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1.
Int J Reprod Biomed ; 22(5): 411-416, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-39091431

RESUMEN

Background: Turner syndrome (TS) is recognized with partial or complete loss of the second sex chromosome, occurring in approximately one in 2500 live births, and related to high failure of pregnancy. However, along with the advantage of assisted reproductive technology, the cases of TS pregnant women have been recently addressed worldwide. Therefore, the reproductive health of TS pregnant women should be a concern by physicians and obstetricians, particularly, in the low-middle income countries with low-resource settings. Case Presentation: Here, we describe a rare case of term pregnancy on a TS woman (45, XO) receiving oocyte donation at a private fertility center. Later, the woman was monitored uneventfully during antenatal care and hospitalized at our center for a cesarean delivery with favorable pregnancy outcomes at term. Conclusion: To our knowledge, this is the first report relating to a particular pathology in Vietnam. Through this case report, we would like to emphasize the novel opportunity for TS women desiring parents, thus raising an appropriate awareness of healthcare providers.

2.
Stat Biosci ; 16(2): 321-346, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39091460

RESUMEN

Estimating sample size and statistical power is an essential part of a good epidemiological study design. Closed-form formulas exist for simple hypothesis tests but not for advanced statistical methods designed for exposure mixture studies. Estimating power with Monte Carlo simulations is flexible and applicable to these methods. However, it is not straightforward to code a simulation for non-experienced programmers and is often hard for a researcher to manually specify multivariate associations among exposure mixtures to set up a simulation. To simplify this process, we present the R package mpower for power analysis of observational studies of environmental exposure mixtures involving recently-developed mixtures analysis methods. The components within mpower are also versatile enough to accommodate any mixtures methods that will developed in the future. The package allows users to simulate realistic exposure data and mixed-typed covariates based on public data set such as the National Health and Nutrition Examination Survey or other existing data set from prior studies. Users can generate power curves to assess the trade-offs between sample size, effect size, and power of a design. This paper presents tutorials and examples of power analysis using mpower.

3.
mBio ; 15(8): e0131624, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-38953637

RESUMEN

Human intestinal enteroids (HIEs) are gaining recognition as physiologically relevant models of the intestinal epithelium. While HIEs from adults are used extensively in biomedical research, few studies have used HIEs from infants. Considering the dramatic developmental changes that occur during infancy, it is important to establish models that represent infant intestinal characteristics and physiological responses. We established jejunal HIEs from infant surgical samples and performed comparisons to jejunal HIEs from adults using RNA sequencing (RNA-Seq) and morphologic analyses. We then validated differences in key pathways through functional studies and determined whether these cultures recapitulate known features of the infant intestinal epithelium. RNA-Seq analysis showed significant differences in the transcriptome of infant and adult HIEs, including differences in genes and pathways associated with cell differentiation and proliferation, tissue development, lipid metabolism, innate immunity, and biological adhesion. Validating these results, we observed a higher abundance of cells expressing specific enterocyte, goblet cell, and enteroendocrine cell markers in differentiated infant HIE monolayers, and greater numbers of proliferative cells in undifferentiated 3D cultures. Compared to adult HIEs, infant HIEs portray characteristics of an immature gastrointestinal epithelium including significantly shorter cell height, lower epithelial barrier integrity, and lower innate immune responses to infection with an oral poliovirus vaccine. HIEs established from infant intestinal tissues reflect characteristics of the infant gut and are distinct from adult cultures. Our data support the use of infant HIEs as an ex vivo model to advance studies of infant-specific diseases and drug discovery for this population. IMPORTANCE: Tissue or biopsy stem cell-derived human intestinal enteroids are increasingly recognized as physiologically relevant models of the human gastrointestinal epithelium. While enteroids from adults and fetal tissues have been extensively used for studying many infectious and non-infectious diseases, there are few reports on enteroids from infants. We show that infant enteroids exhibit both transcriptomic and morphological differences compared to adult cultures. They also differ in functional responses to barrier disruption and innate immune responses to infection, suggesting that infant and adult enteroids are distinct model systems. Considering the dramatic changes in body composition and physiology that begin during infancy, tools that appropriately reflect intestinal development and diseases are critical. Infant enteroids exhibit key features of the infant gastrointestinal epithelium. This study is significant in establishing infant enteroids as age-appropriate models for infant intestinal physiology, infant-specific diseases, and responses to pathogens.


