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1.
BMC Musculoskelet Disord ; 23(1): 238, 2022 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-35277150

RESUMEN

BACKGROUND: Long-term opioid use, which may have significant individual and societal impacts, has been documented in up to 20% of patients after trauma or orthopaedic surgery. The objectives of this scoping review were to systematically map the research on strategies aiming to prevent chronic opioid use in these populations and to identify knowledge gaps in this area. METHODS: This scoping review is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) Checklist. We searched seven databases and websites of relevant organizations. Selected studies and guidelines were published between January 2008 and September 2021. Preventive strategies were categorized as: system-based, pharmacological, educational, multimodal, and others. We summarized findings using measures of central tendency and frequency along with p-values. We also reported the level of evidence and the strength of recommendations presented in clinical guidelines. RESULTS: A total of 391 studies met the inclusion criteria after initial screening from which 66 studies and 20 guidelines were selected. Studies mainly focused on orthopaedic surgery (62,1%), trauma (30.3%) and spine surgery (7.6%). Among system-based strategies, hospital-based individualized opioid tapering protocols, and regulation initiatives limiting the prescription of opioids were associated with statistically significant decreases in morphine equivalent doses (MEDs) at 1 to 3 months following trauma and orthopaedic surgery. Among pharmacological strategies, only the use of non-steroidal anti-inflammatory drugs and beta blockers led to a significant reduction in MEDs up to 12 months after orthopaedic surgery. Most studies on educational strategies, multimodal strategies and psychological strategies were associated with significant reductions in MEDs beyond 1 month. The majority of recommendations from clinical practice guidelines were of low level of evidence. CONCLUSIONS: This scoping review advances knowledge on existing strategies to prevent long-term opioid use in trauma and orthopaedic surgery patients. We observed that system-based, educational, multimodal and psychological strategies are the most promising. Future research should focus on determining which strategies should be implemented particularly in trauma patients at high risk for long-term use, testing those that can promote a judicious prescription of opioids while preventing an illicit use, and evaluating their effects on relevant patient-reported and social outcomes.


Asunto(s)
Trastornos Relacionados con Opioides , Procedimientos Ortopédicos , Ortopedia , Analgésicos Opioides/uso terapéutico , Lista de Verificación , Humanos , Trastornos Relacionados con Opioides/epidemiología , Trastornos Relacionados con Opioides/prevención & control , Procedimientos Ortopédicos/efectos adversos
2.
Physiology (Bethesda) ; 35(6): 415-429, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-33052775

RESUMEN

The Na+-K+-Cl- cotransporters play key physiological and pathophysiological roles by regulating the membrane potential of many cell types and the movement of fluid across a variety of epithelial or endothelial structures. As such, they should soon become invaluable targets for the treatment of various disorders including pain, epilepsy, brain edema, and hypertension. This review highlights the nature of these roles, the mechanisms at play, and the unresolved issues in the field.


Asunto(s)
Simportadores de Cloruro de Sodio-Potasio/metabolismo , Animales , Edema Encefálico/tratamiento farmacológico , Edema Encefálico/metabolismo , Edema Encefálico/patología , Cloruros/metabolismo , Epilepsia/tratamiento farmacológico , Epilepsia/metabolismo , Epilepsia/patología , Humanos , Hipertensión/tratamiento farmacológico , Hipertensión/metabolismo , Hipertensión/patología , Transporte Iónico , Dolor/tratamiento farmacológico , Dolor/metabolismo , Dolor/patología , Potasio/metabolismo , Sodio/metabolismo
3.
J Physiol ; 597(6): 1451-1465, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30659612

