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1.
Proc Natl Acad Sci U S A ; 119(26): e2202912119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35727967

RESUMO

VEGF was initially discovered due to its angiogenic activity and therefore named "vascular endothelial growth factor." However, its more recently discovered neurotrophic activity may be evolutionarily more ancient. Our previous work showed that all the changes produced by axotomy on the firing activity and synaptic inputs of abducens motoneurons were completely restored after VEGF administration. Therefore, we hypothesized that the lack of VEGF delivered by retrograde transport from the periphery should also affect the physiology of otherwise intact abducens motoneurons. For VEGF retrograde blockade, we chronically applied a neutralizing VEGF antibody to the lateral rectus muscle. Recordings of extracellular single-unit activity and eye movements were made in alert cats before and after the application of the neutralizing antibody. Our data revealed that intact, noninjured abducens motoneurons retrogradely deprived of VEGF exhibited noticeable changes in their firing pattern. There is a general decrease in firing rate and a significant reduction in eye position and eye velocity sensitivity (i.e., a decrease in the tonic and phasic components of their discharge, respectively). Moreover, by means of confocal immunocytochemistry, motoneurons under VEGF blockade showed a marked reduction in the density of afferent synaptic terminals contacting with their cell bodies. Altogether, the present findings demonstrate that the lack of retrogradely delivered VEGF renders abducens motoneurons into an axotomy-like state. This indicates that VEGF is an essential retrograde factor for motoneuronal synaptic drive and discharge activity.


Assuntos
Movimentos Oculares , Neurônios Motores , Terminações Pré-Sinápticas , Fator A de Crescimento do Endotélio Vascular , Animais , Anticorpos Neutralizantes , Axotomia , Gatos , Movimentos Oculares/efeitos dos fármacos , Movimentos Oculares/fisiologia , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/fisiologia , Músculos Oculomotores/efeitos dos fármacos , Músculos Oculomotores/fisiologia , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/fisiologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/farmacologia , Fator A de Crescimento do Endotélio Vascular/fisiologia
2.
Exp Physiol ; 109(1): 17-26, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-36869596

RESUMO

Proprioception is the sense that lets us perceive the location, movement and action of the body parts. The proprioceptive apparatus includes specialized sense organs (proprioceptors) which are embedded in the skeletal muscles. The eyeballs are moved by six pairs of eye muscles and binocular vision depends on fine-tuned coordination of the optical axes of both eyes. Although experimental studies indicate that the brain has access to eye position information, both classical proprioceptors (muscle spindles and Golgi tendon organ) are absent in the extraocular muscles of most mammalian species. This paradox of monitoring extraocular muscle activity in the absence of typical proprioceptors seemed to be resolved when a particular nerve specialization (the palisade ending) was detected in the extraocular muscles of mammals. In fact, for decades there was consensus that palisade endings were sensory structures that provide eye position information. The sensory function was called into question when recent studies revealed the molecular phenotype and the origin of palisade endings. Today we are faced with the fact that palisade endings exhibit sensory as well as motor features. This review aims to evaluate the literature on extraocular muscle proprioceptors and palisade endings and to reconsider current knowledge of their structure and function.


Assuntos
Músculos Oculomotores , Células Receptoras Sensoriais , Animais , Músculos Oculomotores/inervação , Músculos Oculomotores/fisiologia , Mecanorreceptores , Propriocepção/fisiologia , Fusos Musculares , Mamíferos
3.
Int J Mol Sci ; 24(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446053

RESUMO

Uric acid lithiasis accounts for about 10% of all types of renal lithiasis. The most common causes of uric acid lithiasis are low urinary pH, followed by high concentration of urinary uric acid, and low diuresis. Treatment of patients consists of alkalinization of urine, reducing the consumption of purine-rich foods, and administration of xanthine oxidase inhibitors, because there are no established therapeutic inhibitors of uric acid crystallization. We recently found that theobromine inhibited uric acid crystallization in vitro, and that the increased urinary level of theobromine following its oral consumption was associated with the prevention of uric acid crystallization. In this study, we evaluated the inhibitory effects of theobromine metabolites and other methylxanthine-related compounds on uric acid crystallization. We also measured the urinary concentrations of theobromine and its metabolites in samples from healthy individuals and patients with uric acid stones and compared the extent of uric acid supersaturation and uric acid crystal formation in these different samples. Theobromine and other methylxanthines that lacked a substituent at position 1 inhibited uric acid crystallization, but other methylxanthines did not have this effect. Individuals with clinical parameters that favored uric acid crystallization did not develop uric acid crystals when theobromine and its metabolites were in the urine at high levels. Thus, theobromine and its metabolites reduced the risk of uric acid lithiasis.