Asunto(s)
Mucosa Intestinal , Humanos , Lactante , Mucosa Intestinal/citología , Mucosa Intestinal/inmunología , Adulto , Diferenciación Celular , Yeyuno/citología , Yeyuno/inmunología , Transcriptoma , Organoides , Inmunidad Innata , Femenino , Masculino , Recién Nacido , Enterocitos
4.
J Neuropathol Exp Neurol ; 83(9): 736-744, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38964366

RESUMEN

The circadian clock (CC) has biological and clinical implications in gliomas. Most studies focused on CC effects on the tumor microenvironment and the application of chronotherapy. The present study focused on CC gene expression patterns and intracellular oncogenic activities. Glioma gene expression data were collected from The Human Cancer Genome Atlas (TCGA) project. After applying inclusion and exclusion criteria, we selected 666 patients from TCGA-GBM and TCGA-LGG projects and included important clinicopathological variables. The entire cohort was subjected to clustering analysis and divided into CC1 and CC2 subtypes based on statistical, biological, and clinical criteria. CC2 gliomas showed higher expression of BMAL1 and CRY1 and lower expression of CRY2 and PER2 (adjusted P < .001). CC2 gliomas had q higher activity of cell proliferation, metabolic reprogramming, angiogenesis, hypoxia, and many oncogenic signals (P < .001). The CC2 subtype contained a higher proportion of glioblastomas (P < .001) and had a worse prognosis (P < .001). Stratified Kaplan-Meier and multivariable Cox analyses illustrated that the CC subtype is an independent prognostic factor to clinicopathological characteristics (P < .001), genetic aberrations (P = .006), and biological processes (P < .001). Thus, this study shows statistical evidence of CC subtypes and their biological, and clinicopathological significance in adult gliomas.


Asunto(s)
Neoplasias Encefálicas , Relojes Circadianos , Epigénesis Genética , Glioma , Humanos , Glioma/genética , Glioma/patología , Glioma/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Relojes Circadianos/genética , Femenino , Masculino , Adulto , Persona de Mediana Edad , Regulación Neoplásica de la Expresión Génica/genética , Anciano , Estudios de Cohortes
5.
RSC Adv ; 14(29): 20466-20478, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38946772

RESUMEN

In recent years, smartphones have been integrated into rapid colorimetric sensors for heavy metal ions, but challenges persist in accuracy and efficiency. Our study introduces a novel approach to utilize biogenic gold nanoparticle (AuNP) sensors in conjunction with designing a lightbox with a color reference and machine learning for detection of Fe3+ ions in water. AuNPs were synthesized using the aqueous extract of Eleutherine bulbosa leaf as reductants and stabilizing agents. Physicochemical analyses revealed diverse AuNP shapes and sizes with an average size of 19.8 nm, with a crystalline structure confirmed via SAED and XRD techniques. AuNPs exhibited high sensitivity and selectivity in detection of Fe3+ ions through UV-vis spectroscopy and smartphones, relying on nanoparticle aggregation. To enhance image quality, we developed a lightbox and implemented a reference color value for standardization, significantly improving performance of machine learning algorithms. Our method achieved approximately 6.7% higher evaluation metrics (R 2 = 0.8780) compared to non-normalized approaches (R 2 = 0.8207). This work presented a promising tool for quantitative Fe3+ ion analysis in water.

