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1.
Clin Toxicol (Phila) ; : 1-2, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225236

RESUMO

INTRODUCTION: Computed tomography can be used to screen and diagnose the presence of drug-filled packets in the body. We present an unusual computed tomography finding in a suspected body packer. CASE SUMMARY: A traveller suspected of being a body packer was brought to the emergency department complaining of low back pain. On examination, there was an abdominal cast circumferentially encasing his abdomen, which he alleged was part of the management of his lower back pain in his own country. IMAGES: A plain computed tomogram of the abdomen and pelvis revealed that the cast was made of materials with a nodular appearance and heterogeneous density, which was different from that of a plaster of Paris cast. An investigation later confirmed the cast contained cocaine. CONCLUSION: Our case demonstrates how a body packer can traffic drugs outside their body for an alleged medical reason.

2.
Int J Biol Macromol ; 279(Pt 2): 135239, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39218175

RESUMO

There are lots of gene editing tools for targeting genome sequences. Some are almost known, and most are a complete mystery and undiscovered. CRISPR/Cas editing tools have brought about a major revolution in medicine. Researchers have shown that CRISPR can modify DNA much more accurately, economically and easily than previous methods. CRISPR has proven itself effective for the deletion, replacement and insertion of DNA fragments into cell types, tissues and organisms. Recently, combining CRISPR/Cas with factors (transcription factors/repressors, exonucleases, endonucleases, transposons, caspase, fluorescent proteins, oxidoreductive enzymes, DNA/RNA polymerases), and elements (aptamers, barcodes, fluorescent probes, Trigger) have provided genome, transcriptome, proteome and epigenome modification. These modules are being investigated for cancer prevention and therapy and this review focuses on such innovative combinations that hopefully will become a clinical reality in the near future.

3.
Sci Rep ; 14(1): 21052, 2024 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251716

RESUMO

A meta-analysis including all relevant randomized controlled trials was conducted to compare soft bandage, splint and cast as the treatment of torus fracture. PubMed, Scopus, and Web of Science databases were searched in January 2023. Two comparisons were made: (1) splint versus cast, and (2) bandage versus rigid immobilization (i.e. splint or cast). Main outcomes were pain, clinical healing of the fracture and return to activities. Secondary outcomes were adverse events (skin issues, problems with cast/splint/bandage) and patient/parental satisfaction. Seven studies with 1550 patients were included. Splint was associated with higher pain scores at 3 days compared to cast (Mean difference [MD] 1.00, CI 0.06-1.94) and at 1 week (MD 1.46, CI 0.84-2.08, moderate-certainty evidence), but faster return to activities (at 3 weeks RR 1.77, CI 1.09-2.88, at 4 weeks RR 1.44, CI 1.11-1.82, moderate-certainty evidence). All torus fractures heal clinically within 3-4 weeks (low-certainty evidence). Bandage may lead to slightly higher pain score (MD 0.35, CI 0.04-0.66, moderate-certainty evidence) at first day after treatment compared to rigid immobilization, but no evidence of a difference was found in later time points. In conclusion, soft bandage or removable wrist splint seem to be optimal first-line treatment of distal forearm torus fracture.


Assuntos
Bandagens , Moldes Cirúrgicos , Contenções , Humanos , Criança , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto , Traumatismos do Antebraço/terapia
4.
Cureus ; 16(8): e66696, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39262549

RESUMO

Distal radius fractures are among the most common pediatric injuries, affecting thousands of children each year. These fractures often require clinical intervention to reduce displacement and ensure the proper healing of the growth plate and wrist bone. The primary objective of this comprehensive analysis is to compare the effectiveness of open reduction and internal fixation (ORIF) versus cast placement in the treatment of pediatric distal radius fractures, with the aim of identifying the optimal treatment approach. Therefore, a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted on pediatric distal radius displacement fractures using extensive database searches from 2000 to 2024 for specific keywords, ensuring transparency and reproducibility. Our findings indicate that higher displacement necessitates ORIF to minimize long-term complications and ensure better functional outcomes for pediatric patients. Rare studies comparing ORIF and cast placement are analyzed, emphasizing the advantages and limitations of each approach. The document concludes that the choice between ORIF and casting depends on factors such as fracture severity, patient's age, and specific characteristics of the injury to ensure optimal outcomes in pediatric distal radius fracture management. In conclusion, our data suggests that ORIF and cast placement each have pros and cons for pediatric distal radius fractures, with the best treatment depending on fracture specifics and patient factors, but neither method is clearly superior for long-term outcomes.

