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1.
Mar Pollut Bull ; 56(2): 170-86, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18082844

RESUMEN

The Sethu Samudram Canal Project (SSCP), considered as a harbinger of economic growth in India, is a mega engineering project being developed to provide a 260 km long, 300 m wide and 12 m deep shipping channel between the Arabian Sea and the Bay of Bengal. This project impacts the unique biota and biodiversity of a 10,500 km(2) Marine Biosphere Reserve. This man-made link facilitates exchange of water masses between the less saline Bay of Bengal and the more saline Arabian Sea. Initial construction, subsequent dredging for channel maintenance, and the associated ship traffic would result in irreversible changes to the already over-exploited and stressed environment. Additionally, the channel would form a deep ocean route for future tsunamis. However, to provide assurance to the public, particularly the 50,000 fishing folk, in 47 villages in this area, it would be crucial that a long-term environmental monitoring program is instituted. A thorough evaluation of the impending environmental impacts, similar to those addressed by a Before/After and Control/Impact (BACI model) is recommended.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Navíos , Animales , Economía , Peces/fisiología , Sedimentos Geológicos , India , Océanos y Mares , Petróleo , Navíos/economía , Movimientos del Agua , Contaminantes Químicos del Agua
2.
Bioresour Technol ; 98(2): 452-5, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16530408

RESUMEN

In this study, the adsorption properties of two different marine algae (Ulva fasciata (green algae) and Sargassum sp. (brown algae)) were investigated. Equilibrium isotherms and kinetics were studied to evaluate the relative ability of the two algae to sequester Cu(II) from aqueous solutions. The maximum biosorption capacity obtained was 73.5 mg g(-1) for U. fasciata and 72.5 mg g(-1) for Sargassum sp. at a solution pH of 5.5 +/- 0.5. A significant fraction of the total copper(II) uptake was achieved within 30 min. The copper(II) uptake by the biosorbents was best described by pseudo-second-order rate model.


Asunto(s)
Cobre/metabolismo , Sargassum/metabolismo , Ulva/metabolismo , Adsorción , Cinética
3.
FEBS Lett ; 158(2): 353-8, 1983 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-6409666

RESUMEN

We have reported that production and characterization of antibodies highly specific to 5-methyl-cytosine (5mC) and the development of a sensitive immunochemical method for the detection of 5mC in DNA [FEBS Lett. (1982) 150, 469]. Extension of this method to two other modified bases, 6-methyladenine (6mA) and 7-methylguanine (7mG), is reported here. By use of this immunochemical approach, we are able to detect 5mC, 6mA and 7mG in human and Drosophila DNA and confirm their presence in the DNA of two mealybug species.


Asunto(s)
Adenina/análogos & derivados , Citosina/análogos & derivados , ADN , Guanina/análogos & derivados , 5-Metilcitosina , Adenina/aislamiento & purificación , Animales , Anticuerpos , Fenómenos Químicos , Química , Citosina/aislamiento & purificación , Drosophila melanogaster , Femenino , Guanina/aislamiento & purificación , Humanos , Inmunoquímica , Insectos , Masculino , Placenta/metabolismo , Ratas , Especificidad de la Especie , Espermatozoides/metabolismo
4.
Artículo en Inglés | MEDLINE | ID: mdl-11887875

RESUMEN

A simple and sensitive method for the sequential determination of phosphate and arsenate was developed based on initial ion chromatographic separation followed by detection as the ion-association complex formed by heteropolymolybdophosphate and arsenate with bismuth. With 200 microl sample injection and separation on a AS4A-SC column using an eluent of 3.5 mM sodium hydrogen carbonate-10.0 mM sodium hydroxide, the detection limits which are calculated as the concentration equivalent to twice the baseline noise, were found to be 0.8 microg/l and 4.2 microg/l for P and As, respectively. Spiked samples were analyzed and recoveries were found to be satisfactory in the range of 95-105% for phosphate and 90-105% for arsenate. Samples of water and hair were analyzed by the proposed method.


Asunto(s)
Arseniatos/análisis , Cromatografía Liquida/métodos , Cabello/química , Fosfatos/análisis , Agua/química , Humanos , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría Ultravioleta
5.
Artículo en Inglés | MEDLINE | ID: mdl-15063348

RESUMEN

Thyroxine (3,5,3',5'-tetraiodo thyronine) is administered to patients suffering from endemic goiter as also in cases of non-iodine deficient ethiology and hypothyroidism. It is suggested that the uptake of thyroxine can be monitored by assessing the levels of the same in the urine of patients under treatment. For the purpose, a highly sensitive and selective ion chromatographic procedure is developed. The sample of urine is treated with sodium hydroxide and UV irradiated to convert iodine in thyroxine to iodide. Subsequently, iodide is separated on an anion exchanger AS 4A column using 50 mM NaOH as the eluent and determined spectrophotometrically at 226 nm.


