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1.
Nature ; 607(7918): 301-306, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35831604

RESUMEN

Our understanding of the climatic teleconnections that drove ice-age cycles has been limited by a paucity of well-dated tropical records of glaciation that span several glacial-interglacial intervals. Glacial deposits offer discrete snapshots of glacier extent but cannot provide the continuous records required for detailed interhemispheric comparisons. By contrast, lakes located within glaciated catchments can provide continuous archives of upstream glacial activity, but few such records extend beyond the last glacial cycle. Here a piston core from Lake Junín in the uppermost Amazon basin provides the first, to our knowledge, continuous, independently dated archive of tropical glaciation spanning 700,000 years. We find that tropical glaciers tracked changes in global ice volume and followed a clear approximately 100,000-year periodicity. An enhancement in the extent of tropical Andean glaciers relative to global ice volume occurred between 200,000 and 400,000 years ago, during sustained intervals of regionally elevated hydrologic balance that modified the regular approximately 23,000-year pacing of monsoon-driven precipitation. Millennial-scale variations in the extent of tropical Andean glaciers during the last glacial cycle were driven by variations in regional monsoon strength that were linked to temperature perturbations in Greenland ice cores1; these interhemispheric connections may have existed during previous glacial cycles.

2.
Osteoporos Int ; 29(12): 2781-2789, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30143849

RESUMEN

Osteogenesis imperfecta (OI) is a disease causing bone fragility; however, it potentially affects all organs with a high content of collagen, including ears, teeth, and eyes. The study is cross-sectional and compares non-skeletal characteristics in adults with OI that clinicians should be aware of when caring for patients with OI. INTRODUCTION: Osteogenesis imperfecta (OI) is a hereditary connective tissue disorder. The skeletal fragility is pronounced; however, OI leads to a number of extra-skeletal symptoms related to the ubiquity of collagen type 1 throughout the human body. The vast majority of knowledge is derived from studies performed in the pediatric population. Thus, we aimed to investigate the nature and prevalence of ophthalmologic, odontologic, and otologic phenotypes in an adult population with OI. METHODS: The study population comprises 85 Danish OI patients (age 44.9 ± 15.9 years). Fifty-eight patients had OI type I, 12 OI type III, and 15 OI type IV according to the classification by Sillence. Audiometric evaluations and dental examinations were performed in 62 and 73 patients, respectively. Ophthalmologic investigations were performed in 64 patients, including measurements of the central corneal thickness. RESULTS: All patients, except two, had corneal thickness below the normal reference value. Patients with OI type I and patients with a quantitative collagen defect had thinner corneas compared to patients with OI type III and other patients with a qualitative collagen defect. One patient in this cohort was diagnosed with and treated for acute glaucoma. Dentinogenesis imperfecta was diagnosed in one fourth of the patients, based on clinical and radiographic findings. This condition was predominately seen in patients with moderate to severe OI. Hearing loss requiring treatment was found in 15 of 62 patients, of whom three were untreated. The most prevalent type of hearing loss (HL) was sensorineural hearing loss, whereas conductive HL was solely seen in patients with OI type III. The patients with the most severe degrees of HL were patients with mild forms of OI. Age was associated with increased HL. CONCLUSION: Although significant health problems outside the skeleton are frequent in adult patients with OI, the patients are not consistently monitored and treated for their symptoms. Clinicians treating adult patients with OI should be aware of non-skeletal health issues and consider including regular interdisciplinary check-ups in the management plan for adult OI patients.


Asunto(s)
Dentinogénesis Imperfecta/diagnóstico , Enfermedades Hereditarias del Ojo/diagnóstico , Pérdida Auditiva/diagnóstico , Osteogénesis Imperfecta/diagnóstico , Adulto , Anciano , Dinamarca/epidemiología , Dentinogénesis Imperfecta/epidemiología , Enfermedades Hereditarias del Ojo/epidemiología , Femenino , Pérdida Auditiva/epidemiología , Pérdida Auditiva/etiología , Humanos , Masculino , Persona de Mediana Edad , Osteogénesis Imperfecta/complicaciones , Osteogénesis Imperfecta/epidemiología , Fenotipo , Adulto Joven
3.
Vet Parasitol ; 238: 87-89, 2017 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-28408213

