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Medicinas Complementárias
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1.
Obstet Gynecol ; 143(2): 204-209, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37989143

RESUMEN

There is an urgent need to diversify the physician workforce in obstetrics and gynecology to serve a diverse patient population and mitigate disparities in care. There is a paucity of data on how to improve recruitment of individuals from underrepresented minoritized groups to the field of obstetrics and gynecology. This article outlines important steps for sharing the department's commitment to diversity, equity, and inclusion; addresses ways to attract a diverse applicant pool; and reviews the importance of and need to perform a holistic review of applicants. This commentary also shares some approaches to support faculty and trainees that may lead to sustained increases in diversity. Using this framework, the authors successfully increased the diversity of their obstetrics and gynecology residency program.


Asunto(s)
Ginecología , Internado y Residencia , Obstetricia , Médicos , Femenino , Embarazo , Humanos , Ginecología/educación , Obstetricia/educación
2.
bioRxiv ; 2024 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-38106022

RESUMEN

Cancer immunotherapies have produced remarkable results in B-cell malignancies; however, optimal cell surface targets for many solid cancers remain elusive. Here, we present an integrative proteomic, transcriptomic, and epigenomic analysis of tumor specimens along with normal tissues to identify biologically relevant cell surface proteins that can serve as immunotherapeutic targets for neuroblastoma, an often-fatal childhood cancer of the developing nervous system. We apply this approach to human-derived cell lines (N=9) and cell/patient-derived xenograft (N=12) models of neuroblastoma. Plasma membrane-enriched mass spectrometry identified 1,461 cell surface proteins in cell lines and 1,401 in xenograft models, respectively. Additional proteogenomic analyses revealed 60 high-confidence candidate immunotherapeutic targets and we prioritized Delta-like canonical notch ligand 1 (DLK1) for further study. High expression of DLK1 directly correlated with the presence of a super-enhancer spanning the DLK1 locus. Robust cell surface expression of DLK1 was validated by immunofluorescence, flow cytometry, and immunohistochemistry. Short hairpin RNA mediated silencing of DLK1 in neuroblastoma cells resulted in increased cellular differentiation. ADCT-701, a DLK1-targeting antibody-drug conjugate (ADC), showed potent and specific cytotoxicity in DLK1-expressing neuroblastoma xenograft models. Moreover, DLK1 is highly expressed in several adult cancer types, including adrenocortical carcinoma (ACC), pheochromocytoma/paraganglioma (PCPG), hepatoblastoma, and small cell lung cancer (SCLC), suggesting potential clinical benefit beyond neuroblastoma. Taken together, our study demonstrates the utility of comprehensive cancer surfaceome characterization and credentials DLK1 as an immunotherapeutic target. Highlights: Plasma membrane enriched proteomics defines surfaceome of neuroblastomaMulti-omic data integration prioritizes DLK1 as a candidate immunotherapeutic target in neuroblastoma and other cancersDLK1 expression is driven by a super-enhancer DLK1 silencing in neuroblastoma cells results in cellular differentiation ADCT-701, a DLK1-targeting antibody-drug conjugate, shows potent and specific cytotoxicity in DLK1-expressing neuroblastoma preclinical models.

3.
J Nat Prod ; 86(12): 2661-2671, 2023 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-37972998

RESUMEN

Chemical investigation of the antimalarial medicinal plant Clerodendrum polycephalum led to the isolation of five new diterpenoids, including ajugarins VII-X (1-4) and teuvincenone K (5), along with four known compounds, namely, 12,16-epoxy-6,11,14,17-tetrahydroxy-17(15 → 16)-abeo-5,8,11,13,15-abietapentaen-7-one (6), methyl pheophorbide A (7), loliolide (8), and acacetin (9). The chemical structures of the new compounds were elucidated using NMR spectroscopy, mass spectrometry, circular dichroism, as well as density functional theory calculations. All compounds were evaluated for in vitro activity against Plasmodium falciparum 3D7 malaria parasites with methyl pheophorbide A (7) showing the strongest activity (IC50 4.49 µM). Subsequent in vivo testing in a Plasmodium berghei chemosuppression model showed that compound 7 significantly attenuated peripheral blood parasitemia, leading to 79% and 87% chemosuppression following oral doses at 10 and 20 mg/kg, respectively.


