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1.
Cell ; 177(6): 1632-1648.e20, 2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-31150626

RESUMO

The scaling of organelles with cell size is thought to be exclusive to eukaryotes. Here, we demonstrate that similar scaling relationships hold for the bacterial nucleoid. Despite the absence of a nuclear membrane, nucleoid size strongly correlates with cell size, independent of changes in DNA amount and across various nutrient conditions. This correlation is observed in diverse bacteria, revealing a near-constant ratio between nucleoid and cell size for a given species. As in eukaryotes, the nucleocytoplasmic ratio in bacteria varies greatly among species. This spectrum of nucleocytoplasmic ratios is independent of genome size, and instead it appears linked to the average population cell size. Bacteria with different nucleocytoplasmic ratios have a cytoplasm with different biophysical properties, impacting ribosome mobility and localization. Together, our findings identify new organizational principles and biophysical features of bacterial cells, implicating the nucleocytoplasmic ratio and cell size as determinants of the intracellular organization of translation.


Assuntos
Estruturas Celulares/metabolismo , Estruturas Celulares/fisiologia , Biossíntese de Proteínas/fisiologia , Bactérias/genética , Proteínas de Bactérias/metabolismo , Tamanho Celular , Citoplasma/fisiologia , DNA Bacteriano/metabolismo , Proteínas de Ligação a DNA/metabolismo , Organelas/metabolismo , Células Procarióticas/metabolismo , Células Procarióticas/fisiologia , Ribossomos/metabolismo
2.
Nature ; 599(7884): 273-277, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34707283

RESUMO

Growth regulation tailors development in plants to their environment. A prominent example of this is the response to gravity, in which shoots bend up and roots bend down1. This paradox is based on opposite effects of the phytohormone auxin, which promotes cell expansion in shoots while inhibiting it in roots via a yet unknown cellular mechanism2. Here, by combining microfluidics, live imaging, genetic engineering and phosphoproteomics in Arabidopsis thaliana, we advance understanding of how auxin inhibits root growth. We show that auxin activates two distinct, antagonistically acting signalling pathways that converge on rapid regulation of apoplastic pH, a causative determinant of growth. Cell surface-based TRANSMEMBRANE KINASE1 (TMK1) interacts with and mediates phosphorylation and activation of plasma membrane H+-ATPases for apoplast acidification, while intracellular canonical auxin signalling promotes net cellular H+ influx, causing apoplast alkalinization. Simultaneous activation of these two counteracting mechanisms poises roots for rapid, fine-tuned growth modulation in navigating complex soil environments.


Assuntos
Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Prótons , Transdução de Sinais , Álcalis , Arabidopsis/enzimologia , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/metabolismo , Ativação Enzimática , Proteínas F-Box/metabolismo , Concentração de Íons de Hidrogênio , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo
3.
Nature ; 599(7884): 278-282, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34707287

RESUMO

The phytohormone auxin controls many processes in plants, at least in part through its regulation of cell expansion1. The acid growth hypothesis has been proposed to explain auxin-stimulated cell expansion for five decades, but the mechanism that underlies auxin-induced cell-wall acidification is poorly characterized. Auxin induces the phosphorylation and activation of the plasma membrane H+-ATPase that pumps protons into the apoplast2, yet how auxin activates its phosphorylation remains unclear. Here we show that the transmembrane kinase (TMK) auxin-signalling proteins interact with plasma membrane H+-ATPases, inducing their phosphorylation, and thereby promoting cell-wall acidification and hypocotyl cell elongation in Arabidopsis. Auxin induced interactions between TMKs and H+-ATPases in the plasma membrane within seconds, as well as TMK-dependent phosphorylation of the penultimate threonine residue on the H+-ATPases. Our genetic, biochemical and molecular evidence demonstrates that TMKs directly phosphorylate plasma membrane H+-ATPase and are required for auxin-induced H+-ATPase activation, apoplastic acidification and cell expansion. Thus, our findings reveal a crucial connection between auxin and plasma membrane H+-ATPase activation in regulating apoplastic pH changes and cell expansion through TMK-based cell surface auxin signalling.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Membrana Celular/metabolismo , Parede Celular/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Ácidos , Arabidopsis/citologia , Arabidopsis/enzimologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Membrana Celular/enzimologia , Ativação Enzimática , Concentração de Íons de Hidrogênio , Hipocótilo/enzimologia , Hipocótilo/crescimento & desenvolvimento , Hipocótilo/metabolismo , Proteínas de Membrana/genética , Fosforilação , Reguladores de Crescimento de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , ATPases Translocadoras de Prótons/química , ATPases Translocadoras de Prótons/metabolismo , Prótons , Treonina/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(39): e2304513120, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37725643

