RESUMEN
The evaporation of As-rich leachates generated by the weathering of sulfide-rich mine wastes accumulated in abandoned tailing dams of the La Concordia mine, triggers the widespread precipitation of saline crusts and efflorescences. Because these salts are highly soluble, they may release high concentrations of arsenic after rainfall events. Thus, the goal of this work is to assess the solid speciation of As in these efflorescences, which may help to understand the short-term cycling of As in the site. The results reveal that As is present only as As(V), while its capacity to be retained in the salts highly depends on their mineralogical composition. Hydrous sulfates, such as gypsum and epsomite show a very low capacity to scavenge As, while copiapite retains the highest concentrations of this element. The spectroscopic evidences suggest that in this mineral, As(V) is included within the lattice, substituting sulfate in the tetrahedral sites. Because copiapite is highly soluble, it may be considered as one of the most important transient reservoirs of As in the site that can release high concentrations of this hazardous pollutant during the occasional rainfall events produced during the wet season.
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The analysis of X-chromosome STRs is useful in certain kinship cases for which autosomal markers provide insufficient statistical power. Particularly, powerful results are achieved in paternity cases with a daughter, when the alleged father is not accessible for analysis, contrarily to his unquestioned mother or daughter. However, representative haplotype frequencies for this type of markers are not available for some populations, as is the case of Argentina, which prevents the quantification of the proof in routine forensic analyses. In this work we present haplotype frequencies for the 12 X-chromosome STRs included in the Investigator Argus X-12 kit, as well as segregation data, obtained from the analysis of the genetic profiles of 457 father-daughter duos, which gave us information on 914 (unrelated) haplotypes from residents of all Argentinian provinces.
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Cromosomas Humanos X , Genética de Población , Haplotipos , Repeticiones de Microsatélite , Argentina , Dermatoglifia del ADN , Femenino , Frecuencia de los Genes , Humanos , Desequilibrio de Ligamiento , MasculinoRESUMEN
This paper describes the weathering processes that occurred across two tailing dumps in the Concordia mine (Puna of Argentina) with the purpose of evaluating the formation of secondary As-bearing minerals due to arsenopyrite alteration. After 30â¯years of exposure, the gradual oxidation of the wastes produced a number of secondary mineral phases containing As in different chemical arrangements. Synchrotron-based X-ray absorption spectroscopy was used to determine both, As and Fe solid speciation and to identify the formed As-bearing minerals. The results reveal that in the first stages of oxidation, As released from arsenopyrite is adsorbed/substituted in the jarosite structure partially inhibiting its dissolution. When pH values in the system slightly increase As-jarosite transforms into schwertmannite, where the released As could be re-adsorbed or co-precipitated. When the available adsorption sites become oversaturated with As, the precipitation of amorphous ferric arsenates may occur. The latter, likely constitute the more labile As fractions in the sediments and are therefore the main phases contributing As to the nearby environments. These amorphous and labile phases are more abundant in the uppermost layers of the profiles, where oxidation has taken place for a more prolonged time-lapse. The described transformations are enhanced by the acidic pH, the absence of minerals attenuating the acidity and the high sulfate and As concentrations in pore water.
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The coastal plain of the middle estuary of the Río de la Plata is a highly industrialized area and is densely populated by sectors. The main human activity in the sector encompassed between the cities of Ensenada and Berisso is associated with the petrochemical industry. In this work, hydrogeochemical and isotopic characteristics of surface and groundwater in the impacted area are analyzed and the results are contrasted with those obtained in an undisturbed protected area. Major and trace elements were determined using standardized methods while the stable isotopes δ18O y δ2H were analyzed by mass spectroscopy. Human impact is evidenced by the occurrence of large variations in the major chemical composition of water, and also by the elevated concentrations of some trace elements that are not contributed from natural sources. These results may contribute to the understanding of chemical processes and pollutants distribution in highly industrialized coastal plain areas.
