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The concept of reaction extent (the progress of a reaction, advancement of the reaction, conversion, etc.) was introduced around 100 years ago. Most of the literature provides a definition for the exceptional case of a single reaction step or gives an implicit definition that cannot be made explicit. There are views that the reaction extent somehow has to tend to 1 when the reaction goes to completion as time tends to infinity. However, there is no agreement on which function should tend to 1. Starting from the standard definition by IUPAC and following the classical works by De Donder, Aris, and Croce, we extend the definition of the reaction extent for an arbitrary number of species and reaction steps. The new general, explicit definition is also valid for non-mass action kinetics. We also studied the mathematical properties (evolution equation, continuity, monotony, differentiability, etc.) of the defined quantity, connecting them to the formalism of modern reaction kinetics. Our approach tries to adhere to the customs of chemists and be mathematically correct simultaneously. To make the exposition easy to understand, we use simple chemical examples and many figures, throughout. We also show how to apply this concept to exotic reactions: reactions with more than one stationary state, oscillatory reactions, and reactions showing chaotic behavior. The main advantage of the new definition of reaction extent is that by knowing the kinetic model of a reacting system one can now calculate not only the time evolution of the concentration of each reacting species but also the number of occurrences of the individual reaction events.
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BACKGROUND AND AIMS: Relapse rates after discontinuing anti-tumor necrosis factor-α (TNFα) therapy of inflammatory bowel disease (IBD) patients in deep remission are poorly understood. This prospective single-center open-label study evaluated the relapse rates of IBD patients after stopping anti-TNFα therapy. METHODS: All IBD patients who were in clinical remission and stopped anti-TNFα therapy in 2011-2013 and were followed up for at least 12 months were enrolled. The "Ultradeep" patients were in calprotectin-negative (<50 ng/g) deep remission for at least six months and ceased anti-TNFα therapy on physician recommendations. The "clinical" patients were in clinical but not deep remission and ceased anti-TNFα therapy for other reasons. Relapse rates were assessed and relapse risk factors identified. RESULTS: One year after stopping, 27 % and 27 % of the Ultradeep (n = 11) and Clinical (n = 11) patients relapsed, respectively. Two years after stopping, 57 % and 62 % relapsed, respectively (p = 0.89). All relapsed patients who underwent retreatment with anti-TNFα therapy re-entered remission. Male sex was a significant risk factor for relapse (p = 0.03). CONCLUSION: Our study showed that even highly selected IBD patients who lack clinical, endoscopic or laboratory signs of disease activity have a relatively high relapse rate in the follow-up period after ceasing anti-TNFα therapy (Tab. 2, Fig. 3, Ref. 24).
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Colite Ulcerativa , Doença de Crohn , Adulto , Idoso , Colite Ulcerativa/sangue , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , Colite Ulcerativa/fisiopatologia , Doença de Crohn/sangue , Doença de Crohn/tratamento farmacológico , Doença de Crohn/patologia , Doença de Crohn/fisiopatologia , Feminino , Seguimentos , Fármacos Gastrointestinais/administração & dosagem , Fármacos Gastrointestinais/efeitos adversos , Humanos , Infliximab/administração & dosagem , Infliximab/efeitos adversos , Complexo Antígeno L1 Leucocitário/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Medição de Risco , Fatores de Risco , Fatores de Tempo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Suspensão de Tratamento/estatística & dados numéricosRESUMO
INTRODUCTION: Advanced diagnostic bronchoscopy includes endobronchial ultrasound (EBUS) guided transbronchial lung and lymph node biopsies, CT navigation and robotic bronchoscopy. Interventional bronchoscopy refers to procedures performed for therapeutic purposes such as balloon dilation of the airway, tissue debulking, cryotherapy, removal of foreign bodies and insertion of endobronchial valves [1]. For adult patients, these procedures are standard of care [2, 3]. Despite a lack of formalized training, there are numerous case reports and case series describing the use of advanced diagnostic and interventional bronchoscopy techniques in children. The safety and feasibility of EBUS-TBNA, cryotherapy techniques, endobronchial valves among other techniques have been demonstrated in these publications [1, 4-9]. METHODS: We sought to better understand the current practices and perspectives on interventional and advanced bronchoscopy among pediatric pulmonologists through surveys sent to pediatric teaching hospitals across the United States. RESULTS: We received 43 responses representing 28 programs from 25 states. The highest bronchoscopy procedure volume occurred in the 0-5 years age group. Among our respondents, 31% self-identified as a pediatric interventional/advanced bronchoscopist. 79% believe that advanced and interventional training is feasible in pediatric pulmonology and 77% believe it should be offered to pediatric pulmonary fellows. DISCUSSION: This is the first study to characterize current practices and perspectives regarding advanced diagnostic and interventional bronchoscopy procedures among pediatric pulmonologists in the United States. Pediatric interventional pulmonology (IP) is in its infancy and its beginnings echo those of the adult IP where only certain centers were performing these procedures.
