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1.
bioRxiv ; 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38659860

RESUMEN

Wolcott-Rallison Syndrome (WRS) is the most common cause of permanent neonatal diabetes mellitus among consanguineous families. The diabetes associated with WRS is non-autoimmune, insulin-requiring and associated with skeletal dysplasia and growth retardation. The therapeutic options for WRS patients rely on permanent insulin pumping or on invasive transplants of liver and pancreas. WRS has a well identified genetic cause: loss-of-function mutations in the gene coding for an endoplasmic reticulum kinase named PERK (protein kinase R-like ER kinase). Currently, WRS research is facilitated by cellular and rodent models with PERK ablation. While these models have unique strengths, cellular models incompletely replicate the organ/system-level complexity of WRS, and rodents have limited scalability for efficiently screening potential therapeutics. To address these challenges, we developed a new in vivo model of WRS by pharmacologically inhibiting PERK in zebrafish. This small vertebrate displays high fecundity, rapid development of organ systems and is amenable to highly efficient in vivo drug testing. PERK inhibition in zebrafish produced typical WRS phenotypes such as glucose dysregulation, skeletal defects, and impaired development. PERK inhibition in zebrafish also produced broad-spectrum WRS phenotypes such as impaired neuromuscular function, compromised cardiac function and muscular integrity. These results show that zebrafish holds potential as a versatile model to study WRS mechanisms and contribute to the identification of promising therapeutic options for WRS.

2.
Free Radic Biol Med ; 217: 126-140, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38531462

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease in which the death of motor neurons leads to loss of muscle function. Additionally, cognitive and circadian disruptions are common in ALS patients, contributing to disease progression and burden. Most ALS cases are sporadic, and environmental exposures contribute to their aetiology. However, animal models of these sporadic ALS cases are scarce. The small vertebrate zebrafish is a leading organism to model neurodegenerative diseases; previous studies have proposed bisphenol A (BPA) or ß-methylamino-l-alanine (BMAA) exposure to model sporadic ALS in zebrafish, damaging motor neurons and altering motor responses. Here we characterise the face and predictive validity of sporadic ALS models, showing their potential for the mechanistic study of ALS drugs. We phenotypically characterise the BPA and BMAA-induced models, going beyond motor activity and motor axon morphology, to include circadian, redox, proteostasis, and metabolomic phenotypes, and assessing their predictive validity for ALS modelling. BPA or BMAA exposure induced concentration-dependent activity impairments. Also, exposure to BPA but not BMAA induced motor axonopathy and circadian alterations in zebrafish larvae. Our further study of the BPA model revealed loss of habituation to repetitive startles, increased oxidative damage, endoplasmic reticulum (ER) stress, and metabolome abnormalities. The BPA-induced model shows predictive validity, since the approved ALS drug edaravone counteracted BPA-induced motor phenotypes, ER stress, and metabolic disruptions. Overall, BPA exposure is a promising model of ALS-related redox and ER imbalances, contributing to fulfil an unmet need for validated sporadic ALS models.


Asunto(s)
Esclerosis Amiotrófica Lateral , Enfermedades Neurodegenerativas , Animales , Humanos , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Edaravona , Pez Cebra , Oxidación-Reducción
3.
Front Sports Act Living ; 6: 1365717, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38516535

RESUMEN

Background: The association between poor gait and functional movement ability and metabolic syndrome (MetS) has been well established in older adults. A continuous cardiometabolic risk score, MetSindex, may more easily identify individuals at risk for cardiometabolic disease who do not yet meet the stringent criteria for a formal MetS diagnosis. Although the association between MetS and gait velocity is well established in older adults, no such relationship has been identified in younger adults; a group experiencing a rapid increase in the development of MetS. Methods: MetSindex was determined for 21 young adults using standard procedures. Gait velocity was measured as participants completed a ten-meter walk test. Spatiotemporal parameters of gait were also derived using a motion capture system. Simple linear regression was used to determine the relationship between MetSindex and gait velocity, as well as MetSindex and spatiotemporal parameters of gait. Results: There was a large inverse relationship between MetSindex and gait velocity. A large inverse relationship was also observed between MetSindex and cadence, and a large positive relationship was observed between stance time and double limb support time. Conclusions: Gait velocity slows in young adults who do not necessarily meet the criterion for positive diagnosis of MetS-but demonstrate an increased risk for MetS and cardiovascular disease through higher MetSindex scores. The mechanism underlying reduced gait velocity may be fewer, but not shorter steps. Determining easy-to-use surrogates of MetS (e.g., gait velocity) may help combat the growing prevalence of MetS by increasing access to preventative approaches.

