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The application of deep learning to image and video processing has become increasingly popular nowadays. Employing well-known pre-trained neural networks for detecting and classifying objects in images is beneficial in a wide range of application fields. However, diverse impediments may degrade the performance achieved by those neural networks. Particularly, Gaussian noise and brightness, among others, may be presented on images as sensor noise due to the limitations of image acquisition devices. In this work, we study the effect of the most representative noise types and brightness alterations on images in the performance of several state-of-the-art object detectors, such as YOLO or Faster-RCNN. Different experiments have been carried out and the results demonstrate how these adversities deteriorate their performance. Moreover, it is found that the size of objects to be detected is a factor that, together with noise and brightness factors, has a considerable impact on their performance.
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Metal-organic-frameworks (MOFs) are emerging materials used in the environmental electrochemistry community for Faradaic and non-Faradaic water remediation technologies. It has been concluded that MOF-based materials show improvement in performance compared to traditional (non-)faradaic materials. In particular, this review outlines MOF synthesis and their application in the fields of electron- and photoelectron-Fenton degradation reactions, photoelectrocatalytic degradations, and capacitive deionization physical separations. This work overviews the main electrode materials used for the different environmental remediation processes, discusses the main performance enhancements achieved via the utilization of MOFs compared to traditional materials, and provides perspective and insights for the further development of the utilization of MOF-derived materials in electrified water treatment.
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The hydrogenation of benzaldehyde to benzyl alcohol on carbon-supported metals in water, enabled by an external potential, is markedly promoted by polarization of the functional groups. The presence of polar co-adsorbates, such as substituted phenols, enhances the hydrogenation rate of the aldehyde by two effects, that is, polarizing the carbonyl group and increasing the probability of forming a transition state for H addition. These two effects enable a hydrogenation route, in which phenol acts as a conduit for proton addition, with a higher rate than the direct proton transfer from hydronium ions. The fast hydrogenation enabled by the presence of phenol and applied potential overcompensates for the decrease in coverage of benzaldehyde caused by competitive adsorption. A higher acid strength of the co-adsorbate increases the intensity of interactions and the rates of selective carbonyl reduction.
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AIMS: The simultaneous occurrence of two primary intracranial tumors is a rare event, especially if unrelated to radiotherapy or genetic disorders. We present two patients, both with two primary intracranial tumors simultaneously present at adjacent sites, in order to explore a possible mechanism of synchronous tumor formation. METHODS: We performed a molecular analysis of the K409Q mutation of the KLF4 gene, in addition to conventional immunohistochemistry. RESULTS: Preoperative gadolinium-enhanced magnetic resonance imaging revealed a necrotic mass with an irregular ring-like enhancement adjacent to a frontal meningioma in patient 1, and an infiltrative non-enhancing glial tumor with no evidence of another tumor in patient 2. Postoperative histological examination revealed the presence of two distinct tumors in both cases: secretory meningioma and glioblastoma in patient 1 and secretory meningioma and anaplastic astrocytoma in patient 2. Secretory meningiomas both showed the KLF4 K409Q mutation, while none of the glial tumors had it. CONCLUSIONS: To our knowledge, these are the first two cases reported of the simultaneous occurrence of secretory meningiomas with mutation of KLF4 in collision with a glioblastoma and an anaplastic astrocytoma, respectively. These collision tumors presumably have different molecular origins.