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Broncoscopia , Pediatria , Pneumologistas , Broncoscopia/métodos , Broncoscopia/estatística & dados numéricos , Humanos , Estados Unidos , Pneumologistas/estatística & dados numéricos , Criança , Pediatria/educação , Inquéritos e Questionários , Pneumologia/educação , Padrões de Prática Médica/estatística & dados numéricos , Lactente , Pré-Escolar , Recém-NascidoRESUMO
Low serotonin(1A) receptor (5-HT(1A)R) binding is a risk factor for anxiety and depression, and deletion of the 5-HT(1A)R results in anxiety-like behavior in mice. Here we show that anxiety-like behavior in mice also can be caused, independently of the offspring's own 5-HT(1A)R genotype, by a receptor deficit in the mother: a nongenetic transmission of a genetic defect. Some of the nongenetically transmitted anxiety manifestations were acquired prenatally and linked to a delay in dentate gyrus maturation in the ventral hippocampus of the offspring. Both the developmental delay and the anxiety-like phenotype were phenocopied by the genetic inactivation of p16(ink4a) encoding a cyclin-dependent kinase inhibitor implicated in neuronal precursor differentiation. No maternal 5-HT(1A)R genotype-dependent anxiety developed when the strain background was switched from Swiss Webster to C57BL/6, consistent with the increased resilience of this strain to early adverse environment. Instead, all anxiety manifestations were caused by the offspring's own receptor deficiency, indicating that the genetic and nongenetic effects converge to common anxiety manifestations. We propose that 5-HT(1A)R deficit represents a dual risk for anxiety and that vulnerability to anxiety associated with genetic 5-HT(1A)R deficiency can be transmitted by both genetic and nongenetic mechanisms in a population. Thus, the overall effect of risk alleles can be higher than estimated by traditional genetic assays and may contribute to the relatively high heritability of anxiety and psychiatric disorders in general.
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Ansiedade/genética , Prenhez , Receptor 5-HT1A de Serotonina/genética , Receptor 5-HT1A de Serotonina/fisiologia , Animais , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Giro Denteado/metabolismo , Feminino , Genótipo , Exposição Materna , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Fenótipo , Gravidez , RiscoRESUMO
A survey was conducted on 13 dairies to determine the occurrence of 5 animal-borne pathogens (Salmonella enterica, Escherichia coli O157:H7, Campylobacter jejuni, Mycobacterium avium ssp. paratuberculosis, and Cryptosporidium parvum) and their distributions across farm elements (feces, bedding, milk filters, stored manure, field soil, and stream water). Presence of C. parvum was measured only in feces and stored manure. All but one farm were positive for at least one pathogen species, and 5 farms were positive for 3 species. Escherichia coli O157:H7 was detected on 6 farms and in all farm elements, including milk filters. Mycobacterium avium ssp. paratuberculosis was detected on 10 of 13 farms and in all farm elements except for milk filters. Salmonella enterica and C. jejuni were detected at lower frequencies and were not identified in soil, stream water, or milk filters on any of the 13 farms. Cryptosporidium parvum was detected in feces but not in stored manure. Stored manure had the highest occurrence of pathogens (73%), followed by feces (50%), milk filters, bedding, soil, and water (range from 23 to 31%). Association of pathogen presence with farm management factors was examined by t-test; however, the small number of study farms and samples may limit the scope of inference of the associations. Pathogens had a higher prevalence in maternity pen bedding than in calf bedding, but total pathogen occurrence did not differ in calf compared with lactating cow feces or in soils with or without manure incorporation. Herd size and animal density did not appear to have a consistent effect on pathogen occurrence. The extent of pathogen prevalence and distribution on the farms indicates considerable public health risks associated with not only milk and meat consumption and direct animal contact, but also potential dissemination of the pathogens into the agroecosystem.
