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1.
Metabolites ; 14(8)2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39195543

RESUMEN

Multiple short daily bouts of HIIT are more effective than single daily sessions in improving cardiometabolic and cellular adaptations in rats. We hypothesize that a short period of detraining is sufficient to abolish the superior adaptive responses to multiple versus single daily sessions of HIIT in rats. Male rats were divided into untrained, 1xHIIT, and 3xHIIT groups. Over eight weeks, the 1xHIIT group performed 115 min single daily sessions of HIIT, while the 3xHIIT group performed three 5 min sessions with 4 h intervals. After training, both groups remained sedentary for four weeks (detraining). Resting oxygen consumption (VO2), body composition, glucose/insulin tolerance, and blood pressure were recorded. After euthanasia, cardiac function/histology and gastrocnemius mitochondrial density were analyzed. After training, both 1xHIIT and 3xHIIT protocols induced similar improvements in VO2, maximal oxygen uptake (VO2max), cardiac function/hypertrophy, and gastrocnemius mitochondrial density. These effects were maintained even after detraining. Only the 3xHIIT protocol improved insulin sensitivity. After detraining, this effect was abolished. After training, both 1xHIIT and 3xHIIT protocols reduced adiposity. After detraining, the adiposity increased in both groups, with a more pronounced increase in the 3xHIIT rats. A four-week detraining period abolishes the superior adaptive responses to multiple versus single daily HIIT sessions in rats.

2.
ACS Appl Bio Mater ; 7(8): 5553-5565, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39042039

RESUMEN

Chirality plays a crucial role in the self-assembly of biomolecules in nature. Peptides show chirality-dependent conformation and self-assembly. Lipidation of peptides occurs in vivo and has recently been exploited in designed conjugates to drive self-assembly and enhance bioactivity. Here, a library of pH-responsive homochiral and heterochiral lipidated tripeptides has been designed. The designed lipopeptides comprise homochiral C16-YKK or C16-WKK (where all the amino acids are l-isomers), and two heterochiral conjugates C16-Ykk and C16-Wkk (where the two lysines are d-isomers). The self-assembly of all the synthesized lipopeptides in aqueous solution was examined using a combination of spectroscopic methods along with cryogenic-transmission electron microscopy (cryo-TEM) and small-angle X-ray scattering (SAXS). Interestingly, it was observed that at acidic pH all the lipopeptides self-assemble into micelles, whereas at basic pH the homochiral lipopeptides self-assemble into nanofibers, whereas the heterochiral lipopeptides self-assemble into nanotapes and nanotubes. A pH switch was demonstrated using a thioflavin T fluorescence probe of ß-sheet structure present in the extended structures at pH 8. We demonstrate that both chirality and pH in lipopeptides influence the self-assembly behavior of the model tripeptides, which also show promising bioactivity. Good cytocompatibility is observed in hemolytic assays and antimicrobial activity against both Gram-negative and Gram-positive bacteria is shown through the determination of minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) values and live/dead bacteria staining assay.


Asunto(s)
Antibacterianos , Materiales Biocompatibles , Lipopéptidos , Ensayo de Materiales , Pruebas de Sensibilidad Microbiana , Nanoestructuras , Tamaño de la Partícula , Concentración de Iones de Hidrógeno , Lipopéptidos/química , Lipopéptidos/farmacología , Nanoestructuras/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/síntesis química , Estructura Molecular , Estereoisomerismo , Humanos
3.
EJNMMI Phys ; 11(1): 61, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39004681

