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mRNA-4157 (V940) is an individualized neoantigen therapy (INT) targeting up to 34 patient-specific tumor neoantigens to induce T cell responses and potentiate anti-tumor activity. We report mechanistic insights into the immunogenicity of mRNA-4157 via characterization of T cell responses to neoantigens from the first-in-human phase 1, KEYNOTE-603 study (NCT03313778) in patients with resected non-small cell lung cancer (Part A: 1mg mRNA-4157, n = 4) or resected cutaneous melanoma (Part D: 1mg mRNA-4157 + 200mg pembrolizumab, n = 12). Safety, tolerability, and immunogenicity were assessed. All patients experienced ≥1 treatment-emergent adverse event (AE); there were no grade 4/5 AEs or dose-limiting toxicities. mRNA-4157 alone induced consistent de novo, and strengthened pre-existing, T cell responses to targeted neoantigens. Following combination therapy, sustained mRNA-4157-induced neoantigen-specific T cell responses and expansion of cytotoxic CD8 and CD4 T cells were observed. These findings show the potential of a novel mRNA INT approach in oncology.
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BACKGROUND: Checkpoint inhibitors are standard adjuvant treatment for stage IIB-IV resected melanoma, but many patients recur. Our study aimed to evaluate whether mRNA-4157 (V940), a novel mRNA-based individualised neoantigen therapy, combined with pembrolizumab, improved recurrence-free survival and distant metastasis-free survival versus pembrolizumab monotherapy in resected high-risk melanoma. METHODS: We did an open-label, randomised, phase 2b, adjuvant study of mRNA-4157 plus pembrolizumab versus pembrolizumab monotherapy in patients, enrolled from sites in the USA and Australia, with completely resected high-risk cutaneous melanoma. Patients with completely resected melanoma (stage IIIB-IV) were assigned 2:1 to receive open-label mRNA-4157 plus pembrolizumab or pembrolizumab monotherapy. mRNA-4157 was administered intramuscularly (maximum nine doses) and pembrolizumab intravenously (maximum 18 doses) in 3-week cycles. The primary endpoint was recurrence-free survival in the intention-to-treat population. This ongoing trial is registered at ClinicalTrials.gov, NCT03897881. FINDINGS: From July 18, 2019, to Sept 30, 2021, 157 patients were assigned to mRNA-4157 plus pembrolizumab combination therapy (n=107) or pembrolizumab monotherapy (n=50); median follow-up was 23 months and 24 months, respectively. Recurrence-free survival was longer with combination versus monotherapy (hazard ratio [HR] for recurrence or death, 0·561 [95% CI 0·309-1·017]; two-sided p=0·053), with lower recurrence or death event rate (24 [22%] of 107 vs 20 [40%] of 50); 18-month recurrence-free survival was 79% (95% CI 69·0-85·6) versus 62% (46·9-74·3). Most treatment-related adverse events were grade 1-2. Grade ≥3 treatment-related adverse events occurred in 25% of patients in the combination group and 18% of patients in the monotherapy group, with no mRNA-4157-related grade 4-5 events. Immune-mediated adverse event frequency was similar for the combination (37 [36%]) and monotherapy (18 [36%]) groups. INTERPRETATION: Adjuvant mRNA-4157 plus pembrolizumab prolonged recurrence-free survival versus pembrolizumab monotherapy in patients with resected high-risk melanoma and showed a manageable safety profile. These results provide evidence that an mRNA-based individualised neoantigen therapy might be beneficial in the adjuvant setting. FUNDING: Moderna in collaboration with Merck Sharp & Dohme, a subsidiary of Merck & Co, Rahway, NJ, USA.
