RESUMEN
The quality of drug products in the United States has been a matter of growing concern. Buyers and payers of pharmaceuticals have limited insight into measures of drug-product quality. Therefore, a quality-score system driven by data collection is proposed to differentiate between the qualities of drug products produced by different manufacturers. The quality scores derived using this proposed system would be based upon public regulatory data and independently-derived chemical data. A workflow for integrating the system into procurement decisions within health care organizations is also suggested. The implementation of such a quality-score system would benefit health care organizations by including the consideration of the quality of products while also considering price as a part of the drug procurement process. Such a system would also benefit the U.S. health care industry by bringing accountability and transparency into the drug supply chain and incentivizing manufacturers to place an increased emphasis on the quality and safety of their drug products.
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Industria Farmacéutica , Sector de Atención de Salud , Humanos , Estados UnidosRESUMEN
BACKGROUND: Donor site complications are a significant source of morbidity for patients undergoing abdominal-based free flap breast reconstruction, but there is a paucity of data regarding minimizing these postoperative complications. We hypothesize that selective ablation of the umbilicus at the time of deep inferior epigastric perforator (DIEP) harvest decreases the incidence of umbilical and abdominal wall complications in high-risk patients. METHODS: A retrospective review was performed of all patients (n = 117) who underwent DIEP harvest with concomitant umbilical ablation from 2010 to 2015. This cohort was paired with 117 patients who underwent DIEP harvest without umbilical ablation. Preoperative risk factors, intraoperative factors, and postoperative complications were compared. RESULTS: The umbilical ablation group had significantly higher body mass index (30.9 vs 27.4 kg/m, P < 0.001), presence of umbilical scar (20.9% vs 5.3%, P < 0.001), umbilical hernia (82.9% vs 8.5% P < 0.001), ventral hernia (23.9% vs 1.7%, P < 0.001), and rectus diastasis (10.3% vs 2.6%, P = 0.016). There were no significant differences of smoking, diabetes mellitus, hypertension, prior abdominal surgery, or midline abdominal scar. The umbilical ablation group had a significantly lower rate of postoperative abdominal wound dehiscence and skin loss (11.1% vs 22.2%, P = 0.023) and overall donor site complications (24.8% vs 39.3%, P = 0.017). There was no significant difference in incidence of cellulitis, seroma, or abscess. Mean follow-up time was 1.8 years. CONCLUSIONS: Selective umbilical ablation in high-risk patients at the time of abdominal flap harvest can result in significantly fewer donor site wound complications, even in the setting of increased risk factors for poor wound healing. This is likely due to avoidance of umbilical incisions and decreased upper abdominal skin undermining. We conclude that umbilical ablation is a viable option to minimize donor site complications, especially in high-risk patients.
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Mamoplastia , Colgajo Perforante , Arterias Epigástricas , Humanos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos , Seroma , Ombligo/cirugíaRESUMEN
BACKGROUND: Evidence from cancer clinical trials has strong internal validity but can be difficult to generalize to real-world patient populations. Here we analyzed real-world outcomes of patients with metastatic non-small cell lung cancer (mNSCLC) treated with programmed cell death protein 1 (PD-1) inhibitors in the first year following U.S. regulatory approval. MATERIALS AND METHODS: This retrospective study leveraged electronic health record (EHR) data collected during routine patient care in community cancer care clinics. The cohort included patients with mNSCLC who had received nivolumab or pembrolizumab for metastatic disease (n = 1,344) with >1 EHR-documented visit from January 1, 2011, to March 31, 2016. Patients with a > 90-day gap between advanced disease diagnosis and first EHR structured data entry were excluded. RESULTS: Estimated median overall survival (OS) was 8.0 months (95% confidence interval 7.4-9.0 months). Estimated median OS was 4.7 months (3.4-6.6) for patients with anaplastic lymphoma kinase rearrangement- and epidermal growth factor receptor mutation-positive tumors, and 8.6 months (7.7-10.6) for patients without such mutations. Age at PD-1 inhibitor initiation or line of therapy did not impact OS. CONCLUSION: This analysis suggests OS in real-world patients may be shorter than in conventional clinical trial patient cohorts, potentially due to narrow trial eligibility criteria. The lack of difference in OS by line of therapy or age at immunotherapy initiation suggests sustained benefit of PD-1 inhibitors in multitreated patients with mNSCLC and that age is not a predictor of outcome. Further studies are underway in patients with comorbidities, organ dysfunction, and multiple prior therapies. IMPLICATIONS FOR PRACTICE: This study evaluated data derived from electronic health records of patients with metastatic non-small cell lung cancer treated with programmed cell death protein 1 (PD-1) inhibitors in the year following regulatory approval. This real-world cohort had shorter overall survival (OS) indexed to PD-1 inhibitor initiation than reported in clinical trials. Late-line treatment did not influence OS, and patients aged >75 at immunotherapy initiation did not have worse outcomes than younger patients. As new therapies enter clinical practice, real-world data can complement clinical trial evidence providing information on generalizability and helping inform clinical treatment decisions.