5.
Cureus ; 16(8): e66794, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39268282

RESUMO

Introduction We aimed to evaluate orthotic hygiene, preference for immobilization material, and frequency of unplanned orthotic adjustments and replacements. Methods All patients with fiberglass casts, thermoplastic splints, or prefabricated braces who presented at a large private academic institution between January 2020 and July 2023 were provided an 11-item survey assessing the length of immobilization, frequency of orthotic changes, orthotic hygiene, preference of immobilization, and whether patients recall instructions regarding orthotic care. Results A total of 385 surveys were collected, consisting of 96 (24.9%) casts, 202 (52.5%) thermoplastic splints, and 87 (22.6%) prefabricated braces. Patients were most frequently immobilized for two to six weeks. Of those, 106 (27.5%) patients required an unplanned adjustment or replacement. Almost half (182 patients, 47.3%) attempted to clean their orthotics, which was significantly greater among thermoplastic splints. A total of 229 (59.5%) respondents reported either not receiving or were unsure if they received instruction on proper orthotic hygiene. Conclusion Orthotic care and hygiene instructions are often overlooked or not retained by patients. Nearly one-third of patients required an unplanned adjustment or replacement, which was most frequent with thermoplastic orthotics.

6.
Angle Orthod ; 94(4): 400-407, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39229947

RESUMO

OBJECTIVES: To evaluate leveling of the Curve of Wilson (COW) by two different treatment appliances (clear aligners [CA] and continuous archwire fixed appliances [FA]) in a permanent dentition sample of patients. MATERIALS AND METHODS: Digital casts of 40 patients (CA group = 20 patients; FA group = 20 patients) were collected. Angular values for COW, right and left vertical height difference of lower first molars, and linear distance between lower teeth and the WALA ridge were analyzed for pre- (T1), posttreatment (T2) and on final virtual (ClinCheck) models (T2-CC) of the CA group. An unpaired t-test was used to evaluate significant intergroup differences (P < .05), while a paired t-test was used for posttreatment CA intragroup comparison. RESULTS: FA group showed better control of second molar crown positions compared to CA group (47-WALA = -0.2 ± 0.1 mm, 37-WALA = -0.6 ± 0.3 mm). No significant difference was detected for linear distance of lower first molars and the WALA ridge or for vertical height difference. CA group showed a greater reduction of distance between lower premolars and the WALA ridge (mean difference: -0.5 mm for both 45-WALA and 35-WALA; mean difference: -0.5 mm for 44-WALA, -0.6 mm for 34-WALA). Predictability for the CA group was high for every measurement (87% Right COW, 89% Left COW, 88% 46 Vertical Diff, 87% 36 Vertical Diff). CONCLUSIONS: Clear aligner and continuous archwire mechanics were effective in leveling COW. FA was more effective in changing crown position of lower second molars with respect to the WALA ridge, while CA provided a greater distance reduction between lower premolars and WALA ridges compared to FA.