Assuntos
Litíase , Nefrolitíase , Humanos , Ácido Úrico/química , Teobromina , Preparações Farmacêuticas
4.
Proc Natl Acad Sci U S A ; 116(9): 3837-3846, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30760592

RESUMO

Extraocular muscles contain two types of muscle fibers according to their innervation pattern: singly innervated muscle fibers (SIFs), similar to most skeletal muscle fibers, and multiply innervated muscle fibers (MIFs). Morphological studies have revealed that SIF and MIF motoneurons are segregated anatomically and receive different proportions of certain afferents, suggesting that while SIF motoneurons would participate in the whole repertoire of eye movements, MIF motoneurons would contribute only to slow eye movements and fixations. We have tested that proposal by performing single-unit recordings, in alert behaving cats, of electrophysiologically identified MIF and SIF motoneurons in the abducens nucleus. Our results show that both types of motoneuron discharge in relation to eye position and velocity, displaying a tonic-phasic firing pattern for different types of eye movement (saccades, vestibulo-ocular reflex, vergence) and gaze-holding. However, MIF motoneurons presented an overall reduced firing rate compared with SIF motoneurons, and had significantly lower recruitment threshold and also lower eye position and velocity sensitivities. Accordingly, MIF motoneurons could control mainly gaze in the off-direction, when less force is needed, whereas SIF motoneurons would contribute to increase muscle tension progressively toward the on-direction as more force is required. Anatomically, MIF and SIF motoneurons distributed intermingled within the abducens nucleus, with MIF motoneurons being smaller and having a lesser somatic synaptic coverage. Our data demonstrate the functional participation of both MIF and SIF motoneurons in fixations and slow and phasic eye movements, although their discharge properties indicate a functional segregation.


Assuntos
Movimentos Oculares/fisiologia , Neurônios Motores/fisiologia , Fibras Musculares Esqueléticas/fisiologia , Músculos Oculomotores/fisiologia , Animais , Gatos , Humanos , Tono Muscular/fisiologia , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Músculos Oculomotores/inervação , Movimentos Sacádicos/fisiologia
5.
Molecules ; 27(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36080228

RESUMO

Phytate has been classified as an anti-nutrient, but there are no adverse effects from the consumption of a balanced diet with 1 to 2 g of daily phytate (inositol-hexaphosphate, InsP6) as a calcium magnesium salt, the form naturally present in grains. Furthermore, recent research has shown that phytate consumption may prevent pathological calcifications, such as kidney stones and cardiovascular calcifications. However, many endogenous and exogenous enzymes can hydrolyze phytate to lower inositol phosphates (InsPs) that also have biological activity. We performed a controlled hydrolysis of phytate and identified the products (InsPs) using tandem mass spectrometry (MS/MS). The total level of all InsPs was measured using a non-specific methodology. In addition, we evaluated the effects of the InsP6 hydrolysates on calcium oxalate crystallization using scanning electron microscopy and measuring the time needed for the induction of crystallization. Our results indicate that InsP6 and its hydrolysis products functioned as effective inhibitors of calcium oxalate crystallization. Thus, even though InsP6 is hydrolyzed after consumption, the enzymatic products also have the potential to reduce pathological calcifications. Finally, although it is useful to measure the overall level of InsPs in biological fluids, such as urine, there is a need to develop simple analytical methods to quantify the level of individual InsPs.


Assuntos
Oxalato de Cálcio , Ácido Fítico , Cálcio/química , Cristalização , Fosfatos de Inositol , Magnésio , Ácido Fítico/farmacologia , Espectrometria de Massas em Tandem
6.
EMBO Rep ; 19(11)2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30249596

