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1.
Artigo em Inglês | MEDLINE | ID: mdl-38547699

RESUMO

In this research, a method known as a hollow fiber-liquid-phase microextraction was employed to extract and concentrate free metoprolol from plasma samples. The extracted analyte was subsequently determined using high-performance liquid chromatography coupled with a diode-array detector. Several parameters, including hollow fiber length, sonication time, extraction temperature, and salt addition, were investigated and optimized to enhance extraction efficiency. After extracting the analyte under optimum conditions from plasma samples, the enrichment factor and extraction recovery were 50 and 86 %, respectively. Moreover, the method exhibited detection and quantification limits of 0.41 and 1.30 ng mL-1, respectively. The analysis of real samples demonstrated satisfactory relative recoveries in the range of 91-99 %.


Assuntos
Microextração em Fase Líquida , Metoprolol , Microextração em Fase Líquida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cloreto de Sódio , Sonicação
2.
Adv Healthc Mater ; : e2304400, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38551206

RESUMO

The management of critical-sized bone defects presents a formidable clinical challenge, especially given the increasing incidence of bone diseases in the aging population. Consequently, there is an increased demand for minimally invasive bone repair materials that can effectively address this challenge, particularly in outpatient settings. In this study, the goal is to develop an injectable and biodegradable biomaterial that adheres to and fills bone-defect sites to support bone regeneration. The osteogenic and angiogenic activities of animal horn peptides are investigated by incorporating them into biologically active moieties, in combination with a novel thermosensitive hydrogel. The resulting thermosensitive hydrogel exhibited essential biological functionalities, allowing precise modulation of its physical and chemical properties. Notably, the hydrogel incorporating the horn peptide rapidly filled the bone defect site, promoting both angiogenesis and bone induction. Consequently, this approach significantly accelerates new bone regeneration. In summary, the findings of this study present a promising, minimally invasive solution for addressing critical-sized bone defects.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38211390

RESUMO

Tacrolimus is a potent immunosuppressive drug used in the prevention of tissue rejection. It has a narrow therapeutic index. Therefore, the determination of its concentration in biological fluids like plasma and urine is a very crucial issue. In this research, tacrolimus concentrations in plasma and urine samples were determined with a dispersive solid phase extraction procedure coupled to high-performance liquid chromatography-tandem mass spectrometry. For this purpose, a curcumin modified metal-organic framework was synthesized and used in extraction procedure. Tacrolimus was adsorbed onto the sorbent surface with aid of vortexing. Then, the adsorbed tacrolimus was eluted by a suitable solvent. Important parameters in extraction procedure were optimized by "one-variable-at-a-time" approach and reported as below: sorbent amount, 10 mg; sample solution pH, 2; agitation mode, vortexing; adsorption and desorption times, 1 min, and eluent (volume), methanol (200 µL). Under the optimized conditions and according to the International Council for Harmonization guidelines, the validation of the method was performed, and the results showed acceptable accuracy and precision (relative standard deviations ≤14 %), good linearity in a wide range (4-200 ng mL-1), and low limits of detection (1.2 ng mL-1 in plasma and 0.34 ng mL-1 in urine) and quantification (4.7 ng mL-1 in plasma and 1.12 ng mL-1 in urine). Finally, the validated method was successfully applied for the determination of tacrolimus in the plasma samples of the patients.


Assuntos
Curcumina , Estruturas Metalorgânicas , Nanocompostos , Humanos , Estruturas Metalorgânicas/química , Tacrolimo , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massa com Cromatografia Líquida , Cromatografia Líquida , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos
4.
Artigo em Inglês | MEDLINE | ID: mdl-38252747