RESUMEN

In the early 80s, renal microperfusion studies led to the identification of a basolateral K+ -Cl- cotransport mechanism in the proximal tubule, thick ascending limb of Henle and collecting duct. More than ten years later, this mechanism was found to be accounted for by three different K+ -Cl- cotransporters (KCC1, KCC3 and KCC4) that are differentially distributed along the renal epithelium. Two of these isoforms (KCC1 and KCC3) were also found to be expressed in arterial walls, the myocardium and a variety of neurons. Subsequently, valuable insights have been gained into the molecular and physiological properties of the KCCs in both the mammalian kidney and cardiovascular system. There is now robust evidence indicating that KCC4 sustains distal renal acidification and that KCC3 regulates myogenic tone in resistance vessels. However, progress in understanding the functional significance of these transporters has been slow, probably because each of the KCC isoforms is not identically distributed among species and some of them share common subcellular localizations with other KCC isoforms or sizeable conductive Cl- pathways. In addition, the mechanisms underlying the process of K+ -Cl- cotransport are still ill defined. The present review focuses on the knowledge gained regarding the roles and properties of KCCs in renal and cardiovascular tissues.


Asunto(s)
Sistema Cardiovascular/metabolismo , Riñón/metabolismo , Simportadores de Cloruro de Sodio-Potasio/metabolismo , Animales , Cloruros/metabolismo , Humanos , Potasio/metabolismo , Simportadores de Cloruro de Sodio-Potasio/química , Simportadores de Cloruro de Sodio-Potasio/genética
4.
Curr Oncol ; 24(6): 367-373, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29270048

RESUMEN

BACKGROUND: Multiple clinical practice guidelines recommend rapid evaluation of patients with suspected lung cancer. It is uncertain whether delays in diagnosis and management have a negative effect on outcomes. METHODS: This retrospective study included 551 patients diagnosed with lung cancer through the diagnostic assessment program at the Institut universitaire de cardiologie et de pneumologie de Québec between September 2013 and March 2015. Median wait times between initial referral, diagnosis, and first treatment were calculated and compared with recommended targets. Analyses were performed to evaluate for specific factors associated with longer wait times and for the effect of delays on the outcomes of progression-free survival (pfs), relapse-free survival (rfs) after primary surgical resection, and overall survival (os). RESULTS: Most patients were investigated and treated within recommended targets. Of the entire cohort, 379 patients were treated at our institution. Of those 379 patients, 311 (82%) were treated within recommended targets. In comparing patients within and outside target times, the only statistically significant difference was found in the distribution of treatment modalities: patients meeting targets were more likely to be treated with surgery or chemotherapy rather than with radiation. The pfs on first treatment modality was influenced by clinical stage, but not by time to therapy [hazard ratio (hr): 1.10; p = 0.65]. The os for the entire cohort was also influenced by stage, but not by delays (hr: 1.04; p = 0.87). For the 209 patients treated by surgery with curative intent, a significant reduction in rfs was associated with male sex and TNM stage, but not with delays (hr: 1.11; p = 0.83). The os after primary surgical resection was also associated with TNM stage, but not with delays (hr: 1.82; p = 0.43). CONCLUSIONS: Recommended targets for wait times in the investigation and treatment of lung cancer can be achieved within a diagnostic assessment program. Compared with radiation treatment, treatment with surgery or chemotherapy is more likely to be completed within targets. Delays in investigation and treatment do not appear to negatively affect the clinical outcomes of os, rfs, and pfs. Prospective studies are needed to evaluate whether efficient work-up and treatment influence other important variables, such as quality of life, cost of care, and access to therapies while performance status is adequate.

