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1.
Int Wound J ; 21(3): e14539, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38506317

RESUMEN

This study aimed to comprehensively evaluate the effects of evidence-based nursing (EBN) intervention on wound infection and postoperative complications in patients after appendectomy for acute appendicitis (AA), with the expectation of providing a theoretical basis for postoperative care in AA. Randomised controlled trials (RCTs) on the postoperative application of EBN in patients with AA were searched in PubMed, Web of Science, Cochrane Library, Embase, China Biomedical Literature Database, Wanfang and China National Knowledge Infrastructure from the inception of databases to October 2023. Two authors screened and evaluated the literature based on the inclusion and exclusion criteria, and data were extracted from the final included literature. Stata software (version 17.0) was employed for data analysis. In total, 29 RCTs involving 2848 patients with AA were included, with 1424 in the EBN group and 1424 in the conventional care group. The analyses revealed that patients with AA who experienced EBN were significantly less likely to develop postoperative wound infections (odds ratio [OR] = 0.23, 95% confidence intervals [CIs]: 0.14-0.38, p < 0.001) and postoperative complications (OR = 0.20, 95% CI: 0.15-0.26, p < 0.001) as opposed to conventional care. Available evidence suggests that EBN can effectively reduce the risk of wound infection and postoperative complications in patients undergoing appendectomy for AA, thereby improving patient prognosis. This finding is worth promoting in the clinical practice.


Asunto(s)
Apendicitis , Infección de la Herida Quirúrgica , Humanos , Infección de la Herida Quirúrgica/etiología , Apendicitis/cirugía , Enfermería Basada en la Evidencia , Apendicectomía/efectos adversos , China/epidemiología
2.
Plant Physiol ; 194(4): 2472-2490, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38217865

RESUMEN

LATERAL ORGAN BOUNDARIES DOMAIN/ASYMMETRIC LEAVES2-LIKEs (LBDs/ASLs) are plant-specific transcription factors that function downstream of auxin-regulated lateral root (LR) formation. Our previous research found that PpLBD16 positively regulates peach (Prunus persica) LR formation. However, the downstream regulatory network and target genes of PpLBD16 are still largely unknown. Here, we constructed a PpLBD16 homologous overexpression line and a PpLBD16 silenced line. We found that overexpressing PpLBD16 promoted peach root initiation, while silencing PpLBD16 inhibited peach root formation. Through RNA sequencing (RNA-seq) analysis of roots from PpLBD16 overexpression and silenced lines, we discovered that genes positively regulated by PpLBD16 were closely related to cell wall synthesis and degradation, ion/substance transport, and ion binding and homeostasis. To further detect the binding motifs and potential target genes of PpLBD16, we performed DNA-affinity purification sequencing (DAP-seq) analysis in vitro. PpLBD16 preferentially bound to CCNGAAANNNNGG (MEME-1), [C/T]TTCT[C/T][T/C] (MEME-2), and GCGGCGG (ABR1) motifs. By combined analysis of RNA-seq and DAP-seq data, we screened candidate target genes for PpLBD16. We demonstrated that PpLBD16 bound and activated the cell wall modification-related genes EXPANSIN-B2 (PpEXPB2) and SUBTILISIN-LIKE PROTEASE 1.7 (PpSBT1.7), the ion transport-related gene CYCLIC NUCLEOTIDE-GATED ION CHANNEL 1 (PpCNGC1) and the polyphenol oxidase (PPO)-encoding gene PpPPO, thereby controlling peach root organogenesis and promoting LR formation. Moreover, our results displayed that PpLBD16 and its target genes are involved in peach LR primordia development. Overall, this work reveals the downstream regulatory network and target genes of PpLBD16, providing insights into the molecular network of LBD16-mediated LR development.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Prunus persica , Factores de Transcripción/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Prunus persica/genética , Prunus persica/metabolismo , Regulación de la Expresión Génica de las Plantas , Transporte Iónico , Pared Celular/genética , Pared Celular/metabolismo , Raíces de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo
3.
Small ; 20(2): e2305670, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37658521