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Neoplasias Encefálicas/genética , Glioblastoma/genética , Glioma/genética , Fatores de Transcrição Kruppel-Like/genética , Neoplasias Meníngeas/genética , Meningioma/genética , Mutação/genética , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , Feminino , Glioblastoma/diagnóstico , Glioma/diagnóstico , Glioma/patologia , Humanos , Imuno-Histoquímica/métodos , Fator 4 Semelhante a Kruppel , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/patologia , Meningioma/diagnóstico , Meningioma/patologia , Adulto JovemRESUMO
Velaglucerase alfa is a glucocerebrosidase produced by gene activation technology in a human fibroblast cell line (HT-1080), and it is indicated as an enzyme replacement therapy (ERT) for the treatment of Gaucher disease type 1 (GD1). This multicenter, open-label, 12-month study examined the safety and efficacy of velaglucerase alfa in patients with GD1 previously receiving imiglucerase. Eligible patients, ≥2 years old and clinically stable on imiglucerase therapy, were switched to velaglucerase alfa at a dose equal to their prior imiglucerase dose. Infusion durations were 1 hr every other week. Forty patients received velaglucerase alfa (18 male, 22 female; four previously splenectomized; age range 9-71 years). Velaglucerase alfa was generally well tolerated with most adverse events (AEs) of mild or moderate severity. The three most frequently reported AEs were headache (12 of 40 patients), arthralgia (9 of 40 patients), and nasopharyngitis (8 of 40 patients). No patients developed antibodies to velaglucerase alfa. There was one serious AE considered treatment-related: a grade 2 anaphylactoid reaction within 30 min of the first infusion. The patient withdrew; this was the only AE-related withdrawal. Hemoglobin concentrations, platelet counts, and spleen and liver volumes remained stable through 12 months. In conclusion, adult and pediatric patients with GD1, previously treated with imiglucerase, successfully transitioned to velaglucerase alfa, which was generally well tolerated and demonstrated efficacy over 12 months' treatment consistent with that observed in the velaglucerase alfa phase 3 clinical trial program.
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Terapia de Reposição de Enzimas , Doença de Gaucher/tratamento farmacológico , Glucosilceramidase/deficiência , Adolescente , Adulto , Idoso , Criança , Esquema de Medicação , Substituição de Medicamentos , Feminino , Doença de Gaucher/enzimologia , Doença de Gaucher/genética , Glucosilceramidase/genética , Glucosilceramidase/farmacologia , Glucosilceramidase/uso terapêutico , Hemoglobinas/análise , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Resultado do TratamentoRESUMO
Microbial electrolysis cells (MECs) have demonstrated high-rate H2 production while concurrently treating wastewater, but the transition in scale from laboratory research to systems that can be practically applied has encountered challenges. It has been more than a decade since the first pilot-scale MEC was reported, and in recent years, many attempts have been made to overcome the barriers and move the technology to the market. This study provided a detailed analysis of MEC scale-up efforts and summarized the key factors that should be considered to further develop the technology. We compared the major scale-up configurations and systematically evaluated their performance from both technical and economic perspectives. We characterized how system scale-up impacts the key performance metrics such as volumetric current density and H2 production rate, and we proposed methods to evaluate and optimize system design and fabrication. In addition, preliminary techno-economic analysis indicates that MECs can be profitable in many different market scenarios with or without subsidies. We also provide perspectives on future development needed to transition MEC technology to the marketplace.
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Fontes de Energia Bioelétrica , Águas Residuárias , Hidrogênio , Eletrólise , TecnologiaRESUMO
Recombinant human idursulfase, an intravenous enzyme replacement therapy indicated for treatment of somatic symptoms of mucopolysaccharidosis II (Hunter syndrome), is anticipated to have minimal benefit for the cognitive impairment associated with the severe phenotype. Because intrathecal (IT) administration of enzyme replacement therapy for other lysosomal enzyme disorders has shown efficacy in animal models, an IT formulation of idursulfase (idursulfase-IT) and a drug-delivery device (subcutaneous port connected to a lumbar IT catheter) were developed for treating central nervous system (CNS) involvement. In this chronic safety study, cynomolgus monkeys were dosed weekly with IV idursulfase (0.5 mg/kg) and every four weeks with idursulfase-IT (3, 30, and 100 mg) for six months, with device and vehicle controls treated similarly (n = 6, all groups). Necropsies were performed twenty-four hours post-final IT dose or after a recovery period (four weeks post-final dose in vehicle-control, 3 mg, and 100 mg IT groups: n = 6). No clinical signs or gross central nervous system lesions were observed. Compared to controls, more pronounced cellular infiltrates in brain and spinal cord meninges were noted, which largely resolved after the recovery period. Central nervous sytem levels of idursulfase-IT were dose dependent, as determined by enzyme activity and immunohistochemistry. The no-observed-adverse-effect level of idursulfase-IT was 100 mg.