5.
Philos Trans A Math Phys Eng Sci ; 373(2052)2015 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-26347534

RESUMEN

Ice-rafted sediments of Eurasian and North American origin are found consistently in the upper part (13 Ma BP to present) of the Arctic Coring Expedition (ACEX) ocean core from the Lomonosov Ridge, near the North Pole (≈88° N). Based on modern sea-ice drift trajectories and speeds, this has been taken as evidence of the presence of a perennial sea-ice cover in the Arctic Ocean from the middle Miocene onwards (Krylov et al. 2008 Paleoceanography 23, PA1S06. (doi:10.1029/2007PA001497); Darby 2008 Paleoceanography 23, PA1S07. (doi:10.1029/2007PA001479)). However, other high latitude land and marine records indicate a long-term trend towards cooling broken by periods of extensive warming suggestive of a seasonally ice-free Arctic between the Miocene and the present (Polyak et al. 2010 Quaternary Science Reviews 29, 1757-1778. (doi:10.1016/j.quascirev.2010.02.010)). We use a coupled sea-ice slab-ocean model including sediment transport tracers to map the spatial distribution of ice-rafted deposits in the Arctic Ocean. We use 6 hourly wind forcing and surface heat fluxes for two different climates: one with a perennial sea-ice cover similar to that of the present day and one with seasonally ice-free conditions, similar to that simulated in future projections. Model results confirm that in the present-day climate, sea ice takes more than 1 year to transport sediment from all its peripheral seas to the North Pole. However, in a warmer climate, sea-ice speeds are significantly faster (for the same wind forcing) and can deposit sediments of Laptev, East Siberian and perhaps also Beaufort Sea origin at the North Pole. This is primarily because of the fact that sea-ice interactions are much weaker with a thinner ice cover and there is less resistance to drift. We conclude that the presence of ice-rafted sediment of Eurasian and North American origin at the North Pole does not imply a perennial sea-ice cover in the Arctic Ocean, reconciling the ACEX ocean core data with other land and marine records.

6.
Curr Oncol ; 22(6): 412-6, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26715874

RESUMEN

BACKGROUND: Treatment of malignant pericardial effusion remains controversial, because no randomized controlled trials have been conducted to determine the best approach, and results of retrospective studies have been inconsistent. The objective of the present study was to compare pericardiocentesis and pericardiotomy with respect to efficacy for preventing recurrence, and to determine, for those two procedures, diagnostic yields, complication rates, and effects on survival. We also aimed to identify clinical and procedural factors that could predict effusion recurrence. METHODS: We retrospectively assessed 61 patients who underwent a procedure for treatment of a malignant pericardial effusion at the Institut universitaire de cardiologie et de pneumologie de Québec between February 2004 and September 2013. RESULTS: Pericardiocentesis was performed in 42 patients, and pericardiotomy, in 19 patients. The effusion recurrence rate was significantly higher in patients treated with pericardiocentesis than with pericardiotomy (31.0% vs. 5.3%, p = 0.046). The diagnostic yield of the procedures was not significantly different (92.9% vs. 86.7%, p = 0.6). The overall rate of complications was similar in the two groups, as was the median overall survival (2.4 months vs. 2.6 months, p = 0.5). In univariate analyses, the procedure type was the only predictor of recurrence that approached statistical significance. Age, sex, type of cancer, presence of effusion at the time of cancer diagnosis, prior chest irradiation, tamponade upon presentation, and total volume of fluid removed did not influence the recurrence rate. CONCLUSIONS: Compared with pericardiocentesis, pericardiotomy had higher success rate in preventing recurrence of malignant pericardial effusion, with similar diagnostic yields, complication rates, and overall survival.