Asunto(s)
Antimaláricos , Clerodendrum , Malaria , Parásitos , Animales , Malaria/tratamiento farmacológico , Malaria/parasitología , Plasmodium falciparum , Extractos Vegetales/química , Antimaláricos/farmacología , Antimaláricos/química , Plasmodium berghei
4.
J Drugs Dermatol ; 22(11): 1111-1117, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37943272

RESUMEN

BACKGROUND: Polymicrobial colonization and resultant biofilm formation significantly impair the process of wound healing. Stagnant tissue repair processes predispose patients to serious complications including systemic infection and limb amputation. Continuous Low-Irradiance Phototherapy (CLIP) is a novel therapeutic approach that delivers blue light at low irradiance for extended periods of time. Bench and preclinical work in the literature indicates that 405 nm light avoids thermal injury of healthy tissue, promotes a cytokine milieu favoring re-epithelialization and angiogenesis, and prevents bacterial and biofilm growth.  Objective: This is the first in-human evaluation of a technology that delivers continuous low-irradiance 405 nm light to chronic wounds. The objective of this study was to determine the safety, feasibility, and ergonomics of this device for the treatment of chronic wounds in adult human subjects. This was not a randomized study to determine device efficacy, although data on outcome were collected. METHODS: In this prospective observational pilot study, participants received the intervention 24 hours per day, 7 days per week, for 4 weeks. Cohort I was conducted from December 2018 to March 2019, with Cohorts II and III ongoing. 25 study participants were recruited by referral (Cohort I: 5 participants, Cohort II: 10 participants, Cohort III: 10 participants). Our primary endpoint was to monitor for safety, assess usability by nurses and physicians, and evaluate patient comfort. The secondary endpoint, although not randomized nor directly compared with standard intervention, was the percentage area reduction (PAR) of the wound.  Results: No adverse events or subject discomfort occurred with the CLIP intervention. The staff treating the study participants reported no ergonomic or compliance issues with the use of the device. The device received high scores in categories assessing practicality and ease of use. There was an average PAR of 29% (SD = 0.42).  Conclusion: This study serves as the first in-human evaluation of extended low-irradiance 405 nm light for chronic wound therapy. The device appears safe and easy to use and had no compliance issues in the outpatient setting. Study participants who received CLIP without interruption saw either partial or complete reduction in wound area.  J Drugs Dermatol. 2023;22(11):1111-1117     doi:10.36849/JDD.7206.


Asunto(s)
Luz , Fototerapia , Adulto , Humanos , Proyectos Piloto , Estudios Prospectivos , Fototerapia/efectos adversos , Citocinas
5.
Neurosurgery ; 93(3): 524-538, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37010324

RESUMEN

BACKGROUND: Focused ultrasound (FUS-T) and stereotactic radiosurgery thalamotomy (SRS-T) targeting the ventral intermediate nucleus are effective incisionless surgeries for essential tremor (ET). However, their efficacy for tremor reduction and, importantly, adverse event incidence have not been directly compared. OBJECTIVE: To present a comprehensive systematic review with network meta-analysis examining both efficacy and adverse events (AEs) of FUS-T vs SRS-T for treating medically refractory ET. METHODS: We conducted a systematic review and network meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using the PubMed and Embase databases. We included all primary FUS-T/SRS-T studies with approximately 1-year follow-up, with unilateral Fahn-Tolosa-Marin Tremor Rating Scale or Clinical Rating Scale for Tremor scores prethalamotomy/post-thalamotomy and/or AEs. The primary efficacy outcome was Fahn-Tolosa-Marin Tremor Rating Scale A+B score reduction. AEs were reported as an estimated incidence. RESULTS: Fifteen studies of 464 patients and 3 studies of 62 patients met inclusion criteria for FUS-T/SRS-T efficacy comparison, respectively. Network meta-analysis demonstrated similar tremor reduction between modalities (absolute tremor reduction: FUS-T: -11.6 (95% CI: -13.3, -9.9); SRS-T: -10.3 (95% CI: -14.2, -6.0). FUS-T had a greater 1-year adverse event rate, particularly imbalance and gait disturbances (10.5%) and sensory disturbances (8.3%). Contralateral hemiparesis (2.7%) often accompanied by speech impairment (2.4%) were most common after SRS-T. There was no correlation between efficacy and lesion volume. CONCLUSION: Our systematic review found similar efficacy between FUS-T and SRS-T for ET, with trend toward higher efficacy yet greater adverse event incidence with FUS-T. Smaller lesion volumes could mitigate FUS-T off-target effects for greater safety.