RESUMEN

A fixed-combination chewable tablet incorporating afoxolaner plus milbemycin oxime (NexGard Spectra®, Merial) was tested in purpose-bred Beagle dogs for efficacy against adult Ancylostoma ceylanicum hookworms. Sixteen dogs were inoculated each by oral administration of approximately 500 infective larvae of A. ceylanicum. Seventeen days after inoculation, the dogs were weighed and allocated randomly to be treated with afoxolaner plus milbemycin oxime chewable tablets or to remain untreated. Commercial chewable tablets of different strength were combined to deliver doses as close as possible to the minimum effective dose of 2.5mg afoxolaner plus 0.5mg milbemycin oxime per kg body weight. Parasites were recovered and counted for determination of efficacy seven days after treatment. All eight dogs that had been left untreated were harboring adult A. ceylanicum (geometric mean, 317.8; range, 210-428) while only one and nine A. ceylanicum were recovered from two of the eight dogs treated with afoxolaner plus milbemycin oxime chewable tablets (geometric mean, 0.5; p<0.0001). Thus, 99.9% efficacy against induced infection of A. ceylanicum was obtained by the use of oral NexGard Spectra® at the minimum effective dose. Treatment with afoxolaner plus milbemycin oxime chewable tablets was well accepted and safe.


Asunto(s)
Ancylostoma/efectos de los fármacos , Anquilostomiasis/veterinaria , Enfermedades de los Perros/parasitología , Isoxazoles/uso terapéutico , Macrólidos/uso terapéutico , Naftalenos/uso terapéutico , Anquilostomiasis/tratamiento farmacológico , Animales , Antihelmínticos/administración & dosificación , Antihelmínticos/uso terapéutico , Enfermedades de los Perros/tratamiento farmacológico , Perros , Combinación de Medicamentos , Femenino , Isoxazoles/administración & dosificación , Macrólidos/administración & dosificación , Masculino , Naftalenos/administración & dosificación , Comprimidos
4.
J Vet Pharmacol Ther ; 40(5): 447-453, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27891622

RESUMEN

The safety profile of afoxolaner (an isoxazoline molecule) when combined with milbemycin oxime (a macrocyclic lactone) was evaluated according to the regulatory requirements when administered six times orally in a soft chewable formulation at a dose of at least 1×, 3×, or 5× the maximum exposure dose in 8-week-old Beagle dogs. Thirty-two healthy puppies (16 males and 16 females) were enrolled and allocated randomly to one of four treatment groups. Three doses were administered at 28-day intervals (Days 0, 28, and 56), followed by three additional doses administered with 14-day intervals (Days 84, 98, and 112). The study ended on Day 126. Treatment groups were as follows: Group 1: untreated, sham-dosed control; Group 2: afoxolaner/milbemycin oxime chews administered at a dose of at least 5 and 1 mg/kg, respectively (1×); Group 3: afoxolaner/milbemycin oxime chews administered at a dose of at least 15 and 3 mg/kg, respectively (3); and Group 4: afoxolaner/milbemycin oxime chews administered at a dose of at least 25 and 5 mg/kg, respectively (5×). All dogs were examined for general health twice a day beginning on Day -14. Physical examinations, and blood collections for clinical pathology analysis and afoxolaner and milbemycin oxime plasma concentrations, were performed throughout the study. No afoxolaner/milbemycin oxime treatment-related changes were observed in growth, physical variables, clinical pathology variables, or tissues examined histologically. No clinically relevant or statistically significant health abnormalities related to the administration of afoxolaner/milbemycin oxime were observed. No signs of macrocyclic lactone sensitivity were observed at any time during the study. Vomiting and diarrhea were observed sporadically across all groups including the controls. Based upon the results of this study, afoxolaner/milbemycin oxime soft chewables were shown to be safe when administered repeatedly at up to 5× the maximum exposure dose in dogs as young as 8 weeks of age.


Asunto(s)
Antiparasitarios/administración & dosificación , Enfermedades de los Perros/prevención & control , Isoxazoles/administración & dosificación , Macrólidos/administración & dosificación , Naftalenos/administración & dosificación , Administración Oral , Animales , Antiparasitarios/efectos adversos , Perros , Femenino , Isoxazoles/efectos adversos , Macrólidos/efectos adversos , Masculino , Naftalenos/efectos adversos
5.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-666617

