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1.
Cell ; 158(4): 705-721, 2014 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-25126780

RESUMEN

Acquisition of the intestinal microbiota begins at birth, and a stable microbial community develops from a succession of key organisms. Disruption of the microbiota during maturation by low-dose antibiotic exposure can alter host metabolism and adiposity. We now show that low-dose penicillin (LDP), delivered from birth, induces metabolic alterations and affects ileal expression of genes involved in immunity. LDP that is limited to early life transiently perturbs the microbiota, which is sufficient to induce sustained effects on body composition, indicating that microbiota interactions in infancy may be critical determinants of long-term host metabolic effects. In addition, LDP enhances the effect of high-fat diet induced obesity. The growth promotion phenotype is transferrable to germ-free hosts by LDP-selected microbiota, showing that the altered microbiota, not antibiotics per se, play a causal role. These studies characterize important variables in early-life microbe-host metabolic interaction and identify several taxa consistently linked with metabolic alterations. PAPERCLIP:


Asunto(s)
Antibacterianos/administración & dosificación , Modelos Animales de Enfermedad , Intestinos/microbiología , Microbiota , Obesidad/microbiología , Penicilinas/administración & dosificación , Animales , Bacterias/clasificación , Bacterias/metabolismo , Femenino , Mucosa Intestinal/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Microbiota/efectos de los fármacos , Obesidad/metabolismo
2.
Nature ; 579(7800): 523-527, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32214254

RESUMEN

Spin-triplet superconductors are condensates of electron pairs with spin 1 and an odd-parity wavefunction1. An interesting manifestation of triplet pairing is the chiral p-wave state, which is topologically non-trivial and provides a natural platform for realizing Majorana edge modes2,3. However, triplet pairing is rare in solid-state systems and has not been unambiguously identified in any bulk compound so far. Given that pairing is usually mediated by ferromagnetic spin fluctuations, uranium-based heavy-fermion systems containing f-electron elements, which can harbour both strong correlations and magnetism, are considered ideal candidates for realizing spin-triplet superconductivity4. Here we present scanning tunnelling microscopy studies of the recently discovered heavy-fermion superconductor UTe2, which has a superconducting transition temperature of 1.6 kelvin5. We find signatures of coexisting Kondo effect and superconductivity that show competing spatial modulations within one unit cell. Scanning tunnelling spectroscopy at step edges reveals signatures of chiral in-gap states, which have been predicted to exist at the boundaries of topological superconductors. Combined with existing data that indicate triplet pairing in UTe2, the presence of chiral states suggests that UTe2 is a strong candidate for chiral-triplet topological superconductivity.

3.
Ann Surg ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38921829

RESUMEN

OBJECTIVES: This trial examines the impact of the Provider Awareness and Cultural dexterity Toolkit for Surgeons (PACTS) curriculum on surgical residents' knowledge, cross-cultural care, skills, and beliefs. SUMMARY BACKGROUND DATA: Cross-cultural training of providers may reduce healthcare outcome disparities, but its effectiveness in surgical trainees is unknown. METHODS: PACTS focuses on developing skills needed for building trust, working with patients with limited English proficiency, optimizing informed consent, and managing pain. The PACTS trial was a randomized crossover trial of 8 academic general surgery programs in the United States: The Early group ("Early") received PACTS between Periods 1 and 2, while the Delayed group ("Delayed") received PACTS between Periods 2 and 3. Residents were assessed pre- and post-intervention on Knowledge, Cross-Cultural Care, Self-Assessed Skills, and Beliefs. Chi-square and Fisher's exact tests were conducted to evaluate within- and between-intervention group differences. RESULTS: Of 406 residents enrolled, 315 were exposed to the complete PACTS curriculum. Early residents' Cross-Cultural Care (79.6% to 88.2%, P<0.0001), Self-Assessed Skills (74.5% to 85.0%, P<0.0001), and Beliefs (89.6% to 92.4%, P=0.0028) improved after PACTS; Knowledge scores (71.3% to 74.3%, P=0.0661) were unchanged. Delayed resident scores pre- to post-PACTS showed minimal improvements in all domains. When comparing the two groups at Period 2, Early residents had modest improvement in all 4 assessment areas, with statistically significant increase in Beliefs (92.4% vs 89.9%, P=0.0199). CONCLUSION: The PACTS curriculum is a comprehensive tool that improved surgical residents' knowledge, preparedness, skills, and beliefs, which will help with caring for diverse patient populations.

