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1.
Langmuir ; 32(34): 8631-40, 2016 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-27487358

RESUMO

Intrusion of a liquid droplet into a hexagonal close-packed array of spheres under gravity is investigated using analytical methods and volume-of-fluid simulations. Four regimes of ultimate fluid behavior are identified: (A) no liquid imbibition into the bed, (B) trapping of liquid high in the bed, (C) liquid descending to the bottom of the bed, and (D) liquid spreading around the surface of all particles. These regimes are mapped based on the contact angle and Bond number of the system. Many aspects of the dynamics and ultimate liquid behavior are captured using a simplified model of a mass of liquid moving under gravity in a vertical capillary of undulating cross-sectional area. This simplified model is used to form momentum transport equations with four forms of nondimensional time, which are shown to collapse the simulation data with different fluid parameters in different regimes.

2.
Neuroscience ; 312: 165-78, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26592716

RESUMO

Afferent connections to the sensory inner (IHCs) and outer hair cells (OHCs) in the cochlea refine and functionally mature during the thyroid hormone (TH)-critical period of inner ear development that occurs perinatally in rodents. In this study, we investigated the effects of hypothyroidism on afferent type II innervation to outer hair cells using the Snell dwarf mouse (Pit1(dw)). Using a transgenic approach to specifically label type II spiral ganglion neurons (SGNs), we found that lack of TH causes persistence of excess type II SGN connections to the OHCs, as well as continued expression of the hair cell functional marker, otoferlin (OTOF), in the OHCs beyond the maturation period. We also observed a concurrent delay in efferent attachment to the OHCs. Supplementing with TH during the early postnatal period from postnatal day (P) 3 to P4 reversed the defect in type II SGN pruning but did not alter OTOF expression. Our results show that hypothyroidism causes a defect in the large-scale pruning of afferent type II SGNs in the cochlea, and a delay in efferent attachment and the maturation of OTOF expression. Our data suggest that the state of maturation of hair cells, as determined by OTOF expression, may not regulate the pruning of their afferent innervation.


Assuntos
Células Ciliadas Auditivas Externas/metabolismo , Hipotireoidismo/metabolismo , Proteínas de Membrana/metabolismo , Plasticidade Neuronal/fisiologia , Gânglio Espiral da Cóclea/metabolismo , Tri-Iodotironina/farmacologia , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Células Ciliadas Auditivas Externas/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Plasticidade Neuronal/efeitos dos fármacos , Tri-Iodotironina/administração & dosagem
3.
Hum Exp Toxicol ; 35(6): 685-92, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26251508

RESUMO

INTRODUCTION: Chemoprevention may involve perturbation of a variety of steps in tumor initiation, promotion, and progression. OBJECTIVE: To investigate the antiproliferative and anti-inflammatory potential effects of diindolylmethane (DIM) and lupeol on experimental bladder carcinogenesis. METHODS: Sixty healthy male Wistar rats were selected and randomly divided into six groups, with 10 rats in each group. Group I: control; group II: N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN; 150 mg/gavage/twice a week) for 8 weeks, and then they were given 100 ppm concentrations of dimethylarsenic acid (DMA) in the drinking water for 28 weeks; group III: BBN + DMA + DIM (5 mg/kg body weight (b.w.)/day) treatment was started after BBN treatment, and it was orally administered for 28 weeks); group IV: BBN + DMA + lupeol (50 mg/kg b.w./day) treatment was started after BBN treatment, and it was orally administered for 28 weeks); and groups V and VI: DIM and lupeol treatment alone for 36 weeks. Bladder tissues were collected after 36th week study protocol for further analysis. RESULTS: Our results revealed that DIM and lupeol treatment showed inhibition of tumor growth in the bladder by histopathological confirmations as well as significantly (p < 0.001) increased the expression of phosphotensin (PTEN) and significantly (p < 0.001) decreased the expression of tumor necrosis factor α, nuclear factor κß (p65) were quantified using Western blot analysis. DIM and lupeol treatment significantly (p < 0.001) decreased the levels of Cox-2 in bladder tissue samples and NMP 22 in urine samples were quantified using enzyme-linked immunosorbent assay method. CONCLUSION: Preventive DIM and lupeol administration act as potent Cox-2 inhibitors, which activates the tumor suppressor protein PTEN against experimental bladder carcinogenesis by antiproliferative and anti-inflammatory properties.