RESUMO

A magnetic dispersive solid phase extraction method combined with solidification of floating organic droplet-based dispersive liquid-liquid microextraction has been validated for the extraction of polycyclic aromatic hydrocarbons from honey samples. For this purpose, a carbonised cellulose-ferromagnetic nanocomposite was used as a sorbent through the magnetic dispersive solid phase extraction. For preparation of the sorbent, first, carbonised cellulose nanoparticles were created by treating cellulose filter paper with concentrated solution of sulfuric acid. Then, the prepared nanoparticles were loaded onto Fe3O4 nanoparticles through coprecipitation. In the extraction process, first, a few mg of the sorbent was added to the diluted honey solution and dispersed in it using vortex agitation. The particles were then separated and the adsorbed analytes were eluted with an organic solvent. The eluent was taken and after mixing with a water-immiscible extraction solvent was used in the following solidification of floating organic droplet-based dispersive liquid-liquid microextraction procedure. By performing the extraction process under the obtained optimum conditions, low limits of detection (0.08-0.17 ng g-1) and quantification (0.27-0.57 ng g-1), satisfactory precision (relative standard deviations ≤ 5.0%), and wide linear range (0.57-500 ng g-1) with great coefficients of determination (r2≥ 0.9986) were obtained.


Assuntos
Mel , Microextração em Fase Líquida , Hidrocarbonetos Policíclicos Aromáticos , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Líquida/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Extração em Fase Sólida/métodos , Solventes , Celulose , Fenômenos Magnéticos
5.
Anal Methods ; 15(34): 4321-4330, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37606547

RESUMO

In this study, a new homogeneous liquid-liquid microextraction method using a deep eutectic solvent has been developed for the extraction of Cu(II) and Pb(II) ions in dairy products. Initially, the deep eutectic solvent was synthesized using choline chloride and p-chlorophenol and used as the extraction solvent. The synthesized solvent was soluble in milk at 70 °C and its separation from the sample was performed by decreasing the temperature. By cooling, a cloudy solution was formed due to the low solubility of the solvent at low temperatures. On centrifugation, the fine droplets of the solvent containing the analytes settled at the bottom of the tube by sedimentation. The enriched analytes were determined by flame atomic absorption spectrometry. The effect of some important parameters such as the amount of protein precipitating agent , complexing agent amount, extraction solvent volume, salt addition, pH, and temperature on the extraction efficiency of the method was studied and optimized. Under the optimal conditions, the linear ranges of the method for Cu(II) and Pb(II) ions were obtained in the ranges of 0.10-50 and 0.50-50 µg L-1 with detection limits of 0.04 and 0.18 µg L-1, respectively. The repeatability of the developed method, expressed as relative standard deviation, was determined to be 3.2 and 3.9% for Cu(II) and Pb(II) ions, respectively. Finally, by determining the concentration of Cu(II) and Pb(II) ions in milk, doogh, and cheese samples, the feasibility of the method was successfully confirmed with the extraction recoveries of 95.9 and 92.1% for Cu(II) and Pb(II) ions, respectively.


Assuntos
Cobre , Microextração em Fase Líquida , Animais , Temperatura Alta , Solventes Eutéticos Profundos , Chumbo , Leite , Íons
6.
J Sep Sci ; 46(17): e2201055, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37387553

RESUMO

This research aims to synthesize a specific and efficient sorbent to use in the extraction of apixaban from human plasma samples and its determination by high-performance liquid chromatography-tandem mass spectrometry. High specific surface area of metal-organic framework, magnetic property of iron oxide nanoparticles, selectively of molecular imprinted polymer toward the analyte, and the combination of dispersive solid-phase extraction method with a sensitive analysis system provided an efficient analytical method. In this study, first, a molecularly imprinted polymer combined with magnetic metal organic framework nanocomposite was prepared and then characterized using different techniques. Then the sorbent particles were used for selective extraction of the analyte from plasma samples. The efficiency of the method was improved by optimizing effective parameters. According to the validation results, wide linear range (1.02-200 ng mL-1 ), acceptable coefficient of determination (0.9938), low limit of detection (0.32 ng mL-1 ) and limit of quantification (1.02 ng mL-1 ), high extraction recovery (78%), and good precision (relative standard deviations ≤ 2.9% for intra- (n = 6) and interday (n = 6) precisions) were obtainable using the proposed method. These outcomes showed the high potential of the proposed method for screening apixaban in the human plasma samples.


