Evaluation of processes controlling the geochemical constituents in deep groundwater in Bangladesh: spatial variability on arsenic and boron enrichment.

Forty-six deep groundwater samples from highly arsenic affected areas in Bangladesh were analyzed in order to evaluate the processes controlling geochemical constituents in the deep aquifer system. Spatial trends of solutes, geochemical modeling and principal component analysis indicate that carbonate dissolution, silicate weathering and ion exchange control the major-ion chemistry. The groundwater is dominantly of Na-Cl type brackish water. Approximately 17% of the examined groundwaters exhibit As concentrations higher than the maximum acceptable limit of 10 microg/L for drinking water. Strong correlation (R(2)=0.67) of Fe with dissolved organic carbon (DOC) and positive saturation index of siderite suggests that the reductive dissolution of Fe-oxyhydroxide in presence of organic matter is considered to be the dominant process to release high content of Fe (median 0.31 mg/L) in the deep aquifer. In contrast, As is not correlated with Fe and DOC. Boron concentration in the 26% samples exceeds the standard limit of 500 microg/L, for water intended for human consumption. Negative relationships of B/Cl ratio with Cl and boron with Na/Ca ratio demonstrate the boron in deep groundwater is accompanied by brackish water and cation exchange within the clayey sediments.

Acceleration of palatal wound healing in Smad3-deficient mice.

Wound healing is a well-orchestrated complex process leading to the repair of injured tissues. It is suggested that transforming growth factor (TGF)-beta/Smad3 signaling is involved in wound healing. The purpose of this study was to investigate the role of TGF-beta/Smad3 signaling in palatal wound healing in Smad3-deficient (Smad3(-/-)) mice. Histological examination showed that wound closure was accelerated by the proliferation of epithelium and dermal cells in Smad3(-/-) mice compared with wild-type (WT) mice. Macrophage/monocyte infiltration at wounded regions in Smad3(-/-) mice was decreased in parallel with the diminished production of TGF-beta1, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1alpha compared with WT mice. Fibrocytes, expressing hematopoietic surface marker and fibroblast products, were recruited and produced alpha-smooth-muscle actin in WT mice, but were not observed in Smad3(-/-) mice. These results suggest that TGF-beta/Smad3 signaling may play an important role in the regulation of palatal wound healing.

Hydrogeochemistry and arsenic contamination of groundwater in the Ganges Delta Plain, Bangladesh.

Geochemical composition and the level of Arsenic (As) contamination of groundwater in the Ganges Delta Plain, southwestern Bangladesh were elucidated. Hydrogeochemical data of tube well samples suggested that the groundwater is mostly Ca-Mg-HCO(3) type with bicarbonate (HCO(3)(-)) as the dominant anion, though other type waters are also observed. In contrast, the elevated EC, Cl(-) and high content of Na(+) relative to Ca(2+), Mg(2+) and K(+) in six groundwater samples suggest their saline origin. Low concentrations of NO(3)(-) and SO(4)(2-), and high concentrations of dissolved organic carbon (DOC), HCO(3)(-) and PO(4)(3-) indicate the reducing conditions of subsurface aquifer where sediments are deposited with abundant organic matter. The total As concentration in the analyzed samples is very high (0.0431-1.352 mg/L) along with high Fe (2.791-17.058 mg/L) and relatively low Mn (0.134-1.972 mg/L) at different depths. Distinct relationship of As with Fe and Mn, and strong correlation with DOC suggests that the biodegradation of organic matter and reductive dissolution of Fe-oxyhydroxide is considered to be the dominant processes to release As in aquifers. Moreover, negative correlation between As and SO(4)(2-) demonstrates the As may not be directly mobilized from sulfide minerals like arsenopyrite.

Interaction of native alpha-cyclodextrin, beta-cyclodextrin and gamma-cyclodextrin and their hydroxypropyl derivatives with selected organic low molecular mass compounds at elevated and subambient temperature under RP-HPLC conditions.

