Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 182
Filtrar
1.
J Biol Eng ; 18(1): 27, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622739

RESUMO

The demands for novel and efficient therapies have gradually increased with the rising concerns of osteoporosis (OP). The most popular method in promoting bone regeneration during osteoporotic conditions consists of loading bioactive materials with different drugs to treat osteoporotic bones by either promoting the process of osteogenesis, or by inhibiting the activity of osteoclasts. By analyzing single cell sequencing results, we found that divalent metal transporter 1 (DMT1) played a role in OP. Based on our previous results, we found that melatonin (MT) suppressed expression of DMT1 induced by high glucose during OP, so we determined the efficacy of MT for the treatment of OP. However, the clinical effects of MT on OP were unsatisfactory. To enhance its biological efficacy, we combined MT with porous gelatin chitosan (chitosan) and the conductive material, PLA-b-AP-b-PLA (PAP), then determined how MT incorporation in chitosan@PAP nanoparticles affected the ability to promote MC3T3-E1 osteogenesis and mineralization, both in vitro and in vivo. The results confirmed the effect of MT on DMT1. We then prepared and characterized composites prepared as nanofibers, and determined the efficacy of MT combined with chitosan-PAP modified hydrogels as a slow-release system in a femur model of osteoporosis mice, with associated properties suitable for bone tissue engineering. The results indicated that MT-loaded chitosan@PAP nanospheres showed favorable osteogenic functions, both in vivo and in vitro, providing a practical solution for bone regeneration for OP patients.

2.
Radiat Oncol ; 19(1): 46, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594678

RESUMO

OBJECTIVE: To evaluate effects of bone marrow sparing (BMS) radiotherapy on decreasing the incidence of acute hematologic toxicity (HT) for locoregionally advanced cervical cancer (LACC) patients treated by pelvic irradiation. MATERIALS AND METHODS: LACC patients were recruited prospectively from May 2021 to May 2022 at a single center and were evenly randomized into the BMS group and the control group. All patients received pelvic irradiation with concurrent cisplatin (40 mg/m2 weekly), followed by brachytherapy and BM V40 < 25% in the BMS group was additionally prescribed. Acute HT was assessed weekly. Binary logistic regression model and receiver operating characteristic (ROC) curve were used for predictive value analysis. The trial was registered with Chinese clinical trial registry (ChiCTR2200066485). RESULTS: A total of 242 patients were included in the analysis. Baseline demographic, disease and treatment characteristics were balanced between the two groups. In the intention-to-treat population, BMS was associated with a lower incidence of grade ≥ 2 and grade ≥ 3 acute HT, leukopenia and neutropenia s(72.70% v 90.90%, P < 0.001*; 16.50% vs. 65.30%, P < 0.001*; 66.10% vs. 85.10%, P = 0.001*; 13.20% vs. 54.50%, P < 0.001*; 37.20% vs. 66.10%, P < 0.001*; 10.70% vs. 43.80%, P < 0.001*). BMS also resulted in decreased dose delivered to the organs at risk (OARs) including rectum, bladder and left and right femoral head. Univariate and multivariate analyses showed that BM V40 was an independent risk factor for grade ≥ 3 acute HT (odds ratio [OR] = 2.734, 95% confidence interval [CI] = 1.959-3.815, P < 0.001*). Cutoff value was 25.036% and area under the curve (AUC) was 0.786. The nomogram was constructed, which was rigorously evaluated and internally cross-validated, showing good predictive performance. CONCLUSIONS: Receiving BMS pelvic irradiation could reduce the incidence of acute HT in LACC patients, and BM V40 < 25% may be a significant factor in reducing the risks of acute HT.


Assuntos
Leucopenia , Lesões por Radiação , Radioterapia de Intensidade Modulada , Neoplasias do Colo do Útero , Feminino , Humanos , Medula Óssea/efeitos da radiação , Neoplasias do Colo do Útero/radioterapia , Estudos Prospectivos , Radioterapia de Intensidade Modulada/métodos , Dosagem Radioterapêutica , Cisplatino , Leucopenia/etiologia , Quimiorradioterapia/efeitos adversos , Lesões por Radiação/etiologia
3.
Front Public Health ; 12: 1352043, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481852

