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1.
Z Gerontol Geriatr ; 2024 Jun 26.
Artículo en Alemán | MEDLINE | ID: mdl-38926201

RESUMEN

BACKGROUND: Geriatric patients after hospitalization often utilize subacute inpatient care (SC); however, little is known about their care and further health status. OBJECTIVE: To identify persons in SC with rehabilitation needs and improvement potential after hospitalization and to describe the care, relevant parameters of the health status as well as use of medical/nursing services in and after SC. METHODS: After positive screening for previous hospitalization and need of rehabilitation with improvement potential in 13 nursing homes, the length of stay, therapeutic treatments and physician contacts in SC as well as functional parameters, pain, quality of life and the utilization of services according to the Social Security Code V (SGB V) and SGB XI were assessed at baseline, at the end and 3 months after SC. RESULTS: A total of 108 (44%) out of 243 screened persons with previous hospitalization had a need of rehabilitation with improvement potential, of whom 57 participated in the study. In SC (median = 26 days) 35% received no therapeutic treatments and 28% had no physician contact. After SC 40% were transferred to rehabilitation. Participants with rehabilitation transition more frequently received therapeutic treatments in SC (p = 0.021) and were less frequently in long-term care 3 months after SC (p = 0.015). CONCLUSION: This study suggests that a high proportion of persons in SC after hospitalization are in need of rehabilitation with improvement potential, which is not sufficiently treated. Regular therapeutic treatments in SC could improve the transition rate to rehabilitation and subsequent home environment.

2.
Trop Anim Health Prod ; 54(1): 72, 2022 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-35064854

RESUMEN

Pastoral and agro-pastoral farming are extensively practised in Ethiopia, and the main livestock kept are cattle, goats, sheep, poultry, and camels. The livestock sector is faced with complex challenges including limited availability of well-trained and skilled animal health professionals. The objective of this study was to identify and prioritise areas for training with the goal of providing evidence to guide strategies to improve the skills, delivery, and governance of veterinary services across Ethiopia. A cross-sectional survey was developed and administered electronically to veterinary professionals in Ethiopia using the Qualtrics platform. Data were collected on select parameters including demographics, diseases of economic significance, diagnosis, disease prevention, biosecurity, disease control, treatment, epidemiology, One Health, disease reporting, and the participants' opinions about training. The survey data was downloaded in Microsoft Excel and descriptive statistics performed. A total of 234 veterinary professionals completed the survey. Most participants were male (89.7%) and aged between 26 and 35 years (81.2%). Of the total respondents, 56.4% worked in government and 8.5% in private practice. Most participants perceived training on laboratory diagnostic testing, disease prevention, antimicrobial resistance, antibiotic sensitivity testing, basic epidemiology, and clinical procedures, as most beneficial. In addition, most respondents would like to receive training on diseases affecting cattle, poultry, and small ruminants. The findings from this study provide baseline information on priority training areas for veterinary professionals and could potentially contribute to national efforts to develop and implement a continuing professional development programme in the veterinary domain, in view of improving veterinary service delivery.


Asunto(s)
Bioaseguramiento , Ganado , Animales , Bovinos , Estudios Transversales , Etiopía/epidemiología , Masculino , Evaluación de Necesidades , Ovinos
3.
J Vet Med Educ ; 49(4): 503-514, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34077337