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Doenças dos Bovinos/microbiologia , Indústria de Laticínios/estatística & dados numéricos , Animais , Campylobacter jejuni , Bovinos , Cryptosporidium parvum , Reservatórios de Doenças/microbiologia , Meio Ambiente , Escherichia coli O157 , Fezes/microbiologia , Esterco/microbiologia , Mycobacterium avium subsp. paratuberculosis , Salmonella enterica , Microbiologia do Solo , Microbiologia da ÁguaRESUMO
Basal cell carcinoma is the most common malignant tumor of the periocular region with local aggressive growth and extensive destruction. The histological subtypes of periocular basalioma, the recurrence rates and resection border relationships were analyzed and the results were compared with basaliomas from other body regions. The results of gender and age distribution, histological subtypes, recurrence rates and resection border relationships were evaluated using the χ(2)-test. The results showed a significantly higher recurrence rate (p < 0.01) for the periocular region compared to other body regions and the incidence of periocular basalioma was higher in women (p < 0.05). In addition the rarer histological subtypes were more commonly found in this region compared to other body regions (p < 0.01).
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Carcinoma Basocelular/patologia , Doenças Palpebrais/patologia , Neoplasias Cutâneas/patologia , Carcinoma Basocelular/diagnóstico , Carcinoma Basocelular/genética , Carcinoma Basocelular/cirurgia , Diagnóstico Diferencial , Progressão da Doença , Doenças Palpebrais/diagnóstico , Doenças Palpebrais/genética , Doenças Palpebrais/cirurgia , Regulação Neoplásica da Expressão Gênica/genética , Marcadores Genéticos/genética , Humanos , Invasividade Neoplásica , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Neoplasias Primárias Múltiplas/diagnóstico , Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/cirurgia , Prognóstico , Pele/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/cirurgiaRESUMO
AIM: Osteoporosis is a known chronic complication of inflammatory bowel diseases (IBD). The aim of our study was to describe the prevalence of reduced bone mineral density (BMD) in IBD patients and to identify crucial risk factors for osteoporosis. METHODS: The cohort consisted of 76 IBD patients, 40 with Crohn's disease (CD) and 36 with ulcerative colitis (UC). Clinical characteristics of every patient were recorded, i.e. age, sex, duration of the disease, clinical behavior, location of disease according to Montreal classification, surgeries, steroid medication, sIBDQ, and smoking habits. We examined the serum 25-hydroxyl vitamin D3 (25-OHD3) in each patient. The BMD was determined by dual-energy X-ray absorptiometry (DXA) at the lumbar spine and femoral neck. RESULTS: Osteoporosis was documented in 10 IBD patients (13.2 %), while osteopenia in 35 of them (46.1 %). Patients with CD have significantly lower femoral Z score than patients with UC. Femoral Z score was strongly associated with disease duration, and in CD patients suffering from stricturing form, with ileic or ileocolic location and history of proctocolectomy or total colectomy. Patients with osteoporosis had a significantly lower level of 25-OHD3 than patients with normal BMD. CONCLUSION: Patients with long disease duration and those suffering from stricturing form of CD with ileic/ileocolic location and history of proctocolectomy/total colectomy are at higher risk of developing osteoporosis than other IBD patients. The high proportion of osteopenia/osteoporosis in our study underlines the importance of BMD measurement in all IBD patients as a base for initiating the appropriate treatment (Tab. 1, Fig. 3, Ref. 63).
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Doenças Inflamatórias Intestinais/complicações , Osteoporose/epidemiologia , Osteoporose/etiologia , Adulto , Idoso , Densidade Óssea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Adulto JovemRESUMO
BACKGROUND AND AIMS: The thiopurine drugs, azathioprine (AZA) and 6-mercaptopurine, are established in the treatment of inflammatory bowel diseases (IBD). Polymorphisms in thiopurine S-methyltransferase (TPMT) gene have been associated with adverse drug reactions (ADRs) to AZA. METHODS: The aim of this study was to evaluate TPMT polymorphisms and AZA-related toxicity in a Slovak cohort of 220 IBD patients treated with AZA. In every patient, the dose and duration of AZA therapy, concomitant 5-aminosalicylate (5-ASA) medication, frequency, type, time to onset, dose of ADR and concomitant 5-ASA at the onset of ADR were recorded. Each patient was also genotyped for the presence of variant TPMT alleles (*2,*3A,*3B,*3C). Frequency, type and circumstances of ADRs were compared according to TPMT status. RESULTS: Of the 220 patients, 205 (93.2 %) were wild-type (TPMT*1/*1), one (0.5%) carried a TPMT*1/*3C allele, 13 (5.9 %) carried TPMT *1/*3A allele and one was homozygous for TMPT *3A allele. No TPMT *2 mutation was found. The incidence of adverse drug reactions was 62/205 (30.2 %) in the wild-type group as compared to 13/15 (86.7 %) in the TPMT mutation group, p=2.10-5. Leukopenia (WBC< 3.0*10^9/L) occurred in 21/205 (10.2 %) patients with wild type TPMT versus 11/15 (73.3 %) patients with TPMT mutations, p=0.000001. There was no significant difference between TMPT groups in gastrointestinal or other ADRs. No impact of 5-ASA on the incidence and severity of AZA adverse drug reactions was observed. CONCLUSION: The incidence of leukopenia in TPMT mutant patients was significantly higher and more severe as compared to TPMT wild type patients. We observed no impact of concomitant 5-ASA therapy on AZA induced toxicity (Tab. 4, Fig. 2, Ref. 37).