RESUMO

Objective: Mercury (Hg) contamination in the environment around mercury mines is often accompanied by heavy metal contamination. Methods: Here, we determined concentrations of chromium (Cr), zinc (Zn), strontium (Sr), barium (Ba), and lead (Pb) in duck eggs from a Hg mining area in Southwest China to assess the contamination and health risk. Results: Duck eggs obtained from the mining area exhibit higher concentrations of Cr, Zn, Sr, Ba, and Pb compared to those from the background area, with egg yolks containing higher metal levels than egg whites. Specifically, the mean Cr, Zn, Sr, Ba, and Pb concentrations of duck eggs from the Hg mining area are 0.38, 63.06, 4.86, 10.08, and 0.05 µg/g, respectively, while those from the background area are only 0.21, 24.65, 1.43, 1.05, and 0.01 µg/g. Based on the single-factor contamination index and health risk assessment, heavy metal contamination in duck eggs poses an ecological risk and health risk. Conclusion: This study provides important insight into heavy metal contamination in duck eggs from Hg mining areas.


Assuntos
Mercúrio , Metais Pesados , Animais , Mercúrio/análise , Patos , Chumbo , Metais Pesados/análise , Zinco/análise , Mineração
4.
BMC Med Educ ; 24(1): 172, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388937

RESUMO

BACKGROUND: Recently, there has been a concerted effort within medical schools to depart from conventional lecture-based learning approaches to alternative teaching methods such as team-based learning (TBL) and problem-based learning (PBL), with the aim of enhancing both student engagement and instructional efficacy. Despite this shift, a comprehensive review that directly compares the impacts of PBL and TBL methods in medical education is lacking. This study seeks to address this gap by conducting a meta-analysis that compares the effects of TBL and PBL in the context of medical education. METHODS: Studies from Embase, PubMed, Web of Science, China National Knowledge Infrastructure, and Chinese Wanfang Database were searched, from inception to July 11, 2023. A meta-analysis was performed using Stata 14.0, and a total of 10 studies (including 752 participants) were included. The standardized mean difference (SMD) was used to estimate pooled effects. Heterogeneity was detected using the I2 statistic and further explored using meta-regression analysis. RESULTS: Compared with PBL, TBL significantly increased the number of theoretical tests (SMD = 0.37, 95% CI: 0.02-0.73). Additionally, TBL greatly improved teamwork skills compared with PBL. However, there were no significant differences between the TBL and PBL groups concerning practical skill scores, learning interest, or understanding skills. CONCLUSION: TBL in the theoretical aspects of medical education appears to be more effective than PBL in improving theoretical test scores and teamwork skills, providing evidence for the implementation of TBL in medical education.


Assuntos
Educação Médica , Aprendizagem Baseada em Problemas , Humanos , Aprendizagem Baseada em Problemas/métodos , Aprendizagem , Educação Médica/métodos , Currículo , Avaliação Educacional
5.
J Biol Eng ; 18(1): 11, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254196

RESUMO

Disc degeneration often leads to a highly prevalent symptom known as low back pain. Healthy nucleus pulposus tissue exhibited a hypoxic environment devoid of blood vessels, while degenerated nucleus pulposus experienced hypoxic deterioration and the formation of new blood vessels. In this study, the expression of important genes like HIF-2α was found to vary between normal and degenerated nucleus pulposus cells when compared to the hypoxic surroundings. The aim of this study was to examine how HIF-2α is controlled in nucleus pulposus cells under hypoxic conditions and its role in angiogenic mechanisms. To assess the impact of gradual inhibition of HIF-2α on disc degeneration, we utilized PHBV-based synthetic materials loaded with inhibitors of HIF-2α. Specifically, we employed LPS and PT2399 loaded PHBV-PEG20k (PP20) to intervene with human nucleus pulposus cells. Additionally, we treated APD rat models with PT2399 loaded PP20 to evaluate its effects. The expression levels of target markers in nucleus pulposus cells were detected using PCR, WB, and immunofluorescence. Additionally, the effect of drugs on disc degeneration was identified through HE staining. The findings indicated that HIF-2α, CAIX, PPP1R15A, VEGFA, and EGLN3 could potentially serve as new indicators of disc degeneration. Additionally, HIF-2α might contribute to the progression of disc degeneration through involvement in angiogenesis and the regulation of hypoxia. Furthermore, the utilization of PT2399 loaded PHBV-PEG20k (PP20) could potentially offer a fresh alternative for treating disc degeneration.