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Agua Subterránea , Isótopos/análisis , Argentina , Ciudades , Monitoreo del Ambiente , Humanos , Contaminantes Químicos del AguaRESUMEN
INTRODUCTION AND OBJECTIVE: Vitiligo is a chronic autoimmune skin disease caused by the destruction of melanocytes. Although quality of life (QOL) in vitiligo has been studied in different countries, it has not yet been investigated in Mexico. The aim of this study was to assess the QOL of Mexican patients with vitiligo. MATERIAL AND METHOD: We conducted a cross-sectional study at the research unit of Centro Dermatológico Dr. Ladislao de la Pascua in Mexico City. We included adults with vitiligo and excluded those with other pigmentation disorders or a neurological or psychiatric disorder. Patients on psychoactive medications were also excluded. All the patients were administered the Dermatology Life Quality Index (DLQI), a vitiligo-specific quality of life instrument (the VitiQoL), and the Beck Depression and Anxiety Inventories. RESULTS: We studied 150 patients with vitiligo (103 women [68.7%] and 47 men [31.3%]). The median (interquartile range) age was 38 (20) years. The mean (SD) scores on the DLQI and VitiQoL were 5.2 (5.4) and 32.1 (22.7) out of total possible scores of 30 and 90, respectively. The correlation between questionnaire scores was 0.675 (P<.001). Patients with genital involvement scored significantly worse on the VitiQoL than those without lesions in this area (43.95 [28.4]) vs. 28.98 [20.08], P<.001). The prevalence of depression and anxiety was 34% and 60%, respectively. CONCLUSION: Vitiligo has a minimal impact on the QOL of our patients. QOL was worse in patients with genital lesions.
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Calidad de Vida , Vitíligo/psicología , Adolescente , Adulto , Ansiedad/etiología , Estudios Transversales , Depresión/etiología , Femenino , Humanos , Masculino , México , Factores Socioeconómicos , Encuestas y Cuestionarios , Evaluación de Síntomas , Vitíligo/tratamiento farmacológico , Adulto JovenRESUMEN
Currently, nanomaterials had been used for several applications; one of them is as bio-markers. These nanomaterials contain fluorescent compounds as effective indicators for imaging and other applications in Biotechnology. In previous studies, we proposed a functionalized nanomaterial-based biomarker from silica and Eysenhardtia Polystachia, a medicinal tree known in Mexico as "palo azul" (Kidneywood). Our previous results showed the feasibility of the nanomaterial obtained as bio-marker. In this article, our purpose is to evaluate the effects of extraction solvents on fluorescence of that biomarker. The photoluminescence (PL) effect was evaluated at different pH (4, 7.4 and 8); four extraction solvents, ethanol, methanol, methanol-ethanol and methanol-ethanol-water were evaluated. A molecular dynamics simulation was performed to recognize molecular interaction between the compounds of the extracts with solvent molecules and to investigate the solvent molecules effect on photoluminescence spectra. The results were also compared with rhodamine 6G and we found that, at physiological pH (7.4), the fluorescent-coated silica nanoparticles obtained were also stable. We found that extraction solvents could be used for obtaining different nanomaterials for specific applications, and also found the best extraction solvent for obtaining EP nanomaterials for health care applications, specifically for imaging techniques.
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Biomarcadores/análisis , Fabaceae/química , Extractos Vegetales/química , Solventes/química , Etanol/química , Fabaceae/metabolismo , Concentración de Iones de Hidrógeno , Metanol/química , Nanopartículas/química , Teoría Cuántica , Rodaminas/química , Dióxido de Silicio/química , Espectrofotometría Ultravioleta , Espectrometría Raman , Electricidad Estática , Agua/químicaRESUMEN
The sulfide-rich residues of La Concordia mine, Argentina Puna, are accumulated in tailing dams that remained exposed to the weathering agents for almost 30years. In such period of time, a complex sequence of redox and dissolution/precipitation reactions occurred, leading to the gradual oxidation of the wastes and the formation of weathering profiles. The sources of arsenic in the wastes were analyzed by XRD and SEM/EDS analysis while a standardized sequential extraction procedure was followed to define solid As associations. In addition, the release of As during sediment-water interaction was analyzed in a period of 10months. The results indicate that primary As-bearing minerals are arsenian pyrite and polymetallic sulfides. As-jarosite and scarce arsenates are the only secondary As-bearing minerals identified by XRD and SEM/EDS. However, the rapid release (i.e., <1h) of arsenic from suspensions of the studied sediments in water, seems to be associated to the dissolution of highly soluble (hydrous)sulfates, as it was determined in samples of the efflorescences that cover the entire site. Contributions from the more abundant As-jarosite are also expected in longer periods of sediment-water interaction, due to its low rate of dissolution in acid and oxic conditions. Finally, near 30% of As remains adsorbed onto Fe (hydr)oxides thus representing a hazardous reservoir with the potential of mobilizing As into porewaters and streamwaters if the acidic and oxidizing conditions that predominate in the region are altered.