4.
Ann Surg Oncol ; 31(5): 3249-3260, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38294612

RESUMEN

BACKGROUND: Despite existing society guidelines, management of pancreatic (PanNEN) and small bowel (SBNEN) neuroendocrine neoplasms remains inconsistent. The purpose of this study was to identify patient- and/or disease-specific characteristics associated with increased odds of being offered surgery for PanNEN and SBNEN. PATIENTS AND METHODS: The Surveillance, Epidemiology, and End Results (SEER) Program database and the National Cancer Database (NCDB) were queried for patients with PanNEN/SBNEN. Demographic and pathologic data were compared between patients who were offered surgery and those who were not. Multivariate logistic regression was performed to identify factors independently associated with being offered surgery. RESULTS: In SEER, there were 3641 patients with PanNEN (54.7% were offered surgery) and 5720 with SBNEN (86.0% were offered surgery). On multivariate analysis of SEER, non-white race was associated with decreased odds of surgery offer for SBNEN [odds ratio (OR) 0.58, p < 0.001], but not PanNEN (p = 0.187). In NCDB, there were 28,483 patients with PanNEN (57.5% were offered surgery) and 42,675 with SBNEN (86.9% were offered surgery). On multivariate analysis of NCDB, non-white race was also associated with decreased odds of surgery offer for SBNEN (OR 0.61, p < 0.001) but not PanNEN (p = 0.414). CONCLUSIONS: This study's findings suggest that, in addition to previously reported disparities in surgical resection and surgery refusal rates, racial/ethnic disparities also exist earlier in the course of treatment, with non-white patients being less likely to be offered surgery for SBNEN but not for PanNEN; this is potentially due to discrepancies in rates of referral to academic centers for pancreas and small bowel malignancies.


Asunto(s)
Neoplasias Duodenales , Tumores Neuroendocrinos , Neoplasias Pancreáticas , Humanos , Tumores Neuroendocrinos/cirugía , Páncreas/patología , Neoplasias Pancreáticas/patología , Programa de VERF , Población Blanca , Estados Unidos , Blanco
5.
Respir Res ; 25(1): 248, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38890699

RESUMEN

BACKGROUND: The term "post-COVID-19 condition" refers to the symptomatology that appears between four to twelve weeks after Covid-19 infection. These symptoms can persist for weeks or even months, significantly diminishing the quality of life for affected individuals. The primary objective of this study was to assess the effectiveness of pulmonary rehabilitation programs and/or respiratory muscle training on respiratory sequelae in patients with post-COVID condition. METHODS: The literature search was conducted in the following databases: PubMed, PEDro, Embase, Cochrane, Scopus, and Web of Science. Randomized clinical trials were included in which participants were aged 18 years or older. Articles were excluded if at least one of the therapies did not involve pulmonary rehabilitation or respiratory muscle training, if the participants were COVID positive, if studies lacked results, and finally, if interventions were conducted without supervision or at home. This review only encompasses supervised non-virtual interventions. This study adheres to the PRISMA statement and has been registered in the PROSPERO database (CRD42023433843). RESULTS: The outcomes obtained in the included studies are assessed across the following variables: Exercise capacity using the 6-minute walk test, Dyspnea, fatigue, Pulmonary function, Maximum inspiratory pressure, and Quality of life. CONCLUSION: Despite the absence of a specific treatment at present, it was evident from this review that a well-structured pulmonary rehabilitation program that incorporates both aerobic and muscular strength exercises along with techniques and inspiratory muscle exercises was the most effective form of treatment.


Asunto(s)
Ejercicios Respiratorios , COVID-19 , Humanos , COVID-19/rehabilitación , Ejercicios Respiratorios/métodos , Resultado del Tratamiento , Músculos Respiratorios/fisiopatología , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Tolerancia al Ejercicio/fisiología , Síndrome Post Agudo de COVID-19
6.
Gastrointest Endosc ; 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38518978

