High-performance liquid chromatography determination of phenolic constituents in 17 varieties of cowpeas

Seventeen varieties of cowpeas grown in Arkansas were analyzed for their phenolic constituents using high-performance liquid chromatography (HPLC). Protocatechuic acid was identified as the major phenolic acid present in esterified forms. The amount of protocatechuic acid increased from trace-3.6 to 9.3-92.7 mg/100 g of flour in the 17 varieties of cowpeas after hydrolysis. Six other phenolic acids, including, p-hydroxybenzoic acid, caffeic acid, p-coumaric acid, ferulic acid, 2,4-dimethoxybenzoic acid, and cinnamic acid, were also identified. These phenolic acids were evenly distributed mainly in free acid forms at <7 mg/100 g of flour. Total phenolic contents determined using Folin-Ciocalteu's reagent were largely different among the 17 varieties, ranging from 34.6 to 376.6 mg/100 g of flour. A comparison of the HPLC chromatograms of the 17 cowpea phenolics before and after alkali hydrolysis indicated the conversion of a pattern with evenly distributed peaks to one with a single major peak for protocatechuic acid, suggesting that the chromatograms before hydrolysis better represent the identities of the cowpea varieties.

[Immunohistochemistry research on keratoconus]

PURPOSE

Keratoconus is a noninflammatory disease characterized by thining and ectasia of the central cornea. The etiology and pathogenesis of keratoconus remain unclear. We studied the composition of basement membranes (BM) in normal, scarred and keratconus corneas to find out possible changes specific for keratoconus.

METHODS

Paraffin-embeded sections of normal, scarred and keratoconus corneas were immunostained with antibodys against type IV collagen, Fibronectin (Fn) and Laminin (Ln).

RESULTS

Keratoconus had increased staining of the epithelial BM for alpha 1-alpha 2 chain of type IV collagen and Fn, especially in scarred corneal regions. A similar enhancement was also observed in scarred corneas, and there was no significant difference between keratoconus and scarred cornea.

CONCLUSION

A process similar to wound healing would largely contribute to the differences seen in the keratoconus.

Preparation of bean curds from protein fractions of six legumes

Chickpeas, lentils, smooth peas, mung beans, and faba beans were milled into flours and fractionated to protein and starch fractions. Compositions of the seeds, cotyledons, and flours were compared for each legume and the weight and protein recovery of each fraction analyzed. Bean curds were prepared from the protein fractions through heat denaturation of protein milk, followed by coagulation with calcium sulfate or magnesium sulfate. The effect of chickpea protein concentration and coagulant dosage on the texture of bean curds was evaluated using a texture analyzer. Textural analysis indicated that curd prepared at 2.3-3.0% protein concentration and 1.5% CaSO(4) dosage had better yield and better texture than curds prepared under other conditions. Bean curds prepared from chickpeas and faba beans exhibited the second highest springiness and cohesiveness after those from soybeans. Curds of mung beans and smooth peas, on the other hand, had the highest yields and the highest moisture contents. The protein yield of the first and second soluble extracts used for curd preparation accounted for approximately 90% of the total protein of the seeds.

Mammalian histone deacetylase 1 protein is posttranslationally modified by phosphorylation

HDAC1, a member of the histone deacetylase family, is involved in transcription regulation through the modification of chromatin structure. Several studies also implicated HDAC1 in tumorigenesis. Much attention has been concentrated on protein-protein interactions involving HDAC1 and the possibility that posttranslational modifications may occur in mammalian HDAC1 proteins has not been carefully and systematically investigated. In this study, we utilized in vivo labeling assays to demonstrate that both human and murine HDAC1 proteins are phosphorylated in cells. Assays using HDAC1 deletion mutants indicated that phosphorylation occurs in its C-terminal domain. cAMP-dependent kinase and casein kinase II, but not protein kinase C, cdc2, or MAP kinase, could phosphorylate HDAC1 in vitro, although HDAC1 contains several protein kinase C consensus sites. We also found that phosphorylation did not influence HDAC1 enzymatic activity using a human histone H4 N-terminal peptide as the substrate. Interestingly, HDAC1-FLAG fusion protein immunoprecipitated from transfected cells was found to be in association with a kinase activity, providing an in vitro assay for further studies of this posttranslational modification.

