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1.
Tech Coloproctol ; 27(11): 995-1005, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37414915

RESUMO

PURPOSE: Complete mesocolic excision (CME) has been associated with improved oncological outcomes in treatment of colon cancer. However, widespread adoption is limited partly because of the technical complexity and perceived risks of the approach. The aim of out study was to evaluate the safety of CME compared to standard resection and to compare robotic versus laparoscopic approaches. METHODS: Two parallel searches were undertaken in MEDLINE, Embase and Web of Science databases 12 December 2021. The first was to evaluate IDEAL stage 3 evidence to compare complication rates as a surrogate marker of perioperative safety between CME and standard resection. The second independent search compared lymph node yield and survival outcomes between minimally invasive approaches. RESULTS: There were four randomized control trials (n = 1422) comparing CME to standard resection, and three studies comparing laparoscopic (n = 164) to robotic (n = 161) approaches. Compared to standard resection, CME was associated with a reduction in Clavien-Dindo grade 3 or higher complication rates (3.56% vs. 7.24%, p = 0.002), reduced blood loss (113.1 ml vs. 137.6 ml, p < 0.0001) and greater mean lymph node harvest (25.6 vs. 20.9 nodes, p = 0.001). Between the robotic and laparoscopic groups, there were no significant differences in complication rates, blood loss, lymph node yield, 5-year disease-free survival (OR 1.05, p = 0.87) and overall survival (OR 0.83, p = 0.54). CONCLUSIONS: Our study demonstrated improved safety with CME. There was no difference in safety or survival outcomes between robotic and laparoscopic CME. The advantage of a robotic approach may lie in the reduced learning curve and an increased penetration of minimally invasive approach to CME. Further studies are required to explore this. PROSPERO ID: CRD42021287065.


Assuntos
Neoplasias do Colo , Laparoscopia , Mesocolo , Procedimentos Cirúrgicos Robóticos , Robótica , Humanos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Excisão de Linfonodo/efeitos adversos , Colectomia/efeitos adversos , Neoplasias do Colo/patologia , Mesocolo/cirurgia , Mesocolo/patologia , Laparoscopia/efeitos adversos , Resultado do Tratamento
2.
Osteoarthritis Cartilage ; 30(8): 1091-1102, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35339693

RESUMO

OBJECTIVES: Proteolytic destruction of articular cartilage, a major pathogenic mechanism in osteoarthritis (OA), was not previously investigated by terminomics strategies. We defined the degradome of human knee OA cartilage and the contribution therein of the protease HtrA1 using Terminal Amine Isotopic Labeling of Substrates (TAILS). DESIGN: Proteins from OA cartilage taken at knee arthroplasty (n = 6) or separately, from healthy cartilage incubated in triplicate with/without active HtrA1, were labeled at natural and proteolytically cleaved N-termini by reductive dimethylation, followed by trypsin digestion, enrichment of N-terminally labeled/blocked peptides, tandem mass spectrometry and positional peptide annotation to identify cleavage sites. Biglycan proteolysis by HtrA1 was validated biochemically and Amino-Terminal Oriented Mass Spectrometry of Substrates (ATOMS) was used to define the HtrA1 cleavage sites. RESULTS: We identified 10,155 unique internal peptides from 2,162 proteins, suggesting at least 10,797 cleavage sites in OA cartilage. 7,635 internal peptides originated in 371 extracellular matrix/secreted components, many undergoing extensive proteolysis. Rampant ragging of protein termini suggested pervasive exopeptidase activity. HtrA1, the most abundant protease in OA cartilage, experimentally generated 323 cleavages in 109 cartilage proteins, accounting for 171 observed cleavages in the OA degradome. ATOMS identified HtrA1 cleavage sites in a selected substrate, biglycan, whose direct cleavage by HtrA1 was thus orthogonally validated. CONCLUSIONS: OA cartilage demonstrates widespread proteolysis by endo- and exopeptidases. HtrA1 contributes broadly to cartilage proteolysis. Forward degradomics of OA cartilage together with reverse degradomics of proteases active in OA, e.g., HtrA1, can potentially fully annotate OA proteolytic pathways and provide new biomarkers.