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Iduronato Sulfatase/toxicidade , Meninges/efeitos dos fármacos , Meninges/patologia , Animais , Estudos de Casos e Controles , Relação Dose-Resposta a Droga , Terapia de Reposição de Enzimas/métodos , Iduronato Sulfatase/administração & dosagem , Iduronato Sulfatase/sangue , Iduronato Sulfatase/líquido cefalorraquidiano , Imuno-Histoquímica , Bombas de Infusão Implantáveis , Injeções Espinhais , Macaca fascicularis , Masculino , Nível de Efeito Adverso não ObservadoRESUMO
The metabolic response when aerobic exercise is performed after the ingestion of glucose plus fructose is unclear. In the present study, we administered two beverages containing GluF (glucose+fructose) or Glu (glucose alone) in a randomized cross-over design to 20 healthy aerobically trained volunteers to compare the hormonal and lipid responses provoked during aerobic exercise and the recovery phase. After ingesting the beverages and a 15-min resting period, volunteers performed 30 min of moderate aerobic exercise. Urinary and blood samples were taken at baseline (t(-15)), during the exercise (t(0), t(15) and t(30)) and during the recovery phase (t(45), t(75) and t(105)). Plasma insulin concentrations were higher halfway through the exercise period and during acute recuperation (t(15) and t(75); P<0.05) following ingestion of GluF than after Glu alone, without any differences between the effects of either intervention on plasma glucose concentrations. Towards the end of the exercise period, urinary catecholamine concentrations were lower following GluF (t(45); P<0.05). Plasma triacylglycerol (triglyceride) concentrations were higher after the ingestion of GluF compared with Glu (t(15), t(30), t(45) and t(105); P<0.05). Furthermore, with GluF, we observed higher levels of lipoperoxides (t(15), t(30), t(45) and t(105); P<0.05) and oxidized LDL (low-density lipoprotein; t(30); P<0.05) compared with after the ingestion of Glu alone. In conclusion, hormonal and lipid alterations are provoked during aerobic exercise and recovery by the addition of a dose of fructose to the pre-exercise ingestion of glucose.
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Exercício Físico/fisiologia , Frutose/farmacologia , Glucose/farmacologia , Hormônios/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Adulto , Glicemia/metabolismo , Dieta , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/farmacologia , Suplementos Nutricionais , Epinefrina/urina , Humanos , Insulina/sangue , Lipídeos/sangue , Masculino , Norepinefrina/urina , Estado Nutricional , Adulto JovemRESUMO
Persistent short stature is one of the most frequent complications of being born small for gestational age (SGA) as almost 15% of such children have a low adult height. Additionally, individuals born SGA may have low lean body mass and increased central adiposity which put them at risk of long-term morbidity related to insulin resistance and metabolic disease. Onset of puberty appears at a normal age but comes relatively early for their actual height. There are studies that show that the pubertal growth spurt is moderately decreased in SGA and some girls may experience advanced pubarche and menarche. We have retrospectively analyzed 64 untreated SGA children and we have observed that adult height was lower than target height and positively correlated with maternal height, target height and height at onset of puberty; the tempo of puberty was very similar between SGA and controls but pubertal growth spurt was lower in SGA than in controls. The pathophysiology of postnatal growth failure is complex and different anomalies in the GH-IGF axis had been described. The effect of GH therapy on linear growth and adult height has been extensively studied in the last 15 years. In the short term, GH treatment produces an acceleration of growth with a significant increment of height which is dose dependent during the first 3-4 years. The long-term response is less dose dependent and the vast majority of short SGA children reach an adult height within normal standards and adequate for their target height. There is an important variation in the growth response of SGA children to GH indicating that SGA represents a heterogeneous condition in which response during the first year is the most important predictor of subsequent growth response. GH appears to be safe at the current doses employed but monitoring of IGF-I, IGFBP-3 and glucose metabolism is mandatory during therapy.