RESUMO

Nitrate supply is fundamental to support shoot growth and crop performance, but the associated increase in stem height exacerbates the risks of lodging and yield losses. Despite their significance for agriculture, the mechanisms involved in the promotion of stem growth by nitrate remain poorly understood. Here, we show that the elongation of the hypocotyl of Arabidopsis thaliana, used as a model, responds rapidly and persistently to upshifts in nitrate concentration, rather than to the nitrate level itself. The response occurred even in shoots dissected from their roots and required NITRATE TRANSPORTER 1.1 (NRT1.1) in the phosphorylated state (but not NRT1.1 nitrate transport capacity) and NIN-LIKE PROTEIN 7 (NLP7). Nitrate increased PHYTOCHROME INTERACTING FACTOR 4 (PIF4) nuclear abundance by posttranscriptional mechanisms that depended on NRT1.1 and phytochrome B. In response to nitrate, PIF4 enhanced the expression of numerous SMALL AUXIN-UP RNA (SAUR) genes in the hypocotyl. The growth response to nitrate required PIF4, positive and negative regulators of its activity, including AUXIN RESPONSE FACTORs, and SAURs. PIF4 integrates cues from the soil (nitrate) and aerial (shade) environments adjusting plant stature to facilitate access to light.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fitocromo , Nitratos/farmacologia , Fitocromo B , Arabidopsis/genética , Ácidos Indolacéticos , Transportadores de Nitrato , RNA , Proteínas de Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética
5.
PLoS Genet ; 18(9): e1010375, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36121899

RESUMO

In plants, regulated cell expansion determines organ size and shape. Several members of the family of redundantly acting Small Auxin Up RNA (SAUR) proteins can stimulate plasma membrane (PM) H+-ATPase proton pumping activity by inhibiting PM-associated PP2C.D phosphatases, thereby increasing the PM electrochemical potential, acidifying the apoplast, and stimulating cell expansion. Similarly, Arabidopsis thaliana SAUR63 was able to increase growth of various organs, antagonize PP2C.D5 phosphatase, and increase H+-ATPase activity. Using a gain-of-function approach to bypass genetic redundancy, we dissected structural requirements for SAUR63 growth-promoting activity. The divergent N-terminal domain of SAUR63 has a predicted basic amphipathic α-helix and was able to drive partial PM association. Deletion of the N-terminal domain decreased PM association of a SAUR63 fusion protein, as well as decreasing protein level and eliminating growth-promoting activity. Conversely, forced PM association restored ability to promote H+-ATPase activity and cell expansion, indicating that SAUR63 is active when PM-associated. Lipid binding assays and perturbations of PM lipid composition indicate that the N-terminal domain can interact with PM anionic lipids. Mutations in the conserved SAUR domain also reduced PM association in root cells. Thus, both the N-terminal domain and the SAUR domain may cooperatively mediate the SAUR63 PM association required to promote growth.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Membrana Celular/genética , Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Lipídeos , Monoéster Fosfórico Hidrolases/genética , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo , Prótons , RNA/metabolismo
6.
Lancet ; 402(10415): 1848-1856, 2023 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-37890499

RESUMO

BACKGROUND: Numerous randomised clinical trials and real-world studies have supported the safety of paclitaxel-coated devices for the treatment of femoropopliteal occlusive disease. However, a 2018 summary-level meta-analysis suggested an increased mortality risk for paclitaxel-coated devices compared with uncoated control devices. This study presents an updated analysis of deaths using the most complete and current data available from pivotal trials of paclitaxel-coated versus control devices. METHODS: Ten trials comparing paclitaxel-coated versus control devices were included in a patient-level pooled analysis. Cox regression models were used to evaluate the effect of paclitaxel exposure on risk of death in both intention-to-treat (ITT; primary analysis) and three as-treated analysis sets accounting for treatment group crossover at the index procedure and over time. The effect of paclitaxel dose and baseline covariates were also evaluated. FINDINGS: A total of 2666 participants were included with a median follow-up of 4·9 years. No significant increase in deaths was observed for patients treated with paclitaxel-coated devices. This was true in the ITT analysis (hazard ratio [HR] 1·14, 95% CI 0·93-1·40), the as-treated analysis (HR 1·13, 95% CI 0·92-1·39), and in two crossover analyses: 1·07 (0·87-1·31) when late crossovers were censored and 1·04 (0·84-1·28) when crossovers were analysed from the date of paclitaxel exposure. There was no significant effect of paclitaxel dose on mortality risk. INTERPRETATION: This meta-analysis found no association between paclitaxel-coated device exposure and risk of death, providing reassurance to patients, physicians, and regulators on the safety of paclitaxel-coated devices. FUNDING: Becton Dickinson, Boston Scientific, Cook, Medtronic, Philips, Surmodics, and TriReme Medical.