6.
J Hazard Mater ; 465: 133191, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38071775

RESUMO

Mercury (Hg) is a globally distributed toxic metal and could pose serious harm to birds, which may ultimately threaten human health through poultry consumption. However, the avian Hg metabolism remains unclear. Poultry, like chickens, are more accessible human dietary sources than wild birds and are ideal proxies to study Hg metabolism in birds. In this study, the avian Hg metabolism is carefully investigated with hens fed by Hg-spiked (both inorganic mercury IHg and methylmercury MeHg) foods. Our results demonstrate that feces and eggs are the main removal pathways of Hg from hens, rather than feathers. Eggs show particularly rapid responses towards Hg exposures, thus could be more sensitive to environmental Hg pollution than feathers, feces or internal organs (and tissues). Egg yolk (with THg peak of 55.92 ng/g on Day 6) and egg white (THg peak of 1195.03 ng/g on Day 4) react as an effective bioindicator for IHg and MeHg exposure, respectively. In 90-day-single-dose exposure, IHg is almost completely excreted, while approximately 11% of MeHg remains in internal organs. Our study provides new insight into the metabolism and lifetime of IHg and MeHg in birds, advancing the understanding of the dynamics for human exposure to Hg through poultry products.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Humanos , Animais , Feminino , Compostos de Metilmercúrio/toxicidade , Biomarcadores Ambientais , Galinhas/metabolismo , Mercúrio/análise , Monitoramento Ambiental , Ovos
7.
Med Gas Res ; 14(1): 12-18, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37721250

RESUMO

Postherpetic neuralgia (PHN) seriously affects the quality of life of the elderly population. This study aimed to evaluate the efficacy of ozonated autohemotherapy (O3-AHT) combined with pulsed radiofrequency (PRF) in the treatment of thoracic PHN in older adults. The medical records of patients with thoracic PHN aged 65 years and older from June 2018 until March 2021 in Shengli Oilfield Central Hospital were reviewed. They were assigned into two groups: PRF alone (PRF group, n = 107) and PRF combined with O3-AHT (PRF + O3-AHT group, n = 109). Visual Analogue Scale for pain was evaluated at pre-treatment, 1 day, 1, 3 and 6 months after treatment. Quality of life and sleep quality were assessed using Short-Form 36 Health Survey and Athens Insomnia Scale at pre-treatment and 6 months post-treatment, respectively. The median age of patients in the PRF and PRF + O3-AHT groups were 69 (67-73) years and 68 (67-72) years, respectively. The former included 62 females and the latter included 51 females. Compared with pre-treatment, the Visual Analogue Scale scores of two groups declined at post-treatment. Patients in the PRF + O3-AHT group showed obviously lower Visual Analogue Scale scores compared with those in the PRF group at 1, 3, and 6 months after treatment and they had earlier withdrawal time for drugs. However, dizziness, tachycardia, sleepiness, and nausea were presented after combination therapy. These symptoms resolved spontaneously after a period of rest. Additionally, O3-AHT combined with PRF was associated with a significant decrease in the Athens Insomnia Scale score and with a significant improvement in every dimension of the Short-Form 36 Health Survey. To conclude, O3-AHT combined with PRF is an effective way to relieve thoracic PHN in older patients.


Assuntos
Neuralgia Pós-Herpética , Tratamento por Radiofrequência Pulsada , Distúrbios do Início e da Manutenção do Sono , Feminino , Humanos , Idoso , Neuralgia Pós-Herpética/terapia , Estudos Retrospectivos , Tratamento por Radiofrequência Pulsada/métodos , Qualidade de Vida
8.
Front Pharmacol ; 14: 1246783, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37663244

RESUMO

Introduction: Postoperative comprehensive treatment has become increasingly important in recent years. This study was to repair tissue defects resulting from the removal of diseased tissue and to eliminate or inhibit the recurrence and metastasis of residual tumors under the condition of reducing the systemic side effects of chemotherapeutic drugs. To address these challenges, multifunctional scaffolds based local drug delivery systems will be a promising solution. Methods: An optimal drug-loaded scaffold material PHBV-mPEG5k (PP5) was prepared, which is biocompatible, hydrophilic and biodegradable. Furthermore, this material showed to promote bone healing, and could be conveniently prepared into porous scaffold by freeze-drying the solution. By means of introducing melatonin (MT) into the porous surfaces, the MT loaded PP5 scaffold with desirable sustained release ability was successfully prepared. The effectiveness of the MT loaded PP5 scaffold in promoting bone repair and anti-tumor properties was evaluated through both in vivo and in vitro experiments. Results and Discussion: The MT loaded PP5 scaffold is able to achieve the desired outcome of bone tissue repair and anti-bone tumor properties. Furthermore, our study demonstrates that the PP5 scaffold was able to enhance the anti-tumor effect of melatonin by improving cellular autophagy, which provided a therapeutic strategy for the comprehensive postoperative treatment of osteosarcoma.