RESUMEN

In Uganda, delivery of veterinary services is vital to animal health and productivity, and is heavily dependent on well-trained and skilled animal health professionals. The purpose of this study was to identify and prioritize areas for refresher training and continuous professional development of animal health professionals (veterinarians and veterinary paraprofessionals), with the overarching aim of improving veterinary service delivery in Uganda. A survey was administered electronically to 311 animal health professionals during the period November 14-30, 2019. Data were collected on relevant parameters including demographics, knowledge on preventive medicine, diagnostics, disease control and treatment, epidemiology, and One Health, as well as participants' opinions on training priorities, challenges faced, and constraints to veterinary service delivery. Most respondents were veterinarians 26-35 years old, were male, and worked in clinical practice. Lowest perceived knowledge was reported on subjects relating to laboratory diagnostics, antimicrobial resistance (AMR), and nutrition. Training topics considered to be of most benefit to respondents included laboratory diagnostics, treatment of common livestock diseases, AMR, and practical clinical skills in reproductive and preventive medicine. Participants preferred to receive training in the form of practical workshops, in-practice training, and external training. This study highlights the need to prioritize training in practical clinical skills, laboratory diagnostics, and AMR. Wet labs and hands-on practical clinical and laboratory skills should be incorporated to enhance training. Provision of targeted and successful trainings will be dependent on the allocation of adequate resources and support by relevant public and private stakeholders across the veterinary sector.


Asunto(s)
Educación en Veterinaria , Veterinarios , Animales , Educación Continua , Femenino , Humanos , Masculino , Evaluación de Necesidades , Uganda
4.
J Gastroenterol Hepatol ; 36(11): 3033-3040, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34151470

RESUMEN

BACKGROUND AND AIM: One of the most impacted regions by the pandemic globally, Latin America is facing socioeconomic and health-care challenges that can potentially affect disease outcomes. Recent data suggest that inflammatory bowel disease (IBD) patients do not have an increased risk of the development of COVID-19 complications. However, the impact of COVID-19 on IBD patients living in least developed areas remains to be fully elucidated. This study aims to describe the outcomes of IBD patients diagnosed with COVID-19 in countries from Latin America based on data from the SECURE-IBD registry. METHODS: Patients from Latin America enrolled in the SECURE-IBD registry were included. Descriptive analyses were used to summarize clinical and sociodemographic characteristics. The studied outcomes were (i) a composite of need for intensive care unit admission, ventilator use, and/or death (primary outcome) and (ii) a composite of any hospitalization and/or death (secondary outcome). Multivariable regression was used to identify risk factors of severe COVID-19. RESULTS: During the study period, 230 cases (Crohn's disease: n = 115, ulcerative colitis: n = 114, IBD-unclassified [IBD-U]: n = 1) were reported to the SECURE-IBD database from 13 different countries. Primary outcome was observed in 17 (7.4%) patients, and the case fatality rate was 1.7%. In the adjusted multivariable model, the use of systemic corticosteroids (odds ratio [OR] 10.97; 95% confidence interval [CI]: 3.44-34.99) was significantly associated with the primary outcome. Older age (OR 1.03; 95% CI: 1.00-1.05), systemic corticosteroids (OR 9.33; 95% CI: 3.84-22.63), and the concomitant presence of one (OR 2.14; 95% CI: 0.89-5.15) or two (OR 10.67; 95% CI: 1.74-65.72) comorbidities were associated with the outcome of hospitalization or death. CONCLUSION: Inflammatory bowel disease patients with COVID-19 in Latin America appear to have similar outcomes to the overall global data. Risk factors of severe COVID-19 are similar to prior reports.


Asunto(s)
COVID-19/diagnóstico , Colitis Ulcerosa/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/complicaciones , Corticoesteroides/uso terapéutico , Anciano , COVID-19/epidemiología , Colitis Ulcerosa/epidemiología , Enfermedad de Crohn/tratamiento farmacológico , Enfermedad de Crohn/epidemiología , Humanos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/epidemiología , América Latina/epidemiología , Sistema de Registros , SARS-CoV-2
5.
Curr Opin Gastroenterol ; 35(4): 259-264, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30973356

RESUMEN

PURPOSE OF REVIEW: Epidemiological studies of inflammatory bowel disease (IBD) in newly industrialized countries are limited, due to a lack of medical surveillance systems and reliable and unified registries and databases. In Brazil, reliable data on the incidence and prevalence of Crohn's disease and ulcerative colitis is scarce. The objective of the present review is to describe in detail the available data on the incidence and prevalence of Crohn's disease and ulcerative colitis in Brazil. RECENT FINDINGS: The authors identified the single four population-based studies which refer to incidence and prevalence of IBD in the country (two from São Paulo, one from Espírito Santo and one from the state of Piauí). These studies demonstrate a remarkable growth in the incidence and estimated prevalence of IBD in Brazil, with higher number of cases in more developed regions. SUMMARY: The increase in incidence over time and the higher current prevalence are indicative of a historical progression in relation to the number of IBD patients in our country, similar to what was observed in countries from Asia and approximating those of the northern hemisphere. Epidemiological studies with more accurate methodology are needed in Brazil.


