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Biological invasions are accelerating worldwide, causing major ecological and economic impacts in aquatic ecosystems. The urgent decision-making needs of invasive species managers can be better met by the integration of biodiversity big data with large-domain models and data-driven products. Remotely sensed data products can be combined with existing invasive species occurrence data via machine learning models to provide the proactive spatial risk analysis necessary for implementing coordinated and agile management paradigms across large scales. We present a workflow that generates rapid spatial risk assessments on aquatic invasive species using occurrence data, spatially explicit environmental data, and an ensemble approach to species distribution modeling using five machine learning algorithms. For proof of concept and validation, we tested this workflow using extensive spatial and temporal hybridization and occurrence data from a well-studied, ongoing, and climate-driven species invasion in the upper Flathead River system in northwestern Montana, USA. Rainbow Trout (RBT; Oncorhynchus mykiss), an introduced species in the Flathead River basin, compete and readily hybridize with native Westslope Cutthroat Trout (WCT; O. clarkii lewisii), and the spread of RBT individuals and their alleles has been tracked for decades. We used remotely sensed and other geospatial data as key environmental predictors for projecting resultant habitat suitability to geographic space. The ensemble modeling technique yielded high accuracy predictions relative to 30-fold cross-validated datasets (87% 30-fold cross-validated accuracy score). Both top predictors and model performance relative to these predictors matched current understanding of the drivers of RBT invasion and habitat suitability, indicating that temperature is a major factor influencing the spread of invasive RBT and hybridization with native WCT. The congruence between more time-consuming modeling approaches and our rapid machine-learning approach suggest that this workflow could be applied more broadly to provide data-driven management information for early detection of potential invaders.
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We report the spectral properties of 2-Phenylindole (2PI) embedded in rigid poly (vinyl alcohol) (PVA) film. The 2PI in PVA film shows relatively strong and structured fluorescence with a maximum at 370 nm and surprisingly strong room temperature phosphorescence with an emission maximum of about 500 nm. The dye is highly immobilized in the polymer matrix, thus presenting high fluorescence anisotropy in an isotropic film of about 0.3 at room temperature. The 2-Phenylindole phosphorescence excited in the usual way through the electronic singlet state excitation (S0 â S1 absorption) results in a very low, near zero anisotropy. We now report that we can directly excite the dye to the triplet state T1 and observe high phosphorescence anisotropy similar to the fluorescence anisotropy. The extinction coefficient for S0 â T1 absorption in the PVA matrix is unusually high- only about 3 orders of magnitude lower than S0 â S1 absorption. We consider this direct excitation to indole's triplet state a very significant finding that may lead to many practical applications. The unusually long-wavelength of excitation around 400 nm, much above typical UV absorption, results in a high phosphorescence anisotropy. This provides a new way to study rotational motion of larger biological objects in the microsecond time scale not accessible through typical fluorescence studies.
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Although BSA Au clusters fluoresce in red region (λmax: 650 nm), they are of limited use due to low fluorescence quantum yield (~6%). Here we report an enhanced fluorescence imaging application of fluorescent bio-nano probe BSA Au clusters using multipulse excitation scheme. Multipulse excitation takes advantage of long fluorescence lifetime (> 1 µs) of BSA Au clusters and enhances its fluorescence intensity 15 times over short lived cellular auto-fluorescence. Moreover we have also shown that by using time gated detection strategy signal (fluorescence of BSA Au clusters) to noise (auto-fluorescence) ratio can be increased by 30 fold. Thereby with multipulse excitation long lifetime probes can be used to develop biochemical assays and perform optical imaging with zero background.