9.
Int J Mol Sci ; 24(17)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37686018

RESUMO

Rheumatoid arthritis (RA) is a multifaceted, chronic, progressive autoimmune disease. This study aims to explore the potential benefits of an enhanced drug delivery system utilizing optimized Gelatin Methacryloyl (GelMA) vectors in RA management. We evaluated the levels of miR-1124-3p and AGO1 in RA tissues and cell lines using qPCR, WB, and immunofluorescence. The effects of osthole on inflammatory response and joint morphology were determined by qPCR, H&E staining, and micro-CT. The data showed that miR-1224-3p was downregulated in RA tissues and HUM-iCell-s010RA cells, while the overexpression of miR-1224-3p in HUM-iCell-s010RA cells reduced the expression of IL-6 and IL-1ß. Luciferase assay demonstrated that AGO1 was a direct target gene of miR-1224-3p. Additionally, osthole treatment increased miR-1224-3p levels and decreased AGO1 expression. The release data showed that osthole loaded on GelMA was released at a slower rate than free osthole. Further studies in a mouse model of CIA confirmed that osthole-loaded GelMA was more effective in attenuating osteopenia in RA as well as alleviating autoimmune arthritis. These findings suggest that osthole can regulate the miR-1224-3p/AGO1 axis in RASFs cells and has the potential to be developed as a clinical anti-RA drug. GelMA could provide a new approach to long-term RA treatment.


Assuntos
Artrite Reumatoide , Doenças Autoimunes , MicroRNAs , Animais , Camundongos , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética , Hidrogéis , MicroRNAs/genética
10.
Polymers (Basel) ; 15(18)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37765527

RESUMO

Ferric stearate (FeSt3) is very efficient in accelerating polyethylene (PE) degradation, but there is a lack of exploration of its role in accelerating the early stages of polyethylene photo-oxidative degradation. This study aimed to investigate the effect of FeSt3 on the photo-oxidative degradation of PE films, especially in the early stages of photo-oxidative degradation. The results show that FeSt3 not only promotes the oxidative degradation of PE but also contributes significantly to the early behavior of photo-oxidative degradation. Moreover, the results of the density functional theory (DFT) calculations proved that the C-H in the FeSt3 ligand was more easily dissociated compared with the PE matrix. The generated H radicals participate in the coupling reaction of the primary alkyl macro radicals leading to the molecular weight reduction, thus significantly increasing the initial rate of molecular weight reduction of PE. Meanwhile, the transfer reaction of the dissociation-generated C-centered radicals induced the PE matrix to produce more secondary alkyl macroradicals, which shortened the time to enter the oxidative degradation stage. This finding reveals the mechanism by which FeSt3 promotes the degradation of PE at the early stage of photo-oxidative degradation. It provides guiding significance for the in-depth study of the early degradation behavior in photo-oxidative degradation on polyolefin/FeSt3 films.

11.
Small ; 19(52): e2303933, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37574266

RESUMO

Exploiting novel strategies for simultaneously harvesting ubiquitous, renewable, and easily accessible solar energy based on the photothermal effect, and efficiently storing the acquired thermal energy plays a vital role in revolutionizing the current fossil fuel-dominating energy structure. Developing black phosphorene-based phase-change composites with optimized photothermal conversion efficiencyand high latent heat is the most promising way to achieve efficient solar energy harvesting and rapid thermal energy storage. However, exfoliating high-quality black phosphorene nanosheets  remains challenging, Furthermore, an efficient strategy that can construct the aligned black phosphorene frameworks to maximize thermal conductivity enhancement is still lacking. Herein, high-quality black phosphorene nanosheets are prepared by an optimized exfoliating strategy. Meanwhile, by regulating the temperature gradient during freeze-casting, the framework consisting of shipshape aligned black phosphorene at long-range is successfully fabricated, improving the thermal conductivity of the poly(ethylene glycol) matrix up to 1.81 W m-1  K-1 at 20 vol% black phosphorene loading. The framework also endows the composite with excellent phase-change material encapsulation capacity and  high latent heat of 103.91 J g-1 . It is envisioned that the work advances the paradigm of contrasting frameworks with nanosheets toward controllable structure thermal enhancement of the composites.