RESUMEN

N-type Mg3 Sb2 -based thermoelectric materials show great promise in power generation due to their mechanical robustness, low cost of Mg, and high figure of merit (ZT) over a wide range of temperatures. However, their poor thermal stability hinders their practical applications. Here, MgB2 is introduced to improve the thermal stability of n-type Mg3 Sb2 . Enabled by MgB2 decomposition, extra Mg can be released into the matrix for Mg compensation thermodynamically, and secondary phases of Mg─B compounds can kinetically prevent Mg diffusion along grain boundaries. These synergetic effects inhibit the formation of Mg vacancies at elevated temperatures, thereby enhancing the thermal stability of n-type Mg3 Sb2 . Consequently, the Mg3.05 (Sb0.75 Bi0.25 )1.99 Te0.01 (MgB2 )0.03 sample exhibits negligible variation in thermoelectric performance during the 120-hour continuous measurement at 673 K. Moreover, the ZT of n-type Mg3 Sb2 can be maintained by adding MgB2 , reaching a high average ZT of ≈1.1 within 300-723 K. An eight-pair Mg3 Sb2 -GeTe-based thermoelectric device is also fabricated, achieving an energy conversion efficiency of ≈5.7% at a temperature difference of 438 K with good thermal stability. This work paves a new way to enhance the long-term thermal stability of n-type Mg3 Sb2 -based alloys and other thermoelectrics for practical applications.

4.
ACS Appl Mater Interfaces ; 15(51): 59444-59453, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38091379

RESUMEN

The photocatalytic oxygen evolution of bismuth oxybromide (BiOBr) is greatly hindered by its low visible-light response and high electron-hole recombination. Nonmetal doping can effectively alleviate these issues, leading to improvement in photocatalytic performance. Herein, Bi2Te3 was introduced as both the Te doping source and the morphology-control template to improve the photocatalytic performance of BiOBr. Appropriate amounts of Te are critical to maintain the ultrathin plate-like structure of BiOBr, whereas excessive Te results in the formation of a flower-like architecture. Oxygen evolution activity disclosed that a plate-like structure is essential for realizing higher performance owing to sufficient light utilization and efficient charge separation. An optimal oxygen evolution rate of 368.0 µmol h-1 g-1 was achieved for the Te-doped sample, which is 2.3-fold as that of the undoped BiOBr (158.9 µmol h-1 g-1). Theoretical calculations demonstrated that Te doping can induce impurity levels above the valence band of BiOBr, which slightly narrowed the band gap and strengthened the light absorption in the range of 400-800 nm. More importantly, Te dopants could act as shallow traps for confining the excited electrons, thus prolonging the carrier lifetime. This work provides a novel strategy to prepare highly efficient photocatalysts by simultaneously realizing morphology manipulation and nonmetal doping.

5.
BMC Plant Biol ; 23(1): 513, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37880593

RESUMEN

Resistance genes (R genes) are a class of genes that are immune to a wide range of diseases and pests. In planta, NLR genes are essential components of the innate immune system. Currently, genes belonging to NLR family have been found in a number of plant species, but little is known in peach. Here, 286 NLR genes were identified on peach genome by using their homologous genes in Arabidopsis thaliana as queries. These 286 NLR genes contained at least one NBS domain and LRR domain. Phylogenetic and N-terminal domain analysis showed that these NLRs could be separated into four subfamilies (I-IV) and their promoters contained many cis-elements in response to defense and phytohormones. In addition, transcriptome analysis showed that 22 NLR genes were up-regulated after infected by Green Peach Aphid (GPA), and showed different expression patterns. This study clarified the NLR gene family and their potential functions in aphid resistance process. The candidate NLR genes might be useful in illustrating the mechanism of aphid resistance in peach.