6.
Int J Mol Sci ; 25(11)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38892007

RESUMEN

Understanding protein-protein interactions (PPIs) helps to identify protein functions and develop other important applications such as drug preparation and protein-disease relationship identification. Deep-learning-based approaches are being intensely researched for PPI determination to reduce the cost and time of previous testing methods. In this work, we integrate deep learning with feature fusion, harnessing the strengths of both approaches, handcrafted features, and protein sequence embedding. The accuracies of the proposed model using five-fold cross-validation on Yeast core and Human datasets are 96.34% and 99.30%, respectively. In the task of predicting interactions in important PPI networks, our model correctly predicted all interactions in one-core, Wnt-related, and cancer-specific networks. The experimental results on cross-species datasets, including Caenorhabditis elegans, Helicobacter pylori, Homo sapiens, Mus musculus, and Escherichia coli, also show that our feature fusion method helps increase the generalization capability of the PPI prediction model.


Asunto(s)
Aprendizaje Profundo , Mapeo de Interacción de Proteínas , Humanos , Animales , Mapeo de Interacción de Proteínas/métodos , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Ratones , Biología Computacional/métodos , Mapas de Interacción de Proteínas , Bases de Datos de Proteínas
7.
Angew Chem Int Ed Engl ; : e202408504, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884612

RESUMEN

The photocatalytic conversion of biomass and plastic waste provides opportunities for sustainable fuel and chemical production. Heterogeneous photocatalysts, typically composed of semiconductors with distinctive redox properties in their conduction band (CB) and valence band (VB), facilitate both the oxidative and reductive valorization of organic feedstocks. This article provides a comprehensive overview of recent advancements in the photorefinery of biomass and plastics from the perspective of the redox properties of photocatalysts. We explore the roles of the VB and CB in enhancing the value-added conversion of biomass and plastics via various pathways. Our aim is to bridge the gap between photocatalytic mechanisms and renewable carbon feedstock valorization, inspiring further development in photocatalytic refinery of biomass and plastics.

8.
Heliyon ; 10(11): e32168, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38882270

RESUMEN

Electronic word of mouth (eWOM) on social networking sites (SNS) has become crucial in shaping online consumers' purchase intentions, reflecting the growing reliance on rich nature of user-generated content and recommendations shared on these platforms. This study aims to investigate the intricate relationships among different factors of eWOM information, including information credibility, information usefulness, information adoption, attitude towards information, and their impacts on online purchase intention. This study draws upon the Information Adoption Model (IAM) and the Information Acceptance Model (IACM) foundation theory which reveal the steps individuals take in adopting new information, and focuses on how perceptions and attitudes towards information shape acceptance. The study used a quantitative approach, utilizing a structured questionnaire to collect data from 337 Vietnamese individuals actively engaged in eWOM activities on various SNS platforms. Statistical analysis was conducted using partial least squares structural equation modeling (PLS-SEM). The findings show that information credibility significantly influences both information usefulness and adoption. Interestingly, while information usefulness shapes user attitudes, it does not directly impact online purchase intention. Similarly, a positive attitude toward eWOM does not necessarily lead to information adoption. This suggests that consumers may hold favorable views of eWOM content without actively adopting it. Information adoption emerges as a critical determinant of online purchase intention, emphasizing the importance of promoting user engagement and trust in eWOM information. These findings contribute to a deeper understanding of online consumer behavior and provide valuable guidance for stakeholders seeking to leverage eWOM effectively in digital marketing.

9.
AJOG Glob Rep ; 4(2): 100339, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38725540

RESUMEN

Spontaneous idiopathic vulvar edema during the second trimester is a rare condition. The approach to managing this condition involves relieving symptoms, identifying underlying causes, and implementing appropriate treatment. Managing such cases during pregnancy is challenging because of concerns for potential adverse fetal outcomes. Conservative management expects the condition to be relieved spontaneously postpartum, whereas invasive treatment offers a more rapid resolution. Treatment choices are controversial because each method has its pros and cons and influences the delivery process to a certain extent. Surgical drainage becomes a viable option when patients are not responsive to medications. We report a case of spontaneous massive vulvar edema in a 22-year-old primigravida in her 23rd week of pregnancy. After ruling out other notable causes of vulvar edema, we decided to intervene using an invasive procedure because she complained of progressive symptoms and discomfort. Subsequently, the edema subsided postprocedure, and the patient experienced successful labor with no complications. This report aims to alert clinicians that drainage attempts should be considered in pregnant patients with worsening symptoms.

