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1.
World J Gastroenterol ; 30(28): 3373-3385, 2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39091713

RESUMO

The perianal disease affects up to one-third of individuals with Crohn's disease (CD), causing disabling symptoms and significant impairment in quality of life, particularly for those with perianal fistulising CD (PFCD). The collaborative effort between gastroenterologists and surgeons is essential for addressing PFCD to achieve fistula closure and promote luminal healing. Limited fistula healing rates with conventional therapies have prompted the emergence of new biological agents, endoscopic procedures and surgical techniques that show promising results. Among these, mesenchymal stem cells injection is a particularly hopeful therapy. In addition to the burden of fistulas, individuals with perianal CD may face an increased risk of developing anal cancer. This underscores the importance of surveillance programmes and timely interventions to prevent late diagnoses and poor outcomes. Currently, there is no established formal anal screening programme. In this review, we provide an overview of the current state of the art in managing PFCD, including novel medical, endoscopic and surgical approaches. The discussion also focuses on the relevance of establishing an anal cancer screening programme in CD, intending to propose a risk-based surveillance algorithm. The validation of this surveillance programme would be a significant step forward in improving patient care and outcomes.


Assuntos
Neoplasias do Ânus , Doença de Crohn , Detecção Precoce de Câncer , Fístula Retal , Humanos , Neoplasias do Ânus/terapia , Neoplasias do Ânus/diagnóstico , Neoplasias do Ânus/epidemiologia , Neoplasias do Ânus/patologia , Fístula Retal/terapia , Fístula Retal/etiologia , Fístula Retal/diagnóstico , Fístula Retal/epidemiologia , Doença de Crohn/terapia , Doença de Crohn/diagnóstico , Doença de Crohn/complicações , Doença de Crohn/epidemiologia , Detecção Precoce de Câncer/métodos , Qualidade de Vida , Canal Anal/cirurgia , Canal Anal/patologia , Fatores de Risco
3.
Entropy (Basel) ; 26(7)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39056958

RESUMO

A central challenge in hypothesis testing (HT) lies in determining the optimal balance between Type I (false positive) and Type II (non-detection or false negative) error probabilities. Analyzing these errors' exponential rate of convergence, known as error exponents, provides crucial insights into system performance. Error exponents offer a lens through which we can understand how operational restrictions, such as resource constraints and impairments in communications, affect the accuracy of distributed inference in networked systems. This survey presents a comprehensive review of key results in HT, from the foundational Stein's Lemma to recent advancements in distributed HT, all unified through the framework of error exponents. We explore asymptotic and non-asymptotic results, highlighting their implications for designing robust and efficient networked systems, such as event detection through lossy wireless sensor monitoring networks, collective perception-based object detection in vehicular environments, and clock synchronization in distributed environments, among others. We show that understanding the role of error exponents provides a valuable tool for optimizing decision-making and improving the reliability of networked systems.

4.
Plants (Basel) ; 13(14)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39065470

RESUMO

The infusion of Santolina impressa, an endemic Portuguese plant, is traditionally used to treat various infections and disorders. This study aimed to assess its chemical profile by HPLC-DAD-ESI-MSn and validate its anti-inflammatory potential. In addition, the antioxidant capacity and effects on wound healing, lipogenesis, melanogenesis, and cellular senescence, all processes in which a dysregulated inflammatory response plays a pivotal role, were unveiled. The anti-inflammatory potential was assessed in lipopolysaccharide (LPS)-stimulated macrophages, cell migration was determined using a scratch wound assay, lipogenesis was assessed on T0901317-stimulated keratinocytes and melanogenesis on 3-isobutyl-1-methylxanthine (IBMX)-activated melanocytes. Etoposide was used to induce senescence in fibroblasts. Our results point out a chemical composition predominantly characterized by dicaffeoylquinic acids and low amounts of flavonols. Regarding the infusion's bioactive potential, an anti-inflammatory effect was evident through a decrease in nitric oxide production and inducible nitric oxide synthase and pro-interleukin-1ß protein levels. Moreover, a decrease in fibroblast migration was observed, as well as an inhibition in both intracellular lipid accumulation and melanogenesis. Furthermore, the infusion decreased senescence-associated ß-galactosidase activity, γH2AX nuclear accumulation and both p53 and p21 protein levels. Overall, this study confirms the traditional uses of S. impressa and ascribes additional properties of interest in the pharmaceutical and dermocosmetics industries.

