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1.
Nat Neurosci ; 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39187705

RESUMEN

Proteomics can shed light on the dynamic and multifaceted alterations in neurodegenerative disorders like Alzheimer disease (AD). Combining radioligands measuring ß-amyloid (Aß) plaques and tau tangles with cerebrospinal fluid proteomics, we uncover molecular events mirroring different stages of AD pathology in living humans. We found 127 differentially abundant proteins (DAPs) across the AD spectrum. The strongest Aß-related proteins were mainly expressed in glial cells and included SMOC1 and ITGAM. A dozen proteins linked to ATP metabolism and preferentially expressed in neurons were independently associated with tau tangle load and tau accumulation. Only 20% of the DAPs were also altered in other neurodegenerative diseases, underscoring AD's distinct proteome. Two co-expression modules related, respectively, to protein metabolism and microglial immune response encompassed most DAPs, with opposing, staggered trajectories along the AD continuum. We unveil protein signatures associated with Aß and tau proteinopathy in vivo, offering insights into complex neural responses and potential biomarkers and therapeutics targeting different disease stages.

2.
Int J Chron Obstruct Pulmon Dis ; 19: 1879-1892, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39185393

RESUMEN

Purpose: This study evaluated the long-term safety of roflumilast in patients with chronic obstructive pulmonary disease or chronic bronchitis using electronic healthcare databases from Germany, Norway, Sweden, and the United States (US). Patients and Methods: The study population consisted of patients aged ≥40 years who had been exposed to roflumilast and a matched cohort unexposed to roflumilast. The matching was based on sex, age, calendar year of cohort entry date (2010-2011, 2012, or 2013), and a propensity score that included variables such as demographics, markers of chronic obstructive pulmonary disease (COPD) severity and morbidity, and comorbidities. In comparison to the unexposed matched cohort (never use), three exposure definitions were used for the exposed matched cohort: ever use, use status (current, recent, past use), and cumulative duration of use. The main outcome was 5-year all-cause mortality. Cox regression models were used to estimate crude and adjusted hazard ratios (HRs) and 95% confidence intervals (CI). Results: 112,541 unexposed and 23,239 exposed patients across countries were included. Some variables remained unbalanced after matching, indicating higher COPD disease severity among the exposed patients. Adjusted HRs of 5-year all-cause mortality for "ever use" of roflumilast, compared to "never use", were 1.12 (95% CI, 1.08-1.17) in Germany, 1.00 (95% CI, 0.92-1.08) in Norway, 0.98 (95% CI, 0.92-1.04) in Sweden, and 1.16 (95% CI, 1.12-1.20) in the US. Compared to never users, there was a decrease in 5-year mortality risk observed among "current users" in Germany (HR: 0.93, 95% CI: 0.88-0.98), Norway (HR: 0.77, 95% CI: 0.67-0.87), and Sweden (HR: 0.80, 95% CI: 0.73-0.88). Conclusion: There was no observed increase in 5-year mortality risk with the use of roflumilast in Sweden or Norway. A small increase in 5-year mortality risk was observed in Germany and the US in the ever versus never comparison, likely due to residual confounding by indication.


Asunto(s)
Aminopiridinas , Benzamidas , Ciclopropanos , Bases de Datos Factuales , Inhibidores de Fosfodiesterasa 4 , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Ciclopropanos/efectos adversos , Ciclopropanos/uso terapéutico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Masculino , Femenino , Inhibidores de Fosfodiesterasa 4/efectos adversos , Inhibidores de Fosfodiesterasa 4/uso terapéutico , Benzamidas/efectos adversos , Benzamidas/uso terapéutico , Persona de Mediana Edad , Anciano , Aminopiridinas/uso terapéutico , Aminopiridinas/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Factores de Riesgo , Estados Unidos/epidemiología , Bronquitis Crónica/tratamiento farmacológico , Bronquitis Crónica/mortalidad , Bronquitis Crónica/epidemiología , Medición de Riesgo , Alemania , Adulto , Suecia/epidemiología , Anciano de 80 o más Años
3.
J Stroke Cerebrovasc Dis ; 33(10): 107913, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39098362

