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1.
JACC Case Rep ; 29(11): 102345, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38665998

RESUMEN

We report a case of a patient with a missed anterior myocardial infarction and associated ischemic cardiomyopathy. The patient had a massive true left ventricular aneurysm causing dynamic right ventricular compression, with associated cardiogenic shock, for which a heart transplantation was ultimately performed.

3.
J Perinat Med ; 52(3): 249-254, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38342778

RESUMEN

In June 2022, the Dobbs v. Jackson Women's Health Organization Supreme Court decision ended the constitutional right to the professional practice of abortion throughout the United States. The removal of the constitutional right to abortion has significantly altered the practice of obstetricians and gynecologists across the US. It potentially increases risks to pregnant patients, leads to profound changes in how physicians can provide care, especially in states with strict bans or gestational limits to abortion, and has introduced personal challenges, including moral distress and injury as well as legal risks for patients and clinicians alike. The professional responsibility model is based on the ethical concept of medicine as a profession and has been influential in shaping medical ethics in the field of obstetrics and gynecology. It provides the framework for the importance of ethical and professional conduct in obstetrics and gynecology. Viability marks a stage where the fetus is a patient with a claim to access to medical care. By allowing unrestricted abortions past this stage without adequate justifications, such as those concerning the life and health of the pregnant individual, or in instances of serious fetal anomalies, the states may not be upholding the equitable ethical consideration owed to the fetus as a patient. Using the professional responsibility model, we emphasize the need for nuanced, evidence-based policies that allow abortion management prior to viability without restrictions and allow abortion after viability to protect the pregnant patient's life and health, as well as permitting abortion for serious fetal anomalies.


Asunto(s)
Aborto Inducido , Mujeres Embarazadas , Embarazo , Femenino , Humanos , Estados Unidos , Viabilidad Fetal , Aborto Legal , Decisiones de la Corte Suprema
4.
Am J Obstet Gynecol ; 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37914062

RESUMEN

The landmark Roe vs Wade Supreme Court decision in 1973 established a constitutional right to abortion. In June 2022, the Dobbs vs Jackson Women's Health Organization Supreme Court decision brought an end to the established professional practice of abortion throughout the United States. Rights-based reductionism and zealotry threaten the professional practice of abortion. Rights-based reductionism is generally the view that moral or ethical issues can be reduced exclusively to matters of rights. In relation to abortion, there are 2 opposing forms of rights-based reductionism, namely fetal rights reductionism, which emphasizes the rights for the fetus while disregarding the rights and autonomy of the pregnant patient, and pregnant patient rights reductionism, which supports unlimited abortion without regards for the fetus. The 2 positions are irreconcilable. This article provides historical examples of the destructive nature of zealotry, which is characterized by extreme devotion to one's beliefs and an intolerant stance to opposing viewpoints, and of the importance of enlightenment to limit zealotry. This article then explores the professional responsibility model as a clinically ethically sound approach to overcome the clashing forms of rights-based reductionism and zealotry and to address the professional practice of abortion. The professional responsibility model refers to the ethical and professional obligations that obstetricians and other healthcare providers have toward pregnant patients, fetuses, and the society at large. It provides a more balanced and nuanced approach to the abortion debate, avoiding the pitfalls of reductionism and zealotry, and allows both the rights of the woman and the obligations to pregnant and fetal patients to be considered alongside broader ethical, medical, and societal implications. Constructive and respectful dialogue is crucial in addressing diverse perspectives and finding common ground. Embracing the professional responsibility model enables professionals to manage abortion responsibly, thereby prioritizing patients' interests and navigating between absolutist viewpoints to find balanced ethical solutions.