Assuntos
Estruturas Metalorgânicas , Impressão Molecular , Humanos , Polímeros Molecularmente Impressos , Microextração em Fase Sólida/métodos , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Fenômenos Magnéticos , Impressão Molecular/métodos
7.
Spine (Phila Pa 1976) ; 48(15): 1041-1046, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37018513

RESUMO

STUDY DESIGN: Multicenter prospective observational study. OBJECTIVE: Diffusion tensor imaging in flexion extension improves the diagnosis of degenerative cervical myelopathy (DCM). We aimed to provide an imaging biomarker for the detection of DCM. SUMMARY OF BACKGROUND DATA: DCM is the most common form of spinal cord dysfunction in adults; however, imaging surveillance for myelopathy remains poorly characterized. PATIENTS AND METHODS: Symptomatic DCM patients were examined in maximum neck flexion-extension and neutral positions in a 3T-magnetic resonance imaging scanner and allocated to 2 groups: (1) Patients with visible intramedullary hyperintensity (IHIS) on T2-weighted imaging (IHIS+, n = 10); and (2) Patients without IHIS (IHIS-, n = 11). Range of motion, space available for the spinal cord, apparent diffusion coefficient (ADC), axial diffusivity (AD), radial diffusivity, and fractional anisotropy were measured and compared between the neck positions and between the groups as well as between control (C2/3) and pathologic segments. RESULTS: Significant differences between the control level (C2/3) and pathologic segments were appreciated for the IHIS+ group at neutral neck position in AD; at flexion in ADC and AD; and at neck extension in ADC, AD, and fractional anisotropy values. For the IHIS- group, significant differences between the control level (C2/3) and pathologic segments were found only for ADC values in neck extension. When comparing diffusion parameters between groups, radial diffusivity was significantly different in all 3 neck positions. CONCLUSION: Significant increases in ADC values between the control and pathologic segments were found for both groups in neck extension only. This may serve as a diagnostic tool to identify early changes in the spinal cord related to myelopathy to indicate potentially reversible spinal cord injury and support the indication for surgery in select circumstances.


Assuntos
Imagem de Tensor de Difusão , Doenças da Medula Espinal , Adulto , Humanos , Imagem de Tensor de Difusão/métodos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/patologia , Doenças da Medula Espinal/diagnóstico por imagem , Doenças da Medula Espinal/cirurgia , Doenças da Medula Espinal/patologia , Imageamento por Ressonância Magnética/métodos , Biomarcadores
8.
Int J Pharm ; 635: 122777, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36842518

RESUMO

A synthetic and thermo-responsive polymer, poly(N-isopropylacrylamide)-co-(polylactide/2-hydroxy methacrylate)-co-(oligo (ethylene glycol)), is used to formulate a universal carrier platform for sustained drug release. The enabling carrier, denoted as TP, is prepared by dissolving the polymer in an aqueous solution at a relatively neutral pH. A wide range of therapeutic moieties can be incorporated without the need for the addition of surfactants, organic solvents, and other reagents to the carrier system. The resulting solution is flowable through fine gauge needle, allowing accurate administration of TP to the target site. After injection, TP carrier undergoes a coil to globe phase transition to form a hydrogel matrix at the site. The benign nature of the polymer carrier and its physical gelation process are essential to preserve the biological activity of the encapsulated compounds while the adhesive hydrogel nature of the matrix allows sustained elusion and controlled delivery of the incorporated therapeutics. The TP carrier system has been shown to be non-toxic and elicits a minimal inflammatory response in multiple in vitro studies. These findings suggest the suitability of TP as an enabling carrier of therapeutics for localized and sustained drug delivery. To confirm this hypothesis, the capabilities of TP to encapsulate and effectively deliver multiple therapeutics of different physicochemical characteristics was evaluated. Specifically, a broad range of compounds were tested, including ciprofloxacin HCl, tumor necrosis factor-alpha (TNF-α), transforming growth factor beta 1 (TGF-ß1), and recombinant human bone morphogenetic protein 2 (BMP2). In vitro studies confirmed that TP carrier is able to control the release of the encapsulated drugs over an extended period of time and mitigate their burst release regardless of the compounds' physiochemical properties for the majority of the loaded therapeutics. Importantly, in vitro and in vivo animal studies showed that the released drugs from the TP hydrogel matrix remained potent and bioactive, confirming the high potential of the TP polymer system as an enabling carrier.


