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1.
Schizophr Res ; 270: 403-409, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38986387

RESUMEN

OBJECTIVE: Weight gain, blood lipids and/or glucose dysregulation can follow aripiprazole treatment onset. Whether aripiprazole dosage is associated with an increase in these metabolic parameters remains uncertain. The present study investigates aripiprazole dose associations with weight change, blood glucose, lipids, and blood pressure. METHODS: 422 patients taking aripiprazole for a minimum of three weeks to one year were selected from PsyMetab and PsyClin cohorts. Associations between aripiprazole dose and metabolic outcomes were examined using linear mixed-effect models. RESULTS: Aripiprazole dose was associated with weight change when considering its interaction with treatment duration (interaction term: -0.10, p < 0.001). This interaction resulted in greater weight gain for high versus low doses at the beginning of the treatment, this result being overturned at approximately five months, with greater weight increase for low versus high doses thereafter. LDL and HDL cholesterol levels were associated with aripiprazole dose over five months independently of treatment duration, with an average of 0.06 and 0.02 mmol/l increase for each 5 mg increment, respectively (p = 0.033 and p = 0.016, respectively). Furthermore, mean dose increases were associated with greater odds (+30 % per 5 mg increase) of clinically relevant weight gain (i.e., ≥7 %) over one year (p = 0.025). CONCLUSION: Aripiprazole dose was associated with one-year weight changes when considering its interaction with treatment duration. Increasing its dose could lead to metabolic worsening over the first five months of treatment, during which minimum effective doses should be particularly preferred.

2.
Front Endocrinol (Lausanne) ; 15: 1393865, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38978629

RESUMEN

Background: A common complication of thalassemia is secondary osteoporosis. This study aimed to assess the prevalence and factors associated with low BMD in thalassemic patients. Method: This is a cross-sectional study. Eligible patients were males aged within 18-49 years or premenopausal women diagnosed with thalassemia in Chiang Mai University Hospital between July 2021 and July 2022. The diagnosis of low BMD by dual-energy x-ray absorptiometry (DXA) was defined as a Z-score of -2.0 SD or lower in either the lumbar spine or femoral neck. Clinical factors associated with low BMD were analyzed using a logistic regression model. Results: Prevalence of low BMD was 62.4% from 210 patients with a mean age of 29.7 ± 7.6 years. The predominant clinical characteristics of low BMD thalassemia patients were being female, transfusion-dependent (TDT) and a history of splenectomy. From multivariable analysis, the independent variables associated with low BMD were transfusion dependency (odds ratio, OR 2.36; 95%CI 1.28 to 4.38; p=0.006) and body mass index (BMI) (OR 0.71; 95%CI 0.61 to 0.82; p<0.001). Among patients with low BMD, we observed a correlation between a Z-score with low IGF-1 levels (ß=-0.42; 95% CI -0.83 to -0.01; p=0.040), serum phosphate levels (ß=0.40; 95% CI 0.07 to 0.73; p=0.016) and hypogonadism (ß=-0.48, 95% CI -0.91 to -0.04, p=0.031). Conclusion: This study found a prevalence of low BMD in 62.4% of subjects. Factors associated with low BMD were TDT and BMI. Within the low BMD subgroup, hypogonadism, serum phosphate and low serum IGF-1 levels were associated with a lower Z-score.


Asunto(s)
Densidad Ósea , Talasemia , Humanos , Masculino , Femenino , Adulto , Estudios Transversales , Talasemia/epidemiología , Talasemia/complicaciones , Talasemia/sangre , Prevalencia , Factores de Riesgo , Adulto Joven , Adolescente , Persona de Mediana Edad , Osteoporosis/epidemiología , Osteoporosis/etiología , Absorciometría de Fotón
3.
Adv Contin Discret Model ; 2024(1): 22, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39027117

RESUMEN

We propose a unified stochastic SIR model driven by Lévy noise. The model is structural enough to allow for time-dependency, nonlinearity, discontinuity, demography, and environmental disturbances. We present concise results on the existence and uniqueness of positive global solutions and investigate the extinction and persistence of the novel model. Examples and simulations are provided to illustrate the main results.