5.
bioRxiv ; 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37961198

RESUMEN

Hypertrophic cardiomyopathy is the most common cause of sudden death in the young. Because the disease exhibits variable penetrance, there are likely nongenetic factors that contribute to the manifestation of the disease phenotype. Clinically, hypertension is a major cause of morbidity and mortality in patients with HCM, suggesting a potential synergistic role for the sarcomeric mutations associated with HCM and mechanical stress on the heart. We developed an in vitro physiological model to investigate how the afterload that the heart muscle works against during contraction acts together with HCM-linked MYBPC3 mutations to trigger a disease phenotype. Micro-heart muscle arrays (µHM) were engineered from iPSC-derived cardiomyocytes bearing MYBPC3 loss-of-function mutations and challenged to contract against mechanical resistance with substrates stiffnesses ranging from the of embryonic hearts (0.4 kPa) up to the stiffness of fibrotic adult hearts (114 kPa). Whereas MYBPC3 +/- iPSC-cardiomyocytes showed little signs of disease pathology in standard 2D culture, µHMs that included components of afterload revealed several hallmarks of HCM, including cellular hypertrophy, impaired contractile energetics, and maladaptive calcium handling. Remarkably, we discovered changes in troponin C and T localization in the MYBPC3 +/- µHM that were entirely absent in 2D culture. Pharmacologic studies suggested that excessive Ca 2+ intake through membrane-embedded channels, rather than sarcoplasmic reticulum Ca 2+ ATPase (SERCA) dysfunction or Ca 2+ buffering at myofilaments underlie the observed electrophysiological abnormalities. These results illustrate the power of physiologically relevant engineered tissue models to study inherited disease mechanisms with iPSC technology.

6.
Horm Behav ; 156: 105449, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37922678

RESUMEN

The present study investigated the participation of the nitric oxide pathway in facilitating lordosis behavior induced by intrahypothalamic administration of apelin-13 in ovariectomized rats primed with estradiol benzoate (EB). The experiments involved the administration of a nitric oxide synthase inhibitor (L-NAME) or a nitric oxide-dependent, soluble guanylyl cyclase inhibitor (ODQ), and an inhibitor of protein kinase G (KT5823) to the ventromedial hypothalamus (VMH) of EB-primed rats 30 min before infusion of apelin-13 (0.75 µg/µl). This dose of apelin-13 consistently induces lordosis behavior at 30 min, 120 min, and 240 min following infusion. Results showed that injections of either L-NAME or KT5823 significantly reduced the lordosis induced by apelin at 120 and 240 min. However, VMH infusion of ODQ 30 min before apelin-13 infusion reduced but did not significantly inhibit, the lordosis elicited by this peptide at the same time points. We conclude that the nitric oxide pathway in the VMH plays an important role in lordosis induced by apelin-13 in EB-primed rats.


Asunto(s)
Lordosis , Óxido Nítrico , Ratas , Femenino , Animales , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico/metabolismo , Lordosis/inducido químicamente , Conducta Sexual Animal/fisiología , Estradiol/farmacología
8.
Biophys Rev (Melville) ; 4(1): 011315, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37034130

RESUMEN

In the field of cardiac electrophysiology, modeling has played a central role for many decades. However, even though the effort is well-established, it has recently seen a rapid and sustained evolution in the complexity and predictive power of the models being created. In particular, new approaches to modeling have allowed the tracking of parallel and interconnected processes that span from the nanometers and femtoseconds that determine ion channel gating to the centimeters and minutes needed to describe an arrhythmia. The connection between scales has brought unprecedented insight into cardiac arrhythmia mechanisms and drug therapies. This review focuses on the generation of these models from first principles, generation of detailed models to describe ion channel kinetics, algorithms to create and numerically solve kinetic models, and new approaches toward data gathering that parameterize these models. While we focus on application of these models for cardiac arrhythmia, these concepts are widely applicable to model the physiology and pathophysiology of any excitable cell.

9.
Semin Fetal Neonatal Med ; 28(3): 101441, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37121833

RESUMEN

A birth defect is a structural or chromosomal change present at birth that can affect almost any part or parts of the body. Birth defects can vary from mild to severe. On June 24, 2022, with its Dobbs v Jackson Women's Health Organization decision the Supreme Court of the United States overturned Roe v. Wade, removing the longstanding landmark 1973 ruling that secured a person's constitutional right to an abortion. With this decision individual states can now decide their own abortion laws. In about one-half of the states that continue the legality of pregnancy termination, the process of offering, discussing, and performing terminations of pregnancy remain the same as previously. In states where abortions are not legal, there will be conflicts between the law and the ethical responsibility of physicians to offer and discuss termination of pregnancy for severe anomalies.


