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1.
Eur J Med Chem ; 272: 116459, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38704942

RESUMEN

Activation of the aminopeptidase (AP) activity of leukotriene A4 hydrolase (LTA4H) presents a potential therapeutic strategy for resolving chronic inflammation. Previously, ARM1 and derivatives were found to activate the AP activity using the alanine-p-nitroanilide (Ala-pNA) as a reporter group in an enzyme kinetics assay. As an extension of this previous work, novel ARM1 derivatives were synthesized using a palladium-catalyzed Ullmann coupling reaction and screened using the same assay. Analogue 5, an aminopyrazole (AMP) analogue of ARM1, was found to be a potent AP activator with an AC50 of 0.12 µM. An X-ray crystal structure of LTA4H in complex with AMP was refined at 2.7 Å. Despite its AP activity with Ala-pNA substrate, AMP did not affect hydrolysis of the previously proposed natural ligand of LTA4H, Pro-Gly-Pro (PGP). This result highlights a discrepancy between the hydrolysis of more conveniently monitored chromogenic synthetic peptides typically employed in assays and endogenous peptides. The epoxide hydrolase (EH) activity of AMP was measured in vivo and the compound significantly reduced leukotriene B4 (LTB4) levels in a murine bacterial pneumonia model. However, AMP did not enhance survival in the murine pneumonia model over a 14-day period. A liver microsome stability assay showed metabolic stability of AMP. The results suggested that accelerated Ala-pNA cleavage is not sufficient for predicting therapeutic potential, even when the full mechanism of activation is known.


Asunto(s)
Epóxido Hidrolasas , Epóxido Hidrolasas/antagonistas & inhibidores , Epóxido Hidrolasas/metabolismo , Animales , Ratones , Relación Estructura-Actividad , Humanos , Estructura Molecular , Aminopeptidasas/metabolismo , Aminopeptidasas/antagonistas & inhibidores , Éteres/farmacología , Éteres/química , Éteres/síntesis química , Relación Dosis-Respuesta a Droga , Modelos Moleculares , Cristalografía por Rayos X
2.
Mil Med ; 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37963013

RESUMEN

INTRODUCTION: Combat-related wound infections complicate the recovery of wounded military personnel, contributing to overall morbidity and mortality. Wound infections in combat settings present unique challenges because of the size and depth of the wounds, the need to administer emergency care in the field, and the need for subsequent treatment in military facilities. Given the increase in multidrug-resistant pathogens, a novel, broad-spectrum antibiotic is desired across this continuum of care when the standard of care fails. Omadacycline was FDA-approved in 2018 for treatment of adults with acute bacterial skin and skin structure infections (ABSSSI), as well as community-acquired bacterial pneumonia (CABP). It is a broad-spectrum antibiotic with activity against gram-positive, gram-negative, and atypical bacterial pathogens, including multidrug-resistant species. Omadacycline can overcome commonly reported tetracycline resistance mechanisms, ribosomal protection proteins, and efflux pumps, and is available in once-daily intravenous or oral formulations. In this review, we discuss the potential role of omadacycline, which is included in the Department of Defense Formulary, in the context of combat wound infections. MATERIALS AND METHODS: A literature review was undertaken for manuscripts published before July 21, 2023. This included a series of publications found via PubMed and a bibliography made publicly available on the Paratek Pharmaceuticals, Inc. website. Publications presenting primary data published in English on omadacycline in relation to ESKAPEE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Escherichia coli, and Enterobacter species) pathogens and Clostridioides difficile, including in vitro, in vivo, and clinical data were included. RESULTS: Of 260 identified records, 66 were included for evidence review. Omadacycline has in vitro activity against almost all the ESKAPEE pathogens, apart from P. aeruginosa. Importantly, it has activity against the four most prevalent bacterial pathogens that cause wound infections in the military healthcare system: S. aureus, including methicillin-resistant S. aureus, A. baumannii, K. pneumoniae, and E. coli. In vivo studies in rats have shown that omadacycline is rapidly distributed in most tissues, with the highest tissue-to-blood concentration ratios in bone mineral. The clinical efficacy of omadacycline has been assessed in three separate Phase 3 studies in patients with ABSSSI (OASIS-1 and OASIS-2) and with CABP (OPTIC). Overall, omadacycline has an established safety profile in the treatment of both ABSSSI and CABP. CONCLUSIONS: Omadacycline has broad-spectrum activity, the option to be orally administered and an established safety profile, making it a potentially attractive replacement for moxifloxacin in the military individual first aid kit, especially when accounting for the increasing resistance to fluoroquinolones. Further studies and clinical evaluation are warranted to support broader use of omadacycline to treat combat wound infections in the military healthcare system.

