Quantification of urine 17-ketosteroid sulfates and glucuronides by high-performance liquid chromatography-ion trap mass spectroscopy

The measurement of androgen steroids has been utilized as a clinical indicator of adrenal function, androgen abuse, and as a prediction of general health or biological aging. An improved high-performance liquid chromatography-ion trap mass spectroscopic method with sonic spray ionization (SSI) technology for the quantification of individual urinary 17-ketosteroid sulfates and glucuronides was developed and validated. Sample preparation was simplified using a C18 cartridge followed by direct injection onto a reversed-phase HPLC column. Individual 17-ketosteroid from 63 urinary specimens collected in a 24-h period was measured. 17-Ketosteroid conjugates, total 17-KS-S and the ratio of total 17-KS-S to creatinine referred to herein as the Anabolic/Catabolic Index (ACI) showed statistically significant negative correlations with age.

[Clinical effect of Xinqingning combined low dose continuous gastrointestinal dialysis in treating uremia]

OBJECTIVE

To investigate the clinical effect of Xinqingning (XQN), a preparation of rhubarb, combined with low dose continuous gastrointestinal dialysis in treating uremia.

METHODS

Patients of uremia were divided into three groups at random, eighteen patients in the group A were treated with 1000 ml gastrointestinal dialysate (non-absorbed mannitol solution) orally 2-3 times a day, twenty patients in the group B treated with the same therapy as that in the group A, but combined with XQN 5-10 tablets 3 times per day and 19 patients in the group C treated by orally taken coated aldehyde oxystarch 5-10 g, 3 times a day. The therapeutic course for the three groups were 11 months. The changes in clinical manifestation, renal function, nutritional condition, and electrolytes before and after treatment were observed.

RESULTS

After treatment, significant improvement was revealed in aspects of uremic symptoms, quality of life, nutritional condition, serum creatinine, urea nitrogen, serum phosphate, uric acid, CO2 combining power, creatine clearance, body weight and arm muscular circumference in the group A and B, as compared with those in the group C. In comparison of the group A and B, the group B showed a lower serum triglyceride and slower progression of chronic renal failure (CRF). All the criteria were not improved in the group C and with serum creatinine raised significantly.

CONCLUSION

XQN combined low dose continuous gastrointestinal dialysis therapy was effective in definitely treating uremia, it provides a new therapeutic means of non-replacement therapy for CRF with uremia.

[Modern spectral estimation of ICP-AES]

The inductively coupled plasma atomic emission spectrometry (ICP-AES) and its signal characteristics were discussed using modern spectral estimation technique. The power spectra density (PSD) was calculated using the auto-regression (AR) model of modern spectra estimation. The Levinson-Durbin recursion method was used to estimate the model parameters which were used for the PSD computation. The results obtained with actual ICP-AES spectra and measurements showed that the spectral estimation technique was helpful for the better understanding about spectral composition and signal characteristics.

Modified Aloe barbadensis polysaccharide with immunoregulatory activity

Aloe barbadensis polysaccharide was partially digested with cellulase and further purified by dialysis, stepwise ethanol precipitation, and size exclusion chromatography. Crude modified Aloe polysaccharide (MAP) activated macrophage cells and stimulated fibroblast growth. Under the same conditions, native Aloe barbadensis gel had no effect on macrophage activation. MAP prevented ultraviolet B (UVB) irradiation-induced immune suppression as determined by contact hypersensitivity (CHS) response in C3H/HeN mice. This in vivo activity was correlated with the activity of MAP to inhibit UVB irradiation-induced tumor necrosis factor alpha (TNF-alpha) release from human epidermoid carcinoma cells (KB cells). MAP with an average molecular weight of 80,000 Dalton (Da) contained mannose, galactose, and glucose in a ratio of 40:1.4:1.0. MAP was likely a linear, highly acetylated molecule.