4.
Demography ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39028635

RESUMEN

Population aging is an important and increasingly relevant area of study for demographers. A growing body of research seeks to determine how long-term changes in births, mortality, and migration-the three drivers of any demographic process-have shaped the present aging situation. Using variable-r decomposition and cohort data, this research note presents a formula for the change in the old-age dependency ratio to determine the extent to which relative changes in births, as well as in mortality and migration rates, contribute to aging. This perspective provides a careful and in-depth picture of aging and contributes to the debate concerning whether changes in births or mortality have had the strongest effect on population aging. When applied to Australia, the United States, and several European populations, the decomposition of the old-age dependency ratio shows that aging occurred in all populations and that changes in both births and mortality contributed to this aging. Analysis of these populations demonstrates that although they differed regarding which of these factors contributed more, changes in births prevailed as the more significant factor. In nearly all populations, migration decreased the rate of population aging.

5.
Gastric Cancer ; 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39033209

RESUMEN

BACKGROUND: Integrating molecular-targeted agents into combination chemotherapy is transformative for enhancing treatment outcomes in cancer. However, realizing the full potential of this approach requires a clear comprehension of the genetic dependencies underlying drug synergy. While the interactions between conventional chemotherapeutics are well-explored, the interplay of molecular-targeted agents with conventional chemotherapeutics remains a frontier in cancer treatment. Hence, we leveraged a powerful functional genomics approach to decode genomic dependencies that drive synergy in molecular-targeted agent/chemotherapeutic combinations in gastric adenocarcinoma, addressing a critical need in gastric cancer therapy. METHODS: We screened pharmacological interactions between fifteen molecular-targeted agent/conventional chemotherapeutic pairs in gastric adenocarcinoma cells, and examined the genome-scale genetic dependencies of synergy integrating genome-wide CRISPR screening with the shRNA-based signature assay. We validated the synergy in cell death using fluorescence-based and lysis-dependent inference of cell death kinetics assay, and validated the genetic dependencies by single-gene knockout experiments. RESULTS: Our combination screen identified SN-38/erlotinib as the drug pair with the strongest synergism. Functional genomics assays unveiled a genetic dependency signature of SN-38/erlotinib identical to SN-38. Remarkably, the enhanced cell death with improved kinetics induced by SN-38/erlotinib was attributed to erlotinib's off-target effect, inhibiting ABCG2, rather than its on-target effect on EGFR. CONCLUSION: In the era of precision medicine, where emphasis on primary drug targets prevails, our research challenges this paradigm by showcasing a robust synergy underpinned by an off-target dependency. Further dissection of the intricate genetic dependencies that underlie synergy can pave the way to developing more effective combination strategies in gastric cancer therapy.

6.
Artículo en Inglés | MEDLINE | ID: mdl-39033351

RESUMEN

OBJECTIVE: To assess the surgical outcomes and identify predictors of surgical success in patients with positional and non-positional obstructive sleep apnea following multilevel airway surgery. STUDY DESIGN: Retrospective cohort study. SETTING: Singe-tertiary medical center. METHODS: This study included 158 patients with obstructive sleep apnea who underwent multilevel airway surgery. Patients were divided into 2 groups according to position dependency: "positional patients" group (n = 100), and "nonpositional patients" group (n = 58). The characteristics and surgical outcomes of the 2 groups were compared. RESULTS: The nonpositional group included younger and more obese patients in comparison to the positional group. Moreover, the nonpositional group had more severe disease than the positional group. Both groups showed overall improvement after surgery, and the surgical success rate did not differ significantly between the 2 groups (nonpositional, 41.4% vs positional, 48.0%; P = .424). Notably, 69.0% of patients belonging to the non-positional group converted to positional group postoperatively. Logistic regression analysis revealed that larger tonsil size, female sex, and higher mean O2 saturation were associated with higher success rate in the positional group, whereas larger tonsil size was associated with surgical success in the nonpositional group. CONCLUSION: Both nonpositional and positional groups showed improvements following multilevel airway surgery, and surgery induced a transition from nonpositional to positional group. Given that the factors related to surgical success differed between the two groups, surgeons should consider position dependency and these distinct factors during decision-making.