3.
Sci Rep ; 12(1): 9443, 2022 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-35676292

RESUMEN

The aminopeptidase activity (AP) of the leukotriene A4 hydrolase (LTA4H) enzyme has emerged as a therapeutic target to modulate host immunity. Initial reports focused on the benefits of augmenting the LTA4H AP activity and clearing its putative pro-inflammatory substrate Pro-Gly-Pro (PGP). However, recent reports have introduced substantial complexity disconnecting the LTA4H modulator 4-methoxydiphenylmethane (4MDM) from PGP as follows: (1) 4MDM inhibits PGP hydrolysis and subsequently inhibition of LTA4H AP activity, and (2) 4MDM activates the same enzyme target in the presence of alternative substrates. Differential modulation of LTA4H by 4MDM was probed in a murine model of acute lung inflammation, which showed that 4MDM modulates the host neutrophilic response independent of clearing PGP. X-ray crystallography showed that 4MDM and PGP bind at the zinc binding pocket and no allosteric binding was observed. We then determined that 4MDM modulation is not dependent on the allosteric binding of the ligand, but on the N-terminal side chain of the peptide. In conclusion, our study revealed that a peptidase therapeutic target can interact with its substrate and ligand in complex biochemical mechanisms. This raises an important consideration when ligands are designed to explain some of the unpredictable outcomes observed in therapeutic discovery targeting LTA4H.


Asunto(s)
Epóxido Hidrolasas , Neumonía , Animales , Modelos Animales de Enfermedad , Ligandos , Ratones
4.
ACS Infect Dis ; 7(11): 2987-2998, 2021 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-34672535

RESUMEN

The ESKAPE pathogens comprise a group of multidrug-resistant bacteria that are the leading cause of nosocomial infections worldwide. The prevalence of antibiotic resistant strains and the relative ease by which bacteria acquire resistance genes highlight the continual need for the development of novel antibiotics against new drug targets. The methylerythritol phosphate (MEP) pathway is an attractive target for the development of new antibiotics. The MEP pathway governs the synthesis of isoprenoids, which are key lipid precursors for vital cell components such as ubiquinone and bacterial hopanoids. Additionally, the MEP pathway is entirely distinct from the corresponding mammalian pathway, the mevalonic acid (MVA) pathway, making the first committed enzyme of the MEP pathway, 1-deoxy-d-xylulose 5-phosphate reductoisomerase (IspC), an attractive target for antibiotic development. To facilitate drug development against two of the ESKAPE pathogens, Acinetobacter baumannii and Klebsiella pneumoniae, we cloned, expressed, purified, and characterized IspC from these two Gram-negative bacteria. Enzyme inhibition assays using IspC from these two pathogens, and compounds fosmidomycin and FR900098, indicate IC50 values ranging from 19.5-45.5 nM. Antimicrobial susceptibility tests with these inhibitors reveal that A. baumannii is susceptible to FR900098, whereas K. pneumoniae is susceptible to both compounds. Finally, to facilitate structure-based drug design of inhibitors targeting A. baumannii IspC, we determined the 2.5 Å crystal structure of IspC from A. baumannii in complex with inhibitor FR900098, and cofactors NADPH and magnesium.