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Desenvolvimento Infantil/efeitos dos fármacos , Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Recém-Nascido Pequeno para a Idade Gestacional/crescimento & desenvolvimento , Adolescente , Estatura/efeitos dos fármacos , Estatura/fisiologia , Criança , Transtornos do Crescimento/fisiopatologia , Hormônio do Crescimento Humano/efeitos adversos , Hormônio do Crescimento Humano/sangue , Humanos , Recém-Nascido , Fator de Crescimento Insulin-Like I/análise , Puberdade/fisiologia , Resultado do TratamentoRESUMO
A protein concentrate from giant squid (Dosidicus gigas) was produced under acidic conditions and its functional-technological capability evaluated in terms of its gel-forming ability, water holding capacity and colour attributes. Technological functionality of the concentrate was compared with that of squid muscle and a neutral concentrate. Protein-protein aggregates insoluble at high ionic strength (I=0.5M), were detected in the acidic concentrate as result of processing with no preclusion of its gel-forming ability during the sol-to-gel thermal transition. Even though washing under acidic condition promoted autolysis of the myosin heavy chain, the acidic concentrate displayed an outstanding ability to gel giving samples with a gel strength of 455 and 1160gcm at 75% and 90% compression respectively, and an AA folding test grade indicative of high gel strength, elasticity, and cohesiveness. The process proved to be a good alternative for obtaining a functional protein concentrate from giant squid muscle.
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Conformational and thermal-rheological properties of acidic (APC) and neutral (NPC) protein concentrates were evaluated and compared to those of squid (Dosidicus gigas) muscle proteins (SM). Surface hydrophobicity, sulfhydryl status, secondary structure profile, differential scanning calorimetry and oscillatory dynamic rheology were used to evaluate the effect of treatments on protein properties. Acidic condition during the washing process (APC) promoted structural and conformational changes in the protein present in the concentrate produced. These changes were enhanced during the heat setting of the corresponding sol. Results demonstrate that washing squid muscle under the proposed acidic conditions is a feasible technological alternative for squid-based surimi production improving its yield and gel-forming ability.
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Decapodiformes/química , Manipulação de Alimentos/métodos , Proteínas Musculares/química , Alimentos Marinhos/análise , Animais , Varredura Diferencial de Calorimetria , Concentração de Íons de Hidrogênio , Músculos/química , ReologiaRESUMO
OBJECTIVE: Adjunctive treatment with L-methylfolate calcium significantly improved treatment outcomes in patients with major depressive disorder (MDD) and an inadequate response to antidepressants. This post hoc exploratory analysis evaluated baseline concentrations of cytokines (interleukin [IL]-1α, IL-1ß, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-13, and IL-17; tumor necrosis factor α [TNF-α]; and interferon γ [IFN-γ]), high-sensitivity C-reactive protein (hsCRP), insulin, adiponectin and leptin and body mass index (BMI [kg/m2]) on L-methylfolate calcium treatment response. METHOD: Adults with DSM-IV MDD and an inadequate response to a selective serotonin reuptake inhibitor (SSRI) were eligible. Patients were randomized 3:3:2 according to the sequential parallel comparison design to placebo versus placebo, placebo versus L-methylfolate calcium (15 mg/d), or L-methylfolate calcium versus L-methylfolate calcium (15 mg/d) during two 30-day phases. The primary outcome was change on the 17-item Hamilton Depression Rating Scale (HDRS-17). Treatment effect with 95% CIs was estimated from baseline concentrations of individual biomarkers and combinations. Cytokines were measured by immunoassay; adiponectin, insulin, and leptin by radioimmunoassay; and hsCRP by a standard turbidimetric assay. The effects of baseline biomarker levels (above and below the median) on outcome were analyzed. The first participant was enrolled July 14, 2009, and the last participant completed April 28, 2011. RESULTS: Mean change on HDRS-17 from baseline was significantly improved with L-methylfolate calcium versus placebo (pooled treatment effect, -2.74; 95% CI, -4.99 to -0.48; P = .017) overall and for those with baseline BMI ≥ 30 (pooled treatment effect, -4.66; 95% CI, -7.22 to -1.98; P = .001) but not BMI < 30. Pooled mean changes in depression across treatment for baseline levels of individual markers above median were significant (L-methylfolate calcium vs placebo) for TNF-α, IL-8, hsCRP, and leptin (pooled treatment effects, -4.33 to -3.94 [P ≤ .02]) and for combinations of BMI ≥ 30 with elevated levels of TNF-α, IL-6, IL-8, hsCRP, and leptin (pooled treatment effects, -6.31 to -3.98 [P ≤ .05]). CONCLUSIONS: In this exploratory analysis, inflammatory and obesity-related factors were associated with greater symptom improvement with L-methylfolate calcium. Combinations of BMI ≥ 30 with elevated IL-6, IL-8, hsCRP, TNF-α, and leptin predicted improved response to L-methylfolate calcium in MDD patients with an inadequate antidepressant response. Further studies are necessary to confirm these findings. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00955955.