Asunto(s)
Aborto Inducido , Aborto Legal , Embarazo , Recién Nacido , Femenino , Estados Unidos , Humanos , Consejo
10.
Int J Mol Sci ; 24(5)2023 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-36902486

RESUMEN

Oral mucositis is a common side effect of cancer treatment, and in particular of treatment with the mTORC1 inhibitor everolimus. Current treatment methods are not efficient enough and a better understanding of the causes and mechanisms behind oral mucositis is necessary to find potential therapeutic targets. Here, we treated an organotypic 3D oral mucosal tissue model consisting of human keratinocytes grown on top of human fibroblasts with a high or low dose of everolimus for 40 or 60 h and investigated (1) the effect of everolimus on microscopic sections of the 3D cell culture for evidence of morphologic changes and (2) changes in the transcriptome by high throughput RNA-Seq analysis. We show that the most affected pathways are cornification, cytokine expression, glycolysis, and cell proliferation and we provide further details. This study provides a good resource towards a better understanding of the development of oral mucositis. It gives a detailed overview of the different molecular pathways that are involved in mucositis. This in turn provides information about potential therapeutic targets, which is an important step towards preventing or managing this common side effect of cancer treatment.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Mucositis , Estomatitis , Humanos , Everolimus/farmacología , Transcriptoma , Estomatitis/etiología , Mucosa Bucal , Mucositis/inducido químicamente , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/complicaciones , Técnicas de Cultivo Tridimensional de Células
11.
Pharmaceuticals (Basel) ; 16(3)2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36986567

RESUMEN

The entry of proteins through the cell membrane is challenging, thus limiting their use as potential therapeutics. Seven cell-penetrating peptides, designed in our laboratory, were evaluated for the delivery of proteins. Fmoc solid-phase peptide synthesis was utilized for the synthesis of seven cyclic or hybrid cyclic-linear amphiphilic peptides composed of hydrophobic (tryptophan (W) or 3,3-diphenylalanine (Dip) and positively-charged arginine (R) residues, such as [WR]4, [WR]9, [WWRR]4, [WWRR]5, [(RW)5K](RW)5, [R5K]W7, and [DipR]5. Confocal microscopy was used to screen the peptides as a protein delivery system of model cargo proteins, green and red fluorescein proteins (GFP and RFP). Based on the confocal microscopy results, [WR]9 and [DipR]5 were found to be more efficient among all the peptides and were selected for further studies. [WR]9 (1-10 µM) + protein (GFP and RFP) physical mixture did not show high cytotoxicity (>90% viability) in triple-negative breast cancer cells (MDA-MB-231) after 24 h, while [DipR]5 (1-10 µM) physical mixture with GFP exhibited more than 81% cell viability. Confocal microscopy images revealed internalization of GFP and RFP in MDA-MB-231 cells using [WR]9 (2-10 µM) and [DipR]5 (1-10 µM). Fluorescence-activated cell sorting (FACS) analysis indicated that the cellular uptake of GFP was concentration-dependent in the presence of [WR]9 in MDA-MB-231 cells after 3 h of incubation at 37 °C. The concentration-dependent uptake of GFP and RFP was also observed in the presence of [DipR5] in SK-OV-3 and MDA-MB-231 cells after 3 h of incubation at 37 °C. FACS analysis indicated that the cellular uptake of GFP in the presence of [WR]9 was partially decreased by methyl-ß-cyclodextrin and nystatin as endocytosis inhibitors after 3 h of incubation in MDA-MB-231 cells, whereas nystatin and chlorpromazine as endocytosis inhibitors slightly reduced the uptake of GFP in the presence of [DipR]5 after 3 h of incubation in MDA-MB-231. [WR]9 was able to deliver therapeutically relevant proteins (Histone H2A) at different concentrations. These results provide insight into the use of amphiphilic cyclic peptides in the delivery of protein-related therapeutics.

12.
Artículo en Inglés | MEDLINE | ID: mdl-36721428

RESUMEN

Background: Phonotimpus pennimani (Araneae, Phrurolithidae) is a small-sized (3-5 mm) spider endemic to the Tacaná volcano in Chiapas, Mexico, where it is found in soil litter of cloud forests and coffee plantations. Its venom composition has so far not been investigated, partly because it is not a species of medical significance. However, it does have an important impact on the arthropod populations of its natural habitat. Methods: Specimens were collected in Southeastern Mexico (Chiapas) and identified taxonomically by morphological characteristics. A partial sequence from the mitochondrial gene coxI was amplified. Sequencing on the Illumina platform of a transcriptome library constructed from 12 adult specimens revealed 25 toxin or toxin-like genes. Transcripts were validated (RT-qPCR) by assessing the differential expression of the toxin-like PpenTox1 transcript and normalising with housekeeping genes. Results: Analysis of the coxI-gene revealed a similarity to other species of the family Phrurolithidae. Transcriptome analysis also revealed similarity with venom components of species from the families Ctenidae, Lycosidae, and Sicariidae. Expression of the toxin-like PpenTox1 gene was different for each developmental stage (juvenile or adult) and also for both sexes (female or male). Additionally, a partial sequence was obtained for the toxin-like PpenTox1 from DNA. Conclusion: Data from the amplification of the mitochondrial coxI gene confirmed that P. pennimani belongs to the family Phrurolithidae. New genes and transcripts coding for venom components were identified.