The main focus of this study was to explore the capability of native alpha-cyclodextrin, beta-cyclodextrin and gamma-cyclodextrin and their hydroxypropyl derivatives for host-guest interaction with 7,8-dimethoxyflavone, selected steroids (estetrol, estriol, estradiol, estrone, testosterone, cortisone, hydrocortisone, progesterone and 17alpha-hydroxyprogesterone) and polycyclic aromatic hydrocarbons (toluene, naphthalene, 1,8-dimethylnaphthalene, 1-acenaphthenol, acenaphthylene and acenaphthene) under reversed-phase liquid-chromatography conditions. The study revealed that native cyclodextrins interact more efficiently with the analytes investigated than do their hydroxypropyl counterparts. In the low-temperature region, enormously high ratios were observed for polycyclic aromatic hydrocarbons, particularly 1,8-dimethylnaphthalene, acenaphthene and acenaphthylene chromatographed on a beta-cyclodextrin-modified mobile phase. In such a case, the retention times of the polycyclic aromatic hydrocarbons were strongly reduced (e.g. from 127 to 1.2 min for 1,8-dimethylnaphthalene) and were close to the hold-up time of the high-performance liquid chromatography (HPLC) system (0.7 min). Moreover, chiral separation of 1-acenaphthenol optical isomers was observed and the elution order of the enantiomers was determined. Within the steroids group, strong interaction was observed for estradiol and testosterone. The results of cluster analysis indicate that beta-cyclodextrin as well as gamma-cyclodextrin and its hydroxypropyl derivative can be most effective mobile-phase additives under reversed-phase HPLC conditions for 3D-shape-recognition-driven separation, performed at subambient and elevated temperatures, respectively.

Failure of cortisone acetate therapy in 21-hydroxylase deficiency in early infancy.

BACKGROUND: Pediatric endocrinologists initially treat congenital adrenal hyperplasia with either cortisone acetate (CA) or hydrocortisone (HC). Despite high doses of CA, we noted that 17-hydroxyprogesterone (17-OHP) and corticotropin were not fully suppressed in serum from neonates with 21-hydroxylase deficiency (21-OHD) until they were 40- to 80-days-old. In contrast, serum concentrations of 17-OHP were suppressed immediately by oral treatment with HC. METHODS: We sought to understand the reason for this discrepancy. Serum cortisol (F), cortisone (E), and 17-OHP were measured by radioimmunoassay or high-performance liquid chromatography in seven neonates with 21-OHD and in 118 normal subjects. From the time of diagnosis, CA was administered to four of the neonates with 21-OHD, while HC was given to the other three. RESULTS: In normal subjects serum E concentrations were greater than F during the first 2 months after birth, whereas F concentrations exceeded E after 2 months of age. Although infants receiving CA initially were given a high dose, serum F concentrations were extremely low, while 17-OHP concentrations were high until about 2 months of age. Then serum F exceeded E, and 17-OHP became fully suppressed even though infants received only a moderate dose of CA. In contrast, HC administration successfully normalized serum 17-OHP in the neonatal period. With temporary switching of neonates from HC to CA, serum F concentrations immediately decreased and 17-OHP concentrations increased. CONCLUSION: Conversion of E to F may be limited during early infancy, adversely affecting treatment with CA. Cortisone acetate may be inappropriate as a glucocorticoid replacement during early infancy in patients with 21-OHD.

Sample preparation with fiber-in-tube solid-phase microextraction for capillary electrophoretic separation of tricyclic antidepressant drugs in human urine.

Solid-phase microextraction (SPME) is a solvent-free sample preparation technique using a thin coating attached to the surface of a fused silica-fiber as the extraction medium, which has been successfully applied to the analysis of a wide variety of compounds by coupling to gas chromatography (GC). In recent years, in-tube SPME using GC capillary column as the extraction medium has also been developed and coupled with liquid chromatography (LC) for the preconcentration of nonvolatile compounds. In this study, an on-line interface between the fiber-in-tube SPME and capillary electrophoresis (CE) has been developed, and the preconcentration and separation of four tricyclic antidepressant (TCA) drugs, amitriptyline, imipramine, nortriptyline, and desipramine, were performed with the hyphenated system. Under the optimized condition, a better extraction performance than conventional in-tube SPME was obtained, even the length of the extraction medium was much shorter. The results clearly indicated that the fiber was working effectively as an extraction medium. For the separation of these four TCAs, capillary electrophoretic separation with beta-cyclodextrin as the buffer additive has been employed and the application of the developed system to the analysis of complex sample mixtures in a biological matrix is also demonstrated.

[Multimodal treatment including intraoperative irradiation for advanced pancreatic cancer with extended metastasis].