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Transtorno Depressivo Maior/tratamento farmacológico , Glutamatos/farmacologia , Inflamação/tratamento farmacológico , Obesidade/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Adulto , Biomarcadores/sangue , Comorbidade , Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/epidemiologia , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Glutamatos/administração & dosagem , Humanos , Inflamação/sangue , Inflamação/epidemiologia , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/epidemiologiaRESUMO
An intrathecal (IT) formulation of recombinant human heparan N-sulfatase (HNS) is under development for the treatment of the neurological symptoms of mucopolysaccharidosis IIIA (MPS IIIA; Sanfilippo A disease), the defining clinical feature of this disorder. Since the average age of MPS IIIA patients is 4.5 years, the pivotal toxicology studies for HNS were conducted in juvenile cynomolgus monkeys to evaluate the effects on the developing brain. Monkeys were implanted with an IT-lumbar drug delivery device and dosed every other week by slow bolus administration (1.5, 4.5, or 8.3 mg/dose HNS for 6 months; 12 doses), with device and vehicle controls receiving phosphate-buffered saline or vehicle, respectively. Eight animals per group (four/sex) were necropsied at 3 and 6 months (device control group necropsied at 3 months), and eight animals from the vehicle group and the three HNS-dosed groups were necropsied 1 month after the final IT dose. No HNS-related clinical signs or gross central nervous system lesions were observed. Compared with controls, there were cellular infiltrates of slight-to-minimal mean severity in the meninges/perineurium surrounding the brain/spinal cord correlating with transient increases in cerebrospinal fluid (CSF) leukocytes, predominantly eosinophils, which largely resolved 1 month after the final dose. These changes were not associated with any adverse morphological changes in the brain or spinal cord. There appeared to be a dose-related trend toward higher mean CSF HNS levels and in tissue HNS activity levels in the brain, spinal cord, and liver. The no-observed-adverse-effect-level was 8.3 mg/dose given every other week, the highest dose administered.