Assuntos
Cartilagem Articular , Serina Peptidase 1 de Requerimento de Alta Temperatura A , Peptídeo Hidrolases , Biglicano/metabolismo , Cartilagem Articular/metabolismo , Serina Peptidase 1 de Requerimento de Alta Temperatura A/metabolismo , Humanos , Peptídeo Hidrolases/metabolismo , Peptídeos/metabolismo , Proteínas/metabolismo , Proteólise , Espectrometria de Massas em Tandem
3.
Sci Robot ; 6(58): eabf1888, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34550719

RESUMO

During gait neurorehabilitation, many factors influence the quality of gait patterns, particularly the chosen body-weight support (BWS) device. Consequently, robotic BWS devices play a key role in gait rehabilitation of people with neurological disorders. The device transparency, support force vector direction, and attachment to the harness vary widely across existing robotic BWS devices, but the influence of these factors on the production of gait remains unknown. Because this information is key to designing an optimal BWS, we systematically studied these determinants in this work. We report that with a highly transparent device and a conventional harness, healthy participants select a small backward force when asked for optimal BWS conditions. This unexpected finding challenges the view that during human-robot interactions, humans predominantly optimize energy efficiency. Instead, they might seek to increase their feeling of stability and safety. We also demonstrate that the location of the attachment points on the harness strongly affects gait patterns, yet harness attachment is hardly reported in literature. Our results establish principles for the design of BWS devices and personalization of BWS settings for gait neurorehabilitation.


Assuntos
Sistemas Homem-Máquina , Reabilitação Neurológica/métodos , Robótica , Fenômenos Biomecânicos , Peso Corporal , Calibragem , Desenho de Equipamento , Feminino , Marcha , Humanos , Masculino , Aparelhos Ortopédicos , Segurança do Paciente , Interface Usuário-Computador , Caminhada
4.
Gynecol Oncol Rep ; 28: 141-144, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31080864

RESUMO

•<1% of cervical cancers are sarcomas.•Data on neurofibrosarcoma management is scarce.•Larotrectinib is approved for NTRK1 gene fusion tumors without acquired resistance.•Targeted therapy of tumor genes may expand treatment for a rare cervical sarcoma.

5.
Int J Numer Method Biomed Eng ; 34(5): e2960, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29316347

RESUMO

High-fidelity, predictive fluid flow simulations of the interactions between the rising thermal plumes from forced air warming blower and the ultra-clean ventilation air in an operating room (OR) are conducted to explore whether this complex flow can impact the dispersion of squames to the surgical site. A large-eddy simulation, accurately capturing the spatiotemporal evolution of the flow in 3 dimensions together with the trajectories of squames, is performed for a realistic OR consisting of an operating table (OT), side tables, surgical lamps, medical staff, and a patient. Two cases are studied with blower-off and blower-on together with Lagrangian trajectories of 3 million squames initially placed on the floor surrounding the OT. The large-eddy simulation results show that with the blower-off, squames are quickly transported by the ventilation air away from the table and towards the exit grilles. In contrast, with the hot air blower turned on, the ventilation airflow above and below the OT is disrupted significantly. The rising thermal plumes from the hot air blower drag the squames above the OT and the side tables and then they are advected downwards toward the surgical site by the ventilation air from the ceiling. Temporal history of the number of squames reaching 4 imaginary boxes surrounding the side tables, the OT, and the patient's knee shows that several particles reach these boxes for the blower-on case.


Assuntos
Salas Cirúrgicas/métodos , Ventilação , Temperatura Alta , Humanos
6.
Haemophilia ; 24(1): 104-112, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28833808