Asunto(s)
Temblor Esencial , Radiocirugia , Procedimientos Quirúrgicos Ultrasónicos , Humanos , Temblor Esencial/cirugía , Imagen por Resonancia Magnética , Radiocirugia/efectos adversos , Tálamo/cirugía , Resultado del Tratamiento , Temblor/cirugía , Metaanálisis en Red
7.
Neuromodulation ; 26(8): 1823-1830, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35690510

RESUMEN

OBJECTIVES: The aims of this study were to 1) determine the success rate of the tined lead test phase in patients with nonobstructive urinary retention (NOUR), 2) determine predictive factors of a successful test phase in patients with NOUR, and 3) determine long-term treatment efficacy and satisfaction in patients with NOUR. MATERIALS AND METHODS: The first part was a multicenter retrospective study at two centers in The Netherlands. Patients with NOUR received a four-week tined lead test phase. Success was defined as a ≥50% reduction of clean intermittent catheterization frequency or postvoid residual. We analyzed possible predictors of success with multivariable logistic regression. Second, all patients received a questionnaire to assess efficacy, perceived health (Patient Global Impression of Improvement), and treatment satisfaction. RESULTS: This study included 215 consecutive patients (82 men and 133 women) who underwent a tined lead test phase for the treatment of NOUR. The success rate in women was significantly higher than in men, respectively 62% (83/133) and 22% (18/82, p < 0.001). In women, age per ten years (odds ratio [OR] 0.74, 95% CI: 0.59-0.93) and a history of psychiatric illness (OR 3.92, 95% CI: 1.51-10.2), including posttraumatic stress disorder (PTSD), significantly predicted first stage sacral neuromodulation (SNM) success. In men, age per ten years (OR 0.43, 95% CI: 0.25-0.72) and previous transurethral resection of the prostate and/or bladder neck incision (OR 7.71, 95% CI: 1.43-41.5) were significant predictors of success. Conversely, inability to void during a urodynamic study (for women, OR 0.79, 95% CI: 0.35-1.78; for men, OR 3.06, 95% CI: 0.83-11.3) was not predictive of success. Of the patients with a successful first stage, 75% (76/101) responded to the questionnaire at a median follow-up of three years. Of these patients, 87% (66/76) continued to use their SNM system, and 92% (70/76) would recommend SNM to other patients. CONCLUSIONS: A history of psychiatric illness, including PTSD, in women with NOUR increased the odds of first stage SNM success 3.92 times. A previous transurethral resection of the prostate and/or bladder neck incision in men increased the odds of success 7.71 times. In addition, a ten-year age increase was associated with an OR of 0.43 in men and 0.74 in women, indicating a 2.3- and 1.3-times decreased odds of success, respectively.


Asunto(s)
Terapia por Estimulación Eléctrica , Resección Transuretral de la Próstata , Vejiga Urinaria Hiperactiva , Retención Urinaria , Masculino , Humanos , Femenino , Niño , Retención Urinaria/etiología , Retención Urinaria/terapia , Estudios Retrospectivos , Resultado del Tratamiento , Terapia por Estimulación Eléctrica/efectos adversos , Vejiga Urinaria Hiperactiva/terapia
8.
Photobiomodul Photomed Laser Surg ; 40(9): 613-621, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36126289

RESUMEN

Objective: The objective of this study is to report on the bactericidal effects of blue light administered at low irradiance for extended periods of time. Background: Multidrug-resistant organisms (MDROs) utilize biofilms that can limit the efficacy of antibiotics, causing infection and impaired wound healing. Unlike high-energy systems, continuous low-irradiance phototherapy (CLIP) avoids thermal injury of healthy tissue and can be delivered for extended periods. Methods: Four MDRO species, two of which contained different antibiotic resistance genes, were exposed to 405 nm irradiation in vitro. The microbes were incrementally exposed to increasing dose-rates (irradiance; mW/cm2) over a 24-h time period. Cell viability and biomass reduction assays were conducted to quantify the antibacterial/antibiofilm effects. Primary human dermal fibroblasts were also exposed to CLIP to assess whether these dose-rates would impair cell viability or proliferation. Results: CLIP exposure utilizing irradiances as low as 2.78 mW/cm2 delivered over 24 h resulted in a >3.0-log (>99.9%) and >2.0-log (>99.0%) microbial load reduction when organisms were grown in planktonic and biofilm-encapsulated conditions, respectively. Crystal violet biofilm assays revealed destruction of extracellular biofilm architecture following CLIP exposure. Human fibroblast viability and proliferation were unaffected by CLIP. Conclusions: This is the first report demonstrating the antimicrobial efficacy of CLIP for MDROs found in infected wounds. CLIP did not compromise cultured human fibroblast growth and survival. This study demonstrated that very low fluence rates (irradiances) delivered over extended periods are potently antimicrobial. There is translational potential for CLIP to be fabricated as a wearable device that would enable continuous ambulatory care of wounds.


