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1.
Urologia ; : 3915603231224511, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38279809

RESUMO

Urinary tract infections (UTIs) present a formidable challenge in the care of individuals affected by multiple sclerosis (MS). Lower urinary tract dysfunction is a prevalent issue among MS patients, predisposing them to an elevated risk of UTIs. When left untreated, UTIs can further exacerbate the already compromised quality of life in individuals with MS. The diagnosis and management of UTIs in MS patients necessitate a careful clinical evaluation. The objective of this review is to delineate preventive strategies and current and developing therapeutic approaches for preventing and treating UTIs associated with urinary dysfunction, catheterization, and upper urinary tract infections in patients with MS. Effectively addressing UTIs and urinary tract dysfunction in individuals with multiple sclerosis calls for a comprehensive, interdisciplinary approach.

2.
Molecules ; 28(18)2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37764313

RESUMO

The structural determination and characterization of molecules, namely proteins and enzymes, is crucial to gaining a better understanding of their role in different chemical and biological processes. The continuous technical developments in the experimental and computational resources of X-ray diffraction (XRD) and, more recently, cryogenic Electron Microscopy (cryo-EM) led to an enormous growth in the number of structures deposited in the Protein Data Bank (PDB). Bioinorganic chemistry arose as a relevant discipline in biology and therapeutics, with a massive number of studies reporting the effects of metal complexes on biological systems, with vanadium complexes being one of the relevant systems addressed. In this review, we focus on the interactions of vanadium compounds (VCs) with proteins. Several types of binding are established between VCs and proteins/enzymes. Considering that the V-species that bind may differ from those initially added, the mentioned structural techniques are pivotal to clarifying the nature and variety of interactions of VCs with proteins and to proposing the mechanisms involved either in enzymatic inhibition or catalysis. As such, we provide an account of the available structural information of VCs bound to proteins obtained by both XRD and/or cryo-EM, mainly exploring the more recent structures, particularly those containing organic-based vanadium complexes.

3.
Phys Rev Lett ; 130(19): 193601, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37243649

RESUMO

With a levitodynamics experiment in the strong and coherent quantum optomechanical coupling regime, we demonstrate that the oscillator acts as a broadband quantum spectrum analyzer. The asymmetry between positive and negative frequency branches in the displacement spectrum traces out the spectral features of the quantum fluctuations in the cavity field, which are thus explored over a wide spectral range. Moreover, in our two-dimensional mechanical system the quantum backaction, generated by such vacuum fluctuations, is strongly suppressed in a narrow spectral region due to a destructive interference in the overall susceptibility.

4.
Methods Mol Biol ; 2652: 199-213, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37093477

RESUMO

Thermal shift assay (TSA), also commonly designed by differential scanning fluorimetry (DSF) or ThermoFluor, is a technique relatively easy to implement and perform, useful in a myriad of applications. In addition to versatility, it is also rather inexpensive, making it suitable for high-throughput approaches. TSA uses a fluorescent dye to monitor the thermal denaturation of the protein under study and determine its melting temperature (Tm). One of its main applications is to identify the best buffers and additives that enhance protein stability.Understanding the TSA operating mode and the main methodological steps is a central key to designing effective experiments and retrieving meaningful conclusions. This chapter intends to present a straightforward TSA protocol, with different troubleshooting tips, to screen effective protein stabilizers such as buffers and additives, as well as data treatment and analysis. TSA results provide conditions in which the protein of interest is stable and therefore suitable to carry out further biophysical and structural characterization.


Assuntos
Corantes Fluorescentes , Proteínas , Proteínas/química , Temperatura , Estabilidade Proteica , Fluorometria/métodos , Soluções Tampão
5.
Methods Mol Biol ; 2652: 381-403, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37093488

RESUMO

Small-angle X-ray Scattering (SAXS) is a versatile and powerful technique with applications in a wide range of fields. The continuous improvements in hardware, data analysis software, and standards for validation significantly contributed to increase its popularity and, nowadays, SAXS is a well-established method. SAXS allows to study flexible and dynamic systems (e.g., proteins and other biomolecules) in solution, providing information about their size and shape. Contrary to other structural characterization methods, SAXS has no limitations on the size of the particle under study and can be used in integrated approaches to reveal important insights otherwise difficult to obtain regarding folding-unfolding, conformational changes, movement of flexible regions, and the formation of complexes.This chapter, in addition to a concise overview on the methodology, intends to systematically enumerate the main steps involved in sample preparation and data collection, processing and analysis including useful practical notes to identify and overcome common bottlenecks. This way, a less experienced user can use the content of the chapter as a starting point to properly design and perform a successful SAXS experiment.