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Melanoma , Neoplasias Cutáneas , Humanos , Adyuvantes Inmunológicos/uso terapéutico , Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/cirugía , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/cirugíaRESUMEN
PURPOSE: Talazoparib is an inhibitor of the poly (ADP-ribose) polymerase (PARP) family of enzymes and is FDA-approved for patients with (suspected) deleterious germline BRCA1/2-mutated, HER2negative, locally advanced or metastatic breast cancer. Because knowledge of the pharmacodynamic (PD) effects of talazoparib in patients has been limited to studies of PARP enzymatic activity (PARylation) in peripheral blood mononuclear cells, we developed a study to assess tumoral PD response to talazoparib treatment (NCT01989546). METHODS: We administered single-agent talazoparib (1 mg/day) orally in 28-day cycles to adult patients with advanced solid tumors harboring (suspected) deleterious BRCA1 or BRCA2 mutations. The primary objective was to examine the PD effects of talazoparib; the secondary objective was to determine overall response rate (ORR). Tumor biopsies were mandatory at baseline and post-treatment on day 8 (optional at disease progression). Biopsies were analyzed for PARylation, DNA damage response (γH2AX), and epithelialâmesenchymal transition. RESULTS: Nine patients enrolled in this trial. Four of six patients (67%) evaluable for the primary PD endpoint exhibited a nuclear γH2AX response on day 8 of treatment, and five of six (83%) also exhibited strong suppression of PARylation. A transition towards a more mesenchymal phenotype was seen in 4 of 6 carcinoma patients, but this biological change did not affect γH2AX or PAR responses. The ORR was 55% with the five partial responses lasting a median of six cycles. CONCLUSION: Intra-tumoral DNA damage response and inhibition of PARP enzymatic activity were confirmed in patients with advanced solid tumors harboring BRCA1/2 mutations after 8 days of talazoparib treatment.
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Antineoplásicos , Neoplasias de la Mama , Adulto , Femenino , Humanos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Leucocitos Mononucleares , Ftalazinas , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Poli(ADP-Ribosa) Polimerasas/genéticaRESUMEN
PURPOSE: Soft-tissue sarcomas (STS) are a rare, heterogeneous group of mesenchymal tumors. For decades the mainstay of treatment for advanced, unresectable STS has been palliative chemotherapy. High levels of activated MET receptor have been reported in various sarcoma cell lines, together with elevated vascular endothelial growth factor (VEGF) levels in patients with STS, suggesting that dual targeting of the VEGF and MET pathways with the multi-receptor tyrosine kinase inhibitor cabozantinib would result in clinical benefit in this population. PATIENTS AND METHODS: We performed an open-label, multi-institution, single-arm phase II trial of single-agent cabozantinib in adult patients with advanced STS and progressive disease after at least 1 standard line of systemic therapy. Patients received 60 mg oral cabozantinib once daily in 28-day cycles, and dual primary endpoints of overall response rate and 6-month progression-free survival (PFS) were assessed. Changes in several circulating biomarkers were assessed as secondary endpoints. RESULTS: Six (11.1%; 95% CI, 4.2%-22.6%) of the 54 evaluable patients enrolled experienced objective responses (all partial responses). Six-month PFS was 49.3% (95% CI, 36.2%-67.3%), with a median time on study of 4 cycles (range, 1-99). The most common grade 3/4 adverse events were hypertension (7.4%) and neutropenia (16.7%). Patients' levels of circulating hepatocyte growth factor (HGF), soluble MET, and VEGF-A generally increased after a cycle of therapy, while soluble VEGFR2 levels decreased, regardless of clinical outcome. CONCLUSIONS: Cabozantinib single-agent antitumor activity was observed in patients with selected STS histologic subtypes (alveolar soft-part sarcoma, undifferentiated pleomorphic sarcoma, extraskeletal myxoid chondrosarcoma, and leiomyosarcoma) highlighting the biomolecular diversity of STS.