12.
Front Microbiol ; 14: 1231978, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37637109

RESUMO

Soil microorganisms play important roles in promoting soil ecosystem restoration, but much of the current research has been limited to changes in microbial community structure in general, and little is known regarding the soil physicochemical property and microbial community structure. In this study, four organic fertilizers were first prepared based on tea oil camellia shell (TOCS). Our findings indicate that the application of BOFvo increased both total pore volume and BET surface area of the rhizosphere soils, as well there was a remarkable enhancement in total organic matter (TOM), total nitrogen (TN), available nitrogen (AN), total phosphorus (TP), total potassium (TK), and available potassium (AK) contents of the rhizosphere soils. Meanwhile, in comparison to the CK and CF groups, the utilization of BOFvo led to a substantial increase in both average yield and fruiting rate per plant at maturity, as well resulted in a significant increase in TN and TP contents of tea oil camellia leaves. Furthermore, our findings suggest that the application of TOCS-based organic fertilizers significantly enhances the microbial diversity in the rhizosphere soils with Proteobacteria and Ascomycota being the dominant bacterial and fungal phyla, respectively, and Rhodanobacter and Fusarium being the dominant bacterial and fungal genus, respectively. Redundancy analysis (RDA) indicates that the physicochemical characteristics of TOCS-based organic fertilizers had a significant impact on the composition and distribution of microbial communities in the rhizosphere soils. This study will facilitate the promotion and application of TOCS-based organic fertilizers, thereby establishing a foundation for the reuse of tea oil camellia waste resources.

13.
Front Med (Lausanne) ; 10: 1194521, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37435537

RESUMO

Introduction: Approximately 40% of patients with acute low back pain (LBP) develop chronic low back pain, which significantly increases the risk of poor prognosis. To reduce the risk of acute LBP becoming chronic, effective preventive strategies are needed. Early identification of risk factors for the development of chronic LBP can help clinicians choose appropriate treatment options and improve patient outcomes. However, previous screening tools have not considered medical imaging findings. The aim of this study is to identify factors that can predict the risk of acute LBP becoming chronic based on clinical information, pain and disability assessment, and MRI imaging findings. This protocol describes the methodology and plan for investigating multidimensional risk factors for acute LBP becoming chronic, in order to better understand the development of acute LBP and prevent chronic LBP. Methods: This is a prospective multicenter study. We plan to recruit 1,000 adult patients with acute low back pain from four centers. In order to select four representative centers, we find the larger hospitals from different regions in Yunnan Province. The study will use a longitudinal cohort design. Patients will undergo baseline assessments upon admission and will be followed up for 5 years to collect the time of chronicity and associated risk factors. Upon admission, patients will be collected detailed demographic information, subjective and objective pain scores, disability scale, and lumbar spine MRI scanning. In addition, patient's medical history, lifestyle, psychological factors will be collected. Patients will be followed up at 3 months, 6 months, 1 year, 2 years and up for 5 years after admission to collect the time of chronicity and associated factors. Multivariate analysis will be used to explore the multidimensional risk factors affecting the chronicity of acute LBP patients (such as age, gender, BMI, degree of intervertebral disc degeneration, etc.), and survival analysis will be performed to explore the impact of each factor on the time of chronicity. Ethics and dissemination: The study has been approved by the institutional research ethics committee of each study center (main center number: 2022-L-305). Results will be disseminated through scientific conferences and peer-reviewed publications, as well as meetings with stakeholders.