Asunto(s)
Acinetobacter baumannii , Isomerasas Aldosa-Cetosa , Preparaciones Farmacéuticas , Acinetobacter baumannii/genética , Isomerasas Aldosa-Cetosa/genética , Klebsiella pneumoniae/genética
5.
Drugs Today (Barc) ; 57(10): 591-605, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34713868

RESUMEN

Since its initial approval in 2015, daratumumab has had a tremendous impact on the treatment of multiple myeloma. It is a monoclonal antibody that targets CD38, an antigen with high surface expression on multiple myeloma cells. While it initially received approval as a monotherapy for multiply relapsed multiple myeloma, its favorable toxicity profile allowed for combinations with other novel myeloma therapies leading to numerous indications as a component of triplet and quadruplet regimens. These indications now span relapsed/refractory populations and both transplant-eligible and transplant-ineligible patients with newly diagnosed myeloma. Further investigations are underway to continue to expand the reach of daratumumab, including large phase III collaborative trials to assess the efficacy of daratumumab as part of post-transplant maintenance and its impact on smoldering myeloma. The recent introduction of a subcutaneous formulation of daratumumab with proven noninferiority will improve the convenience and accessibility of the drug. In this review, we examine the preclinical development of daratumumab, its pharmacology and clinical investigations that demonstrated its safety and efficacy. Furthermore, we discuss the outstanding questions related to daratumumab and ongoing clinical trials seeking to answer them.


Asunto(s)
Antineoplásicos Inmunológicos , Mieloma Múltiple , Anticuerpos Monoclonales , Protocolos de Quimioterapia Combinada Antineoplásica , Humanos , Mieloma Múltiple/tratamiento farmacológico
6.
Opt Express ; 28(17): 24599-24613, 2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32906999

RESUMEN

We present space and time resolved measurements of the air hydrodynamics induced by femtosecond laser pulse excitation of the air gap between two electrodes at high potential difference. We explore both plasma-based and plasma-free gap excitation. The former uses the plasma left in the wake of femtosecond filamentation, while the latter exploits air heating by multiple-pulse resonant excitation of quantum molecular wavepackets. We find that the cumulative electrode-driven air density depression channel plays the dominant role in the gap evolution leading to breakdown. Femtosecond laser heating serves mainly to initiate the depression channel; the presence of filament plasma only augments the early heating.

7.
ACS Omega ; 5(10): 5170-5175, 2020 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-32201804

RESUMEN

Fosmidomycin inhibits IspC (1-deoxy-d-xylulose 5-phosphate reductoisomerase), the first committed enzyme in the methylerythritol phosphate (MEP) pathway of isoprenoid biosynthesis. The MEP pathway of isoprenoid biosynthesis is essential to the causative agent of the plague, Yersinia pestis, and is entirely distinct from the corresponding mammalian pathway. To further drug development, we established structure-activity relationships of fosmidomycin analogues by assessing a suite of 17 α-phenyl-substituted reverse derivatives of fosmidomycin against Y. pestis IspC. Several of these compounds showed increased potency over fosmidomycin with IC50 values in the nanomolar range. Additionally, we performed antimicrobial susceptibility testing with Y. pestis A1122 (YpA1122). The bacteria were susceptible to several compounds with minimal inhibitory concentration (MIC) values ranging from 128 to 512 µg/mL; a correlation between the IC50 and MIC values was observed.