13.
Mol Pharm ; 20(1): 341-356, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36445335

RESUMEN

Cell-impermeable and negatively charged compounds' cellular uptake across the cell membranes remains challenging. Herein, the synthesis of four linear [(WWRR)2, (WWRR)3, (WWRR)4, and (WWRR)5] and four cyclic ([WWRR]2, [WWRR]3, [WWRR]4, and [WWRR]5) peptides containing alternate two tryptophan (WW) and two arginine (RR) residues and their biological evaluation as molecular transporters are reported. The peptides did not show any significant cytotoxicity in different cell lines (MDA-MB-23, SK-OV-3, and HEK 293) at a concentration of 5 µM and after 3 h of incubation time. The uptake of fluorescence-labeled cargo molecules (F'-GpYEEI, F'-siRNA, and F'-3TC) in the presence of the peptides was monitored in different cell lines (SK-OV-3 and MDA-MB-231) with fluorescence-activated cell sorting. Among all the peptides, [WWRR]5 (C4) showed the highest cellular uptake of cargo molecules, indicating it can act as effective molecular transporter. Confocal microscopy in MDA-MB-231 cells showed the cellular uptake of F'-GpYEEI in the presence of C4 and the intracellular localization of fluorescence-labeled C4 (F'-C4) in the cytosol. The F'-C4 cellular uptake was found to be concentration- and time-dependent, as shown by flow cytometry in MDA-MB-231 cells. Confocal microscopy and flow cytometry of F'-C4 in MDA-MB-231 cells were examined alone and in the presence of different endocytosis inhibitors (chlorpromazine, methyl-ß-cyclodextrin, chloroquine, and nystatin). The data showed that the cellular uptake of F'-C4 in the presence of chlorpromazine, chloroquine, and methyl-ß-cyclodextrin was reduced but not completely eliminated, indicating that both energy-independent and energy-dependent pathways contributed to the cellular uptake of F'-C4. Similar results were obtained using the confocal microscopy of C4 and F'-GpYEEI in the presence of endocytosis inhibitors (chlorpromazine, methyl-ß-cyclodextrin, chloroquine, and nystatin). These data indicate that C4 has the potential to be used as a cell-penetrating peptide and cargo transporter.


Asunto(s)
Péptidos de Penetración Celular , Péptidos Cíclicos , Humanos , Péptidos Cíclicos/química , Clorpromazina , Células HEK293 , Nistatina , Línea Celular Tumoral , Endocitosis
14.
Rev. bras. psicodrama ; 31: e0923, 2023.
Artículo en Inglés | LILACS-Express | LILACS, Index Psicología - Revistas | ID: biblio-1431677
15.
bioRxiv ; 2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38187680

RESUMEN

The resurgent sodium current (INaR) activates on membrane repolarization, such as during the downstroke of neuronal action potentials. Due to its unique activation properties, INaR is thought to drive high rates of repetitive neuronal firing. However, INaR is often studied in combination with the persistent or non-inactivating portion of sodium currents (INaP). We used dynamic clamp to test how INaR and INaP individually affect repetitive firing in adult cerebellar Purkinje neurons. We learned INaR does not scale repetitive firing rates due to its rapid decay at subthreshold voltages, and that subthreshold INaP is critical in regulating neuronal firing rate. Adjustments to the Nav conductance model used in these studies revealed INaP and INaR can be inversely scaled by adjusting occupancy in the slow inactivated kinetic state. Together with additional dynamic clamp experiments, these data suggest the regulation of sodium channel slow inactivation can fine-tune INaP and Purkinje neuron repetitive firing rates.

16.
Ethics Hum Res ; 44(6): 39-42, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36098232

RESUMEN

The Russian invasion of Ukraine has led to the imposition of economic sanctions intended to isolate Russia from much of global commerce, which implicitly includes the medical research enterprise. The prospect of ongoing isolation of Russia's substantial research enterprise raises issues related to but distinct from the more familiar problem of corruption. In this paper, we identify reasons that the culture of research ethics in Russia may have been weak even before the war, contributing to hard questions about its future role in the global clinical research community.