RESUMO

INTRODUCTION: Trenonacog alfa (IB1001) is a recombinant factor IX (rFIX) manufactured in Chinese hamster ovary (CHO) cells. IB1001 was evaluated in a multicentre clinical trial with haemophilia B patients. AIM: The aim was to establish IB1001 pharmacokinetic non-inferiority to comparator rFIX, safety and efficacy in previously treated patients (PTPs) with haemophilia B. METHODS: Subjects were severe or moderately severe haemophilia B adult and adolescent PTPs with no history of FIX inhibitors. RESULTS: IB1001 PK non-inferiority to comparator rFIX was demonstrated through ratio of AUC0-∞ in 32 subjects. IB1001 was well tolerated in all 76 treated subjects; the most common adverse drug reaction was headache (2.6% of subjects) and there were no reports of FIX inhibitors. Transient non-inhibitory binding FIX antibodies and anti-CHO cell protein antibodies developed in 21% and 29% of subjects respectively; no safety concerns were associated with development of these antibodies. Prophylaxis (mean duration ± SD: 17.9 ± 9.6 months, mean dose: 55.5 ± 12.9 IU/kg, median 1.0 infusion per week) was effective in preventing bleeds (median annual bleed rate: 1.52, interquartile range: 0.0-3.46). One or two IB1001 infusions resolved 84% of the bleeds, while for 84% of treatments haemostatic efficacy of IB1001 was rated excellent or good. IB1001 haemostatic efficacy for all 19 major surgeries was rated adequate or better than adequate. CONCLUSIONS: IB1001 is safe and efficacious for treatment of bleeds, routine prophylaxis and perioperative management in haemophilia B patients.


Assuntos
Fator IX/uso terapêutico , Hemofilia B/tratamento farmacológico , Adolescente , Adulto , Área Sob a Curva , Inibidores dos Fatores de Coagulação Sanguínea/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Fator IX/efeitos adversos , Fator IX/farmacocinética , Meia-Vida , Cefaleia/etiologia , Hemofilia B/patologia , Hemorragia/prevenção & controle , Humanos , Masculino , Curva ROC , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapêutico , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
7.
J Thromb Haemost ; 16(2): 253-261, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29220876

RESUMO

Essentials Congenital afibrinogenemia causes a potentially life-threatening bleeding and clotting tendency. Two human fibrinogen concentrates (HFCs) were compared in a randomized pharmacokinetic study. Bioequivalence was not shown for AUCnorm , which was significantly larger for the new HFC. Increases in clot strength were comparable, and no thromboses or deaths occurred in the study. SUMMARY: Background Human fibrinogen concentrate (HFC) corrects fibrinogen deficiency in congenital a-/hypofibrinogenemia. Objectives To assess pharmacokinetics (PK), effects on thromboelastometry maximum clot firmness (MCF), and safety of a new double virus-inactivated/eliminated, highly purified HFC vs. active control. Patients/Methods In this multinational, randomized, phase II, open-label, crossover study in 22 congenital afibrinogenemia patients aged ≥ 12 years, 70 mg kg-1 of new HFC (FIBRYGA, Octapharma AG) or control (Haemocomplettan® P/RiaSTAP™, CSL Behring GmbH) were administered, followed by crossover to the other concentrate. Fibrinogen activity, PK and MCF in plasma were assessed. Results The concentrates were not bioequivalent for the primary endpoint, AUCnorm (mean ratio, 1.196; 90% confidence interval [CI], 1.117, 1.281). Remaining PK parameters (Cmaxnorm , IVR, t1/2 , MRT) reflected bioequivalence between concentrates, except for clearance (mean ratio, 0.836; 90% CI, 0.781, 0.895) and Vss (mean ratio, 0.886; 90% CI, 0.791, 0.994). Mean AUCnorm was significantly larger for the new HFC (1.62 ± 0.45 vs. 1.38 ± 0.47 h kg g L-1  mg-1 , P = 0.0001) and mean clearance was significantly slower (0.665 ± 0.197 vs. 0.804 ± 0.255 mL h-1  kg-1 , P = 0.0002). Mean MCF increased from 0 mm to 9.68 mm (new HFC) and 10.00 mm (control) 1-hour post-infusion (mean difference, -0.32 mm; 95% CI, -1.70, 1.07, n.s.). No deaths, thromboses, viral seroconversions or serious related adverse events occurred. Conclusions Bioequivalence was not demonstrated for AUCnorm , clearance and Vss . Larger AUCnorm and slower clearance were observed for the new HFC. Remaining pharmacokinetic parameters reflected bioequivalence to control. Safety profiles and increases in clot strength were comparable between concentrates.