14.
Chin Med J (Engl) ; 136(16): 1949-1958, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37461235

RESUMO

BACKGROUND: Previous research demonstrated that a homozygous mutation of g.136372044G>A (S12N) in caspase recruitment domain family member 9 ( CARD9 ) is critical for producing Aspergillus fumigatus -induced ( Af -induced) T helper 2 (T H 2)-mediated responses in allergic bronchopulmonary aspergillosis (ABPA). However, it remains unclear whether the CARD9S12N mutation, especially the heterozygous occurrence, predisposes the host to ABPA. METHODS: A total of 61 ABPA patients and 264 controls (including 156 healthy controls and 108 asthma patients) were recruited for sequencing the CARD9 locus to clarify whether patients with this heterozygous single-nucleotide polymorphisms are predisposed to the development of ABPA. A series of in vivo and in vitro experiments, such as quantitative real-time polymerase chain reaction, flow cytometry, and RNA isolation and quantification, were used to illuminate the involved mechanism of the disease. RESULTS: The presence of the p.S12N mutation was associated with a significant risk of ABPA in ABPA patients when compared with healthy controls and asthma patients, regardless of Aspergillus sensitivity. Relative to healthy controls without relevant allergies, the mutation of p.S12N was associated with a significant risk of ABPA (OR: 2.69 and 4.17 for GA and AA genotypes, P = 0.003 and 0.029, respectively). Compared with patients with asthma, ABPA patients had a significantly higher heterozygous mutation (GA genotype), indicating that p.S12N might be a significant ABPA-susceptibility locus ( aspergillus sensitized asthma: OR: 3.02, P = 0.009; aspergillus unsensitized asthma: OR: 2.94, P = 0.005). The mutant allele was preferentially expressed in ABPA patients with heterozygous CARD9S12N , which contributes to its functional alterations to facilitate Af -induced T H 2-mediated ABPA development. In terms of mechanism, Card9 wild-type ( Card9WT ) expression levels decreased significantly due to Af -induced decay of its messenger RNA compared to the heterozygous Card9S12N . In addition, ABPA patients with heterozygous CARD9S12N had increased Af -induced interleukin-5 production. CONCLUSION: Our study provides the genetic evidence showing that the heterozygous mutation of CARD9S12N , followed by allele expression imbalance of CARD9S12N , facilitates the development of ABPA.


Assuntos
Aspergilose Broncopulmonar Alérgica , Asma , Humanos , Aspergilose Broncopulmonar Alérgica/genética , Aspergilose Broncopulmonar Alérgica/complicações , Aspergillus fumigatus/genética , Asma/genética , Aspergillus , Mutação/genética , Proteínas Adaptadoras de Sinalização CARD/genética
15.
Polymers (Basel) ; 15(14)2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37514463

RESUMO

To optimize the bamboo heat treatment process, the corresponding evolution rules under various heat treatment conditions must be determined. When the heat treatment time and temperature remained constant, the effects of different heat treatment pressures on the equilibrium moisture content, dimensional stability, mechanical properties, and chemical composition of bamboo were systematically investigated. In this experiment, bamboo without heat treatment was used as the control group. The experimental findings demonstrate the following: (1) The equilibrium moisture content of heat-treated bamboo gradually decreases with increasing treatment pressure. When the heat treatment pressure was set at 0.1, 0.15, 0.2, and 0.25 MPa, the bamboo's equilibrium water content decreased to 12.1%, 11.7%, 9.9%, and 8.6%, respectively, while that of the control group was 13.8%. (2) The dimensional stability of bamboo was enhanced with increasing heat treatment pressure. At pressures of 0.1, 0.15, 0.2, and 0.25 MPa, the radial air-dry shrinkage rates of the heat-treated bamboo decreased to 3.4%, 3.4%, 2.6%, and 2.3%, respectively, while the tangential air-dry shrinkage rates reduced to 5.6%, 5.1%, 3.3%, and 3.0%. In comparison, the radial and tangential air-dry shrinkage rates of the control group were measured as 3.6% and 5.8%, respectively. Similarly, the radial and tangential full-dry shrinkage of bamboo exhibited a similar trend. (3) With the increase in heat treatment pressure, the bending strength and longitudinal compressive strength of bamboo exhibited an initial rise followed by a decline. When it was at heat treatment pressures of 0.1, 0.15, 0.2, and 0.25 MPa, the corresponding bending strengths of the heat-treated bamboo were measured as 41.2, 26.7, 22.4, and 20.4 MPa, respectively; while the longitudinal compressive strengths were recorded as 42.6, 38.1, 29.1, and 25.3 MPa. In comparison, the bending and longitudinal compressive strengths of the control group were measured as 39.8 and 38.5 MPa, respectively. It is evident that the optimal heat treatment pressure for bamboo is 0.1 MPa, resulting in a significant increase of 3.5% and 10.6% in bending strength and longitudinal compressive strength, respectively, compared to the control group. (4) Based on the FTIR and XRD patterns of bamboo samples, a range of physical and chemical transformations were observed during the heat treatment process, including cellulose adsorb water evaporation, hemicellulose and cellulose degradation, as well as acetyl group hydrolysis on the molecular chain of hemicellulose. These changes collectively impacted the physical and mechanical properties of bamboo.