RESUMEN

BACKGROUND: Several research groups have explored the potential of scandium radionuclides for theragnostic applications due to their longer half-lives and equal or similar coordination chemistry between their diagnostic and therapeutic counterparts, as well as lutetium-177 and terbium-161, respectively. Unlike the gallium-68/lutetium-177 pair, which may show different in-vivo uptake patterns, the use of scandium radioisotopes promises consistent behaviour between diagnostic and therapeutic radiopeptides. An advantage of scandium's longer half-life over gallium-68 is the ability to study radiopeptide uptake over extended periods and its suitability for centralized production and distribution. However, concerns arise from scandium-44's decay characteristics and scandium-43's high production costs. This study aimed to evaluate the dosimetric implications of using scandium radioisotopes with somatostatin analogues against gallium-68 for PET imaging of neuroendocrine tumours. METHODS: Absorbed dose per injected activity (AD/IA) from the generated time-integrated activity curve (TIAC) were estimated using the radiopeptides [43/44/44mSc]Sc- and [68Ga]Ga-DOTATATE. The kidneys, liver, spleen, and red bone marrow (RBM) were selected for dose estimation studies. The EGSnrc and MCNP6.1 Monte Carlo (MC) codes were used with female (AF) and male (AM) ICRP phantoms. The results were compared to Olinda/EXM software, and the effective dose concentrations assessed, varying composition between the scandium radioisotopes. RESULTS: Our findings showed good agreement between the MC codes, with - 3 ± 8% mean difference. Kidneys, liver, and spleen showed differences between the MC codes (min and max) in a range of - 4% to 8%. This was observed for both phantoms for all radiopeptides used in the study. Compared to Olinda/EXM the largest observed difference was for the RBM, of 21% for the AF and 16% for the AM for scandium- and gallium-based radiopeptides. Despite the differences, our findings showed a higher absorbed dose on [43/44Sc]Sc-DOTATATE compared to its 68Ga-based counterpart. CONCLUSION: This study found that [43/44Sc]Sc-DOTATATE delivers a higher absorbed dose to organs at risk compared to [68Ga]Ga-DOTATATE, assuming equal distribution. This is due to the longer half-life of scandium radioisotopes compared to gallium-68. However, calculated doses are within acceptable ranges, making scandium radioisotopes a feasible replacement for gallium-68 in PET imaging, potentially offering enhanced diagnostic potential with later timepoint imaging.

4.
J Clin Med ; 13(13)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38999473

RESUMEN

Background: Prostate Cancer (PCa) is asymptomatic at an early stage and often painless, requiring only active surveillance. External Beam Radiotherapy (EBRT) is currently a curative option for localised and locally advanced diseases and a palliative option for metastatic low-volume disease. Although highly effective, especially in a hypofractionation scheme, 17.4% to 39.4% of all patients suffer from cancer recurrence after EBRT. But, radiographic findings also correlate with significant differences in protein expression patterns. In the PCa EBRT workflow, several imaging modalities are available for grading, staging and contouring. Using image data characterisation algorithms (radiomics), one can provide a quantitative analysis of prognostic and predictive treatment outcomes. Methods: This literature review searched for original studies in radiomics for PCa in the context of EBRT. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, this review includes 73 new studies and analyses datasets, imaging modality, segmentation technique, feature extraction, selection and model building methods. Results: Magnetic Resonance Imaging (MRI) is the preferred imaging modality for radiomic studies in PCa but Computed Tomography (CT), Positron Emission Tomography (PET) and Ultrasound (US) may offer valuable insights on tumour characterisation and treatment response prediction. Conclusions: Most radiomic studies used small, homogeneous and private datasets lacking external validation and variability. Future research should focus on collaborative efforts to create large, multicentric datasets and develop standardised methodologies, ensuring the full potential of radiomics in clinical practice.

