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PURPOSE OF REVIEW: Recent research has shown the effectiveness of peripheral nerve stimulators (PNS) in managing chronic pain conditions. Ongoing studies aim to explore its potential application in treating acute postoperative pain states. The purpose of this systematic review is to assess the role of PNS in providing relief for postoperative pain. RECENT FINDINGS: Clinical studies investigating the use of peripheral nerve stimulators (PNS) for analgesia following various surgeries, such as total knee arthroplasty, anterior cruciate ligament repair, ankle arthroplasty, rotator cuff repair, hallux valgus correction, and extremity amputation, have shown promising results. Lead placement locations include the brachial plexus, sciatic, femoral, tibial, genicular, perineal, sural, radial, median, and ulnar nerves. These studies consistently report clinically significant reductions in pain scores, and some even indicate a decrease in opioid consumption following PNS for postoperative pain. PNS involves the subcutaneous placement of electrode leads to target peripheral nerve(s) followed by delivery of an electric current via an external pulse generator. While the precise mechanism is not fully understood, the theory posits that PNS modulates electrical stimulation, hindering the signaling of nociceptive pain. PNS presents itself as an alternative to opioid therapy, holding promise to address the opioid epidemic by offering a nonpharmacologic approach for both acute and chronic pain states.
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Dolor Postoperatorio , Nervios Periféricos , Humanos , Analgesia/métodos , Terapia por Estimulación Eléctrica/métodos , Manejo del Dolor/métodos , Dolor Postoperatorio/terapia , Dolor Postoperatorio/tratamiento farmacológicoRESUMEN
A short-term study was conducted to compare the effect of using poplar wood chips (PWC) instead of wheat straw (WS) litter in dairy cows. A total of 38 lactating Holstein cows (204 ± 119 days in milk, 26.9 ± 6.5 kg of milk yield [MY]) were housed in a tiestall farm for a 10-d trial including 5 d of adaptation followed by 5 sampling days (from d 5 to 10). Cows were divided into 2 homogeneous groups: one group was bedded with WS, and the second with PWC. Both litter materials were provided in the amount of 7 kg/stall per d. Each group was composed of 3 subgroups of 6 or 7 cows; the subgroups were physically separated along the feeding line by wooden boards. During the sampling days, fecal composition, used litter composition, and bacterial count (Clostridium spp., Salmonella spp., Escherichia coli, Lactobacillus, and total bacterial count) were analyzed by subgroup twice a day. On d 1 and from d 5 to 10, udder hygiene score and cow cleanliness score were also evaluated individually twice a day. Meanwhile MY, milk hygiene (total bacterial count [TBC], coliform bacterial count [CBC], and spore-forming units [SFU]) and quality were measured and analyzed from 9 animals per group. Moreover, individual animal behavior (body position and behavioral traits) and subgroup dry matter intake were measured on d 9 and 10. Fecal dry matter did not differ between groups, PWC had the lowest used litter moisture and N content favoring the highest clean cow frequency, but also gave rise to the greatest used litter microbial contamination. The MY, milk quality, TBC, SFU, and CBC were similar. The lying behavior frequency was similar between groups. However, the PWC group showed the lowest sleeping frequency, the highest frequency of other behaviors (including discomfort signs), and the lowest dry matter intake. However, despite this apparent reduction in cow comfort, no biologically important differences were observed in this short-term study between cows on PWC and WS in milk production or hygiene.