Clinical study of orthokeratology in young myopic adolescents

This project was designed to study the efficacy of orthokeratology and its related problems in a population of young myopic adolescents. Fifty-four young myopia adolescents ages 11 to 15 years were enrolled in the study and followed over a 6-month period. The procedures included (1) baseline refraction, assessment of tear quality and quantity, and cornea examination including cornea topography, A-scan ultrasound of cornea thickness, and spectromicroscopy of the corneal endothelium; (2) diagnostic lens fitting and evaluation; (3) lens dispensing and educating the patients or their parents; (4) follow-up schedule and data analysis; and (5) maintenance lens dispensing and analysis of wearing schedules. Myopia was reduced between -1.25 and -5.00 D (-3.00 D average). Myopia reduction was almost complete in the first 6 months, with most of the reduction occurring during the first 2 weeks. Seventy-five percent of the possible reduction occurred during this 2-week time period. Tear quality and quantity influenced reduction speed and amount. Corneal thickness and endothelium remained unchanged over the study period. Subjective refraction is the most reliable method to measure the status of ocular refractive changes. Corneal staining occurred in 45% of subjects during the procedure, mainly in subjects with tear problems. Eighteen percent of the subjects showed induced astigmatism, which could be reversed by refitting the lens or changing the wearing schedule. Maintenance lenses had to be worn every night for young adolescents to maintain myopia reduction. Orthokeratology is a reliable option for reducing some myopia in young adolescents. The first 2 weeks are critical for the procedure. Complete examination and the data analysis procedures are important for monitoring prognosis and eye health.

[Influence of different total parenteral nutrition support upon hepatic regeneration after partial hepatectomy in rats]

This study was designed to investigate the effects of different TPN on liver regeneration after partial hepatectomy in rats. Forty Wistar rats were randomly divided into four groups. Groups A and B (normal rats) received BCAA-enriched TPN (45% BCAAs) and standard TPN (24% BCAAs) respectively after 34% hepatectomy; Groups C and D (rats with cirrhosis of liver) received the same TPN as Groups A and B received respectively after 34% hepatectomy. On the third day after operation, all rats were killed and specimens of liver and blood were taken for measurement of activity of liver regeneration. The results showed that DNA synthesis rate and mitosis rate in Groups A and B were significantly greater than those in Groups C and D respectively; RLR, DNA synthesis rate and mitosis rate in Groups A and C were significantly higher than those in Groups B and D respectively. These suggest that the effect of the same TPN on liver regeneration in normal rats is better than that in cirrhosis rats and that BCAA-enriched TPN can provide more excellent supplementation than standard TPN can do either in normal liver or cirrhosis liver after partial hepatectomy.

Isolation and molecular characterization of a poliovirus type 1 mutant that replicates in the spinal cords of mice

The Mahoney strain of poliovirus type 1 (OM) is generally unable to cause paralysis in mice. We isolated a mouse-adapted mutant, PV1/OM-SA (SA), from the spinal cord of a mouse that had been intracerebrally inoculated with OM. SA showed mouse neurovirulence only with intraspinal inoculation, and the infected mice developed a flaccid paralysis, which was indistinguishable from that observed in poliovirus-sensitive transgenic mice inoculated with OM. SA antigens were detected in neurons of the spinal cords of the infected mice. Nucleotide (nt) sequence analysis revealed 9 nt changes on the SA genome, resulting in three amino acid (a.a.) substitutions, i.e., one each in the capsid proteins VP4 and VP1 and in the noncapsid protein 2C. To identify the key mutation site(s) for the mouse neurovirulence, virus recombinants between OM and SA were constructed by using infectious cDNA clones of these two viruses and tested for their mouse neurovirulence after inoculation via an intraspinal route. The results indicated that a mutation at nt 928 (replacement of A with G), resulting in a substitution of Met for Ile at a.a. 62 within VP4, was responsible for conferring the mouse neurovirulence phenotype of the mutant SA. The mutation in VP4 may render the virus accessible to a molecule that acts as a virus receptor and is located on the surfaces of neurons of the mouse spinal cord. This molecule appears not to be expressed in the mouse brain.

Pikuroside: a novel iridoid from Picrorhiza kurroa

A new iridoid, pikuroside (1), was isolated from the roots of Picrorhiza kurroa, together with three known iridoids, picroside I (2), picroside II (3), and 6-feruloyl catalpol (4). The structure of 1 was established by interpretation and full assignments of NMR spectral data. Pikuroside (1) had no antiinflammatory activity, although the crude extract and picroside II (3) demonstrated moderate activity.

Structure-activity relationships: analogues of the dicaffeoylquinic and dicaffeoyltartaric acids as potent inhibitors of human immunodeficiency virus type 1 integrase and replication