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Sarcoma , Factor A de Crecimiento Endotelial Vascular , Anilidas/administración & dosificación , Humanos , Inhibidores de Proteínas Quinasas/uso terapéutico , Piridinas , Sarcoma/tratamiento farmacológico , Sarcoma/patologíaRESUMEN
PURPOSE: To evaluate the tissue distribution and clinical significance of OX40 and OX40L in human non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Using multiplexed quantitative immunofluorescence, we conducted simultaneous and localized measurements of OX40 and OX40L proteins, major T-cell subsets, and conventional type 1 dendritic cells (cDC1) in 614 primary NSCLCs from three independent cohorts represented in tissue microarrays. We also measured OX40L protein in samples from a phase I clinical trial of intratumor administration of a lipid nanoparticle encapsulated mRNA encoding OX40L (mRNA-2416) in human solid tumors. Finally, we studied the OX40 pathway in 212 uterine/ovarian serous carcinomas. RESULTS: OX40 protein was expressed in approximately 90% of NSCLCs, and OX40L was detected in approximately 10% of cases. Increased expression of OX40 was associated with higher CD4+ and CD8+ T lymphocytes, as well as cDC1s. Elevated expression of OX40L was consistently associated with increased CD4+ tumor-infiltrating lymphocytes and longer overall survival. No association was found between OX40 or OX40L levels and oncogenic driver mutations in EGFR and KRAS in lung adenocarcinomas. Delivering OX40L mRNA using intratumor mRNA-2416 injection mediated increased local OX40L protein levels that was most prominent in a patient with ovarian serous carcinoma. Detectable OX40L protein levels were observed in 15% of primary uterine/ovarian serous malignancies and associated with longer survival. CONCLUSIONS: The OX40 pathway is expressed in a fraction of NSCLCs and is associated with a favorable immune contexture. Although OX40L is uncommonly expressed in NSCLC and serous malignancies, it is associated with better prognosis and can be introduced using exogenous mRNA.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/genética , Humanos , Liposomas , Neoplasias Pulmonares/genética , Nanopartículas , Ligando OX40/genéticaRESUMEN
BACKGROUND: Percutaneous reduction with fixation and open reduction internal fixation are often used to treat intra-articular calcaneus fractures with no consensus on the preferred method. Open techniques have been associated with an increased risk of wound complications, while percutaneous techniques may result in inferior reduction capabilities. These injuries pose a challenge to patients as they often result in poor patient outcomes. We retrospectively analyzed patient outcomes of a single surgeon's experience in treating these injuries at a busy urban Level 1 trauma center. METHODS: Patients with intra-articular calcaneus fractures managed operatively over 10 years with a minimum six-month follow-up were included. Patients were divided into two cohorts based on operative technique: closed reduction and percutaneous fixation (CRPF) or open reduction internal fixation (ORIF). Descriptive analysis of each cohort included postoperative infection, the need for repeat operations, development of post-traumatic subtalar arthritis, and reduction capabilities as assessed by Bohler's angle. RESULTS: Sixty-two patients were included in this study, with 33 patients in the CRPF group and 29 patients in the ORIF group. Infection requiring a return to the operating room occurred in 1 (3%) CRPF and 7 (24%) ORIF patients. Instrumentation was removed in 23 (70%) CRPF and 9 (31%) ORIF patients. Clinical subtalar arthritis developed in 10 (30%) CRPF and 7 (24%) ORIF patients, requiring arthrodesis in 2 (6%) and 5 (17%) patients, respectively. Both techniques had acceptable restoration of Bohler's angle immediately postoperatively and at final follow-up. CONCLUSIONS: Percutaneous reduction with fixation and open reduction internal fixation may both be considered for the surgical treatment of intra-articular calcaneal fractures. Indications for each technique may vary between surgeons, and each has its own set of risk factors and complications, however, both have been shown to result in an acceptable reduction. LEVEL OF EVIDENCE: Level IV.
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BACKGROUND: TRC102 inhibits base excision repair by binding abasic sites and preventing AP endonuclease processing; it potentiates the activity of alkylating agents, including temozolomide, in murine models. In published xenograft studies, TRC102 enhanced the antitumor effect of temozolomide regardless of cell line genetic characteristics, e.g., O6-methylguanine DNA methyltransferase (MGMT), mismatch repair (MMR), or p53 status. MATERIALS AND METHODS: We conducted a phase 1 trial of TRC102 with temozolomide given orally on days 1-5 of 28-day cycles in adult patients with refractory solid tumors that had progressed on standard therapy. Tumor induction of nuclear biomarkers of DNA damage response (DDR) γH2AX, pNBs1, and Rad51 was assessed in the context of MGMT and MMR protein expression for expansion cohort patients. RESULTS: Fifty-two patients were enrolled (37 escalation, 15 expansion) with 51 evaluable for response. The recommended phase 2 dose was 125 mg TRC102, 150 mg/m2 temozolomide QDx5. Common adverse events (grade 3/4) included anemia (19%), lymphopenia (12%), and neutropenia (10%). Four patients achieved partial responses (1 non-small cell lung cancer, 2 granulosa cell ovarian cancer, and 1 colon cancer) and 13 patients had a best response of stable disease. Retrospective analysis of 15 expansion cohort patients did not demonstrate a correlation between low tumor MGMT expression and patient response, but treatment induced nuclear Rad51 responses in 6 of 12 patients. CONCLUSIONS: The combination of TRC 102 with temozolomide is active, with 4 of 51 patients experiencing a partial response and 13 of 51 experiencing stable disease, and the side effect profile is manageable.