7.
Curr Oncol ; 22(6): e435-42, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26715880

RESUMEN

BACKGROUND: Older patients are commonly excluded from clinical trials in esophageal and gastroesophageal junction (gej) cancer. High-level evidence to guide management in this group is lacking. In the present study, we compared outcomes and described tolerance for curative- and noncurative-intent treatments among patients 70 years of age and older. METHODS: We retrospectively reviewed all patients 70 years of age and older diagnosed with localized esophageal and gej cancer at our centre between 2005 and 2012. RESULTS: The 74 patients identified had a median age of 77 years. Of those patients, 62% received curative-intent treatment, consisting mostly of concomitant chemoradiation therapy (n = 43, 93%). Median overall survival for patients receiving curative-intent treatment was 18.6 months [95% confidence interval (ci): 13.0 to 28.0 months], with 23% being long-term survivors (95% ci: 11.3% to 36.7%). In contrast, patients receiving noncurative-intent treatment had a median overall survival of 8.8 months (95% ci: 6.7 to 11.9 months), with none being long-term survivors (p < 0.0001). Improvement of dysphagia was seen after curative (81%) or palliative radiotherapy (78%) in symptomatic patients, and toxicities were manageable. The odds of not receiving curative treatment was higher by a factor of 8.5 among patients 80 years of age or older compared with those 70-79 years of age (95% ci: 2.5 to 28.7). CONCLUSIONS: In managing older patients with esophageal and gej cancer, curative-intent treatment (compared with noncurative-intent treatment) leads to a significant survival benefit with a reasonable toxicity profile. Informed counselling of patients and their families about a curative treatment approach and efforts to increase awareness among oncology care providers are suggested.

8.
Environ Microbiol ; 16(6): 1668-81, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24020678

RESUMEN

Dissolved organic matter (DOM) and heterotrophic bacteria are highly diverse components of the ocean system, and their interactions are key in regulating the biogeochemical cycles of major elements. How chemical and phylogenetic diversity are linked remains largely unexplored to date. To investigate interactions between bacterial diversity and DOM, we followed the response of natural bacterial communities to two sources of phytoplankton-derived DOM over six bacterial generation times in continuous cultures. Analyses of total hydrolysable neutral sugars and amino acids, and ultrahigh resolution mass spectrometry revealed large differences in the chemical composition of the two DOM sources. According to 454 pyrosequences of 16S ribosomal ribonucleic acid genes, diatom-derived DOM sustained higher levels of bacterial richness, evenness and phylogenetic diversity than cyanobacteria-derived DOM. These distinct community structures were, however, not associated with specific taxa. Grazing pressure affected bacterial community composition without changing the overall pattern of bacterial diversity levels set by DOM. Our results demonstrate that resource composition can shape several facets of bacterial diversity without influencing the phylogenetic composition of bacterial communities, suggesting functional redundancy at different taxonomic levels for the degradation of phytoplankton-derived DOM.


Asunto(s)
Bacteroidetes/genética , Proteobacteria/genética , Agua de Mar/microbiología , Cianobacterias/química , Diatomeas/química , Genes Bacterianos , Fenómenos Microbiológicos , Microbiota/genética , Compuestos Orgánicos/química , Compuestos Orgánicos/metabolismo , Filogenia , Fitoplancton/química , ARN Ribosómico 16S/genética , Agua de Mar/química , Soluciones
10.
Mar Pollut Bull ; 173(Pt A): 112896, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34601248

RESUMEN

Profiles of 33 PFAS analytes and 12 essential and non-essential trace elements were measured in livers of stranded common dolphins (Delphinus delphis) from New Zealand. PFAS concentrations reported were largely comparable to those measured in other marine mammal species globally and composed mostly of long-chain compounds including perfluorooctanesulfonic acid (PFOS), perfluorododecanoic acid (PFDoDA), perfluorotridecanoic acid (PFTrDA) and perfluorooctanesulfonamide (FOSA). PFAS profiles did not vary significantly by location, body condition, or life history. Notably, significant positive correlations were observed within respective PFAS and trace elements. However, only negative correlations were evident between these two contaminant types, suggesting different exposure and metabolic pathways. Age-associated concentrations were found for PFTrDA and four trace elements, i.e. silver, mercury, cadmium, selenium, indicating differences in the bioaccumulation biomagnification mechanisms. Overall, our results contribute to global understanding of accumulation of PFAS by offering first insights of PFAS exposure in cetaceans living within South Pacific Australasian waters.


