Nuclear cathepsin B-like protease cleaves transcription factor YY1 in differentiated cells.

Differentiation of pluripotent cells into differentiated cell types involves changes in many aspects of cellular biochemistry. Many of these changes result in alterations of gene expression, which may occur by changing the activity of transcription factors. The cell line NTERA-2 (NT2) can be differentiated into various cell types by incubation with retinoic acid. The differentiated cell type is also permissive for infection with the human herpesvirus cytomegalovirus (CMV). The transcription factor YY1 has been shown to regulate the immediate-early promoter of CMV in a differentiation specific manner by binding to one site at -958 to -950 and to at least two sites in the enhancer. It is demonstrated here that there is a second YY1 site in the modulator between -995 and -987. Levels of YY1 DNA binding activity and protein decrease in NT2 cells as they are differentiated with retinoic acid. This decrease in protein is due to the degradation of YY1 by a cathepsin B-like activity found in nuclear extracts. The cleavage products of YY1 include the intact C-terminal half of the protein, which contains the zinc fingers and the DNA binding activity. This suggests a mechanism that allows expression of the CMV immediate-early promoter in differentiated cells.

In situ detection of human cytomegalovirus immediate-early gene transcripts within cardiac myocytes of patients with HIV-associated cardiomyopathy.

OBJECTIVE: Recent clinical and echocardiographic studies have identified dilated cardiomyopathy in 10-20% of HIV-infected adults. The purpose of this study was to determine the role of cardiotropic cytomegalovirus (CMV) infection in the development of HIV-associated cardiomyopathy. DESIGN: We generated sense and antisense digoxigenin-labeled riboprobes derived from the CMV immediate-early (IE) and delayed-early (DE) genes and applied them retrospectively to endomyocardial biopsy samples and control autopsy cardiac samples from HIV-infected patients. SETTING: Tertiary care, referral hospital. PATIENTS: Twelve consecutive HIV-infected patients with global left ventricular hypokinesis demonstrated on two-dimensional echocardiography; eight randomly selected control autopsy cardiac samples from HIV-infected patients without cardiac disease during life. MEASUREMENTS AND MAIN RESULTS: Of the 12 endomyocardial biopsy specimens, six (50%) were found to have specific myocyte nuclear and perinuclear hybridization for transcripts of the CMV IE gene, consistent with non-permissive or latent infection. Similar patterns were not found in any of the eight autopsy control samples. All six patients presented with unexplained congestive heart failure and had CD4 counts less than 100 x 10(6)/l; all six biopsy samples had immunohistochemical evidence of increased myocardial major histocompatibility complex (MHC) class I expression, a finding typical of non-HIV myocarditis. None of the endomyocardial biopsy samples had characteristic CMV inclusions and no specific hybridization was noted with the DE gene riboprobe, suggesting that no active viral DNA replication was present. Only two of the six patients with myocyte hybridization with the IE riboprobe had clinical evidence of solid organ infection with CMV at the time of cardiovascular presentation. CONCLUSIONS: This study is the first to demonstrate the expression of the IE gene of CMV within myocytes from HIV-infected patients with cardiomyopathy, suggesting a non-permissive infection of myocytes without classical intranuclear inclusions. Myocyte infection may be necessary to trigger cellular and humoral-mediated cardiac injury and may be best identified using in situ hybridization techniques.

NMR determination of trimethoprim and sulfamethoxazole in tablets and powders.

An NMR spectroscopic method for the determination of mixtures of trimethoprim and sulfamethoxazole is described. Spectra are determined in dimethylsulfoxide-d6, containing 1,4-dinitrobenzene as an internal standard. Both synthetic mixtures and commercial formulations were assayed, and the results were compared to those obtained using the BP procedure.

NMR determination of isosorbide dinitrate and beta-adrenergic blocking agents in tablets.

An NMR spectroscopic method for the determination of isosorbide dinitrate, alone or together with alprenolol or propranolol, is described. Spectra are determined in dimethyl sulfoxide-d6 containing maleic acid or 1,4-dinitrobenzene as internal standards. Both synthetic mixtures and commercial formulations were assayed, and the results were compared using compendial procedures.

Development and validation of a reversed-phase liquid chromatographic method for analysis of estradiol valerate and medroxyprogesterone acetate in a tablet formulation.

A simple and accurate liquid chromatographic method was developed for estimation of estradiol valerate and medroxyprogesterone acetate in pharmaceuticals. Drugs were chromatographed on a reverse phase C18 column, using a mixture (30:70) of ammonium nitrate buffer and acetonitrile and eluants monitored at a wavelength of 280 nm. Solution concentrations were measured on a weight basis to avoid the use of an internal standard. The method was statistically validated for its linearity, accuracy, precision and selectivity. Due to its simplicity and accuracy, the authors believe that the method may be used for routine quality control analysis. It does not require any specific sample preparation except the use of a column guard before the analytical column and suitable prefilter attached to the syringe prior to injection.