Asunto(s)
Colitis Ulcerosa , Enfermedades Inflamatorias del Intestino , Brasil/epidemiología , Colitis Ulcerosa/epidemiología , Humanos , Incidencia , Enfermedades Inflamatorias del Intestino/epidemiología , Internacionalidad , Prevalencia
6.
Proc Natl Acad Sci U S A ; 113(50): 14189-14194, 2016 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-27911829

RESUMEN

The covalent modification of therapeutic biomolecules has been broadly explored, leading to a number of clinically approved modified protein drugs. These modifications are typically intended to address challenges arising in biopharmaceutical practice by promoting improved stability and shelf life of therapeutic proteins in formulation, or modifying pharmacokinetics in the body. Toward these objectives, covalent modification with poly(ethylene glycol) (PEG) has been a common direction. Here, a platform approach to biopharmaceutical modification is described that relies on noncovalent, supramolecular host-guest interactions to endow proteins with prosthetic functionality. Specifically, a series of cucurbit[7]uril (CB[7])-PEG conjugates are shown to substantially increase the stability of three distinct protein drugs in formulation. Leveraging the known and high-affinity interaction between CB[7] and an N-terminal aromatic residue on one specific protein drug, insulin, further results in altering of its pharmacological properties in vivo by extending activity in a manner dependent on molecular weight of the attached PEG chain. Supramolecular modification of therapeutic proteins affords a noncovalent route to modify its properties, improving protein stability and activity as a formulation excipient. Furthermore, this offers a modular approach to append functionality to biopharmaceuticals by noncovalent modification with other molecules or polymers, for applications in formulation or therapy.


Asunto(s)
Composición de Medicamentos/métodos , Diseño de Fármacos , Polietilenglicoles/química , Animales , Biofarmacia/métodos , Hidrocarburos Aromáticos con Puentes/química , Línea Celular , Química Clic , Sistemas de Liberación de Medicamentos , Humanos , Imidazoles/química , Insulina/química , Insulina/farmacocinética , Masculino , Ratones , Ratones Endogámicos C57BL , Modelos Moleculares , Ingeniería de Proteínas , Estabilidad Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacocinética
7.
Proc Natl Acad Sci U S A ; 112(8): 2401-6, 2015 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-25675515

RESUMEN

Since its discovery and isolation, exogenous insulin has dramatically changed the outlook for patients with diabetes. However, even when patients strictly follow an insulin regimen, serious complications can result as patients experience both hyperglycemic and hypoglycemic states. Several chemically or genetically modified insulins have been developed that tune the pharmacokinetics of insulin activity for personalized therapy. Here, we demonstrate a strategy for the chemical modification of insulin intended to promote both long-lasting and glucose-responsive activity through the incorporation of an aliphatic domain to facilitate hydrophobic interactions, as well as a phenylboronic acid for glucose sensing. These synthetic insulin derivatives enable rapid reversal of blood glucose in a diabetic mouse model following glucose challenge, with some derivatives responding to repeated glucose challenges over a 13-h period. The best-performing insulin derivative provides glucose control that is superior to native insulin, with responsiveness to glucose challenge improved over a clinically used long-acting insulin derivative. Moreover, continuous glucose monitoring reveals responsiveness matching that of a healthy pancreas. This synthetic approach to insulin modification could afford both long-term and glucose-mediated insulin activity, thereby reducing the number of administrations and improving the fidelity of glycemic control for insulin therapy. The described work is to our knowledge the first demonstration of a glucose-binding modified insulin molecule with glucose-responsive activity verified in vivo.