Assuntos
Dente Molar , Fios Ortodônticos , Técnicas de Movimentação Dentária , Humanos , Estudos Retrospectivos , Feminino , Masculino , Técnicas de Movimentação Dentária/instrumentação , Técnicas de Movimentação Dentária/métodos , Dentição Permanente , Adolescente , Desenho de Aparelho Ortodôntico , Aparelhos Ortodônticos Fixos , Modelos Dentários
7.
Materials (Basel) ; 17(17)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39274569

RESUMO

Laser beam remelting is a relatively simple and highly effective technique for the physical modification of surfaces to improve resistance to cavitation erosion. In this study, we investigated the effect of laser remelting on the surface of cast stainless steel with 0.40% C, 25% Cr, 20% Ni, and 1.5% Si on cavitation erosion behavior in tap water. The investigation was conducted using a piezoceramic crystal vibrator apparatus. Base laser beam parameters were carefully selected to result in a defect-free surface (no porosity, material burn, cracks) with hardness capable of generating better resistance to cavitation erosion. The experimental results were compared with those of the reference material. Surface morphology and microstructure evolution after cavitation tests were analyzed using an optical metallographic microscope (OM), scanning electron microscope (SEM), and hardness tests to explore the mechanism of improving surface degradation resistance. The conducted research demonstrated that surfaces modified by laser remelting exhibit a 4.8-5.1 times greater increase in cavitation erosion resistance due to the homogenization of chemical composition and refinement of the microstructure, while maintaining the properties of the base material.

8.
Materials (Basel) ; 17(17)2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39274656

RESUMO

Tensile and low-cycle fatigue tests of high-strength compacted graphite cast iron (CGI, RuT450) were carried out at 25 °C, 400 °C, and 500 °C, respectively. The results show that with the increase in temperature, the tensile strength decreases slowly and then decreases rapidly. The fatigue life decreases, and the life reduction increases at high temperature and high strain amplitude. The oxide layer appears around the graphite and cracks at high temperature, and the dependence of crack propagation on ferrite gradually decreases. With the increase in strain amplitude, the initial cyclic stress of compacted graphite cast iron increases at three temperatures, and the cyclic hardening phenomenon is obvious. The fatigue life prediction method based on the energy method and damage mechanism for compacted graphite cast iron is summarized and proposed after comparing and analyzing a large amount of fatigue data.

9.
Materials (Basel) ; 17(17)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39274664

RESUMO

A precise Johnson-Cook (J-C) constitutive model is the foundation for precise calculation of finite-element simulation. In order to obtain the J-C constitutive model accurately for a new cast and forged alloy GH4198, an inverse identification of J-C constitutive model was proposed based on a genetic-particle swarm algorithm. Firstly, a quasi-static tensile test at different strain rates was conducted to determine the initial yield strength A, strain hardening coefficient B, and work hardening exponent n for the material's J-C model. Secondly, a new method for orthogonal cutting model was constructed based on the unequal division shear theory and considering the influence of tool edge radius. In order to obtain the strain-rate strengthening coefficient C and thermal softening coefficient m, an orthogonal cutting experiment was conducted. Finally, in order to validate the precision of the constitutive model, an orthogonal cutting thermo-mechanical coupling simulation model was established. Meanwhile, the sensitivity of J-C constitutive model parameters on simulation results was analyzed. The results indicate that the parameter m significantly affects chip morphology, and that the parameter C has a notable impact on the cutting force. This study addressed the issue of missing constitutive parameters for GH4198 and provided a theoretical reference for the optimization and identification of constitutive models for other aerospace materials.

10.
Materials (Basel) ; 17(17)2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39274722

RESUMO

Processing of cast-iron castings by machining is associated with a large amount of post-production waste in the form of cast-iron chips, which constitute up to about 5% of the weight of the entire casting. In the case of serial production, this generates large amounts of post-production waste, constituting a constantly growing scale of environmental problems. The aim of this research was to develop a simple and cheap method of utilizing post-production waste of gray cast-iron chips from the machining process for the production of small structural elements of water supply fittings. The analysis of the state of knowledge indicates that the simplest method of managing waste chips is to use them as a starting material in the process of manufacturing polymer composites. The most frequently chosen material for the matrix of polymer composites reinforced with metal powders is epoxy resin. The epoxy composite was produced by the vacuum-assisted casting method. This paper presents the results of tests of morphological, mechanical, and corrosion properties of epoxy composites filled with grey cast-iron powder with a grain size below 0.075 mm and a mass content in the composite of 65%. The composite cured at 130 °C for 90 min had the best mechanical properties. The sample cured at 130 °C for 90 min was observed to have the optimum effect, with a tensile strength of 28.35 MPa, a flexural strength of 55.4 MPa, and a compressive strength of 53.8 MPa. All tested composites were characterized by very good thermal resistance and, in comparison to gray cast iron, over 2.5 times lower weight and an over three times lower corrosion rate in the tap water environment.