Assuntos
Hidrogéis , Medicamentos Sintéticos , Animais , Humanos , Hidrogéis/química , Polietilenoglicóis/química , Sistemas de Liberação de Medicamentos , Polímeros/química
9.
Adv Healthc Mater ; 11(23): e2201714, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36148581

RESUMO

Injectable hydrogels can support the body's innate healing capability by providing a temporary matrix for host cell ingrowth and neovascularization. The clinical adoption of current injectable systems remains low due to their cumbersome preparation requirements, device malfunction, product dislodgment during administration, and uncontrolled biological responses at the treatment site. To address these challenges, a fully synthetic and ready-to-use injectable biomaterial is engineered that forms an adhesive hydrogel that remains at the administration site regardless of defect anatomy. The product elicits a negligible local inflammatory response and fully resorbs into nontoxic components with minimal impact on internal organs. Preclinical animal studies confirm that the engineered hydrogel upregulates the regeneration of both soft and hard tissues by providing a temporary matrix to support host cell ingrowth and neovascularization. In a pilot clinical trial, the engineered hydrogel is successfully administered to a socket site post tooth extraction and forms adhesive hydrogel that stabilizes blood clot and supports soft and hard tissue regeneration. Accordingly, this injectable hydrogel exhibits high therapeutic potential and can be adopted to address multiple unmet needs in different clinical settings.


Assuntos
Hidrogéis , Hidrogéis/farmacologia
10.
Iran J Child Neurol ; 16(2): 77-84, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35497099

RESUMO

Objective: One-third of epilepsy of children is refractory, and this study was conducted to evaluate the efficacy and adverse events of levetiracetam as add-on therapy in the treatment of refractory epilepsy of children. Materials & Methods: In this quasi-experimental study, seizures frequency and side effects of 314 children aged 1-14 years with refractory epilepsy were referred to the Pediatric Neurology Clinic of Shahid Sadoughi Medical Sciences University, Yazd, Iran, and treated with levetiracetam for six months, were evaluated. Results: We evaluated 142 girls and 172 boys with a mean age of 6.78±2.12 years. At the end of six months of treatment with levetiracetam, 20% became seizure-free, 28% had more than 50% decrease in seizure frequency, 38% did not have a notable change in seizure frequency, and 14% experienced an increase in seizure frequency. Good response (stopping of all seizures or more than 50% reduction in seizure frequency) was seen in 51% of mixed types, 61% of myoclonic seizures, 64% of generalized tonic-clonic seizures, 69 % of partial seizures, 100 % of tonic seizures, and in 40 % of atonic seizures. Levetiracetam was significantly more effective in partial seizures, idiopathic epilepsies, and children with normal developmental status and normal brain MRI. Twelve children discontinued the treatment due to severe drowsiness, restlessness, and exacerbation of seizures. Transient and mild side effects, including somnolence, anorexia, fatigue, headache, ataxia, and diplopia, were seen in 9% (N=28) of patients. Conclusion: Levetiracetam could be considered an efficient and safe adjunct therapy in treating refractory epilepsy in children.

11.
Aging Cell ; 21(1): e13541, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34953016

RESUMO

Modeling age-related neurodegenerative disorders with human stem cells are difficult due to the embryonic nature of stem cell-derived neurons. We developed a chemical cocktail to induce senescence of iPSC-derived neurons to address this challenge. We first screened small molecules that induce embryonic fibroblasts to exhibit features characteristic of aged fibroblasts. We then optimized a cocktail of small molecules that induced senescence in fibroblasts and cortical neurons without causing DNA damage. The utility of the "senescence cocktail" was validated in motor neurons derived from ALS patient iPSCs which exhibited protein aggregation and axonal degeneration substantially earlier than those without cocktail treatment. Our "senescence cocktail" will likely enhance the manifestation of disease-related phenotypes in neurons derived from iPSCs, enabling the generation of reliable drug discovery platforms.