RESUMEN

BACKGROUND: Hemorrhagic transformation (HT) and cerebral edema (CED) are both major complications following ischemic stroke, but few studies have evaluated their overlap. We evaluated the frequency and predictors of CED/HT overlap and whether their co-occurrence impacts functional outcome more than each in isolation. METHODS: 892 stroke patients enrolled in a prospective study had follow-up CT imaging evaluated for HT and CED; the latter was quantified using the ratio of hemispheric CSF volumes (with hemispheric CSF ratio < 0.90 used as the CED threshold). The interaction between HT and CED on functional outcome (using modified Rankin Scale at 3 months) was compared to that for each condition separately. RESULTS: Among the 275 (31%) who developed HT, 233 (85%) manifested hemispheric CSF ratio < 0.9 (CED/HT), with this overlap group representing half of the 475 with measurable CED. Higher baseline NIHSS scores and larger infarct volumes were observed in the CED/HT group compared with those with CED or HT alone. Functional outcome was worse in those with CED/HT [median mRS 3 (IQR 2-5)] than those with CED [median 2 (IQR 1-4)] or HT alone [median 1 (IQR 0-2), p < 0.0001]. Overlap of CED/HT independently predicted worse outcome [OR 1.89 (95% CI: 1.12-3.18), p = 0.02] while HT did not; however, CED/HT was no longer associated with worse outcome after adjusting for severity of CED [adjusted OR 0.35 (95% CI: 0.23, 0.51) per 0.21 lower hemispheric CSF ratio, p < 0.001]. CONCLUSIONS: Most stroke patients with HT also have measurable CED. The co-occurrence of CED and HT occurs in larger and more severe strokes and is associated with worse functional outcome, although this is driven by greater severity of stroke-related edema in those with HT.

4.
Proc Natl Acad Sci U S A ; 121(31): e2402755121, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39042673

RESUMEN

The precise assembly of a functional nervous system relies on axon guidance cues. Beyond engaging their cognate receptors and initiating signaling cascades that modulate cytoskeletal dynamics, guidance cues also bind components of the extracellular matrix, notably proteoglycans, yet the role and mechanisms of these interactions remain poorly understood. We found that Drosophila secreted semaphorins bind specifically to glycosaminoglycan (GAG) chains of proteoglycans, showing a preference based on the degree of sulfation. Structural analysis of Sema2b unveiled multiple GAG-binding sites positioned outside canonical plexin-binding site, with the highest affinity binding site located at the C-terminal tail, characterized by a lysine-rich helical arrangement that appears to be conserved across secreted semaphorins. In vivo studies revealed a crucial role of the Sema2b C-terminal tail in specifying the trajectory of olfactory receptor neurons. We propose that secreted semaphorins tether to the cell surface through interactions with GAG chains of proteoglycans, facilitating their presentation to cognate receptors on passing axons.


Asunto(s)
Orientación del Axón , Proteínas de Drosophila , Proteoglicanos , Semaforinas , Transducción de Señal , Animales , Semaforinas/metabolismo , Semaforinas/genética , Proteoglicanos/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Axones/metabolismo , Drosophila melanogaster/metabolismo , Glicosaminoglicanos/metabolismo , Sitios de Unión , Unión Proteica , Neuronas Receptoras Olfatorias/metabolismo
5.
medRxiv ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38947084

RESUMEN

The pathophysiology underlying various manifestations of cerebral small vessel disease (cSVD) remains obscure. Using cerebrospinal fluid proximity extension assays and co-expression network analysis of 2,943 proteins, we found common and distinct proteomic signatures between white matter lesions (WML), microbleeds and infarcts measured in 856 living patients, and validated WML-associated proteins in three additional datasets. Proteins indicative of extracellular matrix dysregulation and vascular remodeling, including ELN, POSTN, CCN2 and MMP12 were elevated across all cSVD manifestations, with MMP12 emerging as an early cSVD indicator. cSVD-associated proteins formed a co-abundance network linked to metabolism and enriched in endothelial and arterial smooth muscle cells, showing elevated levels at early disease manifestations. Later disease stages involved changes in microglial proteins, associated with longitudinal WML progression, and changes in neuronal proteins mediating WML-associated cognitive decline. These findings provide an atlas of novel cSVD biomarkers and a promising roadmap for the next generation of cSVD therapeutics.