5.
J Phys Chem B ; 128(29): 7022-7032, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39016210

RESUMO

The interaction between iron and amyloid-beta (Aß) peptides has received significant attention in Alzheimer's disease (AD) research due to its potential implications in developing this pathology. However, the coordination preferences of iron and Aß1-42 have not been thoroughly investigated or remain unknown. This study employs a computational protocol that combines homology modeling techniques with quantum mechanics (DTF-xTB) calculations to build and evaluate several 3D models of Fe2+/3+-Aß1-42. Our results reveal well-defined complexes for both the metal and peptide moieties, and we discuss the molecular interactions stabilizing these complexes by elucidating the coordinating environments and binding preferences. These proposed models offer valuable insights into the role of iron in Alzheimer's disease (AD) pathology.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Fragmentos de Peptídeos , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Humanos , Teoria Quântica , Modelos Moleculares , Ferro/química , Ferro/metabolismo , Compostos Férricos/química , Compostos Ferrosos/química
6.
Pediatr Hematol Oncol ; : 1-15, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007895

RESUMO

In patients with sickle cell disease (SCD) and beta-thalassemia major (TM), allogeneic hematopoietic stem cell transplantation (HSCT) was considered the only curative treatment option with a good survival rate. However, with the recent approval of gene therapies, more information is needed to understand the benefits and risks of these interventions. We performed a retrospective analysis of the Kids Inpatient Database to describe demographic features, short-term complications, and hospital charges of patients with SCD and TM treated with HSCT during 2006-2019 in the United States. The database was filtered using the International Classification of Diseases, 9th and 10th edition codes to identify children under 20 years of age with SCD or TM who underwent HSCT. A total of 513 children with SCD or TM who received HSCT were analyzed. The prevalence of HSCT per 1000,000 U.S. population increased from 0.31 in 2006 to 1.99 in 2019 (p < 0.001). The median age of children with SCD who underwent HSCT was 10 (6-15) years, and that for TM was 6 (3-11.5) years (p < 0.001). The combined mortality rate was 4% (2.4%-6.6%) but higher in the TM group. The length-of-stay and total charges were higher in the TM population (p < 0.01). This study provides national data on HSCT among hospitalized children with SCD and TM in the United States, demonstrating an increasing use of HSCT between 2006 and 2019. Although hospital mortality of HSCT in these conditions is low, it still represents a challenge, especially in TM patients.

7.
Macromol Biosci ; : e2400014, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39072995

RESUMO

Previously, a new biodegradable poly(ester urethane urea) was synthesized based on polycaprolactone-diol and fish gelatin (PU-Gel). In this work, the potential of this new material for neural tissue engineering is evaluated. Membranes with randomly oriented fibers and with aligned fibers are produced using electrospinning and characterized regarding their mechanical behavior under both dry and wet conditions. Wet samples exhibit a lower Young's modulus than dry ones and aligned membranes are stiffer and more brittle than those randomly oriented. Cyclic tensile tests are conducted and high values for recovery ratio and resilience are obtained. Both membranes exhibited a hydrophobic surface, measured by the water contact angle (WCA). Human mesenchymal stem cells from umbilical cord tissue (UC-MSCs) and human neural stem cells (NSCs) are seeded on both types of membranes, which support their adhesion and proliferation. Cells stained for the cytoskeleton and nucleus in membranes with aligned fibers display an elongated morphology following the alignment direction. As the culture time increased, higher cell viability is obtained on randomfibers for UC-MSCs while no differences are observed for NSCs. The membranes support neuronal differentiation of NSCs, as evidenced by markers for a neuronal filament protein (NF70) and for a microtubule-associated protein (MAP2).