Assuntos
Proteínas , Software , Difração de Raios X , Espalhamento a Baixo Ângulo , Raios X , Proteínas/química
6.
J Endocrinol Invest ; 46(4): 769-777, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36401759

RESUMO

INTRODUCTION: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women during reproductive age. It is characterized clinically by oligo-ovulation or anovulation, hyper-androgenism, and the presence of polycystic ovaries. Often comorbid with insulin resistance, dyslipidemia, and obesity, it also carries significant risk for the development of cardio-vascular and metabolic sequelae, including diabetes and metabolic syndrome. In light of these evidences, the most therapeutic option prescribed to PCOS women with obesity, regardless of the phenotype from the severity of clinical expression, is lifestyle correction by diet and physical activity. PURPOSE: The aim of this study was to evaluate the association between PCOS with KD in overweight and/or obese women with PCOS, and evaluate the possible beneficial effects on metabolic and endocrine parameters, compared to a standard, balanced hypocaloric diet such as Mediterranean diet (MD). METHODS: Participants were assigned to receive, in a 1:1 ratio, one of the two following dietary sequences: KD or MD. In all subjects anthropometric parameters, body composition and metabolic and endocrine parameters were obtained at baseline and after dietetic treatment. RESULTS: Our results showed a significant change in the anthropometric and biochemical parameters in both groups after both diet therapies, with statistically significant differences (p < 0.001). Though, the reductions of all parameters were significantly greater in KD group than in MD group. CONCLUSION: Our results suggest that a reduction of dietary intake of carbohydrates by KD may be considered as a valuable non-pharmacological treatment for PCOS.


Assuntos
Dieta Cetogênica , Dieta Mediterrânea , Resistência à Insulina , Síndrome do Ovário Policístico , Humanos , Feminino , Obesidade/complicações , Obesidade/terapia , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/terapia , Síndrome do Ovário Policístico/metabolismo , Sobrepeso/complicações , Sobrepeso/terapia , Dieta Redutora
7.
Int J Mol Sci ; 23(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36293152

RESUMO

Catechol-O-methyltransferase (COMT) has been involved in a number of medical conditions including catechol-estrogen-induced cancers and a great range of cardiovascular and neurodegenerative diseases such as Parkinson's disease. Currently, Parkinson's disease treatment relies on a triple prophylaxis, involving dopamine replacement by levodopa, the use of aromatic L-amino acid decarboxylase inhibitors, and the use of COMT inhibitors. Typically, COMT is highly thermolabile, and its soluble isoform (SCOMT) loses biological activity within a short time span preventing further structural and functional trials. Herein, we characterized the thermal stability profile of lysate cells from Komagataella pastoris containing human recombinant SCOMT (hSCOMT) and enzyme-purified fractions (by Immobilized Metal Affinity Chromatography-IMAC) upon interaction with several buffers and additives by Thermal Shift Assay (TSA) and a biological activity assessment. Based on the obtained results, potential conditions able to increase the thermal stability of hSCOMT have been found through the analysis of melting temperature (Tm) variations. Moreover, the use of the ionic liquid 1-butyl-3-methylimidazolium chloride [C4mim]Cl (along with cysteine, trehalose, and glycerol) ensures complete protein solubilization as well as an increment in the protein Tm of approximately 10 °C. Thus, the developed formulation enhances hSCOMT stability with an increment in the percentage of activity recovery of 200% and 70% when the protein was stored at 4 °C and -80 °C, respectively, for 12 h. The formation of metanephrine over time confirmed that the enzyme showed twice the productivity in the presence of the additive. These outstanding achievements might pave the way for the development of future hSCOMT structural and biophysical studies, which are fundamental for the design of novel therapeutic molecules.


Assuntos
Carboxiliases , Líquidos Iônicos , Doença de Parkinson , Humanos , Catecol O-Metiltransferase/genética , Catecol O-Metiltransferase/metabolismo , Levodopa/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Dopamina/uso terapêutico , Cisteína , Metanefrina , Glicerol/uso terapêutico , Trealose/uso terapêutico , Líquidos Iônicos/uso terapêutico , Catecóis/farmacologia , Catecóis/química , Estrogênios/uso terapêutico
8.
Chemistry ; 28(40): e202200105, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35486702