From January 1987 to December 1999, we treated 11 advanced pancreatic cancer patients with extended metastasis with multimodal treatment. Two patients received external radiation therapy (ERT) and systemic chemotherapy, 1 received intraoperative radiation therapy (IORT) and ERT and arterial infusion chemotherapy (AIC), 2 received IORT and AIC, 4 received only IORT, 2 received only AIC, and 15 did not receive any of these treatments. There was a significant difference in the survival rate between treatment and no treatment cases (median survival of 177 days and 109 days, respectively) (p = 0.04). A significant difference in the survival rate was also observed between IORT cases and no treatment cases (median survival of 212 days and 109 days, respectively) (p = 0.02). However, there was no significant difference in the survival rate between AIC cases and no treatment cases (median survival of 177 days and 109 days, respectively) (p = 0.10). Therefore, our experience suggests that multimodal treatment including intraoperative irradiation is effective for advanced pancreatic cancer patients with extended metastasis.

Capillary electrochromatography using fibers as stationary phases.

Fiber-packed capillary columns have been evaluated in chromatographic performance in capillary electrochromatography (CEC). The change of electroosmotic flow (EOF) velocity and selectivity using different kinds of fiber materials was examined. Although the EOF velocity among the different fiber packed columns was almost the same, retention of parabens was larger on the Kevlar-packed column than on the Zylon-packed one, and was larger on the as-span-type fiber-packed column than on the high-modulus-type packed one. Using 200 microm ID x 5 cm Kevlar packed column combined with a 100 microm ID x 20 cm precolumn capillary and a 530 microm ID x 45 cm postcolumn capillary, the separation of three parabens within 30 s was achieved. Other compounds were also separated in a few minutes by the fiber-packed CEC method.

Fibrous stationary phase in capillary electrochromatography.

Capillary electrochromatography (CEC) using fibrous cellulose acetate (CA) stationary phase was investigated. The advantage of this fiber-packed column is relatively easy preparation process compared with other conventional CEC columns, such as particle-packed and wall-coated capillaries. CA fibers are manually packed into a capillary with two guide liners and fixed with a frit at the column inlet. The separation characteristics of this column were investigated using n-alkyl p-hydroxybenzoates (parabens) as the sample probe. It has been demonstrated that the use of a short column length and a specially designed tee-connector as the injection device should make the separation performance and efficiency much higher on the fiber-packed columns. Sufficient separation between methyl and n-butylparabens is obtained on the 5-cm-packed column and linear relationships between the injection time and the peak area are observed. Bubble formation is not encountered during the analysis.

Molecular-dynamics simulation for liquid chromatographic interactions: effect of mobile phase composition.

A molecular-dynamics simulation method has been applied to investigate the influence of the mobile-phase composition on the retention of solutes in HPLC. The distribution profiles of the distance between two atoms in ODS ligands were constructed to characterize the conformation of ODS ligand molecules. The distinct difference of ODS conformation is observed by comparing molecular models consisting of solvent molecules at each solvent composition. The distribution profiles of the distance between the mobile-phase solvent molecules and ODS ligand molecules were also constructed to characterize the distribution of the solvent molecules at each composition. In all distribution profiles, the difference in the distribution due to a change in the solvent compositions was very clearly found, and the facts seem to be very reasonable. The distribution profiles of the distance between the solute, n-propylbenzene, and the terminal carbon atom in the ODS ligand, and between the solute and the silicon atom in the ODS ligand have been also constructed to see the distribution of the solutes in the separation system. The calculated solute distribution in the ODS-methanol/water system is very consistent with the actual chromatographic retention behaviors.

Comparison of separation behavior of benzodiazepines in packed capillary electrochromatography and open-tubular capillary electrochromatography.

Packed column capillary electrochromatography (CEC), open-tubular CEC and microcolum liquid chromatography (LC) using a cholesteryl silica bonded phase have been studied to compare the retention behavior for benzodiazepines. It has been found that packed column CEC gives better resolution, faster analysis time than microcolumn LC for benzodiazepines maintaining similar selectivity except for some solutes which are charged species under the separation conditions. However, open-tubular CEC gave different selectivities to a larger extent for charged benzodiazepines from that which should be produced by the chromatographic properties of the cholesteryl silica phase. Charged species migration times are mainly influenced by electrophoretic mobility rather than the chromatographic interactions.

Fullerenes separation with monomeric type C30 stationary phase in high-performance liquid chromatography.