HPLC analysis of 5H-benzo[a]carbazole with antifungal activity.

A sensitive and simple high-performance liquid chromatographic (HPLC) method for the assay of 6,11-dihydro-2-methoxy-5H-benzo[a]carbazole (1) and 6,11-dihydro-2-methoxy-11-[2-(1-piperidinyl)]ethyl-5H-benzo[a]carbazole (2) was developed. The procedure is based on the use of the reversed-phase high-performance liquid chromatographic (RP-HPLC) method with UV detector. Each analysis required no longer than 11 min. A linear relationship between the concentration of both the drugs and the UV absorbance at 254 nm was obtained. This linearity was maintained over the concentration ranged from 5 to 80 microg/ml. The detection limits were found to be 1.6 and 0.7 ng for compounds 1 and 2. The quantitation limits were found to be 5.3 and 2.5 ng for compounds 1 and 2, respectively. For recovery studies, several determinations were carried out. Recovery values ranged from 98 to 102.1% for compound 1 and from 98.4 to 101.6% for compound 2. Method precision was also evaluated and RSD% found was less than 2%. This method was applied without any interference from degradation products.

Antimicrobial activity of 5,6-dihydrobenzo-[a]-carbazoles. Part II.

A new series of twenty-two 5,6-dihydrobenzo[a]carbazoles was synthesized, some showing good antibacterial activity. The presence and position of substituents seems to be critical for such activity.

Antimicrobial activity of 5,6-dihydrobenzo-[a]-carbazoles.

A new series of 5,6-dihydrobenzo[a]carbazoles was synthesized, some showing good antibacterial activity. The presence of a dialkylamino ethyl chain on the 2-, 3- or 4-O-substituent seems to be critical for such activity.

Synthesis of disubstituted tetrahydrocarbazoles with potential antidepressive activity.

A new series of disubstituted tetrahydrocarbazoles were synthesized. They are tested for antidepressive activity by the Porsolt's forced swimming test (one of the acute stress methods) and by the prevention of reserpine induced hypothermia and ptosis in mice. 3-Morpholino-1-[N-(6-methoxy-1,2,3,4- tetrahydrocarbozolyl)2-propanol, fumarate (XI) was demonstrated to be the most promising compound of this series. Besides, this series did not present the most common adverse effects of the conventional tricyclic-antidepressants (loss of locomotor coordination, ataxia and anticholinergic activity).

Antitumoral activity of trisubstituted dihydrobenzo(a)carbazoles. Part III.

Two recently synthesized, trisubstituted dihydrobenzo(a)carbazoles were investigated regarding their anti-HIV and antitumoral activity. The compounds showed some activity against melanoma, renal cancer and breast cancer cell lines.

Bioavailability study of paracetamol tablets in saliva and urine.

A bioavailability study of two lots of paracetamol tablets was carried out in 5 healthy volunteers, using a crossover aleatory design, and drug monitoring in urine and saliva by high performance liquid chromatography (HPLC). Results were correlated with those obtained in an in vitro dissolution study. Statistical evaluation of bioavailability parameters indicates that the two formulations may be considered bioequivalent, in spite of differences found during early stages of the absorption process, which were preventable according to an in vitro dissolution study.

Stability study of lipoic acid in the presence of vitamins A and E in o/w emulsions for cosmetic application.

The effectiveness of any cosmetic product containing a functional ingredient is determined by the skin delivery of the active molecule, which is influenced by the type of carrier and the molecule itself. Furthermore, the functional ingredient should be stable in the formulation. The purpose of this paper is to study the stability of lipoic acid in the presence of vitamins A (as palmitate) and E (as acetate) in semisolids for cosmetic use. The systems formulated were studied in regard to their aspect, pH, stability under centrifugation, and rheological behavior. The chemical analyses of lipoic acid and vitamins A and E were carried out by HPLC after studying the specificity of the method employed in each case. The quantitation of the active principles was performed by HPLC with C18 (5 microm) columns. The mobile phase was methanol for the vitamins, with spectrophotometric detection at 325 nm for vitamin A and 230 nm for vitamin E. The mobile phase for lipoic acid was methanol:water (80:20) and phosphoric acid at pH 3.0, with spectrophotometric detection at 332 nm. All systems were stable to centrifugation, and no significant modification of rheological behavior was observed in relation to the base emulsion used as control. The chemical studies performed indicated that although lipoic acid is not very stable in these formulations, the presence of vitamin A favors its chemical stability.

Synthetic trypanocides: growth-inhibiting properties of new 1,2,3,4-tetrahydrocarbazoles on Trypanosoma cruzi.

