The RAS/BRAF/MEK/ERK mitogen-activated protein kinase (MAPK) pathway is emerging as a key modulator of melanoma initiation and progression. However, a variety of clinical studies indicate that ...inhibiting the MAPK pathway is insufficient per se to effectively kill melanoma cells. Here, we report on a genetic and pharmacologic approach to identify survival factors responsible for the resistance of melanoma cells to MEK/ERK antagonists. In addition, we describe a new tumor cell-selective means to bypass this resistance in vitro and in vivo. By generating a panel of isogenic cell lines with specific defects in the apoptotic machinery, we found that the ability of melanoma cells to survive in the absence of functional MEK relies on an ERK-independent expression of the antiapoptotic factor Mcl-1 (and to a lesser extent, Bcl-x(L) and Bcl-2). Using computer-based modeling, we developed a novel Bcl-2 homology domain 3 (BH3) mimetic. This compound, named TW-37, is the first rationally designed small molecule with high affinity for Mcl-1, Bcl-x(L), and Bcl-2. Mechanistic analyses of the mode of action of TW-37 showed a synergistic tumor cell killing in the presence of MEK inhibitors. Importantly, TW-37 unveiled an unexpected role of the MAPK pathway in the control of reactive oxygen species (ROS). This function was critical to prevent the activation of proapoptotic functions of p53 in melanoma cells, but surprisingly, it was dispensable for normal melanocytes. Our results suggest that this MAPK-dependent ROS/p53 feedback loop is a point of vulnerability of melanoma cells that can be exploited for rational drug design.
The aim of this study was to provide an evidence-based framework to guide health care professionals treating patients under glucocorticoid (GC) therapy and develop guidelines for the prevention and ...treatment of glucocorticoid-induced osteoporosis (GIO) in postmenopausal women and men aged ≥50 years.
An expert panel on bone diseases designed a series of clinically meaningful questions following the PICO (Population, Intervention, Comparator, and Outcome) structure. Using GRADE (Grading of Recommendations Assessment, Development, and Evaluation) methodology, we made a systematic literature review, extracted and summarized the effect estimates, and graded the quality of the evidence. The expert panel voted each PICO question and made recommendations after reaching an agreement of at least 70%.
Seventeen recommendations (9 strong and 8 conditional) and 8 general principles were developed for postmenopausal women and men aged ≥50 years under GC treatment. Bone mineral density (BMD), occurrence of fragility fractures, probability of fracture at 10 years by Fracture Risk Assessment Tool, and other screening factors for low BMD are recommended for patient evaluation and stratification according to fragility fracture risk. The treatment of patients under GC therapy should include counseling on lifestyle habits and strict control of comorbidities. The goal of GIO treatment is the nonoccurrence of new fragility fractures as well as to increase or maintain BMD in certain clinical situations. This was considered for the therapeutic approach in different clinical scenarios.
This GIO guideline provides evidence-based guidance for health care providers treating patients.
Diastolic function can be evaluated intraoperatively using transesoptiageal echocardiography.
To study if intraoperative diastolic dysfunction is associated to a greater number of hemodynamic events ...during surgery and during the postoperative period.
Patients with indication of intraoperative transesophageal echocardiography due to cardiovascular diseases were included in the study. Diastolic function was assessed measuring transmitral intraventricular filling delay and pulmonary vein now. Patients were divided, according to diastolic dysfunction, in those with derangements in relaxation, pseudonormalization and restrictive patterns. Hypertension, hypotension, ST segment depression, alterations in myocardial contractility, pulmonary congestion and postoperative oliguria were recorded.
Fifty eight patients aged 68+/- 12 years (39 males), were studied. Forty four had diastolic dysfunction. Intraoperative hypotension occurred in 82% of patients with diastolic dysfunction and 16% of patients without it. Likewise, hypotension and oliguria during the postoperative period were more common in patients with diastolic dysfunction.
In this group of patients with cardiovascular disease, intraoperative diastolic dysfunction is a risk factor for hemodynamic instability.
Introducción: conocer la seguridad de las drogas actualmente disponibles para el tratamiento de las enfermedades reumáticas es muy importante al momento de tomar decisiones terapéuticas objetivas e ...individualizadas en la consulta médica diaria. Asimismo, datos de la vida real amplían el conocimiento revelado por los ensayos clínicos.
Objetivos: describir los eventos adversos (EA) reportados, estimar su frecuencia e identificar los factores relacionados con su desarrollo.
Materiales y métodos: se utilizaron datos BIOBADASAR, un registro voluntario y prospectivo de seguimiento de EA de tratamientos biológicos y sintéticos dirigidos en pacientes con enfermedades reumáticas inmunomediadas. Los pacientes son seguidos hasta la muerte, pérdida de seguimiento o retiro del consentimiento informado. Para este análisis se extrajeron datos recopilados hasta el 31 de enero de 2023.
Resultados: se incluyó un total de 6253 pacientes, los cuales aportaron 9533 ciclos de tratamiento, incluyendo 3647 (38,3%) ciclos sin drogas modificadoras de la enfermedad biológicas y sintéticas dirigidas (DME-b/sd) y 5886 (61,7%) con DME-b/sd. Dentro de estos últimos, los más utilizados fueron los inhibidores de TNF y abatacept. Se reportaron 5890 EA en un total de 2701 tratamientos (844 y 1857 sin y con DME-b/sd, respectivamente), con una incidencia de 53,9 eventos cada 1000 pacientes/año (IC 95% 51,9-55,9). La misma fue mayor en los ciclos con DME-b/sd (71,1 eventos cada 1000 pacientes/año, IC 95% 70,7-77,5 versus 33,7, IC 95% 31,5-36,1; p<0,001). Las infecciones, particularmente las de la vía aérea superior, fueron los EA más frecuentes en ambos grupos. El 10,9% fue serio y el 1,1% provocó la muerte del paciente. El 18,7% de los ciclos con DME-b/sd fue discontinuado a causa de un EA, significativamente mayor a lo reportado en el otro grupo (11,5%; p<0,001). En el análisis ajustado, las DME-b/sd se asociaron a mayor riesgo de presentar al menos un EA (HR 1,82, IC 95% 1,64-1,96). De igual manera, la mayor edad, el mayor tiempo de evolución, el antecedente de enfermedad pulmonar obstructiva crónica, el diagnóstico de lupus eritematoso sistémico y el uso de corticoides se asociaron a mayor riesgo de EA.