4.
Cureus ; 16(2): e54070, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38481920

RESUMEN

Background Glaucoma is a progressive optic neuropathy that may result in irreversible visual impairment and can diminish quality of life. Lowering intraocular pressure (IOP) through topical eyedrops is usually the primary approach to managing glaucoma. However, long-term treatment poses a risk to ocular surface health, leading to ocular surface disease (OSD). Preservative-containing eyedrops are implicated in OSD development due to their detrimental effects on the tear film and goblet cell density. OSD symptoms may impact patient compliance due to local side effects. This study aims to assess OSD in glaucoma patients receiving topical treatment, quantify symptoms and objective ocular surface parameters, and compare them to a control group not using topical glaucoma medications. Methodology Patients diagnosed with primary open-angle glaucoma receiving topical treatment and a control group were included in this study. To assess OSD, patients completed the Ocular Surface Disease Index (OSDI) questionnaire to evaluate symptoms and underwent objective measurements of ocular surface parameters using a keratograph. These parameters included assessments of bulbar redness and non-invasive keratograph tear break-up time (NIKTBUT). Results A cohort of 92 patients was subjected to examination, comprising 66 individuals diagnosed with glaucoma and 26 controls. Within the glaucoma patient subset, the mean number of IOP-lowering drugs administered was 2.42 ± 0.18, with 22.7% exclusively utilizing preservative-free eye drops. Our investigations unveiled a substantial prevalence of OSD symptoms, manifesting not only within the glaucoma cohort but also among the control group, with 72.7% and 53.8%, respectively (p = 0.224), reporting moderate-to-severe symptoms (OSDI > 23). Remarkably, OSDI scores exhibited higher values among female participants (p = 0.039) and glaucoma patients using prostaglandins (p<0.001) and were negatively correlated to the number of IOP-lowering drugs used (-0.448; p < 0.001). Furthermore, employing keratograph assessment, we discerned heightened bulbar redness (1.86 ± 0.07) in the glaucoma group compared to the control group (1.58 ± 0.07; p = 0.008). Glaucoma subgroup analyses further unveiled higher bulbar redness among glaucoma patients employing carbonic anhydrase inhibitors (p = 0.035) and applying medication preservatives (p = 0.045) but lower among individuals using beta-blockers (p = 0.018). However, the NIKTBUT did not show significant variance between the two groups (glaucoma group: 10.19 ± 0.85 seconds; control group: 10.96 ± 1.37 seconds; p = 0.499). Conclusions Our study revealed a significant prevalence of OSD in our sample, with the OSDI questionnaire showing limited specificity. The notable increase in bulbar redness pointed to an elevated prevalence of OSD among glaucoma patients, emphasizing the considerable impact of preservatives on ocular surface damage. Recognizing the potential damage to the tear film and ocular surface is crucial for glaucoma experts, who must employ comprehensive therapeutic strategies to mitigate symptoms, advocating for the preferential use of preservative-free medications, when possible, for optimizing long-term treatment.

5.
BMC Ophthalmol ; 24(1): 123, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38494487

RESUMEN

INTRODUCTION: In neovascular age-related macular degeneration (nAMD) trials, anti-VEGF injection frequency decreases after the first year, while outcomes remain primarily related to the number of injections. To the best of our knowledge, there are no reports of maintaining the best corrected visual acuity (BCVA) for more than 7 years in extension studies. OBJECTIVE: To report a 12-year follow-up of a real-world case of nAMD where BCVA was preserved from declining. CASE DESCRIPTION: A 67-year-old Caucasian female presented to our department in June 2010 due to decreased vision in her left eye (LE) within the preceding months. Examination showed a BCVA of 85 letters (L) in the right eye (RE) and 35 L in the LE. Fundus examination showed drusen in the macula of both eyes. Macular edema, loss of the macular lutein pigment, macular hypo/hyperpigmentation were observed in the LE. A diagnosis of Type 2 choroidal neovascular membrane (CNV) in the LE was established and within two months a Type 1 CNV developed in the RE. She undergone 9 injections of bevacizumab (six) and ranibizumab (three) within the first year of treatment in the LE and seven injections of ranibizumab within the first year in the RE. RESULTS: The LE had a mean of 5.2 injections per year, and the RE had a mean of 7.5 injections per year, from 2010 to 2022. RE's BCVA dropped by 8L (85L to 77L) and central retinal thickness (CRT) increased by 16 µm (276 µm to 292 µm) while LE's BCVA increased by 28L (35L to 63L) and CRT decreased by 369 µm (680 µm to 311 µm), at the twelfth year. CONCLUSIONS: Although the final visual outcome depends on baseline BCVA and lesion type or size, the number of injections is paramount in preserving BCVA and achieving favorable functional outcomes in nAMD, even after 12 years of treatment.