Error-compensated kinetic determinations by detecting the reagent in successive reactions

An error-compensated algorithm based on detecting the reagent in successive reactions is proposed. The algorithm was first studied by using simulated data and it was found that it performed well in compensating for the system error and eliminating random noise. Then the algorithm was examined by applying it to the determination of epinephrine and norepinephrine under different experimental conditions. The results revealed that the algorithm compensated errors produced not only by the changes of rate constants, but also by the variation of equilibrium signals.

[Production of herbicide-resistant rice with transforming heterogene]

Using pAHC20 (containing Bar gene), pWRG1515 (containing GUS gene and hygromycin phosphotransferase gene), and pCAMBIA3300 RG with Bar gene and snowdrop lectin (GNA) gene as donor DNA, the micro-adventitious shoots and the calli induced from mature embryos of Oryza sativa 87203, Eyi105, Shangnong aromatic glutinous rice as recipients were transformed with particle bombardment and Agrobacterium tumefaciens strain LBA4404 containing pAL4404, respectively. After chosen with phosphinothricin and antibiotic, GUS detection and PCR analysis, The results showed that the foreign genes had been transformed microprojectile-mediated to Oryza sativa Eyi105, the regeneration plants were obtained, and, 5 transgenic calli of Oryza sativa Eyi105 were obtained with Agrobacterium-mediated transformation.

Sensory fibers of the pelvic nerve innervating the Rat's urinary bladder

Much attention has been given to the pelvic nerve afferent innervation of the urinary bladder; however, reports differ considerably in descriptions of afferent receptor types, their conduction velocities, and their potential roles in bladder reflexes and sensation. The present study was undertaken to do a relatively unbiased sampling of bladder afferent fibers of the pelvic nerve in adult female rats. The search stimulus for units to be studied was electrical stimulation of both the bladder nerves and the pelvic nerve. Single-unit activity of 100 L(6) dorsal root fibers, activated by both pelvic and bladder nerve stimulation, was analyzed. Sixty-five units had C-fiber and 35 units had Adelta-fiber conduction velocities. Receptive characteristics were established by direct mechanical stimulation, filling of the bladder with 0.9% NaCl at a physiological speed and by filling the bladder with solutions containing capsaicin, potassium, or turpentine oil. The majority (61) of these fibers were unambiguously excited by bladder filling with 0.9% NaCl and were classified as mechanoreceptors. All mechanoreceptors with receptive fields on the body of the bladder had low pressure thresholds (</=10 mmHg). Receptive fields of units with higher thresholds were near the ureterovesical junction, on the base of the bladder or could not be found. Neither thresholds nor suprathreshold responses could be related to conduction velocity. Bladder compliance and mechanoreceptor thresholds were influenced by the stage of the estrous cycle: both were lowest in proestrous rats and highest in metaestrous rats. Mechanoreceptors innervating the body of the bladder and the region near the ureterovesical junction showed two patterns of responsiveness to slow bladder filling. One group of units exhibited increasing activity with increasing pressure up to 40 mmHg, while the other group showed a peak in activity at pressures below 40 mmHg followed by a plateau or decrease in activity with increasing pressure. It is proposed that differences in stimulus transduction relate to the different response patterns. Thirty-nine units failed to respond to bladder filling. Eight of these were excited by intravesical potassium or capsaicin and were classified as chemoreceptors. The remaining 31 units were not excited by any stimulus tested. Chemoreceptors and unexcited units had both Adelta and C afferent fibers. We conclude that the pelvic nerve sensory innervation of the rat bladder is complex, may be sensitive to hormonal status, and that the properties of individual sensory receptors are not related in an obvious manner to the conduction velocity of their fibers.

Study of the fluorescence characteristics of norfloxacin in reversed micelles and application in analysis

The fluorescence characteristics of norfloxacin (NFLX) were studied in reversed micelles which formed with sodium bis(2-ethylhexyl) sulfosuccinate (AOT)-water-octane. The influences of the environmental factors, such as the water content, AOT concentration and pH, on the fluorescence of NFLX were investigated. A novel spectrofluorimetric method for the direct determination of NFLX is proposed based on the enhancement effect of reversed micelles on the native fluorescence of NFLX, which showed a much lower detection limit (0.0032 microgram mL-1) and a wider linear range (0.015-3.8 micrograms mL-1) compared with aqueous solution.

