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1.
Poult Sci ; 96(9): 3414-3421, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28854741

RESUMO

The freshly ovulated ovum in avian species is surrounded by a protein layer called the inner perivitelline layer (IPVL). The IPVL contains zona pellucida proteins and 6 distinct zona pellucida genes have been identified (ZPA, ZPB1, ZPB2, ZPC, ZPD and ZPX1) in the chicken. In the present research, the expression of the mRNA for ZPA, ZPB2, and ZPX1 was investigated in 2 lines of turkey hens selected for either increased egg production (E line) or increased body weight (F line). Theca and granulosa cell expression of the mRNA for ZPA and ZPB2 was also investigated in hierarchical and prehierarchical follicles from broiler breeder hens. Granulosa tissue was collected from F1 through F4 and F1 through F10 follicles in E line and F line hens, respectively. A one cm2 section of the granulosa layer around the germinal disc (GD) and an equivalent sized nongerminal disc (NGD) area was also collected from the F1 and F2 follicles from other hens from each genetic line. Granulosa and theca tissue was collected from hierarchical and prehierarchical follicles of broiler breeder hens. Total RNA was extracted from the samples. Minor groove-binding probes and primers for detecting ZPA, ZPB2, and ZPX1, were made for real-time PCR analyses. Expression of ZPA, ZPB2, and ZPX1 was detected in all follicle sizes from both genetic lines of hens. No significant differences in ZPA and ZPX1 mRNA expression were detected between the GD and NGD granulosa cells. However, the expression of the mRNA for ZPB2 was significantly greater in the GD granulosa cells when compared to the NGD granulosa cells in F1 and F2 follicles from E line and F line hens. In broiler breeder hens, the mRNA expression of ZPA and ZPB2 was greatest in the smallest prehierarchical follicles. The results suggest that higher expression of ZPB2 in the germinal disc area may be important for the preferential binding of sperm to this region of the IPVL.


Assuntos
Proteínas Aviárias/genética , Expressão Gênica , Perus/genética , Glicoproteínas da Zona Pelúcida/genética , Animais , Proteínas Aviárias/metabolismo , Feminino , Células da Granulosa/metabolismo , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Perus/crescimento & desenvolvimento , Perus/metabolismo , Glicoproteínas da Zona Pelúcida/metabolismo
2.
Talanta ; 151: 100-105, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26946015

RESUMO

The paper reports for the first time the direct determination of silver ion (Ag(+)) using luminescent Carbon Quantum Dot hydrogels (CQDGs). Carbon Quantum Dots (CQDs) with different superficial moieties (passivate-CQDs with carboxylic groups, thiol-CQDs and amine-CQDs) were used to prepare hybrid gels using a low molecular weight hydrogelator (LMWG). The use of the gels results in considerable fluorescence enhancement and also markedly influences selectivity. The most selective CQDG system for Ag(+) ion detection proved to be those containing carboxylic groups onto their surface. The selectivity towards Ag(+) ions is possibly due to its flexible coordination sphere compared with other metal ions. This fluorescent sensing platform is based on the strong Ag-O interaction which can quench the photoluminescence of passivate-CQDs (p-CQDs) through charge transfer. The limit of detection (LOD) and quantification (LOQ) of the proposed method were 0.55 and 1.83µgmL(-1), respectively, being applied in river water samples.

3.
Inorg Chem ; 40(23): 6035-8, 2001 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-11681922

RESUMO

The reaction between GaCl(3) and 1 equiv of HN(SiMe(2)Ph)(2) in CH(2)Cl(2) solution affords colorless crystals of [Cl(2)Ga[mu-N(H)SiMe(2)Ph]](2) (1). The related reaction between GaCl(3) and 1 equiv of LiN(SiMe(2)Ph)(2) in hexane solution results in the isolation of colorless crystals of [PhGa[N(SiMe(2)Ph)(2)](mu-Cl)](2) (2). In contrast, treatment of GaCl(3) with 1 equiv of N(SiMe(3))(3) in CH(2)Cl(2) solutions affords colorless crystals of [MeGaCl(2)](2) (4). Compounds 2 and 4 are the result of monochloride substitution and transfer of a phenyl and methyl ligand, respectively, from the silyl group of the amine to the Ga center. All the complexes have been characterized by X-ray crystallography.

4.
Org Lett ; 3(22): 3565-8, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11678709

RESUMO

[reaction: see text]. Trisulfide 2-oxide 11 has been prepared from disulfide 9 via reduction to the corresponding dithiol and subsequent trapping with thionyl chloride. Heating trisulfide oxide 11 in the presence of dienes results in transfer of sulfur monoxide to form cyclic unsaturated sulfoxides 13 in good to excellent yields, along with recovery of disulfide 9. A Pummerer reaction can be used to convert the cyclic sulfoxides into thiophenes.