Assuntos
Afibrinogenemia/tratamento farmacológico , Coagulação Sanguínea/efeitos dos fármacos , Coagulantes/administração & dosagem , Coagulantes/farmacocinética , Fibrinogênio/administração & dosagem , Fibrinogênio/farmacocinética , Adolescente , Adulto , Afibrinogenemia/sangue , Afibrinogenemia/diagnóstico , Afibrinogenemia/genética , Ásia , Criança , Coagulantes/efeitos adversos , Estudos Cross-Over , Europa (Continente) , Feminino , Fibrinogênio/efeitos adversos , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Equivalência Terapêutica , Tromboelastografia , Resultado do Tratamento , Estados Unidos , Adulto Jovem
8.
J Vet Intern Med ; 31(2): 532-538, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28158899

RESUMO

Musladin-Lueke syndrome (MLS), previously termed Chinese Beagle syndrome, is an autosomal-recessive connective tissue disorder characterized by extensive fibrosis of the skin and joints that was first identified in Beagles in the 1970s. Recent research identified a founder mutation (c.660C>T; p.R221C) in the ADAMTSL2 gene in Beagles with MLS. Here, we report the detailed clinical phenotype and laboratory findings in 2 Beagles affected with MLS. We discuss these findings in relation to the human disorder geleophysic dysplasia (GD), which also arises from recessive ADAMTSL2 mutations, and recent findings in Adamtsl2-deficient mice.


Assuntos
Doenças do Cão/genética , Artropatias/veterinária , Anormalidades da Pele/veterinária , Animais , Doenças do Desenvolvimento Ósseo/genética , Doenças do Desenvolvimento Ósseo/patologia , Doenças do Cão/patologia , Cães , Feminino , Humanos , Artropatias/genética , Artropatias/patologia , Deformidades Congênitas dos Membros/genética , Deformidades Congênitas dos Membros/patologia , Masculino , Camundongos , Fenótipo , Anormalidades da Pele/genética , Anormalidades da Pele/patologia
9.
Photosynth Res ; 2013 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-24122336

RESUMO

Reactive oxygen species (ROS) are inevitably generated as by-products of respiratory/photosynthetic electron transport in oxygenic photoautotrophs. Unless effectively scavenged, these ROS can damage all cellular components. The filamentous, heterocystous, nitrogen-fixing strains of the cyanobacterium, Anabaena, serve as naturally abundant contributors of nitrogen biofertilizers in tropical rice paddy fields. Anabaena strains are known to tolerate several abiotic stresses, such as heat, UV, gamma radiation, desiccation, etc., that are known to generate ROS. ROS are detoxified by specific antioxidant enzymes like superoxide dismutases (SOD), catalases and peroxiredoxins. The genome of Anabaena PCC7120 encodes two SODs, two catalases and seven peroxiredoxins, indicating the presence of an elaborate antioxidant enzymatic machinery to defend its cellular components from ROS. This article summarizes recent findings and depicts important perspectives in oxidative stress management in Anabaena PCC7120.

10.
Mar Pollut Bull ; 64(12): 2790-806, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23079701

RESUMO

We used a comparative approach to investigate the impact of the disposal of gold mine tailings into the ocean near the Lihir mine (Niolam Island, Papua New Guinea). We found abundance and diversity of zooplankton, micronekton and pelagic fish to be similar or higher in the mine region compared to the reference site. We also found relatively high trace metal concentrations in lower trophic level groups, especially zooplankton, near the mine discharge, but few differences in tissue concentrations of micronekton, baitfish and pelagic fish between the two regions. Biomagnification of some trace metals by micronekton, and of mercury by fish was evident in both regions. We conclude that ocean mine waste disposal at Niolam Island has a local impact on the smaller and less mobile pelagic communities in terms of trace metal concentrations, but has little effect on the abundance and biodiversity of the local food web.


