Zoonoses and potential zoonoses transmitted by bats

PURPOSE: The purpose of this study was to develop an analytical method for the quantitative determination of the extent of neutralization of the carboxylic acid function in Carbopol 974P NF using Diffuse Reflectance Fourier Transform Infrared Spectroscopy (DRIFT) with Kubelka-Munk function analysis. METHODS: Carbopol 974P NF is a high molecular weight, chemically crosslinked polymer of acrylic acid, that has the C=O stretching band of the unionized carboxylic acid function at 1695 cm(-1). The quantitative determination of the extent of neutralization of the carboxylic acid function in Carbopol 974P NF is based upon the asymmetrical C=O stretching of the carboxylate anion at 1570 cm(-1) measured by DRIFT spectroscopy. RESULTS: To overcome spectral differences arising from sample preparation (powders, granules and tablets) and in an effort to increase the precision of the analytical method, the following approaches were used: (1) an internal standard, (2) first derivative of the spectrum to eliminate the effect of baseline drift and (3) the ratio of the first derivative of the C=O stretch of the carboxylate anion peak (1570 cm(-1)) in the neutralized Carbopol 974P NF to that of the peak of the internal standard (866 cm(-1)). The above data treatment techniques proved to be superior to the usual methods of peak height or peak area. The calibration curve of the ratio of the first derivative (1570 cm(-1)/866 cm(-1)) was a linear function of the mass of sodium carboxylate over the range from 0.0% to 100.0% neutralization of the carboxylic acid function in Carbopol 974P NF (Fig. 1a). No particle size or sample preparation effects were noted within the experimental error. CONCLUSIONS: DRIFT spectroscopy using the Kubelka-Munk function is a powerful tool for the routine determination of the extent of neutralization of the carboxylic acid function in Carbopol 974P NF in complex pharmaceutical formulations.     

The HIV-inactivating protein, cyanovirin-N, does not block gp120-mediated virus-to-cell binding

Concentrations of the potent, HIV(human immunodeficiency virus) inactivating protein, cyanovirin-N (CV-N), which completely inhibit HIV-1 infectivity, do not block the binding of soluble CD4-receptor (sCD4) to HIV-1 lysates nor the attachment of intact HIV-1 virions to several target T-cell lines. Furthermore, in contrast to the known disassociative effects of sCD4 on viral envelope glycoproteins, treatment of HIVRF with high concentrations of CV-N results in complete viral inactivation but without apparent shedding of gp120 or other ultrastructural changes. These results are consistent with the view that the virucidal effects of CV-N result from interference with step(s) in the fusion process subsequent to the initial binding of the virus to target cells.     

Analysis of autoantibody epitopes on steroid 21-hydroxylase using a panel of monoclonal antibodies

A panel of five mouse monoclonal antibodies (MAbs) to human recombinant steroid 21-hydroxylase (21-OH) were produced, characterized, and used to study the interaction of 21-OH autoantibodies (AAbs) with different epitopes on human 21-OH. AAbs in patients with isolated autoimmune Addison's disease, autoimmune polyglandular syndromes types I and II, and 21-OH antibody-positive patients without overt Addison's disease (25 patients in total) were studied. Four MAbs were IgG1 subclass, one was IgG2a, and all had kappa light chains. The affinities of four of the antibodies were in the range 2.0 x 10(8) M(-1) to 7.0 x 10(8) M(-1), and the affinity of the other was 2.3 x 10(7) M(-1) 21-OH MAbs did not cross-react with 17alpha-hydroxylase (17alpha-OH)) or P450 side chain cleavage enzyme. Studies using a series of 21-OH fragments allowed the identification of short stretches of amino acids (AA) that were involved in forming the MAb binding sites. AA 391-405, defined as epitope region (ER) 1, were found to be important for binding of M21-OH1 and M21-OH2, AA 406-411 (ER2) were important for M21-OH3 and M21-OH4 binding, and AA 335-339 (ER3) for M21-OH5 binding. In addition, MAb Fab or F(ab')2 fragments were used to study 21-OH AAb epitopes in competition experiments. These investigations demonstrated that 21-OH AAbs recognize similar epitopes to the MAbs, with ER2 and ER3 being part of two distinct major epitopes, and ER 1 being part of a minor epitope. Mixtures of M21-OH antibody Fab or F(ab')2 fragments caused almost complete inhibition (80%-95%) of AAb binding in 24 out of 25 sera, and in the case of the remaining serum, the effect was marked but incomplete (67% inhibition). There were no major differences between the binding characteristics of AAbs from patients with different forms of autoimmune adrenal disease. All five 21-OH MAbs reacted with human adrenal tissue in an immunofluorescence test, but only M21-OH1 and M21-OH2 reacted with bovine adrenal tissue in these experiments. None of the MAbs reacted with human ovarian tissue in an immunofluorescence test. Overall, these studies indicate that 21-OH AAbs bind to at least three different epitopes in the C-terminal part of 21-OH, and two of these epitopes appear to be human 21-OH specific.     