8.
Braz J Microbiol ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874745

RESUMO

The objective of the study was to evaluate the frequency and genetic characteristics of ESBL-producing Escherichia coli and Klebsiella spp. and the risk factors associated with a high total bacterial count in bulk tank milk samples of dairy farms in three municipalities of the Antioquia Department, Colombia. Fifteen samples were positive for E. coli and Klebsiella spp. Subsequent analysis of the 16 S rRNA gene sequences confirmed these isolates included E. coli (n = 3), K. oxytoca (n = 11), and K. pneumoniae (n = 1). None of the isolates was positive for ESBL identification by phenotypic methods, but the only the isolate of K. pneumoniae was positive for the blaSHV61 gene by sequence analysis. The antibiotic susceptibility evaluation for all Klebsiella spp. isolates identified resistance to fosfomycin (50%; 6/12) and ampicillin (100%; 12/12). While most of the herds maintain adequate hygienic quality, specific risk factors such as having more than 60 milking cows, frequent changes in milkers, milking in paddocks, and using a chlorinated product for pre-dipping have been identified as associated with a high total bacterial count > 100,000 CFU/mL in bulk tank milk. However, certain variables including the milker being the owner of the animals and the proper washing and disinfection of the milking machine contribute to maintain a high level of hygiene and quality in the raw milk stored in the tanks. In conclusion, the frequency of ESBL producers was relatively low, with only K. pneumoniae testing positive for the blaSHV ESBL type. The presence of these bacteria in milk tanks represents a potential risk to public health for consumers of raw milk and its derivatives.

9.
Braz J Infect Dis ; 28(3): 103768, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38851212

RESUMO

We report an autochthonous case of mild unifocal chronic pulmonary paracoccidioidomycosis in a 48-year-old previously healthy woman with no history of possible environmental exposures in endemic rural areas, supposedly resulting from reactivation of a latent pulmonary focus secondary to the use of methotrexate for the control of Chikungunya arthropathy. Laboratory investigation ruled out other immunosuppression. Her only symptoms were a dry cough and chest pain. Diagnosis confirmed by needle lung biopsy. There were no abnormalities on physical examination nor evidence of central nervous system involvement. MRI of the total abdomen showed no involvement of other organs. Computed chest tomography showed a favorable evolution under the use of itraconazole (200 mg/day). Different tomographic presentations findings are highlighted when performed before and after treatment. CONCLUSIONS: PCM should be considered even in a woman without a history of consistent environmental exposure and in a non-endemic geographic area.


Assuntos
Pneumopatias Fúngicas , Metotrexato , Paracoccidioidomicose , Humanos , Feminino , Paracoccidioidomicose/tratamento farmacológico , Pessoa de Meia-Idade , Metotrexato/uso terapêutico , Metotrexato/efeitos adversos , Pneumopatias Fúngicas/tratamento farmacológico , Doença Crônica , Itraconazol/uso terapêutico , Tomografia Computadorizada por Raios X , Antifúngicos/uso terapêutico , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico
10.
Materials (Basel) ; 17(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38930318

RESUMO

Cancer is a major worldwide public health problem. Although there have already been astonishing advances in cancer diagnosis and treatment, the scientific community continues to make huge efforts to develop new methods to treat cancer. The main objective of this work is to prepare, using a green sol-gel method with coconut water powder (CWP), a new nanocomposite with a mixture of Gd3Fe5O12 and ZnFe2O4, which has never been synthesized previously. Therefore, we carried out a structural (DTA-TG and X-ray diffraction), morphological (SEM), and magnetic (VSM and hyperthermia) characterization of the prepared samples. The prepared nanocomposite denoted a saturation magnetization of 11.56 emu/g at room temperature with a ferromagnetic behavior and with a specific absorption rate (SAR) value of 0.5 ± 0.2 (W/g). Regarding cytotoxicity, for concentrations < 10 mg/mL, it does not appear to be toxic. Although the obtained results were interesting, the high particle size was identified as a problem for the use of this nanocomposite.

