Anesthesia breathing circuits protected by the DAR Barrierbac S breathing filter have a low bacterial contamination rate

PURPOSE

In order to reuse the same anesthesia breathing circuit for more than one patient, it has been proposed to add a breathing filter between the Y-piece and the artificial airway. The purpose of this study was to evaluate the in vivo bacterial filtration efficacy of an anesthesia filter in a usual clinical anesthesia setting.

METHODS

A sterile DAR Barrierbac S breathing filter was inserted at the Y-piece of a sterile single-use anesthesia breathing circuit before induction of general anesthesia. At the end of anesthesia, the breathing circuit connector of the filter and of the endotracheal tube connector were cultured separately on growth media (chocolate and blood agar). These were incubated for 48 hr and bacterial identification was conducted using standard methods.

RESULTS

Bacterial cultures were negative on both sides of the filter membrane of 1842 of the 2001 filters studied. Cultures were positive on the patient side of 104 filters. In two of those, the same bacteria were found on both the circuit side and the patient side of the filter. Therefore these data indicate a clinical effectiveness of 99.9% (confidence interval, CI 95%, 99.6-99.998%), and an in vivo filtration efficacy of 98.08% (CI 95%, 92.54-99.67%).

CONCLUSION

Using the upper limit of the CI, it can be assumed that the practice of using a sterile DAR Barrierbac S breathing filter for every patient while reusing the anesthesia breathing circuit would result in a cross contamination rate of the breathing circuit lower than once every 250 cases.

Biological monitoring of environmental exposure to polycyclic aromatic hydrocarbons in subjects living in the vicinity of a creosote impregnation plant

OBJECTIVE

This study was undertaken to evaluate the environmental exposure to polycyclic aromatic hydrocarbons (PAHs) in nonsmoking adult subjects living in the vicinity of a creosote impregnation plant in Delson, Canada. Urinary metabolites of naphthalene, alpha- and beta-naphthol, and pyrene metabolite 1-hydroxypyrene (1-OHP), were used as biomarkers of exposure.

METHODS

Morning and evening urine samples were collected in mid-August from 30 exposed individuals living at a distance of 50-360 m downwind of the plant and from a control group in the adjoining municipality residing at a distance of 1.9-2.7 km upwind of the plant. Metabolites were measured by gas chromatography/ mass spectrometry.

RESULTS

Excretion values of alpha- and beta-naphthol were significantly higher in the exposed group than in controls (P < 0.04), after accounting for possible confounding variables by multivariate analyses. The respective geometric mean concentrations (5th and 95th percentiles) of alpha-naphthol for the exposed and nonexposed groups were 2.04 (0.55-6.00) and 1.37 (0.39-7.02) micromol/mol creatinine for evening samples, and 2.49 (0.77-8.43) and 1.17 (0.37-6.88) micromol/mol creatinine for morning samples. Corresponding values for beta-naphthol were 1.78 (0.82-3.67) and 1.36 (0.63-5.07) micromol/mol creatinine for evening samples, and 1.94 (1.03-4.96) and 1.08 (0.49-5.05) micromol/mol creatinine for morning samples. On the other hand, no significant difference in 1-OHP excretion was observed between the exposed and the control group (P>0.5). The respective geometric mean concentrations (5th and 95th percentiles) of 1-OHP for these groups were 0.05 (0.01-0.17) and 0.06 (0.01-0.48) micromol/mol creatinine for evening samples, and 0.05 (0.02-0.12) and 0.05 (0.01-0.42) micromol/mol creatinine for morning samples.

CONCLUSIONS

The measurement of alpha- and beta-naphthol urinary concentrations appears to be an approach sufficiently sensitive to reveal differences in low exposure levels of volatile PAHs due to creosote impregnation plant emissions. However, uptake of pyrene due to the plant was too small to contribute significantly to 1-OHP excretion.

Evolution and transmission of stable CTL escape mutations in HIV infection

Increasing evidence indicates that potent anti-HIV-1 activity is mediated by cytotoxic T lymphocytes (CTLs); however, the effects of this immune pressure on viral transmission and evolution have not been determined. Here we investigate mother-child transmission in the setting of human leukocyte antigen (HLA)-B27 expression, selected for analysis because it is associated with prolonged immune containment in adult infection. In adults, mutations in a dominant and highly conserved B27-restricted Gag CTL epitope lead to loss of recognition and disease progression. In mothers expressing HLA-B27 who transmit HIV-1 perinatally, we document transmission of viruses encoding CTL escape variants in this dominant Gag epitope that no longer bind to B27. Their infected infants target an otherwise subdominant B27-restricted epitope and fail to contain HIV replication. These CTL escape variants remain stable without reversion in the absence of the evolutionary pressure that originally selected the mutation. These data suggest that CTL escape mutations in epitopes associated with suppression of viraemia will accumulate as the epidemic progresses, and therefore have important implications for vaccine design.