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Lactancia , Leche , Femenino , Bovinos , Animales , Triticum , Madera , Conducta Animal , Higiene , Dieta/veterinariaRESUMEN
Mortality rates following major lower extremity amputations (LEAs) 30 days-365 days postoperative have decreased, but 5-year rates remain high at 40.4%-70%. These data may not reflect recent advances in peripheral arterial disease (PAD) care, and comorbidities of chronic PAD may lead to mortality more frequently than the amputation itself. Mortality rates between diabetic and nondiabetic patients were also analyzed. Methods: The California Office of Statewide Health Planning and Development hospital database was queried for patients admitted January 1, 2007-December 31, 2018. ICD-9-CM codes identified patients with vascular disease and an amputation procedure. Results: There were 26,669 patients. The 30-day, 90-day, 1-year, and 5-year major LEA mortality rates were 4.82%, 8.62%, 12.47%, and 18.11%, respectively. Weighted averages of 30-day, 90-day, 1-year, and 5-year major LEA mortality rates in the literature are 13%, 15.40%, 47.93%, and 60.60%, respectively. Mortality risk associated with vascular disease after amputation (hazard ratio = 22.07) was 11 times greater than risk associated with amputation-specific complications from impaired mobility (hazard ratio = 1.90; P < 0.01). Having diabetes was associated with lower mortality at 30 days, 90 days, and 1 year (P < 0.01) but not at 5 years (P = 0.22). Conclusions: This study suggests that people may be living longer after their major LEA than was previously thought. This study suggests that patients' PAD may play a bigger role in contributing to their mortality than complications from loss of mobility postamputation. Although having diabetes was associated with lower postamputation mortality, the difference was no longer significant by 5 years.
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Integrating a pharmacist into a hemodialysis unit significantly reduced medication discrepancies and medication-related problems over time.Medication reconciliation for the Centers for Medicare and Medicaid Services End-Stage Renal Disease Quality Incentive Program can be optimally performed by a dialysis pharmacist.
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Conciliación de Medicamentos , Farmacéuticos , Anciano , Unidades de Hemodiálisis en Hospital , Humanos , Medicare , Errores de Medicación/prevención & control , Diálisis Renal , Estados UnidosRESUMEN
PURPOSE: To characterize perceptions of ethics among interventional radiologists to guide the development of an applied, specialty-specific approach to ethics. MATERIALS AND METHODS: A 17-question survey on perceptions of ethics and use of ethics resources was developed and vetted via cognitive interviewing of 15 diverse, representative members of the target population. The survey was distributed via the Society of Interventional Radiology, receiving 685 responses (48% participation and 90% completion rates). Responses were compared between different demographics, and common themes from free text responses were identified via content analysis. RESULTS: Most respondents indicated ethics is important for IR (93%) and more focus on practical approaches to ethical issues is needed (73%). Various ethical issues were perceived to be important for IR, but differentiating palliative from futile care was ranked as the top ethical issue. Trainees had more ethics training (P=0.05) but less confidence in navigating ethical issues (P<0.01). Regardless of career stage, those with ethics training (44%) were more confident in navigating ethical issues (P<0.01). Use of resources such as information sheets for patients and resources for coping with complications were variable and limited by lack of availability or knowledge of such resources in IR. CONCLUSIONS: Interventional radiologists believe ethics is important and face diverse ethical issues, but they are challenged by variable experiences and access to practical tools to navigate these challenges.
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Radiólogos , Radiología Intervencionista , Humanos , Encuestas y CuestionariosRESUMEN
The respiratory virus responsible for coronavirus disease 2019 (COVID-19), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has affected nearly every aspect of life worldwide, claiming the lives of over 3.9 million people globally, at the time of this publication. Neutralizing humanized nanobody (VHH)-based antibodies (VHH-huFc) represent a promising therapeutic intervention strategy to address the current SARS-CoV-2 pandemic and provide a powerful toolkit to address future virus outbreaks. Using a synthetic, high-diversity VHH bacteriophage library, several potent neutralizing VHH-huFc antibodies were identified and evaluated for their capacity to tightly bind to the SARS-CoV-2 receptor-binding domain, to prevent binding of SARS-CoV-2 spike (S) to the cellular receptor angiotensin-converting enzyme 2, and to neutralize viral infection. Preliminary preclinical evaluation of multiple VHH-huFc antibody candidates demonstrate that they are prophylactically and therapeutically effective in vivo against wildtype SARS-CoV-2. The identified and characterized VHH-huFc antibodies described herein represent viable candidates for further preclinical evaluation and another tool to add to our therapeutic arsenal to address the COVID-19 pandemic.
