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1.
J Dairy Sci ; 96(7): 4436-46, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23660147

RESUMEN

The objectives of the current experiment were to determine the effect of 2 prepartum grouping strategies on the health, metabolic, reproductive, and productive parameters of dairy cows. Jersey cows enrolled in the experiment at 253±3 d of gestation (d 0=calving) were balanced for parity and projected 305-d mature equivalent and assigned to 1 of 2 treatments. Cows assigned to the traditional (TRD; n=6 replicates with a total of 308 cows) treatment were moved to the study pen as a group of 44 cows and weekly thereafter groups of 2 to 15 cows were moved to the study pen to reestablish stocking density. Cows assigned to the all-in-all-out (AIAO; n=6 replicates with a total of 259 cows) treatment were moved to the study pen in groups of 44 cows, but no new cows entered the AIAO pen until the end of the replicate. At the end of each replicate, a new TRD and AIAO group started but pens were switched. Cows were milked thrice daily and monthly milk yield, fat and protein contents, and somatic cell count data were recorded up to 305 d postpartum. Plasma nonesterified fatty acid concentration was measured weekly from d -18±3 to 24±3 and plasma ß-hydroxybutyrate was measured weekly from d 3±3 to 24±3. Cows were examined on d 1, 4±1, 7±1, 10±1, and 13±1 for diagnosis of uterine diseases and had their ovaries scanned by ultrasound on d 39±3 and 53±3 to determine resumption of ovarian cycles. Average stocking density was reduced for the AIAO (71.9%) treatment compared with the TRD (86.9%) treatment. Treatment did not affect the incidences of retained fetal membranes (TRD=10.9, AIAO=11.6%), metritis (TRD=16.7, AIAO=19.8%), and acute metritis (TRD=1.7, AIAO=3.6%). Concentrations of nonesterified fatty acids (TRD=80.4±8.2, AIAO=62.9±8.5 µmol/L) and ß-hydroxybutyrate (TRD=454.4±10.9, AIAO=446.1±11.1 µmol/L) were not different between treatments. Percentages of cows that resumed ovarian cycles by d 39±3 (TRD=70.8, AIAO=63.1%) and 53±3 (TRD=90.1, AIAO=90.2%) were not different between treatments. Similarly, treatment had no effect on rate of removal from the herd {TRD=referent, AIAO [(adjusted hazard ratio (95% confidence interval)]=0.85 (0.63, 1.15)} or rate of pregnancy [TRD=referent, AIAO=1.07 (0.88, 1.30)]. Finally, treatment did not affect energy-corrected milk yield (TRD=34.4±0.6, AIAO=34.3±0.7 kg/d). In conditions of adequate feed bunk space, the AIAO treatment did not improve health, metabolic, reproductive, or productive parameters compared with the TRD treatment.


Asunto(s)
Conducta Animal/fisiología , Bovinos/fisiología , Industria Lechera/métodos , Estado de Salud , Reproducción/fisiología , Conducta Social , Ácido 3-Hidroxibutírico/sangre , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal , Enfermedades de los Bovinos/epidemiología , Recuento de Células , Grasas/análisis , Ácidos Grasos no Esterificados/sangre , Femenino , Edad Gestacional , Lactancia , Leche/química , Leche/citología , Proteínas de la Leche/análisis , Ovario/diagnóstico por imagen , Embarazo , Trastornos Puerperales/epidemiología , Trastornos Puerperales/veterinaria , Ultrasonografía
2.
J Dairy Sci ; 96(12): 7649-57, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24140318