5.
Inorg Chem ; 40(19): 4978-85, 2001 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-11531447

RESUMO

The preparation and structures of a variety of oxonium ion tetrachloroaurate(III) salts isolated from aqua regia are reported. The new compounds are [(H(5)O(2))(2)(12-crown-4)(2)][AuCl(4)](2) (1), [(H(7)O(3))(15-crown-5)][AuCl(4)] (2), [(H(5)O(2))(benzo-15-crown-5)(2)][AuCl(4)] (3), [(H(3)O)(18-crown-6)][AuCl(4)] (4), [(H(5)O(2))(dibenzo-24-crown-8)][AuCl(4)] (5), [(H(5)O(2))(4-nitrobenzo-15-crown-5)(2)][AuCl(4)] (6), [(H(3)O)(4-nitrobenzo-18-crown-6)][AuCl(4)] (7), [(H(11)O(5))(tetrachlorodibenzo-18-crown-6)(2)][AuCl(4)] (8), and [(H(7)O(3))(dinitrodibenzo-30-crown-10)][AuCl(4)] (9). A significant correlation between the degree of proton hydration and crown ether size is observed. Aryl crown ethers are nitrated in concentrated aqua regia, but nonnitrated products may be obtained in a dilute solution of aqua regia by reaction with aqueous HAuCl(4).

6.
Inorg Chem ; 40(17): 4384-8, 2001 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-11487346

RESUMO

Zinc(II) and tin(II) derivatives of maltol (Hmalt), ethylmaltol (HEtmalt), tropolone (Htrop), hinokitiol (Hhino), and kojic acid (Hkoj) have been prepared and characterized, and the crystal structures of M(trop)(2) (M = Zn, Sn), Zn(hino)(2).EtOH, and Sn(malt)(2) have been determined. The Zn(trop)(2) is a polymeric structure in which tropolone has both a bridging and chelating role; zinc(hino)(2) crystallizes as an ethanol adduct of which the structure is a dimeric fragment of the Zn(trop)(2) polymer and in which each metal is "capped" by a molecule of alcohol. The tin complexes are notably air-stable despite adopting monomeric pseudo-trigonal-bipyramidal structures (SnO(4)E; E is a stereochemically active lone electron pair) in which the ligands only chelate a single metal center.

8.
Acta Crystallogr C ; 57(Pt 6): 670-1, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11408664

RESUMO

The title compound, catena-poly[dihydraziniochromium(II)-di-mu-sulfato-O:O'], [Cr(N2H5)2(SO4)2], was studied at 100 K and contains chains of chromium(II) ions linked by pairs of sulfate anions and coordinated to hydrazinium ions. The unique Cr atom lies on an inversion centre. All five H atoms were experimentally located and are involved in hydrogen bonding to O atoms of the sulfate groups.

9.
Biophys J ; 80(5): 2133-9, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11325716

RESUMO

Fluorescent Ca2+ probes and digital photo-sectioning techniques were used to directly study the dynamics of Ca2+ in isolated mast cell granules of normal (CB/J) and beige (Bg(j)/Bg(j)) mice. The resting intraluminal free Ca2+ concentration ([Ca2+]L) is 25 +/- 4.2 microM (mean +/- SD, n = 68). Exposure to 3 microM inositol 1,4,5-trisphosphate (InsP3) induced periodic oscillations of luminal Ca2+ ([Ca2+]L) of approximately 10 microM amplitude and a period around 8-10 s. The [Ca2+]L oscillations were accompanied by a corresponding oscillatory release of [Ca2+]L to the extraluminal space. Control experiments using ruthenium red (2 microM) and thapsigargin (100 nM) ruled out artifacts derived from the eventual presence of mitochondria or endoplasmic reticulum in the isolated granule preparation. Oscillations of [Ca2+]L and Ca2+ release result from a Ca2+/K+ exchange process whereby bound Ca is displaced from the heparin polyanionic matrix by inflow of K+ into the granular lumen via an apamin-sensitive Ca2+-sensitive K+ channel (ASK(Ca)), whereas Ca2+ release takes place via an InsP3-receptor-Ca2+ (InsP3-R) channel. These results are consistent with previous observations of [Ca2+]L oscillations and release in/from the endoplasmic reticulum and mucin granules, and suggest that a highly conserved common mechanism might be responsible for [Ca2+]L oscillations and quantal periodic Ca2+ release in/from intracellular Ca2+ storage compartments.


Assuntos
Cálcio/metabolismo , Íons , Mastócitos/química , Vesículas Secretórias/química , Animais , Fenômenos Biofísicos , Biofísica , Relação Dose-Resposta a Droga , Inositol 1,4,5-Trifosfato/metabolismo , Troca Iônica , Camundongos , Modelos Biológicos , Potássio/metabolismo , Rutênio Vermelho/farmacologia , Transdução de Sinais , Espectrometria de Fluorescência , Tapsigargina/farmacologia , Fatores de Tempo
10.
Chemistry ; 7(6): 1240-7, 2001 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-11322550

RESUMO

Reaction of [15]crown-5 with erbium nitrate and a range of nickel salts results in the formation of the hydrogen-bonded chain species [Er(NO3)3(H2O)3]. [15]crown-5 H2O (3), [Ni(H2O)6]Br2 [15]crown-5 2H2O (4), [Ni(H2O)6](ClO4)2 x [15]crown-5 2H2O (5), [Ni(H2O)6](NO3)2 [15]crown-5 2H2O (6) and [[Ni(H2O)4]2(muCl)2]Cl2 [15]crown-5 (7). Complexes 3-5 exhibit low symmetry structures with 2-4 unique crown ether molecules, whereas 6 and 7 are more symmetrical. The factors contributing to this behaviour are discussed within the wider context of [15]crown-5 structures in the Cambridge Structural Database.