Study on three-dimensional fluorescent spectral characteristics of fluoroquinolones in varying media

Behaviors of fluoroquinolones in varying media were observed by employing their intrinsic fluorescence. Spectral characteristics in reversed micelles (Aerosol OT/n-octane) were compared with those in aqueous solution and micelles (sodium dodecyl sulfonate). Those differences in interactions between fluoroquinolones and the various media were clearly illustrated by three-dimensional fluorescent spectra. The influences of other environmental factors on spectral characteristics (pH, SDS concentration, etc.) were also investigated.

Lack of association between a biallelic polymorphism in the adducin gene and blood pressure in whites and African Americans

Population-based candidate gene association analyses are becoming increasingly popular as a result of a greater number of genes and gene polymorphisms having been identified for which some functional information is available. Because many biochemical and physiologic systems impact blood pressure regulation and hypertension susceptibility, many of these identified genes and polymorphisms are candidates for population-level association studies involving blood pressure levels or hypertension status. Recent studies have suggested that the alpha-adducin gene may harbor polymorphisms that influence blood pressure level. Therefore, we embarked on a study to test one such polymorphism in two large US samples: one from an urban African American population (Maywood, IL) and another from a rural white population (Tecumseh, MI). We used both family-based association tests and tests that consider the impact of additional measured factors beyond adducin gene variation on blood pressure levels. We found no evidence for a significant effect of the chosen adducin polymorphism on blood pressure variation in either sample. We also found no association between Adducin genotypes and antihypertensive use. These facts, together with similar findings in companion studies, suggest that the alpha-adducin gene polymorphism does not have a pronounced effect on blood pressure variation in the populations studied. This does not suggest, however, that the alpha-adducin gene does not have a role in blood pressure regulation and hypertension susceptibility.

[Photoluminescence study of star-like C60(CH3)x(PAN)x copolymer]

Thin film of new synthesized C60(CH3)x(PAN)x copolymer was fabricated by physical jet deposition (PJD) technique. C60 molecule lies in the center of the star-like copolymers. PAN main chain is modified around the C60 molecules. Absorption and photoluminescence spectra show that there are strong interaction between C60 molecule and PAN, which depends on the length of PAN chain. Partly excitation transfer process between C60 molecule and PAN was observed, which leads to the fluorescence quenching of the PAN.

[Experimental study of lymph node flap transplantation for treatment of lymphedema]

OBJECTIVE

We investigated the treatment of lymphedema by using lymph node flap.

METHODS

Upper limbs' lymphedema model in 14 rabbits were divided into two groups. They were treated with lymph node flap transplantation and general flap transplantation.

RESULTS

Lymph node transplantation can reduce lymphedema and general flap transplantation can not significantly reduce lymphedema.

CONCLUSION

Lymph node flap can be used to treat extremity's lymphedema.

HIV-I TAT inhibits PKR activity by both RNA-dependent and RNA-independent mechanisms

Replication of the human immunodeficiency virus type 1 (HIV-1) is inhibited by interferons (IFNs), in part through activity of the IFN-inducible protein kinase PKR. To escape this antiviral effect, HIV-1 has developed strategies for blocking PKR function. We have previously shown that the HIV-1 Tat protein can associate with PKR in vitro and in vivo and inhibit PKR activity. Here we present evidence that Tat can inhibit PKR activity by both RNA-dependent and RNA-independent mechanisms. Tat inhibited PKR activation by the non-RNA activator heparin, and also suppressed PKR basal level autophosphorylation in the absence of RNA. However, when Tat and dsRNA were preincubated, the amount of Tat required to inhibit PKR activation by dsRNA depended on the dsRNA concentration. In addition to its function in vitro, Tat can also reverse translation inhibition mediated by PKR in COS cells. The Tat amino acid sequence required for interaction with PKR was mapped to residues 40-58, overlapping the hydrophobic core and basic region of HIV-1 Tat. Alignment of amino acid sequences of Tat and eIF-2alpha indicates similarity between the Tat-PKR binding region and the residues around the eIF-2alpha phosphorylation site, suggesting that Tat and eIF-2alpha may bind to the same site on PKR.

[Observation of special stain and ultrastructure of lattice, granular and macular corneal dystrophy]

OBJECTIVE

To investigate the histopathological changes of lattice, granular and macular corneal dystrophy.