5.
Exp Brain Res ; 242(8): 1871-1879, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38864869

RESUMEN

This study aimed to compare the effects of High-Intensity Interval Training (HIIT) performed in a single session(1xHIIT) versus three daily sessions (3xHIIT) on fitness level and behavior of aged rats. Eighteen-month-old Wistar rats were assigned to Untrained (UN), 1xHIIT, or 3xHIIT (n = 12/group). Both groups, 1xHIIT and 3xHIIT, performed 15 min of a treadmill running HIIT protocol during 8 weeks. 1xHIIT protocol consisted of a single daily session of 15 min, while the 3xHIIT performed three daily sessions of 5 min with a 4 h interval between the sessions. Morris Water Maze (MWM) task was used to evaluate spatial learning and memory. Splash test, Forced Swim test, and Elevated Plus Maze task (EPM) were used to evaluate anhedonic, depressive-like, and anxious behaviors, respectively. Rats were euthanized, and the hippocampus was harvested for western blot analyses (CaMKII and BDNF). Both HIIT protocols improved VO2max and spatial memory. Notably, only the 3xHIIT protocol attenuated anxious and depressive-like behaviors. Western blot analyses of the hippocampus revealed that both HIIT protocols increased BDNF levels. BDNF levels were higher in the 3xHIIT when compared with 1xHIIT group, and we observed increasement of the CamKII levels just in the 3x HIIT group. Therefore, this study provides evidence indicating that accumulated HIIT sessions is more effective than traditional daily HIIT sessions in improving fitness level, cognitive function, memory, inhibiting the development of mood disorders, and enhancing BDNF and CaMKII levels in the hippocampus of aged rats.


Asunto(s)
Envejecimiento , Ansiedad , Factor Neurotrófico Derivado del Encéfalo , Depresión , Entrenamiento de Intervalos de Alta Intensidad , Hipocampo , Ratas Wistar , Animales , Hipocampo/metabolismo , Ratas , Depresión/metabolismo , Depresión/terapia , Depresión/fisiopatología , Envejecimiento/fisiología , Envejecimiento/metabolismo , Ansiedad/metabolismo , Ansiedad/terapia , Ansiedad/fisiopatología , Entrenamiento de Intervalos de Alta Intensidad/métodos , Masculino , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Cognición/fisiología , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Aprendizaje por Laberinto/fisiología , Condicionamiento Físico Animal/fisiología , Memoria Espacial/fisiología
6.
J Bodyw Mov Ther ; 39: 435-440, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38876665

RESUMEN

INTRODUCTION: The single leg bridge test (SLBT) has been suggested as a clinical test to examine function, screen injury risk, and monitor the effectiveness of rehabilitation programes targeting the hamstring. This study aimed to determine the inter-day reliability and repeatability of both SLBT performance, semitendinosus (ST), and biceps femoris long head (BFlh) surface electromyography (sEMG) responses and characterise the BFlh and ST electrical activity during the SLBT performed until exhaustion in healthy individuals. METHODS: Twelve physically active young men without previous hamstring injury were tested for the number of repetitions attained, and sEMG signal median frequency and amplitude in both ST and BFlh of each lower limb, randomly in two sessions, with a seven-day interval between sessions. RESULTS: High reliability [ICC = 0.85] was found for the number of SLBT repetitions attained. Reliability of sEMG outcomes showed better results for ST (ICC = 0.62-0.91) than for BFlh (ICC = 0.39-0.81), and a high to very-high repeatability was found for both ST (ICC = 0.91-0.84) and BFlh (ICC = 0.91-0.85). sEMG median frequency decreased and amplitude increased for both BFlh (p ≤ 0.001) and ST (p ≤ 0.039) at the end of SLBT, suggesting localised fatigue. CONCLUSIONS: The SLBT performed by healthy individuals until exhaustion proved to be reliable and to induce fatigue in both BFlh and ST, where the sEMG median frequency and amplitude can be measured on different days with acceptable reliability and high repeatability, suggesting its potential future use in both practical and clinical settings.


Asunto(s)
Electromiografía , Músculos Isquiosurales , Humanos , Masculino , Electromiografía/métodos , Músculos Isquiosurales/fisiología , Reproducibilidad de los Resultados , Adulto Joven , Adulto , Prueba de Esfuerzo/métodos
7.
PLoS One ; 19(5): e0303763, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38723013

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0209393.].