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Colorantes Fluorescentes , Oro , Albúmina Sérica Bovina , Línea Celular Tumoral , Fluorescencia , Humanos , Nanoestructuras , Relación Señal-Ruido , Espectrometría de FluorescenciaRESUMEN
BACKGROUND: Transcranial magnetic stimulation (TMS) is a safe and effective treatment for major depression. We describe quality of life (QOL) outcomes from acute treatment with TMS, and describe the durability of benefit across 24-weeks. METHODS: Three hundred and one medication-free patients with pharmacoresistant major depression were randomized to active or sham TMS in a 6-week controlled trial. Nonresponders to the 6-week blinded phase of the study were enrolled in a 6-week open-label study without unblinding the prior treatment assignment. Responders and partial responders to both the blinded (active or sham treatment) or open acute treatment phases were tapered off TMS over three weeks, while initiating maintenance antidepressant medication monotherapy. These subjects entered the 24-week study to examine the durability of response to TMS. The Medical Outcomes Study-36 Item Short Form (SF-36) and the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q) were used to measure overall function and QOL. During the 24-week durability of effect study, QOL assessments were done at study entry and at the end of 24-weeks. RESULTS: Statistically significant improvement in both functional status and QOL outcomes was observed in patients treated with active TMS compared with sham TMS during the acute phase of the randomized, sham-controlled trial. Similar benefits were observed in patients who entered the open-label extension study. These improvements were sustained across the 24-week follow up study. CONCLUSIONS: Acute treatment with TMS improved functional status and QOL outcomes in patients with major depression. This clinical effect was durable in long-term follow up.
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Trastorno Depresivo Mayor/terapia , Trastorno Depresivo Resistente al Tratamiento/terapia , Calidad de Vida , Estimulación Magnética Transcraneal/métodos , Antidepresivos/uso terapéutico , Trastorno Depresivo Mayor/fisiopatología , Trastorno Depresivo Mayor/psicología , Trastorno Depresivo Resistente al Tratamiento/fisiopatología , Trastorno Depresivo Resistente al Tratamiento/psicología , Método Doble Ciego , Estudios de Seguimiento , Humanos , Satisfacción Personal , Retratamiento , Encuestas y Cuestionarios , Resultado del TratamientoRESUMEN
Molecules which are magnetic and conducting, if suitably entangled (e.g., catenanes and knots) could exhibit Aharonov-Bohm effects which can be viewed as particular examples of a Berry phase. The corrections to the quantum energy levels reflect the entangled geometry of the molecules and, while small (they are proportional to the square of the fine structure constant), may be observable. We illustrate these corrections for a number of catenated and knotted structures. For couplings between the components of a catenane (link), the Aharonov-Bohm corrections are determined by integer-valued linking numbers. For knots, the Aharonov-Bohm correction is proportional to the geometric writhe of the knot.
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The stratified epithelia of the oral cavity are continually exposed to bacterial challenge that is initially resisted by innate epithelial factors and by the recruitment of neutrophils. Antimicrobial peptides from phagocytes and epithelia contribute to this antimicrobial barrier. Using antibodies and in situ hybridization, we explored antimicrobial peptide expression in the varied epithelia of the periodontium and in cultured gingival epithelial cells. In gingival tissue, mRNA for the beta-defensins, human beta-defensin 1 (hBD-1) and human beta-defensin 2 (hBD-2) was predominately localized in suprabasal stratified epithelium and the peptides were detected in upper epithelial layers consistent with the formation of the stratified epithelial barrier. In cultured epithelial cells, both hBD-1 and -2 peptides were detected only in differentiating, involucrin-positive epithelial cells, although hBD-2 required stimulation by proinflammatory mediators or bacterial products for expression. Beta-defensins were not detected in junctional epithelium (JE) that serves as the attachment to the tooth surface. In contrast, alpha-defensins and cathelicidin family member LL-37 were detected in polymorphonuclear neutrophils (PMNs) that migrate through the JE, a localization that persists during inflammation, when the JE and surrounding tissue are highly infiltrated with PMNs. Thus, the undifferentiated JE contains exogenously expressed alpha-defensins and LL-37, and the stratified epithelium contains endogenously expressed beta-defensins. These findings show that defensins and other antimicrobial peptides are localized in specific sites in the gingiva, are synthesized in different cell types, and are likely to serve different roles in various regions of the periodontium.
