up time was 1 year. No significant surgical complications have been observed in their series of 30 patients, and only a minor office procedure was performed subsequently in 6 patients (4 unilateral and 2 bilateral) to improve the shape of the reconstructed nipple. During a minimum of a 1-year follow-up period, outcomes with the authors' technique in 30 patients are satisfactory; good size, shape, and projection of the reconstructed nipple are maintained. The long-term outcome of NAC reconstruction after implant-based breast reconstruction can be optimized with their modified skate flap by using all available flap tissue and with the addition of derma-fat grafts. The authors' technique can be used safely for NAC reconstruction after implant-based breast reconstruction with good outcome and high patient satisfaction.

19.
Curr Protoc ; 1(7): e188, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34232574

RESUMO

Backbone-modified nucleic acids are usually more stable enzymatically than their natural counterparts, enabling their broad application as potential diagnostic or therapeutic agents. Moreover, the development of nucleic acids with unnatural backbones has expanded the pool of genetic information carriers and paved the way toward synthetic xenobiology. However, synthesizing these molecules remains very challenging due to the requirement for harsh reaction conditions and the low coupling efficiency during their traditional solid-phase synthesis. Although enzymatic synthesis provides an attractive alternative that also allows the replication and artificial evolution of these molecules, it is crucially dependent on the availability of polymerases capable of synthesizing these backbone-modified nucleotides. Previously, a series of thermostable polymerases that can efficiently synthesize or even amplify backbone-modified DNA or RNA have been evolved through a polymerase evolution method based on phage display. Herein we summarize protocols to use these evolved polymerase mutants to transcribe, reverse transcribe, and PCR amplify backbone-modified nucleic acids. We also outline the polymerase chain transcription method, developed later for the rapid production of RNA or backbone-modified RNA with one of these evolved polymerases, SFM4-3. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Transcription/synthesis of modified DNA/RNA from DNA templates with evolved polymerases SFM4-3 or SFM4-6 Basic Protocol 2: Reverse transcription of modified DNA/RNA with evolved polymerase SFM4-9 Basic Protocol 3: PCR amplification of modified DNA with evolved polymerase SFM4-3 Basic Protocol 4: Polymerase chain transcription for the production of RNA/modified RNA oligonucleotides with evolved polymerase SFM4-3.


Assuntos
Ácidos Nucleicos , Transcrição Reversa , DNA/genética , DNA Polimerase Dirigida por DNA/genética , Laboratórios , Ácidos Nucleicos/genética
20.
Front Cell Infect Microbiol ; 11: 659505, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307190

RESUMO

The features of the vaginal microbiota (VM) community can reflect health status, and they could become new biomarkers for disease diagnosis. During pregnancy, domination of bacteria of the genus Lactobacillus in the VM community is regarded as a keystone because they stabilize the VM by producing antimicrobial compounds and competing adhesion. An altered VM composition provides a marker for adverse pregnancy outcomes. This nested case-control study aimed to characterize the VM in women with a tubal pregnancy (TP) presenting with pain and/or uterine bleeding in early pregnancy. Chinese women with a symptomatic early pregnancy of unknown location were the study cohort. 16S rDNA gene-sequencing of V3-V4 variable regions was done to assess the diversity, structures, taxonomic biomarkers, and classification of the VM community. The primary outcome was the location of the early pregnancy. The VM community in women with a TP showed higher diversity (PD-whole-tree, median: 8.26 vs. 7.08, P = 0.047; Shannon Diversity Index, median: 1.43 vs 0.99, P = 0.03) and showed different structures to those in women with an intrauterine pregnancy (IUP) (R = 0.23, P < 0.01). Bacteria of the genus Lactobacillus were significantly enriched in the IUP group, whereas bacteria of the genera Gardnerella and Prevotella were significantly enriched in the TP group. Lactobacillus abundance could be used to classify the pregnancy location (AUC = 0.81). Non-Lactobacillus-dominated microbiota (≤ 0.85% Lactobacillus) was significantly associated with a TP (adjusted odds ratio: 4.42, 95% confidence interval: 1.33 to 14.71, P = 0.02). In conclusion, among women with a symptomatic early pregnancy, a higher diversity and lower abundance of Lactobacillus in the VM is associated with a TP.


Assuntos
Microbiota , Gravidez Tubária , Estudos de Casos e Controles , China , Feminino , Humanos , Lactobacillus/genética , Gravidez , RNA Ribossômico 16S/genética , Vagina
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