Asunto(s)
Áfidos , Proteínas de Arabidopsis , Arabidopsis , Animales , Proteínas de Arabidopsis/genética , Áfidos/fisiología , Leucina/genética , Filogenia , Arabidopsis/genética , Nucleótidos/metabolismo
6.
Nanomaterials (Basel) ; 13(17)2023 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-37686986

RESUMEN

In this study, a Cu NPs-incorporated carbon-containing mesoporous SiO2 (Cu/C-SiO2) was successfully synthesized through a grinding-assisted self-infiltration method followed by an in situ reduction process. The obtained Cu/C-SiO2 was then employed as a Fenton-like catalyst to remove tetracycline (TC) from aqueous solutions. TEM, EDS, XRD, N2 adsorption-desorption, FTIR, and XPS methods were used to characterize the crystal structure, morphology, porosity, chemical composition, and surface chemical properties of the catalyst. The effects of initial TC concentration, catalyst dosage, H2O2 dosage, solution pH, HA addition, and water media on the TC degradation over Cu/C-SiO2 were investigated. Scavenging and electrochemical experiments were then carried out to analyze the TC degradation mechanism. The results show that the Cu/C-SiO2 can remove 99.9% of the concentrated TC solution (C0 = 500 mg·L-1), and it can be used in a wide pH range (R.E. = 94-99%, pH = 3.0-11.0). Moreover, hydroxyl radicals (•OH) were detected to be the dominant reactive species in this catalytic system. This study provides a simple and promising method for the synthesis of heteroatom-containing mesoporous catalysts for the decomposition of antibiotics in wastewater.

7.
Adv Mater ; 35(48): e2306831, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37775094

RESUMEN

Revealing the photocatalytic mechanism between various junctions and catalytic activities has become a hotspot in photocatalytic systems. Herein, an internal molecular heptazine/triazine (H/T) junction in crystalline carbon nitride (HTCN) is constructed and devoted to selective two-electron oxygen reduction reaction (2e- ORR) for efficient hydrogen peroxide (H2 O2 ) production. In-situ X-ray diffraction spectra under various temperatures authenticate the successful formation of molecular H/T junction in HTCN during the calcining process rather than physically mixing. The increased surface photovoltage and transient photovoltage signals, and the decreased exciton binding energy undoubtably elucidate that an obvious increasement of carrier density and diffusion capability of photogenerated electrons are realized over HTCN. Additionally, the analyses of in situ photoirradiated Kelvin probe force microscopy and femto-second transient absorption spectra reveal the successful construction of the strong internal built-in-electric field and the existence of the majority of long-lived shallow trapped electrons associated with molecular H/T junction over HTCN, respectively. Benefiting from these, the photocatalytic results exhibit an incredible improvement (96.5-fold) for H2 O2 production. This novel work provides a comprehensive understanding of the long-lived reactive charges in molecular H/T junctions for strengthening the driving-force for photocatalytic H2 O2 production, which opens potential applications for enhancing PCN-based photocatalytic redox reactions.

8.
ACS Appl Mater Interfaces ; 15(37): 44194-44204, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37677049

RESUMEN

Supramolecular organogel coatings that can disinfect the deposited microbial pathogens are emerging as an effective vehicle to prevent pathogen transmission. However, the development of anti-pathogen supramolecular adhesives with mechanical robustness and controlled oil inclusion is technically challenging. Here, we report supramolecular adhesives with mechanical integrity and robust interfacial adhesion over a wide range of biogenic antimicrobial oil. Bifunctional monomers are synthesized and assembled into linear polymers with semicrystalline stackings through hierarchical hydrogen bonds, where incorporated bioactive oil could regulate the semicrystalline stackings into nanosized crystalline domains through intermolecular hydrogen bonds. The abundant bonding motifs provided by the supramolecular cross-linked networks could accommodate oil molecules with high inclusion capability and provide more interfacial binding sites with high adhesion strength, and the nanosized crystalline domains could stabilize the organogel network and compensate for the interactions with oil molecules to enhance structural and mechanical stability. In addition, rapid healing, robust adhesion, and antimicrobial and antiviral properties of the resultant organogel coatings are demonstrated. This study paves the way for the development of high-performance antimicrobial supramolecular adhesives with controlled oil inclusion, showing potential applications in soft robotics, tissue engineering, and biomedical devices.