The dicaffeoylquinic acids (DCQAs) and dicaffeoyltartaric acids (DCTAs) are potent and selective inhibitors of human immunodeficiency virus type 1 (HIV-1) integrase. They also inhibit HIV-1 replication at nontoxic concentrations. Since integrase is an excellent target for anti-HIV therapy, structure-activity relationships were employed to synthesize compounds with: (1) improved potency against HIV-1 integrase, (2) improved anti-HIV effect in tissue culture, and (3) increased selectivity as indicated by low cellular toxicity. Thirty-four analogues of the DCTAs and DCQAs were synthesized and tested for cell toxicity, anti-HIV activity, and inhibition of HIV-1 integrase. Seventeen of the 34 analogues had potent activity against HIV-1 integrase ranging from 0. 07 to >10 microM. Seventeen analogues that were synthesized or purchased had no inhibitory activity against integrase at concentrations of 25 microM. Of the biologically active analogues, 7 of the 17 inhibited HIV replication at nontoxic concentrations. The most potent compounds were D-chicoric acid, meso-chicoric acid, bis(3,4-dihydroxydihydrocinnamoyl)-L-tartaric acid, digalloyl-L-tartaric acid, bis(3,4-dihydroxybenzoyl)-L-tartaric acid, dicaffeoylglyceric acid, and bis(3, 4-dihydroxyphenylacetyl)-L-tartaric acid. Anti-HIV activity of the active compounds in tissue culture ranged from 35 to 0.66 microM. Structure-activity relationships demonstrated that biscatechol moieties were absolutely required for inhibition of integrase, while at least one free carboxyl group was required for anti-HIV activity. These data demonstrate that analogues of the DCTAs and the DCQAs can be synthesized which have improved activity against HIV integrase.

[Effects of fat emulsion on serum lipid, apo A I, apo B100, LCAT, KBR of postoperative patients with liver disorder]

Twenty post-operative patients with liver disorder were divided randomly into two groups. Ten of them received mean 0.82 g.kg-1.d-1 fat emulsion(42% of the total calorie), and the other ten received mean 1.72 g.kg-1.d-1 fat emulsion (52% of the total calorie) via vein during 5 post-operative days. Their serum lipid, apoA I, apoB100, ketone body ratio (KBR), fat clearance, LCAT and so on were investigted. The results suggest that it is safe for liver-disordered patients with slight or even moderate abnormality of liver function to receive mean 0.82 g.kg-1.d-1 and 1.72 g.kg-1.d-1 fat emulsion after operation and the use of mean 1.72 g.kg-1.d-1 fat emulsion will do no harm but good to liver function.

[Intracardiac operations performed in beating heart through mini-thoracotomy in 34 patients]

OBJECTIVE

To introduce the technique of intracardiac operations performed in beating heart through mini-thoracotomy.

METHOD

>From March 1995 to June 1997, intracardiac operations were performed in beating heart through right subaxillary anterolateral mini-thoracotomy with normothermic extracorporeal circulation in 34 patients. 16 patients had atrial septal defect, 14 ventricular septal defect, 2 mitral insufficiency, 1 right coronary artery-right ventricular fistula, and 1 Ebstein's anomaly.

RESULT

The mean cardiopulmonary bypass time was 22.54 minutes. There were no embolism, arrhythmia and cerebral complications. Postoperative hospital stay was 8.0 +/- 2.2 days. All the patients had no heart murmur and residual shunt, and enjoyed a full range of physical activities in a follow-up of 2 to 26 months.

CONCLUSION

Intracardiac operations performed in beating heart through right subaxillary anterolateral mini-thoracotomy appears to be less invasive, simple, safe and cosmetic.

[Cardiac operation via subaxillary and anterolateral subaxillary thoracotomy with cardiopulmonary bypass]

From March 1995 to August 1996, 50 patients underwent cardiac operation through subaxillary and anterolateral subaxillary thoracotomy with cardiopulmonary bypass. 17 had atrial septal defect, 26 ventricular septal defect, 3 mitral stenosis and insufficiency, 1 isolated mitral insufficiency, 1 double chamber of right ventricle, 1 partial common atrioventricular canal, and 1 cor atriatriatum. All operations were successfully performed without technical difficulty. The cardiopulmonary bypass time was 40.19 +/- 17.17 minutes with aortic cross-clamping time of 22.59 +/- 11.06 minutes. There were no operative death and complications. In conclusion, the subaxillary and anterolateral subaxillary thoracotomy incision appears to be a minimally invasive, safe, effective and cosmetic alterative to median sternotomy for cardiac operation.

Dicaffeoylquinic acid inhibitors of human immunodeficiency virus integrase: inhibition of the core catalytic domain of human immunodeficiency virus integrase