11.
Acta Ortop Bras ; 32(2): e278581, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38933358

RESUMO

Objective: Identify the predictors associated with delayed union at 6 months and non-union at 12 months in tibial shaft fractures treated with intramedullary nailing (IMN). Methods: This retrospective longitudinal study included a cohort of 218 patients who sustained tibial shaft fractures and received IMN between January 2015 and March 2022. We gathered data on a range of risk factors, including patient demographics, trauma intensity, associated injuries, fracture characteristics, soft tissue injuries, comorbidities, addictions, and treatment-specific factors. We employed logistic bivariate regression analysis to explore the factors predictive of delayed union and non-union. Results: At the 6-month follow-up, the incidence of delayed union was 28.9%. Predictors for delayed union included flap coverage, high-energy trauma, open fractures, the use of external fixation as a staged treatment, the percentage of cortical contact in simple type fractures, RUST score, and postoperative infection. After 12 months, the non-union rate was 15.6%. Conclusion: the main predictors for non-union after IMN of tibial shaft fractures are related to the trauma energy. Furthermore, the initial treatment involving external fixation and postoperative infection also correlated with non-union. Level of Evidence III; Retrospective Longitudinal Study.


Objetivo: identificar os fatores preditivos associados ao atraso de consolidação em 6 meses e à não união em 12 meses em fraturas da diáfise da tíbia tratadas com haste intramedular (HIM). Métodos: O estudo longitudinal retrospectivo de coorte incluiu 218 pacientes, que apresentaram fraturas da díafise da tíbia e receberam HIM entre janeiro de 2015 e março de 2022. Os desfechos principais pesquisados foram atraso de consolidação em 6 meses de acompanhamento, e não união em 12 meses. Coletou-se dados de uma variedade de fatores de risco. Utilizou-se análise de regressão logística bivariada para explorar os fatores preditivos de atraso de consolidação e não união. Resultados: Aos 6 meses, a incidência de atraso de consolidação foi de 28,9%. Os preditores de atraso de consolidação incluem cobertura de retalho, trauma de alta energia, fraturas expostas, uso de fixação externa como tratamento estagiado, porcentagem de contato cortical em fraturas simples, escore RUST e infecção pós-operatória. Após 12 meses, a taxa de não união foi de 15,6%, com fatores preditivos sendo necessidade de cobertura por retalho, lesão vascular, trauma de alta energia, fraturas expostas, uso de fixação externa como tratamento estagiado, porcentagem de contato cortical em fraturas simples e infecção pós-operatória. Nível de Evidência III; Estudo Longitudinal Retrospectivo.

12.
Acta Ortop Bras ; 32(2): e278586, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38933352

RESUMO

Objective: Assess complications and risks in staged femoral shaft fracture treatment using external fixation and intramedullary nailing (DCO). Methods: Analysis involved 37 patients with 40 fractures, mostly male (87.5%), average age 32.9 years. Data included ASA score, AO/OTA and Gustilo classifications, Glasgow Coma Score, Injury Severity Score, times to external fixation and conversion, ICU duration, nail type, and reaming status. Complications tracked were mortality, deep infection, and non-union. Results: Predominant fracture type was AO/OTA A (45%), with 40% open (Gustilo A, 93.8%). Average ISS was 21; GCS was 12.7. Median ICU stay was 3 days; average time to conversion was 10.2 days. Retrograde nails were used in 50% of cases, with reaming in 67.5%. Complications included deep infections in 5% and non-union in 2.5%. Conclusion: DCO strategy resulted in low infection and non-union rates, associated with lower GCS and longer ICU stays. Level of Evidence III; Retrospective Cohort Study.