Asunto(s)
Ácidos Alcanesulfónicos , Delfín Común , Fluorocarburos , Oligoelementos , Animales , Monitoreo del Ambiente , Fluorocarburos/análisis , Nueva Zelanda , Oligoelementos/análisis
11.
Acta Crystallogr Sect F Struct Biol Cryst Commun ; 65(Pt 11): 1071-7, 2009 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-19923721

RESUMEN

Unlike mammals, bacteria encode enzymes that synthesize branched-chain amino acids. The pyridoxal 50-phosphate-dependent transaminase performs the final biosynthetic step in these pathways, converting keto acid precursors into -amino acids. The branched-chain amino-acid transaminase from Mycobacterium tuberculosis (MtIlvE) has been crystallized and its structure has been solved at 1.9 angstrom resolution. The MtIlvE monomer is composed of two domains that interact to form the active site. The biologically active form of IlvE is a homodimer in which each monomer contributes a substrate-specificity loop to the partner molecule. Additional substrate selectivity may be imparted by a conserved N-terminal Phe30 residue, which has previously been observed to shield the active site in the type IV fold homodimer. The active site of MtIlvE contains density corresponding to bound PMP, which is likely to be a consequence of the presence of tryptone in the crystallization medium. Additionally, two cysteine residues are positioned at the dimer interface for disulfide-bond formation under oxidative conditions. It is unknown whether they are involved in any regulatory activities analogous to those of the human mitochondrial branched-chain amino-acid transaminase.


Asunto(s)
Proteínas Bacterianas/química , Mycobacterium tuberculosis/enzimología , Estructura Cuaternaria de Proteína , Estructura Terciaria de Proteína , Transaminasas/química , Secuencia de Aminoácidos , Aminoácidos de Cadena Ramificada/metabolismo , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Dominio Catalítico , Cristalografía por Rayos X , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Multimerización de Proteína , Alineación de Secuencia , Transaminasas/genética , Transaminasas/metabolismo
12.
Ann Pharm Fr ; 67(5): 320-34, 2009 Sep.
Artículo en Francés | MEDLINE | ID: mdl-19695368

RESUMEN

Abnormal movements and behavioral disorders are characteristic manifestations observed in certain neuropsychiatric diseases such as Tourette's syndrome or Huntington Disease. Together with brain imaging findings, the clinical data could suggest a relationship with basal ganglia dysfunction. In the first part of this review, we recall the anatomic relationships existing, via segregated cortico-cortical circuits, between these structures and the cortical areas having motor and cognitive or motivational-emotional attributes. This structure suggests that in pathologies like Parkinson's or Huntington disease cognitive and motivational-emotional disorders as well motor disturbances could be related to lesions or dysfunctions involving individual or combined zones of the basal ganglia. The second part of the paper focuses on a description of the various methodologies used to explore these relationships: behavioral, anatomic and brain imaging methods are used in non-human primate models in order to reproduce motor and behavioral disturbances and to determine the neuronal circuits involved. Microinjection of bicucullin into the external globus pallidus has been found to induce localized and reversible neuronal activation. Abnormal movements can be obtained from the motor territory of the external globus pallidus whereas hyperactivity with attentional deficit or stereotypies have been obtained from the associative or limbic territory of the same structure. In the striatum, the same pharmacological activation can induce either abnormal movements from motor and associative functional territories or behavioural changes with hyperactivity or, on the contrary, hypoactivity from associative functional territory with stereotyped behavior and sexual manifestations when the microinjections were done in the limbic striatum. Anatomic studies as well as brain imaging using PET confirm the involvement of segregated anatomic pathways through the basal ganglia in behavioral as well as motor disorders.


