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1.
Cell ; 184(1): 194-206.e14, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33357447

RESUMO

Wnts are evolutionarily conserved ligands that signal at short range to regulate morphogenesis, cell fate, and stem cell renewal. The first and essential steps in Wnt secretion are their O-palmitoleation and subsequent loading onto the dedicated transporter Wntless/evenness interrupted (WLS/Evi). We report the 3.2 Å resolution cryogenic electron microscopy (cryo-EM) structure of palmitoleated human WNT8A in complex with WLS. This is accompanied by biochemical experiments to probe the physiological implications of the observed association. The WLS membrane domain has close structural homology to G protein-coupled receptors (GPCRs). A Wnt hairpin inserts into a conserved hydrophobic cavity in the GPCR-like domain, and the palmitoleate protrudes between two helices into the bilayer. A conformational switch of highly conserved residues on a separate Wnt hairpin might contribute to its transfer to receiving cells. This work provides molecular-level insights into a central mechanism in animal body plan development and stem cell biology.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Proteínas Wnt/metabolismo , Sequência de Aminoácidos , Animais , Dissulfetos/metabolismo , Glicosilação , Humanos , Interações Hidrofóbicas e Hidrofílicas , Peptídeos e Proteínas de Sinalização Intracelular/isolamento & purificação , Modelos Moleculares , Ligação Proteica , Domínios Proteicos , Estrutura Secundária de Proteína , Transporte Proteico , Receptores Acoplados a Proteínas G/isolamento & purificação , Receptores Acoplados a Proteínas G/ultraestrutura , Homologia Estrutural de Proteína , Relação Estrutura-Atividade , Proteínas Wnt/química , Proteínas Wnt/isolamento & purificação , Proteínas Wnt/ultraestrutura
2.
Am J Kidney Dis ; 83(4): 531-545, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38108672

RESUMO

Ultrasonography is increasingly being performed by clinicians at the point of care, and nephrologists are no exception. This Core Curriculum illustrates how ultrasonography can be incorporated into clinical decision making across the spectrum of kidney disease to optimize the care nephrologists provide to patients. Sonography is valuable in outpatient and inpatient settings for the diagnosis and management of acute and chronic kidney disease, evaluation of cystic disease, urinary obstruction, pain, hematuria, proteinuria, assessment of volume status, and in providing guidance for kidney biopsy. As kidney disease advances, ultrasound is useful in the placement and maintenance of temporary and permanent access for dialysis. After kidney transplantation, ultrasonography is critical for evaluation of allograft dysfunction and for biopsies. Sonography skills expedite patient care and enhance the practice of nephrology and are relatively easily acquired with training. It is our hope that this curriculum will encourage nephrologists to learn and apply this valuable skill.


Assuntos
Nefrologia , Insuficiência Renal Crônica , Humanos , Nefrologia/educação , Ultrassonografia , Diálise Renal , Currículo , Insuficiência Renal Crônica/diagnóstico por imagem , Insuficiência Renal Crônica/terapia
3.
Catheter Cardiovasc Interv ; 103(5): 771-781, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38451155

RESUMO

BACKGROUND: ProGlide is a percutaneous suture-mediated closure device used in arterial and venous closure following percutaneous intervention. Risk of vascular complications from use, particularly related to failure in hemostasis, or acute vessel closure, remains significant and often related to improper suture deployment. We describe a technique of ultrasound-guided ProGlide deployment in transfemoral transcatheter aortic valve implantation (TF-TAVI). AIMS: The aim of this study is to assess vascular outcomes for ultrasound-guided deployment of ProGlide vascular closure devices in patients undergoing TF-TAVI. METHODS: We collected relevant clinical data of patients undergoing TAVI in a large volume centre. PRIMARY OUTCOME: main access Valve Academic Research Consortium 3 (VARC-3) major vascular complication. SECONDARY OUTCOME: any major/minor VARC-3 vascular complication, its type (bleed or ischemia), and treatment required (medical, percutaneous, or surgical). We performed inverse weighting propensity score analysis to compare the population undergoing ultrasound-guided versus conventional ProGlide deployment for main TAVI access. Ultrasound technique for ProGlide insertion was performed as described below. RESULTS: Five hundred and seventeen patients undergoing TF-TAVI were included. PRIMARY OUTCOME: In 126 (ultrasound-guided) and 391 (conventional ProGlide insertion), 0% versus 1.8% (p < 0.001) had a major VARC-3 vascular complication, respectively. SECONDARY OUTCOME: 0.8% (one minor VARC-3 bleed) vs 4.1% (13 bleeds and three occlusions) had any VARC-3 vascular complication (major and minor) (p < 0.001). Surgical treatment of vascular complication was required in 0.8% versus 1.3% (p = NS). CONCLUSIONS: Ultrasound-guided deployment of ProGlide for vascular closure reduced the risk of major vascular complications in a large population undergoing TAVI.