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Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Análisis de Supervivencia , Estados UnidosRESUMEN
BACKGROUND: Evidence from cancer clinical trials can be difficult to generalize to real-world patient populations, but can be complemented by real-world evidence to optimize personalization of care. Further, real-world usage patterns of programmed cell death protein 1 (PD-1) inhibitors following approval can inform future studies of subpopulations underrepresented in clinical trials. MATERIALS AND METHODS: We performed a multicenter analysis using electronic health record data collected during routine care of patients treated in community cancer care clinics in the Flatiron Health network. Real-world metastatic non-small cell lung cancer (NSCLC) patients who received nivolumab or pembrolizumab in the metastatic setting (n = 1,344) were selected from a starting random sample of 55,969 NSCLC patients with two or more documented visits from January 1, 2011, through March 31, 2016. The primary study outcome measurement was demographic and treatment characteristics of the cohort. RESULTS: Median age at PD-1 inhibitor initiation was 69 years (interquartile range 61-75). Patients were 56% male, 88% smokers, 65% nonsquamous histology, and 64% diagnosed at stage IV. Of 1,344 patients, 112 (8%) were tested for programmed death-ligand 1 expression. Overall, 50% received nivolumab or pembrolizumab in the second line, with a substantial proportion of third and later line use that began to decline in Q4 2015. CONCLUSION: During the year following U.S. regulatory approval of PD-1 inhibitors for treatment of NSCLC, real-world patients receiving nivolumab or pembrolizumab were older at treatment initiation and more had smoking history relative to clinical trial cohorts. Studies of outcomes in underrepresented subgroups are needed to inform real-world treatment decisions. IMPLICATIONS FOR PRACTICE: Evidence gathered in conventional clinical trials used to assess safety and efficacy of new therapies is not necessarily generalizable to real-world patients receiving these drugs following regulatory approval. Real-world evidence derived from electronic health record data can yield complementary evidence to enable optimal clinical decisions. Examined here is a cohort of programmed cell death protein 1 inhibitor-treated metastatic non-small cell lung cancer patients in the first year following regulatory approval of these therapies in this indication. The analysis revealed how the real-world cohort differed from the clinical trial cohorts, which will inform which patients are underrepresented and warrant additional studies.
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Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Nivolumab/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antígeno B7-H1/metabolismo , Biomarcadores de Tumor/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Registros Electrónicos de Salud/estadística & datos numéricos , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pautas de la Práctica en MedicinaRESUMEN
We report here the design and synthesis of a novel series of benzylamines that are potent and selective inhibitors of uPA with promising oral availability in rat. Further evaluation of one representative (ZK824859) of the new structural class showed that this compound lowered clinical scores when dosed in either acute or chronic mouse EAE models, suggesting that uPA inhibitors of this type could be useful for the treatment of multiple sclerosis.