6.
Plant Biotechnol J ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38923713

RESUMEN

Developing early maturing lentil has the potential to minimize yield losses, mainly during terminal drought. Whole-genome resequencing (WGRS) based QTL-seq identified the loci governing earliness in lentil. The genetic analysis for maturity duration provided a good fit to 3:1 segregation (F2), indicating earliness as a recessive trait. WGRS of Globe Mutant (late parent), late-flowering, and early-flowering bulks (from RILs) has generated 1124.57, 1052.24 million raw and clean reads, respectively. The QTL-Seq identified three QTLs (LcqDTF3.1, LcqDTF3.2, and LcqDTF3.3) on chromosome 3 having 246244 SNPs and 15577 insertions/deletions (InDels) and 13 flowering pathway genes. Of these, 11 exhibited sequence variations between bulks and validation (qPCR) revealed a significant difference in the expression of nine candidate genes (LcGA20oxG, LcFRI, LcLFY, LcSPL13a, Lcu.2RBY.3g060720, Lcu.2RBY.3g062540, Lcu.2RBY.3g062760, LcELF3a, and LcEMF1). Interestingly, the LcELF3a gene showed significantly higher expression in late-flowering genotype and exhibited substantial involvement in promoting lateness. Subsequently, an InDel marker (I-SP-383.9; LcELF3a gene) developed from LcqDTF3.2 QTL region showed 82.35% PVE (phenotypic variation explained) for earliness. The cloning, sequencing, and comparative analysis of the LcELF3a gene from both parents revealed 23 SNPs and InDels. Interestingly, a 52 bp deletion was recorded in the LcELF3a gene of L4775, predicted to cause premature termination of protein synthesis after 4 missense amino acids beyond the 351st amino acid due to the frameshift during translation. The identified InDel marker holds significant potential for breeding early maturing lentil varieties.

7.
J Phys Chem B ; 128(25): 6049-6058, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38840325

RESUMEN

Lasioglossin-III (LL-III) is a potent broad-spectrum antimicrobial peptide used in diverse antimicrobial applications. In this work, coarse-grained and all-atom molecular dynamics simulation strategies were used in tandem to interpret the molecular mechanisms involved in the interfacial dynamics of LL-III and its recombinant variants during interactions with diverse cell membrane systems. Our results indicate that the membrane charges act as the driving force for initiating the membrane-peptide interactions, while the hydrophobic or van der Waals forces help to reinforce the membrane-peptide bindings. The optimized charge-hydrophobicity ratio of the LL-III peptides helps ensure their high specificity toward bacterial membranes compared to mammalian membrane systems, which also helps explain our experimental observations. Overall, we hope that our work gives new insight into the antimicrobial action of LL-III peptides and that the adopted simulation strategy will help other scientists and engineers extract maximal information from complex molecular simulations using minimal computational power.


Asunto(s)
Péptidos Catiónicos Antimicrobianos , Simulación de Dinámica Molecular , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/metabolismo , Interacciones Hidrofóbicas e Hidrofílicas , Membrana Celular/química , Membrana Celular/metabolismo , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo
8.
iScience ; 27(6): 109994, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38883841

RESUMEN

Mitofusin-2 (MFN2), a large GTPase residing in the mitochondrial outer membrane and mutated in Charcot-Marie-Tooth type 2 disease (CMT2A), is a regulator of mitochondrial fusion and tethering with the ER. The role of MFN2 in mitochondrial transport has however remained elusive. Like MFN2, acetylated microtubules play key roles in mitochondria dynamics. Nevertheless, it is unknown if the α-tubulin acetylation cycle functionally interacts with MFN2. Here, we show that mitochondrial contacts with microtubules are sites of α-tubulin acetylation, which occurs through MFN2-mediated recruitment of α-tubulin acetyltransferase 1 (ATAT1). This activity is critical for MFN2-dependent regulation of mitochondria transport, and axonal degeneration caused by CMT2A MFN2 associated R94W and T105M mutations may depend on the inability to release ATAT1 at sites of mitochondrial contacts with microtubules. Our findings reveal a function for mitochondria in α-tubulin acetylation and suggest that disruption of this activity plays a role in the onset of MFN2-dependent CMT2A.

