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2.
Neural Netw ; 170: 506-520, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38043371

RESUMO

The objective of this study is to investigate the synchronization criteria under the sampled-data control method for multi-agent systems (MASs) with state quantization and time-varying delay. Currently, a looped Lyapunov-Krasovskii Functional (LKF) has been developed, which integrates information from the sampling interval to ensure that the leader system synchronizes with the follower system, resulting in a specific condition in the form of Linear Matrix Inequalities (LMIs). The LMIs can be easily solved using the LMI Control toolbox in Matlab. Finally, the proposed approach's feasibility and effectiveness are demonstrated through numerical simulations and comparative results.


Assuntos
Redes Neurais de Computação , Fatores de Tempo
3.
Entropy (Basel) ; 25(8)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37628175

RESUMO

The general delay Hopfield neural network is studied. We consider the case of time-varying delay, continuously distributed delays, time-varying coefficients, and a special type of a Riemann-Liouville fractional derivative (GRLFD) with an exponential kernel. The kernels of the fractional integral and the fractional derivative in this paper are Sonine kernels and satisfy the first and the second fundamental theorems in calculus. The presence of delays and GRLFD in the model require a special type of initial condition. The applied GRLFD also requires a special definition of the equilibrium of the model. A constant equilibrium of the model is defined. An inequality for Lyapunov type of convex functions with the applied GRLFD is proved. It is combined with the Razumikhin method to study stability properties of the equilibrium of the model. As a partial case we apply quadratic Lyapunov functions. We prove some comparison results for Lyapunov function connected deeply with the applied GRLFD and use them to obtain exponential bounds of the solutions. These bounds are satisfied for intervals excluding the initial time. Also, the convergence of any solution of the model to the equilibrium at infinity is proved. An example illustrating the importance of our theoretical results is also included.

4.
Ann Pediatr Cardiol ; 16(1): 4-10, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37287843

RESUMO

Background: Junctional ectopic tachycardia (JET) is the most common arrhythmia after pediatric open-heart surgeries (OHS), causing high morbidity and mortality. As diagnosis is often missed in patients with minimal hemodynamic instability, its incidence depends on active surveillance. A prospective randomized trial evaluated the efficacy and safety of prophylactic amiodarone and dexmedetomidine to prevent and control postoperative JET. Methods: Consecutive patients aged under 12 years were randomized into amiodarone, dexmedetomidine (initiated during anesthetic induction) and control groups. Outcome measures included incidence of JET, inotropic score, ventilation, and intensive care unit (ICU) duration and hospital stay, as well as adverse drug effects. Results: Two hundred and twenty-five consecutive patients with a median age of 9 months (range 2 days-144 months) and a median weight of 6.3 kg (range 1.8 kg-38 kg) were randomized with 70 patients each to amiodarone and dexmedetomidine groups, and the rest were controls. Ventricular septal defect and Fallot's tetralogy were the common defects. The overall incidence of JET was 16.4%. Syndromic patients, hypokalemia, hypomagnesemia, longer bypass, and cross-clamp duration were the risk factors for JET. Patients with JET had significantly prolonged ventilation (P = 0.043), longer ICU (P = 0.004), and hospital stay (P = 0.034) than those without JET. JET was less frequent in amiodarone (8.5%) and dexmedetomidine (14.2%) groups compared to controls (24.7%) (P = 0.022). Patients receiving amiodarone and dexmedetomidine had significantly lower inotropic requirements, lower ventilation duration (P = 0.008), ICU (P = 0.006), and hospital stay (P = 0.05). Adverse effects such as bradycardia and hypotension after amiodarone and ventricular dysfunction after dexmedetomidine were not significantly different from controls. Conclusion: Prophylactic amiodarone or dexmedetomidine started before OHS is effective and safe for the prevention of postoperative JET.

5.
Expert Rev Anticancer Ther ; 23(4): 385-395, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36944434

RESUMO

INTRODUCTION: Most patients diagnosed with endometrial hyperplasia or cancer are obese. Obesity, along with polycystic ovarian syndrome (PCOS) and type-2 diabetes mellitus (T2DM), may act synergistically to increase risk of malignant endometrial pathology. Incidence of malignant endometrial pathology is increasing, particularly in reproductive aged women. In patients who desire future fertility, the levonorgestrel intrauterine device (LNG-IUD) is often utilized. If the first-line progestin therapy fails, there is not an effective second-line adjunct option. Moreover, pregnancy rates following fertility-sparing treatment are lower-than-expected in these patients. AREAS COVERED: This clinical opinion provides a summary of recent studies exploring risk factors for the development of malignant endometrial pathology including obesity, PCOS, and T2DM. Studies assessing efficacy of fertility-sparing treatment of malignant endometrial pathology are reviewed, and a potential new adjunct treatment approach to LNG-IUD is explored. EXPERT OPINION: There is an unmet-need for a personalized treatment approach in cases of first-line progestin treatment failure. Glucagon-like peptide 1 receptor agonists are a class of anti-diabetic agents, but may have a role in fertility-sparing treatment of obese patients with malignant endometrial pathology by reducing weight, decreasing inflammation, and decreasing insulin resistance; these changes may also improve chances of subsequent pregnancy. This hypothesis warrants further exploration.