Asunto(s)
Neovascularización Coroidal , Edema Macular , Humanos , Femenino , Anciano , Ranibizumab/uso terapéutico , Inhibidores de la Angiogénesis/uso terapéutico , Factor A de Crecimiento Endotelial Vascular , Inyecciones Intravítreas , Edema Macular/tratamiento farmacológico , Neovascularización Coroidal/diagnóstico , Neovascularización Coroidal/tratamiento farmacológico , Agudeza Visual
6.
Cureus ; 16(1): e52734, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38384633

RESUMEN

Alexia is an acquired reading disorder known as pure alexia or alexia without agraphia when unaccompanied by other higher-level deficits. We present the case of a 40-year-old man experiencing a sudden-onset headache and blurred vision. Despite an absence of known medical history, the patient exhibited a distinctive difficulty in reading without impairing other language aspects accompanied by a right superior homonymous quadrantanopia. Through comprehensive ophthalmological and neurological evaluations, a diagnosis of pure alexia was established. An imaging scan uncovered a left posterior cerebral artery occlusion as the underlying cause. Meticulous assessments of visual acuity, perimetry, and non-visual functions played a pivotal role in decisively diagnosing this condition. This case emphasizes the indispensable role of ophthalmologists in recognizing urgent clinical conditions that extend beyond ophthalmic concerns.

7.
Cureus ; 16(1): e52826, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38406050

RESUMEN

Hypertensive anterior uveitis poses diagnostic challenges owing to its multiple potential etiologies. Cytomegalovirus (CMV) infection is an under-recognized cause that exhibits diverse clinical presentations. This case report focuses on the intricate diagnostic challenge encountered in a 66-year-old immunocompetent patient with CMV-induced hypertensive anterior uveitis. The patient's history, encompassing angle closure glaucoma and topiramate use, contributed to the hypertensive crisis. Initial management included intraocular pressure (IOP)-lowering medication, topiramate discontinuation, and bilateral phacoemulsification, successfully normalizing IOP. However, a subsequent recurrence prompted a detailed investigation. The identification of keratic precipitates and a synechial closed angle led to aqueous humor sampling and polymerase chain reaction (PCR) testing, unveiling the presence of CMV-DNA. Treatment led to a favorable response, resolving ocular inflammation and effectively controlling IOP. This case underscores the complexity of diagnosing and managing CMV-induced hypertensive anterior uveitis, emphasizing the critical role of a comprehensive approach in achieving successful outcomes.

8.
Int J Mol Sci ; 25(2)2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38279246

RESUMEN

Modifications in DNA repair pathways are recognized as prognostic markers and potential therapeutic targets in various cancers, including non-small cell lung cancer (NSCLC). Overexpression of ERCC1 correlates with poorer prognosis and response to platinum-based chemotherapy. As a result, there is a pressing need to discover new inhibitors of the ERCC1-XPF complex that can potentiate the efficacy of cisplatin in NSCLC. In this study, we developed a structure-based virtual screening strategy targeting the inhibition of ERCC1 and XPF interaction. Analysis of crystal structures and a library of small molecules known to act against the complex highlighted the pivotal role of Phe293 (ERCC1) in maintaining complex stability. This residue was chosen as the primary binding site for virtual screening. Using an optimized docking protocol, we screened compounds from various databases, ultimately identifying more than one hundred potential inhibitors. Their capability to amplify cisplatin-induced cytotoxicity was assessed in NSCLC H1299 cells, which exhibited the highest ERCC1 expression of all the cell lines tested. Of these, 22 compounds emerged as promising enhancers of cisplatin efficacy. Our results underscore the value of pinpointing crucial molecular characteristics in the pursuit of novel modulators of the ERCC1-XPF interaction, which could be combined with cisplatin to treat NSCLC more effectively.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Cisplatino/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Reparación del ADN , Proyectos de Investigación , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Proteínas de Unión al ADN/metabolismo , Endonucleasas/metabolismo
9.
Artículo en Inglés | MEDLINE | ID: mdl-37937567