9.
Artículo en Inglés | MEDLINE | ID: mdl-38716551

RESUMEN

Cancer remains a significant global health challenge, necessitating innovative approaches to enhance the efficacy and specificity of therapeutic interventions while minimizing adverse effects on healthy tissues. Nanotechnology has emerged as a promising avenue in cancer treatment, offering novel strategies for targeted drug delivery. Nanoparticles, liposomes, and polymer-based systems have played pivotal roles in revolutionizing cancer therapy. Nanotechnology possesses unique physicochemical properties, enabling efficient encapsulation of therapeutic agents and controlled and prolonged release at tumour sites. Advancement in formulations using nanotechnology has made it possible to make multifunctional systems that respond to the microenvironment of a tumour by releasing payloads in response to changes in pH, temperature, or enzymes. Stimuli-responsive polymers can release drugs in response to external cues, enabling site-specific drug release and minimizing systemic exposure. This review explores recent studies and preclinical trials that show how nanoparticles, liposomes, and polymerbased systems could be used to treat cancer, discussing challenges such as scalability, regulatory approval, and potential toxicity concerns along with patents published recently.

10.
PLoS One ; 19(5): e0302870, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38776345

RESUMEN

The systematic identification of insertion/deletion (InDel) length polymorphisms from the entire lentil genome can be used to map the quantitative trait loci (QTL) and also for the marker-assisted selection (MAS) for various linked traits. The InDels were identified by comparing the whole-genome resequencing (WGRS) data of two extreme bulks (early- and late-flowering bulk) and a parental genotype (Globe Mutant) of lentil. The bulks were made by pooling 20 extreme recombinant inbred lines (RILs) each, derived by crossing Globe Mutant (late flowering parent) with L4775 (early flowering parent). Finally, 734,716 novel InDels were identified, which is nearly one InDel per 5,096 bp of lentil genome. Furthermore, 74.94% of InDels were within the intergenic region and 99.45% displayed modifier effects. Of these, 15,732 had insertions or deletions of 20 bp or more, making them amenable to the development of PCR-based markers. An InDel marker I-SP-356.6 (chr. 3; position 356,687,623; positioned 174.5 Kb from the LcFRI gene) was identified as having a phenotypic variance explained (PVE) value of 47.7% for earliness when validated in a RIL population. Thus, I-SP-356.6 marker can be deployed in MAS to facilitate the transfer of the earliness trait to other elite late-maturing cultivars. Two InDel markers viz., I-SP-356.6 and I-SP-383.9 (chr. 3; linked to LcELF3a gene) when tested in 9 lentil genotypes differing for maturity duration, clearly distinguished three early (L4775, ILL7663, Precoz) and four late genotypes (Globe Mutant, MFX, L4602, L830). However, these InDels could not be validated in two genotypes (L4717, L4727), suggesting either absence of polymorphism and/or presence of other loci causing earliness. The identified InDel markers can act as valuable tools for MAS for the development of early maturing lentil varieties.


Asunto(s)
Genoma de Planta , Genotipo , Mutación INDEL , Lens (Planta) , Sitios de Carácter Cuantitativo , Lens (Planta)/genética , Lens (Planta)/crecimiento & desarrollo , Marcadores Genéticos , Reacción en Cadena de la Polimerasa/métodos , Mapeo Cromosómico/métodos
11.
Cureus ; 16(3): e56855, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38659517