Assuntos
Diabetes Mellitus Tipo 2 , Neoplasias do Endométrio , Preservação da Fertilidade , Síndrome do Ovário Policístico , Gravidez , Humanos , Feminino , Adulto , Progestinas/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1/uso terapêutico , Levanogestrel/efeitos adversos , Obesidade/complicações , Obesidade/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/induzido quimicamente , Neoplasias do Endométrio/tratamento farmacológico
6.
F S Rep ; 4(4): 375-379, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38204947

RESUMO

Objective: To compare the consistency of endometrial receptivity array (ERA) and histologic dating among 3 spatially distinct endometrial samples obtained during a cycle of exogenous estrogen and progesterone. Design: Prospective blinded study. Setting: University practice. Patients: Twelve patients undergoing a mock frozen embryo transfer cycle. Intervention: Endometrial biopsy was performed in a manner that provided a spatially organized endometrial specimen, corresponding to the fundus, middle, and lower segment. Each of these 3 sections was further divided into immediately adjacent specimens for ERA and histology. Main Outcome Measure: Consistency of the ERA and histology results among fundal, mid, and lower endometrial biopsy specimens. Results: The ERA showed variability in outcome among different patients but dated all specimens originating from the same patient identically. Histologic dating showed variability between patients as well as between different locations within the uterus. When comparing average dating results for each patient, we saw a positive correlation between histologic and ERA dating (Spearman Rho = 0.45); however, this did not reach statistical significance. The ERA results from upper, mid, and lower uterine biopsy specimens were identical for each autologous biopsy, whereas histologic dating showed variability with an average standard deviation of 0.71 days. Conclusions: The increased heterogeneity of histologic dating is likely to be attributed to the subjectivity of the test. Furthermore, we did not observe a consistent lag or advancement in histologic or ERA dating between the fundal or lower uterine biopsies. Overall, clinicians should be reassured that endometrial tissue will return consistent ERA results independent of the location within the uterus in which it was obtained.

7.
Cell Stem Cell ; 29(12): 1637-1652.e6, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36459967

RESUMO

The concept of senescence as a phenomenon limited to proliferating cells has been challenged by growing evidence of senescence-like features in terminally differentiated cells, including neurons. The persistence of senescent cells late in life is associated with tissue dysfunction and increased risk of age-related disease. We found that Alzheimer's disease (AD) brains have significantly higher proportions of neurons that express senescence markers, and their distribution indicates bystander effects. AD patient-derived directly induced neurons (iNs) exhibit strong transcriptomic, epigenetic, and molecular biomarker signatures, indicating a specific human neuronal senescence-like state. AD iN single-cell transcriptomics revealed that senescent-like neurons face oncogenic challenges and metabolic dysfunction as well as display a pro-inflammatory signature. Integrative profiling of the inflammatory secretome of AD iNs and patient cerebral spinal fluid revealed a neuronal senescence-associated secretory phenotype that could trigger astrogliosis in human astrocytes. Finally, we show that targeting senescence-like neurons with senotherapeutics could be a strategy for preventing or treating AD.


Assuntos
Doença de Alzheimer , Humanos , Idoso , Neurônios , Astrócitos , Oncogenes , Encéfalo
8.
Cell Metab ; 34(9): 1248-1263.e6, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35987203

RESUMO

The drivers of sporadic Alzheimer's disease (AD) remain incompletely understood. Utilizing directly converted induced neurons (iNs) from AD-patient-derived fibroblasts, we identified a metabolic switch to aerobic glycolysis in AD iNs. Pathological isoform switching of the glycolytic enzyme pyruvate kinase M (PKM) toward the cancer-associated PKM2 isoform conferred metabolic and transcriptional changes in AD iNs. These alterations occurred via PKM2's lack of metabolic activity and via nuclear translocation and association with STAT3 and HIF1α to promote neuronal fate loss and vulnerability. Chemical modulation of PKM2 prevented nuclear translocation, restored a mature neuronal metabolism, reversed AD-specific gene expression changes, and re-activated neuronal resilience against cell death.