Asunto(s)
Cromatografía por Intercambio Iónico/métodos , Tiroxina/orina , Humanos , Espectrofotometría Ultravioleta
6.
Am Surg ; 62(5): 356-60, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8615561

RESUMEN

From 1958 through 1992, 30 patients with hepatic hemangiomas were seen and treated at Children's Hospital Los Angeles. The majority of the patients were less 1 month of age (90 % younger than the first year of life) and there was no difference in sex distribution. Patients presented with coagulopathy, heart failure, abdominal mass, and respiratory distress. Eleven patients (33%) had hemangiomas in other sites. Fourteen patients were treated with steroid therapy. Of these, eight patients did not respond and received radiotherapy. Eleven patients who had the hemangioma confined to an anatomical lobe had resection of the hemangioma by liver lobectomy. Five of the most recent patients were successfully treated with hepatic artery embolization. Two other patients who were seen many years ago underwent diagnostic laparotomy and biopsy of the lesion before treatment with steroids. In one patient who presented with ruptured hepatic hemangioma, hepatic arterial ligation was performed. In another patient, seen recently, treatment with interferon alpha-2 was initiated, but the patient died. There were six deaths in the series. Four patients died of intractable congestive heart failure, steroids are given first. Course of steroid therapy may be repeated if necessary. Whereas formerly radiation therapy was added to the treatment of a patient resistant to steroids, therapeutic hepatic arterial embolization is a very good alternative for these patients. Surgical excision of the lesion can be performed by liver lobectomy if there is a solitary hemangioma within the boundaries of the surgical excision. Recently, in massive hemangioma with intractable thrombocytopenia, interferon alpha-2 therapy has been used, but so far our experience of this mode of therapy is limited.


Asunto(s)
Hemangioma/terapia , Neoplasias Hepáticas/terapia , Corticoesteroides/uso terapéutico , Algoritmos , Femenino , Hemangioma/complicaciones , Hemangioma/cirugía , Humanos , Lactante , Recién Nacido , Interferón-alfa/uso terapéutico , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/cirugía , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
7.
Talanta ; 30(6): 423-6, 1983 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18963388

RESUMEN

Molybdenum alpha-benzoin oximate is precipitated from homogeneous solution by hydrolysis of ethyl monochloroacetate to decrease the pH of an originally alkaline solution containing molybdenum and the oxime. The method can be used for assay of molybdenum compounds and ferromolybdenum.

8.
Talanta ; 36(3): 401-2, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18964725

RESUMEN

The determination of zirconium in the range 0.01-0.20% is required for some special alloy steels. A method has been developed, based on initial removal of iron as its chloro-complex by extraction with methyl isobutyl ketone, followed by further extraction after addition of potassium thiocyanate, and determination of the zirconium left in the aqueous phase, with Arsenazo III. The absorbance is measured at 665 nm.

9.
Talanta ; 24(6): 396-8, 1977 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18962110

RESUMEN

Dalzin forms coloured complexes with many metal ions. The present work deals with its use for determining microgram quantities of bismuth by solvent extraction followed by spectrophotometry. A method for estimation of bismuth in lead and nickel is presented.

10.
Talanta ; 27(6): 537-40, 1980 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18962721

RESUMEN

The determination of niobium at levels of 0.01% and below is required in certain specifications for stainless-steel welding electrodes, containing 2-3% molybdenum and 0.01% titanium. A method has been developed, based on initial extraction of niobium thiocyanate into butyl acetate followed by stripping with fluoride and re-extraction of niobium thiocyanate after masking of the fluoride by addition of boric acid. The absorbance of the extract is measured at 385 nm. Mo, Ti, V and W can be tolerated at 50 times the concentration of Nb. For higher amounts of Mo, corrections can also be applied. Ta should, however, be restricted to ten times the Nb level. Precision and accuracy of the method are satisfactory. The time taken for an individual determination is about an hour. The method is applicable to mild, low-alloy, stainless and niobium-stabilized steels.

11.
Talanta ; 49(3): 523-30, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18967627

RESUMEN

A rapid and sensitive sorbent extraction hydride generation-flow injection analysis atomic absorption spectrometric (HG-FIAS-AAS) method is described for the determination of As(III) and As(V) based upon online preconcentration on a microcolumn packed with activated alumina. In the present procedure these arsenicals are complexed with quinolin-8-ol-5-sulphonic acid from neutral solutions in the flow injection system and adsorbed on the column. The preconcentrated species are eluted with 10% HCl, mixed with 0.5% sodium borohydride and carried to the HG-FIAS cell with a carrier gas flow rate of 75 ml min(-1). The retention efficiency is found to be better than 98% with sensitivity enhancement of 12 and 10 for As(III) and As(V), respectively, for a 20 s preconcentration period. The respective detection limits are 0.05 and 2 ng ml(-1) for As(III) and As(V). The throughput of the samples is found to be 60 h(-1), with a loading time of 20 s. The method has been applied to sea water samples.