RESUMEN

Objectives were to evaluate the effects of a stable prepartum grouping strategy on innate immune parameters, antibody concentration, and cortisol and haptoglobin concentrations of Jersey cows. Cows (253±3 d of gestation) were paired by gestation length and assigned randomly to the stable (all-in-all-out; AIAO) or traditional (TRD) treatment. In the AIAO treatment, groups of 44 cows were moved into a pen where they remained for 5 wk, whereas in the TRD treatment, approximately 10 cows were moved into a pen weekly to maintain stocking density (44 cows for 48 headlocks). Pens were identical in size and design and each pen received each treatment a total of 3 times (6 replicates; AIAO, n=259; TRD, n=308). A subgroup of cows (n=34/treatment) was selected on wk 1 of each replicate from which blood was sampled weekly from d -14 to 14 (d 0=calving) to determine polymorphonuclear leukocyte (PMNL) phagocytosis, oxidative burst, and expression of CD18 and L-selectin, hemogram, cortisol and glucose concentrations, and haptoglobin concentration. Another subgroup of cows (n=40/treatment) selected on wk 1 of each replicate was treated with chicken egg ovalbumin on d -21, -7, and 7 and had blood sampled weekly from d -21 to 21 for determination of immunoglobulin G anti-ovalbumin. All cows (n=149) had blood sampled weekly for nonesterified fatty acid (NEFA) and ß-hydroxybutyrate (BHBA) concentrations from d -21 to 21. Treatment did not affect percentage of PMNL positive for phagocytosis and oxidative burst (AIAO=64.3±2.9 vs. TRD=64.3±2.9%) and intensity of phagocytosis [AIAO=2,910.82±405.99 vs. TRD=2,981.52±406.87 geometric mean fluorescence intensity (GMFI)] and oxidative burst (AIAO=7,667.99±678.29 vs. TRD=7,742.70±682.91 GMFI). Similarly, treatment did not affect the percentage of PMNL expressing CD18 (AIAO=96.3±0.7 vs. TRD=97.8±0.7%) and L-selectin (AIAO=44.1±2.8 vs. TRD=45.1±2.8%) or the intensity of expression of CD18 (AIAO=3,496.2±396.5 vs. TRD=3,598.5±396.9 GMFI) and L-selectin (AIAO=949.8±22.0 vs. TRD=940.4±22.3 GMFI). Concentration of immunoglobulin G anti-ovalbumin was not affected by treatment (AIAO=0.98±0.05 vs. TRD=0.98±0.05 OD). The percentage of leukocytes classified as granulocyte (AIAO=38.9±1.5 vs. TRD 38.2±1.5%) and the granulocyte:lymphocyte ratio (AIAO=0.75±0.04 vs. TRD=0.75±0.04) were not affected by treatment. Concentrations of cortisol (AIAO=14.95±1.73 vs. TRD=18.07±1.73 ng/mL), glucose (AIAO=57.6±1.5 vs. TRD=60.0±1.5 ng/mL), and haptoglobin (AIAO=3.09±0.48 vs. TRD=3.51±0.49 OD) were not affected by treatment. According to the current experiment, a stable prepartum grouping strategy does not improve innate immune parameters or antibody concentration compared with weekly prepartum regrouping.


Asunto(s)
Ácido 3-Hidroxibutírico , Inmunidad Innata , Ácido 3-Hidroxibutírico/sangre , Animales , Anticuerpos , Bovinos , Ácidos Grasos no Esterificados/sangre , Femenino , Selectina L , Lactancia
3.
Toxicol Lett ; 293: 9-15, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29702200

RESUMEN

In August 2003, 44 victims were poisoned by chemical warfare agents (CWAs) leaked from five drums that were excavated at a construction site in Qiqihar, Northeast China. The drums were abandoned by the former Japanese imperial army during World War II and contained a mixture of Sulfur mustard (SM) and Lewisite. We carried out a total of six regular check-ups between 2006 and 2014, and from 2008 we added neurological evaluations including neuropsychological test and autonomic nervous function test in parallel with medical follow-up as much as was possible. Severe autonomic failure, such as hyperhidrosis, pollakiuria, diarrhoea, diminished libido, and asthenia appeared in almost all victims. Polyneuropathy occurred in 35% of the victims and constricted vision occurred in 20% of them. The rates of abnormal response on cold pressor test (CPT), active standing test (AST), Heart rate variability (CVR-R), performed in 2014, were 63.1%, 31.6%, and 15.9%, respectively. On neuropsychological testing evaluated in 2010, a generalized cognitive decline was observed in 42% of the victims. Memories and visuospatial abilities were affected in the remaining victims. Finally, a 17-item PTSD questionnaire and the Beck Depression Inventory evaluated in 2014 revealed long-lasting severe PTSD symptoms and depression of the victims. Our findings suggest that an SM/Lewisite compound have significant adverse consequences directly in cognitive and emotional network and autonomic nervous systems in the brain.


Asunto(s)
Intoxicación por Arsénico/historia , Arsenicales , Sustancias para la Guerra Química/envenenamiento , Guerra Química/psicología , Trastornos Mentales/inducido químicamente , Trastornos Mentales/psicología , Gas Mostaza/envenenamiento , Enfermedades del Sistema Nervioso/inducido químicamente , Enfermedades del Sistema Nervioso/psicología , Segunda Guerra Mundial , Adulto , Arsenicales/historia , Pueblo Asiatico , Enfermedades del Sistema Nervioso Autónomo/inducido químicamente , Guerra Química/historia , Sustancias para la Guerra Química/historia , China , Femenino , Historia del Siglo XX , Humanos , Masculino , Persona de Mediana Edad , Fuerza Muscular/efectos de los fármacos , Gas Mostaza/historia , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Trastornos por Estrés Postraumático/psicología , Adulto Joven
4.
Water Sci Technol ; 55(7): 203-10, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17506439