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INTRODUCTION: The development of the human haemochorial placenta requires complex regulatory mechanisms to protect invasive trophoblast cells from cytotoxic responses elicited by maternal immune cells. Leptin, the adipocyte derived hormone encoded by the Lep gene, is synthesized by placental trophoblasts and exerts pleiotropic effects on the immune system, including the promotion of inflammation and the activation of T cell responses. METHODS: To address its possible involvement in the modulation of maternal immune responses during pregnancy, we investigated the effect of leptin on the expression of the class Ib histocompatibility antigen HLA-G as one of the chief immunosuppressive strategies used by trophoblast cells. RESULTS: In vitro incubation of the trophoblast derived Swan 71 and JEG-3 cell lines with 25-50 ng/ml recombinant leptin significantly boosted HLA-G mRNA and protein expression, and this effect was abrogated upon pharmacological inhibition of the PI3K-Akt and MEK-Erk signaling pathways. A similar stimulatory effect of leptin was observed in term placental tissue explants, though 10-fold higher doses were required for stimulation. Further, JEG-3 cells treated with a leptin antisense oligodeoxynucleotide displayed decreased HLA-G expression levels, which were partially recovered by addition of stimulating doses of exogenous hormone. Immunofluorescence and qPCR analysis confirmed leptin biosynthesis in placental tissue, further showing that invasive extravillous trophoblast cells were a main source of this hormone during the first trimester of normal pregnancies. DISCUSSION: Taken together, our results show that leptin acts as an autocrine/paracrine signal promoting HLA-G expression in placental trophoblasts suggesting an important role in the regulation of immune evasion mechanisms at the fetal maternal interface.
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Regulación del Desarrollo de la Expresión Génica , Antígenos HLA-G/metabolismo , Leptina/metabolismo , Fosfatidilinositol 3-Quinasa/metabolismo , Placentación , Transducción de Señal , Trofoblastos/metabolismo , Adulto , Línea Celular , Femenino , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Silenciador del Gen , Antígenos HLA-G/química , Antígenos HLA-G/genética , Humanos , Leptina/antagonistas & inhibidores , Leptina/genética , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Oligodesoxirribonucleótidos Antisentido , Placentación/efectos de los fármacos , Embarazo , Primer Trimestre del Embarazo , Tercer Trimestre del Embarazo , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Transducción de Señal/efectos de los fármacos , Técnicas de Cultivo de Tejidos , Trofoblastos/citología , Trofoblastos/efectos de los fármacos , Trofoblastos/inmunologíaRESUMEN
Secreted protein, acidic and rich in cysteine (SPARC) is involved in many biological process including liver fibrogenesis, but its role in acute liver damage is unknown. To examine the role of SPARC in acute liver injury, we used SPARC knock-out (SPARC(-/-)) mice. Two models of acute liver damage were used: concanavalin A (Con A) and the agonistic anti-CD95 antibody Jo2. SPARC expression levels were analyzed in liver samples from patients with acute-on-chronic alcoholic hepatitis (AH). SPARC expression is increased on acute-on-chronic AH patients. Knockdown of SPARC decreased hepatic damage in the two models of liver injury. SPARC(-/-) mice showed a marked reduction in Con A-induced necroinflammation. Infiltration by CD4+ T cells, expression of tumor necrosis factor-α and interleukin-6 and apoptosis were attenuated in SPARC(-/-) mice. Sinusoidal endothelial cell monolayer was preserved and was less activated in Con A-treated SPARC(-/-) mice. SPARC knockdown reduced Con A-induced autophagy of cultured human microvascular endothelial cells (HMEC-1). Hepatic transcriptome analysis revealed several gene networks that may have a role in the attenuated liver damaged found in Con A-treated SPARC(-/-) mice. SPARC has a significant role in the development of Con A-induced severe liver injury. These results suggest that SPARC could represent a therapeutic target in acute liver injury.