12.
Talanta ; 40(6): 771-4, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18965704

RESUMEN

A highly selective and sensitive spectrophotometric procedure for the determination of cadmium is developed. This is based on the interaction of rhodamine 6G with tetraiodocadmate (II) anion to form a pink product which absorbs maximally at 575 nm that is stable for 24 hr when stabilized with gelatin. Cadmium concentrations as low as 0.01 ppm can be readily determined. The method is precise and has been applied to synthetic sea water samples and high purity zinc materials.

13.
Talanta ; 42(1): 41-3, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18966197

RESUMEN

A sensitive spectrophotometric method has been developed for the determination of ziram in water, vegetables and grains. The method is based on the dissociation of dithiocarbamate complex of zinc with thiocyanate and rhodamine 6G at pH 4 to form a pink coloured complex that is stabilized by gelatin. The method is simple and Beer's law is obeyed over the concentration range of 0.05-1 ppm of ziram. The method is free from interference of similar dithiocarbamate fungicides containing Mn(2+) and Fe(3+) ions.

14.
Talanta ; 44(3): 423-6, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18966759

RESUMEN

A luminescence spectrometric method was developed for the determination of ultra trace amounts of europium (down to 1 x 10(-13) M) in high purity lanthanum, praseodymium and dysprosium oxides. This is based on the enhanced luminescence of europium-thenoyltrifluoroacetone (TTA)-dibenzo-18-crown-6 (DBC)-Triton X-100 in the presence of terbium. The fluorescence intensity is linear with europium concentration in the range 1 x 10(-11) - 1 x 10(-6) M under the recommended conditions. The optimized procedure is successfully utilized for the determination of ultratrace amounts of europium in lanthanium, praseodymium and dysprosium oxides.

15.
Talanta ; 43(1): 73-6, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18966465

RESUMEN

A d.c. polarographic technique has been used previously for the determination of the pesticide, ziram, in aqueous samples, this paper reports differential pulse anodic stripping voltammetric determination of ziram zinc in rice samples using a static mercury drop electrode. The procedure developed distinguishes inorganic zinc and ziram zinc in sodium acetate-sodium chloride media. The procedure developed is suitable for the determination of concentrations as low as 10 ppb of ziram with a precision of 2.1% for five successive determinations of 150 ppb of ziram.

16.
Talanta ; 44(1): 97-103, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18966721

RESUMEN

Mixed-ligand chelate extraction of trivalent lanthanides such as Nd(III), Eu(III) and Lu(III) into benzene with mixtures of 4,4,4-trifluoro-1-phenyl-1,3-butanedione (HBFA) and bis-2-ethylhexyl sulphoxide (B2EHSO) or triphenylphosphine oxide (TPhPO) from thiocyanate solutions was investigated. The results demonstrate that these metal ions are extracted as Ln(BFA)(3) with HBFA alone and in the presence of a neutral oxo-donor, B2EHSO or TPhPO(S), as Ln(BFA)(3).S and Ln(BFA)(3).2S. The equilibrium constants of the above species increase monotonically with decreasing ionic radii of these metals ions. The addition of a neutral donor to the metal chelate system not only enhances the extraction efficiency but also improves the selectivity among these trivalent lanthanides. Hence this mixed-ligand system may be useful for the extraction and separation of individual lanthanides and also for the separation of lanthanides as a group from other metal ions.

17.
J Pediatr Surg ; 30(9): 1267-70, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8523222

RESUMEN

Duplications of the alimentary tract are rare congenital anomalies that could present a diagnostic as well as therapeutic challenge. Twenty-seven patients with duplications of the alimentary tract were treated at Childrens Hospital Los Angeles between 1961 and 1992. Ages ranged from a few days to 5 years (67% younger than 1 year). The most common symptoms were nausea and vomiting, and the most common sign was a palpable abdominal mass. Three patients presented with gastric duplication, which was excised. The majority of the duplications were in the jejunum and ileum. All patients except one had primary resection of the duplication. One patient with a 45-cm tubular jejunal duplication was treated with mucosal stripping of the duplication. Five patients had cecal duplication, three patients presented with melena because of ectopic gastric tissue in the duplication, and two presented with intestinal obstruction. One of the latter patients presented with intussusception with cecal duplication as the leading point. Three patients with colonic duplication presented with abdominal pain and vomiting leading to excision of the duplication. Of the five patients with rectal duplication, three presented with chronic constipation. The other two patients presented elsewhere with perianal swelling, which eventually was drained because of a mistaken diagnosis of perianal abscess. Subsequently, these two patients came to us with persistent perineal fistula. In all our patients, rectal duplications were removed through a sacroperineal incision. The only patient in this series who died was a 6-week-old boy with gastric duplication; his death was attributed to an associated severe cardiac lesion.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Anomalías del Sistema Digestivo , Anomalías Múltiples , Preescolar , Procedimientos Quirúrgicos del Sistema Digestivo , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Suelo de la Boca/anomalías , Complicaciones Posoperatorias
18.
J Pediatr Surg ; 30(10): 1502-3, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8786503