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LESSONS LEARNED: The combination of the antiangiogenic agent ziv-aflibercept and the heat shock protein 90 inhibitor ganetespib was associated with several serious and unexpected adverse events and was not tolerable on the dosing schedule tested.Studies such as these emphasize the importance of considering overlapping toxicities when designing novel treatment combination regimens. BACKGROUND: Although inhibition of angiogenesis is an effective strategy for cancer treatment, acquired resistance to antiangiogenic therapy is common. Heat shock protein 90 (Hsp90) is a molecular chaperone that regulates various oncogenic signaling pathways involved in acquired resistance and has been shown to play a role in angiogenesis. Combining an antiangiogenic agent with an Hsp90 inhibitor has therefore been proposed as a strategy for preventing resistance and improving antitumor activity. We conducted a single-arm phase I study evaluating the combination of ziv-aflibercept, an antiangiogenic drug, with the Hsp90 inhibitor ganetespib. METHODS: Adult patients were eligible if they had recurrent or metastatic gastrointestinal carcinomas, nonsquamous non-small cell lung carcinomas, urothelial carcinomas, or sarcomas that had progressed after at least one line of standard therapy. Ziv-aflibercept was administered intravenously on days 1 and 15, and ganetespib was administered intravenously on days 1, 8, and 15, of each 28-day cycle. RESULTS: Five patients were treated with the combination. Although three patients achieved stable disease, study treatment was associated with several serious and unexpected adverse events. CONCLUSION: The dose escalation phase of this study was not completed, but the limited data obtained suggest that this combination may be too toxic when administered on this dosing schedule.
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Neoplasias/tratamiento farmacológico , Receptores de Factores de Crecimiento Endotelial Vascular/uso terapéutico , Proteínas Recombinantes de Fusión/uso terapéutico , Sarcoma/tratamiento farmacológico , Triazoles/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Femenino , Humanos , Masculino , Neoplasias/patología , Proteínas Recombinantes de Fusión/farmacología , Sarcoma/patología , Triazoles/farmacologíaRESUMEN
OBJECTIVES: To prevent leg length discrepancy (LLD) after locked femoral nailing in patients with comminuted femoral shaft fractures. DESIGN: Prospective consecutive case series aimed at quality improvement. SETTING: Level 1 Trauma Center PATIENTS:: Ninety-eight consecutive patients with a comminuted femoral shaft fracture underwent statically locked intramedullary nailing, with a focused attempt at minimizing LLD during surgery. INTERVENTION: A computed tomography scanogram of both legs was performed on postoperative day 1 to assess for residual LLD. Patients were offered the option to have LLD >1.5 cm corrected before discharge. MAIN OUTCOME MEASURE: LLD >1.5 cm. RESULTS: Twenty-one patients (21.4%) were found to have an LLD >1.5 cm. An LLD >1.5 cm occurred in 10/55 (18%) antegrade nail patients and 11/43 (26%) retrograde nail patients (P = 0.27). No difference was noted based on the mechanism of injury, surgeon training and OTA/AO type B versus C injury. Ninety of 98 patients left with <1.5 cm LLD, 13/21 had a correction all to ≤0.6 cm, and 8 decided to accept the LLD and declined early correction. CONCLUSIONS: No patient left the hospital with an LLD >1.5 cm after locked intramedullary nailing for a comminuted femoral shaft fracture without being informed and the option of early correction. We recommend using a full-length computed tomography scanogram after IM nailing of comminuted femur fractures to prevent iatrogenic LLD. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
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Fracturas del Fémur/cirugía , Fijación Intramedular de Fracturas/efectos adversos , Fracturas Conminutas/cirugía , Diferencia de Longitud de las Piernas/diagnóstico por imagen , Mejoramiento de la Calidad , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Clavos Ortopédicos , Femenino , Fracturas del Fémur/diagnóstico por imagen , Fémur/diagnóstico por imagen , Fémur/cirugía , Fijación Intramedular de Fracturas/métodos , Fracturas Conminutas/diagnóstico por imagen , Humanos , Diferencia de Longitud de las Piernas/etiología , Diferencia de Longitud de las Piernas/prevención & control , Diferencia de Longitud de las Piernas/cirugía , Masculino , Persona de Mediana Edad , Reoperación , Adulto JovenRESUMEN