Assuntos
Fármacos Cardiovasculares , Doença Arterial Periférica , Humanos , Paclitaxel/efeitos adversos , Doença Arterial Periférica/tratamento farmacológico , Artéria Femoral , Fatores de Tempo , Boston , Resultado do Tratamento , Materiais Revestidos Biocompatíveis , Fármacos Cardiovasculares/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
J Vasc Surg ; 79(3): 695-703, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939746

RESUMO

OBJECTIVE: The optimal management of patients with asymptomatic carotid stenosis (AsxCS) is enduringly controversial. We updated our 2021 Expert Review and Position Statement, focusing on recent advances in the diagnosis and management of patients with AsxCS. METHODS: A systematic review of the literature was performed up to August 1, 2023, using PubMed/PubMed Central, EMBASE and Scopus. The following keywords were used in various combinations: "asymptomatic carotid stenosis," "carotid endarterectomy" (CEA), "carotid artery stenting" (CAS), and "transcarotid artery revascularization" (TCAR). Areas covered included (i) improvements in best medical treatment (BMT) for patients with AsxCS and declining stroke risk, (ii) technological advances in surgical/endovascular skills/techniques and outcomes, (iii) risk factors, clinical/imaging characteristics and risk prediction models for the identification of high-risk AsxCS patient subgroups, and (iv) the association between cognitive dysfunction and AsxCS. RESULTS: BMT is essential for all patients with AsxCS, regardless of whether they will eventually be offered CEA, CAS, or TCAR. Specific patient subgroups at high risk for stroke despite BMT should be considered for a carotid revascularization procedure. These patients include those with severe (≥80%) AsxCS, transcranial Doppler-detected microemboli, plaque echolucency on Duplex ultrasound examination, silent infarcts on brain computed tomography or magnetic resonance angiography scans, decreased cerebrovascular reserve, increased size of juxtaluminal hypoechoic area, AsxCS progression, carotid plaque ulceration, and intraplaque hemorrhage. Treatment of patients with AsxCS should be individualized, taking into consideration individual patient preferences and needs, clinical and imaging characteristics, and cultural, ethnic, and social factors. Solid evidence supporting or refuting an association between AsxCS and cognitive dysfunction is lacking. CONCLUSIONS: The optimal management of patients with AsxCS should include BMT for all individuals and a prophylactic carotid revascularization procedure (CEA, CAS, or TCAR) for some asymptomatic patient subgroups, additionally taking into consideration individual patient needs and preference, clinical and imaging characteristics, social and cultural factors, and the available stroke risk prediction models. Future studies should investigate the association between AsxCS with cognitive function and the role of carotid revascularization procedures in the progression or reversal of cognitive dysfunction.


Assuntos
Estenose das Carótidas , Endarterectomia das Carótidas , Procedimentos Endovasculares , Acidente Vascular Cerebral , Humanos , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Medição de Risco , Resultado do Tratamento , Endarterectomia das Carótidas/efeitos adversos , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Procedimentos Endovasculares/efeitos adversos , Stents/efeitos adversos , Estudos Retrospectivos
8.
J Vasc Surg ; 79(2): 420-435.e1, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37944771