RESUMEN

Background This study aimed to compare the clinical outcomes of a heparin surface-modified (HSM) hydrophobic acrylic foldable intraocular lens (IOL) (CT LUCIA 601PY) and non-heparin-modified hydrophobic acrylic foldable IOL (AcrySof IQ SN60WF) in diabetic patients undergoing phacoemulsification. Methodology This randomized, single-surgeon, double-masked controlled trial was conducted at Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi. In this randomized controlled trial, 100 eyes of 100 diabetic patients with or without mild-to-moderate diabetic retinopathy were enrolled (HSM IOL, n = 50; non-HSM IOL, n = 50). Outcome measures were aqueous flare, visual acuity, and anterior chamber depth (ACD). These were measured preoperatively as well as one day, one week, one month, three months, six months, and one year postoperatively. Results The HSM IOL group had significantly lower anterior chamber aqueous flare values (photon count/ms) than the non-HSM IOL group on postoperative day one (9.97 ± 5.2 vs. 17.56 ± 11.3, p < 0.001), postoperative week one (11.47 ± 7.78 vs. 17.06 ± 9.4, p = 0.02), and postoperative month three (7.7 ± 4.1 vs. 12.5 ± 5.6, p = 0.004) of phacoemulsification. The corrected distance visual acuity (CDVA) was significantly better in the HSM IOL group on postoperative day one (uncorrected distance visual acuity: p = 0.022; CDVA; p = 0.005), but there was no significant difference at any other follow-ups. ACD was significantly longer in the HSM IOL group at all follow-ups. Conclusions The implantation of HSM IOL resulted in significantly lower inflammatory reactions in the early postoperative period in diabetics.

12.
J Neurointerv Surg ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637151

RESUMEN

BACKGROUND: Cerebral edema (CED) is associated with poorer outcome in patients with acute ischemic stroke (AIS). The aim of the study was to investigate the factors contributing to greater early CED formation in patients with AIS who underwent endovascular therapy (EVT) and its association with functional outcome. METHODS: We conducted a multicenter cohort study of patients with an anterior circulation AIS undergoing EVT. The volume of cerebrospinal fluid (CSF) was extracted from baseline and 24-hour follow-up CT using an automated algorithm. The severity of CED was quantified by the percentage reduction in CSF volume between CT scans (∆CSF). The primary endpoint was a shift towards an unfavorable outcome, assessed by modified Rankin Scale (mRS) score at 3 months. Multivariable ordinal logistic regression analyses were performed. The ∆CSF threshold that predicted unfavorable outcome was selected using receiver operating characteristic curve analysis. RESULTS: We analyzed 201 patients (mean age 72.7 years, 47.8% women) in whom CED was assessable for 85.6%. Higher systolic blood pressure during EVT and failure to achieve modified Thrombolysis In Cerebral Infarction (mTICI) 3 were found to be independent predictors of greater CED. ∆CSF was independently associated with the probability of a one-point worsening in the mRS score (common odds ratio (cOR) 1.05, 95% CI 1.03 to 1.08) after adjusting for age, baseline mRS, National Institutes of Health Stroke Scale (NIHSS), and number of passes. Displacement of more than 25% of CSF was associated with an unfavorable outcome (OR 6.09, 95% CI 3.01 to 12.33) and mortality (OR 6.72, 95% CI 2.94 to 15.32). CONCLUSIONS: Early CED formation in patients undergoing EVT was affected by higher blood pressure and incomplete reperfusion. The extent of early CED, measured by automated ∆CSF, was associated with worse outcomes.