11.
Materials (Basel) ; 17(17)2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39274765

RESUMO

The hydration heat generated during the concreting of cast-in-place piles causes thermal disturbance to the surrounding permafrost, leading to its thawing. This further affects the stability of the pile foundation and degrades the construction progress. To explore the influence mechanisms of the concrete hydration heat on the permafrost temperature field around the pile, as well as that of different construction seasons on the pile-side boundary conditions and permafrost temperature field, monitoring results of on-site tests and numerical simulation were used to analyze the distribution law of the pile soil temperature field in space and time, and the pile-side boundary conditions and permafrost temperature field during construction seasons. The results show that the temperature trend of the pile foundation can be divided into three stages: a rapid rise phase (0∼2 d), a rapid decline phase (2∼10 d), and a slow decline and stabilization phase (10∼90 d). As the radial distance from the pile center decreases, there occur a corresponding acceleration in temperature increase and an elevated maximum temperature rise (MTR). The influence range of the molding temperature and the hydration heat is about 1∼2 times the pile diameter and less than 1.5 m in the depth direction. Compared to the atmospheric temperature, there is a lag in the change in the permafrost temperature caused by accumulation of ground temperature, and the significant difference between the two leads to an increased rate of heat exchange at the boundary condition. Conducting drilling operation and cast-in-place pile construction in the cold seasons is conducive to reducing the thermal disturbance to the permafrost around the pile in permafrost areas.

12.
Eur J Med Res ; 29(1): 410, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39118170

RESUMO

Superior mesenteric artery syndrome (SMAS) is a rare and unpredictable complication after correction spine surgery for adolescent idiopathic scoliosis (AIS). The management of this condition is poorly investigated, with controversial outcomes. This investigation systematically reviewed current evidence on pathogenesis, risk factors, management, and outcomes of SMAS following correction spine surgery for AIS. The present systematic review was conducted according to the 2020 PRISMA statement. All the included investigations reported SMAS presentation following scoliosis correction surgery in AIS. 29 articles with 61 eligible patients were included in this review. The mean age of the patients was 15.8 ± 7.2 years. The mean weight was 45.3 ± 8.0 kg, the mean height 159.6 ± 13.6 cm, and the mean BMI 16.5 ± 2.9 kg/m2. The mean duration of the treatment for SMAS was 21.6 ± 10.3 days. The mean interval between spine surgery and symptoms of SAMS was 69 days, with high between-studies variability (3 days to 4 years). Prompt identification of risk factors and an early diagnosis are necessary to manage SMAS and reduce the risk of complications. Additional investigations are required to establish risk factors and diagnostic criteria.Level of evidence Level IV, systematic review.


Assuntos
Escoliose , Síndrome da Artéria Mesentérica Superior , Humanos , Escoliose/cirurgia , Síndrome da Artéria Mesentérica Superior/etiologia , Adolescente , Complicações Pós-Operatórias/etiologia , Fatores de Risco
13.
Chemosphere ; 364: 143007, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39098347