Assuntos
Antineoplásicos/uso terapêutico , Butilidroxibutilnitrosamina/toxicidade , Proliferação de Células/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Indóis/uso terapêutico , Triterpenos Pentacíclicos/uso terapêutico , Neoplasias da Bexiga Urinária/prevenção & controle , Animais , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/urina , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Indóis/administração & dosagem , Masculino , Proteínas Nucleares/urina , PTEN Fosfo-Hidrolase/metabolismo , Triterpenos Pentacíclicos/administração & dosagem , Ratos Wistar , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/patologia
5.
Curr Oncol ; 21(1): 27-34, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24523602

RESUMO

BACKGROUND: Patients requiring assessment for cancer surgery encounter a complex series of steps in their cancer journey. Further complicating the process is the fact that care is often delivered in a fragmented, silo-based system. Isolated strategies to improve cancer outcomes within those systems have had inconsistent results. METHODS: A regional quality improvement collaborative was developed based on a community of practice (cop) platform, a hub-and-spoke infrastructure, and a regional steering committee linking cop improvement projects with affiliated hospitals and their strategic priorities. The cop provided an avenue for multidisciplinary teams to collect and compare their performance data and to institute regional standards through literature review, discussion, and consensus. Regional interdisciplinary teams developed a set of quality indicators linked to mutually agreed-upon care standards. A limited regional database supported feedback about performance against both provincial and regional standards. RESULTS: The cop approach helped to develop a multihospital collaboration that facilitated care quality improvements on a regional scale, with clinical outcomes of the improvements able to be measured. The 9 participating hospitals delivered cancer surgery in the specific disease sites according to practitioner-developed and provincially- or regionally-generated care standards and clinical pathways. Compliance with provincial evidence-based clinical guidelines improved (20% increase in 2010-2011 compared with 2006-2007). Other significant improvements included standardization and implementation of regional perioperative pathways in breast, colorectal, and prostate cancer disease sites; rectal cancer surgery centralization; increased use of sentinel lymph node biopsies in breast cancer surgery; and decreased positive surgical margin rates in prostate cancer. CONCLUSIONS: Improved quality is likely a result of diverse confounding factors. The deliberately cultivated multihospital multidisciplinary cops have contributed to positive structural and functional change in cancer surgery in the region. This regional cop model has the potential to play an important role in the development of successful collaborations in care quality improvement.

6.
J Synchrotron Radiat ; 20(Pt 6): 843-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24121325

RESUMO

Haemoglobin (Hb) is a tetrameric iron-containing protein that carries oxygen from the lungs to tissues and carbon dioxide from tissues back to the lungs. Pisces are the advanced aquatic vertebrates capable of surviving at wide depth ranges. The shortfin mako shark (SMS) is the pelagic, largest, fastest and most sophisticated species of the shark kingdom with well developed eyes. Mostly the pisces species are cold blooded in nature. Distinctly, the SMSs are warm-blooded animals with an advanced circulatory system. SMSs are capable of maintaining elevated muscle temperatures up to 33 K above the ambient water temperatures at a depth of 150-500 m. SMSs have a diverged air-breathing mechanism compared with other vertebrates. The haemoglobin molecule consists of four polypeptide chains, namely two α chains, each with 140 amino acids and two ß chains each having 136 amino acids. The SMS Hb was found to crystallize in monoclinic space group P21 using the hanging-drop vapour-diffusion method at room temperature. The crystal packing parameters for the SMS Hb structure contain one whole biological molecule in the asymmetric unit with a solvent content of 47%. The SMS Hb quaternary structural features interface-interface interactions and heme binding sites are discussed with different state Hbs and the results reveal that SMS Hb adopts an unliganded deoxy T state conformation.