RESUMEN

The authors describe an unusual case of benign mesenchymoma of the groin in a 9-month-old boy.


Asunto(s)
Mesenquimoma/cirugía , Neoplasias de los Tejidos Blandos/cirugía , Ingle , Humanos , Lactante , Masculino
19.
J Perinatol ; 34(2): 105-11, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24355940

RESUMEN

OBJECTIVE: Little is known about the effect of obesity on inflammatory status in pregnant women. The objective of this study was to determine the effect of obesity on markers of inflammation, oxidative stress and micronutrient status in obese pregnant women and their infants compared with lean controls (Lc). STUDY DESIGN: This was a prospective case-control study. A total of 15 obese (Ob; body mass index (BMI) >30 kg m(-2)) and 15 lean (BMI 18-25 kg m(-2)) women were recruited based on prepregnancy BMI. Vitamins A, B6, C, E and 25-hydroxyvitamin D (25(OH)D), zinc, red blood cell (RBC) folate, C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-α and oxidized and reduced glutathione were measured from maternal blood between 24 and 28 weeks of gestation. Vitamins A, B6, C and E, 25(OH)D, zinc, red blood cell folate, CRP and IL-6 were measured from cord blood at delivery. RESULT: Ob pregnant women have statistically significantly lower levels of vitamin B6, vitamin C, vitamin E, RBC folate, higher CRP and IL-6 levels and higher ratio of oxidized to reduced glutathione compared with Lc pregnant women. Infants born to Ob mothers did not have statistically significantly higher measures of inflammation or oxidative stress. There were no differences in micronutrient concentrations between Lc and Ob infants, but folate, vitamin B6 and zinc levels correlated strongly between mother and infant. There was no statistically significant difference in any parameter between Ob and Lc cord blood. CONCLUSION: Ob pregnant women have increased inflammation and oxidative stress, and lower levels of nutritional antioxidant defenses compared with Lc pregnant women. We speculate that lower antioxidant defenses combined with increased oxidative stress and inflammation may contribute to the adverse outcomes associated with pregnancy in Ob women.


Asunto(s)
Antioxidantes/análisis , Sangre Fetal/química , Recién Nacido/sangre , Micronutrientes/sangre , Obesidad/sangre , Complicaciones del Embarazo/sangre , Embarazo/sangre , Vitaminas/sangre , Adulto , Índice de Masa Corporal , Estudios de Casos y Controles , Femenino , Humanos , Estudios Prospectivos
20.
J Perinatol ; 33(3): 177-81, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22722675

RESUMEN

OBJECTIVE: To ascertain the effect of obesity-related inflammation on maternal and fetal iron status. We hypothesized that obese (Ob) pregnant women would have increased inflammation, hepcidin levels, and that their infants would have impaired iron status compared with lean (Lc) controls. STUDY DESIGN: Fifteen Ob and fifteen Lc women were recruited in their second trimester of pregnancy. Markers of iron status, inflammation and hepcidin were measured in maternal and cord blood. Student's t-test was used to compare Ob and Lc groups, and Pearson's correlation coefficients were determined between maternal and cord blood values. RESULT: Maternal C-reactive protein (P<0.01) and hepcidin (P<0.01) were higher, and cord blood iron (P<0.01) was lower in the Ob group. Maternal body mass index (P<0.01) and hepcidin (P<0.05) were negatively correlated with cord blood iron status. CONCLUSION: Maternal obesity is associated with impaired maternal-fetal iron transfer, potentially through hepcidin upregulation.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/sangre , Sangre Fetal/química , Feto/fisiología , Intercambio Materno-Fetal/fisiología , Obesidad/sangre , Obesidad/fisiopatología , Complicaciones del Embarazo/sangre , Complicaciones del Embarazo/fisiopatología , Adulto , Índice de Masa Corporal , Proteína C-Reactiva/análisis , Estudios de Casos y Controles , Femenino , Hepcidinas , Humanos , Estrés Oxidativo/fisiología , Embarazo , Segundo Trimestre del Embarazo , Regulación hacia Arriba
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