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1.
Braz J Med Biol Res ; 57: e13913, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39166608

RESUMEN

Considering the lack of consensus related to the impact of selective IL-6 receptor inhibition on bone remodeling and the scarcity of reports, especially on large bone defects, this study proposed to evaluate the biological impact of the selective inhibitor of interleukin-6 receptor (tocilizumab) in an experimental model of critical calvarial defect in rats. In this preclinical and in vivo study, 24 male Wistar rats were randomly divided into two groups (n=12/group): defect treated with collagen sponge (CG) and defect treated with collagen sponge associated with 2 mg/kg tocilizumab (TCZ). The defect in the parietal bone was created using an 8-mm diameter trephine drill. After 90 days, the animals were euthanized, and tissue samples (skull caps) were evaluated through micro-CT, histological, immunohistochemistry, cytokines, and RT-qPCR analyses. Tocilizumab reduced mononuclear inflammatory infiltration (P<0.05) and tumor necrosis factor (TNF)-α levels (P<0.01) and down-regulated tissue gene expression of BMP-2 (P<0.001), RUNX-2 (P<0.05), and interleukin (IL)-6 (P<0.05). Moreover, it promoted a stronger immunostaining of cathepsin and RANKL (P<0.05). Micro-CT and histological analyses revealed no impact on general bone formation (P>0.05). The bone cells (osteoblasts, osteoclasts, and osteocytes) in the defect area were similar in both groups (P>0.05). Tocilizumab reduced inflammatory cytokines, decreased osteogenic protein, and increased proteases in a critical bone defect in rats. Ninety days after the local application of tocilizumab in the cranial defect, we did not find a significant formation of bone tissue compared with a collagen sponge.


Asunto(s)
Citocinas , Modelos Animales de Enfermedad , Ratas Wistar , Receptores de Interleucina-6 , Cráneo , Animales , Masculino , Citocinas/metabolismo , Receptores de Interleucina-6/antagonistas & inhibidores , Cráneo/efectos de los fármacos , Ratas , Anticuerpos Monoclonales Humanizados/farmacología , Anticuerpos Monoclonales Humanizados/uso terapéutico , Microtomografía por Rayos X , Péptido Hidrolasas/metabolismo , Inmunohistoquímica , Distribución Aleatoria
2.
Sci Rep ; 14(1): 18884, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143308

RESUMEN

Silicon-based two-dimensional (2D) materials have garnered significant attention due to their unique properties and potential applications in electronics, optoelectronics, and other advanced technologies. Here, we present a comprehensive investigation of a novel silicon allotrope, Popsilicene (Pop-Si), derived from the structure of Popgraphene. Using density functional theory and ab initio molecular dynamics simulations, we explore the thermal stability, mechanical and electronic properties, and optical characteristics of Pop-Si. Our results demonstrate that Pop-Si exhibits good thermal stability at 1000 K. Electronic structure calculations reveal that Pop-Si is metallic, with a high density of states at the Fermi level. Furthermore, our analysis of the optical properties indicates that Pop-Si has pronounced UV-Vis optical activity, making it a promising candidate for optoelectronic devices. Mechanical property assessments show that Pop-Si has Young's modulus ranging from 10 to 92 GPa and a Poisson's ratio of 0.95. These results combined suggest its potential for practical applications.

5.
World J Urol ; 42(1): 416, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39014127

RESUMEN

PURPOSE: Protocol description for renal perfusion study using thermographic technology and description of the thermographic and clinical behavior of the transplanted kidneys before and after unclamping. METHODS: Infrared thermographic images of renal grafts are obtained before kidney reperfusion, 10 min after and just before closing the surgical wound. Thermographic data is evaluated together with the type of graft and donor, cold ischemia time, hypovascularized areas determined by the surgeon during surgical intervention, alterations in vascular flow in postoperative echo-Doppler, time at the beginning of graft function and serum creatinine monitoring during postoperative follow-up. RESULTS: 17 grafts were studied. The mean temperature of the grafts before reperfusion, 10 min after and at the end of the surgery were 18.7 °C (SD 6.27), 32.36 °C (SD1.47) and 32.07 °C (SD1.78) respectively. 4 grafts presented hypoperfused areas after reperfusion. These areas presented a lower temperature compared to the well perfused parenchyma surface using thermographic images. CONCLUSION: The study of the usefulness and applicability of thermography can allow the development of tools that provide additional objective information on organ perfusion in real time and non-invasive manner. Our protocol and initial results can contribute to provide new evidence. Further analyses should be developed to shed light on the role of this technology.