Assuntos
Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Dispositivos de Oclusão Vascular , Humanos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Estudos de Coortes , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Resultado do Tratamento , Hemorragia/etiologia , Comportamento de Redução do Risco , Ultrassonografia de Intervenção/efeitos adversos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia
4.
Environ Microbiol ; 24(12): 5984-5997, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36251278

RESUMO

Coalbed deposits are a unique subsurface environment and represent an underutilized resource for methane generation. Microbial communities extant in coalbed deposits are responsible for key subsurface biogeochemical cycling and could be utilized to enhance methane production in areas where existing gas wells have depleted methane stores, or in coalbeds that are unmined, or conversely be utilized for mitigation of methane release. Here we utilize metagenomics and metagenome-assembled genomes (MAGs) to identify extant microbial lineages and genome-resolved microbial metabolisms of coalbed produced water, which has not yet been explored in the Appalachian Basin (AppB). Our analyses resulted in the recovery of over 40 MAGs from 8 coalbed methane wells. The most commonly identified taxa among samples were hydrogenotrophic methanogens from the order Methanomicrobiales and these dominant MAGs were highly similar to one another. Conversely, low-abundance coalbed bacterial populations were taxonomically and functionally diverse, mostly belonging to a variety of Proteobacteria classes, and encoding various hydrocarbon solubilization and degradation pathways. The data presented herein provides novel insights into AppB coalbed microbial ecology, and our findings provide new perspectives on underrepresented Methanocalculus species and low-relative abundance bacterial assemblages in coalbed environments, and their potential roles in stimulation or mitigation of methane release.


Assuntos
Metagenômica , Methanomicrobiales , Methanomicrobiales/metabolismo , Metagenoma , Hidrocarbonetos/metabolismo , Metano/metabolismo , Bactérias
5.
Am J Kidney Dis ; 77(2): 204-215.e1, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32961245

RESUMO

RATIONALE & OBJECTIVE: Outcomes of patients hospitalized with coronavirus disease 2019 (COVID-19) and acute kidney injury (AKI) are not well understood. The goal of this study was to investigate the survival and kidney outcomes of these patients. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Patients (aged≥18 years) hospitalized with COVID-19 at 13 hospitals in metropolitan New York between March 1, 2020, and April 27, 2020, followed up until hospital discharge. EXPOSURE: AKI. OUTCOMES: Primary outcome: in-hospital death. SECONDARY OUTCOMES: requiring dialysis at discharge, recovery of kidney function. ANALYTICAL APPROACH: Univariable and multivariable time-to-event analysis and logistic regression. RESULTS: Among 9,657 patients admitted with COVID-19, the AKI incidence rate was 38.4/1,000 patient-days. Incidence rates of in-hospital death among patients without AKI, with AKI not requiring dialysis (AKI stages 1-3), and with AKI receiving dialysis (AKI 3D) were 10.8, 31.1, and 37.5/1,000 patient-days, respectively. Taking those without AKI as the reference group, we observed greater risks for in-hospital death for patients with AKI 1-3 and AKI 3D (HRs of 5.6 [95% CI, 5.0-6.3] and 11.3 [95% CI, 9.6-13.1], respectively). After adjusting for demographics, comorbid conditions, and illness severity, the risk for death remained higher among those with AKI 1-3 (adjusted HR, 3.4 [95% CI, 3.0-3.9]) and AKI 3D (adjusted HR, 6.4 [95% CI, 5.5-7.6]) compared with those without AKI. Among patients with AKI 1-3 who survived, 74.1% achieved kidney recovery by the time of discharge. Among those with AKI 3D who survived, 30.6% remained on dialysis at discharge, and prehospitalization chronic kidney disease was the only independent risk factor associated with needing dialysis at discharge (adjusted OR, 9.3 [95% CI, 2.3-37.8]). LIMITATIONS: Observational retrospective study, limited to the NY metropolitan area during the peak of the COVID-19 pandemic. CONCLUSIONS: AKI in hospitalized patients with COVID-19 was associated with significant risk for death.