8.
J Trauma Acute Care Surg ; 88(1): 106-112, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31490336

RESUMEN

BACKGROUND: Unaddressed alcohol use among injured patients may result in recurrent injury or death. Many trauma centers incorporate alcohol screening, brief intervention, and referral to treatment for injured patients with alcohol use disorders, but systematic reviews evaluating the impact of these interventions are lacking. METHODS: An evidence-based systematic review was performed to answer the following population, intervention, comparator, outcomes question: Among adult patients presenting for acute injury, should emergency department, trauma center, or hospital-based alcohol screening with brief intervention and/or referral to treatment be instituted compared with usual care to prevent or decrease reinjury, hospital readmission, alcohol-related offenses, and/or alcohol consumption? A librarian-initiated query of PubMed, MEDLINE, and the Cochrane Library was performed. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the quality of the evidence and create recommendations. The study was registered with PROSPERO (registration number CRD42019122333). RESULTS: Eleven studies met criteria for inclusion, with a total of 1,897 patients who underwent hospital-based alcohol screening, brief intervention, and/or referral to treatment for appropriate patients. There was a relative paucity of data, and studies varied considerably in terms of design, interventions, and outcomes of interest. Overall evidence was assessed as low quality, but a large effect size of intervention was present. CONCLUSION: In adult trauma patients, we conditionally recommend emergency department, trauma center, or hospital-based alcohol screening with brief intervention and referral to treatment for appropriate patients in order to reduce alcohol-related reinjury. LEVEL OF EVIDENCE: Systematic review, Level III.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Tamizaje Masivo/organización & administración , Prevención Secundaria/organización & administración , Centros Traumatológicos/organización & administración , Heridas y Lesiones/cirugía , Adulto , Consumo de Bebidas Alcohólicas/terapia , Servicio de Urgencia en Hospital/organización & administración , Servicio de Urgencia en Hospital/normas , Servicio de Urgencia en Hospital/estadística & datos numéricos , Medicina Basada en la Evidencia/organización & administración , Medicina Basada en la Evidencia/normas , Medicina Basada en la Evidencia/estadística & datos numéricos , Cirugía General/normas , Humanos , Incidencia , Tamizaje Masivo/normas , Tamizaje Masivo/estadística & datos numéricos , Readmisión del Paciente/estadística & datos numéricos , Guías de Práctica Clínica como Asunto , Derivación y Consulta/organización & administración , Derivación y Consulta/normas , Derivación y Consulta/estadística & datos numéricos , Prevención Secundaria/normas , Prevención Secundaria/estadística & datos numéricos , Sociedades Médicas/normas , Centros Traumatológicos/normas , Centros Traumatológicos/estadística & datos numéricos , Estados Unidos , Heridas y Lesiones/epidemiología , Heridas y Lesiones/etiología
9.
J Med Chem ; 62(23): 10605-10616, 2019 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-31751136

RESUMEN

Activation of the leukotriene A4 hydrolase (LTA4H) aminopeptidase (AP) activity with 4-methoxydiphenylmethane (4MDM) promoted resolution of neutrophil infiltration in a murine cigarette smoke-induced model for emphysematous chronic obstructive pulmonary disease. Recently, 4-(4-benzylphenyl)thiazol-2-amine (ARM1) was published as a ligand for LTA4H with potential anti-inflammatory properties. To investigate the effect of modifier structure on enzyme kinetics of LTA4H, a series of analogues bearing structural features of ARM1 and 4MDM were synthesized using trifluoroborate Suzuki coupling reactions. Following, the 2.8 Å X-ray crystal structure of LTA4H complexed with 4-OMe-ARM1, a 4MDM-ARM1 hybrid molecule, was determined. Kinetic analysis showed that ARM1 and related analogues lowered affinity for the enzyme-substrate complex, resulting in a change of mechanism from hyperbolic mixed predominately catalytic activation (HMx(Sp < Ca)A) as observed for 4MDM to a predominately specific activation (HMx(Sp > Ca)A) mechanism. 4-OMe-ARM1 was then shown to dose responsively reduce LTB4 production in human neutrophils.


Asunto(s)
Aminopeptidasas/metabolismo , Antiinflamatorios/farmacología , Activación Enzimática/efectos de los fármacos , Epóxido Hidrolasas/metabolismo , Antiinflamatorios/química , Células Cultivadas , Epóxido Hidrolasas/genética , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Mediadores de Inflamación/metabolismo , Leucotrieno B4/genética , Leucotrieno B4/metabolismo , Estructura Molecular , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo
10.
Transfus Med ; 29(6): 389-393, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31663197