RESUMO

Vanadium compounds have frequently been proposed as therapeutics, but their application has been hampered by the lack of information on the different V-containing species that may form and how these interact with blood and cell proteins, and with enzymes. Herein, we report several resolved crystal structures of lysozyme with bound VIV O2+ and VIV OL2+ , where L=2,2'-bipyridine or 1,10-phenanthroline (phen), and of trypsin with VIV O(picolinato)2 and VV O2 (phen)+ moieties. Computational studies complete the refinement and shed light on the relevant role of hydrophobic interactions, hydrogen bonds, and microsolvation in stabilizating the structure. Noteworthy is that the trypsin-VV O2 (phen) and trypsin-VIV O(OH)(phen) adducts correspond to similar energies, thus suggesting a possible interconversion under physiological/biological conditions. The obtained data support the relevance of hydrolysis of VIV and VV complexes in the several types of binding established with proteins and the formation of different adducts that might contribute to their pharmacological action, and significantly widen our knowledge of vanadium-protein interactions.


Assuntos
Compostos Organometálicos , Vanádio , Compostos Organometálicos/química , Fenantrolinas , Proteínas , Tripsina , Vanádio/química , Raios X
10.
J Anesth Analg Crit Care ; 2(1): 18, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37386548

RESUMO

Cardiac complications in patients with COVID-19 have been described in the literature with an important impact on outcome. The primary objective of our systematic review was to describe the kind of cardiac complications observed in COVID-19 patients and to identify potential predictors of cardiovascular events. The secondary aim was to analyze the effect of cardiac complications on outcome.We performed this systematic review according to PRISMA guidelines using several databases for studies evaluating the type of cardiac complications and risk factors in COVID-19 patients. We also calculated the risk ratio (RR) and 95% CI. A random-effects model was applied to analyze the data. The heterogeneity of the retrieved trials was evaluated through the I2 statistic. Our systematic review included 49 studies. Acute cardiac injury was evaluated in 20 articles. Heart failure and cardiogenic shock were reported in 10 articles. Myocardial infarction was evaluated in seven of the papers retrieved. Takotsubo, myocarditis, and pericardial effusion were reported in six, twelve, and five articles, respectively. Arrhythmic complications were evaluated in thirteen studies. Right ventricular dysfunction was evaluated in six articles. We included 7 studies investigating 2115 patients in the meta-analysis. The RR was 0.20 (95% CI: 0.17 to 0.24; P < 0.00001, I2 = 0.75). Acute cardiac injury represented the prevalent cardiac complications observed in COVID-19 patients (from 20 to 45% of the patients). Patients with acute cardiac injury seemed to be significantly older, with comorbidities, more likely to develop complications, and with higher mortality rates. Acute cardiac injury was found to be an independent risk factor for severe forms of SARS-CoV-2 infection and an independent predictor of mortality. Due to the scarce evidence, it was not possible to draw any conclusion regarding Takotsubo, myocarditis, pleural effusion, and right ventricular dysfunction in COVID-19 patients. Noteworthy, possible arrhythmic alterations (incidence rate of arrhythmia from 3 to 60%) in COVID-19 patients have to be taken into account for the possible complications and the consequent hemodynamic instabilities. Hypertension seemed to represent the most common comorbidities in COVID-19 patients (from 30 to 59.8%). The prevalence of cardiovascular disease (CVD) was high in this group of patients (up to 57%), with coronary artery disease in around 10% of the cases. In the majority of the studies retrieved, patients with CVD had a higher prevalence of severe form, ICU admission, and higher mortality rates.

11.
S Afr J Sports Med ; 34(1): v34i1a11757, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36815907

RESUMO

Background: Heat shock proteins respond to a variety of physiological and environmental stresses, including heat stress, ischemia and endotoxic shock. Hormonal changes during the female menstrual cycle can have a thermogenic effect on body temperature. The monophasic oral contraceptive (OC) pill provides low doses of progesterone and oestrogen over the course of the normal menstrual phase. There is little evidence regarding the combined effects of OC on exercise performance and heat stress with respect to heat shock protein response. Objectives: This study aimed to determine the response of heat shock proteins (Hsp72) during fixed-intensity and self-paced exercise in the heat in young, healthy women on oral contraceptives compared with young healthy men. Methods: Sixteen physically active men and women performed 30 min fixed-intensity cycling at 50% of maximum workload, followed by 30 min of a self-paced time trial (TT) interspersed by 30 s maximal sprint at 9, 19 and 29 min respectively. Trials were undertaken in cool (20°C; 48±3% relative humidity (RH)) and warm (32°C; 66±2% RH) ambient conditions. Core (T c) and skin temperature, heart rate (HR) and subjective responses were measured before, during and post exercise. Results: The distance, mean and peak power output, mean and peak speed during the self-paced time trial showed no difference between the ambient temperatures for men and women. Hsp72 in females was higher than males at all sample points at both 20°C and 32°C, except for pre-exercise at 20°C (p< 0.04). Women also attained a higher T c than men at the end of the TT in the heat (38.5°C v 37.9°C for women and men, respectively; p<0.03), higher mean HR and perceived exertion. Conclusion: This study indicates that females who use oral contraceptives (OC) had higher levels of Hsp72 than males when tested under the same environmental conditions.