RESUMEN

The aim of this study was to examine the relationship between ammonia oxidizing bacterial populations and biological nitrogen removal in a small on-site domestic wastewater treatment system "Johkasou". The population dynamics of ammonia oxidizing bacteria (AOB) in six full-scale advanced Johkasous was surveyed using real-time PCR assay over a period of one year. These Johkasous were selected to compare the AOB populations in different treatment performance. When the effluent NH4-N concentration was higher than 2 mg L(-1), it was difficult to meet the effluent standard of advanced Johkasous (T-N 10 mg L(-1)). In contrast, the nitrogen removal efficiency was hardly affected by nitrite oxidation and denitrification in these systems. In other words, ammonia oxidation was a rate-limiting step. Furthermore, we focused on the relationship between NH4-N loading per AOB cell and nitrogen removal. Real time PCR monitoring results demonstrated that it is important to regulate NH4-N loading per AOB cell below 210 pg cell(-1) day(-1) to meet the effluent standard of advanced Johkasou. It is considered that NH4-N loading per AOB cell is a useful parameter for determining suitable nitrogen loading and small decentralized system design.


Asunto(s)
Amoníaco/metabolismo , Nitrógeno/aislamiento & purificación , Nitrosomonas/genética , Nitrosomonas/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Purificación del Agua , Aerobiosis , Biodegradación Ambiental , Recuento de Colonia Microbiana , Genes Bacterianos , Japón , Oxidación-Reducción , Temperatura
5.
Int J Oncol ; 8(4): 657-62, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21544409

RESUMEN

Using a fusion protein encoded by variant exon (v) 8-10 of CD44, a monoclonal antibody (mAb) 44-1V reactive with v9 product was generated. Western immunoblots and reverse transcriptase-polymerase chain reaction/Southern blot revealed that a 130 kilodalton component containing v8-10 products was specifically expressed in colorectal and gastric cancer cell lines. Immunohistological examination of 179 pairs of colorectal cancer and normal tissues revealed that about 47% of cancers expressed the CD44 variant (CD44v8-10), and its expression correlated with hematogenous and lymph node metastasis. These findings suggest the usefulness of CD44v8-10 in the prediction of colorectal cancer metastasis.

6.
Talanta ; 24(7): 467-9, 1977 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18962123

RESUMEN

A tensammetric method is proposed for the determination of microgram amounts of vanadium, based on catalysis of the oxidation of o-aminophenol with sodium chlorate in acidic solution (pH 2.0). The oxidation product gives a very sensitive tensammetric wave; under optimum conditions, the wave-height is proportional to the concentration of va vanadium. From 0.2 to 3.0 mug of vanadium can be determined in a final volume of 50 ml. Mo(VI), W(VI), Mn(VII), Ce(IV) and large amounts of Al(III) and Fe(III) cause positive errors, and Hg(II) and thiosulphate negative errors. Interference from Fe(III), Al(III) and Cu(II) can be eliminated by solvent with oxine at about pH 8.0.

7.
Talanta ; 22(7): 563-6, 1975 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18961687

RESUMEN

The rate of the ligand substitution reaction of copper (II)-PAN (CuR) with EDTA (Y) has been determined spectrophotometrically in 5% v/v dioxan over the pH range 5.0-6.3 at mu = 0.1 (NaClO(4)) and at 25 degrees . In the absence of 1,10-phenanthroline the rate law is expressed as -d[CuR(+)]/dt = 10(3.2) [CuR(+) [Y'], and the release of PAN from the reaction intermediate CuRY is the rate-determining step. In the presence of 1,10-phenanthroline (X), however, copper forms a stable mixed-ligand complex (CuRX(+)), and the rate of substitution with EDTA is expressed as -d[CuRX(+)]/dt = (10(6.2)[H(+)] + 10(4.8)[X]) [CuRX(+). The release of PAN from the mixed-ligand complex by H(+) and X is possibly the rate-determining step, with the copper-phenanthroline complexes produced undergoing fast exchange with EDTA. The stability constant of CuRX(+) has been determined spectrophotometrically in 5% v/v dioxan at mu = 0.1, and at 25 degrees as [CuRX(+)]/[Cu(2+)] [R(-)] [X] = 10(21.2). The acceleration of the rate of substitution of copper (II)-PAN chelate may be explained by the fact that the Cu-PAN bond in the distorted octahedral mixed-ligand complex CuRX is weaker than in the reaction intermediate CuRY.