RESUMO

OBJECTIVE: Despite the publication of various national/international guidelines, several questions concerning the management of patients with asymptomatic (AsxCS) and symptomatic (SxCS) carotid stenosis remain unanswered. The aim of this international, multi-specialty, expert-based Delphi Consensus document was to address these issues to help clinicians make decisions when guidelines are unclear. METHODS: Fourteen controversial topics were identified. A three-round Delphi Consensus process was performed including 61 experts. The aim of Round 1 was to investigate the differing views and opinions regarding these unresolved topics. In Round 2, clarifications were asked from each participant. In Round 3, the questionnaire was resent to all participants for their final vote. Consensus was reached when ≥75% of experts agreed on a specific response. RESULTS: Most experts agreed that: (1) the current periprocedural/in-hospital stroke/death thresholds for performing a carotid intervention should be lowered from 6% to 4% in patients with SxCS and from 3% to 2% in patients with AsxCS; (2) the time threshold for a patient being considered "recently symptomatic" should be reduced from the current definition of "6 months" to 3 months or less; (3) 80% to 99% AsxCS carries a higher risk of stroke compared with 60% to 79% AsxCS; (4) factors beyond the grade of stenosis and symptoms should be added to the indications for revascularization in AsxCS patients (eg, plaque features of vulnerability and silent infarctions on brain computed tomography scans); and (5) shunting should be used selectively, rather than always or never. Consensus could not be reached on the remaining topics due to conflicting, inadequate, or controversial evidence. CONCLUSIONS: The present international, multi-specialty expert-based Delphi Consensus document attempted to provide responses to several unanswered/unresolved issues. However, consensus could not be achieved on some topics, highlighting areas requiring future research.


Assuntos
Estenose das Carótidas , Acidente Vascular Cerebral , Humanos , Estenose das Carótidas/diagnóstico , Estenose das Carótidas/diagnóstico por imagem , Consenso , Técnica Delphi , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/etiologia , Constrição Patológica
9.
BJU Int ; 133(1): 96-103, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37828739

RESUMO

OBJECTIVES: To describe the contemporary evolution of day-case bladder outflow obstruction (BOO) surgery in England and to profile day-case BOO surgery practices across England in terms of the types of operation performed and their safety profiles. MATERIALS AND METHODS: This was a retrospective observational analysis of Hospital Episode Statistics and UK Office for National Statistics data. All 111 043 recorded operations across 117 hospital trusts over 66 months, from 1 January 2017 to 30 June 2022, were obtained. Operations were identified as one of: transurethral resection of prostate (TURP); laser ablation or enucleation; vapour therapy; prostatic urethral lift (PUL); or bladder neck incision. Monthly day-case rate trends were plotted across the study period. Descriptive data, day-case rates and 30-day hospital readmissions were analysed for each operation type. Multilevel regression modelling with mixed effects was performed to determine whether day-case surgery was associated with higher 30-day hospital readmissions. RESULTS: Day-case patients were younger, with fewer comorbidities. Time series analysis showed a linear day-case rate increase from 8.3% (January 2017) to 21.0% (June 2022). Day-case rates improved for 92/117 trusts in 2021/2022 compared with 2017. Three of the six trusts with the highest day-case rates performed predominantly day-case TURP, and the other three laser surgery. Nationally, PUL and vapour surgery had the highest day-case rates (80.9% and 38.1%). Most inpatient operations were TURP. Multilevel regression modelling found reduced odds of 30-day readmission after day-case BOO surgery (all operations pooled), no difference for day-case vs inpatient TURP, and reduced odds following day-case LASER operations. CONCLUSIONS: The day-case rates for BOO surgery have linearly increased. Minimally invasive surgical technologies are commonly performed as day cases, whereas high day-case rates for TURP and for laser ablation operations are seen in a minority of hospitals. Day-case pathways to treat BOO can be safely developed irrespective of operative modality.


Assuntos
Hiperplasia Prostática , Ressecção Transuretral da Próstata , Obstrução do Colo da Bexiga Urinária , Masculino , Humanos , Hiperplasia Prostática/cirurgia , Hiperplasia Prostática/complicações , Bexiga Urinária/cirurgia , Próstata/cirurgia , Obstrução do Colo da Bexiga Urinária/etiologia , Obstrução do Colo da Bexiga Urinária/cirurgia , Resultado do Tratamento
10.
BJU Int ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637952

RESUMO

The Getting It Right First Time (GIRFT) programme is a quality improvement initiative covering the National Health Service in England. The programme aims to standardise clinical practices and improve patient and system level outcomes by utilising data-driven insights and clinically-led recommendations. There are GIRFT workstreams for every medical and surgical specialty, including urology. Defining features of the GIRFT methodology are that it is clinically led by experienced clinicians, data-driven, and specialty specific. Each specialty workstream conducts deep-dive visits to every hospital, analysing performance data and engaging with clinicians and management to identify and share improvement priorities. For urology, GIRFT has completed deep-dive visits and published reports outlining priority areas for development. Reports include recommendations pertaining to streamlining care pathways, reducing the acuity of care environments, enhancing emergency services, optimising utilisation of outpatient services, and workforce training and utilisation. The GIRFT academy provides guides for implementing best practices specific to priority areas of care. These include important disease pathways, and GIRFT-advocated innovations such as urology investigation units and urology area networks. GIRFT offers clinical transformation, cost reduction, equity in access to care, and leaner models of care that are often more environmentally sustainable. Evaluation efforts of the programme have focussed on assessing the adoption of GIRFT recommendations, understanding barriers to change, and modelling the climate impact of advocated practices.