Asunto(s)
Ácidos Borónicos/química , Glucosa/farmacología , Insulina/química , Insulina/uso terapéutico , Animales , Diabetes Mellitus Experimental/tratamiento farmacológico , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Insulina/administración & dosificación , Ratones , Estreptozocina
8.
Phys Chem Chem Phys ; 18(34): 23516-27, 2016 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-27491508

RESUMEN

Investigating the adsorption of peptides on inorganic surfaces, on the molecular level, is fundamental for medicinal and analytical applications. Peptides can be potent as linkers between surfaces and living cells in biochips or in implantation medicine. Here, we studied the adsorption process of the positively charged pentapeptide RTHRK, a recently identified binding sequence for surface oxidized silicon, and novel analogues thereof to negatively charged mica surfaces. Homogeneous formation of monolayers in the nano- and low micromolar peptide concentration range was observed. We propose an alternative and efficient method to both quantify binding affinity and follow adhesion behavior. This method makes use of the thermodynamic relationship between surface coverage, measured by atomic force microscopy (AFM), and the concomitant free energy of adhesion. A knowledge-based fit to the autocorrelation of the AFM images was used to correct for a biased surface coverage introduced by the finite lateral resolution of the AFM. Binding affinities and mechanisms were further explored by large scale molecular dynamics (MD) simulations. The combination of well validated MD simulations with topological data from AFM revealed a better understanding of peptide adsorption processes on the atomistic scale. We demonstrate that binding affinity is strongly determined by a peptide's ability to form salt bridges and hydrogen bonds with the surface lattice. Consequently, differences in hydrogen bond formation lead to substantial differences in binding affinity despite conservation of the peptide's overall charge. Further, MD simulations give access to relative changes in binding energy of peptide variations in comparison to a lead compound.

9.
Phys Chem Chem Phys ; 17(2): 918-27, 2015 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-25408431

RESUMEN

Interest in the topic of amyloid formation by peptides and proteins has increased dramatically in recent years, transforming it from a puzzling phenomenon associated with a small number of diseases into a major subject of study in disciplines ranging from material science to biology and medicine. The tendency of numerous (also non-pathogenic) proteins such as insulin to self-assemble into amyloid-like fibrils is well known. While fibrils are usually easily detected, the observation of transient intermediates is a big challenge in general. They are the key and the 'holy grail' for a molecular understanding of mechanisms in this context. Here we show that intermediates, i.e. oligomers, can be detected and their hydrodynamic radius RH as well as their overall conformation and structure can be monitored and the aggregation dynamics as well as structure formation can be detected in time with a suitable combination of experimental techniques. We have observed transient intermediates that resemble large oligomers held together in solution by non-covalent forces. The oligomers appear to convert into building blocks for mature fibrils with largely beta-sheet conformation resembling key players in a mechanism, which is termed 'nucleated conformation conversion' in the literature. Structural transformations of oligomers in time towards dominant beta-sheet conformations have been observed for the first time. The structures can even be observed in liquid phase AFM experiments. With this approach we have successfully shed new light into the aggregation and fibrilization process of insulin being possibly a model system for other amyloid systems.


Asunto(s)
Amiloide/química , Insulina/química , Luz , Espectrometría de Masas , Microscopía , Multimerización de Proteína , Dispersión de Radiación , Animales , Bovinos , Agregado de Proteínas , Estructura Secundaria de Proteína
10.
Phys Chem Chem Phys ; 17(10): 6858-64, 2015 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-25672904

RESUMEN

Charge separation in condensed matter after strong impacts is a general and intriguing phenomenon in nature, which is often identified and described but not necessarily well understood in terms of a quantitative mechanistic picture. Here we show that charge separation naturally occurs if water droplets/clusters or ice particles with embedded charge carriers, e.g., ions, encounter a high energy impact with subsequent dispersion - even if the involved kinetic energy is significantly below the molecular ionization energy. We find that for low charge carrier concentrations (c < 0.01 mol L(-1)) a simple statistical Poisson model describes the charge distribution in the resulting molecular "fragments" or aggregates. At higher concentrations Coulomb interactions between the charge carriers become relevant, which we describe by a Monte Carlo approach. Our models are compared to experimental data for strong (laser) impacts on liquid micro beams and discussed for the charge generation in cluster-impact mass spectrometry on cosmic dust detectors where particle kinetic energies are below the plasma threshold. Taken together, a simple and intuitive but quantitative microscopic model is obtained, which may contribute to the understanding of a larger range of phenomena related to charge generation and separation in nature.