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Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Células Endoteliales/fisiología , Osteonectina/genética , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/inmunología , Concanavalina A , Endotelio Vascular/patología , Técnicas de Silenciamiento del Gen , Lipopolisacáridos/farmacología , Hígado , Masculino , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Osteonectina/metabolismo , TranscriptomaRESUMEN
We analyze the sources and mechanisms that control the release of fluoride from sediments collected from two types of aquatic reservoirs in the central region of Argentina: 1) mountainous rivers draining crystalline rocks from the Sierras Pampeanas ranges, and 2) shallow aquifers in loessic sediments. The assessment was performed on the basis of experimental work and the study of chemical and mineralogical characteristics of sediments in contact with F-rich waters of the studied region. The chemical and mineralogical compositions of sediments were analyzed by ICP/OES, DRX, and SEM-EDS. Batch experiments were conducted to evaluate the kinetics of fluoride release under variable pH and ionic composition of the solution. The enhanced release of fluoride at more acidic pH, the inhibition of release in Ca-rich solutions and the positive significant linear trends between Ca(2+) and fluoride concentrations suggest that the dissolution of a Ca/F-bearing phase (like fluorapatite) strongly controls the dynamics of fluoride in the early stages of water-sediment interaction, particularly under acidic conditions. Calculations revealed that the dissolution of an amount of FAp equivalent to that estimated in the studied sediments may widely account for the values measured in the leaching experiments at pH6, whatever the dominant cation in the solution. Under such conditions, dissolution of FAp (present as coatings onto glass surfaces or as detritic grains) is likely the major primary source of fluorine in the studied sediments. Contribution from biotite may be also considered as a source in fluvial sediments. When adequate surfaces are present the released anions may partially be scavenged from the solution by adsorption at acidic pH. Increasing alkalinity in the aquatic reservoirs may then release the adsorbed fluoride through desorption or through competition with other anionic species. Comparing both mechanisms, dissolution predominates at lower pH while desorption is the main contribution under alkaline conditions.
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Fluoruros/química , Argentina , Concentración de Iones de Hidrógeno , Cinética , Microscopía Electrónica de Rastreo , Espectrometría por Rayos XRESUMEN
Mesenchymal stem (stromal) cells (MSCs) are a source of circulating progenitors that are able to generate cells of all mesenchymal lineages and to cover cellular demands of injured tissues. The extent of their transdifferentiation plasticity remains controversial. Cells with MSC properties have been obtained from diverse tissues after purification and expansion in vitro. These cellular populations are heterogeneous and under certain conditions show pluripotent-like properties. MSCs present immunosuppressive and anti-inflammatory features and high migratory capacity toward inflamed or remodeling tissues. In this study we review available data regarding factors and signaling axes involved in the chemoattraction and engraftment of MSCs to an injured tissue or to a tissue undergoing active remodeling. Moreover, experimental evidence in support of uses of MSCs as vehicles of therapeutic genes is discussed. Because of its regenerative capacity and its particular immune properties, the liver is a good model to analyze the potential of MSC-based therapies. Finally, the potential application of MSCs and genetically modified MSCs in liver fibrosis and hepatocellular carcinoma (HCC) is proposed in view of available evidence.