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Antiinfecciosos Locales/metabolismo , Péptidos Catiónicos Antimicrobianos/biosíntesis , Inserción Epitelial/metabolismo , Encía/metabolismo , Adulto , Catelicidinas , Células Cultivadas , Defensinas/biosíntesis , Inserción Epitelial/citología , Células Epiteliales/metabolismo , Encía/citología , Humanos , Inmunohistoquímica , Hibridación in Situ , ARN Mensajero/análisisRESUMEN
BACKGROUND AND OBJECTIVE: Photothermal heating of mechanically deformed cartilage accelerates stress relaxation and results in sustained shape change. In this study, shape retention was measured in Nd:YAG laser reshaped porcine septal cartilage. MATERIALS AND METHODS: Specimens were laser reshaped either 4 (Group I) or 28 hours (Group II) following extraction from the crania. Specimens were bent into approximately semicircular shapes and irradiated half way between the endpoints of the semicircle. Resultant bend angle was calculated based on linear measurements. Shape retention was calculated by comparing resultant curvature with pre-irradiation measurements. RESULTS: Mechanical deformation alone resulted in initial bend angles varying from 188 degrees to 229 degrees. Resultant bend angles varied from 84 degrees to 194 degrees corresponding to shape retention varying from 58 to 75%. Non-irradiated cartilage retained less than 46% of the original bend. Shape retention was greater in Group II, compared to Group I. In Group I, no cephalocranial difference in shape retention was observed, though in Group II greater shape retention was observed in rostral specimens. CONCLUSION: While laser heating does significantly reshape cartilage, clinical use of this technology will require "overbending" of the cartilage graft to compensate for this memory effect. The degree of overbending is likely to vary with cartilage type and location.
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Rayos Láser , Tabique Nasal , Animales , Procedimientos de Cirugía Plástica , PorcinosRESUMEN
Human beta-defensins are antimicrobial peptides that may be critical in the innate immune response to infection. hBD1 and hBD2 are expressed in oral epithelial cells and are detected near the surface of oral tissue, consistent with a role in the epithelial protective barrier function. In this report, we examine secretion of beta-defensins in vitro and in biological fluid using ProteinChip(R) Array, surface enhanced laser desorption/ionization (SELDI) technology combined with time-of-flight mass spectrometry. We show that the 47-amino acid form of hBD1 and the 41-amino acid form of hBD2 are the major secreted forms. These forms are both expressed and secreted under conditions anticipated from previous analysis of beta-defensin mRNAs; specifically, hBD1 is detected in culture supernatant from both unstimulated and stimulated cells, and hBD2 is detected only in stimulated cells. Identity of hBD1 and hBD2 was confirmed by immunocapture on the ProteinChip surface. Both peptides are also present in gingival crevicular fluid that accumulates between the tissue and tooth surface, although hBD1 is also found in several smaller forms suggesting extracellular proteolysis. This methodology offers several technical advantages for detection of defensins in biological fluids, including ease and speed of screening, no need for HPLC preliminary processing, and small sample size.
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Células Epiteliales/inmunología , Encía/citología , Inmunoensayo/métodos , Espectrometría de Masas/métodos , beta-Defensinas/metabolismo , Células Cultivadas , Medios de Cultivo Condicionados , Células Epiteliales/metabolismo , Líquido del Surco Gingival/inmunología , Humanos , Sensibilidad y Especificidad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodosRESUMEN
The traditional hard-disk Lorentz gas describes the chaotic motion of a classical point particle through an array of impenetrable disks. Soft-disk modifications of the two-dimensional Lorentz gas, where the scattering particle can move into the disk interiors, are considered here. Conditions on the soft-disk potentials and disk separations that guarantee chaotic motion are obtained.