Asunto(s)
Agua/química , Iones/química , Modelos Teóricos , Método de Montecarlo
11.
Nature ; 459(7250): 1098-101, 2009 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-19553992

RESUMEN

Saturn's moon Enceladus emits plumes of water vapour and ice particles from fractures near its south pole, suggesting the possibility of a subsurface ocean. These plume particles are the dominant source of Saturn's E ring. A previous in situ analysis of these particles concluded that the minor organic or siliceous components, identified in many ice grains, could be evidence for interaction between Enceladus' rocky core and liquid water. It was not clear, however, whether the liquid is still present today or whether it has frozen. Here we report the identification of a population of E-ring grains that are rich in sodium salts ( approximately 0.5-2% by mass), which can arise only if the plumes originate from liquid water. The abundance of various salt components in these particles, as well as the inferred basic pH, exhibit a compelling similarity to the predicted composition of a subsurface Enceladus ocean in contact with its rock core. The plume vapour is expected to be free of atomic sodium. Thus, the absence of sodium from optical spectra is in good agreement with our results. In the E ring the upper limit for spectroscopy is insufficiently sensitive to detect the concentrations we found.

12.
Phys Chem Chem Phys ; 16(36): 19365-75, 2014 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-25102451

RESUMEN

Supercritical water and methanol have recently drawn much attention in the field of green chemistry. It is crucial to an understanding of supercritical solvents to know their dynamics and to what extent hydrogen (H) bonds persist in these fluids. Here, we show that with femtosecond infrared (IR) laser pulses water and methanol can be heated to temperatures near and above their critical temperature Tc and their molecular dynamics can be studied via ultrafast photoelectron spectroscopy at liquid jet interfaces with high harmonics radiation. As opposed to previous studies, the main focus here is the comparison between the hydrogen bonded systems of methanol and water and their interpretation by theory. Superheated water initially forms a dense hot phase with spectral features resembling those of monomers in gas phase water. On longer timescales, this phase was found to build hot aggregates, whose size increases as a function of time. In contrast, methanol heated to temperatures near Tc initially forms a broad distribution of aggregate sizes and some gas. These experimental features are also found and analyzed in extended molecular dynamics simulations. Additionally, the simulations enabled us to relate the origin of the different behavior of these two hydrogen-bonded liquids to the nature of the intermolecular potentials. The combined experimental and theoretical approach delivers new insights into both superheated phases and may contribute to understand their different chemical reactivities.


Asunto(s)
Metanol/química , Termodinámica , Agua/química , Enlace de Hidrógeno , Espectroscopía de Fotoelectrones , Espectrofotometría Infrarroja
13.
Acc Chem Res ; 45(1): 120-30, 2012 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-22075058