Assuntos
Hemoglobinas/química , Tubarões , Animais , Modelos Moleculares , Conformação Proteica
9.
Curr Oncol ; 17(3): 70-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20651901

RESUMO

The annual Eastern Canadian Colorectal Cancer Consensus Conference was held in Montreal, Quebec, October 22-24, 2009. Health care professionals involved in the care of patients with colorectal cancer participated in presentation and discussion sessions for the purposes of developing the recommendations presented here. This consensus statement addresses current issues in the management colorectal cancer, such as the management of hepatic and pulmonary metastases, the role of monoclonal antibodies to the epidermal growth factor receptor, and the benefits and safety of chemotherapy in elderly patients. The management of gastrointestinal neuroendocrine tumours and gastric cancer are also discussed.

10.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 3): o646, 2010 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-21580400

RESUMO

In the title mol-ecule, C(37)H(35)N(3)O(6), the pyrrolidine ring adopts a twist conformation and the piperidine ring is in a distorted boat conformation. One of the phenyl rings is disordered over two positions with occupancies of 0.54 (2) and 0.46 (2) and the ethyl carboxyl-ate group is also disordered over two orientations with occupancies of 0.75 (1) and 0.25 (1).

11.
Artigo em Inglês | MEDLINE | ID: mdl-19574638

RESUMO

Haemoglobin is a tetrameric protein that carries oxygen from the lungs to tissues and carbon dioxide from tissues back to the lungs. The oxygen-binding properties of haemoglobin are regulated through the binding of allosteric effectors. The respiratory system of avian species is unique and complex in nature when compared with that of mammals. In avian species, inositol pentaphosphate (inositol-P(5)) is present in the erythrocytes of the adult and is thought to be the major factor responsible for the relatively high oxygen affinity of the whole blood. The ostrich (Struthio camelus) is a large flightless bird which contains inositol tetrakisphosphate (inositol-P(4)) in its erythrocytes and its whole blood oxygen affinity is higher. Efforts have been made to explore the structure-function relationship of ostrich haemoglobin. Ostrich haemoglobin was purified using ion-exchange chromatography. Haemoglobin crystals were grown by the hanging-drop vapour-diffusion method using PEG 3350 as the precipitant in 50 mM phosphate buffer pH 7.2. Data were collected using a MAR345 image-plate detector system. The crystals of ostrich haemoglobin diffracted to 2.2 A resolution. They belonged to the orthorhombic space group P2(1)2(1)2(1) with one whole biological molecule in the asymmetric unit; the unit-cell parameters were a = 80.93, b = 81.68, c = 102.05 A.


Assuntos
Hemoglobinas/química , Hemoglobinas/isolamento & purificação , Struthioniformes , Animais , Cristalização , Cristalografia por Raios X
12.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): o1945, 2009 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21583626

RESUMO

In the title compound, C(21)H(15)N(5)O(2), the pyrrolidine ring adopts a twist conformation. Both the oxindole rings are planar [maximum deviations of 0.076 (1) and 0.029 (1) Šin the two rings] and are oriented at a dihedral angle of 72.7 (1)°. The crystal structure is stabilized by C-H⋯O, N-H⋯O, N-H⋯N and C-H⋯π inter-actions.

13.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 5): o994, 2009 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21584029

RESUMO

In the title compound, C(23)H(18)N(2)O(4)·H(2)O, the two oxindole rings subtend a dihedral angle of 54.29 (5)°. The crystal structure is stabilized by intermolecular N-H⋯O, O-H⋯O and C-H⋯π inter-actions.

14.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 5): o995, 2009 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21584030

RESUMO

There are two independent mol-ecules in the asymmetric unit of the title compound, C(18)H(12)ClN(3)O. The two pyridine rings are almost coplanar [dihedral angles between the rings: 2.87 (15) and 5.36 (16)°] while the chloro-phenyl rings are twisted out of the plane of the adjacent bipyridine ring by 44.1 (1) and 43.8 (1)° in the two mol-ecules. The crystal packing is stabilized by C-H⋯N and C-H⋯Cl inter-actions.