12.
BMC Pregnancy Childbirth ; 24(1): 228, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38566074

RESUMEN

BACKGROUND: Placenta accreta spectrum disorders (PASDs) increase the mortality rate for mothers and newborns over a decade. Thus, the purpose of the study is to evaluate the neonatal outcomes in emergency cesarean section (CS) and planned surgery as well as in Cesarean hysterectomy and the modified one-step conservative uterine surgery (MOSCUS). The secondary aim is to reveal the factors relating to poor neonatal outcomes. METHODS: This was a single-center retrospective study conducted between 2019 and 2020 at Tu Du Hospital, in the southern region of Vietnam. A total of 497 pregnant women involved in PASDs beyond 28 weeks of gestation were enrolled. The clinical outcomes concerning gestational age, birth weight, APGAR score, neonatal intervention, neonatal intensive care unit (NICU) admission, and NICU length of stay (LOS) were compared between emergency and planned surgery, between the Cesarean hysterectomy and the MOSCUS. The univariate and multivariable logistic regression were used to assess the adverse neonatal outcomes. RESULTS: Among 468 intraoperatively diagnosed PASD cases who underwent CS under general anesthesia, neonatal outcomes in the emergency CS (n = 65) were significantly poorer than in planned delivery (n = 403). Emergency CS increased the odds ratio (OR) for earlier gestational age, lower birthweight, lower APGAR score at 5 min, higher rate of neonatal intervention, NICU admission, and longer NICU LOS ≥ 7 days with OR, 95% confidence interval (CI) were 10.743 (5.675-20.338), 3.823 (2.197-6.651), 5.215 (2.277-11.942), 2.256 (1.318-3.861), 2.177 (1.262-3.756), 3.613 (2.052-6.363), and 2.298 (1.140-4.630), respectively, p < 0.05. Conversely, there was no statistically significant difference between the neonatal outcomes in Cesarean hysterectomy (n = 79) and the MOSCUS method (n = 217). Using the multivariable logistic regression, factors independently associated with the 5-min-APGAR score of less than 7 points were time duration from the skin incision to fetal delivery (min) and gestational age (week). One minute-decreased time duration from skin incision to fetal delivery contributed to reduce the risk of adverse neonatal outcome by 2.2% with adjusted OR, 95% CI: 0.978 (0.962-0.993), p = 0.006. Meanwhile, one week-decreased gestational age increased approximately two fold odds of the adverse neonatal outcome with adjusted OR, 95% CI: 1.983 (1.600-2.456), p < 0.0001. CONCLUSIONS: Among pregnancies with PASDs, the neonatal outcomes are worse in the emergency group compared to planned group of cesarean section. Additionally, the neonatal comorbidities in the conservative surgery using the MOSCUS method are similar to Cesarean hysterectomy. Time duration from the skin incision to fetal delivery and gestational age may be considered in PASD surgery. Further data is required to strengthen these findings.


Asunto(s)
Cesárea , Placenta Accreta , Embarazo , Recién Nacido , Femenino , Humanos , Cesárea/efectos adversos , Estudios Retrospectivos , Vietnam/epidemiología , Placenta Accreta/cirugía , Placenta Accreta/etiología , Peso al Nacer
13.
Int J Surg Case Rep ; 118: 109603, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38642432