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Renal failure continues to carry substantial burden of morbidity and mortality in both acute and chronic forms, despite advances in transplantation and dialysis. There is evidence to suggest that the kidney has metabolic, endocrine, and immune effects transcending its filtration functions, even beyond secretion of renin and erythropoietin. Our laboratory has developed experience in the tissue culture of renal parenchymal cells, and has now been able to demonstrate the metabolic activity of these cells in an extracorporeal circuit recapitulating glomerulotubular anatomy. We have observed active transport of sodium, glucose, and glutathione. We describe the design and initial preclinical testing of the bioartificial kidney, as well as future directions of our research.
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Órganos Bioartificiales , Riñones Artificiales , Insuficiencia Renal/terapia , Animales , Reactores Biológicos , Células Cultivadas , Eritropoyetina/metabolismo , Túbulos Renales Proximales/citología , Renina/metabolismoRESUMEN
The oral cavity is exposed to a variety of environmental insults. Salivary secretions play a critical role in maintaining oral health via innate host defense mechanisms and secretion of secretory IgA. Human beta-defensins (hBD) are antimicrobial peptides that are a component of the innate immune response; they are expressed in epithelia and are proposed to have a role in mucosal defense. hBD-1 mRNA is constitutively expressed in numerous mucosal tissues, including human gingiva and submandibular and parotid glands. Our objective was to detect the expression and localization of hBD-1 peptide in human salivary glands and in saliva. Minor salivary gland tissue was obtained from biopsies of patients with mucoceles (n = 20). hBD-1 peptide was detected by immunohistochemistry; expression was localized to the ductal cells and not the acinar cells of these glands. The peptide was located apically, toward the lumen in the duct cells. Further evaluation showed stronger hBD-1 expression in ducts with periductal inflammation, as indicated by the immunostaining of serial sections with anti-CD45 specific for B- and T-lymphocytes. Statistical analysis showed a strong correlation of hBD-1 staining and inflammation. Results of immunolocalization suggest that hBD-1 functions to protect salivary glands from retrograde infection, that expression of the peptide is enhanced in inflamed sites, and that post-transcriptional regulatory mechanisms may be involved in hBD-1 peptide expression. Western immunoblot analysis also detected hBD-1 peptide in unstimulated, whole, acidified saliva from normal volunteers. However, hBD-1 peptide associated with salivary mucin resulted in loss of the detection in a dot-immunoblot assay. Association of hBD-1 with salivary mucin may facilitate peptide distribution and adherence to oral surfaces and aid its function within the oral cavity.
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Regulación de la Expresión Génica/fisiología , Proteínas/metabolismo , Saliva/metabolismo , Conductos Salivales/metabolismo , Glándulas Salivales Menores/metabolismo , beta-Defensinas , Adulto , Biopsia , Western Blotting/métodos , Defensinas , Humanos , Immunoblotting/métodos , Inmunohistoquímica , Mucocele/metabolismo , Mucocele/patología , Proteínas/análisis , Saliva/química , Conductos Salivales/química , Conductos Salivales/patología , Enfermedades de las Glándulas Salivales/metabolismo , Enfermedades de las Glándulas Salivales/patología , Glándulas Salivales Menores/química , Glándulas Salivales Menores/patología , Sialadenitis/metabolismo , Sialadenitis/patologíaRESUMEN