RESUMEN

BACKGROUND: /aims: Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) has emerged as an alternative for the local treatment of unresectable pancreatic ductal adenocarcinoma (PDAC). We aim to assess the feasibility and safety of EUS-RFA in patients with unresectable PDAC. METHODS: The following was a historic cohort compounded by locally advanced (LA) and metastatic (m) PDAC naïve patients, who underwent EUS-RFA between October 2019 to March 2022. EUS-RFA was performed with a 19-g needle electrode with a 10 mm active tip for energy delivery. Study primary endpoints were feasibility, safety, and clinical follow-up; secondary endpoints were performance status (PS), local control (LC) and overall survival (OS). RESULTS: Twenty-six patients were selected: 15/26 LA-PDAC and 11/26 mPDAC. Technical success was achieved in all patients with no major adverse events. Six months after EUS-RFA, OS was 11/26 (42.3%), with significant PS improvement (P=.03). LC was achieved, with tumor reduction from 39.5 to 26 mm (P=.04). Post-treatment hypodense necrotic area was observed at six-month follow-up in 11/11 alive cases. Metastatic disease was a significant factor for OS worsening (HR 5.021; IC 95% 1.589 - 15.87; P=.004) CONCLUSIONS: EUS-RFA of pancreatic adenocarcinoma is a minimally invasive and safe technique that may have an important role as targeted therapy for local treatment of unresectable cases, as well as an alternative for poor surgical candidates. Also, RFA may play a role in downstaging cancer with potential OS increase in non-metastatic cases. Large prospective cohorts are required to evaluate this technique in clinical practice.

7.
PLoS Comput Biol ; 19(7): e1011264, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37410779

RESUMEN

This work presents a methodology to evaluate the bioenergetic feasibility of alternative metabolic pathways for a given microbial conversion, optimising their energy yield and driving forces as a function of the concentration of metabolic intermediates. The tool, based on thermodynamic principles and multi-objective optimisation, accounts for pathway variants in terms of different electron carriers, as well as energy conservation (proton translocating) reactions within the pathway. The method also accommodates other constraints, some of them non-linear, such as the balance of conserved moieties. The approach involves the transformation of the maximum energy yield problem into a multi-objective mixed-integer linear optimisation problem which is then subsequently solved using the epsilon-constraint method, highlighting the trade-off between yield and rate in metabolic reactions. The methodology is applied to analyse several pathway alternatives occurring during propionate oxidation in anaerobic fermentation processes, as well as to the reverse TCA cycle pathway occurring during autotrophic microbial CO2 fixation. The results obtained using the developed methodology match previously reported literature and bring about insights into the studied pathways.


Asunto(s)
Ciclo del Ácido Cítrico , Redes y Vías Metabólicas , Metabolismo Energético , Fermentación , Termodinámica
8.
Appl Microbiol Biotechnol ; 108(1): 106, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38217255

RESUMEN

Glioblastoma is one of the most lethal tumors, displaying striking cellular heterogeneity and drug resistance. The prognosis of patients suffering from glioblastoma after 5 years is only 5%. In the present work, capsaicin analogues bearing modifications on the acyl chain with long-chain fatty acids showed promising anti-tumoral activity by its cytotoxicity on U-87 and U-138 glioblastoma multiforme cells. The capsaicin analogues were enzymatically synthetized with cross-linked enzyme aggregates of lipase B from Candida antarctica (CALB). The catalytic performance of recombinant CALB-CLEAs was compared to their immobilized form on a hydrophobic support. After 72 h of reaction, the synthesis of capsaicin analogues from linoleic acid, docosahexaenoic acid, and punicic acid achieved a maximum conversion of 69.7, 8.3 and 30.3% with CALB-CLEAs, respectively. Similar values were obtained with commercial CALB, with conversion yields of 58.3, 24.2 and 22% for capsaicin analogues from linoleic acid, DHA and punicic acid, respectively. Olvanil and dohevanil had a significant cytotoxic effect on both U-87 and U-138 glioblastoma cells. Irrespective of the immobilization form, CALB is an efficient biocatalyst for the synthesis of anti-tumoral capsaicin derivatives. KEY POINTS: • This is the first report concerning the enzymatic synthesis of capsaicin analogues from docosahexaenoic acid and punicic acid with CALB-CLEAs. • The viability U-87 and U-138 glioblastoma cells was significantly affected after incubation with olvanil and dohevanil. • Capsaicin analogues from fatty acids obtained by CALB-CLEAs are promising candidates for therapeutic use as cytotoxic agents in glioblastoma cancer cells.