Objetivo: Analisar taxa de complicações e riscos no tratamento estagiado de fraturas diafisárias do fêmur com fixador externo e conversão para haste intramedular (DCO). Métodos: Estudo com 37 pacientes, 35 masculinos, idade média de 32,9 anos, abordando escores ASA, classificação AO/OTA, Gustilo, Glasgow e ISS, tempo até a fixação externa, na UTI e tipo de haste. Complicações como mortalidade, infecção profunda e não união foram registradas. Resultados: Fraturas tipo AO/OTA A foram as mais comuns (45%), com 40% expostas (Gustilo A, 93,8%). ISS médio de 21 e ECG de 12,7. Média de 3 dias na UTI e 10,2 dias até a conversão. Uso de haste retrógrada em 50% dos casos e fresagem em 67,5%. As complicações incluíram infecção profunda em 5% e não união em 2,5%. A não união correlacionou-se com baixo ECG e tempo prolongado na UTI. Conclusão: A estratégia de DCO mostrou-se eficaz com baixas taxas de infecção e não união, associada a baixo ECG e tempo na UTI. Nível de Evidência III; Estudo de Coorte Retrospectivo.

13.
Biomacromolecules ; 25(6): 3384-3397, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38739855

RESUMO

This work cross-correlated rheological, thermodynamic, and conformational features of several natural polysaccharides to their cryoprotective performance. The basis of cryoprotection of FucoPol, pectin, and agar revealed a causal combination of (i) an emerging sol-gel transition (p = 0.014) at near-hypothermia (4 °C), (ii) noncolligative attenuated supercooling of the kinetic freezing point of water (p = 0.026) supporting ice growth anticipation, and (iii) increased conformational order (p < 0.0001), where helix-/sheet-like features boost cryoprotection. FucoPol, of highest cryoprotective performance, revealed a predominantly helical structure (α/ß = 1.5) capable of forming a gel state at 4 °C and the highest degree of supercooling attenuation (TH = 6.2 °C). Ice growth anticipation with gel-like polysaccharides suggests that the gel matrix neutralizes elastic deformations and lethal cell volumetric fluctuations during freezing, thus preventing the loss of homeostasis and increasing post-thaw viability. Ultimately, structured gels capable of attenuated supercooling enable cryoprotective action at the polymer-cell interface, in addition to polymer-ice interactions. This rationale potentiates implementing alternative, biobased, noncytotoxic polymers in cryobiology.


Assuntos
Sobrevivência Celular , Criopreservação , Crioprotetores , Polissacarídeos , Crioprotetores/química , Crioprotetores/farmacologia , Criopreservação/métodos , Polissacarídeos/química , Polissacarídeos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Gelo , Géis/química , Congelamento , Transição de Fase , Pectinas/química , Pectinas/farmacologia
14.
Int J Biochem Cell Biol ; 172: 106599, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38797495

RESUMO

Elevated levels of prostaglandin E2 have been implicated in the pathophysiology of various diseases. Anti-inflammatory drugs that act through the inhibition of cyclooxygenase enzymatic activity, thereby leading to the suppression of prostaglandin E2, are often associated with several side effects due to their non-specific inhibition of cyclooxygenase enzymes. Consequently, the targeted suppression of prostaglandin E2 production with innovative molecules and/or mechanisms emerges as a compelling therapeutic strategy for the treatment of inflammatory-related diseases. Therefore, in this study, a systematic analysis of 28 pyrazole derivatives was conducted to explore their potential mechanisms for reducing prostaglandin E2 levels. In this context, the evaluation of these derivatives extended to examining their capacity to reduce prostaglandin E2in vitro in human whole blood, inhibit cyclooxygenase-1 and cyclooxygenase-2 enzymes, modulate cyclooxygenase-2 expression, and suppress oxidative burst in human leukocytes. The results enabled the establishment of significant structure-activity relationships, elucidating key determinants for their activities. In particular, the 4-styryl group on the pyrazole moiety and the presence of chloro substitutions were identified as key determinants. Pyrazole 8 demonstrated the capacity to reduce prostaglandin E2 levels by downregulating cyclooxygenase-2 expression, and pyrazole-1,2,3-triazole 18 emerged as a dual-acting agent, inhibiting human leukocytes' oxidative burst and cyclooxygenase-2 activity. Furthermore, pyrazole 26 demonstrated effective reduction of prostaglandin E2 levels through selective cyclooxygenase-1 inhibition. These results underscore the multifaceted anti-inflammatory potential of pyrazoles, providing new insights into the substitutions and structural frameworks that are beneficial for the studied activity.