13.
Neurocrit Care ; 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38580801

RESUMEN

BACKGROUND: Hypoxemia is the main modifiable factor preventing lungs from being transplanted from organ donors after brain death. One major contributor to impaired oxygenation in patients with brain injury is atelectasis. Apnea testing, an integral component of brain death declaration, promotes atelectasis and can worsen hypoxemia. In this study, we tested whether performing a recruitment maneuver (RM) after apnea testing could mitigate hypoxemia and atelectasis. METHODS: During the study period, an RM (positive end-expiratory pressure of 15 cm H2O for 15 s then 30 cm H2O for 30 s) was performed immediately after apnea testing. We measured partial pressure of oxygen, arterial (PaO2) before and after RM. The primary outcomes were oxygenation (PaO2 to fraction of inspired oxygen [FiO2] ratio) and the severity of radiographic atelectasis (proportion of lung without aeration on computed tomography scans after brain death, quantified using an image analysis algorithm) in those who became organ donors. Outcomes in RM patients were compared with control patients undergoing apnea testing without RM in the previous 2 years. RESULTS: Recruitment maneuver was performed in 54 patients after apnea testing, with a median immediate increase in PaO2 of 63 mm Hg (interquartile range 0-109, p = 0.07). Eighteen RM cases resulted in hypotension, but none were life-threatening. Of this cohort, 37 patients became organ donors, compared with 37 donors who had apnea testing without RM. The PaO2:FiO2 ratio was higher in the RM group (355 ± 129 vs. 288 ± 127, p = 0.03), and fewer had hypoxemia (PaO2:FiO2 ratio < 300 mm Hg, 22% vs. 57%; p = 0.04) at the start of donor management. The RM group showed less radiographic atelectasis (median 6% vs. 13%, p = 0.045). Although there was no difference in lungs transplanted (35% vs. 24%, p = 0.44), both better oxygenation and less atelectasis were associated with a higher likelihood of lungs being transplanted. CONCLUSIONS: Recruitment maneuver after apnea testing reduces hypoxemia and atelectasis in organ donors after brain death. This effect may translate into more lungs being transplanted.

14.
Artículo en Inglés | MEDLINE | ID: mdl-38441025

RESUMEN

Hyperlipidemia, characterized by elevated levels of lipids in the blood, represents a major risk factor for cardiovascular diseases, a leading cause of morbidity and mortality worldwide. Conventional pharmacological interventions have been effective in managing hyperlipidemia, but concerns about side effects and long-term use have prompted interest in alternative approaches, particularly the use of nutraceuticals. This comprehensive review aims to summarize and critically evaluate the current body of knowledge surrounding the role of nutraceuticals in the management of hyperlipidemia. We provide an overview of the different classes of nutraceuticals, including plant sterols, omega-3 fatty acids, soluble fiber, antioxidants, and various herbal extracts, which have been investigated for their lipid-lowering properties. The mechanisms of action of these nutraceuticals are discussed, highlighting their ability to modulate lipid metabolism, reduce oxidative stress, and promote cardiovascular health. Furthermore, we review the results of clinical trials and epidemiological studies that have assessed the efficacy of nutraceutical interventions in lowering cholesterol levels, improving lipid profiles, and reducing the risk of cardiovascular events. In addition to their lipid-lowering effects, we examine the safety profile, dosage recommendations, and potential interactions of nutraceuticals with conventional lipid-lowering medications. We also address the importance of patient adherence to dietary and lifestyle modifications in conjunction with nutraceutical supplementation. While nutraceuticals offer a promising avenue for managing hyperlipidemia, we emphasize the need for further research to establish evidence-based guidelines for their use in clinical practice. Challenges related to standardization, quality control, and regulatory considerations are also discussed. In conclusion, this comprehensive review provides valuable insights into the potential of nutraceuticals as adjunctive or alternative therapies for managing hyperlipidemia. While further research is needed, the accumulating evidence suggests that nutraceuticals can play a valuable role in promoting cardiovascular health and reducing the burden of hyperlipidemia- related diseases.

15.
Elife ; 122024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38502163

RESUMEN

Neurotransmission at synapses is mediated by the fusion and subsequent endocytosis of synaptic vesicle membranes. Actin has been suggested to be required for presynaptic endocytosis but the mechanisms that control actin polymerization and its mode of action within presynaptic nerve terminals remain poorly understood. We combine optical recordings of presynaptic membrane dynamics and ultrastructural analysis with genetic and pharmacological manipulations to demonstrate that presynaptic endocytosis is controlled by actin regulatory diaphanous-related formins mDia1/3 and Rho family GTPase signaling in mouse hippocampal neurons. We show that impaired presynaptic actin assembly in the near absence of mDia1/3 and reduced RhoA activity is partly compensated by hyperactivation of Rac1. Inhibition of Rac1 signaling further aggravates impaired presynaptic endocytosis elicited by loss of mDia1/3. Our data suggest that interdependent mDia1/3-Rho and Rac1 signaling pathways cooperatively act to facilitate synaptic vesicle endocytosis by controlling presynaptic F-actin.