Assuntos
Ecossistema , Ouro , Mineração , Poluentes Químicos da Água/análise , Zooplâncton/classificação , Animais , Biodiversidade , Monitoramento Ambiental , Peixes/metabolismo , Cadeia Alimentar , Mercúrio/análise , Mercúrio/metabolismo , Metais/análise , Metais/metabolismo , Papua Nova Guiné , Eliminação de Resíduos , Poluentes Químicos da Água/metabolismo , Zooplâncton/crescimento & desenvolvimento , Zooplâncton/metabolismo
11.
Anal Chem ; 84(15): 6672-8, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22881401

RESUMO

A highly sensitive, selective, and rapid, whole-cell-based electrochemical biosensor was developed for detection of the persistent organochlorine pesticide γ-hexachlorocyclohexane (γ-HCH), commonly known as lindane. The gene linA2 encoding the enzyme γ-hexachlorocyclohexane (HCH) dehydrochlorinase (LinA2), involved in the initial steps of lindane (γ-HCH) biotransformation, was cloned and overexpressed in Escherichia coli . The lindane-biodegrading E. coli cells were immobilized on polyaniline film. The rapid and selective degradation of lindane and concomitant generation of hydrochloric acid by the recombinant E. coli cells in the microenvironment of polyaniline led to a change in its conductivity, which was monitored by pulsed amperometry. The biosensor could detect lindane in the part-per-trillion concentration range with a linear response from 2 to 45 ppt. The sensor was found to be selective to all the isomers of hexachlorocyclohexane (HCH) and to pentachlorocyclohexane (PCCH) but did not respond to other aliphatic and aromatic chlorides or to the end product of lindane degradation, i.e., trichlorobenzene (TCB). The sensor also did not respond to other commonly used organochlorine pesticides like DDT and DDE. On the basis of experimental results, a rationale has been proposed for the excellent sensitivity of polyaniline as a pH sensor for detection of H(+) ions released in its microenvironment.


Assuntos
Compostos de Anilina/química , Técnicas Biossensoriais , Técnicas Eletroquímicas , Hexaclorocicloexano/análise , Biodegradação Ambiental , Condutividade Elétrica , Escherichia coli/metabolismo , Hexaclorocicloexano/análogos & derivados , Isomerismo , Praguicidas/análise
12.
Br J Cancer ; 106(12): 1967-75, 2012 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-22596241

RESUMO

BACKGROUND: Carboplatin and cisplatin, alone or in combination with paclitaxel, have similar efficacies against ovarian cancer (OVCA) yet exhibit different toxicity profiles. We characterised the common and unique cellular pathways that underlie OVCA response to these drugs and analyse whether they have a role in OVCA survival. METHODS: Ovarian cancer cell lines (n=36) were treated with carboplatin, cisplatin, paclitaxel, or carboplatin-paclitaxel (CPTX). For each cell line, IC(50) levels were quantified and pre-treatment gene expression analyses were performed. Genes demonstrating expression/IC(50) correlations (measured by Pearson; P<0.01) were subjected to biological pathway analysis. An independent OVCA clinico-genomic data set (n=142) was evaluated for clinical features associated with represented pathways. RESULTS: Cell line sensitivity to carboplatin, cisplatin, paclitaxel, and CPTX was associated with the expression of 77, 68, 64, and 25 biological pathways (P<0.01), respectively. We found three common pathways when drug combinations were compared. Expression of one pathway ('Transcription/CREB pathway') was associated with OVCA overall survival. CONCLUSION: The identification of the Transcription/CREB pathway (associated with OVCA cell line platinum sensitivity and overall survival) could improve patient stratification for treatment with current therapies and the rational selection of future OVCA therapy agents targeted to these pathways.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Carboplatina/administração & dosagem , Linhagem Celular Tumoral/imunologia , Cisplatino/administração & dosagem , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Feminino , Humanos , Neoplasias Ovarianas/mortalidade , Paclitaxel/administração & dosagem , Transdução de Sinais , Resultado do Tratamento
13.
Bioresour Technol ; 116: 290-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22522016