Assuntos
Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Dinoprostona , Leucócitos , Pirazóis , Explosão Respiratória , Humanos , Pirazóis/farmacologia , Pirazóis/química , Dinoprostona/metabolismo , Explosão Respiratória/efeitos dos fármacos , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Ciclo-Oxigenase 2/metabolismo , Ciclo-Oxigenase 1/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Relação Estrutura-Atividade , Inibidores de Ciclo-Oxigenase/farmacologia
15.
Int J Biol Macromol ; 271(Pt 1): 131981, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38811317

RESUMO

The development of new Drug Delivery Systems (DDS) by incorporating microparticles within hydrogels can prolong the release rate of drugs and/or other bioactive agents. In this study, we combined gellan gum/alginate microparticles within a thermoresponsive chitosan (Ch) hydrogel with ß-Glycerophosphate (ß-GP), designing the system to be in the sol state at 21 °C and in the gel state at 37 °C to enable the injectability of the system. The system was in the sol state between 10 °C and 21 °C. Higher concentrations of ß-GP (0, 2, 3, 4, 5 w/v%) and microparticles (0, 2 and 5 w/v%) allowed a faster sol-gel transition with higher mechanical strength at 37 °C. However, the sol-gel transition was not instantaneous. The release profile of methylene blue (MB) from the microparticles was significantly affected by their incorporation in Ch/ß-GP hydrogels, only allowing the release of 60-70 % of MB for 6 days, while the microparticles alone released all the MB in 48 h. The proposed system did not present cytotoxicity to VERO cell lines as a preliminary assay, with the Ch/ß-GP/GG:Alg having >90 % of cellular viability. The proposed Ch/ß-GP system proved to have a delaying effect on drug release and biocompatible properties, being a promising future DDS.


Assuntos
Alginatos , Quitosana , Glicerofosfatos , Polissacarídeos Bacterianos , Quitosana/química , Alginatos/química , Polissacarídeos Bacterianos/química , Glicerofosfatos/química , Animais , Chlorocebus aethiops , Hidrogéis/química , Células Vero , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Temperatura , Microesferas , Injeções , Sobrevivência Celular/efeitos dos fármacos
16.
Clin Obes ; 14(4): e12661, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38596856

RESUMO

Most patients with GNB1 encephalopathy have developmental delay and/or intellectual disability, brain anomalies and seizures. Recently, two cases with GNB1 encephalopathy caused by haploinsufficiency have been reported that also show a Prader-Willi-like phenotype of childhood hypotonia and severe obesity. Here we present three new cases from our expert centre for genetic obesity in which GNB1 truncating and splice variants, probably leading to haploinsufficiency, were identified. They all have obesity, hyperphagia and intellectual deficit. The clinical cases and their weight courses are presented, together with a review of all 68 published cases with GNB1 encephalopathy. Information on weight was not mentioned in most of these articles, so we contacted authors for additional clinical information on weight status and hyperphagia. Of the 42 patients whose weight status we could determine, obesity was present in 8 patients (19%). Obesity is significantly over-represented in the group with truncating and splicing variants. In this group, we see an obesity prevalence of 75%. Since GNB1 has been linked to several key genes in the hypothalamic leptin-melanocortin pathway, which regulates satiety and energy expenditure, our data support the potential association between GNB1 haploinsufficiency and genetic obesity. We also suggest GNB1 is a candidate gene for the known obesity phenotype of the 1p36 microdeletion syndrome given this chromosomal region includes the GNB1 gene. Knowledge of an additional obesity phenotype is important for prognosis, early interventions against obesity and awareness when prescribing weight-inducing medication.


