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1.
iScience ; 27(6): 109851, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38784023

RESUMEN

The development of tyrosine kinase inhibitors (TKIs) has revolutionarily increased the overall survival of patients with chronic myeloid leukemia (CML). However, drug resistance remains a major obstacle. Here, we demonstrated that a BCR-ABL1-independent long non-coding RNA, IRAIN, is constitutively expressed at low levels in CML, resulting in imatinib resistance. IRAIN knockdown decreased the sensitivity of CD34+ CML blasts and cell lines to imatinib, whereas IRAIN overexpression significantly increased sensitivity. Mechanistically, IRAIN downregulates CD44, a membrane receptor favorably affecting TKI resistance, by binding to the nuclear factor kappa B subunit p65 to reduce the expression of p65 and phosphorylated p65. Therefore, the demethylating drug decitabine, which upregulates IRAIN, combined with imatinib, formed a dual therapy strategy which can be applied to CML with resistance to TKIs.

2.
Biomed Pharmacother ; 168: 115801, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37918257

RESUMEN

Heart diseases are the primary cause of mortality and morbidity worldwide which inflict a heavy social and economic burden. Among heart diseases, most deaths are due to myocardial infarction (MI) or heart attack, which occurs when a decrement in blood flow to the heart causes injury to cardiac tissue. Despite several available diagnostic, therapeutic, and prognostic approaches, heart disease remains a significant concern. Exosomes are a kind of small extracellular vesicles released by different types of cells that play a part in intercellular communication by transferring bioactive molecules important in regenerative medicine. Many studies have reported the diagnostic, therapeutic, and prognostic role of exosomes in various heart diseases. Herein, we reviewed the roles of exosomes as new emerging agents in various types of heart diseases, including ischemic heart disease, cardiomyopathy, arrhythmia, and valvular disease, focusing on pathogenesis, therapeutic, diagnostic, and prognostic roles in different areas. We have also mentioned different routes of exosome delivery to target tissues, the effects of preconditioning and modification on exosome's capability, exosome production in compliance with good manufacturing practice (GMP), and their ongoing clinical applications in various medical contexts to shed light on possible clinical translation.


Asunto(s)
Infarto del Miocardio , Isquemia Miocárdica , Humanos , Isquemia Miocárdica/terapia , Infarto del Miocardio/patología , Comunicación Celular/fisiología , Medicina Regenerativa , Antiinflamatorios
3.
Iran J Child Neurol ; 17(3): 55-67, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37637783

RESUMEN

Objectives: The present investigation has been done to study the behavioral effects of donepezil in autistic children, given that not much research has been carried out concerning using this drug for treating autism. Materials & Methods: A cross-sectional and analytic-descriptive study was done on twenty patients with autism, aged 4-17, who visited the neurology clinic of Gorgan's Taleghani Pediatric Hospital and Yasha Pediatric Autism Clinic, Iran from 2019 to 2020. Demographic information, including sex, age, father's education, mother's education ,patient's education, family status, other problems, and ethnicity, were documented using a checklist, having been filled in during interviews with the parents. Before the trial, ABC cognitive and behavioral tests were taken to determine the children's current status. After the tests, these children received a daily dose of donepezil (10mg) before sleep for three months. At the end of the three months, the cognitive and behavioral tests were taken from the children once again. In order to analyze the effects of different factors on the studied variables, including irritability, lethargy, stereotypic behavior, hyperactivity, and inappropriate speech before and after the administration of donepezil in patients, a generalized linear model and to test the effects of donepezil on the studied variables, paired t-test was used. Results: In this study, twenty patients were registered for the investigation, 12 (60%) male and eight (40%) female. Age groups 5-6 had the highest frequency, and age group 17 had the lowest. Regardingthe parents' education, the highest frequency was for bachelor's degrees, and the lowest was for less-than-high school education and master's degree. The highest frequency for the patients' education was kindergarten (60%), and then groups without education (20%) and elementary school-level education (15%). Most of the studied patients (80%) did not have other problems besides autism, and only 20% had other problems besides autism. The family status of 15% of the families was 'separated,' and ethnically, most patients (80%) were Fars, while the rest (20%) were Turkmen. None of the analyzed factors (age, sex, father's education, mother's education, patient's education, other problems, family status, and ethnicity) had a significant effect on the studied variables after the administration of donepezil. Among the studied variables prior to the administration of donepezil and among the analyzed factors, the father's education, the patient's education, other problems, and family status had only a significant effect on stereotypic behavior. The present research findings of the present research indicated that all the studied variables, including irritability, lethargy, stereotypic behavior, hyperactivity, and inappropriate speech, were significantly decreased toward the desired goal. The decreased amounts in irritability, lethargy, stereotypic behavior, hyperactivity, and inappropriate speech after the administration of donepezil were, respectively, 38%, 44%, 54%, 41%, and 54% and on average, these behaviors were reduced by 46%. Conclusion: The present investigation has shown that all the studied variables, including irritability, lethargy, stereotypic behavior, hyperactivity, and inappropriate speech, were significantly decreased towards the desired goal by 46%. This significant decrease is indicative of the effectiveness of the treatment of autism patients with donepezil, and therefore, this drug can be placed as a prominent and essential part of the medical therapy of autism.