RESUMO

High-level radioactive waste needs to be safely stored for a long time in a deep geological repository by using a multi-barrier system. In this system, suitable barrier materials are selected that ideally show long-term stability to prevent early radionuclide release into the biosphere. In this study, different container matals (copper and cast iron) and pore water compositions (Opalinus Clay pore water and saline cap rock solution) were combined with Bavarian bentonite in static batch experiments to investigate microbial-influenced corrosion. The increasing concentration of iron and copper in the solution as well as detected corrosion products on the metal surface are indicative of anaerobic corrosion of the respective metals during an incubation of 400 days at 37 °C. However, although the intrinsic microbial bentonite community was stimulated with either lactate or H2, an acceleration of cast iron- and copper corrosion did not occur. Furthermore, neither corrosive bacteria nor conventional bacterial corrosion products, such as metal sulfides, were detected in any of the analyzed samples. The analyses of geochemical parameters (e.g. ferrous iron-, iron-, copper- and potassium concentrations as well as redox potentials) showed significant changes in some cast iron- and copper-containing setups, but these changes did not correlate with the microbial community structure in the respective microcosms, as confirmed by statistical analyses. Hence, the analyzed Bavarian bentonite (type B25) showed no significant contribution to cast iron and copper corrosion under the applied conditions after 400 days of incubation. From this perspective, bentonite B25 could be a suitable candidate as a geotechnical barrier in future repositories.

14.
Cureus ; 16(7): e64214, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39130933

RESUMO

Pigment-induced acute kidney injury (AKI) is an important and preventable complication of rhabdomyolysis or hemolysis. It is characterized by the release of free heme pigment (myoglobin or hemoglobin) in the circulation, leading to direct injury of the proximal tubule and distal tubule obstruction by pigment cast. We are reporting eight cases of pigment-induced AKI, including six cases of myoglobin cast nephropathy and two cases of hemoglobin cast nephropathy. The causes of rhabdomyolysis were strenuous exercise, infection/febrile illness, and drug-induced neuroleptic malignant syndrome. Paroxysmal nocturnal hemoglobinuria and anti-tuberculosis treatment (rifampicin and isoniazid) had led to hemoglobin cast nephropathy each in one case. Seven cases had severe renal failure requiring dialysis. Short-term renal outcome was favorable. However, long-term follow-up is necessary to determine whether pigment-induced AKI has delayed sequelae. Therefore, clinicians should consider rhabdomyolysis or hemolysis as potential hidden causes of AKI in diverse clinical conditions, especially those of non-traumatic origin, to achieve an accurate diagnosis.

15.
Materials (Basel) ; 17(15)2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39124406

RESUMO

In this paper, enhancing the tribological characteristics of novel cast metallic materials-hybrid multi-component cast irons-by applying a strengthening heat treatment is described. The experimental materials were the cast alloys of a nominal composition (5 wt.% W, 5 wt.% Mo, 5 wt.% V, 10 wt.% Cr, 2.5 wt.% Ti, Fe is a balance) supplemented with 0.3-1.1 wt.% C and 1.5-2.5 wt.% B (total of nine alloys). The heat treatment was oil-quenching followed by 200 °C tempering. The quench temperature (QT) varied in the range of 900-1200 °C, with a step of 50 °C (with a 2-h holding at QT). The correlation of the QT with microstructure and properties was estimated using microstructure/worn surface characterization, differential scanning calorimetry, hardness measurement, and three-body-abrasive wear testing (using Al2O3 particles). The as-cast alloys had a multi-phase structure consisting of primary and/or eutectic borocarbide M2(B,C)5, carboborides M(C,B), M7(C,B)3, M3(C,B), and the matrix (ferrite, martensite, pearlite/bainite) in different combinations and volume fractions. Generally, the increase in the quenching temperature resulted in a gradual increase in hardness (maximally to 66-67 HRC) and a decrease in the wear rate in most alloys. This was due to the change in the phase-structure state of the alloys under quenching, namely, the secondary carboboride precipitation, and replacing ferrite and pearlite/bainite with martensite. The wear rate was found to be inversely proportional to bulk hardness. The maximum wear resistance was attributed to QT = 1150-1200 °C, when the wear rate of the alloys was lowered by three to six times as compared to the as-cast state. With the QT increase, the difference in the wear rate of the alloys decreased by three times. The highest abrasive resistance was attributed to the alloys with 1.1 wt.% C, which had a 2.36-3.20 times lower wear rate as compared with that of the reference alloy (13 wt.% Cr cast iron, hardness of 66 HRC). The effects of carbon and boron on hardness and wear behavior are analyzed using the regression models developed according to the factorial design procedure. The wear mechanisms are discussed based on worn surface characterization.