11.
J Int Neuropsychol Soc ; : 1-11, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38766814

RESUMO

OBJECTIVE: Human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND) prevalence is expected to increase in East Africa as treatment coverage increases, survival improves, and this population ages. This study aimed to better understand the current cognitive phenotype of this newly emergent population of older combination antiretroviral therapy (cART)-treated people living with HIV (PLWH), in which current screening measures lack accuracy. This will facilitate the refinement of HAND cognitive screening tools for this setting. METHOD: This is a secondary analysis of 253 PLWH aged ≥50 years receiving standard government HIV clinic follow-up in Kilimanjaro, Tanzania. They were evaluated with a detailed locally normed low-literacy neuropsychological battery annually on three occasions and a consensus panel diagnosis of HAND by Frascati criteria based on clinical evaluation and collateral history. RESULTS: Tests of verbal learning and memory, categorical verbal fluency, visual memory, and visuoconstruction had an area under the receiver operating characteristic curve >0.7 for symptomatic HAND (s-HAND) (0.70-0.72; p < 0.001 for all tests). Tests of visual memory, verbal learning with delayed recall and recognition memory, psychomotor speed, language comprehension, and categorical verbal fluency were independently associated with s-HAND in a logistic mixed effects model (p < 0.01 for all). Neuropsychological impairments varied by educational background. CONCLUSIONS: A broad range of cognitive domains are affected in older, well-controlled, East African PLWH, including those not captured in widely used screening measures. It is possible that educational background affects the observed cognitive impairments in this setting. Future screening measures for similar populations should consider assessment of visual memory, verbal learning, language comprehension, and executive and motor function.

12.
Brain ; 146(6): 2389-2398, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36415957

RESUMO

More than half of adults with epilepsy undergoing resective epilepsy surgery achieve long-term seizure freedom and might consider withdrawing antiseizure medications. We aimed to identify predictors of seizure recurrence after starting postoperative antiseizure medication withdrawal and develop and validate predictive models. We performed an international multicentre observational cohort study in nine tertiary epilepsy referral centres. We included 850 adults who started antiseizure medication withdrawal following resective epilepsy surgery and were free of seizures other than focal non-motor aware seizures before starting antiseizure medication withdrawal. We developed a model predicting recurrent seizures, other than focal non-motor aware seizures, using Cox proportional hazards regression in a derivation cohort (n = 231). Independent predictors of seizure recurrence, other than focal non-motor aware seizures, following the start of antiseizure medication withdrawal were focal non-motor aware seizures after surgery and before withdrawal [adjusted hazard ratio (aHR) 5.5, 95% confidence interval (CI) 2.7-11.1], history of focal to bilateral tonic-clonic seizures before surgery (aHR 1.6, 95% CI 0.9-2.8), time from surgery to the start of antiseizure medication withdrawal (aHR 0.9, 95% CI 0.8-0.9) and number of antiseizure medications at time of surgery (aHR 1.2, 95% CI 0.9-1.6). Model discrimination showed a concordance statistic of 0.67 (95% CI 0.63-0.71) in the external validation cohorts (n = 500). A secondary model predicting recurrence of any seizures (including focal non-motor aware seizures) was developed and validated in a subgroup that did not have focal non-motor aware seizures before withdrawal (n = 639), showing a concordance statistic of 0.68 (95% CI 0.64-0.72). Calibration plots indicated high agreement of predicted and observed outcomes for both models. We show that simple algorithms, available as graphical nomograms and online tools (predictepilepsy.github.io), can provide probabilities of seizure outcomes after starting postoperative antiseizure medication withdrawal. These multicentre-validated models may assist clinicians when discussing antiseizure medication withdrawal after surgery with their patients.


Assuntos
Epilepsias Parciais , Epilepsia Generalizada , Epilepsia , Humanos , Adulto , Anticonvulsivantes/efeitos adversos , Recidiva Local de Neoplasia/tratamento farmacológico , Epilepsia/tratamento farmacológico , Epilepsia/cirurgia , Convulsões/tratamento farmacológico , Epilepsia Generalizada/tratamento farmacológico
13.
Artigo em Inglês | MEDLINE | ID: mdl-38682154

RESUMO

Comments are provided on the recent paper by Ebadi et al. [3], which demonstrates that the formulated model that was solved contains misconceptions or errors that render the work unsuitable for describing the evolution of interfacial areas in two-fluid porous medium systems. The need for kinematic equations is described and components of a theoretically consistent approach are summarized.