8.
Curr Hypertens Rev ; 20(1): 52-56, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38258772

RESUMEN

Arterial hypertension is a multifactorial clinical condition characterized by higher blood pressure levels. The main treatment for controlling high blood pressure consists of drug therapy, but the scientific literature has been pointing to the efficiency of aerobic and resistance exercises acting in a therapeutic and/or preventive way to reduce and control the blood pressure levels. Resistance training is characterized by sets and repetitions on a given muscle segment that uses overload, such as machine weights, bars, and dumbbells. As it successfully affects a number of variables associated to practitioners' functional and physiological features as well as emotional and social variables, resistance training has been a crucial part of physical exercise programs. Several reports highlight the various adaptive responses it provides, with a focus on the improvement in strength, balance, and muscular endurance that enables a more active and healthy lifestyle. Resistance training programs that are acute, sub-chronic, or chronic can help people with varying ages, conditions, and pathologies reduce their arterial hypertension. However, molecular mechanisms associated with resistance training to reduce blood pressure still need to be better understood. Thus, we aimed to understand the main effects of resistance training on blood pressure as well as the associated molecular mechanisms.


Asunto(s)
Presión Sanguínea , Hipertensión , Entrenamiento de Fuerza , Humanos , Hipertensión/fisiopatología , Hipertensión/terapia , Hipertensión/prevención & control , Hipertensión/diagnóstico , Presión Sanguínea/efectos de los fármacos , Resultado del Tratamiento , Músculo Esquelético/fisiopatología , Fuerza Muscular , Animales
9.
Antibiotics (Basel) ; 13(1)2024 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-38247637

RESUMEN

Antimicrobial peptides have been developed based on plant-derived molecular scaffolds for the treatment of infectious diseases. Chenopodin is an abundant seed storage protein in quinoa, an Andean plant with high nutritional and therapeutic properties. Here, we used computer- and physicochemical-based strategies and designed four peptides derived from the primary structure of Chenopodin. Two peptides reproduce natural fragments of 14 amino acids from Chenopodin, named Chen1 and Chen2, and two engineered peptides of the same length were designed based on the Chen1 sequence. The two amino acids of Chen1 containing amide side chains were replaced by arginine (ChenR) or tryptophan (ChenW) to generate engineered cationic and hydrophobic peptides. The evaluation of these 14-mer peptides on Staphylococcus aureus and Escherichia coli showed that Chen1 does not have antibacterial activity up to 512 µM against these strains, while other peptides exhibited antibacterial effects at lower concentrations. The chemical substitutions of glutamine and asparagine by amino acids with cationic or aromatic side chains significantly favoured their antibacterial effects. These peptides did not show significant hemolytic activity. The fluorescence microscopy analysis highlighted the membranolytic nature of Chenopodin-derived peptides. Using molecular dynamic simulations, we found that a pore is formed when multiple peptides are assembled in the membrane. Whereas, some of them form secondary structures when interacting with the membrane, allowing water translocations during the simulations. Finally, Chen2 and ChenR significantly reduced SARS-CoV-2 infection. These findings demonstrate that Chenopodin is a highly useful template for the design, engineering, and manufacturing of non-toxic, antibacterial, and antiviral peptides.