Impact on human health of Salmonella spp. on pork in The Netherlands and the anticipated effects of some currently proposed control strategies

Cell-cell and cell-extracellular matrix interactions are fundamental processes involved in cell migration and tissue remodeling. Both the cyclic regeneration of the human endometrium during the menstrual cycle as well as the process of embryo implantation involve such dynamic interactions. It has become quite clear that integrin adhesion molecules expressed on the surface of cells play critical roles in the transmission of signals from the extracellular milieu to the cells. It is these signals that presumably regulate the behavior of these cells during major morphogenetic processes. In recent years, work in human endometrium and trophoblasts has uncovered both the regulated and constitutive expression of integrin subunits and their extracellular matrix ligands in these tissues. In addition, attempts have been made to correlate pathological states related to either infertility or abnormal pregnancy to the aberrant expression of several of these integrins. The purpose of the present review is to describe briefly our present state of knowledge of the expression of integrins in human endometrium and trophoblasts and provide the reader with the necessary background needed to understand, at the cellular and molecular levels, processes in reproduction such as embryo implantation.     

The role of dermabrasion and chemical peels in the treatment of patients with xeroderma pigmentosum

We describe our experience with two patients with xeroderma pigmentosum who underwent periodic trichloroacetic acid chemical peels. One also received a full-face dermabrasion. The effect of chemical peeling was more transient than dermabrasion but was associated with less morbidity. Both chemical peeling and dermabrasion provided a prophylactic effect against the development of skin malignancies; the latter had a more pronounced effect.     

Sequences within the amino terminus of ApoB100 mediate its noncovalent association with apo(a)

Although sequences within the C terminus of apolipoprotein B (apoB) have been implicated in the formation of covalent lipoprotein(a) [Lp(a)] particles, sequences in apoB that mediate initial noncovalent interaction with apo(a) remain to be characterized. To address this question, we have used an affinity chromatography method in which 2 recombinant forms of apo(a) [r-apo(a); either a 17-kringle form (17K) or a derivative containing apo(a) kringle IV types 5-8] have been immobilized onto Sepharose beads. Conditioned media from rat hepatoma (McA-RH7777) cell lines stably expressing various carboxyl-terminally truncated forms of human apoB (ranging from full-length apoB to apoB15) were applied to the r-apo(a) affinity columns; the columns were subsequently washed and eluted with epsilon-aminocaproic acid (epsilon-ACA). Specific binding was quantified by Western blot analysis of column fractions. Of the apoB truncations examined, apoB94, apoB42, apoB37, and apoB29 exhibited complete specific binding to 17K r-apo(a). Only approximately 50% binding was observed for apoB18, whereas essentially no detectable binding was observed with apoB15. In all cases, similar results were obtained when the r-apo(a) kringle IV types 5-8-Sepharose column was used. Additionally, substitution of proline for epsilon-ACA as the eluent resulted in similar column profiles with either r-apo(a) affinity column. We also demonstrated that apoB48 present in chylomicrons bound completely to the 17K column in an epsilon-ACA-dependent manner. Taken together, these results represent the first demonstration that N-terminal sequences in apoB between amino acid residues 680 (apoB15) and 781 (apoB18) are essential for noncovalent association with apo(a) and that these sequences interact with domain(s) present within apo(a) kringle IV types 5-8.     