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Azatioprina/efeitos adversos , Imunossupressores/efeitos adversos , Doenças Inflamatórias Intestinais/genética , Metiltransferases/genética , Polimorfismo Genético , Adulto , Azatioprina/uso terapêutico , Feminino , Genótipo , Humanos , Imunossupressores/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Masculino , FarmacogenéticaRESUMO
INTRODUCTION: A comparison of the costs of a surgery and an endovascular treatment of abdominal aortic aneurysms (AAA) for the General Health Insurance Company (VsZP) in 2009-2010. MATERIAL AND METHODS: Between 2009 and 2010, VsZP paid for treatment of 211 patients with AAA with an average age of 69 years (range: 41-91 years). Out of these, 174 patients underwent surgical treatment and 37 patients were treated by endovascular means. In both groups, we observed a total cost of treatment, payment for hospitalization (UH) and separately charged material (ZM), the cost of blood and reimbursement for CT (computer tomography) examinations and the patient age. For statistical comparison, we used the nonparametric Mann-Whitney U test, the limit of statistical significance was <0.01. The data were processed and compared by means of contingency tables in MS Excel and then statistically processed in the program StatSoft, Inc.. (2011). STATISTICA (data analysis software system), version 10th www.statsoft.com. RESULTS: The total two-year costs of VsZP for the treatment of AAA were 1 212 188 - out of which 37% were represented by the OR costs (open repair) and 63% for EVAR (endovascular aneurysm repair) (p <0.01). In terms of the ZM use (p <0.01), and the use of CT examinations (p <0.01), EVAR is cost demanding. OR is cost demanding in terms of the blood consumption levels (p <0.01). The average total cost per admission was 21,038 for EVAR and 2,493 for OR, representing only 12% of the total EVAR costs. The age of patients has no impact on the costs (p> 0.01). The decisive impact on the total costs is represented by ZM, which presents 90 % of costs of EVAR method and 44% of OR method. CONCLUSION: OR and EVAR are effective modalities for the treatment of AAA. EVAR is a minimally invasive method, but the treatment costs are more than 8 times higher than the costs of surgical treatment. In terms of the VsZP cost control for the treatment of AAA, there must be clearly defined explicit indication criteria for EVAR. In terms of the costs for the treatment of AAA with "good risk" patients and those cases where there are no local obstacles for the surgical treatment (eg, colostoma, hostile abdomen, ren arcuatus and other), the surgical therapy is a "gold" standard. The health insurance company is a crucial regulator of the system of payment for provided medical care. The development of medical technology and the financial burden, on one hand, and the limited and scarce resources, on the other hand, are a source of "tension" between the health care providers and the regulators (insurance, Ministry of Health). One way to slow the "opening of the scissors" is to establish clear rules for the entry of new technologies into clinical practice, clearly defined costs (COI - cost of illness), and the usefulness and cost-effectiveness (CEA - cost-effectiveness analysis, ICER - incremental cost-effectiveness ratio, QALY - quality-adjusted life year). Despite the fact that it has beenmore than 20 years after the "velvet revolution", implementing the principles of health economics and health technology into practice has been managed in a rather weak way. The comparison of the costs of treatment is applicable in many areas of clinical medicine, and in the case of well-defined data it can be a source for the determination of ICER, CEA and QALYs. Key words: abdominal aortic aneurysms - surgery and endovascular treatment - costs.