Assuntos
Neurônios Motores/metabolismo , Doenças Neurodegenerativas/genética , Diferenciação Celular , Humanos , Fenótipo
12.
BMC Geriatr ; 21(1): 654, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34798818

RESUMO

BACKGROUND: Osteosarcopenia is referred to as co-incidence of osteoporosis/osteopenia and sarcopenia which is defined as a geriatric syndrome with a significant prevalence that increases morbidity and mortality. There are some relevant factors that can show an increased risk of incidence of osteosarcopenia. AIM: We aimed to consider the association of bone turnover markers such as Osteocalcin (OC), C-terminal cross-linked telopeptide (CTX), Tartrate Resistant acid Phosphatase (TRAP), Bone Alkaline Phosphatase (BALP) and also other factors like vitamin D, calcium, phosphorous, and ALP with osteosarcopenia in elderly. METHODS: We carried out a cross-sectional study on a random sample including 400 elder participants of Bushehr Elderly Health (BEH) study, in Iran. Osteopenia/ osteoporosis was defined as a T-score ≤ -1.0 standard deviation below the mean values of a young healthy adult. We defined sarcopenia as low muscle strength (handgrip strength<26 kg for men and <18 kg for women) with reduced skeletal muscle mass [Skeletal muscle index (SMI) < 7.0 kg/m2 for male and <5.4 kg/m2 for female]. Osteosarcopenia was considered as the presence of both osteopenia/osteoporosis and sarcopenia. We estimated the age-standardized prevalence of osteosarcopenia for men and women, separately. We used multivariable logistic regression to address the factors associated with osteosarcopenia. RESULTS: The results showed that there was a statistically significant difference in OC), CTX, TRAP were between the osteosarcopenia (-) and osteosarcopenia (+) groups. No statistically significant difference was observed in BALP, vitamin D, calcium, phosphorous, and ALP between the compared groups. In the multivariable logistic regression model, OC and CTX were associated with increased likelihood of osteosarcopenia [adjusted OR= 1.023(1.002-1.045 for OC, 4.363(1.389-15.474 for CTX)]. Furthermore, TRAP increases the odds of osteosarcopenia in crude model [OR= 1.333 (1.070- 1.660)]. CONCLUSIONS: We observed the association between bone turnover markers particularly OC, CTX and osteosarcopenia. Given the rapid growth of the aging population, we should focus on geriatric diseases such as musculoskeletal disorders. Bone turnover markers maybe improve the early diagnosis, screening and assess the response to therapies in people with osteosarcopenia.


Assuntos
Densidade Óssea , Sarcopenia , Idoso , Biomarcadores , Estudos Transversais , Feminino , Força da Mão , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia
13.
Acta Biomater ; 136: 1-36, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34562661

RESUMO

Successful tissue regeneration requires a scaffold with tailorable biodegradability, tissue-like mechanical properties, structural similarity to extracellular matrix (ECM), relevant bioactivity, and cytocompatibility. In recent years, injectable hydrogels have spurred increasing attention in translational medicine as a result of their tunable physicochemical properties in response to the surrounding environment. Furthermore, they have the potential to be implanted via minimally invasive procedures while enabling deep penetration, which is considered a feasible alternative to traditional open surgical procedures. However, polymeric hydrogels may lack sufficient stability and bioactivity in physiological environments. Composite hydrogels containing bioactive glass (BG) particulates, synergistically combining the advantages of their constituents, have emerged as multifunctional biomaterials with tailored mechanical properties and biological functionalities. This review paper highlights the recent advances in injectable composite hydrogel systems based on biodegradable polymers and BGs. The influence of BG particle geometry, composition, and concentration on gel formation, rheological and mechanical behavior as well as hydration and biodegradation of injectable hydrogels have been discussed. The applications of these composite hydrogels in tissue engineering are additionally described, with particular attention to bone and skin. Finally, the prospects and current challenges in the development of desirable injectable bioactive hydrogels for tissue regeneration are discussed to outline a roadmap for future research. STATEMENT OF SIGNIFICANCE: Developing a biomaterial that can be readily available for surgery, implantable via minimally invasive procedures, and be able to effectively stimulate tissue regeneration is one of the grand challenges in modern biomedicine. This review summarizes the state-of-the-art of injectable bioactive glass-polymer composite hydrogels to address several challenges in bone and soft tissue repair. The current limitations and the latest evolutions of these composite biomaterials are critically examined, and the roles of design parameters, such as composition, concentration, and size of the bioactive phase, and polymer-glass interactions on the rheological, mechanical, biological, and overall functional performance of hydrogels are detailed. Existing results and new horizons are discussed to provide a state-of-the-art review that may be useful for both experienced and early-stage researchers in the biomaterials community.