14.
Arch Orthop Trauma Surg ; 144(3): 1129-1137, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38206447

RESUMO

PURPOSE: This study aimed to identify factors associated with poorer patient outcomes for lumbar decompression and/or discectomy (PLDD). METHODS: We extracted data from the Hospital Episodes Statistics database for the 5 years from 1st April 2014 to 31st March 2019. Patients undergoing an elective one- or two-level PLDD aged ≥ 17 years and without evidence of revision surgery during the index stay were included. The primary patient outcome measure was readmission within 90 days post-discharge. RESULTS: Data for 93,813 PLDDs across 111 hospital trusts were analysed. For the primary outcome, greater age [< 40 years vs 70-79 years odds ratio (OR) 1.28 (95% confidence interval (CI) 1.14 to 1.42), < 40 years vs ≥ 80 years OR 2.01 (95% CI 1.76-2.30)], female sex [OR 1.09 (95% CI 1.02-1.16)], surgery over two spinal levels [OR 1.16 (95% CI 1.06-1.26)] and the comorbidities chronic pulmonary disease, connective tissue disease, liver disease, diabetes, hemi/paraplegia, renal disease and cancer were all associated with emergency readmission within 90 days. Other outcomes studied had a similar pattern of associations. CONCLUSIONS: A high-throughput PLDD pathway will not be suitable for all patients. Extra care should be taken for patients aged ≥ 70 years, females, patients undergoing surgery over two spinal levels and those with specific comorbidities or generalised frailty.


Assuntos
Assistência ao Convalescente , Alta do Paciente , Humanos , Feminino , Discotomia , Coluna Vertebral/cirurgia , Descompressão Cirúrgica , Vértebras Lombares/cirurgia , Estudos Retrospectivos
15.
Plant Physiol ; 188(4): 2228-2240, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-34894269

RESUMO

Plasma membrane (PM) H+-ATPase in guard cells is activated by phosphorylation of the penultimate residue, threonine (Thr), in response to blue and red light, promoting stomatal opening. Previous in vitro biochemical investigation suggested that Mg2+- and Mn2+-dependent membrane-localized type 2C protein phosphatase (PP2C)-like activity mediates the dephosphorylation of PM H+-ATPase in guard cells. PP2C clade D (PP2C.D) was later demonstrated to be involved in PM H+-ATPase dephosphorylation during auxin-induced cell expansion in Arabidopsis (Arabidopsis thaliana). However, it is unclear whether PP2C.D phosphatases are involved in PM H+-ATPase dephosphorylation in guard cells. Transient expression experiments using Arabidopsis mesophyll cell protoplasts revealed that all PP2C.D isoforms dephosphorylate the endogenous PM H+-ATPase. We further analyzed PP2C.D6/8/9, which display higher expression levels than other isoforms in guard cells, observing that pp2c.d6, pp2c.d8, and pp2c.d9 single mutants showed similar light-induced stomatal opening and phosphorylation status of PM H+-ATPase in guard cells as Col-0. In contrast, the pp2c.d6/9 double mutant displayed wider stomatal apertures and greater PM H+-ATPase phosphorylation in response to blue light, but delayed dephosphorylation of PM H+-ATPase in guard cells; the pp2c.d6/8/9 triple mutant showed similar phenotypes to those of the pp2c.d6/9 double mutant. Taken together, these results indicate that PP2C.D6 and PP2C.D9 redundantly mediate PM H+-ATPase dephosphorylation in guard cells. Curiously, unlike auxin-induced cell expansion in seedlings, auxin had no effect on the phosphorylation status of PM H+-ATPase in guard cells.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Membrana Celular/metabolismo , Luz , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Fosforilação , Proteína Fosfatase 2C/metabolismo , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo
16.
J Neurovirol ; 29(4): 425-439, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37227670