METHODS

Corneal buttons were obtained from penetrating keratoplasty due to severe corneal dystrophy, and their sections and ultrathin sections with several special stains were observed under a light microscope (LM) and electron microscope (EM).

RESULTS

In cases with lattice dystrophy, the stromal fusiform deposits seen under LM were confirmed to be amorphous materiel with filaments by EM and stained positively for Masson trichrome, PAS and Congo red. In cases with granular dystrophy, the granular or bread debris deposits found between laminae under LM were extracellular material observed by EM and they were stained positively for Masson trichrome and alcian blue. In cases with macular dystrophy, the stromal spheroid or macular deposits were seen under LM, and there were numerous vacuoles containing fibrils and granules in the cytoplasm of keratocytes and accumulative amorphous material in the stroma under EM; the deposits were positive for colloidal iron and alcian blue stain.

CONCLUSION

In corneal lattice dystrophy, there are amyloid deposits; in granular dystrophy, there are extracellular material deposits; and in macular dystrophy, there is mucopolysaccharide accumulation.

[Effects of Dexamethasone, Fluorometholone and Florex on intraocular pressure after photorefractive keratectomy]

To evaluate the results of elevated intraocular pressure (IO) secondary to dropping of 0.1% Dexamethasone, Fluorometholone and Florex for 1-3 months after photorefractive keratectomy, we summed up and analysed the 3-month follow-up data on 546 eyes in three groups. The rates of IO elevated in Dexamethasone, Fluorometholone and Florex were 36%, 12.4% and 31.9% respectively. After topical use of corticosteroid, some of the elevations of IO took place as early as two weeks, but most of them occurred around 1 month. Eleven patients with IO elevation of both eyes had visual acuity decreased associated with eye-ache and halos and the other patients had no symptoms. After discontinuation of corticosteroid and institution of antiglaucoma therapy, the IO became normal in 3-7 days. In practice, this means that patients receiving corticosteroid eyedrops for more than two weeks should be checked for the possibility of ocular hypertension to prevent the corticosteroid glaucoma.

Effects of fibroblast-mediated interleukin 3 and interleukin 6 gene therapy on hematopoiesis in mice treated with 5-fluorouracil

Fibroblast-mediated cytokine gene therapy has proven to be a promising strategy for restoring hematopoiesis following repeated chemotherapy. Interleukin 3 (IL-3) and interleukin 6 (IL-6) can synergistically promote the recovery of hematopoiesis following chemotherapy. In this investigation, combined use of fibroblast-mediated IL-3 and IL-6 gene therapy was tested for hematopoietic effects on mice with or without 5-fluorouracil administration. The results demonstrated that combined therapy with IL-3 gene-modified NIH3T3 cell (NIH3T3-IL-3) and IL-6 gene-modified fibroblast NIH3T3 cell (NIH3T3-IL-6) implantation achieves obvious stimulation of hematopoiesis in normal mice and accelerates recovery of hematopoiesis. In normal mice the quantities of platelets, neutrophils, and total white blood cells in peripheral blood increased significantly after the combined implantation of NIH3T3-IL-3 and NIH3T3-IL-6 cells. The numbers of colony-forming unit (CFU) granulocyte/macrophage (CFU-GM) and CFU megakaryocyte (CFU-MK) formed by stem cells in bone marrow was significantly higher after the combined implantation of NIH3T3-IL-3 and NIH3T3-IL-6 cells than after the implantation of NIH3T3-IL-3 alone, NIH3T3-IL-6 alone, or neomycin gene-modified NIH3T3 cells. In hematopoiesis-depressed mice induced by preinjection with 5-fluorouracil at the dose of 150 mg/kg before cell implantation, the platelets, neutrophils, and white blood cells showed accelerated recovery, and the numbers of CFU-GM and CFU-MK formed by bone marrow cells were also markedly higher after the combined implantation of NIH3T3-IL-3 and NIH3T3-IL-6 cells than in control groups. Our data show that combined use of fibroblast-mediated IL-3 and IL-6 gene therapy may be of clinical relevance for the recovery of hematopoietic depression for patients after chemotherapy.

[Effects of 764-3 on collagen deposition in hypertensive pulmonary arteries in hypoxic rats]

OBJECTIVE

To investigate the changes of collagen deposition in pulmonary arteries in chronic hypobaric hypoxic rats and the roles of 764-3.