12.
Int J Mol Sci ; 22(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34576175

RESUMO

BACKGROUND: The STEAP1 is a cell-surface antigen over-expressed in prostate cancer, which contributes to tumor progression and aggressiveness. However, the molecular mechanisms underlying STEAP1 and its structural determinants remain elusive. METHODS: The fraction capacity of Butyl- and Octyl-Sepharose matrices on LNCaP lysates was evaluated by manipulating the ionic strength of binding and elution phases, followed by a Co-Immunoprecipitation (Co-IP) polishing. Several potential stabilizing additives were assessed, and the melting temperature (Tm) values ranked the best/worst compounds. The secondary structure of STEAP1 was identified by circular dichroism. RESULTS: The STEAP1 was not fully captured with 1.375 M (Butyl), in contrast with interfering heterologous proteins, which were strongly retained and mostly eluted with water. This single step demonstrated higher selectivity of Butyl-Sepharose for host impurities removal from injected crude samples. Co-IP allowed recovering a purified fraction of STEAP1 and contributed to unveil potential physiologically interacting counterparts with the target. A Tm of ~55 °C was determined, confirming STEAP1 stability in the purification buffer. A predominant α-helical structure was identified, ensuring the protein's structural stability. CONCLUSIONS: A method for successfully isolating human STEAP1 from LNCaP cells was provided, avoiding the use of detergents to achieve stability, even outside a membrane-mimicking environment.


Assuntos
Antígenos de Neoplasias/metabolismo , Oxirredutases/metabolismo , Neoplasias da Próstata/metabolismo , Antígenos de Neoplasias/genética , Dicroísmo Circular , Humanos , Imunoprecipitação , Masculino , Oxirredutases/genética , Neoplasias da Próstata/genética , Estabilidade Proteica , Sefarose/análogos & derivados , Sefarose/química
13.
Eur Rev Med Pharmacol Sci ; 25(14): 4678-4686, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34337715

RESUMO

OBJECTIVE: Our study aimed to confirm the expression of the endocannabinoid system in the human epithelial ovarian tumors, assessing the immunohistochemical expression of Cannabinoid Receptor Type 1 and Fatty Acid Amide Hydrolase in benign, borderline and malignant tumors. MATERIALS AND METHODS: Cannabinoid Receptor Type 1 and Fatty Acid Amide Hydrolase immunohistochemical expression was determined in 118 epithelial ovarian tumors sequentially treated during the last decade in our department: 36 benign, 34 borderline and 48 malignant neoplasms. Cannabinoid Receptor type 1 and Fatty Acid Amide Hydrolase expression resulted predominantly weak-moderate in the benign and borderline forms. RESULTS: concerning malignant tumors, Cannabinoid Receptor Type 1 expression resulted predominantly moderate-strong in Type I tumors and negative-weak in Type II tumors. Fatty Acid Amide Hydrolase expression resulted, instead, independent by the tumor types. Furthermore, there was no significant difference in the Cannabinoid Receptor Type 1 and Fatty Acid Amide Hydrolase expression relatively to the tumoral stages. CONCLUSIONS: The present study confirmed a variable expression of the endocannabinoid system in human ovarian tumors. Cannabinoid Receptor Type 1 expression was significantly different in malignant epithelial ovarian tumors according to dualistic model of ovarian carcinogenesis. Thus, in the most aggressive types II ovarian tumors, Cannabinoid Receptor Type 1 expression resulted predominantly negative or weak.