RESUMO

Studies of depression and its outcomes in older people living with HIV (PLWH) are currently lacking in sub-Saharan Africa. This study aims to investigate the prevalence of psychiatric disorders in PLWH aged ≥ 50 years in Tanzania focussing on prevalence and 2-year outcomes of depression. PLWH aged ≥ 50 were systematically recruited from an outpatient clinic and assessed using the Mini-International Neuropsychiatric Interview (MINI). Neurological and functional impairment was assessed at year 2 follow-up. At baseline, 253 PLWH were recruited (72.3% female, median age 57, 95.5% on cART). DSM-IV depression was highly prevalent (20.9%), whereas other DSM-IV psychiatric disorders were uncommon. At follow-up (n = 162), incident cases of DSM-IV depression decreased from14.2 to 11.1% (χ2: 2.48, p = 0.29); this decline was not significant. Baseline depression was associated with increased functional and neurological impairment. At follow-up, depression was associated with negative life events (p = 0.001), neurological impairment (p < 0.001), and increased functional impairment (p = 0.018), but not with HIV and sociodemographic factors. In this setting, depression appears highly prevalent and associated with poorer neurological and functional outcomes and negative life events. Depression may be a future intervention target.


Assuntos
Infecções por HIV , Humanos , Adulto , Feminino , Idoso , Masculino , Estudos Longitudinais , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Depressão/epidemiologia , Prevalência , Tanzânia/epidemiologia
17.
Mov Disord ; 38(7): 1209-1222, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37212361

RESUMO

BACKGROUND: Cerebral dopamine neurotrophic factor (CDNF) is an unconventional neurotrophic factor that protects dopamine neurons and improves motor function in animal models of Parkinson's disease (PD). OBJECTIVE: The primary objectives of this study were to assess the safety and tolerability of both CDNF and the drug delivery system (DDS) in patients with PD of moderate severity. METHODS: We assessed the safety and tolerability of monthly intraputamenal CDNF infusions in patients with PD using an investigational DDS, a bone-anchored transcutaneous port connected to four catheters. This phase 1 trial was divided into a placebo-controlled, double-blind, 6-month main study followed by an active-treatment 6-month extension. Eligible patients, aged 35 to 75 years, had moderate idiopathic PD for 5 to 15 years and Hoehn and Yahr score ≤ 3 (off state). Seventeen patients were randomized to placebo (n = 6), 0.4 mg CDNF (n = 6), or 1.2 mg CDNF (n = 5). The primary endpoints were safety and tolerability of CDNF and DDS and catheter implantation accuracy. Secondary endpoints were measures of PD symptoms, including Unified Parkinson's Disease Rating Scale, and DDS patency and port stability. Exploratory endpoints included motor symptom assessment (PKG, Global Kinetics Pty Ltd, Melbourne, Australia) and positron emission tomography using dopamine transporter radioligand [18 F]FE-PE2I. RESULTS: Drug-related adverse events were mild to moderate with no difference between placebo and treatment groups. No severe adverse events were associated with the drug, and device delivery accuracy met specification. The severe adverse events recorded were associated with the infusion procedure and did not reoccur after procedural modification. There were no significant changes between placebo and CDNF treatment groups in secondary endpoints between baseline and the end of the main and extension studies. CONCLUSIONS: Intraputamenally administered CDNF was safe and well tolerated, and possible signs of biological response to the drug were observed in individual patients. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Doença de Parkinson , Animais , Doença de Parkinson/tratamento farmacológico , Dopamina , Fatores de Crescimento Neural/fisiologia , Fatores de Crescimento Neural/uso terapêutico , Neurônios Dopaminérgicos , Sistemas de Liberação de Medicamentos , Método Duplo-Cego
18.
Catheter Cardiovasc Interv ; 101(7): 1203-1213, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37070459

RESUMO

BACKGROUND: Permanent pacemaker implantation (PPI) after transcatheter aortic valve implantation (TAVI) is associated with higher risk of mortality and rehospitalization for heart failure. Efforts to prevent conduction abnormalities (CA) requiring PPI after TAVI should be made. The membranous septum (MS) length and its interaction with implantation depth (ID-ΔMSID) could provide useful information about the risk of CA/PPI following TAVI. OBJECTIVES: To identify MS length and ΔMSID as predictors of CA/PPI following TAVI. METHODS: Study-level meta-analysis of studies published by September 30, 2022. RESULTS: Eighteen studies met our eligibility including 5740 patients. Shorter MS length was associated with a significantly higher risk of CA/PPI (per 1 mm decrease: odds ratio [OR] 1.60, 95% confidence interval [CI] 1.28-1.99, p < 0.001). Similarly, lower ΔMSID was associated with a significantly higher risk of CA/PPI (per 1 mm decrease: OR 1.75, 95% CI 1.32-2.31, p < 0.001). Meta-regression analyses revealed a statistically significant modulation of the effect of shorter MS length and lower ΔMSID on the outcome (CA/PPI) by balloon postdilatation (positive regression coefficients with p < 0.001); with increasing use of balloon postdilatation, the effect of shorter MS length and lower ΔMSID on the outcome increased. MS length and ΔMSID demonstrated excellent discriminative abilities, with diagnostic ORs equaling 9.49 (95% CI 4.73-19.06), and 7.19 (95% CI 3.31-15.60), respectively. CONCLUSION: Considering that short MS length and low ΔMSID are associated with higher risk of CA and PPI, we should include measurement of MS length in the pre-TAVI planning with MDCT and try to establish optimal ID values before the procedure to avoid CA/PPI.