Asunto(s)
Antiinfecciosos , Farmacorresistencia Bacteriana Múltiple , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Violeta de Genciana , Humanos , Fototerapia
9.
Appl Environ Microbiol ; 88(17): e0104922, 2022 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-36000884

RESUMEN

Biological nitrogen fixation requires large amounts of energy in the form of ATP and low potential electrons to overcome the high activation barrier for cleavage of the dinitrogen triple bond. The model aerobic nitrogen-fixing bacteria, Azotobacter vinelandii, generates low potential electrons in the form of reduced ferredoxin (Fd) and flavodoxin (Fld) using two distinct mechanisms via the enzyme complexes Rnf and Fix. Both Rnf and Fix are expressed during nitrogen fixation, but deleting either rnf1 or fix genes has little effect on diazotrophic growth. However, deleting both rnf1 and fix eliminates the ability to grow diazotrophically. Rnf and Fix both use NADH as a source of electrons, but overcoming the energetics of NADH's endergonic reduction of Fd/Fld is accomplished through different mechanisms. Rnf harnesses free energy from the chemiosmotic potential, whereas Fix uses electron bifurcation to effectively couple the endergonic reduction of Fd/Fld to the exergonic reduction of quinone. Different reaction stoichiometries and condition-specific differential gene expression indicate specific roles for the two reactions. This work's complementary physiological studies and thermodynamic modeling reveal how Rnf and Fix balance redox homeostasis in various conditions. Specifically, the Fix complex is required for efficient growth under low oxygen concentrations, while Rnf is presumed to maintain reduced Fd/Fld production for nitrogenase under standard conditions. This work provides a framework for understanding how the production of low potential electrons sustains robust nitrogen fixation in various conditions. IMPORTANCE The availability of fixed nitrogen is critical for life in many ecosystems, from extreme environments to agriculture. Due to the energy demands of biological nitrogen fixation, organisms must tailor their metabolism during diazotrophic growth to deliver the energy requirements to nitrogenase in the form of ATP and low potential electrons. Therefore, a complete understanding of diazotrophic energy metabolism and redox homeostasis is required to understand the impact on ecological communities or to promote crop growth in agriculture through engineered diazotrophs.


Asunto(s)
Azotobacter vinelandii , Adenosina Trifosfato/metabolismo , Ecosistema , Ferredoxinas/metabolismo , NAD/metabolismo , Nitrógeno/metabolismo , Fijación del Nitrógeno , Nitrogenasa/genética , Nitrogenasa/metabolismo
10.
J Am Coll Cardiol ; 80(2): 111-122, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35798445

RESUMEN

BACKGROUND: There is growing interest to disentangle worsening heart failure (WHF) from location of care and move away from hospitalization as a surrogate for acuity. OBJECTIVES: The purpose of this study was to describe the incidence of WHF events across the care continuum from ambulatory encounters to hospitalizations. METHODS: We studied calendar year cohorts of adults with diagnosed heart failure (HF) from 2010-2019 within a large, integrated health care delivery system. Electronic health record (EHR) data were accessed for outpatient encounters, emergency department (ED) visits/observation stays, and hospitalizations. WHF was defined as ≥1 symptom, ≥2 objective findings including ≥1 sign, and ≥1 change in HF-related therapy. Symptoms and signs were ascertained using natural language processing. RESULTS: We identified 103,138 eligible individuals with mean age 73.6 ± 13.7 years, 47.5% women, and mean left ventricular ejection fraction of 51.4% ± 13.7%. There were 1,136,750 unique encounters including 743,039 (65.4%) outpatient encounters, 224,670 (19.8%) ED visits/observation stays, and 169,041 (14.9%) hospitalizations. A total of 126,008 WHF episodes were identified, including 34,758 (27.6%) outpatient encounters, 28,301 (22.5%) ED visits/observation stays, and 62,949 (50.0%) hospitalizations. The annual incidence (events per 100 person-years) of WHF increased from 25 to 33 during the study period primarily caused by outpatient encounters (7 to 10) and ED visits/observation stays (4 to 7). The 30-day rate of hospitalizations for WHF ranged from 8.2% for outpatient encounters to 12.4% for hospitalizations. CONCLUSIONS: ED visits/observation stays and outpatient encounters account for approximately one-half of WHF events, are driving the underlying growth in HF morbidity, and portend a poor short-term prognosis.