Asunto(s)
Trasplante de Riñón , Termografía , Termografía/métodos , Humanos , Masculino , Persona de Mediana Edad , Femenino , Riñón/irrigación sanguínea , Riñón/diagnóstico por imagen , Adulto , Rayos Infrarrojos , Protocolos Clínicos , Perfusión/métodos , Anciano , Isquemia Fría , Reperfusión/métodos
6.
Molecules ; 29(13)2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38999170

RESUMEN

The syntheses, coordination chemistry, and Mössbauer spectroscopy of hepta-iron(III) complexes using derivatised salicylaldoxime ligands from two categories; namely, 'single-headed' (H2L) and 'double-headed' (H4L) salicylaldoximes are described. All compounds presented here share a [Fe3-µ3-O] core in which the iron(III) ions are µ3-hydroxo-bridged in the complex C1 and µ3-oxo-bridged in C2 and C3. Each compound consists of 2 × [Fe3-µ3-O] triads that are linked via a central [Fe(µ2-OH)6]3- ion. In addition to the charge balance and microanalytical evidence, Mössbauer measurements support the fact that the triads in C1 are µ3-OH bridged and are µ3-O bridged in C2 and C3.

7.
8.
Acta Trop ; 258: 107333, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39067841

RESUMEN

To evaluate the prevalence of Mycobacterium leprae and Mycobacterium lepromatosis in road killed armadillos identified along Brazilian regions, samples of liver, spleen, muscle, ear, nose and tail were collected on highways from 78 animals. The armadillos were of four different species, Cabassous tatouay, Dasypus novemcinctus, Dasypus septemcinctus and Euphractus sexcinctus. After DNA extraction from two tissues, specific primers were used for the detection of each pathogen using SYBR green qualitative Real-Time PCR, and amplicons were sequenced. The species with the highest prevalence was D. novemcinctus, mainly in the Central-West, South, and Southeast regions of Brazil. We detected M. leprae DNA in 32 (41 %) of the 78 individuals and M. lepromatosis DNA was not identified in any of the examined samples. The zoonotic component of leprosy may play a role in the transmission of the disease in endemic areas in which environmental conditions and contact with reservoirs must be investigated.


Asunto(s)
Armadillos , Lepra , Mycobacterium leprae , Armadillos/microbiología , Brasil/epidemiología , Animales , Mycobacterium leprae/genética , Mycobacterium leprae/aislamiento & purificación , Prevalencia , Lepra/epidemiología , Lepra/microbiología , Mycobacterium/genética , Mycobacterium/aislamiento & purificación , Mycobacterium/clasificación , ADN Bacteriano/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
9.
BMJ Mil Health ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38862249

RESUMEN

OBJECTIVES: A history of childbirth is associated with musculoskeletal injury (MSKi) in female members of the Canadian Armed Forces (CAF). While previous injury and pregnancy impact knee kinematics, it is unclear if a history of childbirth is associated with medial knee displacement (MKD) in an overhead squat movement screen. The aim of this study is to examine the relationship between MKD and (1) MSKi and (2) parity status in female CAF members. METHODS: 24 nulliparous and 21 parous female participants employed by the CAF completed a comprehensive physical fitness assessment of muscular flexibility, power, strength, endurance, aerobic capacity and a bodyweight overhead squat movement screen (recorded using two-dimensional video, and hip-knee-ankle angle measured using Kinovea software). Interactions between MKD, parity status and MSKi history were assessed by one-way analysis of variance and two-way analysis of covariance (ANCOVA) (adjusted for age). RESULTS: An interaction between parity status and acute injury of the lower extremity was observed (F=4.379, p=0.043, η2 =0.099) in MKD of the right knee. The two-way ANCOVA examining acute injury of the lumbopelvic hip complex (lower back, pelvis, hip) yielded an interaction between acute injury to the lumbopelvic hip complex and parity status (F=4.601, p=0.038, η2=0.103) in MKD asymmetry. DISCUSSION: Parous participants with acute injury to the lower extremity had larger MKD than parous without this injury type. Parous participants without acute injury to the lumbopelvic hip complex had greater MKD asymmetry than nulliparous without this injury type. Our findings suggest that researchers and clinicians should consider parity status in conjunction with MSKi history when assessing knee kinematics in female military members.