RESUMEN

Since the pioneering work of Kai Siegbahn, electron spectroscopy for chemical analysis (ESCA) has been developed into an indispensable analytical technique for surface science. The value of this powerful method of photoelectron spectroscopy (PES, also termed photoemission spectroscopy) and Siegbahn's contributions were recognized in the 1981 Nobel Prize in Physics. The need for high vacuum, however, originally prohibited PES of volatile liquids, and only allowed for investigation of low-vapor-pressure molecules attached to a surface (or close to a surface) or liquid films of low volatility. Only with the invention of liquid beams of volatile liquids compatible with high-vacuum conditions was PES from liquid surfaces under vacuum made feasible. Because of the ubiquity of water interfaces in nature, the liquid water-vacuum interface became a most attractive research topic, particularly over the past 10 years. PES studies of these important aqueous interfaces remained significantly challenging because of the need to develop high-pressure PES methods. For decades, ESCA or PES (termed XPS, for X-ray photoelectron spectroscopy, in the case of soft X-ray photons) was restricted to conventional laboratory X-ray sources or beamlines in synchrotron facilities. This approach enabled frequency domain measurements, but with poor time resolution. Indirect access to time-resolved processes in the condensed phase was only achieved if line-widths could be analyzed or if processes could be related to a fast clock, that is, reference processes that are fast enough and are also well understood in the condensed phase. Just recently, the emergence of high harmonic light sources, providing short-wavelength radiation in ultrashort light pulses, added the dimension of time to the classical ESCA or XPS technique and opened the door to (soft) X-ray photoelectron spectroscopy with ultrahigh time resolution. The combination of high harmonic light sources (providing radiation with laserlike beam qualities) and liquid microjet technology recently enabled the first liquid interface PES experiments in the IR/UV-pump and extreme ultraviolet-probe (EUV-probe) configuration. In this Account, we highlight features of the technology and a number of recent applications, including extreme states of matter and the discovery and detection of short-lived transients of the solvated electron in water. Properties of the EUV radiation, such as its controllable polarization and features of the liquid microjet, will enable unique experiments in the near future. PES measures electron binding energies and angular distributions of photoelectrons, which comprise unique information about electron orbitals and their involvement in chemical bonding. One of the future goals is to use this information to trace molecular orbitals, over time, in chemical reactions or biological transformations.


Asunto(s)
Espectroscopía de Fotoelectrones/instrumentación , Espectroscopía de Fotoelectrones/métodos , Agua/química , Enlace de Hidrógeno , Factores de Tiempo , Vacio
14.
Nature ; 485(7397): E1-2; discussion E2-3, 2012 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-22575967
15.
Vet Parasitol Reg Stud Reports ; 42: 100889, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37321794

RESUMEN

Gastrointestinal parasites are among the most economically important pathogens of small ruminants causing serious economic losses and animal welfare problems for the livestock industry worldwide. The emergence of anthelmintic resistant H. contortus in small ruminants is a serious problem because it undermines effective helminth control and results in reduced productivity. Little is known about resistance to benzimidazoles (BZ) in Haemonchus in goats and sheep in Uganda. The objective of this study was to determine the prevalence of gastrointestinal parasites and to identify the presence of benzimidazole resistance associated mutations in the ß-tubulin isotype 1 gene of Haemonchus contortus in goats from selected districts of Uganda. A total of 200 goats from 10 districts of Uganda slaughtered at Kalerwe abattoir in Kampala were sampled for H. contortus adult worms. Faecal samples were also collected to detect other intestinal parasites. Faecal microscopy and analysis were performed using flotation and sedimentation techniques. DNA was extracted from adult worms and PCR and sequencing of the ITS- 2 region and ß-tubulin isotype 1 gene performed to identify H. contortus species and to determine the presence of mutations associated with anthelmintic resistance respectively. Faecal microscopy showed that the most prevalent intestinal parasites were coccidia (98%), strongyles (97.5%), Strongyloides (82%), Paramphistomum (74.5%), Moniezia (46%), Fasciola (1.5%) and Trichuris (1%). Most goats had a high intestinal burden of coccidia (≥ 5000 oocyst per gram) and strongyles (≥ 1000 egg per gram), 65% and 67.5%, respectively. The prevalence of H. contortus adult worms was 63% (126/200). Sequencing of the partial ß-tubulin isotype 1 gene of 54 Haemonchus contortus adult male isolates revealed the presence of mutations associated with anthelmintic resistance. The F200Y mutation was the most common mutation (13% of samples with good beta-tubulin sequences) followed by the E198A and E198K mutations, both found in 9% of sequenced samples. Mutation F167Y was not identified in any of the samples and there were no heterozygous individuals for any of the SNPS associated with BZ resistance that were identified in this study. These findings highlight the need for controlled use of anthelmintics especially benzimidazoles, to enable sustainable control of H. contortus in Uganda, and a need for further investigation to understand the resistance of other parasites identified in this study.