Purpose Desmoid tumors (aggressive fibromatosis) arise from connective tissue cells or fibroblasts. In general, they are slow growing and do not metastasize; however, locally aggressive desmoid tumors can cause severe morbidity and loss of function. Disease recurrence after surgery and/or radiation and diagnosis of multifocal desmoid tumors highlight the need to develop effective systemic treatments for this disease. In this study, we evaluate objective response rate after therapy with the γ-secretase inhibitor PF-03084014 in patients with recurrent, refractory, progressive desmoid tumors. Patients and Methods Seventeen patients with desmoid tumors received PF-03084014 150 mg orally twice a day in 3-week cycles. Response to treatment was evaluated at cycle 1 and every six cycles, that is, 18 weeks, by RECIST (Response Evaluation Criteria in Solid Tumors) version 1.1. Patient-reported outcomes were measured at baseline and at every restaging visit by using the MD Anderson Symptoms Inventory. Archival tumor and blood samples were genotyped for somatic and germline mutations in APC and CTNNB1. Results Of 17 patients accrued to the study, 15 had mutations in APC or CTNNB1 genes. Sixteen patients (94%) were evaluable for response; five (29%) experienced a confirmed partial response and have been on study for more than 2 years. Another five patients with prolonged stable disease as their best response remain on study. Patient-reported outcomes confirmed clinician reporting that the investigational agent was well tolerated and, in subgroup analyses, participants who demonstrated partial response also experienced clinically meaningful and statistically significant improvements in symptom burden. Conclusion PF-03084014 was well tolerated and demonstrated promising clinical benefit in patients with refractory, progressive desmoid tumors who receive long-term treatment.
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Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Antineoplásicos/uso terapéutico , Fibromatosis Agresiva/tratamiento farmacológico , Tetrahidronaftalenos/uso terapéutico , Valina/análogos & derivados , Proteína de la Poliposis Adenomatosa del Colon/genética , Adulto , Anciano , Antineoplásicos/efectos adversos , Femenino , Fibromatosis Agresiva/diagnóstico por imagen , Fibromatosis Agresiva/genética , Genotipo , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Mutación , Medición de Resultados Informados por el Paciente , Criterios de Evaluación de Respuesta en Tumores Sólidos , Retratamiento , Evaluación de Síntomas , Tetrahidronaftalenos/efectos adversos , Tomografía Computarizada por Rayos X , Valina/efectos adversos , Valina/uso terapéutico , Adulto Joven , beta Catenina/genéticaRESUMEN
The repair of DNA damage is a critical cellular process governed by multiple biochemical pathways that are often found to be defective in cancer cells. The poly(ADP-ribose) polymerase (PARP) family of proteins controls response to single-strand DNA breaks by detecting these damaged sites and recruiting the proper factors for repair. Blocking this pathway forces cells to utilize complementary mechanisms to repair DNA damage. While PARP inhibition may not, in itself, be sufficient to cause tumor cell death, inhibition of DNA repair with PARP inhibitors is an effective cytotoxic strategy when it is used in patients who carry other defective DNA-repair mechanisms, such as mutations in the genes BRCA 1 and 2. This discovery has supported the development of PARP inhibitors (PARPi), agents that have proven effective against various types of tumors that carry BRCA mutations. With the application of next-generation sequencing of tumors, there is increased interest in looking beyond BRCA mutations to identify genetic and epigenetic aberrations that might lead to similar defects in DNA repair, conferring susceptibility to PARP inhibition. Identification of these genetic lesions and the development of screening assays for their detection may allow for the selection of patients most likely to respond to this class of anticancer agents. This article provides an overview of clinical trial results obtained with PARPi and describes the companion diagnostic assays being established for patient selection. In addition, we review known mechanisms for resistance to PARPi and potential strategies for combining these agents with other types of therapy.