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Bencilaminas/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Inhibidores de Serina Proteinasa/uso terapéutico , Activador de Plasminógeno de Tipo Uroquinasa/antagonistas & inhibidores , Animales , Bencilaminas/síntesis química , Bencilaminas/química , Bencilaminas/farmacocinética , Sitios de Unión , Femenino , Humanos , Ratones , Modelos Moleculares , Estructura Molecular , Ratas , Inhibidores de Serina Proteinasa/síntesis química , Inhibidores de Serina Proteinasa/química , Inhibidores de Serina Proteinasa/farmacocinética , Relación Estructura-Actividad , Activador de Plasminógeno de Tipo Uroquinasa/químicaRESUMEN
The seminal importance of DNA sequencing to the life sciences, biotechnology and medicine has driven the search for more scalable and lower-cost solutions. Here we describe a DNA sequencing technology in which scalable, low-cost semiconductor manufacturing techniques are used to make an integrated circuit able to directly perform non-optical DNA sequencing of genomes. Sequence data are obtained by directly sensing the ions produced by template-directed DNA polymerase synthesis using all-natural nucleotides on this massively parallel semiconductor-sensing device or ion chip. The ion chip contains ion-sensitive, field-effect transistor-based sensors in perfect register with 1.2 million wells, which provide confinement and allow parallel, simultaneous detection of independent sequencing reactions. Use of the most widely used technology for constructing integrated circuits, the complementary metal-oxide semiconductor (CMOS) process, allows for low-cost, large-scale production and scaling of the device to higher densities and larger array sizes. We show the performance of the system by sequencing three bacterial genomes, its robustness and scalability by producing ion chips with up to 10 times as many sensors and sequencing a human genome.
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Genoma Bacteriano/genética , Genoma Humano/genética , Genómica/instrumentación , Genómica/métodos , Semiconductores , Análisis de Secuencia de ADN/instrumentación , Análisis de Secuencia de ADN/métodos , Escherichia coli/genética , Humanos , Luz , Masculino , Rhodopseudomonas/genética , Vibrio/genéticaRESUMEN
Very Late Antigen-4 (VLA-4, α4ß1-integrin, ITGA4) orchestrates cell-cell and cell-endothelium adhesion. Given the proposed role of VLA-4 in sickle cell disease (SCD) pathophysiology, we evaluated the ability of the VLA-4 blocking antibody natalizumab to inhibit SCD blood cell adhesion. Natalizumab recognized surface VLA-4 on leucocytes and reticulocytes in whole blood from SCD subjects. SCD reticulocytes were positive for VLA-4, while VLA-4 staining of non-SCD reticulocytes was undetectable. Titrations with natalizumab revealed the presence of saturable levels of VLA-4 on both SCD reticulocytes and leucocytes similar to healthy subject leucocytes. Under physiological flow conditions, the adhesion of SCD whole blood cells and isolated SCD leucocytes to immobilized vascular cell adhesion molecule 1 (VCAM-1) was blocked by natalizumab in a dose-dependent manner, which correlated with cell surface receptor binding. Natalizumab also inhibited >50% of whole blood cell binding to TNF-α activated human umbilical vein endothelial cell monolayers under physiological flow at clinically relevant concentrations (10 to 100 µg/ml). This indicates that VLA-4 is the dominant receptor that drives SCD reticulocyte and mononuclear cell adhesion to VCAM-1 and that the VLA-4 adhesion to VCAM-1 is a significant contributor to SCD blood cell adhesion to endothelium. Thus, VLA-4 blockade may be beneficial in sickle cell disease.