Methodology of serial ECG classification using an adaptation of the NOVACODE for Q wave myocardial infarction in the Bypass Angioplasty Revascularization Investigation (BARI)

Serial electrocardiographic (ECG) changes are a critical component of the diagnostic algorithm for classification of myocardial ischemic events in large-scale clinical trials. This study describes a computerized serial ECG classification program developed at the St. Louis University Core ECG Laboratory for use in the Bypass Angioplasty Revascularization Investigation (BARI) trial, in which patients with multivessel coronary artery disease were randomized to receive either coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. The St. Louis University program detects and codes serial changes in Q, ST, and T wave items according to Minnesota code (MC) criteria using a modified NOVACODE hierarchical classification system. Measurements using a seven-power calibrated coding loupe are used to generate the MC from a customized software program. Significant minor or major changes are detected by the serial comparison program and referred to a physician coder for verification. Serial comparison coding rules are used to adjust for weaknesses in the standard MC classification system resulting from instability at decision boundaries. Of 4,244 BARI randomized and registry study participants with follow-up ECGs received at the Core ECG Laboratory as of March 1995, a grade 2 MC Q wave progression was noted in 568 participants (13.4%) using MC criteria alone, as compared with 367 (8.6%) after the St. Louis University coding rules were applied. The incidence of grade 1 MC Q wave progressions was 16.4% (697/4,244) versus 6.1% (259/4,244) when the St. Louis University program was applied. Intraobserver variability for grade 2 Q wave progression codes determined from a sample of 812 serial.     

Three-dimensional quantitative structure-activity relationship study of nonsteroidal estrogen receptor ligands using the comparative molecular field analysis/cross-validated r2-guided region selection approach

A newly developed comparative molecular field analysis (CoMFA) technique, the cross-validated r2-guided region selection (CoMFA/q2-GRS) method, has been used to build a quantitative structure-activity relationship (3D-QSAR) for nonsteroidal estrogen receptor (ER) ligands. Ligands included in this study belong to a series of diethylstilbestrol (DES) and indenestrol analogues whose affinities for the mouse ER (mER) have been determined in our laboratory. The final model utilized 30 compounds and yielded a q2GRS (cross-validated r2, guided region selection) of 0.796, as compared to a q2 of 0.720 for conventional CoMFA, with a standard error of prediction of 0.594 at 3 principal components. This model was used to visualize steric and electrostatic features of the ligands that correspond with ER binding affinity. Results obtained from the CoMFA steric and electrostatic plots of this model have also been compared to information from the ER binding affinities of substituted estradiol analogues. This is in an effort to determine structural features of compounds in the CoMFA analysis that may correspond to those of the estradiol analogues and to further clarify the mode of binding of nonsteroidal ER ligands.     

Clinimetrics of postural instability in Parkinson's disease

Judgement of the ability to recover balance after a sudden shoulder pull is used as a clinical measure of postural instability in Parkinson's disease. To further evaluate its merits, we compared this 'retropulsion test' with dynamic posturography in 23 Parkinson patients. Dynamic posturography involved 20 serial 'toe-up' support surface rotations, which induced backward body sway. We found a moderate correlation (Spearman's p = 0.54; P < 0.05) between the retropulsion test and body sway after platform rotations during the 'off' phase, but no correlation during the 'on' phase (Spearman's p = 0.43; P = 0.11). These results cast doubt on the use of the retropulsion test as a measure of postural instability in Parkinson's disease.