7.
World Neurosurg ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39033808

RESUMEN

OBJECTIVE: Traumatic brain injury (TBI) significantly contributes to morbidity rates. While computed tomography (CT) scoring systems have been recognized as predictive factors for TBI outcomes, their association with shunt dependency in patients undergoing decompressive craniectomy (DC) has not been investigated. This study aimed to evaluate the predictive utility of CT scoring systems concerning shunt-dependent hydrocephalus in patients post-DC for TBI. METHODS: In this retrospective study, we enrolled 162 patients who underwent DC and survived more than 7 days following TBI. The pre-DC CT scans were evaluated using the Marshall, Rotterdam, and Helsinki CT scoring systems. The primary event of interest was shunt-dependent hydrocephalus during the follow-up period, with unfavorable outcomes denoted by a Glasgow Outcome Scale score ranging from 1 to 3. RESULTS: Analysis of the CT scans showed that the Rotterdam scores had a mean of 4.81 ± 0.91 for the group with shunt-dependent hydrocephalus and 4.41 ± 1.24 for the non-shunt-dependent hydrocephalus group (p = 0.033). However, multivariate logistic regression revealed no significant correlation between the Rotterdam CT score and shunt-dependent hydrocephalus, showing an odds ratio of 1.09 and a 95% confidence interval of 0.71 to 1.67 (p = 0.684). Notably, the Kaplan-Meier outcome curves highlighted a pronounced difference between groups based on shunt dependency (log-rank test: p = 0.012). CONCLUSIONS: The CT scoring systems proved insufficient for predicting shunt-dependent hydrocephalus following DC for TBI. However, our observations underscore a significant correlation between post-traumatic shunt dependency after DC and an increased incidence of unfavorable outcomes during long-term follow-up.

8.
Methods Mol Biol ; 2824: 203-219, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39039415

RESUMEN

Like all the RNA viruses, Rift Valley fever virus (RVFV) encodes only few viral proteins and relies heavily on the host cellular machinery for productive infection. This dependence creates a potential "Achille's heel" that may be exploited to develop new approaches to treat RVFV infection. The recent development of lentiviral sgRNAs pool has enabled the creation of genome-scale CRISPR-Cas9 knockout libraries that has been used to identify host factors required for virus replication. In this chapter, we describe the preparation and execution of a pooled CRISPR-Cas9 loss-of-function screen using virus-induced cell death phenotypic readout. Using this technique, we outline a strategy for the identification of host factors essential for important human emerging viruses such as RVFV.


Asunto(s)
Sistemas CRISPR-Cas , Virus de la Fiebre del Valle del Rift , Humanos , Virus de la Fiebre del Valle del Rift/genética , Replicación Viral/genética , Interacciones Huésped-Patógeno/genética , Técnicas de Inactivación de Genes , ARN Guía de Sistemas CRISPR-Cas/genética
10.
Ann Geriatr Med Res ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38952333

RESUMEN

Background: Functional dependency may serve as a marker for positive SARC-F screen among older adults at the Emergency Department (ED). We compared functional dependency between SARC-F- (<4) and SARC-F+ (≥4) groups at the ED. Methods: A secondary analysis of cohorts from two quasi-experimental studies among patients aged ≥65 years old presenting to the ED of a 1700-bed tertiary hospital. We compared both groups for baseline characteristics using univariate analyses, and performed multiple linear regression to examine the association between Modified Barthel Index (MBI) and Lawton's instrumental activities of daily living (IADL) against SARC-F, and binary logistic regression to examine the associations between individual ADL domains and SARC-F+. We compared the area under receiver operating characteristic curves (AUC) to detect SARC-F+ for MBI, IADL, frailty, age, cognition and comorbidity. Results: SARC-F+ patients were older (86.4±7.6 years), predominantly female (71.5%) and frail (73.9%), more dependent on walking aids (77.2%), and had lower premorbid MBI[90.0(71.0-98.0)] and IADL[4.0(2.0-5.0)] (both p<.001). MBI (ß -0.07, 95%CI:-0.086 to -0.055] and IADL (ß -0.533,95%CI:-0.684 to -0.381) were significantly associated with SARC-F. Dependency in finances [Odds Ratio(OR):14.7,95%CI:3.57-60.2, p<.001], feeding (OR:12.4,95%CI:1.45-106, p=0.022), and stair-climbing (OR:10.49,95%CI:4.96-22.2, p<.001) were the top 3 functional items associated with SARC-F. MBI (AUC:0.82,95%CI:0.77-0.84) and IADL (AUC:0.78,95%CI:0.72-0.84) showed superior discrimination for SARC-F+ compared to other measures (AUC:0.58-0.70). Conclusion: Functional dependency is strongly associated with positive SARC-F screen among older adults at the ED. This highlights the need for increased vigilance, especially in the presence of dependency in relevant domains such as managing finances, feeding, and stair-climbing.