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Anemia de Células Falciformes/sangre , Adhesión Celular/efectos de los fármacos , Integrina alfa4beta1/antagonistas & inhibidores , Leucocitos/efectos de los fármacos , Leucocitos/metabolismo , Natalizumab/farmacología , Reticulocitos/efectos de los fármacos , Reticulocitos/patología , Adolescente , Adulto , Anemia de Células Falciformes/diagnóstico , Anemia de Células Falciformes/tratamiento farmacológico , Biomarcadores , Membrana Celular/metabolismo , Niño , Preescolar , Simulación por Computador , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Femenino , Citometría de Flujo , Hemodinámica , Humanos , Inmunoglobulina G/química , Inmunoglobulina G/metabolismo , Inmunoglobulina G/farmacología , Lactante , Masculino , Persona de Mediana Edad , Natalizumab/química , Natalizumab/metabolismo , Unión Proteica , Multimerización de Proteína , Reticulocitos/metabolismo , Molécula 1 de Adhesión Celular Vascular/metabolismo , Adulto JovenRESUMEN
OBJECTIVES: Generic medications represent 90% of prescriptions in the US market and provide a tremendous financial benefit for patients. Recently, multiple generic drugs have been recalled due to the presence of carcinogens, predominantly N-nitrosodimethylamine (NDMA), including an extensive recall of extended-release (ER) metformin products in 2020. STUDY DESIGN: Primary pharmaceutical quality testing and database analysis. METHODS: We tested marketed metformin immediate-release (IR) and ER tablets from a wide sample of generic manufacturers for the presence of carcinogenic impurities NDMA and N,N-dimethylformamide (DMF). We examined the association of level of impurity with drug price and the impact of the 2020 FDA recalls on unit price and prescription fill rate. RESULTS: Postrecall NDMA levels were significantly lower in metformin ER samples (standardized mean difference = -2.0; P = .01); however, we found continued presence of carcinogens above the FDA threshold in 2 of 30 IR samples (6.67%). Overall, the presence of contaminant levels was not significantly associated with price for either IR (NDMA: R2 = 0.142; P = .981; DMF: R2 = 0.382; P = .436) or ER (NDMA: R2 = 0.124; P = .142; DMF: R2 = 0.199; P = .073) samples. Despite recalls, metformin ER prescription fills increased by 8.9% while unit price decreased by 19.61% (P < .05). CONCLUSIONS: Recalls of metformin ER medications were effective in lowering NDMA levels below the FDA threshold; however, some samples of generic metformin still contained carcinogens even after FDA-announced recalls. The absence of any correlation with price indicates that potentially safer products are available on the market for the same price as poorer-quality products.
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Metformina , Humanos , Metformina/uso terapéutico , Medicamentos Genéricos , Prescripciones , Dimetilnitrosamina/análisis , CarcinógenosRESUMEN
BACKGROUND: You only get one opportunity to make a first impression. In today's era, that first impression is frequently a digital one. The authors' old digital brand "face" was stale and not a true representation of how they view themselves as a practice. In an evolving arena of competition and surgical scope, the authors felt compelled to engage in rebranding their practice. METHODS: This article details the steps the authors took to launch a new website, generate collateral branded material, and execute a social media marketing plan. The authors attempt to keep the outline general enough to be applicable to the range of practice types of the Journal 's readership, and present relevant results of the process. RESULTS: Samples of "creative" products are shown. Quantifiable outcomes were direct website traffic (91% increase), website sessions (82% increase), unique users (55% increase), page views (118% increase), and time spent browsing (100% increase). The authors experienced a 21% increase in new patient volume and a similar increase in total cases performed. CONCLUSIONS: This article outlines steps the authors took to rebrand their practice in the face of current challenges in the plastic surgery landscape and how prospective patients seek surgeons. Benchmarking the steps of a successful branding process is crucial and informative to developing and executing a plan. Although there are many potential contributors to the growth of a practice, the impact of our branding appears to be a significant factor.