RESUMO

Monoubiquitination of histone H2B (to H2Bub1) is required for downstream events including histone H3 methylation, transcription, and mRNA export. The mechanisms and players regulating these events have not yet been completely delineated. Here, we show that the conserved Ran-binding protein Mog1 is required to sustain normal levels of H2Bub1 and H3K4me3 in Saccharomyces cerevisiae Mog1 is needed for gene body recruitment of Rad6, Bre1, and Rtf1 that are involved in H2B ubiquitination and genetically interacts with these factors. We provide evidence that the absence of MOG1 impacts on cellular processes such as transcription, DNA replication, and mRNA export, which are linked to H2Bub1. Importantly, the mRNA export defect in mog1Δ strains is exacerbated by the absence of factors that decrease H2Bub1 levels. Consistent with a role in sustaining H2Bub and H3K4me3 levels, Mog1 co-precipitates with components that participate in these modifications such as Bre1, Rtf1, and the COMPASS-associated factors Shg1 and Sdc1. These results reveal a novel role for Mog1 in H2B ubiquitination, transcription, and mRNA biogenesis.


Assuntos
Histonas/metabolismo , RNA Polimerase II/genética , RNA Mensageiro/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Proteína ran de Ligação ao GTP/metabolismo , Imunoprecipitação da Cromatina , Repressão Epigenética , Regulação Fúngica da Expressão Gênica , Histonas/genética , RNA Polimerase II/metabolismo , Transporte de RNA , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteína de Ligação a TATA-Box/genética , Proteína de Ligação a TATA-Box/metabolismo , Transcrição Gênica , Ubiquitinação , Proteína ran de Ligação ao GTP/genética
7.
Pain Med ; 15(9): 1619-36, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25159212

RESUMO

OBJECTIVE: Our aim was to systematically review and meta-analyze the effectiveness of therapeutic patient education for migraine. METHODS: A literature search of multiple electronic databases (MEDLINE, EMBASE, PEDro, CINAHL, and PsychINFO) was conducted to identify randomized control trials (RCTs) published in the English and Spanish languages up to and including May 2013. Two reviewers independently selected the studies, conducted the quality assessment (Delphi list), and extracted the results. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses method was used throughout the systematic review and meta-analysis. Standardized mean difference (SMD) and 95% confidence intervals (CIs) were calculated for relevant outcome measures (headache frequency, headache disability, self-efficacy, depressive symptoms, and quality of life) and pooled in a meta-analysis using the random effects model. RESULTS: Fourteen RCTs were included in the systematic review. Only nine studies were included in the meta-analysis. The median quality score was 6.14 ± 1.29 (range: 5-9). There was strong-moderate evidence for intermediate-term effectiveness of therapeutic patient education on headache frequency (five studies: N = 940, SMD = -0.24, 95% CI of -0.48 to -0.01, P = 0.03), headache disability (four studies: N = 799, SMD = -1.02, 95% CI of -1.95 to -0.08, P = 0.03), and quality of life (three studies: N = 674, SMD = 0.36, 95% CI of 0.05-0.67, P = 0.02). There was no evidence for either short-term or intermediate-term effectiveness of therapeutic patient education on self-efficacy or depressive symptoms. CONCLUSION: This systematic review revealed strong-moderate evidence for intermediate-term effectiveness of therapeutic patient education for migraine. Further high-quality RCTs are required for conclusive determination of its effectiveness.


Assuntos
Transtornos de Enxaqueca/psicologia , Educação de Pacientes como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Adaptação Psicológica , Analgésicos/uso terapêutico , Terapia Comportamental , Biorretroalimentação Psicológica , Terapia Combinada , Aconselhamento , Depressão/etiologia , Depressão/terapia , Avaliação da Deficiência , Humanos , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/terapia , Educação de Pacientes como Assunto/métodos , Qualidade de Vida , Projetos de Pesquisa , Autoeficácia , Materiais de Ensino , Resultado do Tratamento
8.
J Homosex ; 71(4): 934-957, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36625558

RESUMO

LGBTQ+ people tend to experience prejudice, stigma, and discrimination, which increases their risk of developing mental health difficulties. Support networks, including companion animals, can be used to cope with these challenges. We performed a systematic review of studies related to the effects of human-animal interactions on the LGBTQ+ population. The review included 18 empirical studies; the findings showed that participants tended to view companion animals as family members, as well as providers of love, acceptance, and social support. Thus, companion animals could alleviate stress and increase resilience. However, certain costs were also cited and, under some circumstances, poorer health was observed. The results are discussed considering three unique aspects of the "LGBTQ+ people-animal bond": (1) it promotes self-acceptance, (2) provides a sense of protection against sexuality-based stigma and social acts of aggression based on sex or gender, and (3) exposes animal guardians requesting animal care services to potential discrimination. By characterizing the LGBTQ+ people-animal bond, more effective responses to meet their needs and promote inclusion may be achieved.