10.
Braz J Biol ; 84: e275155, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38808781

RESUMEN

Infections caused by Candida spp. are frequent in critically hospitalized patients, especially among premature neonates, representing one of the most common healthcare-related infections. Although there is considerable production of current knowledge about the mechanisms of immune response, aspects involved in the newborn's innate defense are not fully understood. The aim of this study was to describe the innate immune mechanisms involved in the defense of neonates against invasive candidiasis. This is an integrative literature review from the Scopus, Scifinder, Medline, Web of Science databases and the electronic libraries ScienceDirect and Scielo, in the period between 2002 and 2020, with rescue based on primary descriptor Immunity Innate plus secondary descriptors Candidiasis Invasive AND Infant Newborn. We have observed the involvement of various mechanisms in the neonatal response against invasive candidiasis, including the recognition, signaling, recruitment, and initiation of an effective immune response. These mechanisms encompass the presence of antimicrobial peptides, phagocytosis, synthesis of reactive oxygen species, inflammatory mediators, and complex cell signaling systems mediated by Pattern Recognition Receptors (PRRs). With this study, it is expected to contribute to the expansion of knowledge about the immunological mechanisms involved in the innate immune response of the newborn against disseminated infections caused by Candida species, and in the same sense, highlight the importance of this knowledge as a reflex in the decrease in mortality in the neonatal period.


Asunto(s)
Candidiasis Invasiva , Inmunidad Innata , Inmunidad Innata/inmunología , Humanos , Candidiasis Invasiva/inmunología , Recién Nacido
11.
Sci Rep ; 14(1): 9526, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664467

RESUMEN

The continued interest in 2D carbon allotropes stems from their unique structural and electronic characteristics, which are crucial for diverse applications. This work theoretically introduces PHOTH-Graphene (PHOTH-G), a novel 2D planar carbon allotrope formed by 4-5-6-7-8 carbon rings. PHOTH-G emerges as a narrow band gap semiconducting material with low formation energy, demonstrating good stability under thermal and mechanical conditions. This material has slight mechanical anisotropy with Young modulus and Poisson ratios varying between 7.08-167.8 GPa and 0.21-0.96. PHOTH-G presents optical activity restricted to the visible range. Li atoms adsorbed on its surface have a migration barrier averaging 0.38 eV.

12.
Artículo en Inglés | MEDLINE | ID: mdl-38428676

RESUMEN

The aim of this study is to describe the anaesthesia management of two patients undergoing carinal resection under veno-venous extracorporeal membrane oxygenation (VV ECMO). In both cases, anaesthesia was induced and then maintained with inhalational agents during pneumonectomy and mediastinoscopy (respectively). Then the jugular and femoral veins were cannulated and VV ECMO was started after heparinization. One of the patients presented bleeding during surgery, which was treated with low-dose vasopressors (norepinephrine) and transfusion of platelets, fresh frozen plasma, and concentrated red blood cells. During VV ECMO, anaesthesia was maintained with target-controlled infusion of propofol. VV ECMO can be expected to improve surgical conditions in tracheal surgery; however, it is still a novel technique in this context. In selected patients, it would guarantee ventilatory support during carinal resection, but it is essential to carefully plan anaesthesia maintenance and prepare for VV ECMO-related complications. This technique should only be used in tertiary centres with experience in VV ECMO management.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Tráquea , Humanos , Oxigenación por Membrana Extracorpórea/métodos , Masculino , Tráquea/cirugía , Persona de Mediana Edad , Femenino , Neumonectomía/métodos , Neoplasias de la Tráquea/cirugía , Anciano , Adulto , Pérdida de Sangre Quirúrgica/prevención & control
13.
Eur J Clin Pharmacol ; 80(7): 1079-1087, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38546840

RESUMEN

PURPOSE: To investigate the physicochemical compatibility of caffeine citrate and caffeine base injections with 43 secondary intravenous (IV) drugs used in Neonatal Intensive Care Unit (NICU) settings. METHODS: Caffeine citrate (20 mg/mL or 10 mg/mL) or caffeine base injection (10 mg/mL) were mixed in a volume ratio of 1:1 with the secondary drug solution to simulate Y-site co-administration procedures in NICUs. Physical compatibility was evaluated based on visual observation for 2 h, against a black and white background and under polarised light, for changes in colour, precipitation, haze and evolution of gas. Chemical compatibility was determined from caffeine concentration measurements, using a validated high-performance liquid chromatography assay. RESULTS: Six of the 43 secondary drugs tested (aciclovir, amphotericin (liposomal), furosemide, hydrocortisone, ibuprofen and ibuprofen lysine) were physically incompatible with caffeine citrate undiluted injection (20 mg/mL), at their high-end, clinically relevant concentrations for NICU settings. However, when tested at lower concentrations, hydrocortisone (1 mg/mL) was physicochemically compatible, whereas furosemide (0.2 mg/mL) was physically incompatible with caffeine citrate. The six drugs which showed physical incompatibility with caffeine citrate 20 mg/mL injection were also physically incompatible with caffeine citrate 10 mg/mL solution. All 43 secondary drugs tested were physicochemically compatible with caffeine base injection. CONCLUSIONS: Most secondary test drugs, except aciclovir, amphotericin (liposomal), furosemide, hydrocortisone, ibuprofen and ibuprofen lysine, were physicochemically compatible with caffeine citrate injection. Caffeine base injection was physicochemically compatible with all 43 test drugs tested.


