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1.
Cell Tissue Res ; 395(2): 211-220, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38112806

RESUMO

Peripheral artery disease (PAD) affects more than 230 million people worldwide, with approximately 11% of patients presenting with advanced-stage PAD or critical limb ischemia (CLI). To avoid or delay amputation, particularly in no-option CLI patients with infeasible or ineffective revascularization, new treatment strategies such as regenerative therapies should be developed. Mesenchymal stem cells (MSCs) are the most popular cell source in regenerative therapies. They possess significant characteristics such as angiogenic, anti-inflammatory, and immunomodulatory activities, which encourage their application in different diseases. This phase I clinical trial reports the safety, feasibility, and probable efficacy of the intramuscular administration of allogeneic Wharton's jelly-derived MSCs (WJ-MSCs) in type 2 diabetes patients with CLI. Out of six screened patients with CLI, five patients were administered WJ-MSCs into the gastrocnemius, soleus, and the proximal part of the tibialis anterior muscles of the ischemic lower limb. The safety of WJ-MSCs injection was considered a primary outcome. Secondary endpoints included wound healing, the presence of pulse at the disease site, the absence of amputation, and improvement in visual analogue scale (VAS), pain-free walking time, and foot and ankle disability index (FADI). No patient experienced adverse events and foot or even toe amputation during the 6-month follow-up. Six months after the intervention, there were a significantly lower VAS score and significantly higher pain-free walking time and FADI score than the baseline, but no statistically significant difference was seen between other time points. In conclusion, allogeneic WJ-MSC transplantation in patients with CLI seems to be safe and effective.


Assuntos
Diabetes Mellitus Tipo 2 , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Geleia de Wharton , Humanos , Isquemia Crônica Crítica de Membro , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Células-Tronco Mesenquimais/metabolismo , Diferenciação Celular
2.
Sci Total Environ ; 872: 161996, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36775166

RESUMO

Toxic elements released due to mining activities are of the most important environmental concerns, characterised not only by their concentration, but also by their distribution among different chemical species, known as speciation. These are conventionally determined using chemical analysis and sequential extraction, which are expensive and time-demanding. In this study, the possibility of using visible-near-infrared-shortwave infrared (VNIR-SWIR) reflectance spectroscopy was investigated as an alternative technique to quantify the contents of cobalt (Co) and nickel (Ni) in soil samples collected from Sarcheshmeh copper mine waste dump surface, in Iran. As a novel approach, the capability of VNIR-SWIR spectroscopy was also investigated in speciation of those elements. Three machine learning (ML) techniques (i.e., extreme gradient boosting (EGB), random forest (RF) and support vector regression (SVR)) were used to make relationships between soil spectral responses and Co and Ni contents of the samples. For all ML algorithms, the best prediction accuracies were obtained by the models developed on the first derivative (FD) spectra (for Co: RMSEp values of 7.82, 8.03 and 9.22 mg·kg-1, and for Ni: RMSEp values of 9.88, 10.32 and 11.02 mg·kg-1, using EGB, RF and SVR, respectively). Spatial variability maps of elements showed relatively similar patterns between observed and predicted values. Correlation and ML (EGB, RF, SVR)-based methods revealed that the most important wavelengths for Co and Ni prediction were those related to iron oxides/hydroxides and clay minerals, as two main soil properties responsible for controlling their speciation. This study demonstrated that the EGB technique was successful at indirect quantification and spatial variability mapping of Co and Ni on the mine waste dump surface. In addition, it provided an inspiration for implementation of the VNIR-SWIR reflectance spectroscopy as a potentially fast and cost-effective method for speciation studies of toxic elements, especially in heterogeneous soil environments.

3.
Comput Ind Eng ; 176: 108933, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36594043

RESUMO

Covid-19 virus (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) threatens the health of human beings worldwide, imposing a concern for the world and prompting governments to control the contagion. Although vaccination is a proper tool to control the transmission, the efficient allocation of limited health-care resources to massive patients can improve the effectiveness of medical services. Relying on the Artificial Neural Network (ANN), the aim of this research is to enhance the future efficiency of Covid-19 treatment centers by forecasting their efficiency and providing benchmarks. To do this, we use the congestion approach of data envelopment analysis (DEA) based on the theory of economies of scale principles. In the traditional input-oriented DEA, inefficient decision-making units (DMUs) can become efficient merely by reducing the inputs. However, this may not always be true in real-world applications such as improving the efficiency of COVID-19 treatment centers (DMUs). Meaning that the treatment centers with less congested inputs (e.g., ventilators, test equipment, pulmonologists, and nurses, etc.) normally have higher mortality rates. For this reason, in this study, we take the congested inputs approach into account to provide proper benchmarks for the inefficient treatment centers. According to the congestion approach of DEA, an optimum increase in congested inputs can lead to a greater than a proportional increment in outputs. In other words, if more respiratory equipment, pulmonologists, patient rooms, nurses and beds, etc. are allocated to Covid-19 treatment centers, not only the number of deaths (undesirable outputs) are decreased, but also the number of recoveries (desirable outputs) are increased. Such an optimal rise in the congested inputs is determined in pairwise comparisons derived from the model. Accordingly, in this study, first, considering the congestion approach of DEA and historical data of five periods, we identify the initial efficiency of Iranian Covid-19 treatment centers. Then, by running ANN, we forecast the future inputs and outputs, the overall efficiency, and rank of the treatment centers. By doing this, the prospective efficient and inefficient DMUs are identified, and appropriate benchmarks are determined.