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Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19 , SARS-CoV-2/inmunología , Anticuerpos de Dominio Único/inmunología , HumanosRESUMEN
The opioid crisis is a national health emergency with immense morbidity, mortality, and socioeconomic cost. Emergency department (ED) pain management is tightly linked to the issue of opioid use disorder (OUD), because opioid exposure is necessary for development of OUD. Emergency nurses are on the frontlines of this complex problem, yet little, if any, attention has been paid to the role they play in the prevention and management of either pain or OUD in this unique and important setting. A framework that conceptualizes and optimizes emergency nurses as change agents in the opioid epidemic is urgently needed. While ED pain management and OUD prevention is dependent on the entire care team, this innovative study qualitatively characterizes emergency nurse perceptions of pain management, OUD prevention, and their potential role in each. Content analysis produced 14 categories that were clustered into two themes, "nurses influence ED pain management" and "adjustments in ED pain management", and an overarching message that "pain management depends on the care team." By generating a more comprehensive and nuanced understanding of the role played by emergency nurses, our findings provide essential insights into potential interventions and frameworks.
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Analgésicos Opioides , Trastornos Relacionados con Opioides , Analgésicos Opioides/efectos adversos , Servicio de Urgencia en Hospital , Humanos , Epidemia de Opioides , Dolor/tratamiento farmacológicoRESUMEN
Bone healing is a complex, well-organized process. Multiple factors regulate this process, including growth factors, hormones, cytokines, mechanical stimulation, and aging. One of the most important signaling pathways that affect bone healing is the Notch signaling pathway. It has a significant role in controlling the differentiation of bone mesenchymal stem cells and forming new bone. Interventions to enhance the healing of critical-sized bone defects are of great importance, and stem cell transplantations are eminent candidates for treating such defects. Understanding how Notch signaling impacts pluripotent stem cell differentiation can significantly enhance osteogenesis and improve the overall healing process upon transplantation. In Rancourt's lab, mouse embryonic stem cells (ESC) have been successfully differentiated to the osteogenic cell lineage. This study investigates the role of Notch signaling inhibition in the osteogenic differentiation of mouse embryonic and induced pluripotent stem cells (iPS). Our data showed that Notch inhibition greatly enhanced the differentiation of both mouse embryonic and induced pluripotent stem cells.
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Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Diferenciación Celular/efectos de los fármacos , Osteogénesis/genética , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/efectos de los fármacos , Animales , Huesos/metabolismo , Proteínas de Ciclo Celular/genética , Diferenciación Celular/fisiología , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Dexametasona/farmacología , Diaminas/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/fisiología , Mesodermo/citología , Ratones , Células Madre Embrionarias de Ratones/citología , Células Madre Embrionarias de Ratones/efectos de los fármacos , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteoblastos/fisiología , Osteogénesis/efectos de los fármacos , Células Madre Pluripotentes/metabolismo , Receptores Notch/metabolismo , Tiazoles/farmacología , Factor de Transcripción HES-1/genética , Vitamina D/farmacologíaRESUMEN
The respiratory virus responsible for Coronavirus disease 2019 (COVID-19), Severe acute respiratory syndrome coronavirus 2 (SARS-2), has impacted nearly every aspect of life worldwide, claiming the lives of over 2.5 million people globally, at the time of this publication. Neutralizing nanobodies (VHH) represent a promising therapeutic intervention strategy to address the current SARS-2 pandemic and provide a powerful toolkit to address future virus outbreaks. Using a synthetic, high-diversity VHH bacteriophage library, several potent neutralizing VHH antibodies were identified and evaluated for their capacity to tightly bind to the SARS-2 receptor-binding domain (RBD), to prevent binding of SARS-2 spike (S) to the cellular receptor Angiotensin-converting enzyme 2 (ACE2), and to neutralize viral infection. Preliminary preclinical evaluation of multiple nanobody candidates demonstrate that they are prophylactically and therapeutically effective in vivo against wildtype SARS-2. The identified and characterized nanobodies described herein represent viable candidates for further preclinical evaluation and another tool to add to our therapeutic arsenal to address the COVID-19 pandemic. Author SummaryTo fully address the on-going pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-2), it will be important to have both vaccines and therapeutic strategies to prevent and mitigate the effects of SARS-2. In this study, we describe the identification and characterization of potently neutralizing humanized single domain heavy chain (VHH) antibodies that have binding affinity for both the original Wuhan strain and widely circulating B.1.1.7/UK strain. VHH antibodies have the same therapeutic potential as conventional antibodies in half the size and with greater stability and solubility. Using a synthetic humanized high-diversity VHH phage library we identified several candidates with strong affinity for the SARS-2 spike that block the interaction of SARS-2 spike with the cellular receptor ACE2, and effectively neutralize infection with SARS-2 in vitro. By sequencing viral escape mutants generated in the presence of each VHH we mapped the binding sites of the VHH antibodies and assessed their affinity against newly emerging SARS-2 variants. Finally, we demonstrate that two of these VHH antibodies show prophylactic and therapeutic efficacy in vivo against challenge with SARS-2. This study establishes that screening highly diverse VHH phage libraries against viral threats can yield highly effective therapeutic agents in real time.