Assuntos
Doença de Alzheimer , Neoplasias , Glicólise , Humanos , Neoplasias/patologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Piruvato Quinase/genética , Piruvato Quinase/metabolismo
9.
Arch Gynecol Obstet ; 306(4): 1321-1327, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35821525

RESUMO

PURPOSE: To determine if blastocyst trophectoderm biopsy for PGT-A is associated with an increased rate of live birth per embryo in good prognosis IVF patients at a single center. METHODS: We performed a retrospective cohort study of good prognosis embryo transfer cycles at a single center from 1/1/2017 to 12/31/2019. We evaluated the rate of live birth per embryo with and without PGT-A for transfer of embryos in two groups of good prognosis patients: embryos from donor oocytes and embryos from autologous oocytes with maternal age less than 35 years at oocyte retrieval. Two-sided Fisher's exact tests were used for comparisons between groups. RESULTS: After transfer of embryos created from donor oocytes the live birth rate per euploid embryo was 70.6% (24/34) compared to 34.3% (35/102) for untested embryos for a rate difference of 36.3% (95% CI 18.4-54.1%, p < 0.01). After transfer of embryos created from autologous oocytes with maternal age less than 35 years at oocyte retrieval the live birth rate per euploid embryo was 70.0% (49/70) compared to 52.5% (53/101) for untested embryos for a rate difference of 17.5% (95% CI 3.0-32.0%, p = 0.03). CONCLUSIONS: In good prognosis patients at our center the live birth rate per euploid blastocyst was higher than for untested blastocysts.


Assuntos
Coeficiente de Natalidade , Diagnóstico Pré-Implantação , Aneuploidia , Biópsia , Blastocisto/patologia , Feminino , Fertilização in vitro , Humanos , Nascido Vivo , Gravidez , Prognóstico , Estudos Retrospectivos
10.
Exp Neurol ; 355: 114124, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35644426

RESUMO

Within the adult central nervous system (CNS) of most mammals resides a resident stem cell population, known as neural stem cells (NSCs). NSCs are located within specific niches of the CNS and maintain a self-renewal and proliferative capacity to generate new neurons, astrocytes, and oligodendrocytes throughout adulthood. The NSC niches are dynamic and active environments that are within proximity to the systemic circulation and the cerebrospinal fluid (CSF). Therefore, NSCs respond not only to factors present in the local microenvironment of the niche but also to factors present in the systemic macroenvironment. The factors can be soluble forms such as cytokines and chemokines located in the circulation or directly from local cells, such as microglia and astrocytes. Additionally, recent evidence points towards physiological aging and its association with a progressive loss of function and a decline in the self-renewal and regenerative capacities of CNS NSCs, which can be further exacerbated by changes in the local and systemic milieu. This review will highlight the main intrinsic and extrinsic regulators of neural stem cell function under homeostatic and inflammatory conditions including those trafficked within extracellular membrane vesicles. Further, discussion will center around how intrinsic and extrinsic factors impact normal homeostatic functions within the adult brain and in aging.


Assuntos
Células-Tronco Neurais , Neurogênese , Animais , Encéfalo , Diferenciação Celular , Inflamação/metabolismo , Mamíferos , Células-Tronco Neurais/metabolismo , Neurogênese/fisiologia , Nicho de Células-Tronco/fisiologia
11.
Gene ; 831: 146561, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35561845

RESUMO

Virus infection alters host gene expression, therefore ideal and stable reference housekeeping genes are required to normalise the expression of other expressed host genes in quantitative real-time PCR (qRT-PCR). The suitable reference gene may vary in response to different viral infections in different hosts or cells. In the present study, we cultured primary lamb testis cells (LTC) and assessed the expression stability of seven widely used housekeeping genes (B2M, HMBS, HPRT1, HSP-90, POLR2A, 18s_RNA, GAPDH) as reference genes in Sheeppox virus (SPPV) infected and control (uninfected-0h) LTC at 0.5h, 4.0h, 8.0h, and 12.0h post-infection) using NormFinder, Bestkeeper, geNorm, and the comparative ΔCT method in RefFinder based on their expression levels. Analysis revealed that HSP90, 18s_RNA, HPRT, POLR2A, and B2M were the most stable genes from the panel in the individual analysis group in 0h, 0.5h, 4.0h, 8.0h, and 12.0h, respectively. Furthermore, B2M was shown to be the most stable reference gene in the combined control with the respective and overall infected groups, except the control group of 4.0hpi of SPPV infection. In this study, we selected the most suitable reference genes in LTC for particular time points of SPPV infection. The identified most suitable housekeeping gene can be used during normalization of expression of other targeted genes at aspecific time point of SPPV infection.