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Aneurisma da Aorta Abdominal/economia , Aneurisma da Aorta Abdominal/terapia , Procedimentos Endovasculares/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Procedimentos Cirúrgicos Vasculares/economia , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
The energy loss functions (ELFs) of Fe and Ni have been derived from measured reflection electron energy loss spectroscopy (REELS) spectra by a reverse Monte Carlo analysis in our previous work. In this work, we present further improvements of ELFs for these metals. For Fe, we have updated ELFs at primary electron energies of 2 keV and 3 keV in a wider photon energy region (0-180 eV) with a better accuracy, which is verified by sum rules. Regarding to Ni, we supplement the ELF at primary energy of 5 keV and we also improve the data accuracy at 3 keV. Applying these new and more accurate ELFs we present the optical constants and dielectric functions for the two metals. The improvements were highlighted by comparing our present results with the previous data.
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Chronic restraint stress (CRS) induces the remodeling (i.e., retraction and simplification) of the apical dendrites of hippocampal CA3 pyramidal neurons in rats, suggesting that intrahippocampal connectivity can be affected by a prolonged stressful challenge. Since the structural maintenance of neuronal dendritic arborizations and synaptic connectivity requires neurotrophic support, we investigated the potential role of brain derived neurotrophic factor (BDNF), a neurotrophin enriched in the hippocampus and released from neurons in an activity-dependent manner, as a mediator of the stress-induced dendritic remodeling. The analysis of Golgi-impregnated hippocampal sections revealed that wild type (WT) C57BL/6 male mice showed a similar CA3 apical dendritic remodeling in response to three weeks of CRS to that previously described for rats. Haploinsufficient BDNF mice (BDNF(±) ) did not show such remodeling, but, even without CRS, they presented shorter and simplified CA3 apical dendritic arbors, like those observed in stressed WT mice. Furthermore, unstressed BDNF(±) mice showed a significant decrease in total hippocampal volume. The dendritic arborization of CA1 pyramidal neurons was not affected by CRS or genotype. However, only in WT mice, CRS induced changes in the density of dendritic spine shape subtypes in both CA1 and CA3 apical dendrites. These results suggest a complex role of BDNF in maintaining the dendritic and spine morphology of hippocampal neurons and the associated volume of the hippocampal formation. The inability of CRS to modify the dendritic structure of CA3 pyramidal neurons in BDNF(±) mice suggests an indirect, perhaps permissive, role of BDNF in mediating hippocampal dendritic remodeling.
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Fator Neurotrófico Derivado do Encéfalo/metabolismo , Região CA3 Hipocampal , Haploinsuficiência/genética , Células Piramidais , Estresse Psicológico/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/deficiência , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/patologia , Região CA3 Hipocampal/metabolismo , Região CA3 Hipocampal/patologia , Corticosterona/sangue , Espinhas Dendríticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Animais , Neurônios/metabolismo , Neurônios/patologia , Tamanho do Órgão , Células Piramidais/metabolismo , Células Piramidais/patologia , Ratos , Estresse Psicológico/patologiaRESUMO
Multi-drug resistant (MDR) Salmonella enterica serovar Newport (S. Newport) has established a reservoir in dairy cattle. Infected herds suffer significant mortality in both adult and young animals, posing a considerable economic loss to producers. Land application of manure from infected animals may further spread the pathogen into the agroecosystem, causing public health concerns. Previous work by our group demonstrated that the organism persisted in manure and manured soil for 6 to 10 mo under laboratory conditions. In the present study, we determined the survival characteristics of MDR S. Newport in a dairy lagoon, compost pile, and soil of a grass field under natural conditions using environmental sentinel chambers with an initial concentration of S. Newport around 7 log(10) per gram. In the static compost pile at 64 °C, S. Newport was eliminated within 18 h. In the dairy effluent lagoon, the pathogen survived for >137 d, whereas in the field soil, the organisms persisted for over 276 d. The survival of MDR S. Newport in both the lagoon and field soil followed a pattern of (1) an increase or plateau for a few days, (2) log-linear decline for 6 to 13 wk, and (3) a long tailing phase at low and variable concentration for 4 to 9 mo. Log reduction times (days required for 90% decrease in concentration) based on the log-linear decline phase were 7 d in the lagoon and 14 to 20 d in the soil. Conditions leading to faster inactivation during the initial phase do not necessarily translate into a quicker elimination of the pathogen. Regression models of the log-linear phase may be inaccurate for estimating complete pathogen elimination.