Asunto(s)
Prestación Integrada de Atención de Salud , Insuficiencia Cardíaca , Adulto , Anciano , Anciano de 80 o más Años , Diuréticos , Servicio de Urgencia en Hospital , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/terapia , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Volumen Sistólico , Función Ventricular Izquierda
11.
Sci Rep ; 12(1): 11979, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35831352

RESUMEN

The ecosystem of the Naroch Lakes (Belarus) includes three water bodies, Lake Batorino, Lake Myastro and Lake Naroch. These lakes have a common catchment area. At the end of the 80 s, the ecosystem of the Naroch Lakes underwent a transformation, during which the nutrient load on the catchment area decreased, and the concentration of phosphorus as a limiting factor in these water bodies decreased significantly. At the same time, the Naroch Lakes were exposed to zebra mussel (Dreissena polymorpha Pallas) invasion. In the mid-90 s, the biological and hydrochemical characteristics of the ecosystem of the Naroch Lakes stabilized. We show here that complex processes associated with the transformation of the lake ecosystem and affecting both trophic interactions in the Naroch Lakes and the influence of environmental factors on them can be represented using a single parameter, the phase-locking index, PLI. In this case, a statistically significant numerical value of PLI characterizes the phase synchronization of two processes, oscillations of the concentration of total phosphorus, TP, and oscillations of the concentration of chlorophyll, Chl. We show that the phase synchronization of these processes occurs only after the stabilization of the ecosystem of the Naroch Lakes. In the period preceding the transformation of the lake ecosystem, there was no synchronization. Numerical evaluation of PLI as a holistic parameter allows us to characterize the transformation of the lake ecosystem as a whole without resorting to study of complex interactions of various factors involved in this transformation.


Asunto(s)
Dreissena , Lagos , Animales , Clorofila/análisis , Ecosistema , Monitoreo del Ambiente , Eutrofización , Lagos/química , Nitrógeno , Fósforo/análisis , Agua
12.
J Bodyw Mov Ther ; 31: 97-101, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35710229

RESUMEN

OBJECTIVES: Medieval yoga texts claim that a special exercise of the muscles of the anterior abdominal wall, called agnisara, improves digestive function. Main objective of the study was to demonstrate change in the blood flow through superior mesenteric artery (if any) after performance of agnisara. METHODS: Ultrasound examination of the linear and volumetric indicators of blood flow in the superior mesenteric artery (SMA) before and after performing the agnisara yoga exercise 100 times was carried out in 12 healthy volunteers of both sexes (8 of them women). RESULTS: A significant increase in the diameter of the SMA, peak systolic and diastolic velocities, and blood flow in the superior mesenteric artery after performing the agnisara exercise 100 times was found, which contrasts with the established data on a decrease in splanchnic blood flow in humans in response to normal physical activity. CONCLUSION: Properly performed agnisara increases blood flow to the splanchnic region, registered by the SMA, which should contribute to adequate blood supply to the gastrointestinal tract for successful performance of digestive function.


Asunto(s)
Arteria Mesentérica Superior , Circulación Esplácnica , Abdomen , Velocidad del Flujo Sanguíneo , Femenino , Hemodinámica , Humanos , Masculino , Arteria Mesentérica Superior/diagnóstico por imagen , Arteria Mesentérica Superior/fisiología , Circulación Esplácnica/fisiología
13.
Stereotact Funct Neurosurg ; 100(4): 224-235, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35350022