Asunto(s)
Enfermedades de los Ganglios Basales/patología , Ganglios Basales/patología , Trastornos Mentales/patología , Animales , Mapeo Encefálico , Modelos Animales de Enfermedad , Humanos , Hipercinesia/etiología , Hipercinesia/patología , Trastornos del Movimiento/etiología , Trastornos del Movimiento/patología
13.
J Hematol Oncol ; 12(1): 74, 2019 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-31296230

RESUMEN

During the 1970s, a Na+-independent, ouabain-insensitive, N-ethylmaleimide-stimulated K+-Cl- cotransport mechanism was identified in red blood cells for the first time and in a variety of cell types afterward. During and just after the mid-1990s, three closely related isoforms were shown to account for this mechanism. They were termed K+-Cl- cotransporter 1 (KCC1), KCC3, and KCC4 according to the nomenclature of Gillen et al. (1996) who had been the first research group to uncover the molecular identity of a KCC, that is, of KCC1 in rabbit kidney. Since then, KCC1 has been found to be the most widely distributed KCC isoform and considered to act as a housekeeping membrane protein. It has perhaps received less attention than the other isoforms for this reason, but as will be discussed in the following review, there is probably more to KCC1 than meets the eye. In particular, the so-called housekeeping gene also appears to play crucial and specific roles in normal as well as pathological hematopoietic and in cancer cells.


Asunto(s)
Hematopoyesis , Neoplasias/metabolismo , Simportadores/metabolismo , Animales , Humanos , Neoplasias/patología , Isoformas de Proteínas/análisis , Isoformas de Proteínas/metabolismo , Simportadores/análisis , Cotransportadores de K Cl
14.
Biochemistry ; 47(50): 13326-35, 2008 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-19053270

RESUMEN

Mycobacterium smegmatis MshC catalyzes the ATP-dependent condensation of GlcN-Ins and l-cysteine to form l-Cys-GlcN-Ins, the penultimate step in mycothiol biosynthesis. Attempts to crystallize the native, full-length MshC have been unsuccessful. However, incubation of the enzyme with the cysteinyl adenylate analogue, 5'-O-[N-(l-cysteinyl)-sulfamonyl]adenosine (CSA), followed by a 24-h limited trypsin proteolysis yielded an enzyme preparation that readily crystallized. The three-dimensional structure of MshC with CSA bound in the active site was solved and refined to 1.6 A. The refined structure exhibited electron density corresponding to the entire 47 kDa MshC molecule, with the exception of the KMSKS loop (residues 285-297), a loop previously implicated in the formation of the adenylate in related tRNA synthases. The overall tertiary fold of MshC is similar to that of cysteinyl-tRNA synthetase, with a Rossmann fold catalytic domain. The interaction of the thiolate of CSA with a zinc ion at the base of the active site suggests that the metal ion participates in amino acid binding and discrimination. A number of active site residues were observed to interact with the ligand, suggesting a role in substrate binding and catalysis. Analysis utilizing modeling of the proteolyzed loop and GlcN-Ins docking, as well as the examination of sequence conservation in the active site suggests similarities and differences between cysteinyl-tRNA synthetases and MshC in recognition of the substrates for their respective reactions.


Asunto(s)
Proteínas Bacterianas/química , Ligasas de Carbono-Nitrógeno/química , Cisteína/biosíntesis , Cisteína/química , Glicopéptidos/biosíntesis , Glicopéptidos/química , Inositol/biosíntesis , Inositol/química , Mycobacterium smegmatis/enzimología , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/metabolismo , Sitios de Unión , Ligasas de Carbono-Nitrógeno/biosíntesis , Ligasas de Carbono-Nitrógeno/metabolismo , Secuencia Conservada , Cristalización , Cristalografía por Rayos X , Cisteína/metabolismo , Glicopéptidos/metabolismo , Hidrólisis , Inositol/metabolismo , Unión Proteica , Estructura Secundaria de Proteína , Especificidad por Sustrato , Tripsina/metabolismo
15.
J Clin Invest ; 99(5): 944-52, 1997 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-9062352