11.
Sci Rep ; 14(1): 15510, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969827

RESUMEN

The optoelectronic and structural characteristics of the Zn1-xCrxSe (0 ≤ x ≤ 1) semiconductor are reported by employing density functional theory (DFT) within the mBJ potential. The findings revealed that the lattice constant decreases with increasing Cr concentration, although the bulk modulus exhibits the opposite trend. ZnSe is a direct bandgap material; however, a change from direct to indirect electronic bandgap has been seen with Cr presence. This transition is caused by structural alterations by Cr and defects forming, which results in novel optical features, including electronic transitions. The electronic bandgap decreases from 2.769 to 0.216 eV, allowing phonons to participate and improving optical absorption. A higher concentration of Cr boosts infrared absorption and these Cr-based ZnSe (ZnCrSe) semiconductors also cover a wider spectrum in the visible range from red to blue light. Important optical parameters such as reflectance, optical conductivity, optical bandgap, extinction coefficient, refractive index, magnetization factor, and energy loss function are discussed, providing a theoretical understanding of the diverse applications of ZnCrSe semiconductors in photonic and optoelectronic devices.

12.
Protein Expr Purif ; 222: 106539, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38960013

RESUMEN

PF11_0189 is a putative insulin degrading enzyme present in Plasmodium falciparum genome. The catalytic domain of PF11_0189 is about 27 kDa. Substrate specificity study shows PF11_0189 acts upon different types of proteins. The substrate specificity is found to be highest when insulin is used as a substrate. Metal dependency study shows highest dependency of PF11_0189 towards zinc metal for its proteolytic activity. Chelation of zinc metal with EDTA shows complete absence of PF11_0189 activity. Peptide inhibitors, P-70 and P-121 from combinatorial peptide library prepared against PF11_0189 show inhibition with an IC50 value of 4.8 µM and 7.5 µM respectively. A proven natural anti-malarial peptide cyclosporin A shows complete inhibition against PF11_0189 with an IC50 value of 0.75 µM suggesting PF11_0189 as a potential target for peptide inhibitors. The study implicates that PF11_0189 is a zinc metalloprotease involved in catalysis of insulin. The study gives a preliminary insight into the mechanism of complications arising from glucose abnormalities during severe malaria.


Asunto(s)
Insulisina , Plasmodium falciparum , Proteínas Protozoarias , Plasmodium falciparum/enzimología , Plasmodium falciparum/genética , Insulisina/genética , Insulisina/química , Insulisina/metabolismo , Proteínas Protozoarias/genética , Proteínas Protozoarias/química , Proteínas Protozoarias/metabolismo , Especificidad por Sustrato , Insulina/química , Insulina/metabolismo , Insulina/genética , Zinc/química , Zinc/metabolismo , Genoma de Protozoos , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/aislamiento & purificación , Expresión Génica , Clonación Molecular , Antimaláricos/química , Antimaláricos/farmacología , Ciclosporina/química , Ciclosporina/farmacología
13.
EClinicalMedicine ; 72: 102603, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39010979