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Excessive urination can be a perioperative challenge for providers due to the possibility of secondary hypernatremia. Dexmedetomidine has previously been reported by several groups to induce a polyuric-like syndrome; however, the exact mechanism in humans remains unclear. In this report, we discuss a case of intraoperative, transient dexmedetomidine bolus-induced excessive urination and suggest a potential mechanism by which this may occur in a subset of the population.
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Osteoarthritis (OA) is a painful and debilitating disease characterized by the chronic and progressive degradation of articular cartilage. Post-traumatic OA (PTOA) is a secondary form of OA that develops in ~50% of cases of severe articular injury. Inflammation and re-occurring injury have been implicated as contributing to the progression of PTOA after the initial injury. However, there is very little known about external factors prior to injury that could affect the risk of PTOA development. To examine how the gut microbiome affects PTOA development we used a chronic antibiotic treatment regimen starting at weaning for six weeks prior to ACL rupture, in mice. A six-weeks post-injury histological examination showed more robust cartilage staining on the antibiotic (AB)-treated mice than the untreated controls (VEH), suggesting slower disease progression in AB cohorts. Injured joints also showed an increase in the presence of anti-inflammatory M2 macrophages in the AB group. Molecularly, the phenotype correlated with a significantly lower expression of inflammatory genes Tlr5, Ccl8, Cxcl13, and Foxo6 in the injured joints of AB-treated animals. Our results indicate that a reduced state of inflammation at the time of injury and a lower expression of Wnt signaling modulatory protein, Rspo1, caused by AB treatment can slow down or improve PTOA outcomes.
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Lesiones del Ligamento Cruzado Anterior/complicaciones , Antibacterianos/farmacología , Cartílago Articular/lesiones , Microbioma Gastrointestinal/efectos de los fármacos , Inflamación/tratamiento farmacológico , Osteoartritis/prevención & control , Animales , Lesiones del Ligamento Cruzado Anterior/patología , Progresión de la Enfermedad , Inflamación/etiología , Inflamación/patología , Ratones , Ratones Endogámicos C57BL , Osteoartritis/etiología , Osteoartritis/metabolismo , Osteoartritis/patología , Fenotipo , RNA-Seq , TranscriptomaRESUMEN
For decades, oxidative dearomatization has been employed as a key step in the synthesis of complex molecules. Challenges in controlling the chemo- and site-selectivity of this transformation have sparked the development of a variety of specialized oxidants; however, these result in stoichiometric amounts of organic byproducts. Herein, we describe a photocatalytic method for oxidative dearomatization using molecular oxygen as the stoichiometric oxidant. This provides environmentally benign entry to highly substituted o-quinols, reactive intermediates which can be elaborated to a number of natural product families.