RESUMEN

INTRODUCTION: When it comes to disease modeling, countless models are available for Lysosomal Storage Diseases (LSD). Historically, two major approaches are well-established: in vitro assessments are performed in patient fibroblasts, while in vivo pre-clinical studies are performed in mouse models. Still, both platforms have a series of drawbacks. Thus, we implemented two alternative and innovative protocols to mimic a particular sub-group of LSDs, the Mucopolysaccharidoses both in vitro and in vivo. METHODS: The first one relies on a non-invasive approach using dental pulp stem cells from deciduous teeth (SHEDs). SHEDs are multipotent neuronal precursors that can easily be collected. The second uses a state-of-the-art gene editing technology (CRISPR/Cas9) to generate zebrafish disease models. RESULTS: Even though this is an ongoing project, we have already established and characterized two MPS II and one MPS VI SHED cell models. These cells self-maintain through several passages and can give rise to a variety of cells including neurons. Furthermore, all MPS-associated sub-cellular phenotypes we have assessed so far are easily observable in these cells. Regarding our zebrafish models, we have successfully knocked down both naglu and hgsnat and the first results we got from the behavioral analysis are promising ones, as we can observe altered activity and sleep patterns in the genetically modified fish. For this particular approach we chose MPS III forms as our target disorders, since their neurological features (hyperactivity, seizures and motor impairment) and lifespan decrease would be easily recognizable in zebrafish. CONCLUSION: Now that these methods are well-established in our lab, their potential is immense. On one hand, the newly developed models will be of ultimate value to understand the mechanisms underlying MPS sub-cellular pathology, which have to be further elucidated. On the other hand, they will constitute an optimal platform for drug testing in house. Also noteworthy, our models will be published as lab resources and made available for the whole LSD community.

10.
Nat Commun ; 14(1): 5584, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37696800

RESUMEN

Spatial heterogeneity in antibiotic concentrations is thought to accelerate the evolution of antibiotic resistance, but current theory and experiments have overlooked the effect of cell motility on bacterial adaptation. Here, we study bacterial evolution in antibiotic landscapes with a quantitative model where bacteria evolve under the stochastic processes of proliferation, death, mutation and migration. Numerical and analytical results show that cell motility can both accelerate and decelerate bacterial adaptation by affecting the degree of genotypic mixing and ecological competition. Moreover, we find that for sufficiently high rates, cell motility can limit bacterial survival, and we derive conditions for all these regimes. Similar patterns are observed in more complex scenarios, namely where bacteria can bias their motion in chemical gradients (chemotaxis) or switch between motility phenotypes either stochastically or in a density-dependent manner. Overall, our work reveals limits to bacterial adaptation in antibiotic landscapes that are set by cell motility.


Asunto(s)
Aclimatación , Antibacterianos , Antibacterianos/farmacología , Bacterias/genética , Quimiotaxis , Farmacorresistencia Microbiana/genética
11.
EFORT Open Rev ; 8(8): 626-638, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37526242

RESUMEN

The total number of spine surgeries is increasing, with a variable percentage of patients remaining symptomatic and functionally impaired after surgery. Rehabilitation has been widely recommended, although its effects remain unclear due to lack of research on this matter. The aim of this comprehensive review is to resume the most recent evidence regarding postoperative rehabilitation after spine surgery and make recommendations. The effectiveness of cervical spine surgery on the outcomes is moderate to good, so most physiatrists and surgeons agree that patients benefit from a structured postoperative rehabilitation protocol and despite best timing to start rehabilitation is still unknown, most programs start 4-6 weeks after surgery. Lumbar disc surgery has shown success rates between 78% and 95% after 2 years of follow-up. Postoperative rehabilitation is widely recommended, although its absolute indication has not yet been proven. Patients should be educated to start their own postoperative rehabilitation immediately after surgery until they enroll on a rehabilitation program usually 4-6 weeks post-intervention. The rate of lumbar interbody fusion surgery is increasing, particularly in patients over 60 years, although studies report that 25-45% of patients remain symptomatic. Despite no standardized rehabilitation program has been defined, patients benefit from a cognitive-behavioral physical therapy starting immediately after surgery with psychological intervention, patient education and gradual mobilization. Formal spine rehabilitation should begin at 2-3 months postoperatively. Rehabilitation has benefits on the recovery of patients after spine surgery, but further investigation is needed to achieve a standardized rehabilitation approach.