4.
J Surg Oncol ; 128(3): 430-437, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37537979

RESUMEN

The health-related quality of life of patients with extremity soft tissue sarcoma (STS) is not precisely captured by current patient-reported outcome measures. Although functional impairment is central to their concerns, multiple sources of distress, emotional restoration, coping strategies, and somatic symptoms are crucial in approaching patients with extremity STS.


Asunto(s)
Sarcoma , Neoplasias de los Tejidos Blandos , Humanos , Calidad de Vida , Sarcoma/diagnóstico , Extremidades , Medición de Resultados Informados por el Paciente
5.
Stem Cell Res Ther ; 14(1): 174, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37408043

RESUMEN

BACKGROUND: Critical limb ischemia (CLI) is associated with increased risk of tissue loss, leading to significant morbidity and mortality. Therapeutic angiogenesis using cell-based treatments, notably mesenchymal stem cells (MSCs), is essential for enhancing blood flow to ischemic areas in subjects suffering from CLI. The objective of this study was to evaluate the feasibility of using placenta-derived mesenchymal stem cells (P-MSCs) in patients with CLI. METHODS: This phase I dose-escalation study investigated P-MSCs in nine CLI patients who were enrolled into each of the two dosage groups (20 × 106 and 60 × 106 cells), delivered intramuscularly twice, two months apart. The incidence of treatment-related adverse events was the primary endpoint. The decrease in inflammatory cytokines, improvement in the ankle-brachial pressure index (ABI), maximum walking distance, vascular collateralization, alleviation of rest pain, healing of ulceration, and avoidance of major amputation in the target leg were the efficacy outcomes. RESULTS: All dosages of P-MSCs, including the highest tested dose of 60 × 106 cells, were well tolerated. During the 6-month follow-up period, there was a statistically significant decrease in IL-1 and IFN-γ serum levels following P-MSC treatment. The blood lymphocyte profile of participants with CLI did not significantly differ, suggesting that the injection of allogeneic cells did not cause T-cell proliferation in vivo. We found clinically substantial improvement in rest pain, ulcer healing, and maximum walking distance after P-MSC implantation. In patients with CLI, we performed minor amputations rather than major amputations. Angiography was unable to demonstrate new small vessels formation significantly. CONCLUSION: The observations from this phase I clinical study indicate that intramuscular administration of P-MSCs is considered safe and well tolerated and may dramatically improve physical performance and minimize inflammatory conditions in patients with CLI. TRIAL REGISTRATION: IRCT, IRCT20210221050446N1. Registered May 09, 2021.