Assuntos
Injúria Renal Aguda , COVID-19 , Mortalidade Hospitalar , Hospitalização/estatística & dados numéricos , Diálise Renal , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/fisiopatologia , Injúria Renal Aguda/terapia , COVID-19/diagnóstico , COVID-19/mortalidade , COVID-19/fisiopatologia , COVID-19/terapia , Feminino , Humanos , Incidência , Testes de Função Renal/métodos , Testes de Função Renal/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , New York/epidemiologia , Avaliação de Processos e Resultados em Cuidados de Saúde , Diálise Renal/métodos , Diálise Renal/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2/isolamento & purificação , Análise de Sobrevida
6.
Inorg Chem ; 60(16): 11852-11865, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34311548

RESUMO

A 2,2'-bipyridine with bulky triphenylamine substituents in the 6 and 6' positions of the ligand (6,6'-ditriphenylamine-2,2'-bipyridine, 6,6'-diTPAbpy) was generated. Despite the steric bulk, the ligand readily formed bis(homoleptic) complexes with copper(I) and silver(I) ions. Unfortunately, efforts to use the 6,6'-diTPAbpy system to generate heteroleptic [Cu(6,6'-diTPAbpy)(bpy)]+ complexes were unsuccessful with only the [Cu(6,6'-diTPAbpy)2](PF6) complex observed. The 6,6'-diTPAbpy ligand could also be reacted with 6-coordinate metal ions that featured small ancillary ligands, namely, the [Re(CO)3Cl] and [Ru(CO)2Cl2] fragments. While the complexes could be formed in good yields, the steric bulk of the TPA units does alter the coordination geometry. This is most readily seen in the [(6,6'-diTPAbpy)Re(CO)3Cl] complex where the Re(I) ion is forced to sit 23° out of the plane formed by the bpy unit. The electrochemical and photophysical properties of the family of compounds were also examined. 6,6'-diTPAbpy exhibits a strong ILCT absorption band (356 nm, 50 mM-1 cm-1) which displays a small increase in intensity for the homoleptic complexes ([Cu(6,6'-diTPAbpy)2]+; 353 nm, 72 mM-1 cm-1, [Ag(6,6'-diTPAbpy)2]+; 353 nm, 75 mM-1 cm-1), despite containing 2 equiv of the ligand, attributed to an increased dihedral angle between the TPA and bpy moieties. For the 6-coordinate complexes the ILCT band is further decreased in intensity and overlaps with MLCT bands, consistent with a further increased TPA-bpy dihedral angle. Emission from the 1ILCT state is observed at 436 nm (τ = 4.4 ns) for 6,6'-diTPAbpy and does not shift for the Cu, Ag, and Re complexes, although an additional 3MLCT emission is observed for [Re(6,6'-diTPAbpy)(CO)3Cl] (640 nm, τ = 13.8 ns). No emission was observed for [Ru(6,6'-diTPAbpy)(CO)2Cl2]. Transient absorption measurements revealed the population of a 3ILCT state for the Cu and Ag complexes (τ = 80 ns). All assignments were supported by TD-DFT calculations and resonance Raman spectroscopic measurements.

7.
Kidney Int ; 98(1): 209-218, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32416116

RESUMO

The rate of acute kidney injury (AKI) associated with patients hospitalized with Covid-19, and associated outcomes are not well understood. This study describes the presentation, risk factors and outcomes of AKI in patients hospitalized with Covid-19. We reviewed the health records for all patients hospitalized with Covid-19 between March 1, and April 5, 2020, at 13 academic and community hospitals in metropolitan New York. Patients younger than 18 years of age, with end stage kidney disease or with a kidney transplant were excluded. AKI was defined according to KDIGO criteria. Of 5,449 patients admitted with Covid-19, AKI developed in 1,993 (36.6%). The peak stages of AKI were stage 1 in 46.5%, stage 2 in 22.4% and stage 3 in 31.1%. Of these, 14.3% required renal replacement therapy (RRT). AKI was primarily seen in Covid-19 patients with respiratory failure, with 89.7% of patients on mechanical ventilation developing AKI compared to 21.7% of non-ventilated patients. 276/285 (96.8%) of patients requiring RRT were on ventilators. Of patients who required ventilation and developed AKI, 52.2% had the onset of AKI within 24 hours of intubation. Risk factors for AKI included older age, diabetes mellitus, cardiovascular disease, black race, hypertension and need for ventilation and vasopressor medications. Among patients with AKI, 694 died (35%), 519 (26%) were discharged and 780 (39%) were still hospitalized. AKI occurs frequently among patients with Covid-19 disease. It occurs early and in temporal association with respiratory failure and is associated with a poor prognosis.