12.
Cancers (Basel) ; 15(15)2023 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-37568630

RESUMEN

Manganese(III) porphyrin MnTnBuOE-2-PyP5+ (MnBuOE, BMX-001) is a third-generation redox-active cationic substituted pyridylporphyrin-based drug with a good safety/toxicity profile that has been studied in several types of cancer. It is currently in four phase I/II clinical trials on patients suffering from glioma, head and neck cancer, anal squamous cell carcinoma and multiple brain metastases. There is yet an insufficient understanding of the impact of MnBuOE on lung cancer. Therefore, this study aims to fill this gap by demonstrating the effects of MnBuOE on non-small cell lung cancer (NSCLC) A549 and H1975 cell lines. The cytotoxicity of MnBuOE alone or combined with cisplatin was evaluated by crystal violet (CV) and/or 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-Tetrazolium (MTS) reduction assays. Intracellular ROS levels were assessed using two fluorescent probes. Furthermore, the impact of MnBuOE alone or in combination with cisplatin on collective cell migration, individual chemotactic migration and chemoinvasion was assessed using the wound-healing and transwell assays. The expression of genes related to migration and invasion was assessed through RT-qPCR. While MnBuOE alone decreased H1975 cell viability at high concentrations, when combined with cisplatin it markedly reduced the viability of the more invasive H1975 cell line but not of A549 cell line. However, MnBuOE alone significantly decreased the migration of both cell lines. The anti-migratory effect was more pronounced when MnBuOE was combined with cisplatin. Finally, MnBuOE alone or combined with cisplatin significantly reduced cell invasion. MnBuOE alone or combined with cisplatin downregulated MMP2, MMP9, VIM, EGFR and VEGFA and upregulated CDH1 in both cell lines. Overall, our data demonstrate the anti-metastatic potential of MnBuOE for the treatment of NSCLC.

13.
J Med Chem ; 66(20): 14080-14094, 2023 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-37616241

RESUMEN

The search for more effective and selective drugs to overcome cancer multidrug resistance is urgent. As such, a new series of ruthenium-cyclopentadienyl ("RuCp") compounds with the general formula [Ru(η5-C5H4R)(4,4'-R'-2,2'-bipy)(PPh3)] were prepared and fully characterized. All compounds were evaluated toward non-small cell lung cancer cells with different degrees of cisplatin sensitivity (A549, NCI-H2228, Calu-3, and NCI-H1975), showing better cytotoxicity than the first-line chemotherapeutic drug cisplatin. Compounds 2 and 3 (R' = -OCH3; R = CHO (2) or CH2OH (3)) further inhibited the activity of P-gp and MRP1 efflux pumps by impairing their catalytic activity. Molecular docking calculations identified the R-site P-gp pocket as the preferred one, which was further validated using site-directed mutagenesis experiments in P-gp. Altogether, our results unveil the first direct evidence of the interaction between P-gp and "RuCp" compounds in the modulation of P-gp activity and establish them as valuable candidates to circumvent cancer MDR.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Rutenio , Humanos , Antineoplásicos/farmacología , Rutenio/farmacología , Cisplatino/farmacología , Simulación del Acoplamiento Molecular , Compuestos de Rutenio/farmacología , Línea Celular Tumoral , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos
14.
Toxins (Basel) ; 15(7)2023 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-37505680