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Benzaldehídos/química , Hidroquinonas/síntesis química , Catálisis , Hidroquinonas/química , Oxidantes Fotoquímicos/química , Oxidación-Reducción , Procesos FotoquímicosRESUMEN
Osteoarthritis (OA) is a degenerative disease of the hyaline articular cartilage. This disease is progressive and may lead to disability. Researchers proposed many regenerative approaches to treat osteoarthritis, including stem cells. Trans-differentiation of a fully differentiated cell state directly into another different differentiated cell state avoids the disadvantages of fully reprogramming cells to induced pluripotent stem cells (iPSCs) in terms of faster reprogramming of the needed cells. Trans-differentiation also reduces the risk of tumor formation by avoiding the iPSC state. OSKM factors (Oct4, Sox2, Klf4, and cMyc) accompanied by the JAK-STAT pathway inhibition, followed by the introduction of specific differentiation factors, directly reprogrammed mouse embryonic fibroblasts to chondroblasts. Our results showed the absence of intermediate induced pluripotent stem cell formation. The resulting aggregates showed clear hyaline and hypertrophic cartilage. Tumor formation was absent in sub-cutaneous capsules transplanted in SCID mice.
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Transdiferenciación Celular/efectos de los fármacos , Reprogramación Celular , Condrocitos/citología , Citocinas/farmacología , Fibroblastos/citología , Quinasas Janus/antagonistas & inhibidores , Animales , Biomarcadores/metabolismo , Huesos/metabolismo , Reprogramación Celular/efectos de los fármacos , Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Condrogénesis/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Glicosaminoglicanos/metabolismo , Cartílago Hialino/efectos de los fármacos , Cartílago Hialino/metabolismo , Cartílago Hialino/patología , Hipertrofia , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/metabolismo , Quinasas Janus/metabolismo , Cinética , Factor 4 Similar a Kruppel , Ratones SCID , Modelos Biológicos , Inhibidores de Proteínas Quinasas/farmacología , Factores de Transcripción/metabolismoRESUMEN
Generation of reactive intermediates and interception of these fleeting species under physiological conditions is a common strategy employed by Nature to build molecular complexity. However, selective formation of these species under mild conditions using classical synthetic techniques is an outstanding challenge. Here, we demonstrate the utility of biocatalysis in generating o-quinone methide intermediates with precise chemoselectivity under mild, aqueous conditions. Specifically, α-ketoglutarate-dependent non-heme iron enzymes, CitB and ClaD, are employed to selectively modify benzylic C-H bonds of o-cresol substrates. In this transformation, biocatalytic hydroxylation of a benzylic C-H bond affords a benzylic alcohol product which, under the aqueous reaction conditions, is in equilibrium with the corresponding o-quinone methide. o-Quinone methide interception by a nucleophile or a dienophile allows for one-pot conversion of benzylic C-H bonds into C-C, C-N, C-O, and C-S bonds in chemoenzymatic cascades on preparative scale. The chemoselectivity and mild nature of this platform is showcased here by the selective modification of peptides and chemoenzymatic synthesis of the chroman natural product (-)-xyloketal D.
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Indolquinonas/biosíntesis , Proteínas de Hierro no Heme/metabolismo , Indolquinonas/química , Estructura Molecular , Monascus/enzimología , Proteínas de Hierro no Heme/química , Penicillium/enzimología , EstereoisomerismoRESUMEN
Selective access to a targeted isomer is often critical in the synthesis of biologically active molecules. Whereas small-molecule reagents and catalysts often act with anticipated site- and stereoselectivity, this predictability does not extend to enzymes. Further, the lack of access to catalysts that provide complementary selectivity creates a challenge in the application of biocatalysis in synthesis. Here, we report an approach for accessing biocatalysts with complementary selectivity that is orthogonal to protein engineering. Through the use of a sequence similarity network (SSN), a number of sequences were selected, and the corresponding biocatalysts were evaluated for reactivity and selectivity. With a number of biocatalysts identified that operate with complementary site- and stereoselectivity, these catalysts were employed in the stereodivergent, chemoenzymatic synthesis of azaphilone natural products. Specifically, the first syntheses of trichoflectin, deflectin-1a, and lunatoic acid A were achieved. In addition, chemoenzymatic syntheses of these azaphilones supplied enantioenriched material for reassignment of the absolute configuration of trichoflectin and deflectin-1a based on optical rotation, CD spectra, and X-ray crystallography.