Human gingival epithelial cells (HGE) express two antimicrobial peptides of the beta-defensin family, human beta-defensin 1 (hBD-1) and hBD-2, as well as cytokines and chemokines that contribute to innate immunity. In the present study, the expression and transcriptional regulation of hBD-2 was examined. HBD-2 mRNA was induced by cell wall extract of Fusobacterium nucleatum, an oral commensal microorganism, but not by that of Porphyromonas gingivalis, a periodontal pathogen. HBD-2 mRNA was also induced by the proinflammatory cytokine tumor necrosis factor alpha (TNF-alpha) and phorbol myristate acetate (PMA), an epithelial cell activator. HBD-2 mRNA was also expressed in 14 of 15 noninflamed gingival tissue samples. HBD-2 peptide was detected by immunofluorescence in HGE stimulated with F. nucleatum cell wall, consistent with induction of the mRNA by this stimulant. Kinetic analysis indicates involvement of multiple distinct signaling pathways in the regulation of hBD-2 mRNA; TNF-alpha and F. nucleatum cell wall induced hBD-2 mRNA rapidly (2 to 4 h), while PMA stimulation was slower ( approximately 10 h). In contrast, each stimulant induced interleukin 8 (IL-8) within 1 h. The role of TNF-alpha as an intermediary in F. nucleatum signaling was ruled out by addition of anti-TNF-alpha that did not inhibit hBD-2 induction. However, inhibitor studies show that F. nucleatum stimulation of hBD-2 mRNA requires both new gene transcription and new protein synthesis. Bacterial lipopolysaccharides isolated from Escherichia coli and F. nucleatum were poor stimulants of hBD-2, although they up-regulated IL-8 mRNA. Collectively, our findings show inducible expression of hBD-2 mRNA via multiple pathways in HGE in a pattern that is distinct from that of IL-8 expression. We suggest that different aspects of innate immune responses are differentially regulated and that commensal organisms have a role in stimulating mucosal epithelial cells in maintaining the barrier that contributes to homeostasis and host defense.
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Fusobacterium nucleatum/inmunología , Regulación de la Expresión Génica , Proteínas/genética , Transducción de Señal , beta-Defensinas , Adolescente , Adulto , Células Cultivadas , Cicloheximida/farmacología , Dactinomicina/farmacología , Defensinas , Células Epiteliales/efectos de los fármacos , Células Epiteliales/inmunología , Técnica del Anticuerpo Fluorescente Indirecta , Regulación de la Expresión Génica/efectos de los fármacos , Encía/citología , Encía/inmunología , Encía/patología , Humanos , Cinética , Lipopolisacáridos/inmunología , Lipopolisacáridos/farmacología , Mitógenos/inmunología , Mitógenos/farmacología , Inhibidores de la Síntesis del Ácido Nucleico/farmacología , Péptidos/metabolismo , Porphyromonas gingivalis/inmunología , Inhibidores de la Síntesis de la Proteína/farmacología , Proteínas/metabolismo , ARN Mensajero , Acetato de Tetradecanoilforbol/inmunología , Acetato de Tetradecanoilforbol/farmacología , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/farmacología , Regulación hacia ArribaRESUMEN
The large magnitude of predicted warming at high latitudes and the potential feedback of ecosystems to atmospheric CO2 concentrations make it important to quantify both warming and its effects on high-latitude carbon balance. We analysed long-term, daily surface meteorological records for 13 sites in Alaska and north-western Canada and an 82-y record of river ice breakup date for the Tanana River in interior Alaska. We found increases in winter and spring temperature extrema for all sites, with the greatest increases in spring minimum temperature, average 0.47 °C per 10 y, and a 0.7-day per 10 y advance in ice breakup on the Tanana River. We used the climate records to drive an ecosystem process model, BIOME_BGC, to simulate the effects of climate change on the carbon and water balances of boreal forest ecosystems. The growing season has lengthened by an average of 2.6 days per 10 y with an advance in average leaf onset date of 1.10 days per 10 y. This advance in the start of the active growing season correlates positively with progressively earlier ice breakup on the Tanana River in interior Alaska. The advance in the start of the growing season resulted in a 20% increase in net primary production for both aspen (Populus tremuloides) and white spruce (Picea glauca) stands. Aspen had a greater mean increase in maintenance respiration than spruce, whereas spruce had a greater mean increase in evapotranspiration. Average decomposition rates also increased for both species. Both net primary production and decomposition are enhanced in our simulations, suggesting that productive forest types may not experience a significant shift in net carbon flux as a result of climate warming.