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Práctica de Grupo , Procedimientos de Cirugía Plástica , Cirugía Plástica , Humanos , Comercialización de los Servicios de Salud/métodos , Estudios ProspectivosRESUMEN
Alcohol-based hand sanitizers (ABHS) have been an important hand hygiene tool during the COVID-19 pandemic. Recently, ABHS from non-traditional drug manufacturers have entered the market, triggered by a lack of ABHS availability. Some of these ABHS contain high levels of chemical impurities that may be harmful with frequent exposure. Additionally, the use of refillable dispensers designed to accept ABHS from bulk containers allows for mixing and evaporation that may compromise ABHS integrity. To understand the risks associated with low quality ABHS and bulk refilling practices, we collected 77 ABHS samples sourced from community settings (restaurants, grocery stores, etc.) and 40 samples from a single school district. All samples were obtained from bulk refillable dispensers that were in use. Samples were analyzed for alcohol content, chemical impurities, aesthetic qualities, and presence of drug labeling information. Additionally, we performed laboratory-based experiments to determine the impact of dispenser design on alcohol evaporation rates. Over 70% of samples for which photos were available showed lack of essential labeling information, including missing "Drug Facts Labels". For ABHS samples acquired from community settings, nearly 14% of samples had visible impurities, and over 30% of samples had concentrations of acetal and acetaldehyde in excess of FDA interim limits. Subpotent ethanol concentrations were observed in 9.09% and 82.05% of samples from community settings and the school district, respectively, with the school district sample results being associated with dispenser misuse. Laboratory-based experiments show dispenser design significantly impacts the rate of ethanol evaporation of ABHS products, especially if stored in open refillable dispensers without an internal reservoir. This study demonstrates risks associated with use of inferior ABHS and bulk refilling practices. Regulatory agencies should issue guidance on best practices in community settings to ensure the integrity of ABHS as an essential public health tool to prevent the spread of COVID-19 and other transmissible diseases.
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COVID-19/prevención & control , Etanol/análisis , Desinfectantes para las Manos/análisis , Contaminación de Medicamentos/estadística & datos numéricos , Almacenaje de Medicamentos , Desinfectantes para las Manos/normas , Humanos , Etiquetado de Productos/normas , Etiquetado de Productos/estadística & datos numéricos , Control de CalidadRESUMEN
Sickle cell disease (SCD) is associated with hemolysis, vascular inflammation, and organ damage. Affected patients experience chronic painful vaso-occlusive events requiring hospitalization. Hypoxia-induced polymerization of sickle hemoglobin S (HbS) contributes to sickling of red blood cells (RBCs) and disease pathophysiology. Dilution of HbS with nonsickling hemoglobin or hemoglobin with increased oxygen affinity, such as fetal hemoglobin or HbS bound to aromatic aldehydes, is clinically beneficial in decreasing polymerization. We investigated a novel alternate approach to modify HbS and decrease polymerization by inhibiting methionine aminopeptidase 2 (MetAP2), which cleaves the initiator methionine (iMet) from Val1 of α-globin and ßS-globin. Kinetic studies with MetAP2 show that ßS-globin is a fivefold better substrate than α-globin. Knockdown of MetAP2 in human umbilical cord blood-derived erythroid progenitor 2 cells shows more extensive modification of α-globin than ß-globin, consistent with kinetic data. Treatment of human erythroid cells in vitro or Townes SCD mice in vivo with selective MetAP2 inhibitors extensively modifies both globins with N-terminal iMet and acetylated iMet. HbS modification by MetAP2 inhibition increases oxygen affinity, as measured by decreased oxygen tension at which hemoglobin is 50% saturated. Acetyl-iMet modification on ßS-globin delays HbS polymerization under hypoxia. MetAP2 inhibitor-treated Townes mice reach 50% total HbS modification, significantly increasing the affinity of RBCs for oxygen, increasing whole blood single-cell RBC oxygen saturation, and decreasing fractional flow velocity losses in blood rheology under decreased oxygen pressures. Crystal structures of modified HbS variants show stabilization of the nonpolymerizing high O2-affinity R2 state, explaining modified HbS antisickling activity. Further study of MetAP2 inhibition as a potential therapeutic target for SCD is warranted.