RESUMEN

G protein-coupled receptors (GPCRs) convert extracellular stimuli in the form of hormones, odorants and light into profound changes in cell homeostasis. Their timely desensitization is critical for cells to rapidly respond to changes in their environment and to avoid damage from sustained signaling. Seven GPCR kinases (GRKs) phosphorylate and regulate the activity of most of the ~800 GPCRs in the human genome. Although GRKs normally play an adaptive role, in conditions such as chronic heart failure they are overexpressed and linked to disease progression. GRK2 and GRK5 have thus become important targets for the treatment of heart failure and pathological cardiac hypertrophy, respectively. Our lab has determined atomic structures representing all three vertebrate GRK subfamilies, and is now in the midst of a campaign to develop selective inhibitors of these enzymes using structure-based rational design. We have identified the FDA approved drug paroxetine as a selective GRK2 inhibitor, determined the crystal structure of the GRK2·paroxetine complex and, in collaboration with the Koch lab, showed that the drug improves contractility in myocytes and, most impressively, recovery in post-myocardial infarcted mice. Since then, we have identified additional chemical scaffolds that exhibit even higher potency and/or selectivity for GRK5. Using a ″hybrid″ inhibitor design approach we have generated GRK selective chemical probes that exhibit improved potency and stability and are able to increase inotropy and dampen the hypertrophic response in cardiomyocytes and small animal models. Structural analysis has revealed the molecular basis for selectivity and potency in many of these compounds, allowing for the design of future generations of GRK chemical probes.

6.
Artículo en Inglés | MEDLINE | ID: mdl-27865266

RESUMEN

A randomized, blinded, negative controlled study was conducted to determine whether treatment with afoxolaner (NexGard®, Merial, Inc.) would prevent the transmission of Borrelia burgdorferi to dogs by wild caught Ixodes scapularis ticks. Twenty healthy dogs were randomly assigned to two groups of ten dogs each. Ten dogs were treated orally on Day 0 at a dose near the minimum recommended dose of afoxolaner of 2.5mg/kg (actual doses 2.5-3.1mg/kg) and ten control dogs were not treated. On Day 28, each dog was infested with approximately 50 adult unfed wild caught I. scapularis that had a 67% B. burgdorferi infection rate (determined by polymerase chain reaction). On Day 33, live ticks were counted and removed. No ticks were found on treated dogs while control dogs had an average of 21.4 ticks. To detect infection, the B. burgdorferi-specific C6 antibody SNAP® 4Dx® test (IDEXX) was performed on serum collected before infestation (all dogs seronegative on Days -6 and 27) and on Days 48, 63, 77 and 92. The ten treated dogs remained seronegative through the end of the study (Day 92), while nine out of the ten control dogs were infected, as demonstrated by their seroconversion to being positive for the presence of the B. burgdorferi-specific C6 antibody starting on Day 48. In this study, all dogs treated with NexGard® 28days prior to challenge with wild caught I. scapularis ticks were protected from B. burgdorferi infection, while nine out of the ten untreated control dogs were infected.


Asunto(s)
Acaricidas/administración & dosificación , Enfermedades de los Perros/prevención & control , Isoxazoles/administración & dosificación , Ixodes/microbiología , Enfermedad de Lyme/veterinaria , Naftalenos/administración & dosificación , Infestaciones por Garrapatas/veterinaria , Administración Oral , Animales , Anticuerpos Antibacterianos/sangre , Borrelia burgdorferi/genética , Borrelia burgdorferi/inmunología , Borrelia burgdorferi/aislamiento & purificación , Enfermedades de los Perros/microbiología , Perros , Enfermedad de Lyme/microbiología , Enfermedad de Lyme/prevención & control , Enfermedad de Lyme/transmisión , Infestaciones por Garrapatas/prevención & control
7.
Biochemistry ; 53(20): 3318-26, 2014 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-24804868

RESUMEN

The exo-1,3-ß-glucanase (Exg) from Candida albicans is involved in cell wall ß-d-glucan metabolism and morphogenesis through its hydrolase and transglycosidase activities. Previous work has shown that both these activities strongly favor ß-1,3-linkages. The E292S Exg variant displayed modest glycosynthase activity using α-d-glucopyranosyl fluoride (α-GlcF) as the donor and pNP-ß-d-glucopyranoside (pNPGlc) as the acceptor but surprisingly showed a marked preference for synthesizing ß-1,6-linked over ß-1,3- and ß-1,4-linked disaccharide products. With pNPXyl as the acceptor, the preference became ß-1,4 over ß-1,3. The crystal structure of the glycosynthase bound to both of its substrates, α-GlcF and pNPGlc, is the first such ternary complex structure to be determined. The results revealed that the donor bound in the -1 subsite, as expected, while the acceptor was oriented in the +1 subsite to facilitate ß-1,6-linkage, thereby supporting the results from solution studies. A second crystal structure containing the major product of glycosynthesis, pNP-gentiobiose, showed that the -1 subsite allows another docking position for the terminal sugar; i.e., one position is set up for catalysis, whereas the other is an intermediate stage prior to the displacement of water from the active site by the incoming sugar hydroxyls. The +1 subsite, an aromatic "clamp", permits several different sugar positions and orientations, including a 180° flip that explains the observed variable regiospecificity. The p-nitrophenyl group on the acceptor most likely influences the unexpectedly observed ß-1,6-specificity through its interaction with F229. These results demonstrate that tailoring the specificity of a particular glycosynthase depends not only on the chemical structure of the acceptor but also on understanding the structural basis of the promiscuity of the native enzyme.