RESUMEN

We examined the effect of ventilation strategy on lung inflammatory mediators in the presence and absence of a preexisting inflammatory stimulus. 55 Sprague-Dawley rats were randomized to either intravenous saline or lipopolysaccharide (LPS). After 50 min of spontaneous respiration, the lungs were excised and randomized to 2 h of ventilation with one of four strategies: (a) control (C), tidal volume (Vt) = 7 cc/kg, positive end expiratory pressure (PEEP) = 3 cm H2O; (b) moderate volume, high PEEP (MVHP), Vt = 15 cc/kg; PEEP = 10 cm H2O; (c) moderate volume, zero PEEP (MVZP), Vt = 15 cc/kg, PEEP = 0; or (d) high volume, zero PEEP (HVZP), Vt = 40 cc/kg, PEEP = 0. Ventilation with zero PEEP (MVZP, HVZP) resulted in significant reductions in lung compliance. Lung lavage levels of TNFalpha, IL-1beta, IL-6, IL-10, MIP-2, and IFNgamma were measured by ELISA. Zero PEEP in combination with high volume ventilation (HVZP) had a synergistic effect on cytokine levels (e.g., 56-fold increase of TNFalpha versus controls). Identical end inspiratory lung distention with PEEP (MVHP) resulted in only a three-fold increase in TNFalpha, whereas MVZP produced a six-fold increase in lavage TNFalpha. Northern blot analysis revealed a similar pattern (C, MVHP < MVZP < HVZP) for induction of c-fos mRNA. These data support the concept that mechanical ventilation can have a significant influence on the inflammatory/anti-inflammatory milieu of the lung, and thus may play a role in initiating or propagating a local, and possibly systemic inflammatory response.


Asunto(s)
Pulmón/inmunología , Pulmón/patología , Respiración con Presión Positiva/efectos adversos , Animales , Northern Blotting , Líquido del Lavado Bronquioalveolar/química , Quimiocina CCL4 , Ensayo de Inmunoadsorción Enzimática , Genes fos , Inflamación/inmunología , Interferón gamma/análisis , Interferón gamma/inmunología , Interleucina-1/análisis , Interleucina-1/inmunología , Interleucina-10/análisis , Interleucina-10/inmunología , Interleucina-6/análisis , Interleucina-6/inmunología , Lipopolisacáridos/farmacología , Rendimiento Pulmonar , Proteínas Inflamatorias de Macrófagos/análisis , Proteínas Inflamatorias de Macrófagos/inmunología , Masculino , Respiración con Presión Positiva/métodos , Proteínas/análisis , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/análisis , Factor de Necrosis Tumoral alfa/inmunología
17.
Sci Total Environ ; 355(1-3): 135-44, 2006 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-16442435

RESUMEN

We report the results of a recent survey of the concentration of natural estrogens (17beta-estradiol, 17alpha-estradiol, estrone, estriol) and the synthetic estrogen, 17alpha-ethynylestradiol in representative animal wastes and sewage treatment plant (STP) effluents in the Waikato region of New Zealand. Dairy farm effluent samples showed high levels of estradiol (19-1360 ng/L) and its breakdown product estrone (41-3123 ng/L) compared with piggery or goat farm effluents. The combined load for these estrogens (excluding beta epimer) varied from 60 to >4000 ng/L. The piggery effluent provided the lowest total estrogen load (46 ng/L), with estrone accounting for nearly 60% of the measured estrogens in this sample. The synthetic analogue, 17alpha-ethynylestradiol was detected only in one wastewater treatment plant sample, albeit at trace level. An estrogen receptor competitive binding assay was used to test the biological activity of the samples and confirmed that most agricultural waste samples contain high levels of estrogenic compounds. The potential of these wastes to cause endocrine disruption in the receiving ecosystem is unknown at present.