RESUMEN

INTRODUCTION AND IMPORTANCE: Abdominal ectopic pregnancy (AEP) located at hepatic region and pelvic-wall ectopic pregnancy (EP) are rare entities, that provoking a potentially life-threatening condition. Due to insufficient data, a proper management of non-specific types remains a challenge for all gynecologists worldwide. CASE PRESENTATION: Two child-bearing age women were hospitalized due to delayed menstruation and a urine pregnancy test was positive without a determination of intrauterine pregnancy. The first EP case was located at the pelvic wall which identified incidentally during laparoscopy for a presumed tubal ectopic pregnancy on ultrasonography throughout. The second EP case was found at the hepatic region due to intermittent pain rising from the right upper quadrant region and serial ultrasonic findings. In our management, both cases were successfully assessed by laparoscopy and laparotomy without requiring further intervention, respectively. CLINICAL DISCUSSION: An accurate diagnosis of EP location at liver and pelvic wall is totally difficult since its uncommon location. An initial assessment should be based on clinical symptoms and the treatment remains controversial. The surgical management including laparotomy and laparoscopy depends on clinical evaluation, experience of surgeon, and interdisciplinary team. Thus, these abnormal sites of ectopic pregnancy ought to take into consideration for all gynecologists in an emergency condition with a major hemorrhage. CONCLUSIONS: In reproductive age women, primary EP at liver and pelvic wall should be considered with high index of suspicion if intrauterine pregnancy is totally excluded. Timely diagnosis, rational management by surgical excision, and a multidisciplinary team can reduce substantially adverse outcomes.

14.
Medicine (Baltimore) ; 103(17): e38000, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38669370

RESUMEN

This study aimed to assess the clinical utility of blood lactate-to-bicarbonate (L/B) ratio, as a prognostic factor for 28-day in-hospital mortality in children with dengue shock syndrome (DSS), admitted to the pediatric intensive care unit (PICU). This single-center retrospective study was conducted at a tertiary children hospital in southern Vietnam from 2013 to mid-2022. Prognostic models for DSS mortality were developed, using a predefined set of covariates in the first 24 hours of PICU admission. Area under the curves (AUCs), multivariable logistic and Least Absolute Shrinkage and Selection Operator (LASSO) regressions, bootstrapping and calibration slope were performed. A total of 492 children with DSS and complete clinical and biomarker data were included in the analysis, and 26 (5.3%) patients died. The predictive values for DSS mortality, regarding lactate showing AUC 0.876 (95% CI, 0.807-0.944), and that of L/B ratio 0.867 (95% CI, 0.80-0.934) (P values of both biomarkers < .001). The optimal cutoff point of the L/B ratio was 0.25, while that of lactate was 4.2 mmol/L. The multivariable model showed significant clinical predictors of DSS fatality including severe bleeding, cumulative amount of fluid infused and vasoactive-inotropic score (>30) in the first 24 hours of PICU admission. Combined with the identified clinical predictors, the L/B ratio yielded higher prognostic values (odds ratio [OR] = 8.66, 95% confidence interval [CI], 1.96-38.3; P < .01) than the lactate-based model (OR = 1.35, 95% CI, 1.15-1.58; P < .001). Both the L/B and lactate models showed similarly good performances. Considering that the L/B ratio has a better prognostic value than the lactate model, it may be considered a potential prognostic biomarker in clinical use for predicting 28-day mortality in PICU-admitted children with DSS.


Asunto(s)
Bicarbonatos , Biomarcadores , Mortalidad Hospitalaria , Unidades de Cuidado Intensivo Pediátrico , Ácido Láctico , Dengue Grave , Humanos , Masculino , Femenino , Estudios Retrospectivos , Pronóstico , Ácido Láctico/sangre , Dengue Grave/sangre , Dengue Grave/mortalidad , Dengue Grave/diagnóstico , Niño , Preescolar , Biomarcadores/sangre , Bicarbonatos/sangre , Unidades de Cuidado Intensivo Pediátrico/estadística & datos numéricos , Vietnam/epidemiología , Valor Predictivo de las Pruebas , Lactante , Área Bajo la Curva
16.
Int J Surg Case Rep ; 116: 109450, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38428051