Assuntos
Materiais Biocompatíveis , Hidrogéis , Materiais Biocompatíveis/farmacologia , Vidro , Hidrogéis/farmacologia , Engenharia Tecidual , Ciência Translacional Biomédica
14.
Int J Pediatr Otorhinolaryngol ; 150: 110902, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34488041

RESUMO

PURPOSE: Skull base defects in children may be the result of congenital anomalies or trauma. They often present as cerebrospinal fluid (CSF) rhinorrhea, meningitis, brain abscess or nasal obstruction. Surgical intervention is predominantly the treatment of choice. Our goal is to assess the efficacy of endoscopic endonasal approach in treating skull base defects in pediatric patients. MATERIAL AND METHODS: In this retrospective study we identified 38 patients (mean age 8.7 ± 5.6 years old, ranging 2 months-18 years) who underwent endoscopic endonasal repair of skull base defects, between March 2010 and February 2020. Patients who had skull base reconstruction after tumor resection, those who were lost to follow-up or did not sign the consent forms were excluded from the study. RESULTS: The clinical indications for endoscopic endonasal repair were trauma (n = 24, 63.1%) and congenital defects (n = 14, 36.9%). Congenital skull base defects included basal meningoencephalocele (n = 5, 35.7%) and frontoethmoidal defects (n = 9, 64.3%). Mean follow up time was 32 ± 29.04 months, ranging 2-103 months. Fat graft (alone or in combination) was the most commonly used material to repair the skull base defects. Thirty-seven patients (97%) showed successful results after endoscopic endonasal surgery and were symptom free. CONCLUSION: The endoscopic endonasal repair of CSF leak and skull base defects proved to be safe and feasible with 97% success rate.


Assuntos
Rinorreia de Líquido Cefalorraquidiano , Procedimentos de Cirurgia Plástica , Adolescente , Vazamento de Líquido Cefalorraquidiano/etiologia , Vazamento de Líquido Cefalorraquidiano/cirurgia , Rinorreia de Líquido Cefalorraquidiano/etiologia , Rinorreia de Líquido Cefalorraquidiano/cirurgia , Criança , Pré-Escolar , Endoscopia , Humanos , Estudos Retrospectivos , Base do Crânio/cirurgia
15.
Environ Res ; 201: 111555, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34197816

RESUMO

Several factors ranging from environmental risks to the genetics of the virus and that of the hosts, affect the spread of COVID-19. The impact of physicochemical variables on virus vitality and spread should be taken into account in experimental and clinical studies. Another avenue to explore is the effect of diet and its interaction with the immune system on SARS-CoV-2 infection and mortality rate. Past year have witnessed extensive studies on virus and pathophysiology of the COVID-19 disease and the cellular mechanisms of virus spreading. However, our knowledge has not reached a level where we plan an efficient therapeutic approach to prevent the virus entry to the cells or decreasing the spreading and morbidity in severe cases of disease. The risk of infection directly correlates with the control of virus spreading via droplets and aerosol transmission, as well as patient immune system response. A key goal in virus restriction and transmission rate is to understand the physicochemical structure of aerosol and droplet formation, and the parameters that affect the droplet-borne and airborne in different environmental conditions. The lifetime of droplets on different surfaces is described based on the contact angle. Hereby, we recommend regular use of high-quality face masks in high temperature and low humidity conditions. However, in humid and cold weather conditions, wearing gloves and frequently hand washing, gain a higher priority. Additionally, social distancing rules should be respected in all aforementioned conditions. We will also discuss different routes of SARS-CoV-2 entry into the cells and how multiple genetic factors play a role in the spread of the virus. Given the role of environmental and nutritional factors, we discuss and recommend some strategies to prevent the disease and protect the population against COVID-19. Since an effective vaccine can prevent the transmission of communicable diseases and abolish pandemics, we added a brief review of candidate SARS-CoV-2 vaccines.