Asunto(s)
Antihelmínticos , Haemonchus , Parásitos , Masculino , Ovinos , Animales , Haemonchus/genética , Tubulina (Proteína)/genética , Cabras , Prevalencia , Uganda/epidemiología , Bencimidazoles/farmacología , Antihelmínticos/farmacología , Mutación
16.
Cell Rep ; 42(6): 112541, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37243591

RESUMEN

Presynaptic plasticity adjusts neurotransmitter (NT) liberation. Short-term facilitation (STF) tunes synapses to millisecond repetitive activation, while presynaptic homeostatic potentiation (PHP) of NT release stabilizes transmission over minutes. Despite different timescales of STF and PHP, our analysis of Drosophila neuromuscular junctions reveals functional overlap and shared molecular dependence on the release-site protein Unc13A. Mutating Unc13A's calmodulin binding domain (CaM-domain) increases baseline transmission while blocking STF and PHP. Mathematical modeling suggests that Ca2+/calmodulin/Unc13A interaction plastically stabilizes vesicle priming at release sites and that CaM-domain mutation causes constitutive stabilization, thereby blocking plasticity. Labeling the functionally essential Unc13A MUN domain reveals higher STED microscopy signals closer to release sites following CaM-domain mutation. Acute phorbol ester treatment similarly enhances NT release and blocks STF/PHP in synapses expressing wild-type Unc13A, while CaM-domain mutation occludes this, indicating common downstream effects. Thus, Unc13A regulatory domains integrate signals across timescales to switch release-site participation for synaptic plasticity.


Asunto(s)
Proteínas de Drosophila , Animales , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Calmodulina/metabolismo , Terminales Presinápticos/metabolismo , Drosophila/metabolismo , Transmisión Sináptica/fisiología , Sinapsis/metabolismo , Plasticidad Neuronal
17.
Phys Chem Chem Phys ; 14(1): 22-34, 2012 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-22075842

RESUMEN

The hydrated electron is one of the simplest chemical transients and has been the subject of intense investigation and speculation since its discovery in 1962 by Hart and Boag. Although extensive kinetic and spectroscopic research on this species has been reported for many decades, its structure, i.e., the dominant electron-water binding motif, and its binding energy remained uncertain. A recent milestone in the research on the hydrated electron was the determination of its binding energy by liquid-jet photoelectron spectroscopy. It turned out that the assumption of a single electron binding motif in liquid water is an oversimplification. In addition to different isomers in cluster spectroscopy and different transient species of unknown structure in ultrafast experiments, long-lived hydrated electrons near the surface of liquid water have recently been discovered. The present article gives an account of recent work on the topic "solvated electrons" from the perspectives of cluster spectroscopy, condensed-phase spectroscopy, as well as theory. It highlights and critically discusses recent findings and their implications for our understanding of electron solvation in aqueous environments.


Asunto(s)
Electrones , Solventes/química , Agua/química , Cinética , Modelos Químicos , Espectroscopía de Fotoelectrones , Propiedades de Superficie , Termodinámica
18.
Cells ; 11(10)2022 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-35626748

RESUMEN

Colonic epithelial cells are responsible for maintaining a delicate balance between luminal secretion and the absorption of fluids and ions. This review aims to discuss and update the model of colonic electrolyte secretion and absorption via the cystic fibrosis transmembrane regulator (CFTR), epithelial sodium channel (ENaC), Na-K-Cl cotransporters (NKCC1 and 2), Na-H exchangers (NHE1-4), colonic H,KATPase, and several other key components involved in multi-level transepithelial ion transport. Developments in our understanding of the activity, regulation, localization, and relationships of these ion transporters and their interactions have helped forge a more robust understanding of colonic ion movement that accounts for the colonic epithelium's role in mucosal pH modulation, the setting of osmotic gradients pivotal for fluid retention and secretion, and cell death regulation. Deviations from homeostatic ion transport cause diarrhea, constipation, and epithelial cell death and contribute to cystic fibrosis, irritable bowel syndrome (IBS), ulcerative colitis, and cancer pathologies. Signal transduction pathways that regulate electrolyte movement and the regulatory relationships between various sensors and transporters (CFTR as a target of CaSR regulation and as a regulator of ENaC and DRA, for example) are imperative aspects of a dynamic and comprehensive model of colonic ion homeostasis.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística , Fibrosis Quística , Colon/metabolismo , Fibrosis Quística/metabolismo , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Electrólitos/metabolismo , Canales Epiteliales de Sodio/metabolismo , Humanos , Proteínas de Transporte de Membrana/metabolismo
19.
Front Vet Sci ; 9: 898485, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35873688