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Anemia de Células Falciformes , Hemoglobina Falciforme , Aminopeptidasas , Anemia de Células Falciformes/tratamiento farmacológico , Animales , Antidrepanocíticos/farmacología , Humanos , Cinética , Metaloendopeptidasas , Metionil Aminopeptidasas , Ratones , PolimerizacionRESUMEN
This work rests on responses from 219 male sexual assault and rape victims who self-reported their victimization in the 1994-1996 Violence and Threats of Violence Against Women and Men in the United States survey. The authors expected that men who reported being severely assaulted would be more likely than others to seek counseling. They defined severely assaulted as having been penetrated, assaulted with a weapon, threatened, self-reported sustaining physical injuries, sought medical care, and/or reported the assault to the police. However, in their logistic model that explores who sought counseling, only one variable was significant. The odds of seeking counseling for men who reported being penetrated had significantly lower odds of seeking counseling all else equal.
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Consejo/métodos , Víctimas de Crimen/psicología , Conocimientos, Actitudes y Práctica en Salud , Aceptación de la Atención de Salud/psicología , Violación/psicología , Sobrevivientes/psicología , Adulto , Víctimas de Crimen/rehabilitación , Emociones , Humanos , Masculino , Salud del Hombre , Violación/rehabilitación , Trastornos por Estrés Postraumático/rehabilitación , Encuestas y Cuestionarios , Adulto JovenRESUMEN
UNLABELLED: To optimize in vivo tissue uptake kinetics and clearance of engineered monoclonal antibody (mAb) fragments for radiotherapeutic and radiodiagnostic applications, we compared the biodistribution and tumor localization of four (111)In- and (86)Y-labeled antibody formats, derived from a single antimindin/RG-1 mAb, in a prostate tumor model. The IgG, diabody, single-chain variable domain (scFv), and novel miniantibody formats, composed of the human IgE-C(H)4 and a modified IgG1 hinge linked to scFv domains, were compared. METHODS: Antibodies were first derivatized with the bifunctional chelator CHX-A''-diethylenetriamine pentaacetic acid and then bound to the radiometal to create radiolabeled immunoconjugates. Human LNCaP xenografts were grown in nude mice, and (111)In- or (86)Y-labeled antibodies were administered intravenously. Tissues were harvested at different times, and the level of antibody deposition was determined by measuring radioactivity. Whole-body small-animal PET of mice receiving (86)Y-labeled antibodies was performed at 6 time points and colocalized with simultaneous micro-CT imaging. RESULTS: The biodistributions of (111)In and (86)Y antibodies were quite similar. The blood, tumor, kidney, and liver tissues contained varying levels of radioactivity. The antibody accumulation in the tumor correlated with molecular size. The IgG steadily increased with time to 24.1 percentage injected dose per gram (%ID/g) at 48 h. The miniantibody accumulated at a similar rate to reach a lower level (14.2 %ID/g) at 48 h but with a higher tumor-to-blood ratio than the IgG. Tumor accumulation of the diabody peaked at 3 h, reaching a much lower level (3.7 %ID/g). A combination of rapid clearance and lower relative affinity of the scFv precluded deposition in the tumor. Small-animal PET results correlated well with the biodistribution results, with similar tumor localization patterns. CONCLUSION: The larger antibody formats (IgG and miniantibody) gave higher tumor uptake levels than did the smaller formats (diabody and scFv). These larger formats may be more suitable for radioimmunotherapy applications, evidenced by the preclinical efficacy previously shown by a report on the IgG format. The smaller formats were rapidly cleared from circulation, and the diabody, which accumulated in the tumor, may be more suitable for radiodiagnostic applications.