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Carcinoma Hepatocelular/terapia , Terapia Genética , Cirrosis Hepática/terapia , Neoplasias Hepáticas/terapia , Células Madre Mesenquimatosas , Animales , Quimiotaxis , Técnicas de Transferencia de Gen , Ingeniería Genética , Células Madre Mesenquimatosas/inmunología , Células Madre Mesenquimatosas/fisiología , RatonesRESUMEN
The effects of water stress on leaf water relations and growth are reported for three perennial tussock grass genotypes under glasshouse conditions. Studies were performed in genotypes El Palmar INTA and Selección Anguil of Agropyron scabrifolium (D÷ell) Parodi, and El Vizcachero of A. elongatum (Host) Beauv. Agropyron scabrifolium El Palmar INTA is native to a region with warm-temperate and humid climate without a dry season, and an average annual precipitation of 900 mm. Agropyron scabrifolium Selección Anguil comes from a region with a sub-humid, dry to semiarid climate and a mean annual precipitation of 600 mm. Agropyron elongatum is a widespread forage in semiarid Argentina with well-known water stress resistance. A mild water stress treatment was imposed slowly; plants reached a minimum pre-dawn leaf water potential of about -1.83 MPa by day 21 after watering was withheld. In all genotypes, water stress led to a reduction of leaf growth. There was a tendency for a greater epicuticular wax accumulation on water-stressed plants of A. scabrifolium Selección Anguil and A. elongatum than on those of A. scabrifolium El Palmar INTA. This may have contributed to obtain greater turgor pressures and relative water contents in the first two than in the later genotype. In turn, this may have contributed to determine smaller leaf growth rate reductions in A. scabrifolium Selección Anguil and A. elongatum than in A. scabrifolium El Palmar INTA under water stress. This study demonstrated variation in water stress resistance between genotypes in A. scabrifolium, and between A. scabrifolium Selección Anguil and A. elongatum versus A. scabrifolium El Palmar INTA, which was related to their differential responses in water relations. (AU)
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Agropyron/genética , Agropyron/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Agua/metabolismo , Agricultura , Agropyron/efectos de los fármacos , Desastres Naturales , Presión Osmótica , Hojas de la Planta/efectos de los fármacos , Factores de Tiempo , Agua/farmacología , Ceras/análisisRESUMEN
The effects of water stress on leaf water relations and growth are reported for three perennial tussock grass genotypes under glasshouse conditions. Studies were performed in genotypes El Palmar INTA and Selección Anguil of Agropyron scabrifolium (Dõell) Parodi, and El Vizcachero of A. elongatum (Host) Beauv. Agropyron scabrifolium El Palmar INTA is native to a region with warm-temperate and humid climate without a dry season, and an average annual precipitation of 900 mm. Agropyron scabrifolium Selección Anguil comes from a region with a sub-humid, dry to semiarid climate and a mean annual precipitation of 600 mm. Agropyron elongatum is a widespread forage in semiarid Argentina with well-known water stress resistance. A mild water stress treatment was imposed slowly; plants reached a minimum pre-dawn leaf water potential of about -1.83 MPa by day 21 after watering was withheld. In all genotypes, water stress led to a reduction of leaf growth. There was a tendency for a greater epicuticular wax accumulation on water-stressed plants of A. scabrifolium Selección Anguil and A. elongatum than on those of A. scabrifolium El Palmar INTA. This may have contributed to obtain greater turgor pressures and relative water contents in the first two than in the later genotype. In turn, this may have contributed to determine smaller leaf growth rate reductions in A. scabrifolium Selección Anguil and A. elongatum than in A. scabrifolium El Palmar INTA under water stress. This study demonstrated variation in water stress resistance between genotypes in A. scabrifolium, and between A. scabrifolium Selección Anguil and A. elongatum versus A. scabrifolium El Palmar INTA, which was related to their differential responses in water relations.
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Agropyron/genética , Agropyron/metabolismo , Agua/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Agricultura , Agropyron/efectos de los fármacos , Agua/farmacología , Ceras/análisis , Hojas de la Planta/efectos de los fármacos , Desastres Naturales , Presión Osmótica , Factores de TiempoRESUMEN
Cancer cells may frequently develop cross-resistance to structurally dissimilar chemotherapeutic agents. However, the molecular mechanisms for sensitivity and resistance of tumor cells towards chemotherapy are still partially understood. Antineoplasic drugs have been shown to induce apoptosis in chemosensitive leukemias and solid tumors. In this work, cross-resistance among vincristine (VCR), doxorubicin (DOX) and other antineoplasic agents commonly used in the treatment of leukemia such as etoposide (VP-16), methotrexate (MTX), cyclophosphamide (CTX), dexamethasone (DEX), cytarabine (Ara-C) and L-asparaginase on vincristine resistant (LBR-V160), doxorubicin resistant (LBR-D160) and sensitive (LBR-) murine leukemic T cell lines, was determined. The effect of antineoplasic agents was assayed by tritiated thymidine incorporation. Our results showed that VCR exhibited cross-resistance with DOX, VP-16, DEX and MTX, while DOX demonstrated cross-resistance with VCR, VP-16 and MTX. Ara-C failed to present cross-resistance with any cell line. Apoptosis induced by the above drugs on the same cell lines was analyzed by acridine orange and ethidium bromide staining, DNA hypoploidy (flow cytometry) and oligonucleosomal fragmentation of nuclear DNA showing that therapeutic concentrations of these chemotherapeutic agents induced apoptosis in the LBR- cell line. Our results demonstrated that, except for DEX, none of the drugs presenting cross-resistance were able to induce cell death on LBR-V 160 or LBR-D 160 cell lines.