10.
J Prosthet Dent ; 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37978003

RESUMEN

STATEMENT OF PROBLEM: Patients with vascularized bone flaps from the fibula have reduced bone height, in which case a higher prosthetic abutment is needed for their implant-supported prosthesis. Although the double-flap technique seems promising, systematic reviews and meta-analyses of prospective studies are lacking. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the grafted areas of single barrel fibular flaps (SBFF) and double-barrel fibular flaps (DBFF) by considering failure rates, dental implant complications, and bone union at the osteotomy sites. MATERIAL AND METHODS: A systematic review and meta-analysis was performed in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement, population, intervention, control, and outcomes (PICO) question, and the National Health and Medical Research Council scales. The event rate of complications and failures was calculated with a confidence interval (CI) of 95%. RESULTS: A total of 13 prospective studies with 441 participants and 330 graft sites were identified. A total of 235 participants had SBFF with 445 implants, and 95 had DBFF with 164 implants. The overall combined graft failure rates were 4.2% for SBFF and 3.2% for DBFF. The complication rate was 10% for SBFF and 1.9% for DBFF. Implant failure was at 4.7% in the SBFF group and 3.4% in the DBFF group. CONCLUSIONS: Complication rates and implant failures were similar for SBFF and DBFF. Therefore, for long-term oral rehabilitation, both SBFF and DBFF are suitable procedures for mandibular reconstruction.

11.
Knee Surg Sports Traumatol Arthrosc ; 31(12): 6059-6068, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37853243

RESUMEN

PURPOSE: Studies have shown decreased match participation and shortened careers in athletes suffering Achilles tendon ruptures (ATRs), but assessment using a true performance metric is lacking. Plus/minus (PM) metrics provide a practical and objective approach to player performance assessment and are commonly used in other sports. This study aimed to quantify and compare individual player performance variations in elite football league players who sustained ATRs and returned to play within 1 year compared to those without ATRs, using a PM metric. METHODS: Player and team data were sourced from Transfermarkt.com. Male players sustaining ATRs between 2007 and 2018 were identified through injury reports. A control group (CTRL) was matched by position, age, height, and league, with a 6:1 ratio of controls to ATR subjects. The day of injury was considered "time zero". Year -1 corresponds to the 360 days preceding injury, and Year 1 to the interval between 360 and 720 days after. Performance in the player's main team was evaluated using a previously validated weighted PM metric. Only data from Year -1 and Year 1 were used for ATR versus CTRL group comparisons. Statistical significance was set at p < 0.05. RESULTS: The ATR group included 125 athletes. Data from more than 76,000 matches were analyzed. No statistically significant differences in net weighted PM metric between Year -1 and Year 1 were found. CONCLUSION: No differences were found between athletes suffering from ATRs and controls regarding the weighted PM metric. LEVEL OF EVIDENCE: III.


Asunto(s)
Tendón Calcáneo , Traumatismos del Tobillo , Fútbol , Traumatismos de los Tendones , Humanos , Masculino , Fútbol/lesiones , Tendón Calcáneo/lesiones , Traumatismos de los Tendones/cirugía
12.
Rejuvenation Res ; 26(5): 194-205, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37694594

RESUMEN

We previously demonstrated that a 50% caloric restriction (CR) from birth improves several cardiometabolic risk factors in young rats. In this study, we investigated in middle-aged rats the consequences of a 50% CR from birth on cardiometabolic risk factors, heart function/morphology, ventricular arrhythmia, and fibrillation incidence, and cardiac intracellular proteins involved with redox status and cell survival. From birth to the age of 18 months, rats were divided into an Ad Libitum (AL18) group, which had free access to food, and a CR18 group, which had food limited to 50% of that consumed by the AL18. Resting metabolic rate, blood pressure, and heart rate were recorded, and oral glucose and intraperitoneal insulin tolerance tests were performed. Blood was collected for biochemical analyses, and visceral fat and liver were harvested and weighed. Hearts were harvested for cardiac function, histological, redox status, and western blot analyses. The 50% CR from birth potentially reduced several cardiometabolic risk factors in 18-month-old rats. Moreover, compared with AL18, the CR18 group showed a ∼50% increase in cardiac contractility and relaxation, nearly three to five times less incidence of ventricular arrhythmia and fibrillation, ∼18% lower cardiomyocyte diameter, and ∼60% lower cardiac fibrosis. CR18 hearts also improved biomarkers of antioxidant defense and cell survival. Collectively, these results reveal several metabolic and cardiac antiaging effects of a 50% CR from birth in middle-aged rats.