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Antineoplásicos/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Antineoplásicos/farmacología , Femenino , Humanos , Neoplasias Ováricas/enzimología , Neoplasias Ováricas/patología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Poli(ADP-Ribosa) Polimerasas/metabolismoRESUMEN
Poly(ADP-ribose) polymerase (PARP), which was first described over 50 years ago by Mandel, are a family of protein enzymes involved in DNA damage response and works by recognizing the single-strand DNA break (ssDNA) and then effecting DNA repair. A double-strand DNA (dsDNA) break can be repaired by one of two different pathways: homologous recombination (HR) or non-homologous end joining (NHEJ). Homologous recombination occurs in the G2 or M phase of the cell cycle when a sister chromatid is available to use as a template for repair. Because a template is available, HR is a high fidelity, error-free form of DNA repair. With NHEJ there is not a template and the DNA is trimmed and ligated which is a very error-prone process of repair which can lead to genetic instability. Exploiting these mechanism led to development of PARP inhibitors with the idea of utilizing synthetic lethality, where two deficiencies each having no effect on the cellular outcome become lethal when combined, as single agent in BRCA deficient patients or as chemotherapy/radiotherapy combinations to inhibit ssDNA repair. The recent approval of olaparib in BRCA deficient ovarian cancer patients in US and Europe has opened up a whole new treatment option for ovarian cancer patients. This review will discuss the different PARP inhibitors in development and the potential use of this class of agents in the future.
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The ability of bacteria to sense environmental cues and adapt is essential for their survival. The use of second-messenger signaling molecules to translate these cues into a physiological response is a common mechanism employed by bacteria. The second messenger 3'-5'-cyclic diadenosine monophosphate (c-di-AMP) has been linked to a diverse set of biological processes involved in maintaining cell viability and homeostasis, as well as pathogenicity. A complex network of both protein and RNA receptors inside the cell activates specific pathways and mediates phenotypic outputs in response to c-di-AMP. Structural analysis of these RNA and protein receptors has revealed the different recognition elements employed by these effectors to bind the same small molecule. Herein, using a series of c-di-AMP analogues, we probed the interactions made with a riboswitch and a phosphodiesterase protein to identify the features important for c-di-AMP binding and recognition. We found that the ydaO riboswitch binds c-di-AMP in two discrete sites with near identical affinity and a Hill coefficient of 1.6. The ydaO riboswitch distinguishes between c-di-AMP and structurally related second messengers by discriminating against an amine at the C2 position more than a carbonyl at the C6 position. We also identified phosphate-modified analogues that bind both the ydaO RNA and GdpP protein with high affinity, whereas symmetrically modified ribose analogues exhibited a substantial decrease in ydaO affinity but retained high affinity for GdpP. These ligand modifications resulted in increased resistance to enzyme-catalyzed hydrolysis by the GdpP enzyme. Together, these data suggest that these c-di-AMP analogues could be useful as chemical tools to specifically target subsections of second-messenger signaling pathways.
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Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Fosfatos de Dinucleósidos/química , Fosfatos de Dinucleósidos/metabolismo , ARN Bacteriano/química , ARN Bacteriano/metabolismo , Bacillus subtilis/metabolismo , Cristalografía por Rayos X , Hidrolasas Diéster Fosfóricas/química , Hidrolasas Diéster Fosfóricas/metabolismo , Unión Proteica/fisiología , Estructura Secundaria de Proteína , Ribonucleasas/química , Ribonucleasas/metabolismo , Riboswitch/fisiología , Sistemas de Mensajero Secundario/fisiologíaRESUMEN
An institutional review board-approved retrospective study was performed at a level 1 trauma center to evaluate the adequacy of current treatment guidelines in the management of humerus fractures following civilian gunshot injuries. Fifty-four patients with a humerus shaft fracture from a low-velocity gunshot wound were included in the study. Twenty-nine patients were treated nonoperatively, while 25 patients had operative treatment, with 14 undergoing plate fixation, 6 having application of an external fixator, 3 receiving an intramedullary rod, and 2 having irrigation and debridement with fracture immobilization provided by a brace. Patient demographics and injury data, radiographic analyses, and treatment complications were recorded. Healing of soft tissue and bony injuries, including fracture alignment in patients treated nonoperatively, was also evaluated. Fifty-two of 54 patients had minor soft tissue damage and were treated successfully with minimal local wound care. Two patients with larger wounds required extended wound care with repeated irrigation and debridement. Overall, 47 of 54 fractures healed with the primary mode of treatment, and 7 patients went on to nonunion requiring further intervention. Of the patients treated nonoperatively, the average deformity was 16.5°±7.4° in the coronal plane and 4.4°±4.0° in the sagittal plane. This study supports the view that the majority of humerus fractures following civilian gunshot wounds may be treated nonoperatively, with a select group of patients requiring surgical stabilization.