Assuntos
Minorias Sexuais e de Gênero , Humanos , Animais , Animais de Estimação , Comportamento Sexual/psicologia , Sexualidade/psicologia , Identidade de Gênero
9.
Biomolecules ; 13(7)2023 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-37509097

RESUMO

Pathological calcifications may consist of calcium oxalate (CaOx), hydroxyapatite (HAP), and brushite (BRU). The objective of this study was to evaluate the effect of phytate (inositol hexakisphosphate, InsP6), InsP6 hydrolysates, and individual lower InsPs (InsP5, InsP4, InsP3, and InsP2) on the crystallization of CaOx, HAP and BRU in artificial urine. All of the lower InsPs seem to inhibit the crystallization of calcium salts in biological fluids, although our in vitro results showed that InsP6 and InsP5 were stronger inhibitors of CaOx crystallization, and InsP5 and InsP4 were stronger inhibitors of BRU crystallization. For the specific in vitro experimental conditions we examined, the InsPs had very weak effects on HAP crystallization, although it is likely that a different mechanism is responsible for HAP crystallization in vivo. For example, calciprotein particles seem to have an important role in the formation of cardiovascular calcifications in vivo. The experimental conditions that we examined partially reproduced the in vivo conditions of CaOx and BRU crystallization, but not the in vivo conditions of HAP crystallization.


Assuntos
Oxalato de Cálcio , Ácido Fítico , Durapatita/química , Cristalização , Inositol 1,4,5-Trifosfato , Cálcio
10.
Neural Regen Res ; 18(8): 1691-1696, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36751781

RESUMO

Vascular endothelial growth factor (VEGF) was discovered by its angiogenic activity. However, during evolution, it appeared earlier as a neurotrophic factor required for the development of the nervous system in invertebrates lacking a circulatory system. We aimed at reviewing recent evidence indicating that VEGF has neuroprotective effects in neurons exposed to a variety of insults. Of particular interest is the link established between VEGF and motoneurons, especially after the design of the VEGFδ/δ mutant mice. These mice are characterized by low levels of VEGF and develop muscle weakness and motoneuron degeneration resembling amyotrophic lateral sclerosis. The administration of VEGF through several routes to animal models of amyotrophic lateral sclerosis delays motor impairment and motoneuron degeneration and increases life expectancy. There are new recent advances in the role of VEGF in the physiology of motoneurons. Our experimental aims use the extraocular (abducens) motoneurons lesioned by axotomy as a model for studying VEGF actions. Axotomized abducens motoneurons exhibit severe alterations in their discharge activity and a loss of synaptic boutons. The exogenous administration of VEGF to axotomized abducens motoneurons, either from the transected nerve or intraventricularly, fully restores the synaptic and discharge properties of abducens motoneurons, despite being axotomized. In addition, when an anti-VEGF neutralizing antibody is delivered from the muscle to intact, uninjured abducens motoneurons, these cells display alterations in their discharge pattern and a loss of synaptic boutons that resemble the state of axotomy. All these data indicate that VEGF is an essential neurotrophic factor for motoneurons.

11.
Brain Struct Funct ; 228(3-4): 967-984, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37005931

RESUMO

The potassium chloride cotransporter 2 (KCC2) is the main Cl- extruder in neurons. Any alteration in KCC2 levels leads to changes in Cl- homeostasis and, consequently, in the polarity and amplitude of inhibitory synaptic potentials mediated by GABA or glycine. Axotomy downregulates KCC2 in many different motoneurons and it is suspected that interruption of muscle-derived factors maintaining motoneuron KCC2 expression is in part responsible. In here, we demonstrate that KCC2 is expressed in all oculomotor nuclei of cat and rat, but while trochlear and oculomotor motoneurons downregulate KCC2 after axotomy, expression is unaltered in abducens motoneurons. Exogenous application of vascular endothelial growth factor (VEGF), a neurotrophic factor expressed in muscle, upregulated KCC2 in axotomized abducens motoneurons above control levels. In parallel, a physiological study using cats chronically implanted with electrodes for recording abducens motoneurons in awake animals, demonstrated that inhibitory inputs related to off-fixations and off-directed saccades in VEGF-treated axotomized abducens motoneurons were significantly higher than in control, but eye-related excitatory signals in the on direction were unchanged. This is the first report of lack of KCC2 regulation in a motoneuron type after injury, proposing a role for VEGF in KCC2 regulation and demonstrating the link between KCC2 and synaptic inhibition in awake, behaving animals.