16.
RSC Adv ; 13(24): 16693-16711, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37274402

RESUMO

Flexible human body electronic sensor is a multifunctional electronic device with flexibility, extensibility, and responsiveness. Piezoresistive flexible human body electronic sensor has attracted the extensive attention of researchers because of its simple preparation process, high detection sensitivity, wide detection range, and low power consumption. However, the wearability and affinity to the human body of traditional flexible human electronic sensors are poor, while polysiloxane materials can be mixed with other electronic materials and have good affinity toward the human body. Therefore, polysiloxane materials have become the first choice of flexible matrixes. In this study, the research progress and preparation methods of piezoresistive flexible human electronic sensors based on polysiloxane materials in recent years are summarized, the challenges faced in the development of piezoresistive flexible human electronic sensors are analyzed, and the future research directions are prospected.

17.
Mol Clin Oncol ; 19(1): 58, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37359715

RESUMO

Post-mastectomy radiotherapy (PMRT) is highly recommended for patients with breast cancer with one to three positive nodes; however, there remains some controversy regarding its use. The present retrospective study aimed to explore which patients may be able to avoid PMRT and its associated side effects. A total of 728 patients with T1-2N1 breast cancer who were treated with or without PMRT were included in the present study. The results suggested that PMRT significantly decreased the locoregional recurrence rate (LRR) [hazard ratio (HR)=5.602, 95% confidence interval (CI)=3.139-9.998, P<0.01; 3-year LRR: 4 vs. 17%] and improved overall survival (OS) (HR=0.651, 95% CI=0.437-0.971, P=0.03; 3-year OS: 91 vs. 87%) for patients with T1-2N1 breast cancer. By contrast, PMRT had no significant effect on the distant metastasis (DM) rate (HR=0.691, 95% CI=0.468-1.019, P=0.06; 3-year DM: 10 vs. 15%). Further stratified analysis revealed that PMRT did not reduce the LRR and DM, or improve OS in patients aged ≤35 years or in those with a positive human epidermal growth factor receptor-2 (HER-2) status. The analysis of 438 patients treated with PMRT revealed that patients aged ≤35 years or those with a positive HER-2 status were more likely to experience local recurrence even following PMRT. Thus, the benefits of using PMRT in patients with T1-2N1 breast cancer who are aged ≤35 years or in those with a positive HER-2 status need to be carefully considered. Further studies are required to confirm whether this patient group may be exempted from PMRT.

18.
Sci Bull (Beijing) ; 68(10): 1038-1050, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37173259

RESUMO

The association between polyploidy and reproduction transition, which is an intriguing issue in evolutionary genetics, can also be exploited as an approach for genetic improvement in agriculture. Recently, we generated novel amphitriploids (NA3n) by integrating the genomes of the gynogenetic Carassius gibelio and sexual C. auratus, and found gynogenesis was recovered in most NA3n females (NA3n♀I). Here, we discovered a unique reproduction mode, termed ameio-fusiongenesis, which combines the abilities of both ameiotic oogenesis and sperm-egg fusion, in a few NA3n females (NA3n♀II). These females inherited ameiotic oogenesis to produce unreduced eggs from gynogenetic C. gibelio and sperm-egg fusion from sexual C. auratus. Subsequently, we utilized this unique reproduction mode to generate a group of synthetic alloheptaploids by crossing NA3n♀II with Megalobrama amblycephala. They contained all chromosomes of maternal NA3n♀II and a chromosomal set of paternal M. amblycephala. Intergenomic chromosome translocations between NA3n♀II and M. amblycephala were also observed in a few somatic cells. Primary oocytes of the alloheptaploid underwent severe apoptosis owing to incomplete double-strand break repair at prophase I. Although spermatocytes displayed similar chromosome behavior at prophase I, they underwent apoptosis due to chromosome separation failure at metaphase I. Therefore, the alloheptaploid females and males were all sterile. Finally, we established a sustainable clone for the large-scale production of NA3n♀II and developed an efficient approach to synthesize diverse allopolyploids containing genomes of different cyprinid species. These findings not only broaden our understanding of reproduction transition but also offer a practical strategy for polyploidy breeding and heterosis fixing.