Asunto(s)
Antiinfecciosos , Antiinfecciosos/farmacología , Antivirales , Sitios de Unión , Excipientes , Enlace de Hidrógeno
9.
J Sport Rehabil ; 32(8): 863-872, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37558223

RESUMEN

CONTEXT: Decreased muscle strength and balance in patients with functional ankle instability (FAI) can be effectively improved by ankle strength training. Low-load blood flow restriction (LL-BFR) training increases muscle size and strength, but there is limited evidence from studies on muscle strength and balance in FAI patients. OBJECTIVE: To study the effects of LL-BFR training versus high-load training (HLT) on muscle strength and balance in FAI patients. DESIGN: Randomized controlled trial. PARTICIPANTS: Forty-six young adults with a history of FAI. INTERVENTIONS: Participants in the LL-BFR and HLT groups performed 4 sets (30 × 15 × 15 × 15) of ankle training at 20% to 40% of the one-repetition maximum and 70% to 85% one-repetition maximum, respectively, twice a week for 6 weeks. MAIN OUTCOME MEASURE(S): Plantar flexion, dorsiflexion, inversion, and eversion muscle strength, and the Y-balance test scores were assessed at baseline and after 3 and 6 weeks; the thickness of the tibialis anterior, triceps surae, and peroneus longus muscles were assessed at baseline and after 6 weeks. RESULTS: Inversion, eversion, dorsiflexion, and plantar flexion muscle strength; tibialis anterior, triceps surae, and peroneus longus thickness; and Y-balance test scores were significantly increased in the LL-BFR group after 3 and 6 weeks compared with baseline (P < .05), with no significant difference between the LL-BFR and HLT groups after 6 weeks (P > .05). However, at the end of 3 weeks, eversion muscle strength and Y-balance test scores were significantly higher in the LL-BFR group than in the HLT group (P < .05). CONCLUSIONS: Over 6 weeks, LL-BFR training was as effective as HLT in improving ankle muscle strength, muscle thickness, and balance in FAI patients, but LL-BFR training improved the ankle eversion muscle strength and dynamic balance more than HLT did in the early stages of the intervention. This finding will provide a new intervention strategy for the clinical rehabilitation of FAI patients.


Asunto(s)
Tobillo , Entrenamiento de Fuerza , Adulto Joven , Humanos , Terapia de Restricción del Flujo Sanguíneo , Articulación del Tobillo , Músculo Esquelético/fisiología , Fuerza Muscular/fisiología
10.
Polymers (Basel) ; 15(15)2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37571150

RESUMEN

The light weight, electrical conductivity, environmental friendliness, and high mechanical properties of graphene/PEKK composites make them popular in biomedical, electronic component and aerospace fields. However, the compaction density and carbonization of the specimen influence the microstructure and conductivity of the graphene/PEKK composite prepared by in situ polymerization, so electromagnetic-assisted molding was used to manufacture products to avoid carbonization and enhance the compaction density. The effects of different discharge voltages on the microstructure of the formed graphene/PEKK specimens were compared. Increasing the discharge voltage will lead to a closer distribution of flake graphene in the matrix to improve the compaction density, mechanical performance and conductivity. At the same time, the numerical analysis model was validated by comparison with the compaction density of the experimental results. Based on this research, the stress/strain distribution on the specimen was obtained with increasing discharge voltages.