Asunto(s)
Capsaicina , Glioblastoma , Humanos , Capsaicina/farmacología , Enzimas Inmovilizadas/metabolismo , Glioblastoma/tratamiento farmacológico , Proteínas Fúngicas/metabolismo
9.
Surg Technol Int ; 442024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38527331

RESUMEN

BACKGROUND: Pancreatoduodenectomy is a highly complex surgical procedure associated with high postoperative morbidity and mortality. Treatment of postoperative pain is crucial to preventing chronic pain and further complications. Opioids are the leading treatment modality for acute postoperative pain for all surgical procedures in the US, contributing to the opioid epidemic, a crisis causing death and lifelong impairment in many patients. Multimodal analgesia techniques, such as the transversus abdominis plane (TAP) block, are suggested to reduce perioperative opioid usage. This exploratory literature review aims to investigate the use of TAP block in postoperative pain and opioid use in patients undergoing pancreatoduodenectomy. MATERIALS AND METHODS: A search strategy developed from Cochrane best practice recommendations was applied to a comprehensive search of PubMed, Scopus, and PsycINFO databases, yielding three articles of relevance in patients having pancreatic surgery. RESULTS: Previous research demonstrates TAP block efficacy in decreasing opiate consumption after major abdominal surgery; however, there is a paucity of data regarding opioid consumption in pancreatoduodenectomy patients. CONCLUSION: Research in relation to TAP block analgesia is varied given the variety of approaches, techniques, and timing of the TAP block procedure. Future research should seek to elucidate the role of TAP blocks in reducing postoperative pain and opioid consumption in pancreatoduodenectomy patients.

10.
Int J Mol Sci ; 25(11)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38892240

RESUMEN

A detailed study of palmitate metabolism in pancreatic islets subject to different experimental conditions, like varying concentrations of glucose, as well as fed or starved conditions, has allowed us to explore the interaction between the two main plasma nutrients and its consequences on hormone secretion. Palmitate potentiates glucose-induced insulin secretion in a concentration-dependent manner, in a physiological range of both palmitate (0-2 mM) and glucose (6-20 mM) concentrations; at glucose concentrations lower than 6 mM, no metabolic interaction with palmitate was apparent. Starvation (48 h) increased islet palmitate oxidation two-fold, and the effect was resistant to its inhibition by glucose (6-20 mM). Consequently, labelled palmitate and glucose incorporation into complex lipids were strongly suppressed, as well as glucose-induced insulin secretion and its potentiation by palmitate. 2-bromostearate, a palmitate oxidation inhibitor, fully recovered the synthesis of complex lipids and insulin secretion. We concluded that palmitate potentiation of the insulin response to glucose is not attributable to its catabolic mitochondrial oxidation but to its anabolism to complex lipids: islet lipid biosynthesis is dependent on the uptake of plasma fatty acids and the supply of α-glycerol phosphate from glycolysis. Islet secretion of glucagon and somatostatin showed a similar dependence on palmitate anabolism as insulin. The possible mechanisms implicated in the metabolic coupling between glucose and palmitate were commented on. Moreover, possible mechanisms responsible for islet gluco- or lipotoxicity after a long-term stimulation of insulin secretion were also discussed. Our own data on the simultaneous stimulation of insulin, glucagon, and somatostatin by glucose, as well as their modification by 2-bromostearate in perifused rat islets, give support to the conclusion that increased FFA anabolism, rather than its mitochondrial oxidation, results in a potentiation of their stimulated release. Starvation, besides suppressing glucose stimulation of insulin secretion, also blocks the inhibitory effect of glucose on glucagon secretion: this suggests that glucagon inhibition might be an indirect or direct effect of insulin, but not of glucose. In summary, there seems to exist three mechanisms of glucagon secretion stimulation: 1. glucagon stimulation through the same secretion coupling mechanism as insulin, but in a different range of glucose concentrations (0 to 5 mM). 2. Direct or indirect inhibition by secreted insulin in response to glucose (5-20 mM). 3. Stimulation by increased FFA anabolism in glucose intolerance or diabetes in the context of hyperlipidemia, hyperglycemia, and hypo-insulinemia. These conclusions were discussed and compared with previous published data in the literature. Specially, we discussed the mechanism for inhibition of glucagon release by glucose, which was apparently contradictory with the secretion coupling mechanism of its stimulation.