RESUMEN

OBJECTIVES: To assess a multimodal physician-to-physician communication initiative that is low in cost and impact to daily workflow to reduce blood product wastage. BACKGROUND: Blood product stewardship is an important issue in all hospital systems. Previous studies have proposed low-cost interventions to reduce blood product wastage, but few have evaluated improvements in communication between the blood bank and providers. We undertook a prospective quality improvement project focusing on improving communication to reduce blood product wastage. METHODS: We conducted a prospective quality improvement project over the first quarter of 2017, identifying patients with issued but unused blood products. Each service overseeing the care of patients identified on the unit status report was contacted through two possible methods: (i) phone or (ii) proprietary Health Insurance Portability and Accountability Act of 1996 compliant digital messaging application. Collected variables included reserved blood product type and participant time spent. Outcomes included the rate of blood product release and changes in wastage compared with historical data tracked by the blood bank. RESULTS: Eight hundred and forty products were reserved during the study period, of which 436 (52%) were released. Average participant times ranged from 2 ± 1 min to 15 ± 4 min with no significant differences in time spent between participants (P = 0·194). Compared with the average product wastage 10 months prior to project initiation, there were significant reductions in the average wastage for platelets (5·3 ± 2·5 units vs 2·5 ± 1·5 units, P = 0·05), RBCs (6·1 ± 3·7 units vs 0 ± 0 units, P = 0·01) and overall wastage (58·3 ± 14·9 units vs 40 ± 15·7 units, P = 0·05). CONCLUSION: Efforts focusing on improving provider-to-provider communication can reduce blood product wastage.


Asunto(s)
Bancos de Sangre/economía , Eliminación de Residuos Sanitarios/economía , Hospitales , Humanos , Médicos , Estudios Prospectivos , Estudios Retrospectivos
11.
Drugs Today (Barc) ; 55(9): 545-562, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31584572

RESUMEN

On November 21, 2018, the U.S. Food and Drug Administration (FDA) approved glasdegib in combination with low-dose cytarabine (LDAC), for the treatment of newly diagnosed acute myeloid leukemia (AML) in patients > 75 years old or who have comorbidities that would be prohibitive of intensive induction chemotherapy. Glasdegib is a small-molecule inhibitor of a component of the hedgehog (HH) pathway, an upregulated pathway in leukemia and leukemia stem cells that is associated with relapse, drug resistance and poor survival. Preclinical studies suggested that glasdegib could sensitize AML cells to chemotherapy. FDA approval was based on a randomized, placebo-controlled, phase II trial in elderly or infirmed adults with new AML, unable to receive intensive induction chemotherapy, in whom the addition of glasdegib to LDAC nearly doubled the median overall survival compared with LDAC alone. In this report, we examine the preclinical development of glasdegib, its pharmacology and the clinical investigation that demonstrated its safety and efficacy, resulting in its approval. Additionally, we highlight ongoing investigation and future applications of this therapy.


Asunto(s)
Bencimidazoles/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Síndromes Mielodisplásicos/tratamiento farmacológico , Compuestos de Fenilurea/uso terapéutico , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica , Ensayos Clínicos Fase II como Asunto , Citarabina , Aprobación de Drogas , Humanos , Quimioterapia de Inducción , Ensayos Clínicos Controlados Aleatorios como Asunto , Estados Unidos , United States Food and Drug Administration
12.
Eur J Cancer ; 122: 53-60, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31618704