RESUMEN

INTRODUCTION: Renal cell carcinoma poses significant challenges in kidney diseases, particularly in the context of the T3 stage, where treatment strategies remain controversial. The utilization of laparoscopic partial nephrectomy, particularly in developing countries, has been restricted for such patients, primarily due to limited infrastructure and concerns about recurrence risk and long-term pathologic outcomes. PRESENTATION OF CASE: In this report, we present a case of a 64-year-old male diagnosed with T3aN0M0 renal cell carcinoma (RCC). Abdominal computed tomography revealed a 5.2 × 5.2 × 5.1 cm mass on the right upper part of the kidney with a possible thrombus in the superior renal polar vein. The patient underwent successful treatment with retroperitoneal laparoscopic partial nephrectomy (LPN), leading to the preservation of kidney function with <4 mL/min/1.73 m2 GFR reduced after one year postoperative (estimated GFR from 85 mL/min/1.73 m2 to 81.79 mL/min/1.73 m2). The patient was discharged after three days; no recurrence was observed during the follow-up. DISCUSSION: For stage T3a RCC, studies show that LPN induces comparable long-term outcomes to radical nephrectomy, with advantages such as preserved kidney function, reduced operative time, blood loss, and shorter hospital stays. However, due to infrastructure constraints and limited access to robotic-assisted surgery in our country, coupled with concerns about tumor recurrence, laparoscopic radical nephrectomy is predominantly employed for similar patients. Our case represents one of the very first cases in which we successfully treated a patient diagnosed with T3a RCC using retroperitoneal laparoscopic partial nephrectomy. CONCLUSION: Laparoscopic partial nephrectomy is a reliable choice for T3aN0M0 RCC with good long-term outcomes and preserved renal function, especially by the hands of an experienced laparoscopic surgeon.

17.
J Sleep Res ; : e14203, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38544356

RESUMEN

By design, tripolar concentric ring electrodes (TCRE) provide more focal brain activity signals than conventional electroencephalography (EEG) electrodes placed further apart. This study compared spectral characteristics and rates of data loss to noisy epochs with TCRE versus conventional EEG signals recorded during sleep. A total of 20 healthy sleepers (12 females; mean [standard deviation] age 27.8 [9.6] years) underwent a 9-h sleep study. Participants were set up for polysomnography recording with TCRE to assess brain activity from 18 sites and conventional electrodes for EEG, eyes, and muscle movement. A fast Fourier transform using multitaper-based estimation was applied in 5-s epochs to scored sleep. Odds ratios with Bonferroni-adjusted 95% confidence intervals were calculated to determine the proportional differences in the number of noisy epochs between electrode types. Relative power was compared in frequency bands throughout sleep. Linear mixed models showed significant main effects of signal type (p < 0.001) and sleep stage (p < 0.001) on relative spectral power in each power band, with lower relative spectral power across all stages in TCRE versus EEG in alpha, beta, sigma, and theta activity, and greater delta power in all stages. Scalp topography plots showed distinct beta activation in the right parietal lobe with TCRE versus EEG. EEG showed higher rates of noisy epochs compared to TCRE (1.3% versus 0.8%, p < 0.001). TCRE signals showed marked differences in brain activity compared to EEG, consistent with more focal measurements and region-specific differences during sleep. TCRE may be useful for evaluating regional differences in brain activity with reduced muscle artefact compared to conventional EEG.

18.
BMC Oral Health ; 24(1): 230, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38350906

RESUMEN

BACKGROUND: The present study aimed to evaluate the effectiveness of using platelet-rich fibrin (PRF) as the apical matrix for the placement of MTA in nonsurgical endodontic therapy for teeth with periapical lesions and open apices. METHODS: Twelve teeth from eleven patients with periapical periodontitis and open apices were enrolled in the study. Nonsurgical endodontic therapy was performed with the PRF used as an apical barrier and the MTA manipulated as an apical plug for further thermoplasticized gutta percha in the remaining part of the root canal. Clinical signs and periapical digital radiographs were recorded and analyzed to evaluate the curing progress after periodical follow-ups of 1, 3, and 6 months. The horizontal dimension of the periapical lesion was determined, and the changes in the dimensions were recorded each time. The Friedman test was used for statistical analysis, with P < .05 serving as the threshold for determining statistical significance. RESULTS: All patients had no clinical symptoms after the first month of treatment, with a significant reduction in the periapical lesion after periodical appointments. CONCLUSIONS: PRF is an effective barrier when combined with MTA for the treatment of teeth with periapical periodontitis and open apices.