16.
Foot Ankle Int ; : 10711007241268147, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39188121

RESUMO

BACKGROUND: Charcot neuroosteoarthropathy (CNO) is characterized with increased osteoclastic activity that can be curbed with antiresorptive agents. Chronic kidney disease (CKD) precludes bisphosphonates but anti-receptor activator of nuclear factor-B ligand (anti-RANKL) antibody, denosumab, can be contemplated in CKD. We investigated denosumab for active CNO of foot in CKD for CNO remission. METHODS: During the study period, 446 persons of diabetes with unilateral, active CNO of foot and CKD were identified and 78 were finally enrolled. Patients received either 60 mg denosumab (single-dose, subcutaneous) along with standard of care (SoC) as total contact cast (TCC) (group A; n = 26) or SoC (group B; n = 52) only. Patients were followed every 4 weeks until CNO remission and subsequently every 8 weeks until 48 weeks following remission. Remission was defined as temperature difference <2 °C between 2 feet confirmed twice (4 weeks apart) with clinical resolution of signs of inflammation. The primary outcome studied was proportion of patients achieving remission within 48 weeks and the time to remission. RESULTS: Median age was 56.5 (48.8-65) and 57 (48.5-61.2) years, P = .57; duration of diabetes 16 (10-25.3) and 14.9 (10-19) years, P = .151; and estimated glomerular filtration rate 44.8 (21.1-65.6) and 45.7 (32.9-55.7) mL/min/1.73 m2, P = .771, in group A and B, respectively. Median temperature difference at presentation between the affected and opposite foot was 3.4 °C (2.7-6.9) and 3.2 °C (2.2-4.0), P = .119, respectively. All patients achieved remission in group A (100%) compared with 42 (80.8%) in group B (P = .006) (hazard ratio 0.52, 95% CI: 0.32-0.87; P = .012). The median time to remission was similar in the 2 groups (15 [11-25] and 17.5 [14-31.5] weeks, P = .229, respectively). 25-Hydroxyvitamin D3 >14 ng/mL was significantly associated (OR 9.5, 95% CI 1.04-87.5, P = .045) with remission. CONCLUSION: Anti-RANKL antibody added to SoC (TCC) induces remission of active foot CNO in greater proportions of patients with diabetes and CKD.

17.
Materials (Basel) ; 17(16)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39203211

RESUMO

This article deals with the possibility of using 3D-printed models as an input for the production of a mould for cast iron castings. This new progressive process is significantly faster (with sufficient accuracy) compared to the current way of making models for moulds. The need to create a wooden model is removed by this process. The quality of this wooden model was highly dependent on the experience and qualifications of the worker. This article describes the manufacturing process of the model and mould in detail. The key dimensions of the final parts are compared with the model and, thus, the accuracy of the chosen procedure is verified. A 3D-printing technology known as Multi Jet Fusion (MJF) was used to produce the model. The material used for the production of the model is polyamide PA12 with 40% glass fibre filling. This material has sufficient structural and strength properties to be used for the given application. Taking into account the dimensions of the part and the printing space of the printer, it was necessary to structurally modify and divide the part. The inlet cone of a turbine is used as an example This cone is produced from grey cast iron as standard.