Asunto(s)
Comercio , Ética en Investigación , Humanos , Federación de Rusia , Ucrania
17.
Front Big Data ; 5: 978734, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36156934

RESUMEN

The military applications of AI raise myriad ethical challenges. Critical among them is how AI integrates with human decision making to enhance cognitive performance on the battlefield. AI applications range from augmented reality devices to assist learning and improve training to implantable Brain-Computer Interfaces (BCI) to create bionic "super soldiers." As these technologies mature, AI-wired warfighters face potential affronts to cognitive liberty, psychological and physiological health risks and obstacles to integrating into military and civil society during their service and upon discharge. Before coming online and operational, however, AI-assisted technologies and neural interfaces require extensive research and human experimentation. Each endeavor raises additional ethical concerns that have been historically ignored thereby leaving military and medical scientists without a cogent ethics protocol for sustainable research. In this way, this paper is a "prequel" to the current debate over enhancement which largely considers neuro-technologies once they are already out the door and operational. To lay the ethics foundation for AI-assisted warfighter enhancement research, we present an historical overview of its technological development followed by a presentation of salient ethics research issues (ICRC, 2006). We begin with a historical survey of AI neuro-enhancement research highlighting the ethics lacunae of its development. We demonstrate the unique ethical problems posed by the convergence of several technologies in the military research setting. Then we address these deficiencies by emphasizing how AI-assisted warfighter enhancement research must pay particular attention to military necessity, and the medical and military cost-benefit tradeoffs of emerging technologies, all attending to the unique status of warfighters as experimental subjects. Finally, our focus is the enhancement of friendly or compatriot warfighters and not, as others have focused, enhancements intended to pacify enemy warfighters.

18.
Perspect Biol Med ; 65(3): 426-441, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36093775

RESUMEN

Over the last 80 years, a series of critical events has led to reconsideration of the basic premises of medical ethics. One of these events was the recognition of horrific medical experiments performed by German medical scientists in World War II concentration camps, resulting in intensified emphasis on a consent requirement, later understood as grounded in the bioethical principle of respect for autonomy, as well as on the moral accountability of the experimenter. Another important event that is forcing a reconsideration of respect for autonomy in medicine and health care is the COVID-19 pandemic. But this time the matter pulls in a different direction, from respect for autonomy to social responsibility, represented in problems as disparate as the wearing of masks, vaccination requirements, and equity in vaccine access and distribution. How can modern bioethics, in part a creature of the response to Nazi crimes, accommodate the intensified sensitivity about public health needs that has accompanied the shock of the pandemic? The responses of European medical ethics to the Nazi era provide tools for bioethics as it faces the challenge now at hand. This article uses historical context from postwar Europe to argue that, in light of the pandemic experience, respect for autonomy must systematically incorporate a commitment to social responsibility.


Asunto(s)
Bioética , COVID-19 , COVID-19/epidemiología , Ética Médica , Humanos , Pandemias , Responsabilidad Social
19.
Tissue Eng Part C Methods ; 28(9): 457-468, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35925789

RESUMEN

Drugs are often removed from clinical trials or market progression owing to their unforeseen effects on cardiac action potential and calcium handling. Induced pluripotent stem cell-derived cardiomyocytes and tissues fabricated from these cells are promising as screening tools for early identification of these potential cardiac liabilities. In this study, we describe an automated, open-source MATLAB-based analysis software for calculating cardiac action potentials and calcium transients from fluorescent reporters. We first identified the most robust manner in which to automatically identify the initiation point for action potentials and calcium transients in a user-independent manner, and used this approach to quantify the duration and morphology of these signals. We then demonstrate the software by assessing changes to action potentials and calcium transients in our micro-heart muscles after exposure to hydroxychloroquine, an antimalarial drug with known cardiac liability. Consistent with clinical observations, our system predicted mild action potential prolongation. However, we also observed marked calcium transient suppression, highlighting the advantage of testing multiple physiologic readouts in cardiomyocytes rather than relying on heterologous overexpression of single channels such as the human ether-a-go-go-related gene channel. This open-source software can serve as a useful, high-throughput tool for analyzing cardiomyocyte physiology from fluorescence imaging.


Asunto(s)
Antimaláricos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Células Madre Pluripotentes Inducidas , Antimaláricos/farmacología , Calcio , Electrofisiología , Éteres/farmacología , Humanos , Hidroxicloroquina/farmacología , Miocitos Cardíacos
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