8.
Talanta ; 19(4): 559-65, 1972 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18961084

RESUMEN

The use of ligand buffers composed of a chelating agent and an excess of polarographically inert metal is recommended for the selective polarographic determination of a metal in the presence of a second metal, which has a polarographic wave at a less negative potential than the metal to be determined. Theoretical considerations on the optimum ligand concentration and the optimum composition of the ligand buffer are followed by the determination of zinc in cadmium as an example.

9.
Talanta ; 20(9): 829-33, 1973 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18961352

RESUMEN

The rates of colour change reactions of metallochromic indicators such as XO, PAN, PAC and TAC at the equivalence point were measured in the chelatometric titration of copper, nickel, zinc or cobalt. Hexamine buffer has strong disturbing effects on the rate of colour change of the copper or nickel XO chelate. The effects of various auxiliary complex-forming agents were also examined. Bathophenanthroline, 2,2'-bipyridyl, 8-hydroxyquinoline, TPTZ, ethylenediamine, iminodiacetic acid, acetylacetone, 1,10-phenanthroline and glycine improve the colour change of the XO and PAN chelates of copper. Some titration methods for copper or nickel with XO or PAN as indicator are proposed.

10.
Talanta ; 23(2): 155-7, 1976 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18961825

RESUMEN

The rate of the ligand-substitution reaction of nickel(II)-TAC chelate (NiR(2)) with EDTA (Y) and 1,10-phenanthroline (X) has been determined spectrophotometrically in 20% v v dioxan over the pH range 5.7-6.3 at mu = 0.1 (KNO(3)) and 25 +/- 1 degrees . The substitution reaction with EDTA proceeds through the following two pathways: NiR(2) + H(+) right harpoon over left harpoon NiR(+) + HR, and NiR(2) + H(2)O right harpoon over left harpoon NiR(OH) + HR, The reaction of NiR(+) or NiR(OH) with EDTA is the rate-determining step, and k(1) = 2.1 x 10(3) l .mole(-1) .sec(-1) and k(2) = 7.9 x 10(6) l .mole(-1) .sec(-1).The substitution reaction with 1,10-phenanthroline proceeds as follows: NiR(+) + X right harpoon over left harpoon NiRX(+) At higher concentrations of 1,10-phenanthroline the release of TAC from NiR(2) by hydrogen ion is the rate-determining step, and k(3) = 2.4 x 10(5) l .mole(-1). sec(-1). At lower concentrations of 1,10-phenanthroline -d[NiR(2)]/dt is proportional both to [H(+)] and [X]. The value k(4) = 5.1 x 10(4) l. mole(-1). sec(-1) was calculated by the use of the steady-state approximation for [NiRX(+)]. The substitution with 1,10-phenanthroline proceeds much faster than that with EDTA. By the addition of a small amount of 1,10-phenanthroline, Ni can be titrated with EDTA at 50 degrees, with TAC as an indicator.

11.
Talanta ; 23(9): 669-71, 1976 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18961952

RESUMEN

The rate of ligand substitution of copper(II)-Xylenol Orange (XO) with EDTA (Y) has been determined spectrophotometrically over the pH range 4.8-6.0 at mu = 0.1 (KNO(3)) and at 25 degrees . In 2-(N-morpholino)ethane sulphonic acid buffer, copper forms a 2:1 chelate (Cu(2)XO(2-)) with XO, and the rate-law is expressed as -d[Cu(2)XO(2-)]/dt = 10(2.89)[Cu(2)XO(2)-][Y']- The release of the first copper ion from Cu(2)XO(2-) is the rate-determining step. The resulting CuHXO(3-) or CuH(2)XO(2-) may undergo fast substitution with EDTA. In the presence of hexamine, the copper(II)-XO chelate forms a mixed-ligand complex with hexamine (L). The formation constant K(Cu(2)XOL)(L) = [Cu(2)XOL(2-)]/[Cu(2)XO(2-)] [L] = 10(2.14) (mu = 0.1, 25 degrees ). At 3 x 10(-2)-2 x 10(-1)M hexamine the rate-law is expressed as -d[Cu(2)XOL(2-)]/dt = 5.39[Cu(2)XOL(2-)][Y']/[L']. The dissociation of hexamine from Cu(23)XOL(2-) has to precede the substitution reaction of Cu(2)XO(2-) with EDTA. Hence, hexamine at higher concentrations than 10(-3)M slows down the rate of colour change of XO in the copper-EDTA titration.