Asunto(s)
Glucagón , Glucosa , Secreción de Insulina , Insulina , Islotes Pancreáticos , Glucosa/metabolismo , Animales , Insulina/metabolismo , Glucagón/metabolismo , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/efectos de los fármacos , Secreción de Insulina/efectos de los fármacos , Ácidos Grasos/metabolismo , Ratas , Palmitatos/metabolismo , Palmitatos/farmacología , Oxidación-Reducción/efectos de los fármacos
11.
Int J Mol Sci ; 25(8)2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38674067

RESUMEN

Photobiomodulation (PBM) is a procedure that uses light to modulate cellular functions and biological processes. Over the past decades, PBM has gained considerable attention for its potential in various medical applications due to its non-invasive nature and minimal side effects. We conducted a narrative review including articles about photobiomodulation, LED light therapy or low-level laser therapy and their applications on dermatology published over the last 6 years, encompassing research studies, clinical trials, and technological developments. This review highlights the mechanisms of action underlying PBM, including the interaction with cellular chromophores and the activation of intracellular signaling pathways. The evidence from clinical trials and experimental studies to evaluate the efficacy of PBM in clinical practice is summarized with a special emphasis on dermatology. Furthermore, advancements in PBM technology, such as novel light sources and treatment protocols, are discussed in the context of optimizing therapeutic outcomes and improving patient care. This narrative review underscores the promising role of PBM as a non-invasive therapeutic approach with broad clinical applicability. Despite the need for further research to develop standard protocols, PBM holds great potential for addressing a wide range of medical conditions and enhancing patient outcomes in modern healthcare practice.


Asunto(s)
Terapia por Luz de Baja Intensidad , Piel , Humanos , Terapia por Luz de Baja Intensidad/métodos , Piel/efectos de la radiación , Piel/metabolismo , Animales , Enfermedades de la Piel/radioterapia , Enfermedades de la Piel/terapia , Luz , Fototerapia/métodos
12.
J Hand Ther ; 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38453573

RESUMEN

BACKGROUND: Lateral Epicondylalgia (LE) represents one of the most common injuries of the upper limb. It is necessary to find effective treatments that reduce pain and increase functionality. PURPOSE: To determine the effects of an integrated intervention of Pulsed Negative Pressure Myofascial Vacuum Therapy (VT), Percutaneous Electrolysis (PE) and eccentric exercise (EE) in the treatment of LE compared versus Manual Therapy soft tissue mobilization (MT) and Ultrasound therapy (US) and EE. STUDY DESIGN: Single-blind randomized controlled trial. METHODS: Forty participants, with unilateral LE, were randomly divided into two groups: VT + PE + EE group (n = 20) and MT + US + EE group (n = 20). The VT + PE + EE group received one weekly session for four weeks and a regimen of EE daily at-home, and the MT + US + EE group received 10 sessions over a period of two weeks and a regimen of EE daily at-home. Numerical pain rating scale (NPRS), range of motion (ROM) pressure pain threshold (PPT) and function (PRTEE questionnaire) were measured before treatment, at the end of treatment, and at one- and three-month follow-ups. RESULTS: The statistically significant improvements were found post-treatment, favoring the VT + PE group in pain intensity (p < 0.001; ES = 0.408), PRTEE-S Pain (p = 0.001; ES = 0.377), PRTEE-S Specific function (p = 0.004; ES = 0.306) and PRTEE-S Total (p = 0.001; ES = 0.355). The VT + PE + EE treatment showed greater effectiveness than the MT + US + EE treatment at immediate post-treatment, as well as at the one-month and three-months follow-up. CONCLUSIONS: VT and PE added to an EE program could be an effective treatment for pain, ROM, PPT, and function in patients with LE.