Asunto(s)
Actinas , Proteínas de Unión al GTP rho , Animales , Ratones , Transducción de Señal , Transmisión Sináptica , Endocitosis
16.
J Org Chem ; 89(5): 2873-2884, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38354303

RESUMEN

We have developed the first I2/base-catalyzed regio- and stereoselective intermolecular ß-amidosulfonylation of terminal alkynes using sodium sulfinates and quinoxalinone derivatives. The present methodology is compatible with a broad spectrum of various heterocyclic amides, terminal alkynes, and sodium sulfinates. It provides rapid access to valuable (Z)-ß-amidovinyl sulfones at mild conditions. Moreover, the synthetic application of this methodology was demonstrated by the late-stage functionalization of numerous bioactive molecules.

17.
Agron Sustain Dev ; 44(1): 2, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38161803

RESUMEN

The UK Government has set an ambitious target of achieving a national "net-zero" greenhouse gas economy by 2050. Agriculture is arguably placed at the heart of achieving net zero, as it plays a unique role as both a producer of GHG emissions and a sector that has the capacity via land use to capture carbon (C) when managed appropriately, thus reducing the concentration of carbon dioxide (CO2) in the atmosphere. Agriculture's importance, particularly in a UK-specific perspective, which is also applicable to many other temperate climate nations globally, is that the majority of land use nationwide is allocated to farming. Here, we present a systematic review based on peer-reviewed literature and relevant "grey" reports to address the question "how can the agricultural sector in the UK reduce, or offset, its direct agricultural emissions at the farm level?" We considered the implications of mitigation measures in terms of food security and import reliance, energy, environmental degradation, and value for money. We identified 52 relevant studies covering major foods produced and consumed in the UK. Our findings indicate that many mitigation measures can indeed contribute to net zero through GHG emissions reduction, offsetting, and bioenergy production, pending their uptake by farmers. While the environmental impacts of mitigation measures were covered well within the reviewed literature, corresponding implications regarding energy, food security, and farmer attitudes towards adoption received scant attention. We also provide an open-access, informative, and comprehensive dataset for agri-environment stakeholders and policymakers to identify the most promising mitigation measures. This research is of critical value to researchers, land managers, and policymakers as an interim guideline resource while more quantitative evidence becomes available through the ongoing lab-, field-, and farm-scale trials which will improve the reliability of agricultural sustainability modelling in the future. Supplementary Information: The online version contains supplementary material available at 10.1007/s13593-023-00938-0.

18.
PeerJ ; 12: e16653, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38288464

RESUMEN

Yellow mosaic disease (YMD) remains a major constraint in mungbean (Vigna radiata (L.)) production; while short-duration genotypes offer multiple crop cycles per year and help in escaping terminal heat stress, especially during summer cultivation. A comprehensive genotyping by sequencing (GBS)-based genome-wide association studies (GWAS) analysis was conducted using 132 diverse mungbean genotypes for traits like flowering time, YMD resistance, soil plant analysis development (SPAD) value, trichome density, and leaf area. The frequency distribution revealed a wide range of values for all the traits. GBS studies identified 31,953 high-quality single nucleotide polymorphism (SNPs) across all 11 mungbean chromosomes and were used for GWAS. Structure analysis revealed the presence of two genetically distinct populations based on ΔK. The linkage disequilibrium (LD) varied throughout the chromosomes and at r2 = 0.2, the mean LD decay was estimated as 39.59 kb. Two statistical models, mixed linear model (MLM) and Bayesian-information and Linkage-disequilibrium Iteratively Nested Keyway (BLINK) identified 44 shared SNPs linked with various candidate genes. Notable candidate genes identified include FPA for flowering time (VRADI10G01470; chr. 10), TIR-NBS-LRR for mungbean yellow mosaic India virus (MYMIV) resistance (VRADI09G06940; chr. 9), E3 ubiquitin-protein ligase RIE1 for SPAD value (VRADI07G28100; chr. 11), WRKY family transcription factor for leaf area (VRADI03G06560; chr. 3), and LOB domain-containing protein 21 for trichomes (VRADI06G04290; chr. 6). In-silico validation of candidate genes was done through digital gene expression analysis using Arabidopsis orthologous (compared with Vigna radiata genome). The findings provided valuable insight for marker-assisted breeding aiming for the development of YMD-resistant and early-maturing mungbean varieties.