Assuntos
Simportadores , Fator A de Crescimento do Endotélio Vascular , Animais , Ratos , Movimentos Oculares , Neurônios Motores/fisiologia , Movimentos Sacádicos , Simportadores/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Gatos
12.
Nutr Diabetes ; 13(1): 2, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36854678

RESUMO

AIM: Adiponectin, a major adipokine secreted by adipose tissue, has been shown to improve insulin sensitivity. Myo-inositol hexaphosphate (phytate; InsP6) is a natural compound that is abundant in cereals, legumes, and nuts that has demonstrated to have different beneficial properties in patients with diabetes type 2. METHODS: We performed a randomized crossover trial to investigate the impact of daily consumption of InsP6 on serum levels of adiponectin, TNF-alpha, IL-6, and IL-1beta in patients with type 2 diabetes mellitus (T2DM; n = 39). Thus, we measure serum levels of these inflammatory markers, classic vascular risk factors, and urinary InsP6 at baseline and at the end of the intervention period. RESULTS: Patients who consumed InsP6 supplements for 3 months had higher levels of adiponectin and lower HbA1c than those who did not consume InsP6. No differences were found in TNF-alpha, IL-6, and IL-1beta. CONCLUSION: This is the first report to show that consumption of InsP6 increases plasma adiponectin concentration in patients with T2DM. Consequently, our findings indicate that following a phytate-rich diet has beneficial effects on adiponectin and HbA1c concentrations and it could help to prevent or minimize diabetic-related complications.


Assuntos
Adiponectina , Diabetes Mellitus Tipo 2 , Ácido Fítico , Humanos , Adiponectina/metabolismo , Estudos Cross-Over , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas , Interleucina-6 , Ácido Fítico/farmacologia , Ácido Fítico/uso terapêutico , Fator de Necrose Tumoral alfa
13.
J Clin Med ; 12(15)2023 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-37568551

RESUMO

(1) Background: This study aimed to determine the relationship between metabolic urine conditions and the formation, severity, and composition of encrustations in ureteral stents. (2) Methods: Ninety stone-former patients requiring a double-J stent were prospectively enrolled. We collected 24 h metabolic urine samples and demographic data, including indwelling time and previous stone composition. The total deposit weight was obtained, and a macroscopic classification according to the degree of encrustation (null, low, moderate, and high) was created, allowing for intergroup comparisons. Stereoscopic and scanning electron microscopy were performed to identify the type of embedded deposits (calcium oxalate, uric acid, and infectious and non-infectious phosphates). (3) Results: In total, 70% of stents were encrusted; thereof, 42% had a moderate degree of encrustation. The most common encrustation type was calcium oxalate, but infectious phosphates were predominant in the high-encrustation group (p < 0.05). A direct correlation was observed between the purpose-built macroscopic classification and the encrustation weights (p < 0.001). Greater calciuria, uricosuria, indwelling time, and decreased diuresis were observed in stents with a higher degree of encrustation (p < 0.05). The urinary pH values were lower in patients with uric acid encrustations and higher in those with infectious phosphate encrustations (p < 0.05). When compared to non-encrusted stents, patients with calcium-oxalate-encrusted stent showed greater calciuria, phosphaturia, indwelling time, and reduced diuresis; patients with uric-acid-encrusted stent showed greater uricosuria; and patients with infectious and non-infectious phosphate encrustation showed greater urinary pH (p < 0.05). (4) Conclusions: Metabolic urine conditions play a critical role in the formation, composition, and severity of double-J stent encrustation.

14.
Enferm Infecc Microbiol Clin (Engl Ed) ; 41(8): 501-504, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36931920

RESUMO

INTRODUCTION: Human dermatophytoses are the most widespread infections caused by fungi. These are capable of invading the keratin-containing tissues of animals. Nannizzia nana (N. nana) can cause ringworm in pigs and rarely cause infections in humans. METHODS: We conducted a search using PUBMED for articles published from January 1, 1990 to March 31, 2022 to identify additional cases. The search terms used were "Microsporum nanum" and "Nannizzia nana". RESULTS: After reviewing the literature, we identified a total of 16 cases of dermatophytosis due to N. nana since 1990. In most of the patients, the clinical diagnosis was tinea corporis and the most widely used antifungals were: terbinafine and griseofulvin. CONCLUSION: N. nana is a dermatophyte species isolated infrequently in humans, but it represents a potential source of dermatophytosis in people who come into direct or indirect contact with animals and soil.