RESUMEN

Peste des petits ruminants (PPR) is a major constraint to the productivity of small ruminants in Nigeria. Understanding of the current epidemiological status of PPR is crucial to its effective control. A review of the epidemiology of PPR in Nigeria was performed and research gaps were identified. Thirty-seven eligible articles were reviewed: these presented information from 30 of the 36 states of Nigeria. Most studies focused on goats and/or sheep (n = 33) but camels (n = 4), cattle (n = 1) and wild ruminants (n = 2) were also considered. Fourteen (37.8%) of the articles reported seroprevalence in small ruminants, which varied from 0.0% to 77.5% where more than 10 animals were sampled. Molecular characterization and phylogenetic analysis were performed in 6 studies, with lineages II and IV, detected in sheep and goats. In one study in small ruminants, sequences clustering into lineage I showed a similarity to the vaccine strain, Nigeria 75/1, based on phylogenetic analysis of F gene sequences. However, if the preferred method of sequencing the N gene had been performed, this isolate would have been grouped into lineage II. According to N gene phylogenetic analysis in the other studies, sequences were identified that clustered with clade II-NigA, II-NigB (closely related to the Nigeria 75/1 vaccine strain), and others which were well separated, suggesting a high diversity of PPRV in Nigeria. Five articles reported the detection of lineage IV in 22/36 states, with IV-NigA and IV-NigB detected, highlighting its widespread distribution in Nigeria. Risk factors for PPRV seropositivity were reported in 10/37 (27.0%) articles, with a higher seroprevalence observed in female animals, although differing results were observed when considering species and age separately. There were inconsistencies in study design and data reporting between studies which precluded conduct of a meta-analysis. Nevertheless, several research gaps were identified including the need to investigate the low uptake of PPRV vaccine, and the economic benefits of PPR control measures to small ruminant farmers. Such data will inform PPR control strategies in Nigeria and subsequently contribute to the global 2030 PPR eradication strategy.

20.
Sci Rep ; 12(1): 1550, 2022 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-35091568

RESUMEN

An LTR-based quantitative PCR (qPCR) assay was modified and optimized for the quantification of total HIV-1 nucleic acids in plasma and PBMC. TaqMan qPCR primers and probes were designed against the NCBI/LANL HIV-1 compendium database by analyzing sequences used in assays for sensitive cross-clade detection of HIV-1 as reported in the literature and elucidating regions of improved cross-subtype specificity. Inosine and mixed nucleotide bases were included at polymorphic sites. Real-time RT-qPCR and qPCR were performed on plasma viral RNA and cellular lysates. A step-up amplification approach to allow binding of primers across polymorphic regions showed improved sensitivity compared to universal cycling. Unlike a lead competing laboratory-developed assay, all major HIV-1 subtypes, and a wide range of recombinants from a 127-member diversity panel were detected and accurately quantified in spiked plasmas. Semi-nested PCR increased detection sensitivity even further. The assay was able to detect down to 88 copies/mL of HIV-1 in plasma with 95% efficiency or the equivalent of a single infected cell. The PCR assay will be valuable in studies that monitor very low viral levels including residual or break through HIV-1 in patients receiving antiretroviral therapy, in HIV-1 cure, and in other research studies.


Asunto(s)
Leucocitos Mononucleares
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