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Anti-drug antibodies are elicited by virtually all therapeutic proteins, and standardized assays are required for clinical monitoring of patients as well as for comparing antibody response to different therapeutic proteins in clinical trials. Velaglucerase alfa and imiglucerase are enzyme replacement therapies for the long-term treatment of type 1 Gaucher disease, a lysosomal storage disease resulting from an inherited deficiency of the enzyme glucocerebrosidase. We used state-of-the-art tools to develop a panel of assays for detection and characterization of antibody responses to velaglucerase alfa and imiglucerase. Highly-sensitive, direct bridging electrochemiluminescence screening assays were developed using samples from treatment-naïve individuals with type 1 Gaucher disease to set cut points. A mouse anti-glucocerebrosidase monoclonal antibody used as a calibrator was shown to have similar affinity and binding kinetics for anti-velaglucerase alfa and anti-imiglucerase antibodies. A quantitative radioimmunoprecipitation assay for IgG antibodies was developed to eliminate false-positives from the highly sensitive screening assay. Using 59 samples from treatment-naïve individuals with type 1 Gaucher disease, the confirmatory cut points were calculated to be 1.42 ng/mL for anti-velaglucerase alfa antibodies and 3.23 ng/mL for anti-imiglucerase antibodies. Isotype-specific indirect electrochemiluminescence assays were developed for IgE, IgA, and IgM subclasses. The IgE subclass assay was shown to be more sensitive than the confirmatory assay using sheep anti-glucocerebrosidase polyclonal antibody cross-linked with fragments specific to human IgE, with cut points for anti-velaglucerase alfa or anti-imiglucerase antibodies determined to be 0.53 and 0.55 ng/mL, respectively. An assay that detects inhibition in vitro of velaglucerase alfa and imiglucerase hydrolysis of a synthetic substrate in the presence of antibodies was developed to test for neutralizing antibodies. Using 52 individual healthy human donor samples and 35 samples from treatment-naïve individuals with type 1 Gaucher disease, cut points for the velaglucerase alfa and imiglucerase neutralizing antibody assays were determined to be 20%, such that a sample with greater than 20% inhibition of enzyme activity in the presence of antibodies was considered positive for neutralizing antibodies. In conclusion, highly sensitive and equivalent methods were developed and validated to directly compare antibody response to velaglucerase alfa and imiglucerase treatments in patients with Gaucher disease, and may contribute to future internationally standardized assays for antibody detection in patients with Gaucher disease.
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Anticorpos/imunologia , Terapia de Reposição de Enzimas , Doença de Gaucher/imunologia , Glucosilceramidase/uso terapêutico , Animais , Anticorpos/sangue , Técnicas Eletroquímicas/métodos , Doença de Gaucher/sangue , Doença de Gaucher/tratamento farmacológico , Glucosilceramidase/imunologia , Humanos , Imunoensaio/métodos , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Medições Luminescentes/métodos , Camundongos , Ensaio de Radioimunoprecipitação , Reprodutibilidade dos TestesRESUMO
Tissue factor (TF), or thromboplastin, is a cell membrane-associated glycoprotein composed, in full length, of cytoplasmic, transmembrane, and extracellular domains. It functions as a cofactor in a complex with factor VII (FVII), generating activated factor VII (FVIIa) and initiating blood coagulation. The prothrombin time (PT) assay uses TF as the in vitro activator of coagulation under defined conditions, and it is primarily used to diagnose and manage the extrinsic-pathway factor defficiencies. To overcome the limitations of natural-source TF, we have expressed the mature full-length recombinant rabbit TF (rRTF) protein in Pichia pastoris. Isolation, by purification by immobilized metal-affinity chromatography, of full-length rRTF was facilitated by engineering a (His)(6) tail on its C-terminus, which maximizes the selection of rRTF with intact transmembrane and cytoplasmic domains, critical for proper activity. A PT reagent that incorporates this purified rRTF has performance characteristics similar to those of PT reagents made with natural TF as indicated in method comparison studies, and shows lot-to-lot consistency and reproducibility.
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Pichia/genética , Tempo de Protrombina , Proteínas Recombinantes/metabolismo , Tromboplastina/metabolismo , Animais , Clonagem Molecular , DNA Complementar , Fator VII/metabolismo , Fator VIIa/metabolismo , Expressão Gênica , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Reprodutibilidade dos Testes , Tromboplastina/genética , Tromboplastina/isolamento & purificaçãoRESUMO
Protein C activators are proteases that activate protein C in the mammalian coagulation system. A reptilian protein C activator is a critical component in current functional assays for protein C, its cofactor protein S, as well as for the overall status of the protein C pathway. We have constructed a synthetic gene for a protein C activator, based on a published snake-venom polypeptide sequence. This recombinant protein C activator was expressed in Pichia pastoris as a secreted glycoprotein (ILPCA) using the AOX1 promoter and the alpha-factor signal sequence. A fermentation protocol was developed that produced about 150 mg/L biologically active ILPCA secreted in the fermented broth. A two-step purification scheme was devised to purify ILPCA to approximately 80% purity. The ILPCA produced has an apparent molecular weight of approximately 68 kDa and a deglycosilated molecular weight of 28 kDa. Steady-state kinetic analysis reveals that ILPCA activates purified human protein C with a K(m) of 77 nM and a k(cat) of 0.39 s(-1). In conclusion, ILPCA is a recombinant protein that can be produced reliably and in large quantities under controlled manufacturing conditions, activates protein C, and can be used in coagulation assays as an alternative to native venom preparations.