Asunto(s)
Cafeína , Citratos , Incompatibilidad de Medicamentos , Cafeína/química , Cafeína/administración & dosificación , Humanos , Citratos/química , Citratos/administración & dosificación , Recién Nacido , Cuidado Intensivo Neonatal , Unidades de Cuidado Intensivo Neonatal , Aciclovir/administración & dosificación , Aciclovir/química
14.
Pharmaceutics ; 16(3)2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38543312

RESUMEN

Sildenafil is used to treat pulmonary hypertension in neonatal intensive care unit (NICU) settings. As multiple intravenous (IV) medications are co-administered in NICU settings, we sought to investigate the physicochemical compatibility of sildenafil with a range of IV drugs. Sildenafil 600 mcg/mL or 60 mcg/mL was mixed 1:1 with the secondary drug solution to simulate Y-site co-administration procedures. Physical compatibility was evaluated by visual observation against a black and white background and under polarized light for two hours for changes in colour, precipitation, haze and evolution of gas. Chemical compatibility was determined from sildenafil concentrations, using a validated, stability-indicating high-performance liquid chromatography assay. Sildenafil 600 mcg/mL was physicochemically compatible with 29 of the 45 drugs tested at 'high-end' clinical concentrations and physically incompatible with 16 drugs and six '2-in-1' parenteral nutrition solutions. Sildenafil 600 mcg/mL was compatible with lower, clinically relevant concentrations of calcium gluconate, heparin and hydrocortisone. Aciclovir, amoxicillin, ampicillin, ibuprofen lysine, indometacin, phenobarbitone and rifampicin were incompatible with sildenafil 600 mcg/mL, however these IV medications were compatible with sildenafil 60 mcg/mL. Sildenafil 600 mcg/mL and 60 mcg/mL were incompatible with amphotericin, flucloxacillin, furosemide, ibuprofen, meropenem and sodium bicarbonate. Sildenafil compatibility with commonly used syringe filters was also investigated. Sildenafil solution was compatible with nylon syringe filters, however, absorption/adsorption loss occurred with polyethersulfone and cellulose ester filters.

15.
PLoS One ; 19(3): e0292442, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38547110

RESUMEN

BACKGROUND: Although the benefits of regular physical activity (PA) after stroke are well established, many stroke survivors do not achieve recommended PA levels. To date, studies exploring determinants to PA have not used a behaviour change theory and focused on stroke survivors with physical disabilities. As a precursor to an intervention development study, we aimed to use the Theoretical Domains Framework (TDF) to identify factors influencing PA in stroke survivors with physical disabilities in Singapore. METHODS: Between November 2021 and January 2022, we conducted interviews with 19 community-dwelling stroke survivors with a weak arm and/or leg. An interview guide based on the TDF was developed. We analysed the data deductively by coding interview transcripts into the theoretical domains of the TDF, and then inductively by generating themes and belief statements. To identify relevant TDF domains, we prioritised the domains based on the frequencies of the belief statements, presence of conflicting belief statements and evidence of strong belief statements. RESULTS: Eight of the 14 TDF domains were relevant, and included environmental context and resources, knowledge, social influences, emotion, reinforcement, behavioural regulation, skills and beliefs about capabilities. The lack of access, suitable equipment and skilled help often limited PA participation at public fitness spaces such as parks, gyms and swimming pools (environmental context and resources). While a few stroke survivors expressed that they had the skills to engage in regular PA, most expressed not knowing how much and how hard to work, which exercises to do, which equipment to use and how to adapt exercises and equipment (knowledge and skills). This often left them feeling afraid to try new activities or venture out to new places for fear of the unknown or adverse events (e.g., falls) (emotion). For some, doing the activities in a group encourage them to get out and engage in PA (social influences). CONCLUSIONS: In stroke survivors with physical disabilities, environmental context and resources had a significant influence on PA participation, and this often had a spill over effect into other domains. Our results inform a complex behaviour change intervention to improve PA after stroke, and has implications for intervention design for people with physical disabilities.