METHODS

Wistar rats were divided into 10 groups. The hypoxic (50.7 kPa) rats were treated with 764-3 (20 mg/kg, once daily) and beta-aminopropionitrile (BAPN, 150 mg/kg, twice daily), respectively. At the end of treatment, the hemodynamic morphological and chemical parameters were measured.

RESULTS

Comparing with the normals, hydroxyproline (HYP) content of extrapulmonary artery (EPA) increased obviously in hypoxic rats, the smooth muscle cells (SMC) in the media of muscular intra-acinar pulmonary artery showed hypertrophy with change in phenotype, and a striking increment of collagen accumulation (P < 0.001); 764-3 could reduce HYP content of EPA (P < 0.05-0.001), and most of SMC in the media became thin and elongated with reversion of change of SMC phenotype, and collagen accumulation was reduced (P < 0.001). In addition, BAPN was more effective than 764-3 (P < 0.05).

CONCLUSIONS

Excessive collagen accumulation in pulmonary arteries plays an important role in the maintenance of hypoxic pulmonary hypertension. 764-3 can partially inhibit collagen deposition in pulmonary arteries, attenuate hypoxic pulmonary hypertension, and has a moderate influence on collagen deposition in compared with BAPN.

[Effects of an extract of salviae miltiorrhizae (764-3) on structural remodeling of intra-acinar pulmonary artery in pulmonary hypertension due to chronic hypoxia and monocrotaline in rats]

OBJECTIVE

To investigate the effects of an extract of salviae miltiorrhizae (764-3) on the percentage of intra-acinar muscular artery (MA), partal MA(PMA) and nonmuscular MA(NMA) and collagen deposition in the media of MA in rats with hypoxia and MCT-induced pulmonary hypertension.

METHOD

Wistar rats were divided into 12 groups. The hypobaric hypoxic 51 kPa (1 kPa = 7.5 mmHg) and MCT (60 mg/kg intraperitoneal injection) rats were treated with 764-3 (20 mg/kg), beta-aminopropionitrile (BAPN, 150 mg/kg) and 764-3 (40 mg/kg), respectively. At each time point, the hemodynamic and morphological parameters were measured.

RESULT

After hypoxia for 2 weeks, the percentage of MA increased (P < 0.001), of NMA decreased (P < 0.001) and of PMA no obvious change; and after 4 weeks, the above changes became to be more striking and the collagen content in the media of MA increased (P < 0.001). The MCT-treated rats had more severe changes than the hypoxic rats. Both 764-3 and BAPN could inhibit the changes, decreased the collagen content and BAPN was more effective than 764-3(P < 0.05).

CONCLUSION

764-3 can partially inhibit collagen deposition in pulmonary arterioles attenuate hypoxia and MCT-induced pulmonary hypertension, reduce the percentage of MA, and has a moderate influence on collagen deposition as compared with BAPN.

Mutations in the double-stranded RNA-activated protein kinase insert region that uncouple catalysis from eIF2alpha binding

The interferon-induced, double-stranded RNA (dsRNA)-activated protein kinase, PKR, inhibits protein synthesis via phosphorylation of the alpha subunit of the translation initiation factor eIF2. A kinase insert region N-terminal of PKR kinase subdomain V, which is conserved among eIF2alpha kinases, has been proposed to determine substrate specificity of these kinases. To investigate the function of this kinase insert region, selective PKR mutants were generated, and kinase activities and eIF2alpha affinities were analyzed in vitro. The in vivo function was investigated by growth inhibitory assays in yeast and translational assays in COS cells. Among the 13 mutations, 5 lost kinase activity and 3 exhibited less than 30% of wild-type eIF2alpha binding activity. The deletion of the conserved sequence (amino acids 362-370) resulted in a protein that had no kinase activity and only about 25% of wild-type eIF2alpha binding, suggesting that this sequence is not only required for PKR kinase activity but also is important for substrate interaction. It was determined that the hydrophobicity of the conserved sequence of PKR is required for kinase activity but is not crucial for eIF2alpha binding. The amino acid residue Glu-367 in the conserved motif was shown to be directly involved in substrate binding but was not important for kinase activity. These results suggest that the activation of PKR is not a prerequisite for its binding to the substrate and that the conserved motif in subdomain V contributes to the interaction of PKR and eIF2alpha.