12.
Talanta ; 13(8): 1135-43, 1966 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18959983

RESUMEN

A method of indirect photometric determination of a very small amount of calcium is described. Optimum experimental conditions are deduced from theoretical considerations of the exchange equilibrium: M + NY + nA right harpoon over left harpoon MY + NA(n) Microgram quantities of calcium are successfully determined in the presence of magnesium and phosphates by means of either aqueous photometry or solvent extraction of NA(n).

13.
Talanta ; 21(1): 97-102, 1974 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18961425

RESUMEN

The acid dissociation constants of 1-(2-thiazolylazo)-2-hydroxy-3-naphthoic acid (TAHN) and the formation constants of Cu(II), Ni(II) and Zn(II) chelates of this dye have been determined spectrophotometrically at 25 degrees in a 5% v/v mixture of dioxan and water. The formation constants of the 1:2 chelates are smaller than those of other o-hydroxythiazolylazo compound chelates. TAHN is a satisfactory indicator for the titrations of Cu(II) and Ni(II) with EDTA.

14.
Talanta ; 24(1): 43-5, 1977 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18962019

RESUMEN

Semimicro to macro amounts of fluoride ion (0.4-100 mg) are determined rapidly and accurately by precipitation with an excess of lanthanum at pH 2.5-2.8 by digestion on a water-bath, cooling to room temperature, addition of excess of EDTA and back-titration of the excess with zinc solution to the Xylenol Orange end-point at ph 5.8-5..9. Large amounts of chloride, acetate and perchlorate, and small amounts of sulphate and silicate do not interfere, but phosphate does. This method is much superior to the usual thorium nitrate titration method and can be applied after preliminary separation of fluorine by steam distillation or pyrolysis.

15.
Talanta ; 42(6): 789-95, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18966293

RESUMEN

The partition of benzoic acid between 0.1M perchloric acid solution and two kinds of mixed solvents has been carried out at 25 degrees C. The partition and dimerization constants of benzoic acid have been determined in the 1-octanol-benzene and 2-octanone-benzene systems. In both the mixed solvent systems, with increasing content of 1-octanol and 2-octanone in each mixed solvent, the partition constant of benzoic acid has been found to increase, and the dimerization constant of benzoic acid in each organic phase to decrease. These phenomena are attributable to solvation of monomeric benzoic acid by 1-octanol and 2-octanone molecules in each mixed solvent.

16.
J Appl Biochem ; 5(4-5): 330-6, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6679544

RESUMEN

A new separation method using high-voltage capillary electrophoresis was applied to the analysis of several nucleotides. This system consisted of a micro-bore glass capillary column of 80-micron i.d., a high-voltage power supply, and a uv detector set at 254 nm. Seven nucleotides (cyclic AMP, AMP, ADP, ATP, GMP, GDP, and GTP) were separated completely from each other in 0.02 M phosphate buffer (pH 7) containing 0.5% ethylene glycol by applying about 150 V/cm. The theoretical plate number for AMP was nearly 45,000. A good separation of nucleotides in biological samples of rat blood, liver, and kidney was attained under the same conditions as above. Concentrations of nucleotides in these biological samples were measured by using pyridoxamine as an internal standard.


Asunto(s)
Riñón/análisis , Hígado/análisis , Ribonucleótidos/aislamiento & purificación , Animales , Electroforesis/métodos , Masculino , Ratas , Ribonucleótidos/sangre
17.
J Chromatogr ; 596(1): 73-8, 1992 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-1522180

RESUMEN

The reversed-phase high-performance liquid chromatography of 8-quinolinethiol (Hqt) complexes of Fe, Co, Ni, Cu, Zn, Hg and Pb on an octadecyl-bonded silica gel stationary phase was examined. The Pb complex dissociated in the column. The retention and separation of other complexes depended on the composition of the mobile phase. EDTA as an additive displaced the Zn complex and eliminated its peak. All the other metal complexes and also Hqt and its disulphide were separated in 23 min by using methanol-water (82:18, v/v) as the mobile phase. The complexes formed by the reaction of Co(II) and Hqt gave three peaks, which were assigned as fac(S)-CoIII(qt)3, mer(S)-CoIII(qt)3 and CoII(qt)2, respectively. This method is applicable to the simultaneous determination of Fe, Co, Ni, Cu and Hg.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Compuestos Organometálicos/aislamiento & purificación , Oxiquinolina/análogos & derivados , Cobalto/química , Cobre/química , Concentración de Iones de Hidrógeno , Hierro/química , Mercurio/química , Níquel/química , Compuestos Organometálicos/química , Espectrofotometría
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