Asunto(s)
Restricción Calórica , Corazón , Ratas , Animales , Restricción Calórica/métodos , Envejecimiento/fisiología , Arritmias Cardíacas
13.
Prev Vet Med ; 218: 105981, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37544081

RESUMEN

Giardia duodenalis is a flagellate protozoan that multiplies in the small intestine of a wide variety of hosts, animals and humans. It has a worldwide distribution, however it is considered a neglected disease by the World Health Organization (WHO). Nowadays, rabbits are being chosen as pets, especially by children. There are already reports of the occurrence of G. duodenalis in rabbits from other countries, but research has not been carried out in Brazil yet. Thus, the objective of our work was to verify the occurrence and molecularly characterize G. duodenalis that affect pet rabbits, through the polymerase chain reaction (PCR) in the northwest region of the state of São Paulo, Brazil. Fecal samples from 100 rabbits were collected, which later underwent a process of DNA extraction and amplification by nested-PCR (nPCR), using the SSU rRNA gene, and ß-giardin (bg), glutamate dehydrogenase (gdh) and triosephosphate isomerase (tpi) to determine the assemblage. A questionnaire was answered by the owners with information about gender, age, deworming, diarrhea, water source, food, place of residence and contact with other animals. From those samples, 40 were positive for G. duodenalis. Good quality of the SSU rRNA gene by nPCR were obtained from two samples. For the first time, we report the occurrence of G. duodenalis assemblage A on pet rabbits in Brazil.


Asunto(s)
Giardia lamblia , Giardiasis , Conejos , Humanos , Animales , Giardia lamblia/genética , Giardiasis/epidemiología , Giardiasis/veterinaria , Brasil/epidemiología , Genotipo , Filogenia , Heces , Tipificación de Secuencias Multilocus/veterinaria , Prevalencia
14.
Int J Biol Macromol ; 242(Pt 2): 124745, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37150376

RESUMEN

Malaria, leishmaniasis and Chagas disease are vector-borne protozoal infections with a disproportionately high impact on the most fragile societies in the world, and despite malaria-focused research gained momentum in the past two decades, both trypanosomiases and leishmaniases remain neglected tropical diseases. Affordable effective drugs remain the mainstay of tackling this burden, but toxicicty, inneficiency against later stage disease, and drug resistance issues are serious shortcomings. One strategy to overcome these hurdles is to get new therapeutics or inspiration in nature. Indeed, snake venoms have been recognized as valuable sources of biomacromolecules, like peptides and proteins, with antiprotozoal activity. This review highlights major snake venom components active against at least one of the three aforementioned diseases, which include phospholipases A2, metalloproteases, L-amino acid oxidases, lectins, and oligopeptides. The relevance of this repertoire of biomacromolecules and the bottlenecks in their clinical translation are discussed considering approaches that should increase the success rate in this arduous task. Overall, this review underlines how venom-derived biomacromolecules could lead to pioneering antiprotozoal treatments and how the drug landscape for neglected diseases may be revolutionized by a closer look at venoms. Further investigations on poorly studied venoms is needed and could add new therapeutics to the pipeline.


Asunto(s)
Enfermedad de Chagas , Leishmaniasis , Malaria , Humanos , Venenos de Serpiente/química , Péptidos/farmacología , Enfermedad de Chagas/tratamiento farmacológico , Leishmaniasis/tratamiento farmacológico
15.
Appl Radiat Isot ; 194: 110685, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36758323