Assuntos
Injúria Renal Aguda/virologia , Infecções por Coronavirus/complicações , Pneumonia Viral/complicações , Insuficiência Respiratória/complicações , Injúria Renal Aguda/epidemiologia , Idoso , COVID-19 , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Pacientes Internados/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Insuficiência Respiratória/virologia , Estudos Retrospectivos
8.
Inorg Chem ; 59(3): 1785-1803, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31934759

RESUMO

Fundamental insights into the mechanism of triplet-excited-state interligand energy transfer dynamics and the origin of dual emission for phosphorescent iridium(III) complexes are presented. The complexes [Ir(C∧N)2(N∧N)]+ (HC∧N = 2-phenylpyridine (1a-c), 2-(2,4-difluorophenyl)pyridine (2a-c), 1-benzyl-4-phenyl-1,2,3-triazole (3a-c); N∧N = 1-benzyl-4-(pyrid-2-yl)-1,2,3-triazole (pytz, a), 1-benzyl-4-(pyrimidin-2-yl)-1,2,3-triazole (pymtz, b), 1-benzyl-4-(pyrazin-2-yl)-1,2,3-triazole (pyztz, c)) are phosphorescent in room-temperature fluid solutions from triplet metal-to-ligand charge transfer (3MLCT) states admixed with either ligand-centered (3LC) (1a, 2a, and 2b) or ligand-to-ligand charge transfer (3LL'CT) character (1c, 2c, and 3a-c). Particularly striking is the observation that pyrimidine-based complex 1b exhibits dual emission from both 3MLCT/3LC and 3MLCT/3LL'CT states. At 77 K, the 3MLCT/3LL'CT component is lost from the photoluminescence spectra of 1b, with emission exclusively arising from its 3MLCT/3LC state, while for 2c switching from 3MLCT/3LL'CT- to 3MLCT/3LC-based emission is observed. Femtosecond transient absorption data reveal distinct spectral signatures characteristic of the population of 3MLCT/3LC states for 1a, 2a, and 2b which persist throughout the 3 ns time frame of the experiment. These 3MLCT/3LC state signatures are apparent in the transient absorption spectra for 1c and 2c immediately following photoexcitation but rapidly evolve to yield spectral profiles characteristic of their 3MLCT/3LL'CT states. Transient data for 1b reveals intermediate behavior: the spectral features of the initially populated 3MLCT/3LC state also undergo rapid evolution, although to a lesser extent than that observed for 1c and 2c, behavior assigned to the equilibration of the 3MLCT/3LC and 3MLCT/3LL'CT states. Density functional theory (DFT) calculations enabled minima to be optimized for both 3MLCT/3LC and 3MLCT/3LL'CT states of 1a-c and 2a-c. Indeed, two distinct 3MLCT/3LC minima were optimized for 1a, 1b, 2a, and 2b distinguished by upon which of the two C∧N ligands the excited electron resides. The 3MLCT/3LC and 3MLCT/3LL'CT states for 1b are very close in energy, in excellent agreement with experimental data demonstrating dual emission. Calculated vibrationally resolved emission spectra (VRES) for the complexes are in excellent agreement with experimental data, with the overlay of spectral maxima arising from emission from the 3MLCT/3LC and 3MLCT/3LL'CT states of 1b convincingly reproducing the observed experimental spectral features. Analysis of the optimized excited-state geometries enable the key structural differences between the 3MLCT/3LC and 3MLCT/3LL'CT states of the complexes to be identified and quantified. The calculation of interconversion pathways between triplet excited states provides for the first time a through-space mechanism for a photoinduced interligand energy transfer process. Furthermore, examination of structural changes between the possible emitting triplet excited states reveals the key bond vibrations that mediate energy transfer between these states. This work therefore provides for the first time detailed mechanistic insights into the fundamental photophysical processes of this important class of complexes.