Integration of a cDNA copy of the human immunodeficiency virus (HIV) genome is mediated by an HIV-1-encoded enzyme, integrase (IN), and is required for productive infection of CD4+ lymphocytes. It had been shown that 3,5-dicaffeoylquinic acid and two analogues were potent and selective inhibitors of HIV-1 IN in vitro. To determine whether the inhibition of IN by dicaffeoylquinic acids was limited to the 3,5 substitution, 3,4-, 4,5-, and 1,5-dicaffeoylquinic acids were tested for inhibition of HIV-1 replication in tissue culture and inhibition of HIV-1 IN in vitro. All of the dicaffeoylquinic acids were found to inhibit HIV-1 replication at concentrations ranging from 1 to 6 microM in T cell lines, whereas their toxic concentrations in the same cell lines were > 120 microM. In addition, the compounds inhibited HIV-1 IN in vitro at submicromolar concentrations. Molecular modeling of these ligands with the core catalytic domain of IN indicated an energetically favorable reaction, with the most potent inhibitors filling a groove within the predicted catalytic site of IN. The calculated change in internal free energy of the ligand/IN complex correlated with the ability of the compounds to inhibit HIV-1 IN in vitro. These results indicate that the dicaffeoylquinic acids as a class are potent and selective inhibitors of HIV-1 IN and form important lead compounds for HIV drug discovery.

A dynamic and quantitative study of pattern visual evoked potentials and gamma-aminobutyric acid neurones in the lateral geniculate nucleus and the visual cortex of monocular deprivation cats

PURPOSE

To assess the effects of monocular lid closure during critical period on cortical activity.

METHOD

Pattern visual evoked potentials (PVEP) of the normal and the monocular deprivation (MD) cats were dynamically measured and the number of gammaaminobutyric acid immunopositive (GABA-IP) neurones of the area 17 of the visual cortex and the lateral geniculate nucleus (LGN) was quantitatively compared by using immunohistochemical method (ABC).

RESULTS

The amplitude of the N1-P1 attenuated in deprived eyes (DE), NE/DE at postnatal week (PNW) 7-8 (P < 0.05), NE/DE at PNW 15-16 (P < 0.01); while P1 latency delayed, NE/DE at PNW 7-8 (P > 0.05), NE/DE at PNW 15-16 (P< 0.05). The numbers of GABA-IP neurones in layer A1 of the ipsilateral LGN and in layer A of the contralateral LGN, compared to those in the corresponding normal laminae, were not significant at PNW 7-8 and PNW 11-12 (P > 0.05), while in the same cats a reduction in the number of GABA-IP neurones was found in layer IV of area 17 at PNW 11-12 (P < 0.05). However, with longer survival of 3-4 weeks in duration, the numbers of GABA-IP neurones in the deprived laminae of LGN were remarkably reduced (P < 0.05).

CONCLUSIONS

The amplitude of N1-P1 components is sensitive to the effects of monocular deprivation. Monocular deprivation in cats during critical period leads to dramatic changes of the number of GABA-IP neurones in the LGN and cortical layer IV receiving inputs from the deprived eye in cats. The deprivation-induced reduction in GABA-IP neurones is delayed in the LGN compared with the visual cortex. PVEP of the MD cats is consistent with the damage of its GABA system in visual cortex.

Inhibitors of HIV-1 replication [corrected; erratum to be published] that inhibit HIV integrase

HIV-1 replication depends on the viral enzyme integrase that mediates integration of a DNA copy of the virus into the host cell genome. This enzyme represents a novel target to which antiviral agents might be directed. Three compounds, 3,5-dicaffeoylquinic acid, 1-methoxyoxalyl-3,5-dicaffeoylquinic acid, and L-chicoric acid, inhibit HIV-1 integrase in biochemical assays at concentrations ranging from 0.06-0.66 microgram/ml; furthermore, these compounds inhibit HIV-1 replication in tissue culture at 1-4 microgram/ml. The toxic concentrations of these compounds are fully 100-fold greater than their antiviral concentrations. These compounds represent a potentially important new class of antiviral agents that may contribute to our understanding of the molecular mechanisms of viral integration. Thus, the dicaffeoylquinic acids are promising leads to new anti-HIV therapeutics and offer a significant advance in the search for new HIV enzyme targets as they are both specific for HIV-1 integrase and active against HIV-1 in tissue culture.

Drug leads from the Kallawaya herbalists of Bolivia. 1. Background, rationale, protocol and anti-HIV activity

Aqueous, organic and alcoholic extracts of over 100 samples of 60 species of Kallawaya medicinal herbs representing 30 plant families were assayed to compare their toxicity and ability to protect MT-2 T-lymphoblastoid cells from the cytopathic effect of human immunodeficiency virus (HIV). The results are reported as a therapeutic index (TI) which was > 25 for eighteen species, including seven > 50 and one > 100. The anti-HIV activity resided primarily in the aqueous rather than in the organic extracts and was concentrated in plants used in ethnomedicine to treat lung and liver diseases.