Asunto(s)
Isquemia Crónica que Amenaza las Extremidades , Células Madre Mesenquimatosas , Embarazo , Humanos , Femenino , Placenta , Isquemia/terapia , Dolor , Resultado del Tratamiento
6.
Cancers (Basel) ; 15(5)2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36900233

RESUMEN

Histology has not been accepted as a valid predictor of the biological behavior of extra-meningeal solitary fibrous tumors (SFTs). Based on the lack of a histologic grading system, a risk stratification model is accepted by the WHO to predict the risk of metastasis; however, the model shows some limitations to predict the aggressive behavior of a low-risk/benign-appearing tumor. We conducted a retrospective study based on medical records of 51 primary extra-meningeal SFT patients treated surgically with a median follow-up of 60 months. Tumor size (p = 0.001), mitotic activity (p = 0.003), and cellular variants (p = 0.001) were statistically associated with the development of distant metastases. In cox regression analysis for metastasis outcome, a one-centimeter increment in tumor size enhanced the expected metastasis hazard by 21% during the follow-up time (HR = 1.21, CI 95% (1.08-1.35)), and each increase in the number of mitotic figures escalated the expected hazard of metastasis by 20% (HR = 1.2, CI 95% (1.06-1.34)). Recurrent SFTs presented with higher mitotic activity and increased the likelihood of distant metastasis (p = 0.003, HR = 12.68, CI 95% (2.31-69.5)). All SFTs with focal dedifferentiation developed metastases during follow-up. Our findings also revealed that assembling risk models based on a diagnostic biopsy underestimated the probability of developing metastasis in extra-meningeal SFTs.

7.
Cancer Rep (Hoboken) ; 6(1): e1735, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36253342

RESUMEN

BACKGROUND: With the progression of next-generation sequencing technologies, researchers have identified numerous variants of the regulator of telomere elongation helicase 1 (RTEL1) gene that are associated with a broad spectrum of phenotypic manifestations, including malignancies. At the molecular level, RTEL1 is involved in the regulation of the repair, replication, and transcription of deoxyribonucleic acid (DNA) and the maintenance of telomere length. RTEL1 can act both as a promotor and inhibitor of tumorigenesis. Here, we review the potential mechanisms implicated in the malignant transformation of tissues under conditions of RTEL1 deficiency or its aberrant overexpression. RECENT FINDINGS: A major hemostatic challenge during RTEL1 dysfunction could arise from its unbalanced activity for unwinding guanine-rich quadruplex DNA (G4-DNA) structures. In contrast, RTEL1 deficiency leads to alterations in telomeric and genome-wide DNA maintenance mechanisms, ribonucleoprotein metabolism, and the creation of an inflammatory and immune-deficient microenvironment, all promoting malignancy. Additionally, we hypothesize that functionally similar molecules could act to compensate for the deteriorated functions of RTEL1, thereby facilitating the survival of malignant cells. On the contrary, RTEL1 over-expression was directed toward G4-unwinding, by promoting replication fork progression and maintaining intact telomeres, may facilitate malignant transformation and proliferation of various pre-malignant cellular compartments. CONCLUSIONS: Therefore, restoring the equilibrium of RTEL1 functions could serve as a therapeutic approach for preventing and treating malignancies.


Asunto(s)
ADN Helicasas , Neoplasias , Telómero , Humanos , ADN , Neoplasias/genética , Telómero/genética , Microambiente Tumoral , ADN Helicasas/genética
8.
Stem Cell Res Ther ; 13(1): 462, 2022 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-36068595