Assuntos
Carcinoma Epitelial do Ovário/metabolismo , Neoplasias Ovarianas/metabolismo , Receptor CB1 de Canabinoide/biossíntese , Carcinoma Epitelial do Ovário/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Receptor CB1 de Canabinoide/análise
14.
Eur Rev Med Pharmacol Sci ; 25(12): 4236-4246, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34227091

RESUMO

Malignant mesothelioma (MM) is a rare aggressive neoplasm arising from mesothelial lining of body cavities, most commonly pleura and peritoneum. It is characterised by a poor prognosis and limited treatment options. A universally recognised risk factor for the development of MM is exposure to asbestos. However, evidence supporting a genetic susceptibility to the development of MM has been accumulating during the last decades. Intensive research for the identification of MM susceptibility genes has led to the discovery of BAP1 and to the definition of the so-called "BAP1-related tumour predisposition syndrome". Patients carrying germline BAP1 mutations have an increased risk for the early development of tumours, including MMs, uveal melanomas, cutaneous melanocytic lesions, clear cell renal cell carcinomas and basal cell carcinomas. Furthermore, pathogenic variants in tumour suppressor genes with a role in DNA repair have been recently described in families with clustered MM cases. These genetic alterations seem to confer exaggerate sensitivity to asbestos carcinogenic effect and, arguably, increased response to specific chemotherapeutic strategies. While the translational significance of BAP1 alterations is explored in the research field, the identification of families carrying germline BAP1 mutations is mandatory to start appropriate surveillance programs and guarantee the best clinical management to these patients.


Assuntos
Predisposição Genética para Doença , Mesotelioma Maligno/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Idoso , Feminino , Mutação em Linhagem Germinativa , Humanos , Masculino , Mesotelioma Maligno/epidemiologia , Mesotelioma Maligno/patologia , Pessoa de Meia-Idade
16.
Dis Aquat Organ ; 143: 159-168, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632994

RESUMO

We investigated the cause of skeletal deformities found in brown trout from the Aspromonte mountain area in Reggio Calabria, Italy. Toxicological, histopathological and parasitological analyses were carried out on 14 fish with evident macro-morphological alterations from 2 different locations in the same river, and 4 control fish without morphological alterations from a different river (far from the first river but still within the area under study). Histopathological and radiological observations confirmed severe skeletal deformities in the specimens investigated. Parasitological examinations highlighted the presence of the nematode Cystidicoloides ephemeridarum, found only within the gastrointestinal tract of specimens showing deformities. Moreover, a direct correlation between parasite number and fish size was found. Given the low heavy metal levels and the presence of a massive parasitosis in teleosts showing deformities, we postulate a correlation between skeletal deformities and nematode infestation: the parasites caused a serious vitamin and mineral deficiency in the fish, which led to a dysplastic vertebral column. The low calcium levels found in malformed specimens compared with negative controls effectively confirm this hypothesis.


Assuntos
Doenças dos Peixes , Animais , Itália , Truta
19.
Phys Rev E ; 101(5-1): 052208, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32575292

RESUMO

Low-dimensional dynamics of large networks is the focus of many theoretical works, but controlled laboratory experiments are comparatively very few. Here, we discuss experimental observations on a mean-field coupled network of hundreds of semiconductor lasers, which collectively display effectively low-dimensional mixed mode oscillations and chaotic spiking typical of slow-fast systems. We demonstrate that such a reduced dimensionality originates from the slow-fast nature of the system and of the existence of a critical manifold of the network where most of the dynamics takes place. Experimental measurement of the bifurcation parameter for different network sizes corroborates the theory.

20.
Eur Rev Med Pharmacol Sci ; 24(7): 3829-3838, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32329859

RESUMO

OBJECTIVE: Anaplastic lymphoma kinase (ALK) gene has been demonstrated to be rearranged, mutated or amplified in several haematological and solid tumors. Moreover, the use of ALK inhibitors has recently revolutionized the treatment of ALK-rearranged patients affected by non-small cell lung carcinoma. Herein we review the genetic alterations of ALK in melanocytic neoplasms described in literature, focusing on their potential diagnostic and predictive role. MATERIALS AND METHODS: The Authors reviewed the pertinent literature through research on PubMed server was performed typing the terms "ALK", "Anaplastic lymphoma kinase", "ALKATI", "Melanoma", "Spitz", "Spitzoid". RESULTS: ALK translocations were demonstrated in melanocytic neoplasms, particularly in acral melanoma and spitzoid tumors. ALKATI was described in primary and metastatic melanoma, indicating its early occurrence in oncogenesis, with varying immunohistochemical expression of the protein. CONCLUSIONS: The identification of the specific type of ALK mutations could be interesting for planning biologic therapy of melanoma patients. Further studies are needed to evaluate the possibility to introduce an ALK-targeted therapy in patients affected by malignant melanoma.


Assuntos
Quinase do Linfoma Anaplásico/genética , Melanoma/diagnóstico , Melanoma/enzimologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/enzimologia , Quinase do Linfoma Anaplásico/análise , Quinase do Linfoma Anaplásico/metabolismo , Humanos , Melanoma/genética , Melanoma/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
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