Asunto(s)
Candida albicans/enzimología , Proteínas Fúngicas/química , Glucano 1,3-beta-Glucosidasa/química , Glucógeno Sintasa/química , Cristalografía por Rayos X , Proteínas Fúngicas/metabolismo , Glucano 1,3-beta-Glucosidasa/metabolismo , Glucógeno Sintasa/metabolismo , Estructura Secundaria de Proteína , Especificidad por Sustrato/fisiología
8.
J Prev Alzheimers Dis ; 1(2): 91-98, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-28529932

RESUMEN

BACKGROUND: Internet-based educational interventions may be useful for impacting knowledge and behavioral change. However, in AD prevention, little data exists about which educational tools work best in terms of learning and interest in participating in clinical trials. OBJECTIVES: Primary: Assess effectiveness of interactive webinars vs. written blog-posts on AD prevention learning. Secondary: Evaluate the effect of AD prevention education on interest in participating in clinical trials; Assess usability of, and user perceptions about, an online AD education research platform; Classify target populations (demographics, learning needs, interests). DESIGN: Observational. SETTING: Online. PARTICIPANTS: Men/Women, aged 25+, recruited via facebook.com. INTERVENTION: Alzheimer's Universe (www.AlzU.org) education research platform. MEASUREMENTS: Pre/post-test performance, self-reported Likert-scale ratings, completion rates. RESULTS: Over two-weeks, 4268 visits were generated. 503 signed-up for a user account (11.8% join rate), 196 participated in the lessons (39.0%) and 100 completed all beta-testing steps (19.9%). Users randomized to webinar instruction about AD prevention and the stages of AD demonstrated significant increases (p=0.01) in pre vs. post-testing scores compared to blog-post intervention. Upon joining, 42% were interested in participating in a clinical trial in AD prevention. After completing all beta-test activities, interest increased to 86%. Users were primarily women and the largest category was children of AD patients. 66.3% joined to learn more about AD prevention, 65.3% to learn more about AD treatment. CONCLUSIONS: Webinar-based education led to significant improvements in learning about AD prevention and the stages of AD. AlzU.org participation more than doubled interest in AD prevention clinical trial participation. Subjects were quickly and cost-effectively recruited, and highly satisfied with the AD education research platform. Based on these data, we will further refine AlzU.org prior to public launch and aim to study the effectiveness of 25 interactive webinar-based vs. blog-post style lessons on learning and patient outcomes, in a randomized, within-subjects design trial.

9.
Haemophilia ; 19(4): 590-4, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23496210

RESUMEN

Type 2M von Willebrand disease (VWD) includes qualitative defects in von Willebrand factor (VWF) function, with normal multimer distribution but a defect in VWF activity with respect to platelet or collagen binding. We characterized novel VWF gene mutations found in type 2M VWD subjects enrolled in the Zimmerman Program for the Molecular and Clinical Biology of VWD. Subjects were enrolled based on a pre-existing diagnosis of type 2M VWD. Testing included full-length gene sequencing, VWF antigen (VWF:Ag), VWF ristocetin cofactor activity (VWF:RCo), VWF collagen binding and multimer distribution. Recombinant VWF variants were synthesized using site-directed mutagenesis and expressed in HEK293T cells. Platelet binding was measured by flow cytometry with fixed platelets and ELISA with recombinant glycoprotein Ibα (GPIbα). Four novel VWF A1 domain mutations were found in individuals with type 2M VWD: S1358N, S1387I, S1394F and Q1402P. All subjects had a history of bleeding, VWF:RCo < 40 IU dL(-1) , VWF:RCo/VWF:Ag ratios <0.6 and normal multimer distribution. No defect in expression, secretion, or multimerization was found for any of the mutations. All showed decreased binding to intact platelets, and decreased or absent binding to a mutant GPIbα construct with spontaneous VWF binding. 1387I had decreased binding to all collagen types tested. 1402P had reduced binding exclusively to type VI collagen. Type 2M VWD is a heterogeneous category comprised of both collagen- and platelet-binding defects. Understanding the precise defect for each mutation may ultimately lead to better diagnosis and treatment.