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Indústria de Laticínios , Viabilidade Microbiana , Salmonella enterica/fisiologia , Microbiologia do Solo , Animais , Bovinos , Esterco , Salmonella enterica/isolamento & purificaçãoRESUMO
A new and fully automated system with the interconnection of an Optical Immersion Probe (OIP) - pH meter - peristaltic pump was used to study the spectral and protolytic properties of carbocyanine the dyes 1,1',3,3,3',3'-hexamethylindocarbocyanine chloride (HIC); 1,1',3,3,3',3'-hexamethylindodicarbocyanine iodide (HIDC); and 3,3'-diethyloxadicarbocyanine iodide (DODC). This system can measure a large number of experimental points in a short time period. The effect of 32 various organic solvents on the UV-ViS spectra of the dyes was studied. The solvatochromic behaviour of studied dyes was characterized by positive solvatochromism for HIDC and negative solvatochromism for HIC and DODC. Through the application of a large number of experimental points, the protonation and hydrolysis constants of dyes were determined with high precision, where the confidence interval of the ÑK values is ±(0.001-0.005), compared with a confidence interval of ±(0.04-0.10) for standard procedures. The fully automated system presented is accurate, fast, environmentally friendly and promising for multiple analytical applications.
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A Schottky junction based on Ti3C2Tx MXene sheet integrated with marigold flower-like V2O5/CuWO4 heterojunction was designed and fabricated for robust ammonia sensing by monitoring the electrical resistance changes in air and ammonia. The electron transport behavior of the sensor was investigated by electrochemical analysis, ultraviolet photoelectron spectroscopy and reflection electron energy loss spectroscopy. Besides, negative zeta potential obtained for sensor components was in consistent with surface functional groups (e.g. OH and F) observed by XPS analysis helping better understanding of the ammonia sensing mechanism. The results desirably confirmed high sensitivity, selectivity, linear range (1-160 ppm), the limit of quantification, repeatability, long-term stability, very short response time (few seconds) and low working temperature (25 °C) of the sensor. The measurements on the resistance changes of the MXene/V2O5/CuWO4-based sensor under the exposure to various types of analytes (Ammonia, Acetone, Benzene, Chloroform, DMF, Ethanol, humidity (80%), Methanol and Toluene as well as NO, NO2, H2S, SO2, CO and CH4) at different concentrations revealed that the fabricated sensor is excellently selective to ammonia with ultra-high sensitivity. Intra-day stability (7 runs a day) and long-term stability (every 10 days over 70 days) as important sensor characteristics were investigated at 51 ppm and ambient temperature, which showed very good repeatability and recoverability in both short and long periods for sensing the ammonia. Overall, MXene/V2O5/CuWO4 was shown to be cost-effective, easy to handle and suitably applicable for simple, ultrafast and extremely efficient trace ammonia detection, which could be of high interest for future exhaled breath analysis and the development of a novel noninvasive diagnostic strategy to monitor chronic kidney disease to stop a large measure of unnecessary invasive testing.
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Amônia , Testes Respiratórios , Técnicas Eletroquímicas , Umidade , TemperaturaRESUMO
The actions of the endogenous peptide nociceptin (PNOC; previously abbreviated as N/OFQ) on the myometrium have not been investigated previously. Our aim was to study the presence and functional role of PNOC in the modulation of uterine contractility in pregnant rats at term. The presence of PNOC and its receptors (OPRL1; previously called NOP) in the uterus were detected by radioimmunoassay and radioligand-binding experiments. The PNOC-stimulated G protein activation was assessed by a [(35)S]GTPgammaS-binding technique. The effects of PNOC in uterine rings precontracted with KCl or oxytocin were also tested in vitro. Uterine levels of cAMP were measured by enzyme immunoassay. The K(+) channel blockers tetraethylammonium and paxilline were used to study the role of K(+) channels in mediating the uterine effects of PNOC. Both PNOC and OPRL1 were present in the uterus. PNOC revealed a maximum contraction inhibition of approximately 30%, which was increased to 40% by naloxone. Naloxone and pertussis toxin significantly attenuated the G protein-stimulating effect of PNOC. The uterine cAMP levels were elevated by PNOC and naloxone and after preincubation with pertussis toxin. Tetraethylammonium and paxilline reduced the contraction-inhibiting effect of PNOC and naloxone to approximately 10% and 15%, respectively. We presume that PNOC plays a role in regulating uterine contractility at term. Its effect is mediated partly by stimulatory heterotrimeric G (G(s)) proteins coupled to OPRL1 receptors and elevated cAMP levels, and also by Ca(2+)-dependent K(+) channels. Our results demonstrate a novel action and signaling pathway for PNOC that might be a potential drug target.