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Benzopiranos/síntesis química , Productos Biológicos/síntesis química , Pigmentos Biológicos/síntesis química , Benzopiranos/química , Biocatálisis , Productos Biológicos/química , Pigmentos Biológicos/química , EstereoisomerismoRESUMEN
The aim of this study was to quantify the major sources of variation in the levels of 15 minerals in individual milk samples collected from cows raised in multibreed dairy herds. The herds (n = 27) were classified into 2 categories, according to milk productivity. Milk productivity was based on the net energy of lactating cows' average daily milk yield. Milk samples were collected from 240 cows of 6 different breeds: 3 specialized dairy (Holstein-Friesian, Brown Swiss, and Jersey) and 3 dual-purpose (Simmental, Rendena, and Alpine Grey). The samples were analyzed for macro-elements (Na, Mg, P, S, K, and Ca), essential micro-elements (Mn, Fe, Cu, Zn, and Se), and environmental micro-elements (B, Si, Sr, and Sn), using inductively coupled plasma-optical emission spectrometry. Data were analyzed using a linear mixed model that included fixed effects of days in milk (DIM), parity, breed, and herd productivity, and a random effect of herd-date within productivity level. Results showed that the effect of herd-date varied across minerals. It was especially large for environmental minerals (ranging from 47 to 91% of total variance) and ranged from 11 to 61% for macrominerals and essential microminerals. Milk samples collected from farms with a high level of herd productivity had a richer mineral profile than samples from low-productivity herds. Parity only influenced macrominerals, with the exception of S and Ca, while DIM influenced almost all minerals, with a few exceptions among the environmental elements. Differences in mineral profile were small between specialized and dual-purpose breeds, but they were large within the group of the specialized cows. These breed differences were reduced after adjusting for milk quality and yield, particularly in the case of milk Mg, S, Ca, Mn, and Zn levels. Milk samples from the Jersey and Brown Swiss cows had higher mineral levels (Sn excluded) than milk from the Holstein-Friesian cows; the other breeds of Alpine origin produced milk of intermediate quality. Our findings suggest that breed has a stronger effect on macrominerals and some of the essential microminerals than herd productivity, parity, and DIM. The modification of the mineral profile in milk seems possible for many minerals, but it likely depends on genetics (e.g., breed, selection) and on environmental and management factors in variable proportions according to the mineral considered.
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Bovinos/fisiología , Lactancia/fisiología , Leche/química , Minerales/análisis , Animales , Cruzamiento , Bovinos/clasificación , Industria Lechera/métodos , Granjas , Femenino , Modelos Lineales , Leche/metabolismo , Minerales/clasificación , Paridad , EmbarazoRESUMEN
Biocatalytic reactions embody many features of ideal chemical transformations, including the potential for impeccable selectivity, high catalytic efficiency, mild reaction conditions and the use of environmentally benign reagents. These advantages have created a demand for biocatalysts that expand the portfolio of complexity-generating reactions available to synthetic chemists. However, the tradeoff that often exists between the substrate scope of a biocatalyst and its selectivity limits the application of enzymes in synthesis. We recently demonstrated that a flavin-dependent monooxygenase, TropB, maintains high levels of site- and stereoselectivity across a range of structurally diverse substrates. Herein, we disclose the structural basis for substrate binding in TropB, which performs a synthetically challenging asymmetric oxidative dearomatization reaction with exquisite site- and stereoselectivity across a range of phenol substrates, providing a foundation for future protein engineering and reaction development efforts. Our hypothesis for substrate binding is informed by a crystal structure of TropB and molecular dynamics simulations with the corresponding computational TropB model and is supported by experimental data. In contrast to canonical class A FAD-dependent monooxygenases in which substrates bind in a protonated form, our data indicate that the phenolate form of the substrate binds in the active site. Furthermore, the substrate position is controlled through twopoint binding of the phenolate oxygen to Arg206 and Tyr239, which are shown to have distinct and essential roles in catalysis. Arg206 is involved in the reduction of the flavin cofactor, suggesting a role in flavin dynamics. Further, QM/MM simulations reveal the interactions that govern the facial selectivity that leads to a highly enantioselective transformation. Thus, the structural origins of the high levels of site-and stereoselectivity observed in reactions of TropB across a range of substrates are elucidated, providing a foundation for future protein engineering and reaction development efforts.