Assuntos
Capripoxvirus , Perfilação da Expressão Gênica , Animais , Expressão Gênica , Perfilação da Expressão Gênica/métodos , Masculino , RNA Ribossômico 18S , Reação em Cadeia da Polimerase em Tempo Real/métodos , Padrões de Referência , Ovinos/genética , Testículo
12.
Entropy (Basel) ; 24(3)2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35327883

RESUMO

A model of gene regulatory networks with generalized proportional Caputo fractional derivatives is set up, and stability properties are studied. Initially, some properties of absolute value Lyapunov functions and quadratic Lyapunov functions are discussed, and also, their application to fractional order systems and the advantage of quadratic functions are pointed out. The equilibrium of the generalized proportional Caputo fractional model and its generalized exponential stability are defined, and sufficient conditions for the generalized exponential stability and asymptotic stability of the equilibrium are obtained. As a special case, the stability of the equilibrium of the Caputo fractional model is discussed. Several examples are provided to illustrate our theoretical results and the influence of the type of fractional derivative on the stability behavior of the equilibrium.

13.
Asian Cardiovasc Thorac Ann ; 30(3): 335-338, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33789442

RESUMO

Absence of arterial duct, a sixth aortic arch derivative, plays an important etiologic role in Tetralogy of Fallot with absent pulmonary valve syndrome. When fetal ductus is absent, the large right ventricular stroke volume dilates the pulmonary trunk leading to pulmonary regurgitation. A proximal extension of the embryonic insult to the entire left sixth arch causes absence of the left pulmonary artery, a common association of absent pulmonary valve syndrome. On the contrary, absence of right pulmonary artery is not reported in absent pulmonary valve syndrome. A rare combination of tetralogy, absent pulmonary valve syndrome and isolation of a hypoplastic right pulmonary artery offered challenges to diagnosis and management.


Assuntos
Atresia Pulmonar , Valva Pulmonar , Tetralogia de Fallot , Humanos , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/cirurgia , Valva Pulmonar/diagnóstico por imagem , Valva Pulmonar/cirurgia , Tetralogia de Fallot/complicações , Tetralogia de Fallot/diagnóstico por imagem , Tetralogia de Fallot/cirurgia , Resultado do Tratamento
15.
BMC Pregnancy Childbirth ; 21(1): 651, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34560839

RESUMO

BACKGROUND: Diabetes Mellitus (DM) is a major cause of maternal, fetal, and neonatal morbidities. Our objective was to estimate the effect of both pre-pregnancy and gestational DM on the growth parameters of newborns in the Qatari population. METHODS: In this population-based cohort study, we compared the data of neonates born to Qatari women with both pre-pregnancy and gestational diabetes mellitus in 2017 with neonates of healthy non-diabetic Qatari women. RESULTS: Out of a total of 17020 live births in 2017, 5195 newborns were born to Qatari women. Of these, 1260 were born to women with GDM, 152 were born to women with pre-pregnancy DM and 3783 neonates were born to healthy non-diabetic (control) women. The prevalence of GDM in the Qatari population in 2017 was 24.25%. HbA1C% before delivery was significantly higher in women with pre-pregnancy DM (mean 6.19 ± 1.15) compared to those with GDM (mean 5.28 ± 0.43) (P <0.0001). The mean birth weight in grams was 3066.01 ± 603.42 in the control group compared to 3156.73 ± 577.88 in infants born to women with GDM and 3048.78 ± 677.98 in infants born to women with pre-pregnancy DM (P <0.0001). There was no statistically significant difference regarding the mean length (P= 0.080), head circumference (P= 0.514), and rate of major congenital malformations (P= 0.211). Macrosomia (Birth weight > 4000 gm) was observed in 2.7% of the control group compared to 4.8% in infants born to women with GDM, and 4.6% in infants born to women with pre-pregnancy DM (P= 0.001). Multivariate logistic regression analysis demonstrated that higher maternal age (adjusted OR 2.21, 95% CI 1.93, 2.52, P<0.0001), obesity before pregnancy (adjusted OR 1.71, 95% CI 1.30, 2.23, P<0.0001), type of delivery C-section (adjusted OR 1.25, 95% CI 1.09, 1.44, P=0.002), and body weight to gestational age LGA (adjusted OR 2.30, 95% CI 1.64, 2.34, P<0.0001) were significantly associated with increased risk of GDM. CONCLUSION: Despite the multi-disciplinary antenatal diabetic care management, there is still an increased birth weight and an increased prevalence of macrosomia among the infants of diabetic mothers. More efforts should be addressed to improve the known modifiable factors such as women's adherence to the diabetic control program. Furthermore, pre-pregnancy BMI was found to be significantly associated with gestational DM, and this is a factor that can be addressed during pre-conceptional counseling.