Assuntos
Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Marca-Passo Artificial , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Fatores de Risco , Resultado do Tratamento , Tomografia Computadorizada por Raios X , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia
19.
Alzheimer Dis Assoc Disord ; 37(3): 229-236, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37561952

RESUMO

OBJECTIVES: The burden of dementia is increasing in sub-Saharan Africa (SSA), but there are limited epidemiological data on dementia in SSA. This study investigated the prevalence and associations of dementia in older adults (less than 60 y) attending the outpatient department of Mount Meru Hospital in Tanzania. METHODS: This one-phase cross-sectional study screened a sample using the Identification of Dementia in Elderly Africans (IDEA) cognitive screening tool. Those that screened as having possible and probable dementia were further assessed, and diagnosis of dementia was made according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Demographic and risk factor data were collected. RESULTS: Within those screened, 57/1141 (5.0%) (95% CI: 3.7-6.3) had dementia. Female sex [odds ratio (OR)=2.778, 95% CI: 1.074-7.189], having never attended school (OR=6.088, 95% CI: 1.360-27.256), alcohol (U/wk) (OR=1.080, 95% CI: 1.016-1.149), uncorrected visual impairment (OR=4.260, 95% CI: 1.623-11.180), body mass index <18.5 kg/m 2 (OR=6.588, 95% CI: 2.089-20.775), and stroke (OR=15.790, 95% CI: 3.48-74.475) were found to be significantly, independently associated with dementia. CONCLUSIONS: The prevalence of dementia in this population is similar to a recent community-based rate in Tanzania and lower than a hospital-based rate in Senegal. This is the first time the association between visual impairment and dementia has been reported in SSA. Other associations are in keeping with previous literature.


Assuntos
Demência , Humanos , Feminino , Idoso , Demência/diagnóstico , Tanzânia/epidemiologia , Prevalência , Estudos Transversais , Fatores de Risco , Transtornos da Visão
20.
Brain ; 145(5): 1584-1597, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35262656

RESUMO

There has been substantial progress in the development of regenerative medicine strategies for CNS disorders over the last decade, with progression to early clinical studies for some conditions. However, there are multiple challenges along the translational pipeline, many of which are common across diseases and pertinent to multiple donor cell types. These include defining the point at which the preclinical data are sufficiently compelling to permit progression to the first clinical studies; scaling-up, characterization, quality control and validation of the cell product; design, validation and approval of the surgical device; and operative procedures for safe and effective delivery of cell product to the brain. Furthermore, clinical trials that incorporate principles of efficient design and disease-specific outcomes are urgently needed (particularly for those undertaken in rare diseases, where relatively small cohorts are an additional limiting factor), and all processes must be adaptable in a dynamic regulatory environment. Here we set out the challenges associated with the clinical translation of cell therapy, using Huntington's disease as a specific example, and suggest potential strategies to address these challenges. Huntington's disease presents a clear unmet need, but, importantly, it is an autosomal dominant condition with a readily available gene test, full genetic penetrance and a wide range of associated animal models, which together mean that it is a powerful condition in which to develop principles and test experimental therapeutics. We propose that solving these challenges in Huntington's disease would provide a road map for many other neurological conditions. This white paper represents a consensus opinion emerging from a series of meetings of the international translational platforms Stem Cells for Huntington's Disease and the European Huntington's Disease Network Advanced Therapies Working Group, established to identify the challenges of cell therapy, share experience, develop guidance and highlight future directions, with the aim to expedite progress towards therapies for clinical benefit in Huntington's disease.


Assuntos
Doença de Huntington , Doenças Neurodegenerativas , Animais , Encéfalo/metabolismo , Terapia Baseada em Transplante de Células e Tecidos , Humanos , Doença de Huntington/genética , Doença de Huntington/metabolismo , Doença de Huntington/terapia , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/terapia
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