RESUMEN

Background: The permanent pacemaker (PPM) implantation and pacemaker dependency rates after transcatheter aortic valve replacement (TAVR) are highly variable as some of the conduction disturbances are reversible. It remains poorly investigated how to optimise temporary pacing in these patients. This study aimed to explore the potential reduction in the PPM implantation rate using temporary-permanent pacemaker (TPPM) as a 1-month bridge. Methods: This is a prospective, multicentre, single-arm, observational study. Consecutive patients undergoing TAVR from March 1, 2022 to March 1, 2023 in 13 tertiary hospitals in China were screened. Patients who developed high-degree atrioventricular block, complete heart block, or first-degree atrioventricular block plus new onset left bundle branch block during the TAVR procedure or within 1 month after TAVR were included to receive TPPM. Patients with pre-existing PPM implantation or indications for PPM implantation before the TAVR procedure were excluded. Patients with TPPM were monitored to determine whether the conduction disturbances persisted or recovered. The primary endpoint was the rate of freedom from indications for PPM implantation 1 month after TAVR. This study is registered with ChiCTR, ChiCTR2200057931. Findings: Of 688 patients who have undergone TAVR, 71 developed conduction disturbance and met the inclusion criteria, 1 patient withdrew due to noncompliance, 70 patients received TPPM and completed follow-up. There were 41 (58.6%) men and 29 (41.4%) women in the study, with a mean age of 74.3 ± 7.3 years. At 1 month follow-up, 75.7% (53/70) of the patients with TPPM did not require PPM implantation. For 688 patients who have undergone TAVR, the rate of PPM implantation at 1 month was 2.47% (17/688, 95% CI 1.55%-3.92%), representing a significant reduction in self-comparison with the rate at 48 h after TPPM (2.47% vs. 8.28% [95% CI 6.45%-10.58%], P < 0.0001). Similar results were obtained in the subgroup analysis of patients with HAVB/CHB. Multivariate analysis revealed the baseline PR interval, difference between the membranous septum length and implantation depth, and timing of postprocedural conduction disturbance occurrence were independent predictors of freedom from indications for PPM implantation at 1 month after TAVR. Interpretation: Using TPPM as a 1-month bridge allows for a buffer period to distinguish whether conduction disturbances are reversible or persistent, resulting in a significant reduction in the PPM implantation rate after TAVR when compared with the current strategy. However, this is an observational study, the results need to be confirmed in a randomized trial. Funding: Beijing Science and Technology Plan 2022 from Beijing Municipal Science & Technology Commission.

14.
J Clin Nurs ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38932443

RESUMEN

BACKGROUND: The coexistence of frailty and type 2 diabetes mellitus in the older population heightens the risk of adverse events. However, research on functional and wellness factors associated with frailty in this population is limited. PURPOSE: To investigate the associations of physical performance, functional dependency, physical activity, nutritional status, sleep, self-perceived health and depression with frailty in community-dwelling older adults with coexisting frailty and type 2 diabetes mellitus. DESIGN: Cross-sectional. METHODS: The study included 123 community-dwelling older adults (73.7 ± 6.0 years) with pre-frailty/frailty and type 2 diabetes mellitus. Physical performance (Short Physical Performance Battery), functional dependency (Barthel Index and Lawton & Brody), physical activity and inactivity (GeneActiv wrist-worn accelerometer), malnutrition risk (Mini Nutritional Assessment), sleep (Pittsburgh Sleep Quality Index), self-perceived health (EuroQoL 5-Dimension 3-Level) and depression (Yesavage 15-item-Geriatric-Depression-Scale) were evaluated through personal interviews. Principal component analysis (PCA) was performed to categorize the variables into components, and logistic regressions were used to propose the best-fitted model for each component. RESULTS: The PCA identified four components: (i) physical performance, with gait speed and leg mean velocity as the main variables associated with frailty; (ii) balance, showing significant associations with monopodal balance; (iii) daily activities, with moderate to vigorous physical activity and the Lawton and Brody score as the main variables associated with frailty within this component; and (iv) wellness factors, with nutritional status, self-perceived health and depression score as the primary variables associated with frailty. CONCLUSIONS: This research underscores the significance of physical function and daily activities as protective factors against frailty in community-dwelling older adults with coexisting frailty and type 2 diabetes mellitus. The health dimension contributes both protective and risk factors, emphasizing the need for comprehensive assessments in managing frailty in this population. REPORTING METHOD: The study adhered to the STROBE checklist. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