12.
Can Assoc Radiol J ; 48(3): 186-90, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9193418

RESUMO

OBJECTIVE: To determine if the adequacy of freezing in the neurovascular bundle region of the prostate during prostate cryotherapy can be monitored by transrectal ultrasonography (TRUS). PATIENTS AND METHODS: The study group consisted of 11 patients undergoing TRUS-guided prostate cryotherapy. The actual temperature in the gland was monitored with thermosensors placed in each prostatic neurovascular bundle. The 2 cryo-operators, working together and blinded to the actual temperature, used sonographic observations to estimate the temperature at the neurovascular bundles every 2 minutes until they believed that the gland was adequately frozen. The congruity between the estimated and measured temperatures was analyzed to determine if the operators could accurately monitor the progress of cryoablation by ultrasonography. RESULTS: There were a total of 85 data points for which the operators thought tumoricidal cryo-injury had been achieved at the neurovascular bundles (temperature -20 degrees C or below). For these points the measured temperature was on average 6.0 degrees C warmer than the estimated temperature (standard deviation, 22). For operator estimates of -20 degrees C or below, the measured temperature was -20 degrees C or below for 37 (44%) data points, between -19 degrees C and 0 degree C for 32 (38%) and greater than 0 degree C for 16 (19%). CONCLUSIONS: The operators were not able to accurately predict subzero temperatures at the neurovascular bundle region by TRUS evaluation. Moreover, the bias and magnitude of the error were significant and might lead to inadequate freezing of the prostate during attempted cryoablation.


Assuntos
Temperatura Corporal , Criocirurgia , Próstata/diagnóstico por imagem , Prostatectomia , Neoplasias da Próstata/cirurgia , Termômetros , Ultrassonografia de Intervenção , Previsões , Congelamento , Humanos , Masculino , Monitorização Intraoperatória , Variações Dependentes do Observador , Estudos Prospectivos , Próstata/irrigação sanguínea , Próstata/inervação , Próstata/fisiopatologia , Reto , Método Simples-Cego
13.
Med Sci Sports Exerc ; 26(6): 797-803, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8052120

RESUMO

We examined whether the relation between of ratings of perceived exertion (RPE) and exercise intensities associated with the lactate threshold (LT) and blood lactate concentrations (BLC) of 2.5 and 4.0 mM, established with an incremental protocol, held during 30-min treadmill run at constant velocity (V). RPE (11.6, 14.9, 16.8, 18.9), oxygen uptake (VO2) (3.2, 3.7, 3.9, 4.2 l.min-1), and V (168, 196, 215, 227 m.min-1) at LT, BLC of 2.5, and 4.0 mM and peak were determined for nine males during incremental exercise. Subjects then completed three 30-min runs at the V associated with LT and BLC of 2.5 and 4.0 mM, with RPE, VO2, and blood [HLa] determined every 5 min. After min 10 during the 30-min runs, RPE, VO2, and BLC were not significantly different from corresponding values observed during the incremental protocol. Regression equations predicting BLC from RPE were generated from results obtained during the incremental protocol. RPE values from the 30-min runs were used to predict BLC, and the measured BLC was used to validate the use of RPE as a predictor of BLC. Correlations ranged from r = 0.79 to r = 0.98 [total error (TE) ranged from 0.6-1.3 mM]. We conclude that RPE is a physiologically valid tool for prescribing exercise intensity when the intent is to use LT and/or BLC as the intensity criterion.


Assuntos
Lactatos/sangue , Esforço Físico/fisiologia , Corrida/fisiologia , Adulto , Análise de Variância , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia
14.
J Bacteriol ; 141(3): 1284-90, 1980 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6988412

RESUMO

We analyzed a series of germ tube-negative variants isolated from Candida albicans 3153A for deoxyribonucleic acid content. As analyzed by flow microfluorometry, the deoxyribonucleic acid level in these variant strains was 50% of that of the parental strain and equivalent to that of haploid Saccharomyces cerevisiae. This finding was confirmed by comparison of survival rates when exposed to the mutagens ultraviolet light, ethyl methane sulfonate, and methyl methane sulfonate. The diameter of the variant cells as compared to the diameter of the parental 3153A strain showed a relationship similar to that of the diameters of haploid versus diploid S. cerevisiae. These results indicate that those strains may be representative of the imperfect stage of C. albicans.


Assuntos
Candida albicans/análise , DNA Fúngico/análise , Candida albicans/citologia , Candida albicans/efeitos dos fármacos , Metanossulfonato de Etila/farmacologia , Haploidia , Interfase , Metanossulfonato de Metila/farmacologia , Espectrometria de Fluorescência , Raios Ultravioleta
15.
J Ark Med Soc ; 67(10): 329-31, 1971 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-4251615
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