Assuntos
Subunidades beta da Proteína de Ligação ao GTP , Haploinsuficiência , Obesidade , Humanos , Masculino , Feminino , Subunidades beta da Proteína de Ligação ao GTP/genética , Obesidade/genética , Criança , Deficiência Intelectual/genética , Pré-Escolar , Fenótipo , Adolescente , Hiperfagia/genética , Adulto
17.
Biomimetics (Basel) ; 9(4)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38667224

RESUMO

In recent decades, the requirements for implantable medical devices have increased, but the risks of implant rejection still exist. These issues are primarily associated with poor osseointegration, leading to biofilm formation on the implant surface. This study focuses on addressing these issues by developing a biomaterial for implant coatings. 45S5 bioglass® has been widely used in tissue engineering due to its ability to form a hydroxyapatite layer, ensuring a strong bond between the hard tissue and the bioglass. In this context, 45S5 bioglasses®, modified by the incorporation of different amounts of copper oxide, from 0 to 8 mol%, were synthesized by the melt-quenching technique. The incorporation of Cu ions did not show a significant change in the glass structure. Since the bioglass exhibited the capacity for being polarized, thereby promoting the osseointegration effectiveness, the electrical properties of the prepared samples were studied using the impedance spectroscopy method, in the frequency range of 102-106 Hz and temperature range of 200-400 K. The effects of CuO on charge transport mobility were investigated. Additionally, the bioactivity of the modified bioglasses was evaluated through immersion tests in simulated body fluid. The results revealed the initiation of a Ca-P-rich layer formation on the surface within 24 h, indicating the potential of the bioglasses to enhance the bone regeneration process.

18.
Environ Monit Assess ; 196(4): 368, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489071

RESUMO

This study analyzed the meteorological and hydrological droughts in a typical basin of the Brazilian semiarid region from 1994 to 2016. In recent decades, this region has faced prolonged and severe droughts, leading to marked reductions in agricultural productivity and significant challenges to food security and water availability. The datasets employed included a digital elevation model, land use and cover data, soil characteristics, climatic data (temperature, wind speed, solar radiation, humidity, and precipitation), runoff data, images from the MODIS/TERRA and AQUA sensors (MOD09A1 and MODY09A1 products), and soil water content. A variety of methods and products were used to study these droughts: the meteorological drought was analyzed using the Standardized Precipitation Index (SPI) derived from observed precipitation data, while the hydrological drought was assessed using the Standardized Soil Index (SSI), the Nonparametric Multivariate Standardized Drought Index (NMSDI), and the Parametric Multivariate Standardized Drought Index (PMSDI). These indices were determined using water balance components, including streamflow and soil water content, from the Soil Water Assessment Tool (SWAT) model, and evapotranspiration data from the Surface Energy Balance Algorithm for Land (SEBAL). The findings indicate that the methodology effectively identified variations in water dynamics and drought periods in a headwater basin within Brazil's semiarid region, suggesting potential applicability in other semiarid areas. This study provides essential insights for water resource management and resilience building in the face of adverse climatic events, offering a valuable guide for decision-making processes.


Assuntos
Secas , Monitoramento Ambiental , Brasil , Água , Solo
20.
Biomimetics (Basel) ; 9(3)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38534828

RESUMO

Open-cell foams based on hydroxyapatite (HAp) can mimic the extracellular matrix (ECM) to better replace damaged hard tissues and assist in their regeneration processes. Aerogels of HAp nanowires (NW) with barium titanate (BT) particles were produced and characterized regarding their physical and chemical properties, bioactivity, and in vitro cytotoxicity. Considering the role of piezoelectricity (mainly due to collagen) and surface charges in bone remodeling, all BT particles, of size 280 nm and 2 and 3 µm, contained BaTiO3 in their piezoelectric tetragonal phase. The synthesized nanowires were verified to be AB-type carbonated hydroxyapatite. The aerogels showed high porosity and relatively homogeneous distribution of the BT particles. Barium titanate proved to be non-cytotoxic while all the aerogels produced were cytotoxic for an extract concentration of 1 mg/mL but became non-cytotoxic at concentrations of 0.5 mg/mL and below. It is possible that these results were affected by the higher surface area and quicker dissolution rate of the aerogels. In the bioactivity assays, SEM/EDS, it was not easy to differentiate between the apatite deposition and the surface of the HAp wires. However, a quantitative EDS analysis shows a possible CaP deposition/dissolution cycle taking place.

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