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Oligopeptídeos/biossíntese , Oligopeptídeos/metabolismo , Pichia/genética , Proteína C/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/metabolismo , Animais , Sequência de Bases , Fermentação , Engenharia Genética , Humanos , Cinética , Dados de Sequência Molecular , Oligopeptídeos/genética , Regiões Promotoras Genéticas/genética , Proteínas Recombinantes/genética , Venenos de Serpentes/químicaRESUMO
Se realizó un estudio métrico de la producción científica cubana sobre esteroides indizada en Scopus desde 1996 hasta el 2006, con vistas a identificar los autores y revistas más productivas, los diferentes equipos de coautoría; así como los principales frentes de investigación. Se obtuvieron 79 artículos, firmados por un total de 220 autores. El índice de coautoría fue de 4,81. Los artículos se publicaron en 49 revistas de 13 países. Se observó un crecimiento de la producción científica durante el período, aunque aún no se logró alcanzar una producción elevada en revistas altamente especializadas en el tema. El 59,5 % de los artículos fue citado, y el promedio de citas recibidas por artículo fue de 3,25. Se identificaron redes de colaboración que permitieron la identificación de los principales frentes de investigación sobre esteroides, los cuales estuvieron en correspondencia con las estructuras de conocimiento observadas en las redes de coocurrencia de términos y descriptores. Los cinco núcleos temáticos fundamentales identificados en la producción científica cubana sobre esteroides se relacionaron con: la síntesis de esteroides, brasinosteroides y sus análogos; los efectos y consecuencias de su uso como anticonceptivos y abortivos; su aplicación en el tratamiento de diversas enfermedades como el asma y la alergia; la biotransformación de los esteroides; así como la extracción de esteroides a partir de fuentes naturales.
The present work is a bibliometric study of the Cuban scientific production on steroids indexed by SCOPUS, from 1996 to 2006, in order to identify the most productive authors and journals, the different co-authorship teams, and the main research fronts. It was obtained a total of 79 articles, signed by 220 authors. The co-authorship index was 4.81. The papers were published in 49 journals from 13 countries. A growth of the scientific production during the period was observed; however, it has not been achieved a remarked production in highly specialized journals yet. 59.5 % of the articles were cited, and the average of citation per article was 3.25. There were identified collaboration networks that allowed the analysis of the main research fronts on steroids, which were in correspondence with the knowledge structures observed in the co-occurrence networks of terms and descriptors. The main thematic cores identified in the Cuban scientific production on steroids were related to the synthesis of steroids, brassinosteroids and analogues; the effects and consequences of their use as contraceptive and aborting drugs; their application in the treatment of diseases like asthma and allergy; the steroids bioconversion; and the extraction of steroids from natural sources.
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Se realizó un estudio métrico de la producción científica mundial sobre biodiesel compilada en el Web of Science, con vistas a identificar los autores, países, instituciones y revistas más productivas; así como el idioma de los artículos, la tipología documental, las categorías temáticas y los descriptores presentes en los registros. Se obtuvieron 1 022 artículos, firmados por un total de 1 857 autores. El índice de co-autoría fue de 3,04. Los artículos fueron publicados en 232 revistas. Se identificó un total de 565 instituciones de 56 países. Se observó un crecimiento exponencial de la producción científica durante los últimos 15 años.