RESUMO

The filamentous, heterocystous, diazotrophic cyanobacterium, Anabaena torulosa was found to bind uranium from aqueous solutions containing 100 µM uranyl carbonate at pH 7.8. The uranyl sequestration kinetics exhibited (a) an initial rapid phase, binding 48% uranium within 30 min resulting in a loading of 56 mg U g(-1) of dry wt, followed by (b) a slower phase, binding 65% uranium with resultant loading of 77.35 mg U g(-1) in 24h. Energy Dispersive X-ray fluorescence spectroscopy of uranium loaded biomass revealed all components of UL X-rays (UL(l), UL(α), UL(ß1) and UL(ß2)). Heat killed cells or extracellular polysaccharides derived from live cells exhibited limited uranyl binding (~26%) highlighting the importance of cell viability for optimum uranyl binding. The present study revealed the involvement of acid soluble polyphosphates in uranium accumulation by this brackish water cyanobacterium.


Assuntos
Anabaena/metabolismo , Fixação de Nitrogênio/fisiologia , Urânio/metabolismo , Ácidos/química , Anabaena/citologia , Biodegradação Ambiental , Temperatura Alta , Viabilidade Microbiana , Polifosfatos/metabolismo , Solubilidade , Urânio/isolamento & purificação
14.
J Microencapsul ; 28(2): 142-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21265713

RESUMO

The aim of this study is to develop ascorbyl palmitate (ASP) loaded doxorubicin (DOX) pegylated liposomes and to evaluate their targeting potential to tumor. We have prepared conventional (DL), pegylated DOX liposomes with (SDL) and without ascorbyl palmitate (SDL-A). The vesicle size in all the formulations was within the range 105-120 nm and in vitro release studies in serum confirmed the stability of the liposomes. Biodistribution studies carried out in Ehrlich ascites tumor bearing mice indicate higher area under the curve for SDL and SDL-A liposomes compared to DL and plain drug solution. Drug targeting index assessed from tumor-to-serum concentration ratio and therapeutic availability of DOX in tumor tissue was also significantly higher for pegylated liposomes. In conclusion, biodistribution study reveals that the presence of ascorbyl palmitate alters the distribution pattern of liposomes and paves way for better drug targeting.


Assuntos
Antibióticos Antineoplásicos , Carcinoma de Ehrlich/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacologia , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/química , Ácido Ascórbico/farmacocinética , Ácido Ascórbico/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Humanos , Lipossomos , Camundongos , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/farmacologia
15.
Osteoarthritis Cartilage ; 18(3): 455-63, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19909832

RESUMO

OBJECTIVE: Glucosamine has been previously shown to suppress cartilage aggrecan catabolism in explant cultures. We determined the effect of glucosamine on ADAMTS5 (a disintegrin-like and metalloprotease domain (reprolysin type) with thrombospondin type-1 motifs 5), a major aggrecanase in osteoarthritis, and investigated a potential mechanism underlying the observed effects. DESIGN: HEK293F and CHO-K1 cells transiently transfected with ADAMTS5 cDNA were treated with glucosamine or the related hexosamine mannosamine. Glucosamine effects on FURIN transcription were determined by quantitative RT-PCR. Effects on furin-mediated processing of ADAMTS5 zymogen, and aggrecan processing by glucosamine-treated cells, were determined by western blotting. Post-translational modification of furin and N-glycan deficient furin mutants generated by site-directed mutagenesis was analyzed by western blotting, and the mutants were evaluated for their ADAMTS5 processing ability in furin-deficient CHO-RPE.40 cells. RESULTS: Ten mM glucosamine and 5-10mM mannosamine reduced excision of the ADAMTS5 propeptide, indicating interference with the propeptide excision mechanism, although mannosamine compromised cell viability at these doses. Although glucosamine had no effect on furin mRNA levels, western blot of furin from glucosamine-treated cells suggested altered post-translational modification. Glucosamine treatment led to decreased glycosylation of cellular furin, with reduced furin autoactivation as the consequence. Recombinant furin treated with peptide N-glycanase F had reduced activity against a synthetic peptide substrate. Indeed, site-directed mutagenesis of two furin N-glycosylation sites, Asn(387) and Asn(440), abrogated furin activation and this mutant was unable to rescue ADAMTS5 processing in furin-deficient cells. CONCLUSIONS: Ten mM glucosamine reduces excision of the ADAMTS5 propeptide via interference with post-translational modification of furin and leads to reduced aggrecanase activity of ADAMTS5.