The temperature effect on the separation of fullerenes in LC was examined using monomeric type C30, C18 and C8 alkyl bonded stationary phases. It appears that the C30 phase exhibits superior separation ability for fullerenes. It is observed that the maximum retention temperature of fullerenes on the C30 phase is around 20 degrees C. A strong correlation between the changes in NMR spectra and the retention behavior of the solutes was found. The interpretation of the retention behavior of fullerenes on the alkyl bonded stationary phases, including the behavior in subambient temperature, is discussed using the information obtained by CP-MAS solid-state NMR spectroscopy and LC.

Direct coupling of microcolumn liquid chromatography with in-tube solid-phase microextraction for the analysis of antidepressant drugs.

The direct coupling of in-tube solid-phase microextraction (in-tube SPME) with microcolumn liquid chromatography (micro-LC) has been investigated for the analysis of antidepressants in human urine. The use of in-tube SPME has been clearly shown to be advantageous for the on-line coupling of the SPME method, as the sample pretreatment technique, with micro-LC as the separation technique. This is because much smaller amounts of the sample solutions, desorption solvents and the mobile phase are required compared with conventional SPME-LC systems. The parameters for preconcentration have been investigated for the extraction capillary with the newly developed 'wire-in-tube' configuration.

Fiber-in-tube solid-phase microextraction: a fibrous rigid-rod heterocyclic polymer as the extraction medium.

A novel "fiber-in-tube" configuration has been applied to the extraction tube of solid phase microextraction (SPME), and the direct coupling of the extraction process to liquid chromatography (LC) has been accomplished for the analysis of n-butylphthalate in wastewater. By using this fiber-in-tube SPME/LC system the preconcentration factor for the phthalate was about 160 with 20 min extraction and no interference peak was observed in the chromatogram. The results also showed the potential applications of this fiber-in-tube SPME/LC for the analysis of sub-ppb level (i.e., lower than 1 ng/mL) of various organic analytes in aqueous sample matrix without a large solvent consumption during the preconcentration process.

Evaluation of endoscopic injection sclerotherapy with and without simultaneous ligation for the treatment of esophageal varices.

For more effective and simple endoscopic injection sclerotherapy (EIS) for esophageal varices, we developed an EIS procedure with ligation (EISL) that is non-invasive, in which EIS and endoscopic variceal ligation (EVL) are performed simultaneously. In this study, we compared EISL and EIS in a randomized sample of patients (n = 14 for each procedure). For EISL, EVL was performed, including the injection site, after the injection of 5% ethanolamine oleate with iopamidol (EOI) into a varix. The mean number of treatment sessions required for eradication of esophageal varices was 2.3+/-0.5 for EISL and 3.9+/-0.8 for EIS (P < 0.001); the mean number of treatment sites was 6.2+/-2.2 for EISL and 14.0+/-5.0 for EIS (P < 0.001); the mean total amount of EOI used was 13.8+/-5.2ml for EISL and 26.3+/-9.8ml for EIS (P < 0.001). There were no significant differences in rates of recurrence of varices or in bleeding between the two groups. For EISL, fewer treatment sessions and less sclerosant were sufficient, probably because the sclerosants were more effective due to the blockage of variceal blood flow by the ligation. This method should provide a novel modification of EIS.

Preparation of capillary columns coated with linear polymer containing hydrophobic and charged groups for capillary electrochromatography.

A linear polymer-coated capillary was prepared by in-capillary copolymerization of N-tert-butylacrylamide (TBAAm) with a charged monomer, 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS), after the capillary pretreatment with a bifunctional reagent. The coated capillaries were applied in capillary electrochromatographic (CEC) separation of small neutral compounds. Hydrophobic groups in the linear polymer, which were immobilized onto the capillary surface, functioned as the stationary phase in reversed-phase CEC separation, and charged groups in the linear polymer generated electroosmotic flow (EOF) along the column. The coated capillaries were prepared by a simple procedure. Moreover, the reproducibility with respect to EOF rate and migration times of the solutes was excellent. The results for CEC separation of small molecules using the linear polymer-coated capillaries are presented.

Measurement and evaluation of serum anti-p53 antibody levels in patients with lung cancer at its initial presentation: a prospective study.