Asunto(s)
Periodontitis Periapical , Fibrina Rica en Plaquetas , Materiales de Obturación del Conducto Radicular , Humanos , Compuestos de Calcio/uso terapéutico , Materiales de Obturación del Conducto Radicular/uso terapéutico , Gutapercha/uso terapéutico , Periodontitis Periapical/terapia , Periodontitis Periapical/patología , Combinación de Medicamentos , Ápice del Diente/diagnóstico por imagen , Ápice del Diente/patología , Óxidos/uso terapéutico , Silicatos/uso terapéutico
19.
Heliyon ; 10(3): e25269, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38333803

RESUMEN

We present research on the role of multiple quantum well periods in extended short-wavelength infrared InGaAs/InAsPSb type-I LEDs. The fabricated LEDs consisted of 6, 15, and 30 quantum well periods, and we evaluated the structural properties and device performance through a combination of theoretical simulations and experimental characterization. The strain and energy band offset was precisely controlled by carefully adjusting the composition of the InAsPSb quaternary material, achieving high valence and conduction band offsets of 350 meV and 94 meV, respectively. Our LEDs demonstrated a high degree of relaxation of 94-96 %. Additionally, we discovered that the temperature-dependent dark current characterization attributed to generation-recombination and trap-assign tunneling, with trap-assign tunneling being more dominant at lower current injections. Electroluminescence analysis revealed that the predominant emission mechanism of the LEDs originated from localized exciton and free exciton radiative recombination, which the 30 quantum wells LED exhibited the highest contribution of the localized exciton/free exciton radiative recombination. We observed that increasing the quantum well periods from 6 to 15 led to an increase in the 300 K electroluminescence intensity of the LED. However, extending the quantum well period to 30 resulted in a decline in emission intensity due to the degradation of the epitaxial film quality.

20.
J Physiol ; 602(4): 597-617, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38345870

RESUMEN

Cardiac trabeculae are uneven ventricular muscular structures that develop during early embryonic heart development at the outer curvature of the ventricle. Their biomechanical function is not completely understood, and while their formation is known to be mechanosensitive, it is unclear whether ventricular tissue internal stresses play an important role in their formation. Here, we performed imaging and image-based cardiac biomechanics simulations on zebrafish embryonic ventricles to investigate these issues. Microscopy-based ventricular strain measurements show that the appearance of trabeculae coincided with enhanced deformability of the ventricular wall. Image-based biomechanical simulations reveal that the presence of trabeculae reduces ventricular tissue internal stresses, likely acting as structural support in response to the geometry of the ventricle. Passive ventricular pressure-loading experiments further reveal that the formation of trabeculae is associated with a spatial homogenization of ventricular tissue stiffnesses in healthy hearts, but gata1 morphants with a disrupted trabeculation process retain a spatial stiffness heterogeneity. Our findings thus suggest that modulating ventricular wall deformability, stresses, and stiffness are among the biomechanical functions of trabeculae. Further, experiments with gata1 morphants reveal that a reduction in fluid pressures and consequently ventricular tissue internal stresses can disrupt trabeculation, but a subsequent restoration of ventricular tissue internal stresses via vasopressin rescues trabeculation, demonstrating that tissue stresses are important to trabeculae formation. Overall, we find that tissue biomechanics is important to the formation and function of embryonic heart trabeculation. KEY POINTS: Trabeculations are fascinating and important cardiac structures and their abnormalities are linked to embryonic demise. However, their function in the heart and their mechanobiological formation processes are not completely understood. Our imaging and modelling show that tissue biomechanics is the key here. We find that trabeculations enhance cardiac wall deformability, reduce fluid pressure stresses, homogenize wall stiffness, and have alignments that are optimal for providing load-bearing structural support for the heart. We further discover that high ventricular tissue internal stresses consequent to high fluid pressures are needed for trabeculation formation through a rescue experiment, demonstrating that myocardial tissue stresses are as important as fluid flow wall shear stresses for trabeculation formation.


Asunto(s)
Miocitos Cardíacos , Pez Cebra , Animales , Fenómenos Biomecánicos , Transducción de Señal/fisiología , Miocardio , Corazón , Ventrículos Cardíacos
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