Asunto(s)
Plaquetas/metabolismo , Colágeno/metabolismo , Enfermedad de von Willebrand Tipo 2/genética , Plaquetas/efectos de los fármacos , Femenino , Células HEK293 , Humanos , Proteínas Mutantes/metabolismo , Mutación/genética , Complejo GPIb-IX de Glicoproteína Plaquetaria/metabolismo , Unión Proteica/efectos de los fármacos , Multimerización de Proteína/efectos de los fármacos , Proteínas Recombinantes/metabolismo , Ristocetina/farmacología , Factor de von Willebrand/genética
10.
Clin Biochem ; 45(7-8): 541-6, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22382088

RESUMEN

OBJECTIVES: Type V collagen has been demonstrated to control fibril formation. The aim of this study was to develop an ELISA capable of detecting a fragment of type V collagen generated by MMP-2/9 and to evaluate the assay as biomarker for ankylosing spondylitis (AS). DESIGN AND METHODS: A fragment unique to type V collagen and generated by both MMP-2/9 cleaved at the amino acid position 1317 (C5M) was selected for ELISA development. 40 AS patients and 40 age-matched controls were evaluated. RESULTS: An ELISA detecting C5M with inter- and intra-assay variations of 9.1% and 4.4% was developed. C5M levels were significantly higher in AS patients compared to controls, 229% (p<0.0001). The diagnostic AUC was 83%. CONCLUSIONS: This ELISA is the first for detecting type V collagen degradation. AS patients had highly elevated levels of MMP mediated type V collagen degradation. The prognostic and diagnostic values need to be further investigated in additional clinical settings.


Asunto(s)
Colágeno Tipo VI/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Espondilitis Anquilosante/patología , Adolescente , Adulto , Anciano , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/metabolismo , Biomarcadores/sangre , Biomarcadores/metabolismo , Estudios de Casos y Controles , Colágeno Tipo VI/metabolismo , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Fragmentos de Péptidos , Pronóstico , Proteolisis , Estudios Retrospectivos , Espondilitis Anquilosante/diagnóstico , Espondilitis Anquilosante/metabolismo , Adulto Joven
11.
Clin Exp Rheumatol ; 30(3): 371-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22339813

RESUMEN

OBJECTIVES: Ankylosing spondylitis (AS) is a chronic inflammation of the spine and the sacroiliac joints. Current markers of inflammation, such as C-reactive protein (CRP), are reflecting the production of an acute phase reactant rather than tissue specific inflammation, but the use of CRP as a diagnostic and prognostic marker for AS has not provided the sought accuracy and specificity. We hypothesized that local enzymatic activity in the disease-affected tissue, which is associated with extensive tissue turnover may, by cleavage, modify the CRP produced in the liver. These cleavage products may provide additional information on systemic inflammation as compared to that of full-length CRP. We investigated whether these CRP degradation products would provide additional diagnostic value in AS patients compared to full-length CRP. METHODS: CRP fragments were identified by mass-spectrometry. Two fragments were selected for ELISA development. One assay exclusively identified a matrix metalloproteinase (MMP) generated fragment, CRP-MMP, whereas the other assay identified a cathepsin generated fragment, CRP-CAT. Full-length CRP, CRP-MMP and CRP-CAT were measured in serum samples from 40 AS patients and 40 sex- and age-matched controls. RESULTS: Full-length CRP was not elevated in AS patients compared to controls, whereas CRP-MMP was elevated by 25% (p<0.001) and CRP-CAT by 50% (p<0.0001). The Area Under Curve of the Receiver-Operator Characteristic curve of CRP-CAT was the highest with 77%. CONCLUSIONS: MMP and cathepsin degraded CRP provided more discriminative diagnostic potential compared to that of full-length CRP in this current study. These data suggest that different pools of CRP may provide insight into the inflammation processes in AS.


Asunto(s)
Proteína C-Reactiva/inmunología , Catepsinas/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Inflamación , Metaloproteinasas de la Matriz/inmunología , Espondilitis Anquilosante , Anciano , Secuencia de Aminoácidos , Animales , Biomarcadores/sangre , Proteína C-Reactiva/química , Proteína C-Reactiva/metabolismo , Catepsinas/sangre , Diagnóstico Diferencial , Ensayo de Inmunoadsorción Enzimática/normas , Epítopos/sangre , Epítopos/inmunología , Femenino , Humanos , Inflamación/sangre , Inflamación/diagnóstico , Inflamación/inmunología , Masculino , Metaloproteinasas de la Matriz/sangre , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Fragmentos de Péptidos/química , Fragmentos de Péptidos/inmunología , Fragmentos de Péptidos/metabolismo , Curva ROC , Espondilitis Anquilosante/sangre , Espondilitis Anquilosante/diagnóstico , Espondilitis Anquilosante/inmunología
12.
Nat Med ; 17(12): 1674-9, 2011 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-22057346