Assuntos
Proteínas ADAM/efeitos dos fármacos , Furina/efeitos dos fármacos , Glucosamina/metabolismo , Proteína ADAMTS5 , Western Blotting , Células Cultivadas , Humanos , Processamento de Proteína Pós-Traducional , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estatística como Assunto
16.
Bioresour Technol ; 100(7): 2176-81, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19070485

RESUMO

A marine, unicellular cyanobacterium, Synechococcus elongatus strain BDU/75042 was found to sequester uranium from aqueous systems at pH 7.8. The organism could remove 72% (53.5 mg U g(-1) dry weight) of uranium from test solutions containing 100 microM uranyl carbonate within 1h. The equilibrium data fitted well in the Langmuir isotherm thus suggesting a monolayer adsorption of uranium on the cyanobacterial biomass and predicted the maximum adsorption capacity of 124 mg U g(-1) dry weight. Light and scanning electron microscopy coupled with energy dispersive X-ray fluorescence (EDXRF) spectroscopy confirmed the uranyl adsorption by this organism. Most of the bound uranium was found to be associated with the extracellular polysaccharides (EPS) suggesting its interaction with the surface active ligands. Fourier transform infrared (FT-IR) spectroscopy suggested the amide groups and the deprotonated carboxyl groups on the cyanobacterial cell surface were likely to be involved in uranyl adsorption. The cell bound uranium could be released by washing with ethylene diamine tetraacetic acid (EDTA) or 0.1N HCl. The X-ray diffraction (XRD) analyses revealed the identity of uranium deposits associated with the cell biomass as uranyl carbonate hydrate. The study revealed the potential of this cyanobacterium for harvesting uranium from natural aquatic environments.


Assuntos
Água do Mar/microbiologia , Synechococcus/metabolismo , Urânio/isolamento & purificação , Adsorção/efeitos dos fármacos , Biodegradação Ambiental/efeitos dos fármacos , Biomassa , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Synechococcus/citologia , Synechococcus/efeitos dos fármacos , Synechococcus/ultraestrutura , Urânio/farmacologia , Difração de Raios X
17.
J Fish Biol ; 74(7): 1487-98, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-20735648

RESUMO

The biochemical and stress responses of two Indian major carps, rohu Labeo rohita and mrigal Cirrhinus mrigala were studied after acclimating them to four preset temperatures (26, 31, 33 and 36 degrees C) for 30 days. The blood glucose and liver glycogen levels showed an inverse trend in both the species and were significantly different in L. rohita at higher temperatures. The decrease in the liver glycogen level of C. mrigala, however, was not significant. Plasma cortisol levels increased significantly whereas the ascorbic acid content in the brain and kidney of both the species decreased significantly with increasing temperatures. Total lipid content in the liver of both the species decreased significantly with increasing acclimation temperatures. The phospholipid concentration decreased in L. rohita with increasing acclimation temperatures, and in C. mrigala the values decreased up to 33 degrees C and increased at 36 degrees C. In C. mrigala, the cholesterol level decreased up to 33 degrees C and then increased at 36 degrees C, but the absolute value was lower in comparison to L. rohita. The cholesterol levels, however, were not significantly different in L. rohita. Triglycerides and free fatty acids concentrations decreased significantly with increasing acclimation temperatures in both the species. The present study indicates species-specific metabolic responses of L. rohita and C. mrigala to thermal acclimation.


Assuntos
Aclimatação , Cyprinidae/fisiologia , Estresse Fisiológico , Temperatura , Animais , Glicemia/análise , Cyprinidae/metabolismo , Glicogênio Hepático/análise
18.
Mol Ecol ; 16(9): 1897-908, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17444900