Anti-p53 antibodies in sera are known to be products of the host immune response to mutated p53 protein, and are present in some patients with various types of cancer. In this study, we measured serum anti-p53 antibody levels in 52 patients with lung cancer and 63 normal volunteers to determine the relationship between anti-p53 antibody level and clinical features of lung cancer patients. Anti-p53 antibody level was measured by an enzyme-linked immunosorbent assay and expressed as an anti-p53 antibody index, defined as the ratio of absorption of serum sample to that of p53-positive serum. The median anti-p53 antibody index was 6.6 for lung cancer patients, and higher than that in normal volunteers (1.7) (P = 0.0000). For lung cancer patients, significant differences in index levels were found by histology (4.3, n = 25, adenocarcinoma vs 8.7, n = 18, squamous cell carcinoma vs 64.8, n = 2, large-cell carcinoma vs 9.8, n = 7, small-cell carcinoma; P = 0.0109). High anti-p53 antibody index levels were observed for both large-cell carcinoma and small-cell carcinoma. When the cut-off level was set at 7.2, determined using the twice 95% specificity level for normal volunteers, the sensitivities of anti-p53 antibodies were 46.1% for all lung cancers, 28.0% for adenocarcinoma, 55.6% for squamous cell carcinoma, 100% for large-cell carcinoma and 71.4% for small-cell carcinoma. However, there were no significant differences in index level by gender, age, smoking index, presence of previous or concomitant cancer or disease stage. Multivariate analysis using a logistic regression model demonstrated that histological type of tumour was a dominant factor associated with elevation of anti-p53 antibody index level (P = 0.0184). These findings suggest that serum anti-p53 antibody index level might be independent of tumour burden and the presence of previous or concomitant cancer in our series of lung cancer patients, but is clearly strongly correlated with tumour histological type.

Circulating vascular endothelial growth factor (VEGF) is a possible tumor marker for metastasis in human hepatocellular carcinoma.

Vascular endothelial growth factor (VEGF) is closely related to angiogenesis in various human cancers. However, little is known of its circulating levels in hepatocellular carcinoma (HCC). We examined circulating VEGF levels in chronic liver disease to assess their clinical significance. Plasma VEGF concentrations were determined, by enzyme immunoassay, in patients with chronic hepatitis (CH; n = 36), liver cirrhosis (LC; n = 77), and HCC (n = 86) for a cross-sectional study. Plasma VEGF levels in healthy controls (n = 20) and CH, LC, and HCC patients were 17.7 +/- 5.4 (mean +/- SD), 30.6 +/- 22.8, 34.4 +/- 27.0, and 51.1 +/- 71.9 pg/ml, respectively. The levels were significantly elevated in the HCC group, compared with the control, CH, and LC groups. Plasma VEGF levels in stage I, II, III, IVA, and IVB HCC patients were 27.6 +/- 16.1, 26.5 +/- 13.7, 35.8 +/- 15.3, 45.4 +/- 39.4, and 103.1 +/- 123.2 pg/ml, respectively. The stage IVB patients with remote metastasis showed significantly marked elevation compared with the patients at the other stages. Platelet numbers were weakly correlated with plasma VEGF levels in the HCC group. Plasma VEGF level was highly elevated in patients with HCC, particularly those with metastatic disease. We consider that plasma VEGF is a possible tumor marker for metastasis of HCC. Circulating VEGF may be derived mainly from the large burden of tumor cells, and partly from platelets activated by the vascular invasion of HCC cells.

Separation of benzodiazepines using cholesterol-modified fused-silica capillaries in capillary electrochromatography.

This paper describes the use of cholesteryl-10-undecenoate as a capillary column modifier for capillary electrochromatography. This bonded phase has shown an entirely different selectivity as compared to octadecyl silica (ODS) phases in reversed-phase liquid chromatography, specifically in the analysis of the benzodiazepines. This difference serves as the basis for the continuing study as well as the present focus on electrochromatography as a relatively new separation technique. To significantly increase the surface area, etching of the inner wall of a 75-micron capillary is performed using ammonium hydrogen difluoride and is then subsequently modified via a silation reaction with triethoxysilane and subjected to hydrosilation with cholesteryl-10-undecenoate to form the bonded phase. The performance of this capillary is compared with unetched cholesterol-modified and bare, fused-silica capillaries. Efficient resolution was noted for the etched capillary showing the effectiveness of the etching process as well as the selective property of the bonded phase.