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Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Peptídeos Opioides/metabolismo , Gravidez/metabolismo , Receptores Opioides/metabolismo , Contração Uterina/metabolismo , Útero/metabolismo , Animais , AMP Cíclico/metabolismo , Feminino , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Técnicas In Vitro , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Ensaio Radioligante , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Radioisótopos de Enxofre/metabolismo , Receptor de Nociceptina , NociceptinaRESUMO
OBJECTIVE: Proteolytic degradation of aggrecan in articular cartilage is a hallmark feature of osteoarthritis (OA). The present study was aimed at developing a sensitive enzyme linked immunosorbent assay (ELISA) for the detection of aggrecanase-cleaved fragments of aggrecan in human serum and urine to facilitate the clinical development of aggrecanase inhibitors for OA. METHODS: The BC3 monoclonal antibody that detects the ARGS neoepitope sequence in aggrecanase-cleaved aggrecan was engineered and optimized using complementarity determining region (CDR)-saturation mutagenesis to improve its binding affinity to the neoepitope. A sandwich ELISA (BC3-C2 ELISA) was developed using the optimized alpha-ARGS antibody (BC3-C2) as capture antibody and a commercially available antibody directed against the hyaluronic-acid binding region (HABR) of aggrecan as detection antibody. Aggrecanase-cleaved fragments of aggrecan present in in vitro digests, human cartilage explant culture supernatants and in human synovial fluid, serum and urine were detected and quantified using this ELISA. RESULTS: The optimized antibody had a 4-log improvement in affinity for the ARGS containing peptide compared to the parental BC3 antibody, while maintaining the ability to not cross-react with a spanning peptide. The BC3-C2 ELISA demonstrated the ability to detect aggrecanase-cleaved aggrecan fragments in the native state, without the need for deglycosylation. This ELISA was able to measure aggrecanase-generated ARGS containing aggrecan fragments in human articular cartilage (HAC) explant cultures in the basal state (without cytokine stimulation). Treatment with an aggrecanase inhibitor resulted in a dose-dependent inhibition of ARGS neoepitope released into the culture supernatant. The ELISA assay also enabled the detection of ARGS containing fragments in human synovial fluid, serum and urine, suggesting its potential utility as a biomarker of aggrecanase activity. CONCLUSIONS: We have developed a novel ELISA using an optimized ARGS antibody and have demonstrated for the first time, an ELISA-based measurement of aggrecan degradation products in human serum and urine. This assay has the potential to serve as a mechanistic drug activity biomarker in the clinic and is expected to significantly impact/accelerate the clinical development of aggrecanase inhibitors and other disease modifying drugs for OA.
Assuntos
Proteínas ADAM/análise , Agrecanas/análise , Anticorpos Monoclonais , Cartilagem Articular/enzimologia , Ensaio de Imunoadsorção Enzimática/métodos , Fragmentos de Peptídeos/análise , Pró-Colágeno N-Endopeptidase/análise , Proteína ADAMTS4 , Agrecanas/imunologia , Biomarcadores , Cartilagem Articular/imunologia , Creatinina/urina , Humanos , Osteoartrite do Joelho/enzimologia , Fragmentos de Peptídeos/imunologia , Líquido Sinovial/enzimologiaRESUMO
The most commonly occurring atherosclerotic manifestations are peripheral artery diseases (PAD). Immune-mediated processes contribute to the development of atherosclerosis, and affect the diseases outcome. The aim of the present study was to assess various immune-competent cells, cytokines and chemokines in patients with PAD and to evaluate whether the base immunological values reflect the subsequent development of cardio/cerebrovascular symptoms. One hundred sixty patients with PAD were followed-up for 42 months. At the time of enrolment, we determined blood lymphocyte subpopulations, both T-helper (Th)1/Th2-type intracytoplasmic cytokines and soluble cytokines, chemokines. Intracellular cytokines were measured on phorbol-myristate-acetate- and ionomycine- stimulated cells. Lymphocyte subgroups were quantified by flow cytometry, soluble cytokines by ELISA and intracellular cytokine levels were measured by flow cytometry. The ankle-brachial index (ABI), indicator of atherosclerosis, was also evaluated. The clinical results were correlated with the immune-parameters to assess the input of immune-inflammatory events in the propagation of vascular manifestation. CD4(+) T-cell proportions in patients with PAD with cerebro- cardio-vascular manifestations were decreased, which further reduced in patients with fatal outcome. Of circulating chemokines, IL-8 (CXCL-8) was increased in patients with subsequent cerebro- cardio-vascular manifestations, compared to those without the symptoms, and further raised in patients with fatal outcome. The percentage of interferon (IFN)-gamma positive cells showed clear negative correlation with ABI. We conclude that altered peripheral lymphocyte subsets and cytokine/chemokine imbalance play important roles in the proinflammatory cascade and reflect disease severity in patients with PAD.