Assuntos
Carpas , Cyprinidae , Animais , Feminino , Masculino , Sêmen , Cyprinidae/genética , Poliploidia , Espermatozoides , Oogênese/genética
19.
Sci China Life Sci ; 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37202543

RESUMO

Gut barrier disruption is a key event in bridging gut microbiota dysbiosis and high-fat diet (HFD)-associated metabolic disorders. However, the underlying mechanism remains elusive. In the present study, by comparing HFD- and normal diet (ND)-treated mice, we found that the HFD instantly altered the composition of the gut microbiota and subsequently damaged the integrity of the gut barrier. Metagenomic sequencing revealed that the HFD upregulates gut microbial functions related to redox reactions, as confirmed by the increased reactive oxygen species (ROS) levels in fecal microbiota incubation in vitro and in the lumen, which were detected using in vivo fluorescence imaging. This microbial ROS-producing capability induced by HFD can be transferred through fecal microbiota transplantation (FMT) into germ-free (GF) mice, downregulating the gut barrier tight junctions. Similarly, mono-colonizing GF mice with an Enterococcus strain excelled in ROS production, damaged the gut barrier, induced mitochondrial malfunction and apoptosis of the intestinal epithelial cells, and exacerbated fatty liver, compared with other low-ROS-producing Enterococcus strains. Oral administration of recombinant high-stability-superoxide dismutase (SOD) significantly reduced intestinal ROS, protected the gut barrier, and improved fatty liver against the HFD. In conclusion, our study suggests that extracellular ROS derived from gut microbiota play a pivotal role in HFD-induced gut barrier disruption and is a potential therapeutic target for HFD-associated metabolic diseases.

20.
BMC Genomics ; 24(1): 183, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37024792

RESUMO

BACKGROUND: Red-tail catfish (Hemibagrus wyckioides) is an important commercially farmed catfish in southern China. Males of red-tail catfish grow faster than females, suggesting that all-male catfish will produce more significant economic benefits in aquaculture practice. However, little research has been reported on sex determination and gonadal development in red-tail catfish. RESULTS: In this study, we performed the first transcriptomic analysis of male and female gonads at four developmental stages at 10, 18, 30, and 48 days post hatching (dph) using RNA-seq technology. A total of 23,588 genes were screened in 24 sequenced samples, of which 28, 213, 636, and 1381 differentially expressed genes (DEGs) were detected at four developmental stages, respectively. Seven candidate genes of sex determination and differentiation were further identified. Real-time quantitative PCR (RT-qPCR) further confirmed that anti-Mullerian hormone (amh), growth differentiation factor 6a (gdf6a), testis-specific gene antigen 10 (tsga10), and cytochrome P450 family 17 subfamily A (cyp17a) were highly expressed mainly in the male, while cytochrome P450 family 19 subfamily A polypeptide 1b (cyp19a1b), forkhead box L2 (foxl2), and hydroxysteroid 17-beta dehydrogenase 1 (hsd17b1) were highly expressed in the female. The KEGG pathway enrichment data showed that these identified DEGs were mainly involved in steroid hormone biosynthesis and TGF-ß signaling pathways. CONCLUSIONS: Based on RNA-seq data of gonads at the early developmental stages, seven DEGs shared by the four developmental stages were identified, among which amh and gdf6a may be the male-biased expression genes, while foxl2, cyp19a1b and hsd17b1 may be the female-biased expression genes in red-tail catfish. Our study will provide crucial genetic information for the research on sex control in red-tail catfish, as well as for exploring the evolutionary processes of sex determination mechanisms in fish.


Assuntos
Peixes-Gato , Perciformes , Animais , Feminino , Masculino , Transcriptoma , Peixes-Gato/genética , Gônadas/metabolismo , Ovário/metabolismo , Perfilação da Expressão Gênica , Perciformes/genética , Diferenciação Sexual/genética , Regulação da Expressão Gênica no Desenvolvimento , Processos de Determinação Sexual/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...