Several new 1,2,3,4-tetrahydrocarbazole, 5,6-dihydrobenzo(alpha) carbazole, 3-methylindole and substituted benzimidazolyl compounds were synthesized and assayed for their action on growth of Trypanosoma cruzi, cultured in Warren's liquid medium. 6-chloro and 6,8-dichloro-N-(1-ethyl-N-diethylamino)-1,2,3,4-tetrahydrocarbazole++ fumarate resulted the more active in inhibiting growth of the parasite. The new compounds were apparently more effective than those prepared previously by Poliakoff et al. (5).

Effect of manufacturing technology on the dissolution of ampicillin tablets.

The effect of the manufacturing technology on the dissolution of ampicillin tablets have been analyzed. Several kinetic parameters were then calculated. The dissolution rate of ampicillin increases in tablets prepared by direct compression or dry granulation, with microcrystalline cellulose and colloidal silicon dioxide. Studies of in vitro bioequivalence of the pharmaceutical products available in the Argentine market were performed. We concluded that not all commercial products are equivalent.

Urinary JCV-DNA testing during natalizumab treatment may increase accuracy of PML risk stratification.

The risk of progressive multifocal leukoencephalopathy (PML) in patients treated with natalizumab for multiple sclerosis (MS) is a serious concern. The presence of anti-JC virus antibodies is a risk factor for PML development, but 2.5 % of the patients result falsely-negative, while the prognostic relevance of testing JCV-DNA in biological fluids of treated patients is debated. Aim of this work was to evaluate the utility of testing JCV-DNA, together with anti-JCV antibodies, in biological samples of treated patients as a tool for PML risk stratification. 126 subjects from 5 MS Centers in Italy were included in the study. We performed a cross-sectional study in 63 patients testing JCV-DNA in blood, peripheral blood cells and urine. We longitudinally assessed the presence of JCV-DNA in a cohort of 33 subjects, one of which developed PML. We could test retrospectively serum samples from another PML case occurred during natalizumab therapy. Anti-JCV antibodies and urinary JCV-DNA were both tested in 73 patients. No changes in JCV-DNA status occurred during natalizumab treatment. The subject who developed PML in the longitudinal cohort had detectable JCV-DNA in urine at all time-points while serum or blood from both PML patients were always negative before the onset of disease and, in one case, after. Four subjects with JCV-DNA in urine and undetectable anti-JCV antibodies were retested for anti-JCV antibodies and three out of four resulted positive. In conclusion, testing JCV-DNA in urine is complementary to testing anti-JCV antibodies in identifying patients at risk of PML.

The IE2 gene products of human cytomegalovirus specifically down-regulate expression from the major immediate-early promoter through a target sequence located near the cap site.

The 82-kDa IE2 protein of human cytomegalovirus (HCMV) acts as both a powerful nonspecific trans activator of heterologous promoters and a negative autoregulator of HCMV immediate-early gene expression in transient assays. We show here that the highly specific down-regulation effect occurs in permissive diploid human fibroblast cells as well as in nonpermissive Vero cells and that the target sequences are conserved within the major immediate-early promoters of both HCMV and simian cytomegalovirus. The response sequences were localized between -67 and +30 in the simian cytomegalovirus IE94 promoter and upstream of position +9 in the HCMV IE68 promoter. Deletion of sequences downstream of -14 in a target IE68-CAT gene abolished the negative phenotype and resulted in a reporter gene that was stimulated instead of inhibited by cotransfection with IE2 effector DNA. Insertion of an oligonucleotide containing sequences from between -17 and +9 into the IE68-CAT deletion construction restored autoregulation in either orientation. Furthermore, this same oligonucleotide transferred the full down-regulation phenotype when inserted at +10 into the nonresponsive IE175 promoter from herpes simplex virus. Therefore, a specific response signal that acts at the DNA level must lie within these boundaries. Additional analysis with inserted oligonucleotides containing deletions or point mutations revealed that essential components of the signal lie between positions -12 and +5. Therefore, negative autoregulation by HCMV IE2 in DNA cotransfection systems resembles that for simian virus 40 large T antigen and herpes simplex virus IE175 by acting through a signal located near the cap site, but the target sequence itself bears no resemblance to those utilized in these other viral systems.

Conformational analysis of optically active phenylethylamines and phenylimidazolines.

Conformational and structural features of phenethylamine and phenylimidazoline derivatives with alpha-adrenergic activity have been studied by MNDO and PCILO methods. From the calculated conformational energy maps, we conclude that phenethylamines exhibit an extended conformation, while the phenylimidazolines adopt a position intermediate between that of corresponding extended and folded conformations. We conclude that the phenethylamines interact with classical Easson-Stedman sites, while the phenylimidazolines interact with a different site. Both phenethylamines and phenylimidazolines show similar requirements for a cationic recognition site.