11.
Int J Mol Sci ; 24(11)2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37298372

RESUMEN

Selecting suitable promoters to drive gene overexpression can provide significant insight into the development of engineered bacteria. In this study, we analyzed the transcriptome data of Burkholderia pyrrocinia JK-SH007 and identified 54 highly expressed genes. The promoter sequences were located using genome-wide data and scored using the prokaryotic promoter prediction software BPROM to further screen out 18 promoter sequences. We also developed a promoter trap system based on two reporter proteins adapted for promoter optimization in B. pyrrocinia JK-SH007: firefly luciferase encoded by the luciferase gene set (Luc) and trimethoprim (TP)-resistant dihydrofolate reductase (TPr). Ultimately, eight constitutive promoters were successfully inserted into the probe vector and transformed into B. pyrrocinia JK-SH007. The transformants were successfully grown on Tp antibiotic plates, and firefly luciferase expression was determined by measuring the relative light unit (RLU). Five of the promoters (P4, P9, P10, P14, and P19) showed 1.01-2.51-fold higher activity than the control promoter λ phage transcriptional promoter (PRPL). The promoter activity was further validated via qPCR analysis, indicating that promoters P14 and P19 showed stable high transcription levels at all time points. Then, GFP and RFP proteins were overexpressed in JK-SH007. In addition, promoters P14 and P19 were successfully used to drive gene expression in Burkholderia multivorans WS-FJ9 and Escherichia coli S17-1. The two constitutive promoters can be used not only in B. pyrrocinia JK-SH007 itself to gene overexpression but also to expand the scope of application.


Asunto(s)
Complejo Burkholderia cepacia , Luciferasas de Luciérnaga , Regiones Promotoras Genéticas , Genes Reporteros
12.
Small ; 19(44): e2303840, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37381087

RESUMEN

N-type Mg3 (Bi, Sb)2 -based thermoelectric (TE) alloys show great promise for solid-state power generation and refrigeration, owing to their excellent figure-of-merit (ZT) and using cheap Mg. However, their rigorous preparation conditions and poor thermal stability limit their large-scale applications. Here, this work develops an Mg compensating strategy to realize n-type Mg3 (Bi, Sb)2 by a facile melting-sintering approach. "2D roadmaps" of TE parameters versus sintering temperature and time are plotted to understand the Mg-vacancy-formation and Mg-diffusion mechanisms. Under this guidance, high weight mobility of 347 cm2  V-1  s-1 and power factor of 34 µW cm-1  K-2 can be obtained for Mg3.05 Bi1.99 Te0.01 , and a peak ZT≈1.55 at 723 K and average ZT≈1.25 within 323-723 K can be obtained for Mg3.05 (Sb0.75 Bi0.25 )1.99 Te0.01 . Moreover, this Mg compensating strategy can also improve the interfacial connecting and thermal stability of corresponding Mg3 (Bi, Sb)2 /Fe TE legs. As a consequence, this work fabricates an 8-pair Mg3 Sb2 -GeTe-based power-generation device reaching an energy conversion efficiency of ≈5.0% at a temperature difference of 439 K, and a one-pair Mg3 Sb2 -Bi2 Te3 -based cooling device reaching -10.7 °C at the cold side. This work paves a facile way to obtain Mg3 Sb2 -based TE devices at low cost and also provides a guide to optimize the off-stoichiometric defects in other TE materials.

13.
Plants (Basel) ; 12(7)2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-37050118

RESUMEN

Peach (Prunus persica (L.) Batsch) is a fruit tree of economic and nutritional importance, but it is very sensitive to drought stress, which affects its growth to a great extent. Lauric acid (LA) is a fatty acid produced in plants and associated with the response to abiotic stress, but the underlying mechanism remains unclear. In this study, physiological analysis showed that 50 ppm LA pretreatment under drought stress could alleviate the growth of peach seedlings. LA inhibits the degradation of photosynthetic pigments and the closing of pores under drought stress, increasing the photosynthetic rate. LA also reduces the content of O2-, H2O2, and MDA under drought stress; our results were confirmed by Evans Blue, nitroblue tetrazolium (NBT), and DAB(3,3-diaminobenzidine) staining experiments. It may be that, by directly removing reactive oxygen species (ROS) and improving enzyme activity, i.e., catalase (CAT) activity, peroxidase (POD) activity, superoxide dismutase (SOD) activity, and ascorbate peroxidase (APX) activity, the damage caused by reactive oxygen species to peach seedlings is reduced. Peach seedlings treated with LA showed a significant increase in osmoregulatory substances compared with those subjected to drought stress, thereby regulating osmoregulatory balance and reducing damage. RNA-Seq analysis identified 1876 DEGs (differentially expressed genes) in untreated and LA-pretreated plants under drought stress. In-depth analysis of these DEGs showed that, under drought stress, LA regulates the expression of genes related to plant-pathogen interaction, phenylpropanoid biosynthesis, the MAPK signaling pathway, cyanoamino acid metabolism, and sesquiterpenoid and triterpenoid biosynthesis. In addition, LA may activate the Ca2+ signaling pathway by increasing the expressions of CNGC, CAM/CML, and CPDK family genes, thereby improving the drought resistance of peaches. In summary, via physiological and transcriptome analyses, the mechanism of action of LA in drought resistance has been revealed. Our research results provide new insights into the molecular regulatory mechanism of the LA-mediated drought resistance of peach trees.