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Anticuerpos Monoclonales/farmacocinética , Neoplasias de la Próstata/metabolismo , Radiofármacos/farmacocinética , Animales , Anticuerpos Monoclonales/química , Línea Celular Tumoral , Quelantes/química , Humanos , Radioisótopos de Indio , Isotiocianatos/química , Masculino , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Ácido Pentético/análogos & derivados , Ácido Pentético/química , Tomografía de Emisión de Positrones , Radiofármacos/química , Distribución Tisular , Tomografía Computarizada por Rayos X , Trasplante Heterólogo , Radioisótopos de ItrioRESUMEN
In this Letter we report the synthesis and evaluation of a series of non-amidine inhibitors of Urokinase Plasminogen Activator (uPA). Starting from compound 1, a significant change provided compounds in which the amidine, binding in the S1 pocket, was replaced with a primary amine. Further modifications led to the identification of potent, selective, and orally bioavailable uPA inhibitors.
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Bencilaminas/química , Inhibidores de Serina Proteinasa/química , Activador de Plasminógeno de Tipo Uroquinasa/antagonistas & inhibidores , Administración Oral , Amidinas/química , Animales , Sitios de Unión , Cristalografía por Rayos X , Humanos , Ratas , Inhibidores de Serina Proteinasa/administración & dosificación , Inhibidores de Serina Proteinasa/síntesis química , Relación Estructura-Actividad , Activador de Plasminógeno de Tipo Uroquinasa/metabolismoRESUMEN
Microbial biodiversity provides an increasingly important source of medically and industrially useful compounds. We have isolated 14 actinomycete species from a collection of approximately 300 plant stem samples from the upper Amazonian rainforest in Peru. All of the cultured isolates produce substances with inhibitory activity directed at a range of potential fungal and bacterial pathogens. For some organisms, this activity is very broad in spectrum while other organisms show specific activity against a limited number of organisms. Two of these organisms preferentially inhibit bacterial test organisms over eukaryotic organisms. rDNA sequence analysis indicates that these organisms are not equivalent to any other cultured deposits in GenBank. Our results provide evidence of the untapped biodiversity in the form of biologically active microbes present within the tissues of higher plants.
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Actinobacteria/genética , Actinobacteria/aislamiento & purificación , Biodiversidad , Filogenia , Árboles/microbiología , Actinobacteria/clasificación , Actinobacteria/ultraestructura , Antibiosis , ADN Ribosómico/genética , Datos de Secuencia Molecular , Perú , ARN Bacteriano/genética , Análisis de Secuencia de ADN , Clima TropicalRESUMEN
Hepsin is a type II transmembrane serine protease that is expressed in normal liver, and at lower levels in kidney, pancreas, and testis. Several studies have shown that hepsin mRNA is significantly elevated in most prostate tumors, as well as a significant fraction of ovarian and renal cell carcinomas and hepatomas. Although the overexpression of mRNA in these tumors has been extensively documented, there has been conflicting literature on whether hepsin plays a role in tumor cell growth and progression. Early literature implied a role for hepsin in human tumor cell proliferation, whereas recent studies with a transgenic mouse model for prostate cancer support a role for hepsin in tumor progression and metastases. To evaluate this issue further, we have expressed an activatable form of hepsin, and have generated a set of monoclonal antibodies that neutralize enzyme activity. The neutralizing antibodies inhibit hepsin enzymatic activity in biochemical and cell-based assays. Selected neutralizing and nonneutralizing antibodies were used in cell-based assays with tumor cells to evaluate the effect of antibodies on tumor cell growth and invasion. Neutralizing antibodies failed to inhibit the growth of prostate, ovarian, and hepatoma cell lines in culture. However, potent inhibitory effects of the antibodies were seen on invasion of ovarian and prostate cells in transwell-based invasion assays. These results support a role for hepsin in tumor cell progression but not in primary tumor growth. Consistent with this, immunohistochemical experiments with a mouse monoclonal antibody reveal progressively increased staining of prostate tumors with advanced disease, and in particular, extensive staining of bone metastatic lesions.