RESUMEN

Individual monitoring can provide an estimate of the radioactivity present in the body of the exposed individuals. Periodic monitoring of occupationally exposed individuals is of great importance in case of accidental incorporation. Computational phantoms and Monte Carlo codes are often used to complement the calibration method of counting systems in internal dosimetry. Here, counting efficiency (CE) factors for a WBC system were calculated using MC simulations. The WBC system with a NaI(Tl) detector and the BOMAB phantom was modeled using three MC codes. After validation, the models were used to obtain CE values for a wide range of energies, and a CE curve was generated for the WBC system. To estimate the effects of anatomical differences on the measurement process, two anthropomorphic voxel phantoms were modeled using the VMC code. For the detector position with the highest CE value, the differences when comparing BOMAB results with the MaMP and Yale results were (-1 ± 6)% and (-1 ± 3)%, respectively. The results confirm that the use of the BOMAB phantom is a good approach for the calibration of the whole-body counter system. Measurements should be made at detector position with the highest CE values, and it is recommended to use the mean Monte Carlo CE values calculated in this work.


Asunto(s)
Radiometría , Recuento Corporal Total , Humanos , Recuento Corporal Total/métodos , Simulación por Computador , Radiometría/métodos , Fantasmas de Imagen , Método de Montecarlo
16.
Materials (Basel) ; 16(3)2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36770066

RESUMEN

The aim of the present study is to compare the biphasic calcium phosphate (BCP) using two different forms-(1) granules and (2) paste-in human maxillary sinus bone reconstruction as a split-mouth study using histomorphometric and immunolabeling for osteocalcin. Ten patients with bilateral maxillary posterior partial edentulism were selected in order to reconstruct bone height. They were divided into two groups: BCPG and BCP-P. After six months of bone healing, biopsies were harvested to assess the new bone formation and immunostaining for osteocalcin. The BCP g group had the following results: mean of bone formation in pristine bone 49.4 ± 21.6%, intermediate 49.4 ± 16.2%, and apical 55.3 ± 21.4%. The group BCP-P had a mean of 41.9 ± 17.3% in the pristine bone region, 37.5 ± 7.8% for intermediate, and 39.0 ± 13.5% for apical. The osteocalcin immunolabeling was high for both groups, demonstrating bone calcification. Thus, the two biomaterials present suitable results for the placement of dental implants.

17.
Appl Radiat Isot ; 191: 110526, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36401987

RESUMEN

The radiopharmaceuticals most commonly used in nuclear medicine are 18F-FDG and 99mTc-DMSA, both of which are administered to paediatric and adult patients using the same time activity coefficient. However, the IAEA recommends specific paediatric dosimetry. The aim of this work (TW) was to estimate the absorbed dose for 18F-FDG and 99mTc-DMSA using two paediatric voxel phantoms (Baby and Child) by Monte Carlo techniques. Biokinetic data for both radiopharmaceuticals were obtained from ICRP 128. In addition, the new time-integrated activity coefficient (TIAC) values from a recent publication were examined for the following organs: Brain, urinary bladder wall, liver, heart wall, and lung. The absorbed dose per injected activity (AD/IA) and effective dose per injected activity (E/IA) values were calculated for both phantoms and the results were compared with simulated data of paediatric phantoms from ICRP 128, MIRDcalc software and available literature. Regarding AD/IA in organs, differences of up to 61% and 115% were found for the Baby phantom and 120% and 167% for the Child phantom using 18F-FDG and 99mTc-DMSA, respectively. For FDG using the new TIAC, a maximum difference of 244% was observed. For E/IA, the maximum differences were 27% and 31% for the Baby and Child phantoms, respectively, for FDG and DSMA. In this study, new dosimetric data were calculated using Baby and Child phantoms and the newly recommended TIAC.


Asunto(s)
Fluorodesoxiglucosa F18 , Radiofármacos , Adulto , Lactante , Humanos , Niño , Método de Montecarlo , Fantasmas de Imagen , Succímero
18.
Psychol Health Med ; 28(1): 232-240, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35505523