15.
Animals (Basel) ; 12(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35565611

RESUMO

Currently, domestic dogs (Canis lupus familiaris) are the most common species among companion animals. The close bond that can grow between owners and their dogs could be worn out and finally broken due to various causes. One main cause is canine behavioral problems, leading to dogs being abandoned or euthanized due to the costs faced by the owner when caring for the animal. Tools have been developed to evaluate the mental and emotional cost of caring for humans, but there is currently no validated tool for evaluating this particular problem. The objective of this study was to develop a questionnaire to evaluate caregiver burnout syndrome for owners of dogs with behavioral disorders. The methodology used consisted of drafting the tool, peer validation using the Delphi methodology and internal validation via Cronbach's alpha. Non-linear snowball sampling was used (n = 156 participants). A questionnaire with 35 questions was obtained which referred to various aspects of caregivers' lives. Regarding the description of the sample used, 50% had Low Burnout, 41% had Medium-Low Burnout and 9% had Medium-High Burnout. Furthermore, regarding the internal validation of the questionnaire, the general Cronbach's alpha coefficient was α = 0.9468. We can thus conclude that the questionnaire is valid for measuring caregiver burnout syndrome in owners of dogs with behavioral disorders.

16.
Urolithiasis ; 50(6): 737-742, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36064981

RESUMO

The use of double J ureteral stents can lead to several adverse effects, as urinary infection. Bacteria tend to colonize the stent surface, leading to the formation of bacterial biofilms. The presence of urease-producing bacteria increase the urine pH leading to the incrustation and blockage of the stent. On the other hand, these large crystalline masses function as niduses, allowing the attachment of even more bacteria and decreasing its exposure to antibiotics. The aim of this in vitro study was to assess the effect of phytate on the attachment of bacteria to the catheter surface under conditions that favor crystallization. Catheter sections were incubated in a synthetic urine medium (pH 6.5) in the presence or absence of Pseudomonas aeruginosa and phytate. Amount of calcium deposits was measured using an Arsenazo III colorimetric method and the number of attached bacteria to the stent was determined. Differences were assessed using an ANOVA with a Bonferroni post hoc test. The formation of calcium phosphate deposits (brushite and hydroxyapatite) and oxalate crystals (COM), as were as the amount of bacteria decreased when phytate was present. Thus, phytate successfully decreased bacterial adhesion by inhibiting the formation of crystalline deposits.


Assuntos
Cálcio , Ácido Fítico , Humanos , Cristalização , Urease , Arsenazo III , Fosfatos de Cálcio/química , Oxalato de Cálcio/química , Bactérias , Durapatita , Stents/efeitos adversos , Antibacterianos
17.
Neuroscientist ; : 10738584221120803, 2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36121037

RESUMO

Vascular endothelial growth factor (VEGF) is well known for its angiogenic activity, but recent evidence has revealed a neuroprotective action of this factor on injured or diseased neurons. In the present review, we summarize the most relevant findings that have contributed to establish a link between VEGF deficiency and neuronal degeneration. At issue, 1) mutant mice with reduced levels of VEGF show adult-onset muscle weakness and motoneuron degeneration resembling amyotrophic lateral sclerosis (ALS), 2) administration of VEGF to different animal models of motoneuron degeneration improves motor performance and ameliorates motoneuronal degeneration, and 3) there is an association between low plasmatic levels of VEGF and human ALS. Altogether, the results presented in this review highlight VEGF as an essential motoneuron neurotrophic factor endowed with promising therapeutic potential for the treatment of motoneuron disorders.