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An ecological process model (BIOME-BGC) was used to assess boreal forest regional net primary production (NPP) and response to short-term, year-to-year weather fluctuations based on spatially explicit, land cover and biomass maps derived by radar remote sensing, as well as soil, terrain and daily weather information. Simulations were conducted at a 30-m spatial resolution, over a 1205 km(2) portion of the BOREAS Southern Study Area of central Saskatchewan, Canada, over a 3-year period (1994-1996). Simulations of NPP for the study region were spatially and temporally complex, averaging 2.2 (+/- 0.6), 1.8 (+/- 0.5) and 1.7 (+/- 0.5) Mg C ha(-1) year(-1) for 1994, 1995 and 1996, respectively. Spatial variability of NPP was strongly controlled by the amount of aboveground biomass, particularly photosynthetic leaf area, whereas biophysical differences between broadleaf deciduous and evergreen coniferous vegetation were of secondary importance. Simulations of NPP were strongly sensitive to year-to-year variations in seasonal weather patterns, which influenced the timing of spring thaw and deciduous bud-burst. Reductions in annual NPP of approximately 17 and 22% for 1995 and 1996, respectively, were attributed to 3- and 5-week delays in spring thaw relative to 1994. Boreal forest stands with greater proportions of deciduous vegetation were more sensitive to the timing of spring thaw than evergreen coniferous stands. Similar relationships were found by comparing simulated snow depth records with 10-year records of aboveground NPP measurements obtained from biomass harvest plots within the BOREAS region. These results highlight the importance of sub-grid scale land cover complexity in controlling boreal forest regional productivity, the dynamic response of the biome to short-term interannual climate variations, and the potential implications of climate change and other large-scale disturbances.
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The present study examined the cases of 353 patients seen in the outpatient department of psychiatry at a large west coast HMO. Comparisons were made between self-referred and physician-referred patients in the types of problems presented for treatment. Patients with relationship problems were self-referred more than those with adjustment, anxiety, and mood disorders who were more likely to be physician-referred. HMO patients with a self-referral option appear to enter mental health treatment because of relationship problems at a higher rate than their physician-referred counterparts.
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Sistemas Prepagos de Salud/estadística & datos numéricos , Servicios de Salud Mental/estadística & datos numéricos , Derivación y Consulta/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Modelos Logísticos , Masculino , Trastornos Mentales/clasificación , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Estados UnidosRESUMEN
Profilaggrin is a large phosphoprotein that is expressed in the granular cells of epidermis where it is localized in keratohyalin. It consists of multiple copies of single filaggrin units plus N- and C-terminal sequences that differ from filaggrin. Profilaggrin is dephosphorylated and proteolytically processed during terminal differentiation to yield filaggrin, which associates with keratin intermediate filaments to form macrofibrils in the lower layers of the stratum corneum. The N-terminal sequence of human profilaggrin comprises two distinct domains; an acidic A domain of 81 amino acids that binds Ca2+, and a cationic B domain of 212 residues. In this report, we further characterize the N-terminal domain by immunohistochemistry and immunoblot analysis using anti-peptide antibodies raised to the A and B regions. All of these antibodies (n = 4) immunostained keratohyalin in the granular layer of human epidermis and also showed some reaction with the lower stratum corneum. In immunoblot studies, the high molecular weight human profilaggrin reacted with both B domain antibodies whereas it showed a weak and variable reaction with A domain antibodies. In addition to profilaggrin, a cationic 32-kDa protein was detected with all N-terminal antibodies. A similar-sized N-terminal peptide was also produced by in vitro proteolysis of human profilaggrin with endoproteinase 1 (PEP1), a protease involved in processing of mouse profilaggrin, and in cultured rat epidermal keratinocytes transfected with a human profilaggrin cDNA construct. Evidence for at least one additional cleavage within the N-terminal domain is shown by immunoreactivity of smaller (16-20 kDa) acidic and basic proteins with A and B domain antibodies, respectively. These results demonstrate that the N-terminal domain is an integral part of profilaggrin in keratohyalin but is proteolytically cleaved from profilaggrin during the terminal differentiation of keratinocytes to yield a 32-kDa peptide.