RESUMEN

The suspension of social activities combined with health insecurity, uncertainty and fear of COVID-19 may influence physical activity practice. We aimed to investigate the relationship between the fear of COVID-19 and anxiety on physical activity patterns during the pandemic period. This cross-sectional study was performed in a sample of 520 Brazilian participants recruited by online sampling and snowball method. We assessed demographic variables, health perceptions, anxiety, fear of COVID-19 and physical activity characteristics. Both fear scores and anxiety were higher in woman (p < 0.0001). We observed a remarkable reduction in the frequency and intensity of physical activity and a modification in the exercise practice environment (from gym or sports centers to home-based physical activity) (p < 0.05). Sedentary (sitting) behavior increased during pandemic both in the weekdays and in the weekend (p < 0.0001). Participants who have never been infected were more prone of being classified in higher levels for physical activity (OR: 1.916, CI = 1.043-3.521) versus those who were previously infected (p = 0.05). Participants with a low or moderate level of physical activity before the pandemic presented lower chances of being classified as high physical activity level during the pandemic in comparison to those with high level before pandemic (p < 0.001). The Fear of Covid-19 score was negatively associated with the physical activity level (the higher the fear, the lower the level of physical activity); that is, for every increase in scale score, the odds of vigorous physical activity decreased 3%. In conclusion, fear of COVID-19 and previous contact with the virus negatively influenced physical activity practice.


Asunto(s)
COVID-19 , Femenino , Humanos , Brasil/epidemiología , Estudios Transversales , COVID-19/epidemiología , Miedo , Ejercicio Físico
19.
Appl Radiat Isot ; 192: 110547, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36470157

RESUMEN

The biodistribution of radiotracer peptide KETO[18F]FDG-VAP-P1 was evaluated by ex vivo radiation count in organs and in vivo PET imaging of healthy mice. The peptide was quickly eliminated by the kidneys. The local inflammation caused by a sterile polyurethane sponge was evaluated by PET images. In addition, dosimetry estimates of KETO[18F]FDG-VAP-P1 tracer are determined for mice using Monte Carlo simulations. Thus, the results of this study indicate that KETO[18F]FDG-VAP-P1 is a potential radiotracer for inflammation imaging.


Asunto(s)
Fluorodesoxiglucosa F18 , Inflamación , Ratones , Animales , Distribución Tisular , Inflamación/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Péptidos
20.
Nanomaterials (Basel) ; 14(1)2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38202556

RESUMEN

This study explores an eco-friendly approach to synthesizing silver nanoparticles (AgNPs) using soybean leaf extracts, employing a reaction with silver nitrate at 65 °C for 2.5 h. Optimal results were achieved at extract concentrations of 3.12 and 6.25 mg of the leaf mL-1, termed 3.12AgNP and 6.25AgNP, respectively. UV-Vis spectrophotometric analysis between 350 and 550 nm exhibited a peak at 410-430 nm, along with a color transition in the suspensions from pale yellow to brown, indicating successful synthesis. Dynamic light scattering (DLS) further delineated the favorable properties of these AgNPs, including nanometric dimensions (73-104 nm), negative charge, and moderate polydispersity, portraying stable and reproducible synthesis reactions. The bioreduction mechanism, possibly expedited by leaf extract constituents such as amino acids, phenolic acids, and polysaccharides, remains to be fully elucidated. Notably, this study underscored the potent nematicidal effectiveness of biosynthesized AgNPs, especially 6.25AgNP, against Pratylenchus brachyurus, which is a common plant-parasitic nematode in tropical soybean cultivation regions. In vitro tests illustrated significant nematicidal activity at concentrations above 25 µmol L-1, while in vivo experiments displayed a pronounced nematode population diminishment in plant roots, particularly with a 6.25AgNP rhizosphere application at concentrations of 500 µmol L-1 or twice at 250 µmol L-1, attaining a reproduction factor below 1 without any morphological nematode alterations. This research highlights the potential of 6.25AgNPs derived from soybean leaf extracts in forging sustainable nematicidal solutions, marking a significant stride toward eco-friendly phytonematode management in soybean cultivation. This novel methodology signals a promising avenue in harnessing botanical resources for nematode control and propelling a greener agricultural horizon.

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