RESUMEN

Protonation of key histidine residues has been long implicated in the acid-mediated cellular action of the diphtheria toxin translocation (T-) domain, responsible for the delivery of the catalytic domain into the cell. Here, we use a combination of computational (constant-pH Molecular Dynamics simulations) and experimental (NMR, circular dichroism, and fluorescence spectroscopy along with the X-ray crystallography) approaches to characterize the initial stages of conformational change happening in solution in the wild-type T-domain and in the H223Q/H257Q double mutant. This replacement suppresses the acid-induced transition, resulting in the retention of a more stable protein structure in solutions at pH 5.5 and, consequently, in reduced membrane-disrupting activity. Here, for the first time, we report the pKa values of the histidine residues of the T-domain, measured by NMR-monitored pH titrations. Most peaks in the histidine side chain spectral region are titrated with pKas ranging from 6.2 to 6.8. However, the two most up-field peaks display little change down to pH 6, which is a limiting pH for this protein in solution at concentrations required for NMR. These peaks are absent in the double mutant, suggesting they belong to H223 and H257. The constant-pH simulations indicate that for the T-domain in solution, the pKa values for histidine residues range from 3.0 to 6.5, with those most difficult to protonate being H251 and H257. Taken together, our experimental and computational data demonstrate that previously suggested cooperative protonation of all six histidines in the T-domain does not occur.


Asunto(s)
Toxina Diftérica , Histidina , Toxina Diftérica/química , Histidina/química , Simulación de Dinámica Molecular , Dominio Catalítico , Transporte de Proteínas , Concentración de Iones de Hidrógeno , Conformación Proteica
15.
Materials (Basel) ; 16(13)2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37445134

RESUMEN

The design of continuous thickeners and clarifiers is commonly based on the solid flux theory. Batch sedimentation experiments conducted with solid concentrations still provide useful information for their application. The construction of models for the velocity of settling allows the estimation of the flux of solids throughout time, which can, in turn, be used to find the area of the units required to achieve a given solid concentration in the clarified stream. This paper addresses the numerical treatment of data obtained from batch sedimentation experiments of calcium carbonate particles. We propose a systematic framework to fit a model that is capable of representing the process features that involve (i) the numerical differentiation of data to generate initial estimates for the instantaneous velocity of settling; (ii) the integration of a differential equation to fit the model for the velocity of settling; and (iii) the assessment of the quality of the fit using common statistical indicators. The model used for demonstration has a theoretical basis combined with an empirical component to account for the effect of the particle concentrations and their state of aggregation. The values of the numerical parameters obtained are related to the characteristic dimensions of the aggregates and their mass-length fractal dimensions.

16.
Molecules ; 28(11)2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37298742

RESUMEN

(S)-Norcoclaurine is synthesized in vivo through a metabolic pathway that ends with (S)-norcoclaurine synthase (NCS). The former constitutes the scaffold for the biosynthesis of all benzylisoquinoline alkaloids (BIAs), including many drugs such as the opiates morphine and codeine and the semi-synthetic opioids oxycodone, hydrocodone, and hydromorphone. Unfortunately, the only source of complex BIAs is the opium poppy, leaving the drug supply dependent on poppy crops. Therefore, the bioproduction of (S)-norcoclaurine in heterologous hosts, such as bacteria or yeast, is an intense area of research nowadays. The efficiency of (S)-norcoclaurine biosynthesis is strongly dependent on the catalytic efficiency of NCS. Therefore, we identified vital NCS rate-enhancing mutations through the rational transition-state macrodipole stabilization method at the Quantum Mechanics/Molecular Mechanics (QM/MM) level. The results are a step forward for obtaining NCS variants able to biosynthesize (S)-norcoclaurine on a large scale.


Asunto(s)
Alcaloides , Bencilisoquinolinas , Ligasas de Carbono-Nitrógeno , Papaver , Alcaloides/metabolismo , Ligasas de Carbono-Nitrógeno/genética , Ligasas de Carbono-Nitrógeno/metabolismo , Codeína , Papaver/genética , Papaver/metabolismo
17.
J Chem Inf Model ; 63(14): 4447-4457, 2023 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-37132512

RESUMEN

Protein aggregation is a complex process, strongly dependent on environmental conditions and highly structurally heterogeneous, both at the final level of fibril structure and intermediate level of oligomerization. Since the first step in aggregation is the formation of a dimer, it is important to clarify how certain properties of the latter (e.g., stability or interface geometry) may play a role in self-association. Here, we report a simple model that represents the dimer's interfacial region by two angles and combine it with a simple computational method to investigate how modulations of the interfacial region occurring on the ns-µs time scale change the dimer's growth mode. To illustrate the proposed methodology, we consider 15 different dimer configurations of the ß2m D76N mutant protein equilibrated with long Molecular Dynamics simulations and identify which interfaces lead to limited and unlimited growth modes, having, therefore, different aggregation profiles. We found that despite the highly dynamic nature of the starting configurations, most polymeric growth modes tend to be conserved within the studied time scale. The proposed methodology performs remarkably well taking into consideration the nonspherical morphology of the ß2m dimers, which exhibit unstructured termini detached from the protein's core, and the relatively weak binding affinities of their interfaces, which are stabilized by nonspecific apolar interactions. The proposed methodology is general and can be applied to any protein for which a dimer structure has been experimentally determined or computationally predicted.