RESUMEN

BACKGROUND: The combination of cisplatin, 5-fluorouracil (5-FU) and cetuximab (PFC) is the reference first-line treatment for recurrent/metastatic (R/M) squamous cell carcinoma of the head and neck (SCCHN). We analysed whether treatment intensification by the addition of docetaxel to PFC improved efficacy in R/M SCCHN. METHODS: A total of 180 patients with R/M SCCHN (1:1) were assigned to receive either cisplatin (40 mg/m2), docetaxel (40 mg/m2) and 5-FU (2000 mg/m2) at days 1 and 8 and cetuximab (400/250 mg/m2) at days 1, 8 and 15 (DPFC) or standard cisplatin (100 mg/m2) at day 1, 5-FU (1000 mg/m2) at days 1-4 and cetuximab (400/250 mg/m2) at days 1, 8 and 15 (PFC). Chemotherapy was repeated every 21 days and continued for a maximum of 6 cycles in absence of disease progression or limiting toxicity, followed by cetuximab maintenance (500 mg/m2 every 2 weeks). The primary end-point was progression-free survival (PFS). RESULTS: A preplanned interim analysis for toxicity after 20 patients/arm revealed excessive grade 3 and 4 gastrointestinal (65%) and infectious toxicities (35%) in arm A, which led to dose reduction of cisplatin to 30 mg/m2 and 5-FU to 1000 mg/m2 for subsequent patients. With a median follow-up of 2 years, grade 4 toxicities were 21.3% vs. 30.8% for DPFC and PFC, respectively. More treatment-related deaths occurred with DPFC vs. PFC, with 11.2% and 6.6%, respectively. For DPFC and PFC, the median PFS was 6.3 vs. 6.4 months (hazard ratio [HR] = 0.97, p = 0.87), the median overall survival was 8.9 vs. 10.6 months (HR = 1.29 p = 0.1) and response rates were 38.2% vs. 31.9% (p = 0.9), respectively. CONCLUSIONS: DPFC failed to improve efficacy in R/M SCCHN. On the contrary, a high toxicity and mortality rate was detected in both arms, which underscores the vulnerability of patients with R/M SCCHN, and research on the need for further optimisation of the front-line chemotherapy backbone is ongoing.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Adulto , Anciano , Cetuximab/administración & dosificación , Cisplatino/administración & dosificación , Supervivencia sin Enfermedad , Docetaxel/administración & dosificación , Esquema de Medicación , Femenino , Fluorouracilo/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
13.
Oper Dent ; 43(3): E129-E151, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29676976

RESUMEN

The literature was reviewed to evaluate the compliance of randomized clinical trials (RCTs) with the CONsolidated Standards of Reporting Trials (CONSORT ) and the risk of bias of these studies through the Cochrane Collaboration risk of bias tool (CCRT). RCTs were searched at Cochrane Library, PubMed, and other electronic databases to find studies about adhesive systems for cervical lesions. The compliance of the articles with CONSORT was evaluated using the following scale: 0 = no description, 1 = poor description, and 2 = adequate description. Descriptive analyses about the number of studies by journal, follow-up period, country, and quality assessments were performed with CCRT for assessing risk of bias in RCTs. One hundred thirty-eight RCTs were left for assessment. More than 30% of the studies received scores of 0 or 1. Flow chart, effect size, allocation concealment, and sample size were more critical items, with 80% receiving a score of 0. The overall CONSORT score for the included studies was 15.0 ± 4.8 points, which represents 46.9% of the maximum CONSORT score. A significant difference among countries was observed ( p<0.001), as well as range of year ( p<0.001). Only 4.3% of the studies were judged as at low risk; 36.2% were classified as having unclear risk and 59.4% as having high risk of bias. The adherence of RCTs evaluating adhesive systems to the CONSORT is low with unclear/high risk of bias.


Asunto(s)
Adhesión a Directriz , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Cuello del Diente/cirugía , Enfermedades Dentales/cirugía , Recubrimiento Dental Adhesivo/normas , Cementos Dentales/uso terapéutico , Adhesión a Directriz/estadística & datos numéricos , Humanos , Variaciones Dependientes del Observador , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos
14.
Lett Appl Microbiol ; 66(4): 329-339, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29341217

RESUMEN

Acetoacetate (AAA) was identified as a biofilm inhibitor in a previous study, where the effect of 190 carbon and nitrogen sources on biofilm amounts by Escherichia coli O157:H7 was determined. With this study, we tested the effect of AAA on growth and biofilm amounts of Cronobacter sakazakii, Serratia marcescens and Yersinia enterocolitica. AAA reduced growth and biofilm amounts of the three pathogens, albeit at rather high concentrations of 10 to 35 mg ml-1 . Acetoacetate at a concentration of 5 mg ml-1 reduced Y. enterocolitica mRNA transcripts of the flagellar master regulator operon flhD, the invasion gene inv, and the adhesion gene yadA. Transcription of the regulator of plasmid-encoded virulence genes virF, the plasmid-encoded virulence gene yopQ, and ymoA were largely unaffected by AAA. Importantly, AAA did not cause an increase in transcription of any of the tested virulence genes. As a more cost efficient homologue of AAA, the effect of ethyl acetoacetate (EAA) was tested. EAA reduced growth, biofilm amounts and live bacterial cell counts up to 3 logs. IC50 values ranged from 0·31 mg ml-1 to 5·6 mg ml-1 . In summary, both AAA and EAA inhibit biofilm, but EAA appears to be more effective. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacterial biofilms are communities of bacteria that form on surfaces and are extremely difficult to remove by conventional physical or chemical techniques, antibiotics or the human immune system. Despite advanced technologies, biofilm still contributes to 60 to 80% of human bacterial infections (NIH and CDC) and cause problems in many natural, environmental, bioindustrial or food processing settings. The discovery of novel substances that inhibit biofilm without increasing the virulence of the bacteria opens doors for countless applications where a reduction of biofilm is desired.