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Apoptosis/efectos de los fármacos , Resistencia a Múltiples Medicamentos , Leucemia de Células T/patología , Células Tumorales Cultivadas/efectos de los fármacos , Animales , Antineoplásicos/farmacología , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacología , Etopósido/farmacología , Metotrexato/farmacología , Ratones , Vincristina/farmacologíaRESUMEN
STUDY DESIGN: We conducted a historic cohort study of neonates who received platelet transfusions at the National Institute of Perinatology, Mexico City, from January 1997 to May 2000. We obtained descriptive and outcome data, and assessed demographic and laboratory means of predicting "good candidates" for a future recombinant thrombopoietin (rTpo) trial. RESULTS: A minority of the transfused patients (11.4%) received only one transfusion; the majority (88.6%) received multiple transfusions. Neonates who received one or more platelet transfusions were more likely to die (24.5% mortality) than neonates who received no platelet transfusions (3.7% mortality). Regression analyses indicated that the presence of liver disease was the best predictor of a "good candidate" for rTpo administration. CONCLUSION: The majority of neonates in our institution who receive platelet transfusions receive multiple, not single, transfusions. Receiving any platelet transfusion is a marker for high risk of death. Neonates with liver disease who receive platelet transfusions might be a reasonable group for a phase I rTpo trial.
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Unidades de Cuidado Intensivo Neonatal/estadística & datos numéricos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Transfusión de Plaquetas/estadística & datos numéricos , Trombocitopenia/epidemiología , Trombocitopenia/terapia , Estudios de Cohortes , Femenino , Humanos , Mortalidad Infantil , Recién Nacido , Masculino , México/epidemiología , Selección de Paciente , Valor Predictivo de las Pruebas , Trombopoyetina/administración & dosificación , Trombopoyetina/uso terapéuticoRESUMEN
Blood cell lymphocyte chromosomes from untreated (UT) and clinically-cured (CC) patients with paracoccidioidomycosis and from healthy (control) people (CO) were studied. The frequency of aneuploid cells in the UT patients was higher than in the CC and CO individuals. The frequency of metaphase cells with premature centromere division was significantly higher in the UT than in the CC and CO group. No structural aberration and no statistically significant difference in the frequency of polyploidy was observed in the three groups studied. Our findings are indicative of an aneugenic (aneuploidy-inducing) action of infection by Paracoccidioides brasiliensis.
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Aberraciones Cromosómicas/genética , Linfocitos/ultraestructura , Paracoccidioidomicosis/genética , Adulto , Femenino , Humanos , Masculino , Metafase , Persona de Mediana Edad , Paracoccidioidomicosis/sangre , PloidiasRESUMEN
A method for the extraction and separation of the active ingredient diazepam (7-chloro-di-hydro-1-methyl-5-phenyl-2H, -1,4-benzodiazepam-2-one) in pharmaceutical tablets is discussed. This method avoids the hydrolysis of diazepam. Polarographic studies with direct current (DCP), alternating current (ACP) and differential pulse polarography (DPP) were used under different sets of conditions. The pH value most suitable for these studies was found to be 4.6. The detection range for ACP was found to be from 17.4 to 167 muM, whereas for DPP, the range was 4.8-96 muM. Commercial tablets of diazepam labelled to contain 10 mg per tablet were assayed. For five replicate samples, the relative standard deviations were lower than 1% and the contents were determined with errors lower than 4%.