RESUMO

Tectonic movement at the boundary of the Indo-Australian and Pacific Plates during the Miocene and Pliocene is recognized as a driving force for invertebrate speciation in New Zealand. Two endemic freshwater crayfish (koura) species, Paranephrops planifrons White 1842 and Paranephrops zealandicus White 1842, represent good model taxa to test geological hypotheses because, due to their low dispersal capacity and life history, geographical restriction of populations may be caused by vicariant processes. Analysis of a mitochondrial DNA marker (cytochrome oxidase subunit I) reveals not two, but three major koura lineages. Contrary to expectation, the cryptic West Coast group appears to be more closely related to P. zealandicus than to P. planifrons and has diverged earlier than the final development (Late Pleistocene) of Cook Strait. Our date estimates suggest that koura lineage diversification probably coincided with early to mid-Alpine orogeny in the mid-Pliocene. Estimates of node ages and the phylogenies are inconsistent with both ancient Oligocene and recent postglacial Pleistocene range expansion, but suggest central to north colonization of North Island and west to east movement in South Island during mid- to late Pliocene. Crypsis and paraphyly of the West Coast group suggest that morphological characters presently used to classify koura species could be misleading.


Assuntos
Astacoidea/genética , Demografia , Especiação Genética , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , Primers do DNA , DNA Mitocondrial/genética , Evolução Molecular , Geografia , Modelos Genéticos , Dados de Sequência Molecular , Nova Zelândia , Análise de Sequência de DNA , Especificidade da Espécie
19.
Tissue Antigens ; 69(4): 293-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17389011

RESUMO

Successful tumour immunity relies on innate and adaptive immune responses, with cytokines like interleukin 4 (IL-4) known to influence tumour clearance in both positive and negative ways. Here, we summarise some of the murine tumour models used over the past two decades to assess the impact of IL-4 on tumour immunity, with emphasis on the effects of IL-4 on the tumour-induced CD8 T-cell response. These data are compared with our own recent studies showing that IL-4 impairs CD8+ T-cell-mediated immunity against the mastocytoma cell line P815 expressing the immunogenic HLA-CW3 gene; moreover, we hypothesise that quantitative and qualitative differences in the HLA-CW3-induced CD8+ T-cell response impair control of tumour growth and aid the development of secondary tumours. We conclude that the duplicitous effects of IL-4 on tumour immunity depend on the type of effector cell (adaptive/innate) mediating tumour clearance and whether tumour growth depends on stromal infrastructure. Thus, the search for factors that improve or weaken the effectiveness of tumour-specific T cells has to be continued to improve modern approaches of immunotherapy against cancer.


Assuntos
Antineoplásicos/farmacologia , Citocinas/metabolismo , Imunoterapia/métodos , Interleucina-4/fisiologia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Animais , Linfócitos T CD8-Positivos/metabolismo , Antígenos HLA-C/genética , Humanos , Camundongos , Camundongos Endogâmicos DBA , Modelos Biológicos , Neoplasias/imunologia , Baço/metabolismo
20.
J Drug Target ; 15(2): 154-61, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17365287

RESUMO

Carbamazepine (CBZ) is used in the treatment of generalized tonic clonic and partial seizures. In seizure disorder the focal point of treatment is brain. At present no commercial parenteral formulation of CBZ is available. We developed o/w nanoemulsions of CBZ stabilized by 1-O-alkylglycerol/lecithin for intravenous administration and evaluated the brain targeting potential of these formulations. The nanoemulsions were characterized for globule size, zeta potential (ZP), CBZ content and in vivo tissue distribution in mice. The in vivo data revealed a significant uptake of CBZ in all tissues. Among the nanoemulsions, 1-O-decylglycerol stabilized system showed significantly higher tissue levels and availability of CBZ. Particularly for this system 2.37 times higher brain availability and a brain/serum concentration ratio of 3.0 at 30 min is an important finding. This indicates the brain targeting potential. A systematic formulation development of CBZ nanoemulsions employing 1-O-alkylglycerols might pave way to achieve selective brain delivery of this important antiepileptic drug.


Assuntos
Anticonvulsivantes/administração & dosagem , Carbamazepina/administração & dosagem , Emulsões , Glicerol/análogos & derivados , Nanotecnologia , Animais , Anticonvulsivantes/farmacocinética , Carbamazepina/farmacocinética , Cromatografia Líquida de Alta Pressão , Glicerol/química , Infusões Intravenosas , Masculino , Camundongos , Distribuição Tecidual
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