The current paper is a bibliometric study of the world scientific production on biodiesel compiled in the Web of Science, in order to identify the most productive authors, countries, institutions and journals; as well as the languages of the articles, documental typology, ISI subject categories, and keywords presented in the registries. It was obtained a total of 1022 articles, signed by 1857 authors. The co-authorship index was 3.04. The papers were published in 232 journals. A total of 565 institutions from 56 countries were identified. An exponential growth of the scientific production during the last 15 years was observed.
Assuntos
Energia não Convencional , Indicadores de Produção CientíficaRESUMO
Se realizó un estudio métrico de la producción científica cubana sobre dengue, indizada en Scopus desde 1981 hasta el 2006, con vistas a identificar los autores y revistas más productivas, los diferentes equipos de coautoría; así como los principales frentes de investigación tratados durante el período. Se obtuvieron 163 artículos, firmados por un total de 278 autores. El índice de coautoría fue de 5,53. Los artículos se publicaron en 45 revistas de 12 países. El 64,4 % de los artículos fue citado, y el promedio de citas recibidas por artículo fue de 6,2. La institución líder en la investigación cubana sobre dengue fue el Instituto de Medicina Tropical "Pedro Kourí", presente en más del 90 % de los trabajos. El 83,3 % de los autores más productivos proceden de esta institución. Se observó un crecimiento significativo de la producción científica durante los últimos 25 años, a causa del incremento de los episodios moderados reportados desde 1997 hasta el presente. Los investigadores cubanos han estudiado diferentes datos clínicos, virológicos y epidemiológicos acerca del dengue, e identificaron como causas de una posible rea-parición de la enfermedad en Cuba, el incremento de la migración hacia el área de personas provenientes de regiones donde la enfermedad es endémica, un alto nivel de infestación de los vectores; así como el incumplimiento de las medidas para la erradicación del vector.
A bibliometric study of the Cuban scientific production on dengue indexed by SCOPUS, from 1981 to 2006, was conducted in order to identify the most productive authors and journals, the different co-authorship teams, and the main research fronts treated during this period. 163 articles signed by 278 authors were obtained. The co-authorship index was 5.53. The papers were published in 45 journals from 12 countries. 64.4 % of the articles were cited, and the average of citation per article was 6.2. The leading institution in the Cuban research on dengue was "Pedro Kourí" Institute of Tropical Medicine, which was present in more than 90 % of the articles. 83.3 % of the most productive authors are from this institute. A remarked growth of the scientific production was observed during the last 25 years, due to the increase of the moderate episodes reported from 1997 up to the present. The Cuban researchers have studied different clinical, virological, and epidemiological data about dengue, and they have identified as causes of a possible re-appearance of the disease in Cuba, the increasing migration to the area of people from regions where the disease is endemic, a high level of vector infestation, and the nonfulfillment of the measures to eradicate the vector.
RESUMO
Las neurociencias constituyen uno de los frentes de investigación más visibles de la producción científica de Cuba. Como sector de la investigación, ellas se caracterizan por el alto nivel de colaboración entre sus especialistas, citación y una gran multidisciplinariedad. En el presente trabajo se analizaron las estadísticas de producción y el uso de una muestra de científicos cubanos altamente productivos en esta área. El estudio sistemático del quehacer de los neurocientíficos cubanos mediante indicadores basados en análisis de citas, objetivo principal del presente estudio, revelará en el futuro con mayor nivel de detalle las características de su producción documental, a la vez que será un instrumento imprescindible para una mejor evaluación de su desempeño como investigadores, así como de su eficiencia científica.
Neurosciences are one of the most visible research fronts in the scientific production of Cuba. As research area they are characterized by high degree of collaboration among there specialists, citation and multidisciplinarity. The production and use statistics from high productive Cuban scientists in this sector were analyzed. The systematic study of Cuban Neuroscientists activity through indicators based on citation analysis, the main objective of the current work, will show in the future the characteristics of its documental production with a more levels of detail, at the same time that it will become an essential tool for a better evaluation of its performances and scientific efficiency.