Asunto(s)
Simulación de Dinámica Molecular , Agregado de Proteínas , Amiloide/química
18.
Eur J Appl Physiol ; 123(10): 2157-2165, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37221340

RESUMEN

PURPOSE: Exercise is a critical element for the management of body weight and improvement of quality of life of individuals with obesity. Due to its convenience and accessibility, running is a commonly used exercise modality to meet exercise guidelines. However, the weight-bearing component during high impacts of this exercise modality might limit the participation in exercise and reduce the effectiveness of running-based exercise interventions in individuals with obesity. The hip flexion feedback system (HFFS) assists participants in meeting specific exercise intensities by giving the participant specific increased hip flexion targets while walking on a treadmill. The resulting activity involves walking with increased hip flexion which removes the high impacts of running. The purpose of this study was to compare physiological and biomechanical parameters during an HFFS session and an independent treadmill walking/running session (IND). METHODS: Heart rate, oxygen consumption (VO2), heart rate error, and tibia peak positive accelerations (PPA) were investigated for each condition at 40% and 60% of heart rate reserve exercise intensities. RESULTS: VO2 was higher for IND despite no differences in heart rate. Tibia PPAs were reduced during the HFFS session. Heart rate error was reduced for HFFS during non-steady state exercise. CONCLUSION: While demanding lower energy consumption compared to running, HFFS exercise results in lower tibia PPAs and more accurate monitoring of exercise intensity. HFFS might be a valid exercise alternative for individuals with obesity or individuals that require low-impact forces at the lower limbs.


Asunto(s)
Marcha , Calidad de Vida , Humanos , Marcha/fisiología , Ejercicio Físico/fisiología , Caminata/fisiología , Obesidad/terapia , Prueba de Esfuerzo , Consumo de Oxígeno/fisiología
19.
Microorganisms ; 11(3)2023 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-36985245

RESUMEN

Grapevine is one of the most important fruit crops worldwide, being Portugal one of the top wine producers. It is well established that wine sensory characteristics from a particular region are defined by the physiological responses of the grapevine to its environment and thus, the concept of terroir in viticulture was established. Among all the factors that contribute to terroir definition, soil microorganisms play a major role from nutrient recycling to a drastic influence on plant fitness (growth and protection) and of course wine production. Soil microbiome from four different terroirs in Quinta dos Murças vineyard was analysed through long-read Oxford Nanopore sequencing. We have developed an analytical pipeline that allows the identification of function, ecologies, and indicator species based on long read sequencing data. The Douro vineyard was used as a case study, and we were able to establish microbiome signatures of each terroir.

20.
Neurosci Biobehav Rev ; 148: 105138, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36933816

RESUMEN

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease that leads to progressive disability and motor impairment. Existing therapies provide modest improvements in patient survival, raising a need for new treatments for ALS. Zebrafish is a promising model animal for translational and fundamental research in ALS - it is an experimentally tractable vertebrate, with high homology to humans and an ample experimental toolbox. These advantages allow high-throughput study of behavioral and pathophysiological phenotypes. The last decade saw an increased interest in modelling ALS in zebrafish, leading to the current abundance and variety of available methods and models. Additionally, the rise of gene editing techniques and toxin combination studies has created novel opportunities for ALS studies in zebrafish. In this review, we address the relevance of zebrafish as a model animal for ALS studies, the strategies for model induction and key phenotypical evaluation. Furthermore, we discuss established and emerging zebrafish models of ALS, analyzing their validity, including their potential for drug testing, and highlighting research opportunities in this area.


Asunto(s)
Esclerosis Amiotrófica Lateral , Enfermedades Neurodegenerativas , Animales , Humanos , Pez Cebra/genética , Natación , Modelos Animales de Enfermedad , Superóxido Dismutasa-1/genética , Mutación
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