RESUMEN

BACKGROUND: Deep brain stimulation (DBS) targeting the ventral intermediate nucleus (Vim) of the thalamus or the posterior subthalamic area (PSA) are effective treatments for essential tremor (ET). However, their relative efficacy is unknown. OBJECTIVE: Here, we present the first systematic review and network meta-analysis, examining the efficacy of Vim versus PSA DBS for treating medically refractory ET. METHODS: We included all primary studies that reported validated Fahn-Tolosa-Marin Tremor Rating Scale (FTM-TRS) scores pre-/postimplantation or on-/off-stimulation postimplantation, for patients receiving either Vim or PSA DBS. The primary outcome was FTM-TRS score reduction; the secondary outcome was percent reduction in score. We categorized all outcomes as short-term (≤12 months) or long-term (>12 months). RESULTS: For pre-/postimplantation comparisons, 19 and 11 studies met inclusion criteria for short- and long-term follow-ups, respectively. For on-/off-stimulation tremor score comparisons, 8 studies met inclusion criteria for short-term follow-up. Network meta-analysis of pre-/postimplantation tremor scores showed greater tremor reduction with PSA implantation short-term (absolute tremor reduction: PSA: -30.94 [95% confidence interval (CI): -34.93, -26.95]; Vim: -26.26 [95% CI: -33.39, -19.12]; relative tremor reduction: PSA: 63.3% [95% CI: 61.8%-64.8%]; Vim: 57.8% [95% CI: 56.5%-59.0%]). However, there was no difference in efficacy between PSA and Vim DBS when comparing tremor on-versus off-stimulation at short-term follow-up or pre- versus postimplantation tremor reduction long-term. CONCLUSION: Our systematic review highlighted both heterogeneity in scoring systems used and lack of transparency in reporting total scores, limiting direct comparison across studies. We found a modestly superior efficacy with PSA stimulation in the short term, but no difference in tremor reduction long-term.


Asunto(s)
Estimulación Encefálica Profunda , Temblor Esencial , Temblor Esencial/terapia , Humanos , Metaanálisis en Red , Tálamo/cirugía , Resultado del Tratamiento , Temblor/terapia , Núcleos Talámicos Ventrales/fisiología
14.
mBio ; 12(6): e0259321, 2021 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-34903060

RESUMEN

There is considerable interest in promoting biological nitrogen fixation (BNF) as a mechanism to reduce the inputs of nitrogenous fertilizers in agriculture, but considerable fundamental knowledge gaps still need to be addressed. BNF is catalyzed by nitrogenase, which requires a large input of energy in the form of ATP and low potential electrons. Diazotrophs that respire aerobically have an advantage in meeting the ATP demands of BNF but face challenges in protecting nitrogenase from inactivation by oxygen. Here, we constructed a genome-scale metabolic model of the nitrogen-fixing bacterium Azotobacter vinelandii, which uses a complex respiratory protection mechanism to consume oxygen at a high rate to keep intracellular conditions microaerobic. Our model accurately predicts growth rate under high oxygen and substrate concentrations, consistent with a large electron flux directed to the respiratory protection mechanism. While a partially decoupled electron transport chain compensates for some of the energy imbalance under high-oxygen conditions, it does not account for all substrate intake, leading to increased maintenance rates. Interestingly, the respiratory protection mechanism is required for accurate predictions even when ammonia is supplemented during growth, suggesting that the respiratory protection mechanism might be a core principle of metabolism and not just used for nitrogenase protection. We have also shown that rearrangement of flux through the electron transport system allows A. vinelandii to adapt to different oxygen concentrations, metal availability, and genetic disruption, which cause an ammonia excretion phenotype. Accurately determining the energy balance in an aerobic nitrogen-fixing metabolic model is required for future engineering approaches. IMPORTANCE The world's dependence on industrially produced nitrogenous fertilizers has created a dichotomy of issues. First, parts of the globe lack access to fertilizers, leading to poor crop yields that significantly limit nutrition while contributing to disease and starvation. In contrast, abundant nitrogenous fertilizers and associated overuse in large agricultural systems result in compromised soil quality and downstream environmental issues. Thus, there is considerable interest in expanding the impacts of BNF to promote improved crop yields in places struggling with access to industrial fertilizers while reducing fertilizer input in areas where overuse results in the degradation of soil health. A more robust and fundamental understanding of BNF biochemistry and microbial physiology will enable strategies to promote new and more robust associations between nitrogen-fixing microorganisms and crop plants.


Asunto(s)
Adaptación Fisiológica , Azotobacter vinelandii/metabolismo , Fijación del Nitrógeno , Nitrógeno/metabolismo , Nitrogenasa/metabolismo , Oxígeno/metabolismo , Amoníaco/metabolismo , Compuestos de Amonio/metabolismo , Azotobacter vinelandii/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Nitrogenasa/genética
15.
JAMA Netw Open ; 4(11): e2135152, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34807259