RESUMEN

Critical limb ischemia (CLI), the terminal stage of peripheral arterial disease (PAD), is characterized by an extremely high risk of amputation and vascular issues, resulting in severe morbidity and mortality. In patients with severe limb ischemia with no alternative therapy options, such as endovascular angioplasty or bypass surgery, therapeutic angiogenesis utilizing cell-based therapies is vital for increasing blood flow to ischemic regions. Mesenchymal stem cells (MSCs) are currently considered one of the most encouraging cells as a regenerative alternative for the surgical treatment of CLI, including restoring tissue function and repairing ischemic tissue via immunomodulation and angiogenesis. The regenerative treatments for limb ischemia based on MSC therapy are still considered experimental. Despite recent advances in preclinical and clinical research studies, it is not recommended for regular clinical use. In this study, we review the immunomodulatory features of MSC besides the current understanding of different sources of MSC in the angiogenic treatment of CLI subjects and their potential applications as therapeutic agents. Specifically, this paper concentrates on the most current clinical application issues, and several recommendations are provided to improve the efficacy of cell therapy for CLI patients.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Tratamiento Basado en Trasplante de Células y Tejidos , Isquemia Crónica que Amenaza las Extremidades , Humanos , Isquemia/terapia , Recuperación del Miembro , Trasplante de Células Madre Mesenquimatosas/métodos , Resultado del Tratamiento
9.
World Neurosurg X ; 16: 100130, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35794902

RESUMEN

Objective: We sought to determine whether a posterior vertebral resection on congenital deformities of thoracolumbar and lumbar vertebrae leads to more complications and provides less correction. Methods: Twenty-three patients underwent a posterior vertebral resection for a rigid congenital spinal deformity, which included scoliosis (13 patients), kyphoscoliosis (6 patients), and pure kyphosis (4 patients). The surgeries involved removing 1 to 2 vertebrae using multiaxial pedicle screws in all but 2 of the patients. All surgeries were performed under intraoperative spinal cord monitoring. Thoracic curve, lumbar lordosis, focal kyphosis, shift, and sagittal vertical axis were collected at baseline and during the last follow-up (taking place after at least 3 years) and were then statistically analyzed. Results: The major curve correction was about 55% in cases of scoliosis, with focal kyphosis improving from 54.3 ± 19.1 degrees to 21.3 ± 15 degrees. Two patients experienced intraoperative neuromonitoring changes, with data returning to baseline without any surgical intervention. Sensory or motor palsy after the surgery was not reported in patients.Despite improving sagittal or coronal deformities, 8 patients experienced excessive sagittal decompensation during follow-up, 1 of whom underwent revision surgery. Sagittal decompensation was by far the most common complication. Larger kyphoscoliosis or focal kyphosis angles were preoperative risk factors for postoperative sagittal imbalance (P value < 0.05). Conclusions: Using a lumbar or thoracolumbar posterior vertebral resection enables surgeons to correct rigid curves in the pediatric population without major risk to nerve roots. The primary complications would be sagittal decompensation and the likelihood of undercorrection, which requires mindful addressing during the preoperative planning stages.

10.
Eur J Transl Myol ; 32(2)2022 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35587263

RESUMEN

Renal transplant therapy is essential in patients with End-Stage Renal Disease (ESRD). It is used in patients awaiting a kidney transplant or those who cannot be a transplant candidate. Central venous catheter is one of the most used access routes worldwide but has been recorded as the one with highest mortality and morbidity rate. Thromboembolic events have played a major part for that. This is a descriptive-analytical study, which conducted in a university treatment center in Tehran, Iran. A total of 225 patients were selected for this study that 108 were excluded because of our criteria. Statistical analysis was performed by SPSS v19 and a total of 117 patients were included in this study. The average age of the patients was 51.62±11.26. 79 (67.5%) and 38 (32.5%) patients had medial and lateral tip direction, respectively. The catheter of 85(72.6%) and 32(27.4%) patients was patent and occluded, respectively. The average catheter tip occlusion time in both groups was 22.5 and 7.5 months. Three-month, six-month, twelve-month, and twenty-four-month patency rate were 99%, 94%, 88%, and 30%, respectively. our findings suggest that medial direction of the tip of the catheter reduces complications caused in CVS. Because our study has been conducted in a small scale and there is lack of similar studies, our team suggests extension to a larger scale to confirm or not our results.