Assuntos
Doenças Cardiovasculares/imunologia , Transtornos Cerebrovasculares/imunologia , Interleucina-8/imunologia , Doenças Vasculares Periféricas/imunologia , Doenças Cardiovasculares/complicações , Transtornos Cerebrovasculares/complicações , Citocinas/imunologia , Feminino , Humanos , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Doenças Vasculares Periféricas/complicações , Fatores de Risco , Linfócitos T/imunologiaRESUMO
Managing P on dairy farms requires the assessment and monitoring of P status of the animals so that potential overfeeding may be minimized. Numerous published studies have demonstrated that for lactating dairy cows, increasing P concentrations in diets led to greater P excretion in feces. More recent work reported that inorganic P (P(i)) in 0.1% HCl extracts of feces (fecal extract P(i), g/kg) closely reflects dietary P changes. This has led to the proposal that 0.1% HCl fecal extract P(i) may serve as an indicator of the animal's P status (adequate or excessive) when compared with a benchmark value. Here, we present the results of an extensive evaluation of the proposed fecal P indicator test. With samples (n=575) from >90 farms, fecal total P (TP, g/kg) and fecal extract P were positively correlated with dietary P (X, g/kg): TP=1.92X - 0.17 (R2=0.36); fecal extract P=1.82X - 2.54 (R2=0.46). Fecal extract P was responsive to dietary P changes, whereas the remaining P, calculated as TP minus fecal extract P, was not. A provisional benchmark value of fecal extract P representing near-adequate P status was set at 4.75g/kg. Assessment of the farm data using the benchmark indicated that 316 out of 575 data points were associated with possible P overfeeding. Advantages of the fecal-based test over feed-based analysis to assess P status are discussed. The fecal extract P method is a simple and practical test that can be used as an assessment tool for helping dairy producers improve P management and reduce their environmental footprint.
Assuntos
Bovinos/fisiologia , Indústria de Laticínios/métodos , Fezes/química , Fósforo na Dieta/administração & dosagem , Animais , Bovinos/metabolismo , Dieta/veterinária , Feminino , Fósforo/análiseRESUMO
Breast cancer is characterized by oncobiosis, the abnormal composition of the microbiome in neoplastic diseases. The biosynthetic capacity of the oncobiotic flora in breast cancer is suppressed, as suggested by metagenomic studies. The microbiome synthesizes a set of cytostatic and antimetastatic metabolites that are downregulated in breast cancer, including cadaverine, a microbiome metabolite with cytostatic properties. We set out to assess how the protein expression of constitutive lysine decarboxylase (LdcC), a key enzyme for cadaverine production, changes in the feces of human breast cancer patients (n = 35). We found that the fecal expression of Escherichia coli LdcC is downregulated in lobular cases as compared to invasive carcinoma of no special type (NST) cases. Lobular breast carcinoma is characterized by low or absent expression of E-cadherin. Fecal E. coli LdcC protein expression is downregulated in E-cadherin negative breast cancer cases as compared to positive ones. Receiver operating characteristic (ROC) analysis of LdcC expression in lobular and NST cases revealed that fecal E. coli LdcC protein expression might have predictive values. These data suggest that the oncobiotic transformation of the microbiome indeed leads to the downregulation of the production of cytostatic and antimetastatic metabolites. In E-cadherin negative lobular carcinoma that has a higher potential for metastasis formation, the protein levels of enzymes producing antimetastatic metabolites are downregulated. This finding represents a new route that renders lobular cases permissive for metastasis formation. Furthermore, our findings underline the role of oncobiosis in regulating metastasis formation in breast cancer.
RESUMO
Eph receptor tyrosine kinases and their membrane-associated ligands, the ephrins, are essential regulators of axon guidance, cell migration, segmentation, and angiogenesis. There are two classes of vertebrate ephrin ligands which have distinct binding specificities for their cognate receptors. Multimerization of the ligands is required for receptor activation, and ephrin ligands themselves signal intracellularly upon binding Eph receptors. We have determined the structure of the extracellular domain of mouse ephrin-B2. The ephrin ectodomain is an eight-stranded beta barrel with topological similarity to plant nodulins and phytocyanins. Based on the structure, we have identified potential surface determinants of Eph/ephrin binding specificity and a ligand dimerization region. The high sequence similarity among ephrin ectodomains indicates that all ephrins may be modeled upon the ephrin-B2 structure presented here.