14.
BMC Plant Biol ; 23(1): 122, 2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36864374

RESUMEN

BACKGROUND: HD-Zips (Homeodomain-Leucine Zippers) are a class of plant-specific transcription factors that play multiple roles in plant growth and development. Although some functions of HD-Zip transcription factor have been reported in several plants, it has not been comprehensively studied in peach, especially during adventitious root formation of peach cuttings. RESULTS: In this study, 23 HD-Zip genes distributed on 6 chromosomes were identified from the peach (Prunus persica) genome, and named PpHDZ01-23 according to their positions on the chromosomes. These 23 PpHDZ transcription factors all contained a homeomorphism box domain and a leucine zipper domain, were divided into 4 subfamilies(I-IV) according to the evolutionary analysis, and their promoters contained many different cis-acting elements. Spatio-temporal expression pattern showed that these genes were expressed in many tissues with different levels, and they had distinct expression pattern during adventitious root formation and development. CONCLUSION: Our results showed the roles of PpHDZs on root formation, which is helpful to better understand the classification and function of peach HD-Zip genes.


Asunto(s)
Prunus persica , Prunus persica/genética , Biología Computacional , Evolución Biológica , Leucina Zippers , Factores de Transcripción/genética
15.
Front Plant Sci ; 13: 986688, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36518518

RESUMEN

Silicon is a beneficial element for plant growth, as well as for improving plant resistance to multiple biotic and abiotic stresses. Gummosis is a common harmful disease in peach and is induced by many factors. However, the effect of silicon on gummosis of peach has not been determined yet. In this study, we reported that application of silicon significantly reduced gummosis by regulating biosynthesis of ethylene and polyamines in peach. Ethylene promoted the development of gummosis by inducing the expression of genes encoding cell wall degrading enzymes. While application of different types of polyamines, including spermidine and spermine, dramatically inhibited the occurrence of gummosis. Moreover, polyamines inhibited the ethylene biosynthesis by down-regulating expression of ethylene biosynthetic gene PpACS1 (1-aminocyclopropane -1-carboxylic acid synthase), as well as the enzymatic activity of ACS. We further found that application of silicon significantly restricted the development of gummosis in peach. Exogenous silicon dramatically inhibited expression of PpACS1 and the enzymatic activity of its product to reduce ethylene biosynthesis. Simultaneously, the activity of S-adenosylmethionine decarboxylase, a key enzyme in ployamines biosynthesis, was increased by 9.85% under silicon treatment, resulting in elevated accumulation of polyamines. Thus, our data proved that application of silicon restricted gummosis development by activating ployamines biosynthesis and inhibiting ethylene synthesis in peach.