11.
J Vasc Nurs ; 40(1): 43-46, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35287833

RESUMEN

INTRODUCTION AND OBJECTIVE: Ultrasound of the saphenous vein and measurement of the vein diameter may have a role in determining the severity of varicose veins. This study aimed to compare the saphenous vein diameter with the CEAP classification, as the reference standard in determining the severity of chronic venous diseases, in patients with lower limbs varicose veins free from saphenous vein reflux. METHODS: In this cross-sectional study, 100 patients with lower limbs varicose veins (saphenous vein) and free from saphenous vein reflux were enrolled. Demographic data (age, gender, body mass index (BMI)) were collected using a checklist. The severity of varicose veins was determined using the standard CEAP classification. The saphenous vein diameter was measured using ultrasonography. RESULTS: Mean age of the patients was 43 years and there were 68 female patients. According to the CEAP classification, 13 patients had no varicose veins (CEAP class C0). However, 87 patients had varicose veins (65 patients with class C1, one patient with class C2, and 21 patients with class C3). Mean saphenous vein diameter in the whole sample was 6.7 mm. There was no significant relationship between the severity of varicose veins determined by CEAP classification and mean saphenous vein diameter measured by ultrasound. Mean saphenous vein diameter in C0, C1, C2, and C3 groups were respectively 1.7 mm, 6.7 mm, 8 mm, and 8.7 mm (P= 0.71). On the other hand, mean saphenous vein diameter was higher significantly in those with higher body mass index (BMI) and among older patients. CONCLUSION: The results of this study showed that saphenous vein diameter did not differ significantly between CEAP C0 through C4 classes. However, the severity of varicose vein was more prominent in older patients and those with higher BMI.


Asunto(s)
Várices , Insuficiencia Venosa , Adulto , Anciano , Enfermedad Crónica , Estudios Transversales , Femenino , Vena Femoral , Humanos , Masculino , Vena Safena/diagnóstico por imagen , Várices/diagnóstico por imagen , Insuficiencia Venosa/diagnóstico por imagen
12.
Transpl Immunol ; 71: 101524, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34990789

RESUMEN

Background Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) has been increasingly used as a therapeutic approach for hematological malignancies. Several potential strategies have been developed for treating or preventing allo-HSCT complications, specifically graft-versus-host disease (GVHD). GVHD could significantly affect the morbidity and mortality of patients after allo-HSCT. Curative treatment and prophylaxis regimens for GVHD could reduce GVHD incidence and improve survival rate. Among these therapeutic strategies, mesenchymal stem cell (MSCs) mediated immunomodulation has been explored widely in clinical trials. MSCs immunomodulation ability in GVHD correlates with the interactions of MSCs with innate and adaptive immune cells. However, signaling pathways responsible for MSCs' impact on GVHD regulation, like JAK/STAT, NOTCH, MAPK/ERK, and NFκß signaling pathways, have not been clearly described yet. This review aims to illuminate the effect of MSCs-mediated immunomodulation in GVHD management after allo-HSCT representing the role of MSCs therapy on signaling pathways in GVHD. Conclusion MSCs could potentially modulate immune responses, prevent GVHD, and improve survival after allo-HSCT. Previous studies have investigated different signaling pathways' contributions to MSCs immunoregulatory ability. Accordingly, targeting signaling pathways components involved in MSCs related GVHD regulation is proven to be beneficial.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Inmunidad , Inmunomodulación , Trasplante de Células Madre Mesenquimatosas/efectos adversos , Transducción de Señal
13.
Int J Oral Maxillofac Implants ; 36(6): 1159-1164, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34919616