Assuntos
Diabetes Mellitus/epidemiologia , Diabetes Gestacional/epidemiologia , Recém-Nascido/crescimento & desenvolvimento , Gravidez em Diabéticas/epidemiologia , Adulto , Peso ao Nascer , Índice de Massa Corporal , Cesárea/estatística & dados numéricos , Estudos de Coortes , Anormalidades Congênitas/epidemiologia , Estudos Transversais , Feminino , Macrossomia Fetal/epidemiologia , Idade Gestacional , Hemoglobinas Glicadas , Humanos , Masculino , Idade Materna , Gravidez , Catar/epidemiologia , Estudos Retrospectivos
16.
Entropy (Basel) ; 23(7)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34356412

RESUMO

In this work, we establish some integral inequalities involving metrics. Moreover, some applications to partial metric spaces are given. Our results are extension of previous obtained metric inequalities in the discrete case.

17.
Entropy (Basel) ; 23(8)2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34441226

RESUMO

This research article is dedicated to solving fractional-order parabolic equations using an innovative analytical technique. The Adomian decomposition method is well supported by natural transform to establish closed form solutions for targeted problems. The procedure is simple, attractive and is preferred over other methods because it provides a closed form solution for the given problems. The solution graphs are plotted for both integer and fractional-order, which shows that the obtained results are in good contact with the exact solution of the problems. It is also observed that the solution of fractional-order problems are convergent to the solution of integer-order problem. In conclusion, the current technique is an accurate and straightforward approximate method that can be applied to solve other fractional-order partial differential equations.

18.
J Craniofac Surg ; 32(5): 1955-1965, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34319684

RESUMO

ABSTRACT: Conditions that affect dental and periodontal structures receive sparse coverage in the plastic surgery literature, yet a working knowledge of this subject matter is important in certain areas of clinical practice and a fundamental understanding is part of plastic surgery competency tested on the in-service and written board examinations. This 4-part series was written to provide plastic surgeons with a working knowledge of dental topics that may be relevant to their clinical practice. This section, Part IV, covers common dental cyst and tumors of the jaw.


Assuntos
Cistos , Neoplasias Maxilomandibulares , Procedimentos de Cirurgia Plástica , Cirurgiões , Cirurgia Plástica , Humanos , Neoplasias Maxilomandibulares/cirurgia
19.
Cell Stem Cell ; 28(9): 1533-1548.e6, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33910058

RESUMO

Sporadic Alzheimer's disease (AD) exclusively affects elderly people. Using direct conversion of AD patient fibroblasts into induced neurons (iNs), we generated an age-equivalent neuronal model. AD patient-derived iNs exhibit strong neuronal transcriptome signatures characterized by downregulation of mature neuronal properties and upregulation of immature and progenitor-like signaling pathways. Mapping iNs to longitudinal neuronal differentiation trajectory data demonstrated that AD iNs reflect a hypo-mature neuronal identity characterized by markers of stress, cell cycle, and de-differentiation. Epigenetic landscape profiling revealed an underlying aberrant neuronal state that shares similarities with malignant transformation and age-dependent epigenetic erosion. To probe for the involvement of aging, we generated rejuvenated iPSC-derived neurons that showed no significant disease-related transcriptome signatures, a feature that is consistent with epigenetic clock and brain ontogenesis mapping, which indicate that fibroblast-derived iNs more closely reflect old adult brain stages. Our findings identify AD-related neuronal changes as age-dependent cellular programs that impair neuronal identity.


Assuntos
Doença de Alzheimer , Células-Tronco Pluripotentes Induzidas , Idoso , Envelhecimento , Fibroblastos , Humanos , Neurônios
20.
Entropy (Basel) ; 23(4)2021 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-33920402

RESUMO

As an effective tool to unify discrete and continuous analysis, time scale calculus have been widely applied to study dynamic systems in both theoretical and practical aspects. In addition to such a classical role of unification, the dynamic equations on time scales have their own unique features which the difference and differential equations do not possess and these advantages have been highlighted in describing some complicated dynamical behavior in the hybrid time process. In this review article, we conduct a survey of abstract analysis and applied dynamic equations on hybrid time scales, some recent main results and the related developments on hybrid time scales will be reported and the future research related to this research field is discussed. The results presented in this article can be extended and generalized to study both pure mathematical analysis and real applications such as mathematical physics, biological dynamical models and neural networks, etc.

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