RESUMEN

Osteoarthritis, characterized by the breakdown of articular cartilage in synovial joints, has long been viewed as the result of 'wear and tear'. Although low-grade inflammation is detected in osteoarthritis, its role is unclear. Here we identify a central role for the inflammatory complement system in the pathogenesis of osteoarthritis. Through proteomic and transcriptomic analyses of synovial fluids and membranes from individuals with osteoarthritis, we find that expression and activation of complement is abnormally high in human osteoarthritic joints. Using mice genetically deficient in complement component 5 (C5), C6 or the complement regulatory protein CD59a, we show that complement, specifically, the membrane attack complex (MAC)-mediated arm of complement, is crucial to the development of arthritis in three different mouse models of osteoarthritis. Pharmacological modulation of complement in wild-type mice confirmed the results obtained with genetically deficient mice. Expression of inflammatory and degradative molecules was lower in chondrocytes from destabilized joints from C5-deficient mice than C5-sufficient mice, and MAC induced production of these molecules in cultured chondrocytes. Further, MAC colocalized with matrix metalloprotease 13 (MMP13) and with activated extracellular signal-regulated kinase (ERK) around chondrocytes in human osteoarthritic cartilage. Our findings indicate that dysregulation of complement in synovial joints has a key role in the pathogenesis of osteoarthritis.


Asunto(s)
Complemento C5/metabolismo , Complejo de Ataque a Membrana del Sistema Complemento/metabolismo , Osteoartritis/metabolismo , Osteoartritis/patología , Animales , Antígenos CD59/genética , Antígenos CD59/metabolismo , Cartílago/metabolismo , Cartílago/patología , Condrocitos/metabolismo , Condrocitos/patología , Complemento C5/genética , Complemento C6/genética , Complemento C6/metabolismo , Modelos Animales de Enfermedad , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Articulaciones/metabolismo , Articulaciones/patología , Metaloproteinasa 13 de la Matriz/genética , Metaloproteinasa 13 de la Matriz/metabolismo , Ratones , Ratones Noqueados , Proteómica/métodos , Líquido Sinovial/metabolismo
13.
Clin Biochem ; 43(15): 1249-56, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20709044

RESUMEN

OBJECTIVES: The present study describes two newly developed N-terminal pro-peptides of collagen type I (PINP) competitive enzyme-linked immunosorbent assays (ELISAs) for the assessment of corresponding PINP epitopes in the rat- and human species. METHODS: Monoclonal antibodies were raised against corresponding rat and human PINP sequences and competitive assays were developed for each species. They were evaluated in relevant pre-clinical or clinical studies. RESULTS: The antibody characterizations indicated that PINP indeed was recognized. Technical robust assays were obtained. Rat PINP and tALP showed similar patterns in the gold standard osteoporosis rat ovariectomized (OVX) model. No liver contribution was observed in the liver fibrosis rat bile duct ligation model (BDL). In an osteoporosis study, the human serum PINP levels were significantly decreased after ibandronate treatment compared to placebo. CONCLUSIONS: The two corresponding PINP assays were specific and these bone turnover markers may improve translational science for the evaluation for bone-related diseases.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/métodos , Epítopos/inmunología , Fragmentos de Péptidos/sangre , Fragmentos de Péptidos/inmunología , Procolágeno/sangre , Procolágeno/inmunología , Anciano , Secuencia de Aminoácidos , Animales , Western Blotting , Conservadores de la Densidad Ósea/farmacología , Calibración , Células Clonales , Demografía , Difosfonatos/administración & dosificación , Difosfonatos/farmacología , Femenino , Humanos , Ácido Ibandrónico , Datos de Secuencia Molecular , Osteocalcina/sangre , Ovariectomía , Fragmentos de Péptidos/química , Placebos , Posmenopausia/sangre , Posmenopausia/efectos de los fármacos , Procolágeno/química , Ratas
14.
Clin Biochem ; 43(10-11): 899-904, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20380828

RESUMEN

OBJECTIVES: Accumulation of extracellular matrix (ECM) components and increased matrix-metalloprotease (MMPs) activity are hallmarks of fibrosis. We developed an ELISA for quantification of MMP-9 derived collagen type III (CO3) degradation. DESIGN AND METHODS: A monoclonal antibody targeting a specific MMP-9 cleaved fragment of CO3 was used for development of a competitive ELISA. The assay was investigated in serum and tissues from bile duct ligated rats (BDL). RESULTS: The ELISA showed no cross-reaction with either intact CO3, or other collagens. The intra- and inter-assay CV were below 10%. Liver fibrosis was demonstrated in BDL animals by semi quantitative scoring (P<0.0001). Serum levels of CO3-610 increased 2.5 fold in BDL animals (P<0.001). The CO3-610 levels were 5 fold higher in ex vivo cultures of fibrotic livers compared to controls (P<0.001). CONCLUSION: We have developed a novel ELISA for measuring a specific fragment CO3 generated by MMP-9 important in pathogenesis of liver fibrosis.