13.
Int Wound J ; 21(4): e14565, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38146127

RESUMEN

Chronic wounds contribute to significant healthcare and economic burden worldwide. Wound assessment remains challenging given its complex and dynamic nature. The use of artificial intelligence (AI) and machine learning methods in wound analysis is promising. Explainable modelling can help its integration and acceptance in healthcare systems. We aim to develop an explainable AI model for analysing vascular wound images among an Asian population. Two thousand nine hundred and fifty-seven wound images from a vascular wound image registry from a tertiary institution in Singapore were utilized. The dataset was split into training, validation and test sets. Wound images were classified into four types (neuroischaemic ulcer [NIU], surgical site infections [SSI], venous leg ulcers [VLU], pressure ulcer [PU]), measured with automatic estimation of width, length and depth and segmented into 18 wound and peri-wound features. Data pre-processing was performed using oversampling and augmentation techniques. Convolutional and deep learning models were utilized for model development. The model was evaluated with accuracy, F1 score and receiver operating characteristic (ROC) curves. Explainability methods were used to interpret AI decision reasoning. A web browser application was developed to demonstrate results of the wound AI model with explainability. After development, the model was tested on additional 15 476 unlabelled images to evaluate effectiveness. After the development on the training and validation dataset, the model performance on unseen labelled images in the test set achieved an AUROC of 0.99 for wound classification with mean accuracy of 95.9%. For wound measurements, the model achieved AUROC of 0.97 with mean accuracy of 85.0% for depth classification, and AUROC of 0.92 with mean accuracy of 87.1% for width and length determination. For wound segmentation, an AUROC of 0.95 and mean accuracy of 87.8% was achieved. Testing on unlabelled images, the model confidence score for wound classification was 82.8% with an explainability score of 60.6%. Confidence score was 87.6% for depth classification with 68.0% explainability score, while width and length measurement obtained 93.0% accuracy score with 76.6% explainability. Confidence score for wound segmentation was 83.9%, while explainability was 72.1%. Using explainable AI models, we have developed an algorithm and application for analysis of vascular wound images from an Asian population with accuracy and explainability. With further development, it can be utilized as a clinical decision support system and integrated into existing healthcare electronic systems.


Asunto(s)
Algoritmos , Inteligencia Artificial , Humanos , Programas Informáticos , Aprendizaje Automático , Instituciones de Salud
14.
Angew Chem Int Ed Engl ; : e202410283, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38943496

RESUMEN

The direct synthesis of alkenes from alkynes usually requires the use of transition-metal catalysts. Unfortunately, efficient biocatalytic alternatives for this transformation have yet to be discovered. Herein, the selective bioreduction of electron-deficient alkynes to alkenes catalysed by ene-reductases (EREDs) is described. Alkynes bearing ketone, aldehyde, ester, and nitrile moieties have been effectively reduced with excellent conversions and stereoselectivities, observing clear trends for the E/Z ratios depending on the nature of the electron-withdrawing group. In the case of cyanoalkynes, (Z)-alkenes were obtained as the major product, and the reaction scope was expanded to a wide variety of aromatic substrates (up to >99% conversion, and Z/E stereoselectivities of up to >99/1). Other alkynes containing aldehyde, ketone, or ester functionalities also proved to be excellent substrates, and interestingly gave the corresponding (E)-alkenes. Preparative biotransformations were performed on a 0.4 mmol scale, producing the desired (Z)-cyanoalkenes with good to excellent isolated yields (63-97%). This novel reactivity has been rationalised through molecular docking by predicting the binding poses of key molecules in the ERED-pu-0006 active site.

15.
J Neurovirol ; 29(1): 116-119, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36348234

RESUMEN

Progressive multifocal leukoencephalopathy (PML) is a demyelinating central nervous system disease infection by JC virus (JCV) in patients with a significant decline in cellular immunity. No specific treatment has demonstrated efficacy, and the disease progresses to death in most patients. Recent findings have shown stabilization or improvement of PML lesions after treatment with checkpoint inhibitors (CPI) based on immune reconstitution. Nevertheless, immunotherapy may specifically cause autoimmune diseases or may deteriorate pre-existing ones. We report a case of a patient under treatment for advanced ductal breast carcinoma and systemic sclerosis, who developed PML. The therapeutic approach included withdrawal of drugs with possible immunosuppressive effect and treatment with pembrolizumab. In the absence of reliable markers to predict CPIs response and a concern for an autoimmune worsening, immunotherapy was administered late in the course of the disease. Finally, she did not experience an autoimmune disease flare-up; however, pembrolizumab could not prevent disease progression. We believe that potential autoimmune complications should not delay treatment initiation with CPIs in PML.