Asunto(s)
Personas con Discapacidad , Ejercicio Físico , Humanos , Investigación Cualitativa , Emociones , Sobrevivientes/psicología
16.
3 Biotech ; 14(4): 94, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38444785

RESUMEN

We analyzed here the in silico biological activities of caffeine, (+)-catechin, and theobromine. For this, the PubChem database of the NIH (National Institutes of Health) was used to obtain the SMILE canonical form of the bioactive molecules, and the free software PASS Online (Prediction of Activity Spectra for Substances) from the Way2Drug portal. Also, we conducted an in vitro experiment using a chronic myeloid leukemia (CML) cell line (K562) to confirm some results found in in silico investigation. These cells were exposed to different concentrations of caffeine, (+)-catechin, and theobromine for 72 h. The results found in this in silico study suggested that caffeine, (+)-catechin, and theobromine showed excellent biological properties, such as antioxidant, anti-inflammatory, and anticarcinogenic, as well as protection against cardiovascular, diabetes, neurological, allergic, respiratory, and other therapeutic activities. These findings can be elucidated through the modulation exerted by these bioactive molecules in many biochemical pathways involved in organism homeostasis, such as free radical scavenger action, oxidoreductase inhibitor, membrane permeability inhibitor, and lipid peroxidase inhibitor. In addition, we have found here that caffeine, (+)-catechin, and theobromine have a remarkable anti-inflammatory activity which plays an important role in the therapeutic approach of COVID-19. Moreover, our in vitro findings confirmed the in silico results regarding anticancer activity since these molecules reduce cell proliferation at all tested concentrations. Therefore, since these molecules exhibit important medicinal activities, further investigations should be conducted to reveal new therapies to improve the treatments and prevention of numerous disorders and, consequently, promote human health.

17.
J Nutr Metab ; 2024: 7857489, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38504833

RESUMEN

Background: The COVID-19 pandemic is an extraordinary global emergency. The pandemic has changed profoundly people's lifestyles. This resulted in reductions in physical activity and changes in dietary intakes that have the potential to accelerate sarcopenia. Objective: The aim of this study was to evaluate the risk factors associated with acute sarcopenia in patients hospitalized with COVID-19. Methods: This was a cross-sectional study conducted from January/2021 to March/2022 in a private hospital in Cuiabá/MT, central region of Brazil. The main variable was the prevalence of acute sarcopenia among adults hospitalized with COVID19. Patients were assessed for acute sarcopenia using the SARC-F ≥4 questionnaire (strength, assistance with walking, rise from a chair, climb stairs, and falls), grip strength (<20 kg (female) and <35 kg (male)), and calf circumference (<33 cm (female) and <34 cm (male)). Results: In all, 213 patients aged 57.4 ± 15.4 years, 63.8% male, were studied. Thirty-four (16.0%) patients were diagnosed with acute sarcopenia. Advanced age (older people) and the percentage of weight lost ≥3% before hospitalization were independent risk factors for acute sarcopenia in hospitalized patients with COVID-19. Conclusion: Acute sarcopenia was present in 16% of patients. Advanced age and percentage of weight lost ≥3% were independent risk factors for acute sarcopenia in patients hospitalized with COVID-19.

20.
Artículo en Inglés | MEDLINE | ID: mdl-38174976

RESUMEN

BACKGROUND AND OBJECTIVE: To analyze the sensitization pattern to Dermatophagoides pteronyssinus and to associate the diagnostic findings and clinical severity in 218 allergic patients from two different continents. METHODS: Mite allergic patients were recruited by the Allergology departments from Latin America (n=88: Colombia, Costa Rica and Guatemala) and Spain (N=130). All patients had allergic rhinitis with or without asthma and positive skin prick test results to D. pteronyssinus. Specific IgE levels to D. pteronyssinus, D. farinae, Der p 1, Der p 2, and Der p 23 were quantified by ImmunoCAP system (ThermoFisher Scientific). Allergenic profile was also determined by western blot. Comparative Statistical analysis was performed by GraphPad software. RESULTS: Patients recognized most frequently Der p 2 (79%) followed by Der p 1 (73%), and Der p 23 (69%) allergens. The percentage of asthmatic patients increases with the number of sensitizations however none statistically significant differences were found. Interestingly, asthmatic patients presented the highest median levels of total IgE and specific IgE levels of D. pteronyssinus and molecular allergens, mainly Der p 2. Analysing the two different populations, Spanish patients were predominantly sensitized to Der p 2 (88.46%) and Der p 1 (83.84%), whereas Latin American population were more sensitized to Der p 23. CONCLUSION: Our data support the relevance of Der p 2 in mite allergy as the major allergen, with the high number of patients sensitized to it and its importance in the development of asthma. Sensitization to Der p 23 was more important in Latin America.

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