18.
Invest Ophthalmol Vis Sci ; 63(11): 15, 2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36255363

RESUMO

Purpose: To test whether visual experience and/or eye movements drive the postnatal development of palisade endings in extraocular muscles. Methods: In three newborn cats, the right eye was covered until 30 days from postnatal (P) day 7 (before opening their eyes), and in three cats both eyes were covered until 45 days, also from P7. To block eye movements, another seven cats received a retrobulbar injection of botulinum neurotoxin A (BoNT-A) into the left orbit at birth and survived for 45 days (three cats) and 95 days (four cats). The distal third of the rectus muscles containing the palisade endings was used for whole-mount preparation and triple-fluorescence labeling with anti-neurofilament along with (1) anti-synaptophysin and phalloidin or (2) anti-growth associated protein 43 (GAP43) and phalloidin. Immunolabeled specimens were analyzed in the confocal laser scanning microscope. Results: After unilateral and bilateral dark rearing, palisade endings were qualitatively and quantitatively equal to those from age-matched controls. After BoNT-A induced eye immobilization for 45 or 95 days, palisade endings were absent in the superior rectus and lateral rectus muscles and only present in the inferior rectus and medial rectus muscle. These BoNT-A-treated palisade endings were rudimentary and reduced in number, and the expression of the neuronal developmental protein GAP43 was significantly reduced. Conclusions: This study demonstrates that eye immobilization, but not visual deprivation, affects palisade ending development. Palisade endings develop in the first month of life, and the present findings indicate that, during this time window, palisade endings are prone to oculomotor perturbations.


Assuntos
Toxinas Botulínicas Tipo A , Movimentos Oculares , Terminações Nervosas/fisiologia , Faloidina/metabolismo , Toxinas Botulínicas Tipo A/farmacologia , Colina O-Acetiltransferase/metabolismo , Músculos Oculomotores/metabolismo
19.
Clin Chim Acta ; 519: 187-192, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33964262

RESUMO

BACKGROUND AND AIMS: Uric acid (UA) kidney stones account for 10 to 11% of all kidney stones, and this percentage has increased over time. An accurate, rapid, simple, and low-cost test is needed to distinguish urine that is susceptible and resistant to the formation of UA crystals. The aim of this paper is to develop a test to assess the risk for UA crystallization (RUAC) and to validate its utility in routine clinical practice by analysis of urine samples of UA stone formers and healthy volunteers. PATIENTS AND METHODS: Urine samples of 20 healthy adult volunteers and 54 active formers of UA stones were collected. Three samples were collected from each participant, with at least 7 days between each collection. The main lithogenic parameters for UA stones were determined, and an RUAC test was performed in all urine samples. RESULTS: Our RUAC test reliably discriminated urine that was resistant and susceptible to the formation of UA crystals. This test had high specificity (94%) and a low percentage of false negatives. CONCLUSION: The RUAC test described here had high diagnostic accuracy, low-cost, and a rapid assay time, that make this test an attractive screening tool for UA stone fomers follow-up.


Assuntos
Cálculos Renais , Ácido Úrico , Adulto , Cristalização , Testes Diagnósticos de Rotina , Humanos
20.
Nutrients ; 13(8)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34445019

RESUMO

Myo-inositol hexaphosphate (phytate; IP6) is a natural compound that is abundant in cereals, legumes, and nuts, and it can bind to crystal surfaces and disturb crystal development, acting as crystallization inhibitor. The adsorption of such inhibitors to crystal faces can also inhibit crystal dissolution. The binding of phytate to metal cofactors suggests that it could be used for treatment of osteoporosis. Our in-vitro study showed that phytate inhibits dissolution of hydroxyapatite (HAP). The effect of phytate was similar to that of alendronate and greater than that of etidronate. This led us to perform a cross-sectional study to investigate the impact of consumption of IP6 on bone mineral density (BMD) in post-menopausal women. Our data indicate that BMD and t-score of lumbar spine increased with increasing phytate consumption, and a phytate consumption higher than 307 mg/day was associated with a normal BMD (t-score > -1). These data suggest that phytate may have a protective effect in bone decalcification by adsorbing on the surfaces of HAP, and a daily consumption of phytate-rich foods (at least one serving/day of legumes or nuts) may help to prevent or minimize bone-loss disorders, such as osteoporosis. However, further studies are needed to gain a better understanding about the mechanism of inhibition of phytate in bone-related diseases (see graphical abstract).


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Doenças Ósseas/prevenção & controle , Dieta , Ácido Fítico/administração & dosagem , Absorciometria de Fóton , Alendronato/química , Conservadores da Densidade Óssea/química , Doenças Ósseas/diagnóstico por imagem , Doenças Ósseas/fisiopatologia , Estudos Transversais , Durapatita/química , Ácido Etidrônico/química , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Estudos Prospectivos , Solubilidade , Espanha
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