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Células Epidérmicas , Proteínas de Filamentos Intermediarios/química , Precursores de Proteínas/química , Secuencia de Aminoácidos , Diferenciación Celular , Células Cultivadas , ADN Complementario/análisis , Endopeptidasas/metabolismo , Proteínas Filagrina , Expresión Génica , Humanos , Immunoblotting , Inmunohistoquímica , Proteínas de Filamentos Intermediarios/genética , Queratinocitos/citología , Datos de Secuencia Molecular , Mucosa Bucal/citología , Péptidos/metabolismo , Precursores de Proteínas/genética , Estructura Terciaria de ProteínaRESUMEN
Since several lines of evidence implicate the 3'-flanking region in regulating alpha1(I) collagen gene transcription, we analyzed 12. 4-kilobase pairs of 3'-flanking sequence of the murine alpha1(I) collagen gene for transcriptional elements. A region of the 3'-flanking region stimulated expression of the heterologous beta-globin gene promoter in an enhancer trap plasmid and of the alpha1(I) collagen gene promoter in a collagen-luciferase reporter gene construct when located 3' to the luciferase reporter gene. DNase I footprinting analysis demonstrated the presence of three regions where DNA binding proteins specifically interact within this 3'-stimulatory region. Inspection of the DNA sequence revealed a consensus E-box, a binding site for basic helix-loop-helix proteins, in one of the protein binding sites. Mobility shift assays demonstrated that upstream stimulatory factors (USF) USF-1 and USF-2 bind to this E-box. Mutating the E-box in the context of the 3'-flanking region confirmed that it contributes to the enhancement of transcriptional activity of the alpha1(I) collagen gene promoter. Mutations in all three protein binding sites abolished transcriptional activation by the 3'-flanking region, suggesting a complex interaction among the trans-acting factors in enhancing transcriptional activity. Thus, a region of the 3'-flanking region of the alpha1(I) collagen gene stimulates transcription of the alpha1(I) collagen gene promoter, and USF-1 and USF-2 contribute to this transcriptional stimulation.
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Colágeno/genética , Factores de Transcripción/metabolismo , Transcripción Genética , Células 3T3 , Animales , Secuencia de Bases , Colágeno/metabolismo , ADN , Proteínas de Unión al ADN/metabolismo , Elementos de Facilitación Genéticos , Regulación de la Expresión Génica , Ratones , Datos de Secuencia Molecular , Plásmidos , Regiones Promotoras Genéticas , Unión Proteica , Factores Estimuladores hacia 5'RESUMEN
Tepoxalin [5- (4-chlorophenyl)-N-hydroxy-1-(4-methoxyphenyl)-N-methyl-1H-pyrazole -3-propanamide] is an orally active anti-inflammatory agent, which inhibits both cyclooxygenase and 5-lipoxygenase activities. The oral toxicity of tepoxalin was evaluated in 1- and 6-month rat (up to 50 mg/kg/day) and dog (up to 150 mg/kg bid) studies. In rats, increased liver weight, centrilobular hypertrophy, and hepatic necrosis were observed at dosages >/=20 mg/kg/day. Renal changes indicative of analgesic nephropathy syndrome (i.e., papillary edema or necrosis, cortical tubular dilatation) were seen at >/=15 mg/kg. In rats treated for 1 month, these hepatic and renal effects were largely reversible after a 1-month recovery period. Gastrointestinal erosions and ulcers were seen in female rats given 40 mg/kg/day for 6 months. Changes in clinical pathology parameters included decreases in red blood cell count, hemoglobin, and hematocrit mean values; elevation in platelet counts; and an increase in prothrombin and activated partial thromboplastin times. Mild increases in alanine aminotransferase, aspartate aminotransferase, and cholesterol were also noted in rats. Decreased erythrocyte parameters, increased leukocyte counts, and decreased total protein, albumin, and/or calcium were noted in some dogs in the 300 mg/kg/day group following 6 months of dosing. Small pyloric ulcerations were seen at 100 and 300 mg/kg/day dosages for up to 6 months. In both rats and dogs, no accumulation of tepoxalin or its carboxylic acid metabolite was detected in plasma following multiple dosing over a range of 5 to 50 mg/kg/day for rats and 20 to 300 mg/kg/day for dogs. Plasma concentrations of the carboxylic acid metabolite were severalfold higher than those of the parent compound. The no-effect dosages in rats (5 mg/kg/day) and dogs (20 mg/kg/day) were approximately one and six times the ED50 (3.5 mg/kg), respectively, for inhibition of inflammatory effects in the adjuvant arthritic rat without gastric mucosal damage. In terms of severity, the relative lack of gastrointestinal side effects, within the estimated therapeutic dose range, distinguishes tepoxalin from most marketed anti-inflammatory drugs.