Asunto(s)
Vigna , Vigna/genética , Estudio de Asociación del Genoma Completo , Genotipo , Teorema de Bayes , Fitomejoramiento
19.
Childs Nerv Syst ; 40(1): 213-218, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37428253

RESUMEN

OBJECTIVE: The fibroneural stalk of an LDM has variable thickness, complexity, and length, which can span 5 to 6 vertebral segments from its skin attachment to its "merge point" with the dorsal spinal cord. Therefore, complete resection may require extensive multi-level laminotomies. In this technical note, a modification of the procedure is presented that avoids long segment laminectomies while ensuring complete excision of long LDM stalks. RESULTS: An illustrative case of resection of LDM is presented using skip laminectomies. The technique ensures complete removal of the stalk, thus reducing the risk of future intradural dermoid development, while at the same time minimizes the risk for delayed kyphotic deformity. CONCLUSIONS: A technique of "skip-hop" proximal and distal short segment laminectomies in cases of LDM optimizes the objectives of complete stalk resection with preservation of spinal integrity.


Asunto(s)
Laminectomía , Médula Espinal , Humanos , Médula Espinal/cirugía , Piel , Columna Vertebral/cirugía
20.
Neurocrit Care ; 40(1): 303-313, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37188885

RESUMEN

BACKGROUND: Cerebral edema has primarily been studied using midline shift or clinical deterioration as end points, which only captures the severe and delayed manifestations of a process affecting many patients with stroke. Quantitative imaging biomarkers that measure edema severity across the entire spectrum could improve its early detection, as well as identify relevant mediators of this important stroke complication. METHODS: We applied an automated image analysis pipeline to measure the displacement of cerebrospinal fluid (ΔCSF) and the ratio of lesional versus contralateral hemispheric cerebrospinal fluid (CSF) volume (CSF ratio) in a cohort of 935 patients with hemispheric stroke with follow-up computed tomography scans taken a median of 26 h (interquartile range 24-31) after stroke onset. We determined diagnostic thresholds based on comparison to those without any visible edema. We modeled baseline clinical and radiographic variables against each edema biomarker and assessed how each biomarker was associated with stroke outcome (modified Rankin Scale at 90 days). RESULTS: The displacement of CSF and CSF ratio were correlated with midline shift (r = 0.52 and - 0.74, p < 0.0001) but exhibited broader ranges. A ΔCSF of greater than 14% or a CSF ratio below 0.90 identified those with visible edema: more than half of the patients with stroke met these criteria, compared with only 14% who had midline shift at 24 h. Predictors of edema across all biomarkers included a higher National Institutes of Health Stroke Scale score, a lower Alberta Stroke Program Early CT score, and lower baseline CSF volume. A history of hypertension and diabetes (but not acute hyperglycemia) predicted greater ΔCSF but not midline shift. Both ΔCSF and a lower CSF ratio were associated with worse outcome, adjusting for age, National Institutes of Health Stroke Scale score, and Alberta Stroke Program Early CT score (odds ratio 1.7, 95% confidence interval 1.3-2.2 per 21% ΔCSF). CONCLUSIONS: Cerebral edema can be measured in a majority of patients with stroke on follow-up computed tomography using volumetric biomarkers evaluating CSF shifts, including in many without visible midline shift. Edema formation is influenced by clinical and radiographic stroke severity but also by chronic vascular risk factors and contributes to worse stroke outcomes.


Asunto(s)
Edema Encefálico , Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular Isquémico/complicaciones , Isquemia Encefálica/complicaciones , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/epidemiología , Edema Encefálico/diagnóstico por imagen , Edema Encefálico/epidemiología , Edema Encefálico/etiología , Incidencia , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/epidemiología , Biomarcadores , Edema/complicaciones , Factores de Riesgo , Resultado del Tratamiento
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