Asunto(s)
Estradiol/análisis , Estrona/análisis , Estiércol/análisis , Aguas del Alcantarillado/análisis , Crianza de Animales Domésticos , Animales , Unión Competitiva , Bovinos , Industria Lechera , Disruptores Endocrinos/análisis , Monitoreo del Ambiente , Estradiol/metabolismo , Estrógenos/análisis , Estrógenos/metabolismo , Estrona/metabolismo , Cabras , Nueva Zelanda , Receptores de Estrógenos/metabolismo , Porcinos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo
19.
J Geophys Res Oceans ; 121(12): 8635-8669, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32818130

RESUMEN

The relative skill of 21 regional and global biogeochemical models was assessed in terms of how well the models reproduced observed net primary productivity (NPP) and environmental variables such as nitrate concentration (NO3), mixed layer depth (MLD), euphotic layer depth (Zeu), and sea ice concentration, by comparing results against a newly updated, quality-controlled in situ NPP database for the Arctic Ocean (1959-2011). The models broadly captured the spatial features of integrated NPP (iNPP) on a pan-Arctic scale. Most models underestimated iNPP by varying degrees in spite of overestimating surface NO3, MLD, and Zeu throughout the regions. Among the models, iNPP exhibited little difference over sea ice condition (ice-free versus ice-influenced) and bottom depth (shelf versus deep ocean). The models performed relatively well for the most recent decade and toward the end of Arctic summer. In the Barents and Greenland Seas, regional model skill of surface NO3 was best associated with how well MLD was reproduced. Regionally, iNPP was relatively well simulated in the Beaufort Sea and the central Arctic Basin, where in situ NPP is low and nutrients are mostly depleted. Models performed less well at simulating iNPP in the Greenland and Chukchi Seas, despite the higher model skill in MLD and sea ice concentration, respectively. iNPP model skill was constrained by different factors in different Arctic Ocean regions. Our study suggests that better parameterization of biological and ecological microbial rates (phytoplankton growth and zooplankton grazing) are needed for improved Arctic Ocean biogeochemical modeling.

20.
Biochim Biophys Acta ; 1108(2): 183-9, 1992 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-1637843

RESUMEN

Tyrosine protein kinase (TPK) activity was detected in rat renal brush-border membranes (BBM) using poly(Glu80Na,Tyr20) as a substrate. Maximal TPK activity required prior detergent dispersion of the membranes with 0.05% Triton X-100 and the presence of vanadate, a potent inhibitor of phosphotyrosine protein phosphatases, in the phosphorylation medium. Optimal conditions for measurement of TPK activity were 10 mM of MgCl2 and MnCl2, at 30 degrees C and pH 7.0. TPK activity was inhibited by genistein, with a IC50 value of 15 microM, while no inhibition was observed in the presence of 1-(5-isoquinolinesulfonyl)-2-methyl-piperazine dihydrochloride (H7), an inhibitor of serine-threonine kinases. TPK activity was enriched 4-fold in the BBM fraction relative to cortex homogenate. It was co-enriched with BBM enzyme markers, but not with those of the basolateral membrane (BLM). The endogenous substrates of TPK in brush-border and basolateral membranes were determined by Western blot analysis using an antiphosphotyrosine monoclonal antibody (PY20). Various phosphotyrosine-containing proteins were found in the BBM (31, 34, 46, 50, 53, 72, 90, 118 and 170 kDa) and in the BLM (37, 48, 50, 53, 72, 90, 130 and 170 kDa). Addition of exogenous insulin receptor to BBM and BLM increased the phosphorylation of most of the substrates. Solubilization of the TPK activity from BBM with 0.5% CHAPS and subsequent gel filtration on Superdex 75 yielded two peaks of tyrosine protein kinase activity with apparent molecular masses of 49 and 66 kDa. These results provide evidence for a non-receptor TPK activity associated with the renal tubular luminal membrane.


Asunto(s)
Túbulos Renales Proximales/enzimología , Proteínas de la Membrana/metabolismo , Microvellosidades/enzimología , Proteínas Tirosina Quinasas/metabolismo , Animales , Células Cultivadas , Éteres Cíclicos/farmacología , Masculino , Octoxinol , Ácido Ocadaico , Fosforilación , Polietilenglicoles/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Ratas , Ratas Endogámicas , Vanadatos/farmacología
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