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Fracturas del Húmero/epidemiología , Fracturas del Húmero/terapia , Sistema de Registros , Fracturas del Hombro/epidemiología , Fracturas del Hombro/terapia , Heridas por Arma de Fuego/epidemiología , Heridas por Arma de Fuego/terapia , Adolescente , Adulto , Curación de Fractura , Humanos , Michigan/epidemiología , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Resultado del Tratamiento , Adulto JovenRESUMEN
The degree to which waters in a given watershed will be affected by nutrient export can be defined as that watershed's nutrient vulnerability. This study applied concepts of specific phosphorus (P) vulnerability to develop intrinsic groundwater vulnerability risk assessments in a 32 km(2) karst watershed (spring zone of contribution) in a relatively intensive agricultural landscape. To explain why emergent spring water was below an ecological impairment threshold, concepts of P attenuation potential were investigated along the nutrient transfer continuum based on soil P buffering, depth to bedrock, and retention within the aquifer. Surface karst features, such as enclosed depressions, were reclassified based on P attenuation potential in soil at the base. New techniques of high temporal resolution monitoring of P loads in the emergent spring made it possible to estimate P transfer pathways and retention within the aquifer and indicated small-medium fissure flows to be the dominant pathway, delivering 52-90% of P loads during storm events. Annual total P delivery to the main emerging spring was 92.7 and 138.4 kg total P (and 52.4 and 91.3 kg as total reactive P) for two monitored years, respectively. A revised groundwater vulnerability assessment was used to produce a specific P vulnerability map that used the soil and hydrogeological P buffering potential of the watershed as key assumptions in moderating P export to the emergent spring. Using this map and soil P data, the definition of critical source areas in karst landscapes was demonstrated.
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Monitoreo del Ambiente/métodos , Fósforo/análisis , Agua Subterránea/análisis , Medición de Riesgo , Movimientos del AguaRESUMEN
BACKGROUND: Reversal of warfarin with plasma accounts for a large amount of fresh-frozen plasma transfused in the United States. The use of vitamin K is an alternate strategy. STUDY DESIGN AND METHODS: Records of vitamin K prescriptions for warfarin reversal were examined and recipients identified where data were available on dosage, route of administration (oral [PO] and intravenous [IV]) and the availability of both pre- and postadministration international normalized ratio(s) (INRs). RESULTS: A total of 135 administration events were evaluated: 81 PO and 54 IV. The median (range) preadministration INRs were 5.8 (1.9-16.5) versus 5.0 (1.4-16.5; p=0.61) and the median (range) for the postadministration INRs were 2.4 (1.0-10.4) and 2.1 (1.2-8.2; p<0.01) for the PO and IV routes, respectively. The median (range) doses were 2.5(1-10) and 2.0(1-10) mg for PO and IV, respectively (p<0.01). A total of 44% of the IV vitamin K group achieved an INR of 2 or less within 12 hours versus 14% for the PO route (p<0.01). In multilinear regression the preadministration INR (r=0.14, p<0.01) and time after administration (r=-0.05, p<0.01) were independent variables influencing the postadministration INR but the dose administered (r=0.09, p=0.07) was not. CONCLUSION: Vitamin K needs to be given IV if urgent partial correction (<12 hr) of warfarin is required. No influence of dose administered in the range 1 to 10 mg on the postadministration INR was observed.