10.
Appl Environ Microbiol ; 83(8)2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28159795

RESUMO

Microbial activity in the produced water from hydraulically fractured oil and gas wells may potentially interfere with hydrocarbon production and cause damage to the well and surface infrastructure via corrosion, sulfide release, and fouling. In this study, we surveyed the microbial abundance and community structure of produced water sampled from 42 Marcellus Shale wells in southwestern Pennsylvania (well age ranged from 150 to 1,846 days) to better understand the microbial diversity of produced water. We sequenced the V4 region of the 16S rRNA gene to assess taxonomy and utilized quantitative PCR (qPCR) to evaluate the microbial abundance across all 42 produced water samples. Bacteria of the order Halanaerobiales were found to be the most abundant organisms in the majority of the produced water samples, emphasizing their previously suggested role in hydraulic fracturing-related microbial activity. Statistical analyses identified correlations between well age and biocide formulation and the microbial community, in particular, the relative abundance of Halanaerobiales We further investigated the role of members of the order Halanaerobiales in produced water by reconstructing and annotating a Halanaerobium draft genome (named MDAL1), using shotgun metagenomic sequencing and metagenomic binning. The recovered draft genome was found to be closely related to the species H. congolense, an oil field isolate, and Halanaerobium sp. strain T82-1, also recovered from hydraulic fracturing produced water. Reconstruction of metabolic pathways revealed Halanaerobium sp. strain MDAL1 to have the potential for acid production, thiosulfate reduction, and biofilm formation, suggesting it to have the ability to contribute to corrosion, souring, and biofouling events in the hydraulic fracturing infrastructure.IMPORTANCE There are an estimated 15,000 unconventional gas wells in the Marcellus Shale region, each generating up to 8,000 liters of hypersaline produced water per day throughout its lifetime (K. Gregory, R. Vidic, and D. Dzombak, Elements 7:181-186, 2011, https://doi.org/10.2113/gselements.7.3.181; J. Arthur, B. Bohm, and M. Layne, Gulf Coast Assoc Geol Soc Trans 59:49-59, 2009; https://www.marcellusgas.org/index.php). Microbial activity in produced waters could lead to issues with corrosion, fouling, and souring, potentially interfering with hydraulic fracturing operations. Previous studies have found microorganisms contributing to corrosion, fouling, and souring to be abundant across produced water samples from hydraulically fractured wells; however, these findings were based on a limited number of samples and well sites. In this study, we investigated the microbial community structure in produced water samples from 42 unconventional Marcellus Shale wells, confirming the dominance of the genus Halanaerobium in produced water and its metabolic potential for acid and sulfide production and biofilm formation.


Assuntos
Firmicutes/metabolismo , Consórcios Microbianos , Campos de Petróleo e Gás/microbiologia , Águas Residuárias/microbiologia , Incrustação Biológica , Firmicutes/genética , Firmicutes/isolamento & purificação , Genoma Bacteriano , Sequenciamento de Nucleotídeos em Larga Escala , Redes e Vias Metabólicas , Metagenoma , Pennsylvania , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real
11.
Dis Esophagus ; 30(2): 1-5, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27629426

RESUMO

The diagnosis of achalasia is generally made based on patient symptoms, the appearance of the esophagus on endoscopy and barium esophagogram, and esophageal manometry. In addition, timed barium esophagography (TBE) can give useful information on the clearance of liquid barium over a 10 minute period and the passage of a barium tablet. What is unclear is how well these physiological measurements of esophageal function correlate with patient-perceived health-related quality of life. Our aim was to assess whether objective physiological measurements of high-resolution manometry (HRM) and TBE will correlate with quantitative achalasia-related health-related quality of life (HRQoL) measurements. Patients referred for possible surgical treatment of achalasia were assessed preoperatively in the following manner. A gastroenterologist and surgeon clinically evaluated all patients. In addition to history and physical examination, patients underwent further testing with TBE, upper gastrointestinal endoscopy, and HRM. The diagnosis of achalasia was based on HRM. Prior to surgical treatment, patients completed the 'Measure of Achalasia Disease Severity' (ADS) which is a validated instrument assessing the severity of achalasia-associated HRQoL. Hundred and twenty patients were included in this study. The mean ADS score was 24.9 ± 3.6. There was no statistically significant difference in score among the achalasia types: I, 24.0 ± 4.3; II, 25.4 ± 3.2; III, 24.3 ± 4.6. Using linear regression analysis, there was no statistically significant correlation between ADS scores and TBE column height or width at 1 and 5 minutes. There was no statistically significant difference between patients who could pass a 13 mm barium tablet (26.4 ± 3.4) and those who could not (24.9 ± 3.6). There was no statistically significant correlation between LES pressure and IRP with ADS scores. There is poor correlation between patient-perceived health-related quality of life and objective physiological measurements of achalasia. Therefore, the assessment of treatment outcomes of achalasia will need to require both an assessment of esophageal physiology as well as HRQoL.