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Antiinflamatorios no Esteroideos/toxicidad , Pirazoles/toxicidad , Absorción , Administración Oral , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/farmacocinética , Enfermedad Hepática Inducida por Sustancias y Drogas , Química Clínica , Inhibidores de la Ciclooxigenasa , Perros , Femenino , Pruebas Hematológicas , Enfermedades Renales/inducido químicamente , Inhibidores de la Lipooxigenasa , Masculino , Tamaño de los Órganos/efectos de los fármacos , Pirazoles/administración & dosificación , Pirazoles/farmacocinética , Ratas , Ratas Sprague-Dawley , Tasa de SupervivenciaRESUMEN
Ten scientific organizations formed a joint international committee to provide expert recommendations for clinical pathology testing of laboratory animal species used in regulated toxicity and safety studies. For repeated-dose studies in rodent species, clinical pathology testing is necessary at study termination. Interim study testing may not be necessary in long-duration studies provided that it has been done in short-duration studies using dose levels not substantially lower than those used in the long-duration studies. For repeated-dose studies in nonrodent species, clinical pathology testing is recommended at study termination and at least once at an earlier interval. For studies of 2 to 6 weeks in duration in nonrodent species, testing is also recommended within 7 days of initiation of dosing, unless it compromises the health of the animals. If a study contains recovery groups, clinical pathology testing at study termination is recommended. The core hematology tests recommended are total leukocyte (white blood cell) count, absolute differential leukocyte count, erythrocyte (red blood cell) count, evaluation of red blood cell morphology, platelet (thrombocyte) count, hemoglobin concentration, hematocrit (or packed cell volume), mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration. In the absence of automated reticulocyte counting capabilities, blood smears from each animal should be prepared for reticulocyte counts. Bone marrow cytology slides should be prepared from each animal at termination. Prothrombin time and activated partial thromboplastin time (or appropriate alternatives) and platelet count are the minimum recommended laboratory tests of hemostasis. The core clinical chemistry tests recommended are glucose, urea nitrogen, creatinine, total protein, albumin, calculated globulin, calcium, sodium, potassium, total cholesterol, and appropriate hepatocellular and hepatobiliary tests. For hepatocellular evaluation, measurement of a minimum of two scientifically appropriate blood tests is recommended, e.g., alanine aminotransferase, aspartate aminotransferase, sorbitol dehydrogenase, glutamate dehydrogenase, or total bile acids. For hepatobiliary evaluation, measurement of a minimum of two scientifically appropriate blood tests is recommended, e.g., alkaline phosphatase, gamma glutamyltransferase, 5' -nucleotidase, total bilirubin, or total bile acids. Urinalysis should be conducted at least once during a study. For routine urinalysis, an overnight collection (approximately 16 hr) is recommended. It is recommended that the core tests should include an assessment of urine appearance (color and turbidity), volume, specific gravity or osmolality, pH, and either the quantitative or semiquantitative determination of total protein and glucose. For carcinogenicity studies, only blood smears should be made from unscheduled sacrifices (decedents) and at study termination to aid in the identification and differentiation of hematopoietic neoplasia.