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Vitamina K/administración & dosificación , Warfarina/efectos adversos , Warfarina/antagonistas & inhibidores , Administración Intravenosa , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Anticoagulantes/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pautas de la Práctica en Medicina/tendencias , Estudios Retrospectivos , Vitamina K/efectos adversos , Warfarina/administración & dosificaciónRESUMEN
Conduit and other karstic flows to aquifers, connecting agricultural soils and farming activities, are considered to be the main hydrological mechanisms that transfer phosphorus from the land surface to the groundwater body of a karstified aquifer. In this study, soil source and pathway components of the phosphorus (P) transfer continuum were defined at a high spatial resolution; field-by-field soil P status and mapping of all surface karst features was undertaken in a > 30 km(2) spring contributing zone. Additionally, P delivery and water discharge was monitored in the emergent spring at a sub-hourly basis for over 12 months. Despite moderate to intensive agriculture, varying soil P status with a high proportion of elevated soil P concentrations and a high karstic connectivity potential, background P concentrations in the emergent groundwater were low and indicative of being insufficient to increase the surface water P status of receiving surface waters. However, episodic P transfers via the conduit system increased the P concentrations in the spring during storm events (but not >0.035 mg total reactive P L(-1)) and this process is similar to other catchments where the predominant transfer is via episodic, surface flow pathways; but with high buffering potential over karst due to delayed and attenuated runoff. These data suggest that the current definitions of risk and vulnerability for P delivery to receiving surface waters should be re-evaluated as high source risk need not necessarily result in a water quality impact. Also, inclusion of conduit flows from sparse water quality data in these systems may over-emphasise their influence on the overall status of the groundwater body.
Asunto(s)
Agua Subterránea/química , Fósforo/análisis , Suelo/química , Movimientos del Agua , Contaminantes Químicos del Agua/análisis , Agricultura , Fenómenos Geológicos , Irlanda , Estaciones del AñoRESUMEN
Macrocyclic peptides with multiple disulfide cross-linkages, such as those produced by plants and those found in nonhuman primates, as components of the innate immunity, hold great promise for molecular therapy because of their broad biological activities and high chemical, thermal, and enzymatic stability. However, for some, because of their intricate spatial arrangement and elaborate interstrand cross-linkages, they are difficult to prepare de novo in large quantities and high purity, due to the nonselective nature of disulfide-bond formation. We show that the disulfide bridges of RTD-1, a member of the θ-defensin subfamily, could be replaced with noncovalent Watson-Crick hydrogen bonds without significantly affecting its biological activities. The work provides a general strategy for engineering conformationally rigid, cyclic peptides without the need for disulfide-bond reinforcement.
Asunto(s)
Antibacterianos/farmacología , Ácidos Nucleicos de Péptidos/farmacología , Péptidos Cíclicos/farmacología , Antibacterianos/química , Relación Dosis-Respuesta a Droga , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Ácidos Nucleicos de Péptidos/química , Péptidos Cíclicos/química , Relación Estructura-ActividadRESUMEN
BACKGROUND: Conventional treatment for tibiotalar joint arthritis relies on arthrodesis or prosthetic arthroplasty. Fresh osteochondral allografting is an alternative procedure to replace diseased articular cartilage. METHODS: Eleven patients (average age 43 years; range 18 to 65 years) had fresh osteochondral grafting of the tibiotalar joint. The diagnoses were posttraumatic arthritis in seven ankles, osteoarthritis in two, and an osteochondral defect in two. Precise cuts were made using the Agility (DePuy, Warsaw IN) ankle arthroplasty jigs. Bipolar replacements were used in nine ankles and unipolar in two. Results were evaluated using outcome scores, physical examinations, and standing ankle radiographs. RESULTS: At a minimum followup of 24 (average 33; range 26 to 45) months, six of the 11 ankles had successful grafting procedures. The average AOFAS score preoperatively improved from 55 to 73 postoperatively (p = 0.01). The patients' pain, gait, and walking surface scores were all significantly improved (p < 0.05). Of the five failures three underwent successful repeat allografting and one was revised to a total ankle arthroplasty, and one has had no further surgery. The ankle range of motion arc was 30 degrees or more in six ankles. Additional surgery included five talofibular joint debridements, three repeat graftings, two hardware removals, and one conversion to a prosthetic ankle replacement. There was one intraoperative fibular fracture and one superficial wound infection. The serum of 10 patients tested positive for cytotoxic HLA antibodies postoperatively. Radiographs revealed moderate and severe joint degeneration in six ankles; however, this did not necessarily correlate with a poor outcome. Poor results tended to occur in ankles with a graft-host size mismatch or graft thickness of less than 7 mm. CONCLUSION: Fresh osteochondral transplantation for tibiotalar joint arthritis is a promising alternative to arthrodesis and prosthetic replacement. Early results demonstrate successful outcomes and good pain relief in over half the patients in this series.