RESUMEN

Importance: The current understanding of epidemiological mechanisms and temporal trends in hospitalizations for worsening heart failure (WHF) is based on claims and national reporting databases. However, these data sources are inherently limited by the accuracy and completeness of diagnostic coding and/or voluntary reporting. Objective: To assess the overall burden of and temporal trends in the rate of hospitalizations for WHF. Design, Setting, and Participants: This cohort study, performed from January 1, 2010, to December 31, 2019, used electronic health record (EHR) data from a large integrated health care delivery system. Exposures: Calendar year trends. Main Outcomes and Measures: Hospitalizations for WHF (ie, excluding observation stays) were defined as 1 symptom or more, 2 objective findings or more including 1 sign or more, and 2 doses or more of intravenous loop diuretics and/or new hemodialysis or continuous kidney replacement therapy. Symptoms and signs were identified using natural language processing (NLP) algorithms applied to EHR data. Results: The study population was composed of 118 002 eligible patients experiencing 287 992 unique hospitalizations (mean [SD] age, 75.6 [13.1] years; 147 203 [51.1%] male; 1655 [0.6%] American Indian or Alaska Native, 28 451 [9.9%] Asian or Pacific Islander, 34 903 [12.1%] Black, 23 452 [8.1%] multiracial, 175 840 [61.1%] White, and 23 691 [8.2%] unknown), including 65 357 with a principal discharge diagnosis and 222 635 with a secondary discharge diagnosis of HF. The study population included 59 868 patients (20.8%) with HF with a reduced ejection fraction (HFrEF) (<40%), 33 361 (11.6%) with HF with a midrange EF (HFmrEF) (40%-49%), 142 347 (49.4%) with HF with a preserved EF (HFpEF) (≥50%), and 52 416 (18.2%) with unknown EF. A total of 58 042 admissions (88.8%) with a primary discharge diagnosis of HF and 62 764 admissions (28.2%) with a secondary discharge diagnosis of HF met the prespecified diagnostic criteria for WHF. Overall, hospitalizations for WHF identified on NLP-based algorithms increased from 5.2 to 7.6 per 100 hospitalizations per year during the study period. Subgroup analyses found an increase in hospitalizations for WHF based on NLP from 1.5 to 1.9 per 100 hospitalizations for HFrEF, from 0.6 to 1.0 per 100 hospitalizations for HFmrEF, and from 2.6 to 3.9 per 100 hospitalizations for HFpEF. Conclusions and Relevance: The findings of this cohort study suggest that the burden of hospitalizations for WHF may be more than double that previously estimated using only principal discharge diagnosis. There has been a gradual increase in the rate of hospitalizations for WHF with a more noticeable increase observed for HFpEF.


Asunto(s)
Prestación Integrada de Atención de Salud/estadística & datos numéricos , Progresión de la Enfermedad , Predicción/métodos , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Hospitalización/estadística & datos numéricos , Procesamiento de Lenguaje Natural , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
16.
Cancers (Basel) ; 13(20)2021 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-34680384

RESUMEN

Near-infrared phototherapy has great therapeutic potential for cancer treatment. However, for efficient application, in vivo photothermal agents should demonstrate excellent stability in blood and targeted delivery to pathological tissue. Here, we demonstrated that stable bovine serum albumin-coated gold mini nanorods conjugated to a HER2-specific designed ankyrin repeat protein, DARPin_9-29, selectively accumulate in HER2-positive xenograft tumors in mice and lead to a strong reduction in the tumor size when being illuminated with near-infrared light. The results pave the way for the development of novel DARPin-based targeted photothermal therapy of cancer.

17.
Wilderness Environ Med ; 32(2): 230-234, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33966971

RESUMEN

Remote and austere medicine can be challenging when caring for healthy individuals and requires ingenuity when managing patients with unexpected, complex disease processes, whether acute or chronic. We report the case of an adult male who presented to an isolated clinic setting with acute exacerbation of chronic liver disease. Medical management was complicated by limited transportation resources, both for supplies and patient movement. There was concern that the patient's clinical status could decompensate into a life-threatening illness that might not be adequately treated in this remote setting. Through the use of collaborative decision-making with the patient and by telemedicine consultation, the patient was successfully stabilized on the island until routine transport to a higher level of care was available. Knowledge of climbing systems and alternative transportation arrangements were integral to our ability to provide prolonged care for this patient in a remote setting. Knowledge of the use of medicinal plants was key in offsetting the side effects of other medications used. We are reminded that creative and collaborative problem-solving epitomizes wilderness and austere medicine.