Asunto(s)
Colágeno Tipo III/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Epítopos/sangre , Cirrosis Hepática/sangre , Metaloproteinasa 9 de la Matriz/sangre , Modelos Biológicos , Adulto , Animales , Biomarcadores/sangre , Biomarcadores/metabolismo , Colágeno Tipo III/metabolismo , Epítopos/metabolismo , Matriz Extracelular , Femenino , Humanos , Cirrosis Hepática/metabolismo , Masculino , Metaloproteinasa 9 de la Matriz/metabolismo , Persona de Mediana Edad , Ratas , Ratas Sprague-Dawley , Valores de Referencia , Adulto Joven
15.
Rev Sci Instrum ; 80(2): 026102, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19256678

RESUMEN

Time-resolved measurement of population dynamics extending over femtosecond to millisecond time scales typically requires a combination of transient absorption techniques involving different laser systems and detection schemes. The spectrometer design presented here facilitates transient absorption measurements over 12 decades with a single ultrafast laser system by picking pump and probe pulses independently from the laser oscillator pulse train. Unamplified pulses seed a photonic crystal fiber to a supercontinuum probe source for spectrally resolved measurements. The utility of the system is demonstrated by measuring triplet state dynamics following photoexcitation of vitamin B(6) in aqueous solution.


Asunto(s)
Tecnología de Fibra Óptica/instrumentación , Rayos Láser , Iluminación/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Análisis Espectral/instrumentación , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
Scand J Med Sci Sports ; 19(5): 621-6, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18980605

RESUMEN

Overload tendon injuries are frequent in recreational and elite sports. The optimal treatment strategy remains unknown, but local administration of corticosteroids is one common treatment option. The direct effects of the corticosteroid administration on the tissue are not fully understood. The present study examined the biomechanical effects of intratendinous corticosteroid injections on healthy rat-tail tendon collagen fascicles. A total of 24 Wistar male rats were divided into (A) a corticosteroid group where the animals were injected in the tail tendon with methylprednisolone acetate, 1.0 mL of 40 mg/mL mixed with 1.0 mL 9% saline (n=12), and (B) a control group that was injected with 9% saline (n=12). Three days after the injections, the animals were sacrificed and single individual collagen fascicles were collected and underwent displacement to failure. Corticosteroid administration significantly reduced tensile fascicle yield strength by 16% and Young's modulus by 14% compared with sham treatment (10.5+/-0.8 vs 12.4+/-0.5 MPa, P< or =0.05, and 537+/-27 vs 641+/-30 MPa, P<0.05, respectively), while the strain properties were unaffected. Peak stress was similar between the two groups. There was no difference in fascicle diameter between the two groups.


Asunto(s)
Antiinflamatorios/metabolismo , Colágeno/efectos de los fármacos , Metilprednisolona/análogos & derivados , Cola (estructura animal)/fisiología , Tendones/efectos de los fármacos , Animales , Antiinflamatorios/administración & dosificación , Fenómenos Biomecánicos/efectos de los fármacos , Masculino , Metilprednisolona/administración & dosificación , Metilprednisolona/metabolismo , Acetato de Metilprednisolona , Ratas , Ratas Wistar , Resistencia a la Tracción/efectos de los fármacos
17.
J Biomed Mater Res A ; 89(1): 117-23, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18431764

RESUMEN

The inhibitor of p38 mitogen-activated protein kinase (MAPK) is of interest in the nonoperative treatment of periprosthetic osteolysis due to wear particles. Previous studies demonstrated that an oral p38 MAPK inhibitor did not suppress bone formation when given during the initial phase of tissue differentiation. However, the oral p38 MAPK inhibitor also did not curtail the foreign body and chronic inflammatory response to particles when given simultaneously. The purpose of the current study was to examine the efficacy of a p38 MAPK inhibitor, SCIO-323, on mitigating an established inflammatory reaction that parallels the clinical situation more closely. The Bone Harvest Chamber was implanted in rabbits and submicron polyethylene particles were placed in the chamber for 6 weeks. The contents of the chambers were harvested every 6 weeks. Oral treatment with the SCIO-323 included delivery for 3 weeks and stopping for 3 weeks, delivery for 3 weeks after an initial 3-week delay, and delivery for 6 weeks continuously. Administration of the SCIO-323 continuously for 6 weeks with/without the presence of particles, or for the initial 3 of 6 weeks had minor effects on bone ingrowth. After establishing a particle-induced chronic inflammatory reaction for 3 weeks, administration of SCIO-323 for a subsequent 3 weeks suppressed net bone formation. The activity of osteoclast-like cells remained low among all treatments when compared with the first control. Using the present model, the oral p38 MAPK inhibitor was ineffective in improving bone ingrowth in the presence of polyethylene particles.