Asunto(s)
Acetoacetatos/farmacología , Antibacterianos/farmacología , Biopelículas/crecimiento & desarrollo , Cronobacter sakazakii/crecimiento & desarrollo , Escherichia coli O157/crecimiento & desarrollo , Serratia marcescens/crecimiento & desarrollo , Yersinia enterocolitica/crecimiento & desarrollo , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Bacterianas/genética , Cronobacter sakazakii/aislamiento & purificación , Proteínas de Unión al ADN/genética , Escherichia coli O157/aislamiento & purificación , Expresión Génica/efectos de los fármacos , Humanos , Operón , Plásmidos , Serratia marcescens/aislamiento & purificación , Virulencia/genética , Yersinia enterocolitica/aislamiento & purificación , Yersinia enterocolitica/patogenicidad
15.
Z Rheumatol ; 76(10): 838-847, 2017 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-28986633

RESUMEN

BACKGROUND: The cervical spine is one of the main sites of manifestation in rheumatoid arthritis outside of the extremities. It can have a decisive influence on disease course via the occurrence of mechanical instabilities as well as neurologic symptoms. Both adequate diagnosis and the corresponding surgical treatment represent a challenge for the involved physicians. MATERIALS AND METHODS: This review presents relevant diagnostic strategies and possibilities for surgical intervention which aim to avoid potentially fatal neurologic symptoms. Basic literature and expert opinions are also discussed. RESULTS AND CONCLUSION: Through target-oriented surgical management, as well as tight clinical and radiologic monitoring during conservative and surgical therapy, potentially fatal disease courses can be avoided.


Asunto(s)
Artritis Reumatoide/diagnóstico , Vértebras Cervicales , Espondilitis Anquilosante/diagnóstico , Artritis Reumatoide/cirugía , Articulación Atlantoaxoidea/diagnóstico por imagen , Articulación Atlantoaxoidea/cirugía , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Diagnóstico Diferencial , Humanos , Inestabilidad de la Articulación/diagnóstico , Inestabilidad de la Articulación/cirugía , Imagen por Resonancia Magnética , Examen Neurológico , Platibasia/diagnóstico , Platibasia/cirugía , Compresión de la Médula Espinal/diagnóstico , Compresión de la Médula Espinal/cirugía , Fusión Vertebral , Espondilitis Anquilosante/cirugía , Tomografía Computarizada por Rayos X
16.
Bone Marrow Transplant ; 52(12): 1623-1628, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29035393

RESUMEN

Donor-lymphocyte infusion (DLI) for relapse following haploidentical hematopoietic cell transplantation (haploHCT) with post-transplant cyclophosphamide (PTCy) has been described in recipients of bone marrow grafts, but not recipients of G-CSF mobilized peripheral blood (PB) grafts. We retrospectively identified patients who underwent DLI following PB-haploHCT with PTCy for relapse, or loss of chimerism (LOC). Twelve patients (57%) received DLI for hematologic relapse/persistent disease, seven (33%) for extramedullary relapse and two (10%) for LOC. Sixteen (76%) received chemotherapy prior to DLI, which did not correlate with response. The most common first dose was 1 × 106 CD3+ cells/kg. Two patients developed grade I aGvHD post DLI, one had grade II and two had grade III. One developed mild skin cGvHD 1361 days post DLI. Pre-DLI aGvHD predicted post-DLI aGvHD (P=0.025). Six patients achieved CR after DLI for overt relapse, one achieved full donor chimerism after LOC. Patients with LOC or EM relapse had superior relapse-free survival following DLI (P=0.029). DLI following PB-haploHCT with PTCy is a viable salvage therapy for overt relapse or LOC without a substantial increase in GvHD, and donor lymphocytes may be collected simultaneously with graft collection to facilitate availability in patients at high risk of relapse.