Assuntos
COVID-19 , Pandemias , Vacinas contra COVID-19 , Humanos , Máscaras , SARS-CoV-2
16.
Stroke ; 52(1): 344-347, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33272133

RESUMO

BACKGROUND AND PURPOSE: The purpose of this study was to assess nationwide incidence and outcomes of aneurysmal subarachnoid hemorrhage (aSAH). The Swiss SOS (Swiss Study on Subarachnoid Hemorrhage) was established in 2008 and offers the unique opportunity to provide this data from the point of care on a nationwide level. METHODS: All patients with confirmed aneurysmal subarachnoid hemorrhage admitted between January 1, 2009 and December 31, 2014, within Switzerland were recorded in a prospective registry. Incidence rates were calculated based on time-matched population data. Admission parameters and outcomes at discharge and at 1 year were recorded. RESULTS: We recorded data of 1787 consecutive patients. The incidence of aneurysmal subarachnoid hemorrhage in Switzerland was 3.7 per 100 000 persons/y. The number of female patients was 1170 (65.5%). With a follow-up rate of 91.3% at 1 year, 1042 patients (58.8%) led an independent life according to the modified Rankin Scale (0-2). About 1 in 10 patients survived in a dependent state (modified Rankin Scale, 3-5; n=185; 10.4%). Case fatality was 20.1% (n=356) at discharge and 22.1% (n=391) after 1 year. CONCLUSIONS: The current incidence of aneurysmal subarachnoid hemorrhage in Switzerland is lower than expected and an indication of a global trend toward decreasing admissions for ruptured intracranial aneurysms. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03245866.


Assuntos
Hemorragia Subaracnóidea/epidemiologia , Hemorragia Subaracnóidea/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneurisma Roto/epidemiologia , Aneurisma Roto/mortalidade , Aneurisma Roto/terapia , Feminino , Seguimentos , Humanos , Incidência , Vida Independente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros , Fatores Sexuais , Hemorragia Subaracnóidea/mortalidade , Análise de Sobrevida , Suíça/epidemiologia , Resultado do Tratamento
17.
Am J Trop Med Hyg ; 104(2): 580-584, 2020 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-33245041

RESUMO

Hepatitis C virus (HCV) infection can affect the neurological system, and neuropathy is one of these manifestations. Hepatitis C virus infection is associated with diabetes mellitus (DM) type II, and diabetic patients are at higher risk of acquiring HCV infection. Sweat function has been proposed to assess early autonomic neuropathy. This study aimed to evaluate small fiber neuropathy in asymptomatic HCV-related cirrhotic patients with or without DM through sweat function assessment by Sudoscan test. Three groups were involved: 47 healthy controls, 48 HCV-related cirrhotic patients without DM (group 1), and 49 HCV-related cirrhotic patients with DM type II (group 2). All participants were subjected to liver panel tests, renal function tests, cell blood counts, HbA1c, and abdominal ultrasound. Sweat function was assessed in all patients and controls by measuring hand and feet electrochemical skin conductance (ESC, microSiemens [µS]) using Sudoscan. Peripheral neuropathy was detected in none of the controls, 39% of group 1 patients, and 62% of group 2 patients (P < 0.0001). The mean feet ESC (FESC) was 88.3 ± 6.8 µS in controls, 67.2 ± 19.2 µS in group 1, and 57.9 ± 19.4 µS in group 2 (P < 0.0001). A significant correlation was observed between FESC and bilirubin, albumin, creatinine, international normalized ratio, transaminases, and splenic size. Electrochemical skin conductance measurement is a valuable, noninvasive method for early detection of small fiber neuropathy in asymptomatic HCV-related cirrhosis, with or without DM.


Assuntos
Hepacivirus/patogenicidade , Hepatite C/complicações , Doenças do Sistema Nervoso Periférico/virologia , Idoso , Sistema Nervoso Autônomo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/virologia , Egito , Eletroquímica , Feminino , Pé/patologia , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Pele/patologia
18.
J Tissue Eng Regen Med ; 14(9): 1189-1200, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32721107