Asunto(s)
Neoplasias de la Mama , Virus JC , Leucoencefalopatía Multifocal Progresiva , Esclerodermia Sistémica , Femenino , Humanos , Progresión de la Enfermedad , Esclerodermia Sistémica/complicaciones , Neoplasias de la Mama/complicaciones
16.
Mol Phylogenet Evol ; 183: 107774, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36972795

RESUMEN

Speciation with gene flow often leads to ambiguous phylogenetic reconstructions, reticulate patterns of relatedness and conflicting nuclear versus mitochondrial (mt) lineages. Here we employed a fragment of the COI mtDNA gene and nuclear genome-wide data (3RAD) to assess the diversification history of Sphenarium, an orthopteran genus of great economic importance in Mexico that is presumed to have experienced hybridisation events in some of its species. We carried out separate phylogenetic analyses to evaluate the existence of mito-nuclear discordance in the species relationships, and also assessed the genomic diversity and population genomic structure and investigated the existence of interspecific introgression and species limits of the taxa involved based on the nuclear dataset. The species delineation analyses discriminated all the currently recognised species, but also supported the existence of four undescribed species. The mt and nuclear topologies had four discordant species relationships that can be explained by mt introgression, where the mt haplotypes of S. purpurascens appear to have replaced those of S. purpurascens A and B, S. variabile and S. zapotecum. Moreover, our analyses supported the existence of nuclear introgression events between four species pairs that are distributed in the Sierra Madre del Sur province in southeast Mexico, with three of them occurring in the Tehuantepec Isthmus region. Our study highlights the relevance of genomic data to address the relative importance of allopatric isolation versus gene flow in speciation.


Asunto(s)
Saltamontes , Animales , Filogenia , Saltamontes/genética , México , ADN Mitocondrial/genética , ADN Mitocondrial/química , Mitocondrias/genética
17.
J Gen Intern Med ; 38(11): 2613-2620, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37095331

RESUMEN

Telehealth services, specifically telemedicine audio-video and audio-only patient encounters, expanded dramatically during the COVID-19 pandemic through temporary waivers and flexibilities tied to the public health emergency. Early studies demonstrate significant potential to advance the quintuple aim (patient experience, health outcomes, cost, clinician well-being, and equity). Supported well, telemedicine can particularly improve patient satisfaction, health outcomes, and equity. Implemented poorly, telemedicine can facilitate unsafe care, worsen disparities, and waste resources. Without further action from lawmakers and agencies, payment will end for many telemedicine services currently used by millions of Americans at the end of 2024. Policymakers, health systems, clinicians, and educators must decide how to support, implement, and sustain telemedicine, and long-term studies and clinical practice guidelines are emerging to provide direction. In this position statement, we use clinical vignettes to review relevant literature and highlight where key actions are needed. These include areas where telemedicine must be expanded (e.g., to support chronic disease management) and where guidelines are needed (e.g., to prevent inequitable offering of telemedicine services and prevent unsafe or low-value care). We provide policy, clinical practice, and education recommendations for telemedicine on behalf of the Society of General Internal Medicine. Policy recommendations include ending geographic and site restrictions, expanding the definition of telemedicine to include audio-only services, establishing appropriate telemedicine service codes, and expanding broadband access to all Americans. Clinical practice recommendations include ensuring appropriate telemedicine use (for limited acute care situations or in conjunction with in-person services to extend longitudinal care relationships), that the choice of modality be done through patient-clinician shared decision-making, and that health systems design telemedicine services through community partnerships to ensure equitable implementation. Education recommendations include developing telemedicine-specific educational strategies for trainees that align with accreditation body competencies and providing educators with protected time and faculty development resources.


Asunto(s)
COVID-19 , Telemedicina , Humanos , Estados Unidos , Pandemias , Medicina Interna , Políticas
18.
Ann Hematol ; 102(12): 3613-3620, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37782372

RESUMEN

Although several scores stratify venous thromboembolism (VTE) risk in solid tumors, hematologic malignancies (HM) are underrepresented. To develop an internal and external validation of a logistic regression model to predict VTE risk in hospitalized HM patients. Validation of the existing VTE predictive model was performed through a prospective case-control study in 496 hospitalized HM patients between December 2010 and 2020 at the Arnaldo Milián University Hospital, Cuba. The predictive model designed with data from 285 patients includes 5 predictive factors: hypercholesterolemia, tumoral activity, use of thrombogenic drugs, diabetes mellitus, and immobilization. The model was internally validated using bootstrap analysis. External validation was realized in a prospective cohort of 211 HM patients. The predictive model had a 76.4% negative predictive value (NPV) and an 81.7% positive predictive value (PPV) in the bootstrapping validation. The area under curve (AUC) in the bootstrapping set was 0.838. Accuracy was 80.1% and 82.9% in the internal and external validation, respectively. In the external validation, the model produced 89.7% of NPV, 67.7% of PPV, 74.6% of sensitivity, and 86.2% of specificity. The AUC in the external validation was 0.900. VTE predictive model is a reproducible and simple tool with good accuracy and discrimination.