RESUMEN

PURPOSE: This study was conducted to compare the radiographic, esthetic, and patient-reported outcome measures (PROMs) between immediate and delayed restorations of immediately placed single implants in the maxillary esthetic zone. MATERIALS AND METHODS: Forty patients with immediate single dental implants in the anterior maxilla were included in this study. Afterward, they were allocated either for immediate restoration with a provisional restoration (IR: 20 patients) or for a delayed restoration (DR: 20 patients). The evaluations were performed after 1 year of follow-up. RESULTS: No implant and prosthetic failures were observed during the 1-year follow-up. Two minor complications were found in two IR patients; however, no complication was reported in the DR group during the 1 year. Nevertheless, this difference was not statistically significant (P > .05). After 1 year, the mean marginal bone level changes (MBL) were 0.47 ± 0.29 mm and 0.54 ± 0.21 mm for IR and DR, respectively. There was no statistically significant difference between the two groups in terms of MBL (P = .3). Notably, the mean total pink esthetic score (PES) and white esthetic score (WES) after 1 year of follow-up were 11.2 ± 1.1 (PES) and 8 ± 1.02 (WES) for the immediate restoration, and 10.2 ± 0.97 (PES) and 7.65 ± 1.20 (WES) for the delayed restoration. Also, no statistically significant difference was found between IR and DR in terms of esthetic scores (P > .05). The patient satisfaction of these two groups had no statistically significant difference, except for the esthetic factor (P = .04). CONCLUSION: The immediate restoration and preferred esthetic satisfaction had similar outcomes compared with the delayed restoration.


Asunto(s)
Implantes Dentales , Maxilar , Humanos , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Medición de Resultados Informados por el Paciente
14.
Opt Express ; 29(23): 38359-38375, 2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34808890

RESUMEN

Terahertz radiation by optical rectification in single-walled highly aligned chiral carbon nanotubes (SWCNTs) irradiated by ultrashort laser pulses is comprehensively studied. We take into account the structural properties of SWCNTs, including the filling factor, alignment, and chirality, as well as the laser pulse parameters including the pulse duration and the wavelength. The second-order nonlinear susceptibility tensor and, consequently, polarization responsible for optical rectification in SWCNTs are derived based on symmetrical features.The effective dielectric constants of SWCNTs are also extracted using the effective medium approximation. Then, the propagation effects in terms of the group velocity dispersion and absorption at both pump and terahertz pulse frequency regions are investigated. By adjusting the laser and the structure effective parameters among those practically feasible, minimum velocity mismatch required for optimum optical rectification and coherent amplification at terahertz frequencies in SWCNTs are introduced. Comparing the electric field waveform and the spectrum of the generated terahertz pulses under various conditions reveals that SWCNTs with higher alignment and lower filling factor at chirality (6,4) irradiated by an ultrashort laser pulse with the wavelength of 1550 nm could provide the conditions for maximum terahertz radiation generation.

15.
Ann Surg Oncol ; 28(11): 6861-6867, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33512676

RESUMEN

BACKGROUND: Solitary fibrous tumor (SFT) is a rare mesenchymal tumor with an intermediate tendency to metastasize. Meningeal hemangiopericytoma (HPC), arising in the meningeal membranes, also is considered an SFT. Although SFT is assumed to show an unpredictable behavior, the authors defined some factors associated with its aggressive behavior. METHODS: This retrospective study was based on the medical records of 81 SFT patients treated surgically, with the median follow-up period of 59 months. The patients were assigned to three histopathologic groups based on the 2016 WHO classification: group 1 (SFT, 29 patients), group 2 (cellular SFT/hemangiopericytoma [HPC], 27 patients), and group 3 (malignant SFT/anaplastic HPC, 25 patients). RESULTS: The SFT histopathologic classification was associated with distant metastasis (DM) (p = 0.007). The multivariate analysis showed that cellular SFT had an independent impact on DM (odds ratio [OR] = 25.42; p = 0.006). Tumor diameter larger than 7.25 cm was correlated with DM (p = 0.010) and the patient's disease-specific death (DSD) (p = 0.007). A 1-cm increase in tumor diameter enhanced the likelihood of metastasis by 1.26 (OR = 1.26; 95% confidence interval [CI], 1.05-1.53). Tumors originating from the central nervous system (CNS) showed a greater tendency toward local recurrence (LR) (p = 0.039) and DM (p = 0.05). Radiotherapy had no association with LR, DM, or DSD. The 10-year disease-specific survival rate was 82.7%. CONCLUSIONS: Tumor size and histopathologic diagnosis are the predictors of SFT's aggressive behavior. Cellular SFTs behave as aggressively as the malignant form of the tumor. A SFT grading based on SFT cellularity would contribute to anticipation of its aggressive behavior.