Asunto(s)
Ciclofosfamida/uso terapéutico , Transfusión de Linfocitos , Trasplante de Células Madre de Sangre Periférica/métodos , Terapia Recuperativa/métodos , Anciano , Supervivencia sin Enfermedad , Enfermedad Injerto contra Huésped/etiología , Neoplasias Hematológicas/terapia , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Donantes de Tejidos , Trasplante Haploidéntico , Resultado del Tratamiento
17.
Bioorg Med Chem ; 25(20): 5477-5482, 2017 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-28830719

RESUMEN

The recent emergence of multidrug-resistant Acinetobacter baumannii strains and the non-efficacy of currently available antibiotics against such infections have led to an urgent need for the development of novel antibacterials. In an effort to address this problem, we have identified three novel inhibitors, namely, D5, D12 and D6 using in silico screening with a homology model of the outer membrane protein W2 (OmpW2) from A. baumannii, as the proposed new drug target. OmpW is an eight-stranded ß-barrel protein involved in the transport of hydrophobic molecules across the outer membrane and maintenance of homeostasis under cellular stress. The antimicrobial activities of compounds D5, D12 and D6 were evaluated against a panel of clinical isolates of A. baumannii strains. These compounds inhibited the growth of the strains with minimum inhibitory concentration (MIC) ranges of 1-32µg/mL. Time-kill kinetic studies with the highly virulent and multidrug-resistant strain, A. baumannii 5075, indicated that D6 exhibited the highest bactericidal activity asa≥3log10 CFU/mL (99.9%) reduction in colony count from the initial inoculum was observed after 30min incubation. D5 and D12 reduced at least 1log10 CFU/mL (90%) of the initial inoculum after 24h. In conclusion, these three lead inhibitors have provided two distinct chemical scaffolds for further analog design and optimizations, using chemical synthesis, to develop more potent inhibitors of the pathogen.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/farmacología , Descubrimiento de Drogas , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Acinetobacter baumannii/crecimiento & desarrollo , Antibacterianos/síntesis química , Antibacterianos/química , Relación Dosis-Respuesta a Droga , Cinética , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Estructura Molecular , Relación Estructura-Actividad , Factores de Tiempo
18.
Oncogene ; 36(40): 5648-5657, 2017 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-28581523

RESUMEN

Although single base-pair resolution DNA methylation landscapes for embryonic and different somatic cell types provided important insights into epigenetic dynamics and cell-type specificity, such comprehensive profiling is incomplete across human cancer types. This prompted us to perform genome-wide DNA methylation profiling of 22 samples derived from normal tissues and associated neoplasms, including primary tumors and cancer cell lines. Unlike their invariant normal counterparts, cancer samples exhibited highly variable CpG methylation levels in a large proportion of the genome, involving progressive changes during tumor evolution. The whole-genome sequencing results from selected samples were replicated in a large cohort of 1112 primary tumors of various cancer types using genome-scale DNA methylation analysis. Specifically, we determined DNA hypermethylation of promoters and enhancers regulating tumor-suppressor genes, with potential cancer-driving effects. DNA hypermethylation events showed evidence of positive selection, mutual exclusivity and tissue specificity, suggesting their active participation in neoplastic transformation. Our data highlight the extensive changes in DNA methylation that occur in cancer onset, progression and dissemination.


Asunto(s)
Metilación de ADN , ADN de Neoplasias/metabolismo , Neoplasias/genética , Animales , Emparejamiento Base , Elementos de Facilitación Genéticos , Genoma Humano , Humanos , Regiones Promotoras Genéticas
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