Asunto(s)
Inhibidores Enzimáticos/uso terapéutico , Inflamación/tratamiento farmacológico , Polietileno/inmunología , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Animales , Materiales Biocompatibles/metabolismo , Huesos/citología , Huesos/efectos de los fármacos , Huesos/metabolismo , Humanos , Implantes Experimentales , Masculino , Ensayo de Materiales , Conejos
18.
Nurs Stand ; 21(48): 35-40, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17844825

RESUMEN

Healthcare delivery is associated with various risks and it is unlikely that these can ever be completely eliminated. Medicine management is an area known to involve errors. This article describes how implementing a systematic response to medication errors enables health professionals to identify individual and organisational failures and reduce adverse patient outcomes.


Asunto(s)
Errores de Medicación/prevención & control , Árboles de Decisión , Humanos , Seguridad , Medicina Estatal/organización & administración , Reino Unido
19.
J Wound Care ; 16(3): 118-21, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17385588

RESUMEN

OBJECTIVE: Fentanyl is a potent opioid that is well absorbed via the oral mucosa. It can be given as an oral lozenge. The onset of analgesia is rapid and matches the pain profile observed at dressing changes. METHOD: Patients experiencing pain during daily dressing changes were given entonox plus either placebo or oral transmucosal fentanyl citrate (OTFC) for two consecutive dressing changes in a randomised double-blind placebo-controlled crossover trial. RESULTS: Nine patients were recruited. The mean worst pain score during dressing changes was 7/10 with placebo and 4/10 with OTFC; the reduction in pain achieved with OTFC was significant. The mean number of breaths of entonox taken during the dressing change was 27.67 with placebo and 4.67 with OTFC; the reduction in the number of entonox breaths with OTFC was significant. One patient in the OTFC group suffered nausea. CONCLUSION: Compared with placebo, OTFC improved analgesia during painful dressing changes without an increase in side-effects.


Asunto(s)
Analgésicos Opioides/uso terapéutico , Vendajes/efectos adversos , Fentanilo/uso terapéutico , Dolor/tratamiento farmacológico , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos Opioides/metabolismo , Anestésicos Combinados/uso terapéutico , Estudios Cruzados , Método Doble Ciego , Quimioterapia Combinada , Femenino , Fentanilo/metabolismo , Semivida , Humanos , Masculino , Persona de Mediana Edad , Mucosa Bucal , Óxido Nitroso/uso terapéutico , Oxígeno/uso terapéutico , Dolor/diagnóstico , Dolor/etiología , Dolor/metabolismo , Dimensión del Dolor , Índice de Severidad de la Enfermedad , Cuidados de la Piel/efectos adversos , Factores de Tiempo , Resultado del Tratamiento
20.
J Biomed Mater Res A ; 79(3): 740-6, 2006 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-16988970

RESUMEN

Excessive polyethylene wear particles from joint replacements may lead to periprosthetic osteolysis and loosening. Nonsteroidal anti-inflammatory drugs (NSAIDs) decrease fracture healing and bone ingrowth. We hypothesized that continuous local infusion of OP-1 (BMP-7) would increase local bone formation in the presence of two different adverse stimuli, polyethylene particles, and an oral NSAID. The Drug Test Chamber (DTC) was implanted in the proximal tibia of mature rabbits. The tissue growing into the chamber was exposed to OP-1 solution (110 ng/day), which was infused via an osmotic pump. Infusion of OP-1 alone for 6 weeks enhanced local bone formation in the chamber by 80% (p < 0.05) over infusion of carrier alone. In the presence of polyethylene particles, infusion of OP-1 increased local bone formation by 38% (p < 0.05) over treatment with particles and carrier. Oral administration of NSAID reduced local bone formation by 58% (p < 0.05); this suppressive effect caused by NSAIDS was completely reversed by the infusion of OP-1 (p < 0.05). These findings underline a potential role for local treatment with OP-1 to increase bone formation in the presence of potentially adverse stimuli such as polyethylene wear particles or NSAID use.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Proteínas Morfogenéticas Óseas/farmacología , Osteogénesis/efectos de los fármacos , Factor de Crecimiento Transformador beta/farmacología , Fosfatasa Alcalina/metabolismo , Animales , Proteína Morfogenética Ósea 7 , Polietileno , Conejos
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