Asunto(s)
Hemangiopericitoma , Tumores Fibrosos Solitarios , Humanos , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Tumores Fibrosos Solitarios/cirugía , Tasa de Supervivencia
16.
ACS Omega ; 5(26): 16053-16063, 2020 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-32656427

RESUMEN

The present study is an attempt to examine the effect of biodiesel chemical structure on the diesel engine combustion properties and exhaust emissions. For this purpose, nine new types of oil (second generation) are used for producing biodiesel. Also, fatty acid profiles are determined by gas chromatography. Results show that Urtica biodiesel causes the highest soot emission (0.98 vol %) and the minimum NOx emission (460 ppm). A decrease in CN increases NOx and decreases soot emission at high engine loads. The longest chain is gained via Urtica biodiesel, and the increase of carbon chain length enhances soot emission. The increase of oxygen-to-carbon (O/C) ratio also affects the soot emissions and reduces the process (the O/C ratio is 0.1087 for Urtica). The increase of long-chain biodiesel fatty acids from C18 to C24 reduces the NOx emissions (C18-C24; 97.43 wt % for Urtica); moreover, there is a direct correlation between the increased carbon chain length and the amount of enthalpy. As the amount of unsaturated acids grows (94.93 wt % unsaturated fatty acids for Urtica), the value of the output soot is enhanced. Also, the increase in hydrogen-to-carbon ratio (1.8457 molar for Urtica) decreases the soot emissions. The increase in carbon chain length and decrease in O/C affect the HC and CO emissions; therefore, Urtica biodiesel had the maximum CO and HC emission (0.036 vol % and 6.11 ppm, respectively). In addition, the reduction of fuel consumption increased the NOx emission and reduced the HC, CO, and soot emission.

17.
Cell Tissue Bank ; 21(3): 377-403, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32415569

RESUMEN

Cardiovascular diseases are a leading cause of death. Vascular surgery is mainly used to solve this problem. However, the generation of a functional and suitable substitute for small diameter (< 6 mm) displacement is challengeable. Moreover, synthetic prostheses, made of polyethylene terephthalate and extended polytetrafluoroethylene show have shown insufficient performance. Therefore, the challenges dominating the use of autografts have prevented their efficient use. Tissue engineering is highlighted in regenerative medicine perhaps in aiming to address the issue of end-stage organ failure. While organs and complex tissues require the vascular supply to support the graft survival and render the bioartificial organ role, vascular tissue engineering has shown to be a hopeful method for cell implantation by the production of tissues in vitro. Bioreactors are a salient point in vascular tissue engineering due to the capability for reproducible and controlled variations showing a new horizon in blood vessel substitution. This review strives to display the overview of current concepts in the development of small-diameter by using bioreactors. In this work, we show a critical look at different factors for developing small-diameter and give suggestions for future studies.