Conclusiones: la incidencia de EA fue significativamente superior durante los ciclos de tratamientos que incluían DME-b/sd.
To analyse the characteristics and predictors of death in hospitalized patients with coronavirus disease 2019 (COVID-19) in Spain.
A retrospective observational study was performed of the first ...consecutive patients hospitalized with COVID-19 confirmed by real-time PCR assay in 127 Spanish centres until 17 March 2020. The follow-up censoring date was 17 April 2020. We collected demographic, clinical, laboratory, treatment and complications data. The primary endpoint was all-cause mortality. Univariable and multivariable Cox regression analyses were performed to identify factors associated with death.
Of the 4035 patients, male subjects accounted for 2433 (61.0%) of 3987, the median age was 70 years and 2539 (73.8%) of 3439 had one or more comorbidity. The most common symptoms were a history of fever, cough, malaise and dyspnoea. During hospitalization, 1255 (31.5%) of 3979 patients developed acute respiratory distress syndrome, 736 (18.5%) of 3988 were admitted to intensive care units and 619 (15.5%) of 3992 underwent mechanical ventilation. Virus- or host-targeted medications included lopinavir/ritonavir (2820/4005, 70.4%), hydroxychloroquine (2618/3995, 65.5%), interferon beta (1153/3950, 29.2%), corticosteroids (1109/3965, 28.0%) and tocilizumab (373/3951, 9.4%). Overall, 1131 (28%) of 4035 patients died. Mortality increased with age (85.6% occurring in older than 65 years). Seventeen factors were independently associated with an increased hazard of death, the strongest among them including advanced age, liver cirrhosis, low age-adjusted oxygen saturation, higher concentrations of C-reactive protein and lower estimated glomerular filtration rate.
Our findings provide comprehensive information about characteristics and complications of severe COVID-19, and may help clinicians identify patients at a higher risk of death.
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Objective
The objective of this study was to assess the SARS‐CoV‐2–specific humoral and T cell response after a two‐dose regimen of SARS‐CoV‐2 vaccine in patients with rheumatoid arthritis (RA).
...Methods
In this observational study, patients with RA who are ≥18 years of age and vaccinated for SARS‐CoV‐2 according to the Argentine National Health Ministry's vaccination strategy were included. Anti–SARS‐CoV‐2 immunoglobulin G (IgG) antibodies (ELISA‐COVIDAR test), neutralizing activity (cytotoxicity in VERO cells), and specific T cell response (IFN‐γ ELISpot Assay) were assessed after the first and second dose.
Results
A total of 120 patients with RA were included. Mostly, homologous regimens were used, including Gam‐COVID‐Vac (27.5%), ChAdOx1 (24.2%), and BBIBP‐CorV (22.5%). The most frequent combination was Gam‐COVID‐Vac/mRNA‐1273 (21.7%). After the second dose, 81.7% presented with anti–SARS‐CoV‐2 antibodies, 70.0% presented with neutralizing activity, and 65.3% presented with specific T cell response. The use of BBIBP‐CorV and treatment with abatacept (ABA) and rituximab (RTX) were associated with undetectable antibodies and no neutralizing activity after two doses. BBIBP‐CorV was also associated with the absence of T cell response. The total incidence of adverse events was 357.1 events per 1,000 doses, significantly lower with BBIBP‐CorV (166.7 events per 1,000 doses, P < 0.02).
Conclusion
In this RA cohort vaccinated with homologous and heterologous regimens against COVID‐19, 2 out of 10 patients did not develop anti‐SARS‐CoV‐2 IgG, 70% presented with neutralizing activity, and 65% presented with specific T cell response. The use of BBIBP‐CorV was associated with deficient humoral and cellular response, whereas treatment with ABA and RTX resulted in an impaired anti‐SARS‐CoV‐2 IgG formation and neutralizing activity.
Sperm capacitation is required for fertilization. At the molecular level, this process is associated with fast activation of protein kinase A. Downstream of this event, capacitating conditions lead ...to an increase in tyrosine phosphorylation. The identity of the tyrosine kinase(s) mediating this process has not been conclusively demonstrated. Recent experiments using stallion and human sperm have suggested a role for PYK2 based on the use of small molecule inhibitors directed against this kinase. However, crucially, loss-of-function experiments have not been reported. Here, we used both pharmacological inhibitors and genetically modified mice models to investigate the identity of the tyrosine kinase(s) mediating the increase in tyrosine phosphorylation in mouse sperm. Similar to stallion and human, PF431396 blocks the capacitation-associated increase in tyrosine phosphorylation. Yet, sperm from Pyk2(-/-) mice displayed a normal increase in tyrosine phosphorylation, implying that PYK2 is not responsible for this phosphorylation process. Here, we show that PF431396 can also inhibit FER, a tyrosine kinase known to be present in sperm. Sperm from mice targeted with a kinase-inactivating mutation in Fer failed to undergo capacitation-associated increases in tyrosine phosphorylation. Although these mice are fertile, their sperm displayed a reduced ability to fertilize metaphase II-arrested eggs in vitro.
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