Assuntos
Acalasia Esofágica/diagnóstico , Esôfago/fisiopatologia , Qualidade de Vida , Índice de Gravidade de Doença , Avaliação de Sintomas/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sulfato de Bário , Meios de Contraste , Autoavaliação Diagnóstica , Acalasia Esofágica/fisiopatologia , Acalasia Esofágica/psicologia , Esofagoscopia/métodos , Esôfago/diagnóstico por imagem , Feminino , Humanos , Modelos Lineares , Masculino , Manometria/métodos , Pessoa de Meia-Idade , Radiografia/métodos , Reprodutibilidade dos Testes , Adulto Jovem
12.
Molecules ; 22(10)2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-29048381

RESUMO

A new "click" ligand, 2,6-bis(1-(pyridin-4-ylmethyl)-1H-1,2,3-triazol-4-yl)pyridine (L) featuring a tridentate 2,6-bis(1,2,3-triazol-4-yl)pyridine (tripy) pocket and two pyridyl (py) units was synthesized in modest yield (42%) using the copper(I) catalyzed azide-alkyne cycloaddition (CuAAC) reaction. The coordination chemistry of the ligand with silver(I) and iron(II) ions was examined using a battery of solution (¹H and DOSY (diffusion ordered spectroscopy) nuclear magnetic resonance (NMR), infrared and absorption spectroscopies, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS)), and solid state (X-ray crystallography, elemental analysis) techniques. When treated with silver(I) ions, the ligand forms discrete [Ag(L)]⁺ (X-, where X- = BF4-, NO3- or SbF6-) complexes in dimethyl sulfoxide (DMSO) solution but these complexes crystallize as coordination polymers. The addition of [Fe(H2O)6](BF4)2 to an acetonitrile solution of the ligand forms the expected monomeric octahedral [Fe(L)2]2+ complex and treatment of the iron(II) complex with AgBF4 generates a heterometallic linear coordination polymer.


Assuntos
Compostos Ferrosos/química , Piridinas/química , Compostos de Prata/química , Química Click , Cristalografia por Raios X , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular
13.
Am J Kidney Dis ; 68(2): 187-192, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27113506

RESUMO

Procedures are a key component to the practice of nephrology. The Accreditation Council for Graduate Medical Education (ACGME) requires nephrology fellows to acquire skills and demonstrate competency in the performance of several procedures during fellowship training, including temporary hemodialysis catheter placement, biopsy of native and transplanted kidneys, and various dialytic therapies. It is also required that fellows acquire competency in the interpretation of renal imaging, including renal ultrasound, during their training. To gain a more recent perspective of nephrology fellows' experiences regarding renal ultrasonography, dialysis catheter placement, and kidney biopsies, we carried out a national survey of nephrology fellows in May 2014. A majority of the programs did not offer formal clinical training in renal ultrasonography. In addition, a significant percentage of fellows in adult nephrology may not be acquiring the required procedural skills and competency during fellowship training. In this perspective, we explore some of the reasons for this occurrence and propose some measures that the nephrology training community can take to enhance procedural skills and competency of fellows.


Assuntos
Cateterismo , Cateteres de Demora , Competência Clínica , Bolsas de Estudo , Rim/diagnóstico por imagem , Rim/patologia , Nefrologia/educação , Diálise Renal , Ultrassonografia , Biópsia , Humanos , Diálise Renal/instrumentação , Estados Unidos
14.
Angew Chem Int Ed Engl ; 55(36): 10697-701, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27485699

RESUMO

Whilst [Os(N^N)3 ](2+) complexes are supposed to be photochemically inert to ligand loss, the complex [Os(btz)3 ](2+) (btz=1,1'-dibenzyl-4,4'-bi-1,2,3-triazolyl) undergoes unprecedented photolytic reactivity to liberate free btz (Φ363 ≈1.2 %). Further, both cis and trans isomers of the photodechelated ligand-loss solvento intermediate [Os(κ(2) -btz)2 (κ(1) -btz)(NCMe)](2+) are unambiguously observed and characterized by NMR spectroscopy and mass spectrometry.