Asunto(s)
Neoplasias Hematológicas , Neoplasias , Tromboembolia Venosa , Humanos , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etiología , Estudios de Casos y Controles , Factores de Riesgo , Medición de Riesgo , Neoplasias Hematológicas/complicaciones , Estudios Retrospectivos
19.
Endoscopy ; 55(8): 719-727, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36781156

RESUMEN

BACKGROUND: We aimed to develop a convolutional neural network (CNN) model for detecting neoplastic lesions during real-time digital single-operator cholangioscopy (DSOC) and to clinically validate the model through comparisons with DSOC expert and nonexpert endoscopists. METHODS: In this two-stage study, we first developed and validated CNN1. Then, we performed a multicenter diagnostic trial to compare four DSOC experts and nonexperts against an improved model (CNN2). Lesions were classified into neoplastic and non-neoplastic in accordance with Carlos Robles-Medranda (CRM) and Mendoza disaggregated criteria. The final diagnosis of neoplasia was based on histopathology and 12-month follow-up outcomes. RESULTS: In stage I, CNN2 achieved a mean average precision of 0.88, an intersection over the union value of 83.24 %, and a total loss of 0.0975. For clinical validation, a total of 170 videos from newly included patients were analyzed with the CNN2. Half of cases (50 %) had neoplastic lesions. This model achieved significant accuracy values for neoplastic diagnosis, with a 90.5 % sensitivity, 68.2 % specificity, and 74.0 % and 87.8 % positive and negative predictive values, respectively. The CNN2 model outperformed nonexpert #2 (area under the receiver operating characteristic curve [AUC]-CRM 0.657 vs. AUC-CNN2 0.794, P < 0.05; AUC-Mendoza 0.582 vs. AUC-CNN2 0.794, P < 0.05), nonexpert #4 (AUC-CRM 0.683 vs. AUC-CNN2 0.791, P < 0.05), and expert #4 (AUC-CRM 0.755 vs. AUC-CNN2 0.848, P < 0.05; AUC-Mendoza 0.753 vs. AUC-CNN2 0.848, P < 0.05). CONCLUSIONS: The proposed CNN model distinguished neoplastic bile duct lesions with good accuracy and outperformed two nonexpert and one expert endoscopist.


Asunto(s)
Inteligencia Artificial , Neoplasias , Humanos , Redes Neurales de la Computación , Curva ROC , Valor Predictivo de las Pruebas
20.
J Surg Res ; 287: 149-159, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36933546

RESUMEN

INTRODUCTION: Due to the COVID-19 pandemic, the recruitment cycle for the 2021 Match was performed virtually. This Association for Surgical Education (ASE)-sponsored survey set out to study applicants' ability to assess the factors contributing to fit through video interviews. METHODS: An IRB-approved, online, anonymous survey was distributed to surgical applicants at a single academic institution and through the ASE clerkship director distribution list between the rank order list certification deadline and Match Day. Applicants used 5-point Likert-type scales to rate factors for importance to fit and their ease of assessment through video interviewing. A variety of recruitment activities were also rated by applicants for their perceived helpfulness in assessment of fit. RESULTS: One hundred and eighty-three applicants responded to the survey. The three most important factors for applicant fit were how much the program cared, how satisfied residents seem with their program, and how well residents get along. Resident rapport, diversity of the patient population, and quality of the facilities were hardest to assess through video interviews. In general, diversity-related factors were more important to female and non-White applicants, but not more difficult to assess. Interview day and resident-only virtual panels were the most helpful recruitment activities, while virtual campus tours, faculty-only panels, and a program's social media were the least helpful. CONCLUSIONS: This study provides valuable insight into the limitations of virtual recruitment for surgical applicants' perception of fit. These findings and the recommendations herein should be taken into consideration by residency program leadership to ensure successful recruitment of diverse residency classes.


Asunto(s)
COVID-19 , Internado y Residencia , Humanos , Femenino , Pandemias , Relaciones Interpersonales , Selección de Personal , Encuestas y Cuestionarios
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