18.
Materials (Basel) ; 17(16)2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39203318

RESUMO

The effects of the rare earth element La on the microstructure and mechanical properties of cast Al-5.4Cu-0.7Mg-0.6Ag alloys have been investigated through metallographic observation, scanning electron microscopy analysis, transmission electron microscopy, X-ray diffraction, and tensile testing. The present form and action mechanism of La have been analyzed. The findings indicate that the inclusion of trace amounts of La markedly diminishes the grain size in the Al-Cu-Mg-Ag alloy. Furthermore, as the La content increases, the alloy's strength is significantly improved. When the La concentration reaches 0.4 wt.%, the mechanical properties of the alloy, both at room temperature and at 350 °C, surpass those of the alloy lacking rare earth elements. When the added rare earth La content exceeds 0.2 wt.%, the emergence of the Al6Cu6La phase causes the alloy structure to exhibit a skeletal morphology, altering the morphology and distribution of excess second phases along grain boundaries, thereby impacting the alloy's overall performance. Incorporating La leads to a reduction in the size of the strengthening precipitate phase Ω while also enhancing its precipitation density, but an excess of La leads to the emergence of Al6Cu6La, depleting the available Cu and suppressing the precipitation of the Ω phase, ultimately affecting the mechanical properties of the alloy.

19.
Biochem Biophys Res Commun ; 733: 150606, 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39208645

RESUMO

Age-related morbidity has become an increasingly significant issue worldwide. Sarcopenia, the decline in skeletal muscle mass and strength with age, has been reported to be a risk factor for cognitive impairment. Our previous study revealed that skeletal muscle atrophy shifts the onset of memory dysfunction earlier in young Alzheimer's disease mice and found that hemopexin is a myokine responsible for memory loss. This study aimed to elucidate the occurrence of memory impairment due to skeletal muscle atrophy in non-genetically engineered healthy young mice and the involvement of hemopexin. Closed-colony ddY mice at 12-13 weeks of age were used. Both hind limbs were immobilized by cast attachment for 14 d. Casting for 2 weeks induced a loss of skeletal muscle weight. The memory function of the mice was evaluated using a novel object recognition test. The cast-attached mice exhibited memory impairment. Hemopexin levels in the conditioned medium of the skeletal muscle, plasma, and hippocampus were increased in cast-attached mice. Continuous intracerebroventricular hemopexin infusion induced memory deficits in non-cast mice. To investigate whether hemopexin is the main causative factor of cognitive impairment, cast-attached mice were intracerebroventricularly infused with an anti-hemopexin antibody. Cast-induced memory impairment was reversed by the infusion of an anti-hemopexin antibody. These findings provide new evidence that skeletal muscle atrophy causes memory impairment in healthy young mice through the action of hemopexin in the brain.

20.
Int Orthod ; 22(4): 100903, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39181038

RESUMO

PURPOSES: The aim of this study was to examine the effects of post material type and the presence of ferrules on the torque and intrusion load of the upper central tooth using finite element analysis. METHODS: The upper central tooth and surrounding tissues (cortical bone, cancellous bone, and periodontal ligament) were modelled in three dimensions using the Spaceclaim software. Five simulated models (SM) different modifications were made to this main model: metal cast post (SM1) and glass fiber post-core with zirconium crown and without a ferrule (SM2), metal cast (SM3) post and glass fiber post with a ferrule and zirconium crown (SM4) and only zirconium crown (SM5). In all five simulations, in order to simulate lingual root torque movement, a total load of 40 grams was applied to the bracket slot as 20 grams of force couples and in order to simulate intrusion movement, a load of 40 grams was applied to the superior wall of the bracket slot. The stress caused by the applied loads on the root surfaces was determined using finite element analysis. Maximum principal stress (MPS) value was used in the comparison. RESULTS: The highest root surface MPS values for both intrusion and torque loads belonged to SM2 (3.864 and 0.379MPa, respectively). The presence of ferrules in both intrusion and torque loads reduced the stress by approximately half (from 3.864 to 2.004MPa). In all five models, the radicular area with higher stress was located in the cervical third on the lingual surface when both torque and intrusion loads were applied. CONCLUSION: The amount and localization of stress was affected by the type of post material. The variation in stress values between the materials remains within a safe range (0.099 and 3.87MPa), making both materials suitable for use under orthodontic forces.

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