15.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 5): o996-7, 2009 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21584031

RESUMO

The title compound, C(25)H(14)Cl(2)N(4), crystallizes with two independent mol-ecules in the asymmetric unit. The two pyridine rings are almost coplanar, making dihedral angles of 3.2 (1) and 8.6 (1)° in the two independent mol-ecules. The dichloro-phenyl and indole rings are twisted away from the bipyridine ring by 64.32 (5) and 18.46 (4)°, respectively in the first molecule and by 51.0 (1) and 27.99 (5)°, respectively in the second molecule. The crystal packing is stabilized by C-H⋯N, C-H⋯Cl, N-H⋯N and C-H⋯π inter-actions.

16.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 11): o2881-2, 2009 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-21578467

RESUMO

In the title compound, C(31)H(24)Cl(2)N(2)S(2), the pyrazole ring adopts planar conformation with a maximum deviation of 0.002 (2) Å. The chloro-phenyl rings are twisted out of the plane of the pyrazole ring by 75.1 (1) and 39.5 (1)°. The crystal packing is controlled by weak intermolecular C-H⋯π interactions.

17.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 10): o1993, 2008 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-21201192

RESUMO

In the title mol-ecule, C(35)H(33)N(3)O(6), the pyrrolidine ring adopts a twist conformation. The mol-ecules are paired into centrosymmetric dimers by weak inter-molecular C-H⋯O hydrogen bonds. The dimers inter-act further again via C-H⋯O hydrogen bonds and N-H⋯O intramolecular interaction also stabilize the crystal packing.

18.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 10): o2042, 2008 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21201234

RESUMO

In the title compound, C(37)H(34)ClN(3)O(6), the pyrrolidine and piperidine rings adopt envelope and boat conformations, respectively. The ß-lactam ring is planar and forms dihedral angles of 21.3 (2) and 73.9 (2)°, respectively, with the attached methoxy-phenyl and phenyl rings. Intra-molecular C-H⋯O and C-H⋯N hydrogen bonds are observed. Centrosym-metrically related mol-ecules are linked together by weak C-H⋯O hydrogen bonds to form dimers.

19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(5 Pt 1): 051309, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17677056

RESUMO

We use an "equation-free," coarse-grained computational approach to accelerate molecular dynamics-based computations of demixing (segregation) of dissimilar particles subject to an upward gas flow (gas-fluidized beds). We explore the coarse-grained dynamics of these phenomena in gently fluidized beds of solid mixtures of different densities, typically a slow process for which reasonable continuum models are currently unavailable.

20.
J Ethnopharmacol ; 99(1): 147-51, 2005 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-15848035

RESUMO

The antimicrobial activity of extracts of Curcuma zedoaria and Curcuma malabarica tubers was tested against six bacterial and two fungal strains using the agar well diffusion and broth dilution methods. Petroleum ether, hexane, chloroform, acetone and ethanol extracts exhibited antibacterial as well as antifungal activity. Acetone and hexane extracts of both tubers showed comparable antimicrobial activity as indicated by minimum inhibitory concentration (MIC) values, but other extracts of Curcuma malabarica showed significantly lower activity than those of Curcuma zedoaria. The MIC values for different strains and extracts ranged from 0.01 to 0.15 mg/ml in Curcuma zedoaria and from 0.01 to 0.94 mg/ml in Curcuma malabarica. Staphylococcus aureus (Gram positive) was inhibited by Curcuma malabarica but not by Curcuma zedoaria. This study is the first report of the antimicrobial properties of Curcuma malabarica. The findings also support the use of Curcuma zedoaria tubers in traditional medicine for the treatment of bacterial and fungal infections.


Assuntos
Anti-Infecciosos/farmacologia , Curcuma/química , Tubérculos/química , Anti-Infecciosos/isolamento & purificação , Bactérias/efeitos dos fármacos , Meios de Cultura , Fungos/efeitos dos fármacos , Medicina Tradicional , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia
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