15.
Artículo en Inglés | MEDLINE | ID: mdl-38842971

RESUMEN

BACKGROUND: There is limited information on the mode of arrhythmia initiation in idiopathic ventricular fibrillation (IVF). A non-pause-dependent mechanism has been suggested to be the rule. OBJECTIVES: The aim of this study was to assess the mode and characteristics of initiation of polymorphic ventricular tachycardia (PVT) in patients with short or long-coupled PVT/IVF included in THESIS (THerapy Efficacy in Short or long-coupled idiopathic ventricular fibrillation: an International Survey), a multicenter study involving 287 IVF patients treated with drugs or radiofrequency ablation. METHODS: We reviewed the initiation of 410 episodes of ≥1 PVT triplet in 180 patients (58.3% females; age 39.6 ± 13.6 years) with IVF. The incidence of pause-dependency arrhythmia initiation (prolongation by >20 ms of the preceding cycle length) was assessed. RESULTS: Most arrhythmias (n = 295; 72%) occurred during baseline supraventricular rhythm without ambient premature ventricular complexes (PVCs), whereas 106 (25.9%) occurred during baseline rhythm including PVCs. Nine (2.2%) arrhythmias occurred during atrial/ventricular pacing and were excluded from further analysis. Mode of PVT initiation was pause-dependent in 45 (15.6%) and 64 (60.4%) of instances in the first and second settings, respectively, for a total of 109 of 401 (27.2%). More than one type of pause-dependent and/or non-pause-dependent initiation (mean: 2.6) occurred in 94.4% of patients with ≥4 events. Coupling intervals of initiating PVCs were <350 ms, 350-500 ms, and >500 ms in 76.6%, 20.72%, and 2.7% of arrhythmia initiations, respectively. CONCLUSIONS: Pause-dependent initiation occurred in more than a quarter of arrhythmic episodes in IVF patients. PVCs having long (between 350 and 500 ms) and very long (>500 ms) coupling intervals were observed at the initiation of nearly a quarter of PVT episodes.

16.
Front Neurosci ; 18: 1394234, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38872940

RESUMEN

Computer aided diagnosis methods play an important role in Attention Deficit Hyperactivity Disorder (ADHD) identification. Dynamic functional connectivity (dFC) analysis has been widely used for ADHD diagnosis based on resting-state functional magnetic resonance imaging (rs-fMRI), which can help capture abnormalities of brain activity. However, most existing dFC-based methods only focus on dependencies between two adjacent timestamps, ignoring global dynamic evolution patterns. Furthermore, the majority of these methods fail to adaptively learn dFCs. In this paper, we propose an adaptive spatial-temporal neural network (ASTNet) comprising three modules for ADHD identification based on rs-fMRI time series. Specifically, we first partition rs-fMRI time series into multiple segments using non-overlapping sliding windows. Then, adaptive functional connectivity generation (AFCG) is used to model spatial relationships among regions-of-interest (ROIs) with adaptive dFCs as input. Finally, we employ a temporal dependency mining (TDM) module which combines local and global branches to capture global temporal dependencies from the spatially-dependent pattern sequences. Experimental results on the ADHD-200 dataset demonstrate the superiority of the proposed ASTNet over competing approaches in automated ADHD classification.

17.
J Biochem ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38861409

RESUMEN

In the chloroplast stroma, dynamic pH changes occur from acidic to alkaline in response to fluctuating light conditions. We investigated the pH dependency of the electron transfer reaction of ferredoxin-NADP+ reductase (FNR) with ferredoxin (Fd) isoproteins, Fd1 and Fd2, which are localized in mesophyll cells and bundle sheath cells, respectively, in the leaves of C4 plant maize. The pH-dependent profile of the electron transfer activity with FNR was quite different between Fd1 and Fd2, which was mainly explained by the opposite pH dependency of the Km value of these Fds for FNR. Replacement of the amino acid residue at position of 65 (D65N) and 78 (H78A) between the two Fds conferred different effect on their pH dependency of the Km value. Double mutations of the two residues between Fd1 and Fd2 (Fd1D65N/H78A and Fd2N65D/A78H) led to the mutual exchange of the pH dependency of the electron transfer activity. This exchange was mainly explained by the changes in the pH-dependent profile of the Km values. Therefore, the differences in Asp/Asn at position 65 and His/Ala at position 78 between Fd1 and Fd2 were shown to be the major determinants for their different pH dependency in the electron transfer reaction with FNR.