4.
Clin Case Rep ; 10(9): e6309, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36177073

RESUMO

Intussusception is a condition in which a segment of the gastrointestinal tract invaginates into the lumen of another segment. Adult intussusception is less common than juvenile intussusception in terms of cause, appearance, and treatment. Because the clinical picture can be quite atypical and difficult to interpret, it is frequently misdiagnosed at first. Herein, we report the case of a previously healthy 23-year-old female patient who presented to the Emergency Department (ED) with acute abdominal pain, vomiting, and diarrhea for 1 day following her last menstrual period. Ileocecal intussusception was discovered throughout the investigation. She was rushed for open abdominal surgery. Meckel's diverticulum was found as a pathologic lead point in the resected specimen, with no evidence of malignancy. Although intussusception is rare in adults, it should be considered in patients who have nonspecific stomach pain.

5.
BMC Surg ; 20(1): 220, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33008424

RESUMO

BACKGROUND: Splenic rupture is an emergency condition and a vast number of cases are secondary to trauma. Several underlying pathologies have also been associated with splenic rupture, such as hematological diseases, malignancies, and infectious and inflammatory diseases. CASE PRESENTATION: The patient was a 52-year-old man who referred to the Poursina Hospital in Rasht while complaining of abdominal pain from the day before hospitalization. The patient reported a history of lethargy, fever, and nausea. In the examinations performed, there was a brief tenderness in the patient's epigastrium. The patient was monitored and about 12 h after hospitalization, ill appearance, respiratory (respiratory distress) symptoms, and high fever were reported for the patient. According to the examination, the patient was immediately transferred to the operating room and underwent laparotomy. During the operation, contrary to our expectations, a lot of blood (about 1000 cc) was observed in the patient's abdomen. After blood suctioning, the left upper quadrant (LUQ) was bleeding and the rupture of the spleen could also be observed. Therefore, a splenectomy was performed. In the examinations performed for the patient, the patient's rtPCR test confirmed COVID-19. CONCLUSION: The evaluation of the spontaneous splenic rupture (SSR) in our case shows that this type of risk should also be considered in patients with COVID-19 who refer to medical centers with abdominal pain, and if more cases are reported, the correctness of this process can be commented on.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/complicações , Pneumonia Viral/diagnóstico , Esplenectomia , Ruptura Esplênica/diagnóstico , Ruptura Esplênica/etiologia , Dor Abdominal/etiologia , COVID-19 , Infecções por Coronavirus/terapia , Emergências , Hospitalização , Humanos , Laparotomia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/terapia , Ruptura Espontânea , SARS-CoV-2 , Ruptura Esplênica/cirurgia
6.
Sci Rep ; 10(1): 3659, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32108143

RESUMO

La0.7Sr0.3MnO3, a strong semi-metallic ferromagnet having robust spin polarization and magnetic transition temperature (TC) well above 300 K, has attracted significant attention as a possible candidate for a wide range of memory, spintronic, and multifunctional devices. Since varying the oxygen partial pressure during growth is likely to change the structural and other physical functionalities of La0.7Sr0.3MnO3 (LSMO) films, here we report detailed investigations on structure, along with magnetic behavior of LSMO films with same thickness (~30 nm) but synthesized at various oxygen partial pressures: 10, 30, 50, 100, 150, 200 and 250 mTorr. The observation of only (00 l) reflections without any secondary peaks in the XRD patterns confirms the high-quality synthesis of the above-mentioned films. Surface morphology of the films reveals that these films are very smooth with low roughness, the thin films synthesized at 150 mTorr having the lowest average roughness. The increasing of magnetic TC and sharpness of the magnetic phase transitions with increasing oxygen growth pressure suggests that by decreasing the oxygen growth pressure leads to oxygen deficiencies in grown films which induce oxygen inhomogeneity. Thin films grown at 150 mTorr exhibits the highest magnetization with TC = 340 K as these thin films possess the lowest roughness and might exhibit lowest oxygen vacancies and defects. Interpretation and significance of these results in the 30 nm LSMO thin films prepared at different oxygen growth pressures are also presented, along with the existence and growth pressure dependence of negative remanent magnetization (NRM) of the above-mentioned thin films.

7.
J Phys Condens Matter ; 30(40): 405804, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30168452

RESUMO

The observation of inverted magnetic hysteresis loops and negative magnetic remanence (NRM) in a 7.6 nm thin film of La0.7Sr0.3MnO3 grown on SrTiO3 substrates is reported. The film was grown employing pulsed laser deposition and characterized by reflection high-energy electron diffraction during growth and using x-ray reflectivity measurements post-growth. Magnetic properties of the film were measured from 5 K to 400 K under both the field-cooled (FC) and zero-field-cooled (ZFC) conditions. The observed results of inverted magnetic hysteresis loops and NRM are interpreted in terms of the co-existence of a magnetically inhomogeneous region consisting of superparamagnetic spin clusters with a blocking temperature T B = 240 K and the ferromagnetic state with an ordering temperature T C = 290 K. Hysteresis loop inversion is observed in the temperature region of T B < T < T C whereas NRM appears in the mixed superparamagnetic and ferromagnetic states for T < T C down to 5 K. These observations of hysteresis loop inversion and NRM are related to the magneto-static interaction between the superparamagnetic and ferromagnetic phases leading to anti-alignment of spin of both magnetic phases with respect to each other.

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