Asunto(s)
Hepatopatías , Telemedicina , Ascitis/etiología , Ascitis/terapia , Edema , Humanos , Masculino , Islas del Pacífico
18.
J Inorg Biochem ; 214: 111273, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33086169

RESUMEN

Azotobacter vinelandii contains three forms of nitrogenase known as the Mo-, V-, and Fe-nitrogenases. They are all two-component enzyme systems, where the catalytic component, referred to as NifDK, VnfDGK, and AnfDGK, associates with the reductase component, the Fe protein or NifH, VnfH, and AnfH respectively. AnfDGK and VnfDGK have an additional subunit compared to NifDK, termed gamma or AnfG and VnfG, whose role is unknown. The expression of each nitrogenase is tightly regulated by metal availability, however it is known that there is crosstalk between the Mo- and V­nitrogenases but the Fe­nitrogenase components cannot support substrate reduction with its Mo­nitrogenase counterparts. Here, docking models for the nitrogenase complexes were generated in ClusPro 2.0 based on the crystal structure of the Mo­nitrogenase and refined using the HADDOCK 2.2 refinement interface to identify structural determinants that enable crosstalk between the Mo- and V­nitrogenase but not the Fe­nitrogenase. Differing salt bridge interactions were identified at the binding interface of each complex. Specifically, positively charged residues of VnfG enable complementary interactions with NifH and VnfH but not AnfH. Similarly, negatively charged residues of AnfG enable interactions with AnfH but not NifH or VnfH. A role for the G subunit is revealed where VnfG could be mediating crosstalk between the Mo- and V­nitrogenases while the AnfG subunit on AnfDGK makes interactions with NifH and VnfH unfavorable, reducing competition with NifDK and funneling electrons to the most efficient nitrogenase.


Asunto(s)
Azotobacter vinelandii/enzimología , Proteínas Bacterianas/química , Complejos Multiproteicos/química , Nitrogenasa/química
19.
J Pharm Biomed Anal ; 191: 113635, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-32998105

RESUMEN

Solanum paniculatum L. is species whose fruits are widely consumed in Brazil as a tonic beverage with higher content of steroidal saponins. In this work, we developed an analytical method for the quantification of the eight saponins present in the 70 % ethanol extract from the leaves using ultra-high-performance liquid chromatography coupled to mass spectrometry (UHPLC-MS). Besides, the eight spirostanic saponins were screened for in vitro antileishmanial activity against promastigote and amastigote forms of Leishmania (L.) amazonensis. Substances 1, 2 and 3 were found to be the most active compounds, with inhibitory concentration (IC50) values of 8.51 ± 4.38, 10.75 ± 6.85 and 10.45 ± 4.21 µM, respectively, against promastigote forms and effective concentration (EC50) values of >25, 17.73 ± 0.99 and 19.57 ± 0.84 µM, respectively, against amastigote forms. The cytotoxic test with compounds 1-3 evidenced low toxicity in murine macrophage cells, with values above 50 µM at concentration lower than 25 µM. These findings show that saponins 1-3 should be evaluated in further studies for the treatment of cutaneous leishmaniasis.


Asunto(s)
Antiprotozoarios , Saponinas , Solanum , Animales , Antiprotozoarios/toxicidad , Brasil , Concentración 50 Inhibidora , Ratones , Hojas de la Planta , Saponinas/farmacología
20.
Nat Metab ; 2(7): 603-611, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32694795

RESUMEN

The micronutrient selenium is incorporated via the selenocysteine biosynthesis pathway into the rare amino acid selenocysteine, which is required in selenoproteins such as glutathione peroxidases and thioredoxin reductases1,2. Here, we show that selenophosphate synthetase 2 (SEPHS2), an enzyme in the selenocysteine biosynthesis pathway, is essential for survival of cancer, but not normal, cells. SEPHS2 is required in cancer cells to detoxify selenide, an intermediate that is formed during selenocysteine biosynthesis. Breast and other cancer cells are selenophilic, owing to a secondary function of the cystine/glutamate antiporter SLC7A11 that promotes selenium uptake and selenocysteine biosynthesis, which, by allowing production of selenoproteins such as GPX4, protects cells against ferroptosis. However, this activity also becomes a liability for cancer cells because selenide is poisonous and must be processed by SEPHS2. Accordingly, we find that SEPHS2 protein levels are elevated in samples from people with breast cancer, and that loss of SEPHS2 impairs growth of orthotopic mammary-tumour xenografts in mice. Collectively, our results identify a vulnerability of cancer cells and define the role of selenium metabolism in cancer.


Asunto(s)
Inactivación Metabólica , Neoplasias/metabolismo , Selenio/metabolismo , Sistema de Transporte de Aminoácidos y+/metabolismo , Animales , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Supervivencia Celular , Femenino , Ferroptosis , Humanos , Ratones , Ratones Desnudos , Neoplasias/patología , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Fosfotransferasas/metabolismo , Compuestos de Selenio/metabolismo , Selenocisteína/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
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