16.
J Transl Med ; 12: 177, 2014 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-24950711

RESUMO

BACKGROUND: Toll-like receptor 4 (TLR4), a lipopolysaccharide (LPS) receptor complex signal-transducing molecule, plays a crucial role in sensing LPS from gram-negative bacteria. TLR4 signaling pathway activation by LPS plays a major role in sepsis pathogenesis. A single nucleotide polymorphism, rs11536889, in the 3'-untranslated region of the TLR4 gene is thought to affect TLR4 translation. This study aimed to investigate whether organ failure in sepsis patients is related to the TLR4 rs11536889 genotype. METHODS: Adult Caucasian patients with sepsis from the intensive care unit of a university medical center were followed up for 90 days, and organ failure was recorded as the primary outcome variable. Blood samples were collected at enrollment for TLR4 rs11536889 genotyping. Sepsis-related organ failure assessment (SOFA) scores were quantified at sepsis onset and throughout the observational period to monitor organ failure. RESULTS: A total of 210 critically ill patients with sepsis were enrolled into this study. Wild-type GG was compared to GC/CC. During their stay in the intensive care unit, GG patients presented significantly higher SOFA scores than did C allele carriers (7.9 ± 4.5 and 6.8 ± 4.2, respectively; p = 0.0005). Analysis of organ-specific SOFA sub-scores revealed significant differences in three organ systems: renal, coagulation and hepatic (p = 0.0005, p = 0.0245 and p < 0.0001, respectively). Additionally, the rs11536889 polymorphism was associated with a higher incidence of gram-negative infections. CONCLUSIONS: These results offer the first evidence that TLR4 rs11536889 is a useful marker of organ failure in patients with sepsis.


Assuntos
Biomarcadores/sangue , Transtornos da Coagulação Sanguínea/genética , Falência Hepática/genética , Polimorfismo Genético , Insuficiência Renal/genética , Sepse/genética , Receptor 4 Toll-Like/genética , Idoso , Transtornos da Coagulação Sanguínea/complicações , Feminino , Humanos , Falência Hepática/complicações , Masculino , Pessoa de Meia-Idade , Insuficiência Renal/complicações , Sepse/complicações
18.
Inflamm Res ; 63(2): 149-60, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24240228

RESUMO

OBJECTIVE AND DESIGN: TNF-α neutralization is associated with increased mortality in mouse cecal ligation puncture (CLP) models. AZD9773 is an ovine polyclonal human TNF-α immune Fab, with pharmacological properties that differ from previously studied anti-TNF-α agents. We explored the safety and efficacy of therapeutically administered AZD9773 in mouse CLP sepsis. METHODS: A moderate/severe-grade CLP model resulting in 20-30 % 5-day survival and a mild-grade CLP model resulting in ~70 % 5-day survival were established in human TNF-α transgene/murine TNF null (Tg1278/-/-) mice. TREATMENT: Mice received saline resuscitation and imipenem administration every 12 h (0-72 h post-CLP). AZD9773 (or DigiFab control) was dosed 24, 36, 48 and 60 h post-CLP. RESULTS: Therapeutic dosing of AZD9773 in moderate/severe-grade CLP resulted in significantly increased survival (>70 %) compared with DigiFab (27 %, P < 0.05). Therapeutic dosing of AZD9773 in mild-grade CLP did not significantly affect survival outcome compared with DigiFab or imipenem alone (~60-70 % survival). CONCLUSIONS: These data demonstrate that TNF-α neutralization can improve survival in moderate/severe CLP sepsis. TNF-α suppression in mild-grade models was not associated with survival benefit and did not increase 5-day mortality. These findings suggest that therapeutic benefit following TNF-α attenuation in models of sepsis may depend on model severity.


Assuntos
Fragmentos Fab das Imunoglobulinas/uso terapêutico , Sepse/tratamento farmacológico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Ceco/lesões , Ceco/cirurgia , Citocinas/sangue , Fragmentos Fab das Imunoglobulinas/sangue , Fragmentos Fab das Imunoglobulinas/farmacologia , Ligadura , Lipopolissacarídeos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Camundongos Transgênicos , Sepse/sangue , Sepse/imunologia , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
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