16.
Front Plant Sci ; 13: 1025569, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36340368

RESUMEN

Water shortage is a key factor that can restrict peach tree growth. Plants produce fatty acids and the fatty acid derivatives lauric acid (LA) and 12-hydroxylauric acid (LA-OH), which are involved in abiotic stress responses, but the underlying stress response mechanisms remain unclear. In this study, physiological examination revealed that in Prunus persica (L.) Batsch, pretreatment with 50 ppm LA-OH and LA reduced drought stress, efficiently maintained the leaf relative water content, and controlled the relative conductivity increase. Under drought stress, LA-OH and LA treatments prevented the degradation of photosynthetic pigments, increased the degree of leaf stomatal opening and enhanced the net photosynthetic rate. Compared with drought stress, LA-OH and LA treatment effectively increased the net photosynthetic rate by 204.55% and 115.91%, respectively, while increasing the Fv/Fm by 2.75% and 7.75%, respectively, but NPQ decreased by 7.67% and 37.54%, respectively. In addition, the level of reactive oxygen species increased under drought stress. The content of O2 - in LA-OH and LA treatment decreased by 12.91% and 11.24% compared to CK-D, respectively, and the content of H2O2 decreased by 13.73% and 19.94%, respectively. At the same time, the content of malondialdehyde (MDA) decreased by 55.56% and 58.48%, respectively. We believe that the main reason is that LA-OH and LA treatment have improved the activity of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). The application of exogenous LA increased the levels of soluble sugars, soluble proteins, proline and free amino acids under drought stress, and maintained the osmotic balance of cells. Compared with CK-D treatment, it increased by 24.11%, 16.89%, 29.3% and 15.04%, respectively. At the same time, the application of exogenous LA-OH also obtained similar results. In conclusion, exogenous LA-OH and LA can alleviate the damage to peach seedlings caused by drought stress by enhancing the photosynthetic and antioxidant capacities, increasing the activities of protective enzymes and regulating the contents of osmotic regulators, but the molecular mechanism is still in need of further exploration.

17.
BMC Public Health ; 22(1): 1072, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35641969

RESUMEN

BACKGROUND: Food security, malnutrition, and poverty are some of the challenges that most of the sub-Saharan African countries have been historically facing. With the coming of Covid-19 pandemic, the sustainability of the Village Savings and Loans Association which are formed to counter fight these challenges is questioned. AIM: This study aimed to assess factors associated with the Sustainability of VSLAs amidst Covid-19 and its impacts on households' income levels. METHODS: An online cross-sectional design was conducted from November to January 2021, targeting VSLAs members in Mzuzu. A snowball and respondent-driven sampling technique were used to recruit the needful participants using a referral approach. IBM SPSS version 23 was used to perform descriptive statistics, Chi-Square, and binary logistic regression with unstandardized Beta (ß), Odds Ratios (OR), and 95% Confidence Interval (CI) being taken into account with P-value set at 0.1, 0.05 and 0.01 significance levels. RESULTS: Our study finds that household income declined by 54% for those earnings belonged to ˂ MK5,000, as compared to 38% and 15% for medium (MK5,000 ≥ MK10,000) and higher (> MK10,000) income bands respectively. Our study shows that gender (ß = 0.437, p = 0.094), age-group (ß = 1.317, p = 0.000), education (ß = 2.181, p = 0.047), share contributions (ß = 1.035, p = 0.008), meetings (ß = 0.572, p = 0.021), occupation (ß = -0.453, p = 0.106), and frequency of meeting (ß = -0.507, p = 0.049) were positively and negatively statistically significant predictors. CONCLUSION: According to the findings of this study, households with lower income earners, which is one of the indicators of poverty, are more affected by the pandemic than their counterparts. We urge that the Malawi governments should maintain and, if they haven't already, implement programs that support low-income households, such as transfer payments, which have been shown to uplift people out of income poverty in many developing countries.


Asunto(s)
COVID-19 , COVID-19/epidemiología , Estudios Transversales , Humanos , Renta , Malaui/epidemiología , Pandemias
18.
Plant Sci ; 322: 111362, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35753620