RESUMO

MatriDerm is a collagen-elastin dermal template that promotes regeneration in full-thickness wound repair. Due to its noncross-linked status, MatriDerm biodegrades quickly in a wound. Facilitating vascularization and dermal repair, it is desirable for MatriDerm to remain present until the wound healing process is complete, optimizing tissue regeneration and reducing wound contraction. The aim of this study was to investigate the effect of cross-linking MatriDerm on its mechanical and biological properties and to enhance its regenerative functionality. MatriDerm was chemically cross-linked and characterized in comparison with noncross-linked MatriDerm. Scaffold properties including surface morphology, protein release and mechanical strength were assessed. Cell-scaffold interaction, cell proliferation and migration were examined using human dermal fibroblasts. Scaffold biodegradation and its impact on wound healing and contraction were studied in a mouse model. Results showed that cross-linked MatriDerm displayed a small reduction in pore size, significantly less protein loss and a threefold increase in tensile strength. A significant increase in fibroblast proliferation and migration was observed in cross-linked MatriDerm with reduced scaffold contraction in vitro. In the mouse model, noncross-linked MatriDerm was almost completely biodegraded after 14 days whereas cross-linked MatriDerm remained intact. No significant difference in wound contraction was found between scaffolds. In conclusion, cross-linked MatriDerm showed a significant increase in stability and strength, enhancing its durability and cell-scaffold interaction. in vivo analysis showed cross-linked MatriDerm had a reduced biodegradation rate with a similar host response. The extended structural integrity of cross-linked MatriDerm could potentially facilitate improved skin tissue regeneration, promoting the formation of a more pliable scar.


Assuntos
Colágeno/farmacologia , Reagentes de Ligações Cruzadas/química , Derme/efeitos dos fármacos , Elastina/farmacologia , Alicerces Teciduais/química , Animais , Bovinos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Masculino , Camundongos Endogâmicos BALB C , Modelos Animais , Neovascularização Fisiológica/efeitos dos fármacos , Porosidade , Resistência à Tração
19.
J Mater Sci Mater Med ; 31(2): 21, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31989310

RESUMO

Extracellular matrix (ECM) has a major role in the structural support and cellular processes of organs and tissues. Proteins extracted from the ECM have been used to fabricate different scaffolds for tissue engineering applications. The aims of the present study were to extract, characterize and fabricate a new class of hydrogel with proteins isolated from pig bone ECM and combine them with a synthetic polymer so it could be used to promote bone regeneration. Porcine bone demineralized and digested extracellular matrix (pddECM) containing collagen type I was produced, optimized and sterilized with high pressurized CO2 method. The pddECM was further blended with 20% w/v polyethylene glycol diacrylate (PEGDA) to create an injectable semi interpenetrating polymer network (SIPN) scaffold with enhanced physicochemical properties. The blend tackled the shortfall of natural polymers, such as lack of structural stability and fast degradation, preserving its structure in more than 90% after 30 days of incubation; thus, increasing the material endurance in a simulated physiological environment. The manufactured injectable hydrogel showed high cytocompatibility with hOb and SaOs-2 cells, promoting osteogenic proliferation within 21 days of culture. The hydrogel had a high compression modulus of 520 kPa, low swelling (5.3 mg/mg) and millimetric volume expansion (19.5%), all of which are favorable characteristics for bone regeneration applications.


Assuntos
Técnica de Desmineralização Óssea , Regeneração Óssea , Osso e Ossos/química , Matriz Extracelular , Polietilenoglicóis/química , Suínos , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Colágeno Tipo I/química , Humanos , Hidrogéis , Teste de Materiais , Osteoblastos , Osteossarcoma , Alicerces Teciduais
20.
Heliyon ; 5(4): e01523, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31049434

RESUMO

Solanesol, the precursor for the synthesis of coenzyme Q10, is currently recovered from tobacco leaves by conventional extraction techniques that require multiple purification steps and a large amount of organic solvents. We recently identified tomato leaves as an alternative source of solanesol and hypothesized that a high-pressure CO2 extraction could be used as a clean extraction process. The effect of CO2 pressure and temperature on the extraction of solanesol was determined to achieve high yield and purity. It was found that solanesol could be extracted efficiently by subcritical CO2 at 25 °C from tomato leaves. The extract contained 40% solanesol and other active compounds such as vitamin K1. A higher level of purity of 93% was achieved using a secondary purification step. Different conventional methods for solanesol extraction was compared to determine the most efficient technique for production of solanesol from tomato leaf. The highest yield of solanesol was achieved at nearly 1% dry weight with using subcritical CO2, which was superior to conventional methods.

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