The Grb2 binding domain of mSos1 is not required for downstream signal transduction

Cellular Ras proteins are activated primarily by specific guanine-nucleotide releasing factors such as the Son of Sevenless (Sos) proteins. This activation event is thought to occur in response to plasma membrane localization of a complex containing Sos and a small adapter protein Grb2. We have isolated a dominant mutant allele of mSos1 which transforms Rat1 cells, yet is no longer able to bind Grb2. Biochemical experiments reveal that the subcellular distribution of this truncated Sos protein is not altered with respect to the wild type Sos protein. These data argue against a role for Grb2 in the direct recruitment of Sos proteins to the plasma membrane and suggest that Grb2 may function to overcome negative regulation of Sos by its C terminus.

Vascular endothelial cell growth factor promotes tyrosine phosphorylation of mediators of signal transduction that contain SH2 domains. Association with endothelial cell proliferation

Vascular endothelial cell growth factor (VEGF), an endothelial cell-specific mitogen that plays an important role in angiogenesis, promotes the tyrosine phosphorylation of at least 11 proteins in bovine aortic endothelial cells (BAEC). Proteins immunoprecipitated from lysates of control- and VEGF-stimulated BAEC with antisera to phospholipase C-gamma (PLC-gamma) were fractionated by SDS-polyacrylamide gel electrophoresis and transferred to Immobilon-P. Evaluation of the Western blots with antisera to phosphotyrosine demonstrated that PLC-gamma and two proteins (100 and 85 kDa) that associate with PLC-gamma were phosphorylated in response to VEGF. By using antisera specific to other mediators of signal transduction that contain SH2 domains for immunoprecipitation, it was demonstrated that VEGF promotes phosphorylation of phosphatidylinositol 3-kinase, Ras GTPase activating protein (GAP), and the oncogenic adaptor protein NcK. Proteins of M(r) consistent with the VEGF receptors Flt-1 and Flk-1/KDR were also tyrosine phosphorylated in stimulated cells. Tyrosine-phosphorylated Nck, PLC-gamma, and two GAP-associated proteins, p190 and p62, were in GAP immunoprecipitates of VEGF-stimulated BAEC, and tyrosine-phosphorylated NcK was in phosphatidylinositol 3-kinase immunoprecipitates. These observations suggest that VEGF promotes formation of multimeric aggregates of VEGF receptors with proteins that contain SH2 domains and activate various signaling pathways. VEGF-promoted proliferation of endothelial cells and tyrosine phosphorylation of SH2 domain containing signaling molecules were inhibited by the tyrosine kinase inhibitor genistein.

Interaction of TPA and ultraviolet B radiation in regulation of ODC gene expression in rat keratinocytes

Ultraviolet B radiation (UVB) and phorbol esters are known to promote tumor formation in skin; however, the interaction between UVB and phorbol esters in the regulation of gene expression remains incompletely understood. To define the interaction of UVB and phorbol esters in the control of keratinocyte gene expression, we have studied the effects of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) and UVB on the regulation of ornithine decarboxylase (ODC) gene expression in a rat keratinocyte cell line. Both UVB and TPA alone increased ODC activity and induced the expression of the ODC gene. The combination of UVB and TPA produced a further increment in ODC gene expression at 12 h, but UVB markedly attenuated the TPA induction of ODC mRNA transcripts at 3 h. Protein synthesis inhibition with cycloheximide also induced ODC mRNA transcripts, but did not eliminate the further induction of ODC gene expression by UVB or TPA. No changes in actin gene expression following exposure to TPA/UVB were detected in the same experiments. UVB and TPA alone or in combination had no effect on the transcriptional activity of an ODC-chloramphenicol acetyltransferase fusion gene in transfected rat keratinocytes. The results of these studies suggest a complex posttranscriptional interaction of phorbol esters and UVB in the control of keratinocyte gene expression.

Ultraviolet B radiation induction of ornithine decarboxylase gene expression in mouse epidermis

The cellular effects of u.v. radiation have been studied by using a hairless-mouse model in vivo. U.v. B radiation (u.v.B) induced the activity of the enzyme ornithine decarboxylase (ODC) in mouse epidermis. Maximal induction was noted after radiation with 90 mJ/cm2, and increased ODC activity was first detected 2 h after u.v.B exposure. U.v.B. also induced the expression of the ODC gene in a time- and dose-dependent manner, but did not induce the levels of actin mRNA transcripts. Cycloheximide treatment did not alter basal levels of ODC mRNA transcripts and had no effect on the u.v.B induction of ODC-gene expression. The results of these experiments demonstrate that u.v.B radiation induces both the expression of the ODC gene and the activity of the enzyme, and provides a useful 'in vivo' paradigm for the analysis of the molecular effects of u.v.B radiation.