RESUMEN

Silicon (Si) is abundant in nature, and it has been proved to be beneficial for the healthy growth and development of many plant species, improve plant stress resistance. Gummosis in peach is an invasive disease that causes widespread and serious damage. Mechanical damage and ethylene (ETH) can induce gummosis in peach shoots in the field. In this research, we found that Si as a chemical substance or signal to enhance plant resistance can reduce the synthesis of ETH, thereby inhibiting gummosis in peach. The results showed that Si can decrease the rate of gummosis, reduce the expression level of PpACS1 (1-aminocyclopropane -1-carboxylate synthase gene) and reduce the enzyme activity of polygalacturonase (PG). It was further discovered that Si can regulate the gene expression of PpERF21 and PpERF27. Yeast one-hybrid and dual-luciferase reporter assays showed that PpERF21 and PpERF27, through direct interaction with the promoter of PpPG1, inhibited the transcriptional activation of PpPG1. Overexpression of PpERF21 and PpERF27 effectively reduced fruit colloid production when bacterial cells harbouring the expression vector were used to instantaneously infect peach fruit. These results show that Si can inhibit the synthesis of ETH and mediate PpERF21 and PpERF27 expression to inhibit the expression of PpPG1, thereby inhibiting gummosis in peach.


Asunto(s)
Prunus persica , Etilenos/metabolismo , Frutas/genética , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poligalacturonasa/genética , Poligalacturonasa/metabolismo , Prunus persica/genética , Prunus persica/metabolismo , Silicio/metabolismo , Silicio/farmacología
19.
BMC Musculoskelet Disord ; 23(1): 583, 2022 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-35710352

RESUMEN

BACKGROUND: It remains unclear etiology of cartilaginous tissues in osteoarthritis (OA) lesions. In this study, we hypothesized the accumulation of hypoxia-inducible factor (HIF) and activated apoptosis relate to condylar cartilage degeneration in vivo. METHODS: Malocclusion stress was applied for 2 weeks, 4 weeks and 8 weeks to induce an OA-like lesion animal model in rats. Histological analysis was performed by H&E staining and Safranin O/fast green staining. The expression levels of protein in condylar cartilage were examined by immunostaining to evaluate cartilage degeneration. RESULTS: We found apparent histological phenotypes associated with degeneration in the occlusion disorder (OD) stress group. The OD group at 4 weeks and 8 weeks had obviously reduced expression of Aggrecan (Acan) and type II collagen (Col II) in cartilage. In contrast, the OD groups had higher levels of ADAM metallopeptidase with thrombospondin type 5 (ADAMTS5) and matrix metallopeptidase 13 (MMP13) in the condylar cartilage than the control group. Moreover, the OD group cartilage had prominent degenerative changes with reduced levels of hypoxia inducible factor 1 alpha (HIF1α) and increased levels of hypoxia inducible factor 2 alpha (HIF2α) and the apoptosis factor Caspase3 in condylar cartilage at 8 weeks. CONCLUSION: Thus, abnormal hypoxic conditions inducing Occlusion disorder stress results in cartilage degeneration. opposite expression patterns of HIF1α and HIF2α could be involved in the pathogenesis of condylar cartilage degeneration and chondrocyte apoptosis. HIF2α may provide a potential negative feedback mechanism for HIF1α during cartilage damage.


Asunto(s)
Enfermedades de los Cartílagos , Cartílago Articular , Osteoartritis , Animales , Apoptosis , Enfermedades de los Cartílagos/patología , Cartílago Articular/patología , Condrocitos/metabolismo , Humanos , Hipoxia/metabolismo , Hipoxia/patología , Metaloproteinasa 13 de la Matriz/metabolismo , Osteoartritis/patología , Ratas , Articulación Temporomandibular/metabolismo , Articulación Temporomandibular/patología
20.
Polymers (Basel) ; 14(6)2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35335600

RESUMEN

The cold compaction of poly (ether ketone ketone) (PEKK) powder was studied by experiments and simulations based on the modified Doraivelu model. Although this model can successfully predict the compaction behavior of metal powders, discussion of the prediction of polymer powders is lacking. Based on the mechanical theory of metal plasticity, the modified Doraivelu model was established by introducing the material parameters m and n. The modified model can predict the compaction density of PEKK powder during cold compaction. A sub-increment method for this constitutive model was then established and implemented into a finite-element model by using the user-defined material subroutine UMAT in ABAQUS/Standard. Consequently, the material parameters of the modified Doraivelu model were identified by an inverse method using the experimental data and simulation results. It was found that when m = 0, n = 4, and the initial relative density was 0.4485, the simulation results were the closest to the experimental ones.

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