18.
Glob Chang Biol ; 30(6): e17365, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38864217

RESUMEN

Climate change will affect the way biodiversity influences the stability of plant communities. Although biodiversity, associated species asynchrony, and species stability could enhance community stability, the understanding of potential nonlinear shifts in the biodiversity-stability relationship across a wide range of aridity (measured as the aridity index, the precipitation/potential evapotranspiration ratio) gradients and the underlying mechanisms remain limited. Using an 8-year dataset from 687 sites in Mongolia, which included 5496 records of vegetation and productivity, we found that the temporal stability of plant communities decreased more rapidly in more arid areas than in less arid areas. The result suggests that future aridification across terrestrial ecosystems may adversely affect community stability. Additionally, we identified nonlinear shifts in the effects of species richness and species synchrony on temporal community stability along the aridity gradient. Species synchrony was a primary driver of community stability, which was consistently negatively affected by species richness while being positively affected by the synchrony between C3 and C4 species across the aridity gradient. These results highlight the crucial role of C4 species in stabilizing communities through differential responses to interannual climate variations between C3 and C4 species. Notably, species richness and the synchrony between C3 and C4 species independently regulated species synchrony, ultimately affecting community stability. We propose that maintaining plant communities with a high diversity of C3 and C4 species will be key to enhancing community stability across Mongolian grasslands. Moreover, species synchrony, species stability, species richness and the synchrony between C3 and C4 species across the aridity gradient consistently mediated the impacts of aridity on community stability. Hence, strategies aimed at promoting the maintenance of biological diversity and composition will help ecosystems adapt to climate change or mitigate its adverse effects on ecosystem stability.


Asunto(s)
Biodiversidad , Cambio Climático , Mongolia , Plantas , Clima Desértico , Ecosistema
19.
Front Neurosci ; 18: 1367266, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38846714

RESUMEN

Background: Vagus nerve stimulation (VNS) improves diseases such as refractory epilepsy and treatment-resistant depression, likely by rebalancing the autonomic nervous system (ANS). Intradermal auricular electro-acupuncture stimulation (iaES) produces similar effects. The aim of this study was to determine the effects of different iaES frequencies on the parasympathetic and sympathetic divisions in different states of ANS imbalance. Methods: We measured heart rate variability (HRV) and heart rate (HR) of non-modeled (normal) rats with the treatment of various frequencies to determine the optimal iaES frequency. The optimized iaES frequency was then applied to ANS imbalance model rats to elucidate its effects. Results: 30 Hz and 100 Hz iaES clearly affected HRV and HR in normal rats. 30 Hz iaES increased HRV, and decreased HR. 100 Hz iaES decreased HRV, and increased HR. In sympathetic excited state rats, 30 Hz iaES increased HRV. 100 Hz iaES increased HRV, and decreased HR. In parasympathetic excited state rats, 30 Hz and 100 Hz iaES decreased HRV. In sympathetic inhibited state rats, 30 Hz iaES decreased HRV, while 100 Hz iaES decreased HR. In parasympathetic inhibited rats, 30 Hz iaES decreased HR and 100 Hz iaES increased HRV. Conclusion: 30 Hz and 100 Hz iaES contribute to ANS rebalance by increasing vagal and sympathetic activity with different amplifications. The 30 Hz iaES exhibited positive effects in all the imbalanced states. 100 Hz iaES suppressed the sympathetic arm in sympathetic excitation and sympathetic/parasympathetic inhibition and suppressed the vagal arm and promoted the sympathetic arm in parasympathetic excitation and normal states.

20.
Front Aging Neurosci ; 16: 1366380, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38863785

RESUMEN

Objectives: To explore latent profiles of care dependency in older stroke patients with comorbidities and to analyze the factors influencing different latent profiles. Methods: A total of 312 older ischemic stroke patients with comorbidities were included in the analysis. Latent Profile Analysis (LPA) was used to classify the participants into potential subgroups with different types of care dependency. The influencing factors of the classification of care dependency subgroups were determined using multivariate Logistic regression analysis. Results: The care dependency score of older ischemic stroke patients with comorbidities was (51.35 ± 13.19), and the patients could be classified into 3 profiles, namely Universal dependency (24.0%), Moderate activity-social-learning dependency (28.0%), and Mild activity-social-learning dependency (48.0%); caregiver, BI at admission, and functional impairments were independent factors influencing care dependency (P < 0.05). Conclusion: There are three latent profiles of care dependency in older ischemic stroke patients with comorbidities. According to the characteristics of various populations, medical staff are able to implement specific interventions to lower the level of dependency and further improve the quality of life of patients.

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