Asunto(s)
Reactores Biológicos , Prótesis Vascular , Ingeniería de Tejidos/métodos , Ingeniería de Tejidos/tendencias , Animales , Humanos , Miocitos del Músculo Liso/fisiología , Perfusión , Publicaciones
18.
J Korean Assoc Oral Maxillofac Surg ; 46(1): 41-48, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32158680

RESUMEN

OBJECTIVES: One of the most common complications of bilateral sagittal split ramus osteotomy (BSSRO) is neurosensory impairment of the inferior alveolar nerve (IAN). Accurate preoperative determination of the position of the IAN canal within the mandible using cone-beam computed tomography (CBCT) is recommended to prevent IAN dysfunction during BSSRO and facilitate neurosensory improvement after BSSRO. MATERIALS AND METHODS: This randomized clinical trial consisted of 86 surgical sites in 43 patients (30 females and 13 males), including 21 cases (42 sides) and 22 controls (44 sides). Panoramic and lateral cephalographs were obtained from all patients. In the experimental group, CBCT was also performed from both sides of the ramus and mandibular body. Neurosensory function of the IAN was subjectively assessed using a 5-point scale preoperatively and 7 days, 1 month, 3 months, 6 months, and 12 months post-surgery. Data were analyzed using Fisher's test, Spearman's test, t-test, linear mixed-model regression, and repeated-measures ANCOVA (α=0.05, 0.01). RESULTS: Mean sensory scores in the control group were 1.57, 2.61, 3.34, 3.73, and 4.20 over one year and were 1.69, 3.00, 3.60, 4.19, and 4.48 in the CBCT group. Significant effects were detected for CBCT intervention (P=0.002) and jaw side (P=0.003) but not for age (P=0.617) or displacement extent (P=0.122). CONCLUSION: Preoperative use of CBCT may help surgeons to practice more conservative surgery. Neurosensory deficits might heal faster on the right side.

19.
Clin Orthop Surg ; 11(4): 422-426, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31788165

RESUMEN

BACKGROUND: Surgery on the lower thoracic and lumbosacral spine is possible with both general and spinal anesthesia, but most spine surgeons are reluctant to perform the surgery with spinal anesthesia. We aimed to conduct a survey on the short-term outcome of microlumbar discectomy in the patients who had been treated under general or spinal anesthesia. METHODS: In this prospective study, we performed a survey on 72 patients who underwent microlumbar discectomy under general anesthesia (group A) or spinal anesthesia (group B). Demographic characteristics, American Society of Anesthesiologists physical status, duration of operation, blood loss, and complications were all documented. Preoperative and early postoperative (at the time of discharge) disability and pain were assessed by using Japanese Orthopedic Association (JOA) scoring system and a visual analog scale questionnaire. RESULTS: The two groups were homogenous preoperatively. The mean intraoperative blood loss was less and the mean operating time was shorter in group A than in group B, but there was no statistically significant difference between groups. The rate of postoperative improvement in JOA score and improvement in pain were similar between groups. Anesthetic complications were unremarkable. CONCLUSIONS: Simple lumbar disc operations in the otherwise healthy patients can be safely performed under either spinal or general anesthesia. Both anesthetic methods led to comparable outcomes with minimal complications.


Asunto(s)
Anestesia General/métodos , Anestesia Raquidea/métodos , Discectomía , Desplazamiento del Disco Intervertebral/cirugía , Vértebras Lumbares/cirugía , Microcirugia , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Dimensión del Dolor , Estudios Prospectivos
20.
Sci Adv ; 5(9): eaax1311, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31548987

RESUMEN

The growing timber manufacturing industry faces challenges due to increasing geometric complexity of architectural designs. Complex and structurally efficient curved geometries are nowadays easily designed but still involve intensive manufacturing and excessive machining. We propose an efficient form-giving mechanism for large-scale curved mass timber by using bilayered wood structures capable of self-shaping by moisture content changes. The challenge lies in the requirement of profound material knowledge for analysis and prediction of the deformation in function of setup and boundary conditions. Using time- and moisture-dependent mechanical simulations, we demonstrate the contributions of different wood-specific deformation mechanisms on the self-shaping of large-scale elements. Our results outline how to address problems such as shape prediction, sharp moisture gradients, and natural variability in material parameters in light of an efficient industrial manufacturing.

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