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The diverse chemistry possible with flavin cofactors positions flavin-dependent enzymes as versatile synthetic tools. This focused review highlights applications of flavin-dependent enzymes in organic synthesis. Select examples of monoamine oxidases, ene-reductases, monooxygenases and halogenases in target-oriented synthesis are presented.
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Background: Colorectal cancer (CRC) is among the leading cancer diagnoses affecting both men and women worldwide. Prevention and early detection of CRC is possible by increasing access to and utilisation of screening tests. Although CRC screening is highly recommended, screening rates remain suboptimal in the USA, particularly among underserved populations. Our project site, an urban federally qualified health centre, was not meeting the national screening target of 80% of eligible adults. Objective: The aim of this quality improvement project was to increase the number of orders for CRC screening to eligible patients by using unlicensed assistive personnel and automated telephone outreach calls to offer 100 patients CRC screening during an 8-week period. Methods: 40 patients received outreach calls from care coordinators (CC). 40 patients received automated telephone call reminders to call a CC to obtain an order for CRC screening. 20 patients were offered CRC screening by a medical assistant (MA) as part of their scheduled office visits. We used two plan-do-study-act (PDSA) cycles to deliver these three screening interventions. Results: A total of 100 patients received one of the interventions. Ten of those patients received an order for either colonoscopy or faecal immunochemical testing by the conclusion of the second PDSA cycle. The MA-offered screening resulted in the highest percentage of patients accepting CRC screenings and patients preferred this outreach approach compared with CC outreach or automated voice messages. CC outreach yielded a lower rate of accepted screenings. None of the patients who received the automated calls followed up to obtain a screening order. Conclusion: Our project demonstrates that unlicensed assistive personnel have the potential to increase patient access to CRC screening.
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Neoplasias Colorrectales/diagnóstico , Personal de Salud/normas , Tamizaje Masivo/normas , Cuidados Posteriores/métodos , Cuidados Posteriores/normas , Cuidados Posteriores/estadística & datos numéricos , Neoplasias Colorrectales/diagnóstico por imagen , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/normas , Detección Precoz del Cáncer/estadística & datos numéricos , Personal de Salud/psicología , Personal de Salud/estadística & datos numéricos , Humanos , Entrevistas como Asunto/métodos , Entrevistas como Asunto/normas , Entrevistas como Asunto/estadística & datos numéricos , Tamizaje Masivo/métodos , Tamizaje Masivo/estadística & datos numéricos , Sangre Oculta , Aceptación de la Atención de Salud/psicología , Aceptación de la Atención de Salud/estadística & datos numéricos , Mejoramiento de la Calidad , Clase SocialRESUMEN
Biocatalysts have the potential to perform reactions with exceptional selectivity and high catalytic efficiency while utilizing safe and sustainable reagents. Despite these positive attributes, the utility of a biocatalyst can be limited by the breadth of substrates that can be accommodated in the active site in a reactive pose. Proven strategies exist for optimizing the performance of a biocatalyst toward unnatural substrates, including protein engineering; however, these methods can be time intensive and require specialized equipment that renders these approaches inaccessible to synthetic chemists. Strategies accessible to chemists for the expansion of a natural enzyme's substrate scope, while maintaining high levels of site- and stereoselectivity, remain elusive. Here, we employ a computationally guided substrate engineering strategy to expand the synthetic utility of a flavin-dependent monooxygenase. Specifically, experimental observations and computational modeling led to the identification of a critical interaction between the substrate and protein which is responsible for orienting the substrate in a pose productive for catalysis. The fundamental hypothesis for this positioning group strategy is supported by binding and kinetic assays as well as computational studies with a panel of compounds. Further, incorporation of this positioning group into substrates through a cleavable ester linkage transformed compounds not oxidized by the biocatalyst SorbC into substrates efficiently oxidatively dearomatized by the wild-type enzyme with the highest levels of site- and stereoselectivity known for this transformation.