Anti-inflammatory activity of clarithromycin in adults with chronically inflamed sinus mucosa

In a phase IV, open-label study, 25 patients with clinically stable chronic sinusitis and persistent maxillary sinus inflammation were treated for 14 days with clarithromycin 500 mg twice daily. Biopsy specimens of the maxillary sinus mucosa were obtained pretreatment and evaluated for macrophages (CD68), eosinophils (MBP), elastase, interleukin-6 (IL-6), IL-8, tumor necrosis factor-alpha (TNF-alpha), and activity of eosinophils (EG2), as well as edema score. Clinical signs and symptoms were assessed pretreatment, at the end of treatment, and 1 and 2 weeks later. Statistically significant reductions (P < or = .05) from pretreatment were observed for all markers of sinus mucosal inflammation, including CD68, EG2, elastase, IL-6, IL-8, TNF-alpha, and edema score, with a trend to decreased total eosinophil count. Improvement was observed for all clinical signs and symptoms of chronic sinusitis--sinus pain, sinus headache, nasal congestion, nasal discharge, and mucopurulent discharge--up to 14 days after the end of treatment. Cultures to evaluate persistent infection with Chlamydia pneumoniae showed negative results. Significant reductions in various markers of sinus mucosal inflammation support the role of clarithromycin in modulating immunologic responses. Improvement of clinical signs and symptoms in patients with chronic inflammatory sinusitis not meeting criteria for known or presumed bacterial infection was also noted up to 2 weeks after completion of a 14-day course of clarithromycin.

Low- and high-density lipoprotein metabolism in HepG2 cells expressing various levels of apolipoprotein E

To determine the importance of hepatic apolipoprotein (apo) E in lipoprotein metabolism, HepG2 cells were transfected with a constitutive expression vector (pRc/CMV) containing either the complete or the first 474 base pairs of the human apoE cDNA inserted in an antisense orientation, for apoE gene inactivation, or the full-length human apoE cDNA inserted in a sense orientation for overexpression of apoE. Stable transformants were obtained that expressed 15, 24, 226, and 287% the apoE level of control HepG2 cells. The metabolism of low-density lipoprotein (LDL) and high-density lipoprotein-3 (HDL(3)), two lipoprotein classes following both holoparticle and cholesteryl esters (CE)-selective uptake pathways, was compared between all these cells. LDL-protein degradation, an indicator of the holoparticle uptake, was greater in low apoE expressing cells than in control or high expressing cells, while HDL(3)-protein degradation paralleled the apoE levels of the cells (r(2) = 0.989). LDL- and HDL(3)-protein association was higher in low apoE expressing cells compared to control cells. In opposition, LDL- and HDL(3)-CE association was not different from control cells in low apoE expressing cells but rose in high apoE expressing cells. In consequence, the CE-selective uptake (CE/protein association ratio) was positively correlated with the level of apoE expression in all cells for both LDL (r(2) = 0.977) and HDL(3) (r(2) = 0.998). We also show that, although in normal and low apoE expressor cells, 92% of LDL- and 80% HDL(3)-CE hydrolysis is sensitive to chloroquine suggesting a pathway linked to lysosomes for both lipoproteins, cells overexpressing apoE lost 60% of chloroquine-sensitive HDL(3)-CE hydrolysis without affecting that of LDL-CE. Thus, the level of apoE expression in HepG2 cells determines the fate of LDL and HDL(3).

[Biological monitoring of exposure to polycyclic aromatic hydrocarbons among people living nearby an aluminum smelter in the province of Québec]

BACKGROUND

The objective of the study is to estimate the exposure to pyrene, an indicator of polycyclic aromatic hydrocarbons (PAHs) in the general environment, by using the internal dose of 1-hydroxypyrene (1-OHP) among people living nearby an aluminium smelter in the Montérégie area, Province of Québec, Canada.

METHODS

This cross-sectional study was done in November and December 1998. Participants were randomly selected according to their environmental exposure to PAHs and were distributed according to three exposure levels (high, low, none). Altogether, 121 non smokers aged between 18 to 70 years were recruited for the study. Persons occupationally exposed to PAHs or using tar-based medications were excluded. Those with personal medical conditions that affect the metabolism of pyrene were also excluded. Urine samples were taken in the morning and analysed by gas chromatography and mass spectrometry (GC-MS) to determine the concentration of the metabolite, 1-OHP.

RESULTS

Among the exposed group (n=78), the geometric mean of urinary concentration of 1-OHP was 0.073 micromol/mol creatinine compared to 0.060 micromol/mol creatinine for the control group (n=40). The difference did not reach statistical significance (p=0.09). Geometric means among the three groups of exposure (high, low, none) were respectively 0.079, 0.067 and 0.060 micromol/mol creatinine (p=0.13). Accounting for personal risk factors, such as diet, passive smoke, use of wood heating and time spent at home during the three days prior to urine sampling, did not change previous results.

CONCLUSION

This study indicates that the environmental levels of PAH produced by this factory are low and do not contribute significantly to the body burden of PAH as measured by 1-OHP.

Synovial sarcoma in an Ayrshire heifer

An 8-month-old Ayrshire heifer had a rapidly growing mass in the axillary region of the left thoracic limb. The mass surrounded the distal humerus and entrapped nerves of the brachial plexus, causing an abnormal gait. Histologically, the mass was composed of clusters and cords of round to polygonal cells with scattered, spindle-shaped cells. The neoplastic cells stained positively for vimentin and cytokeratin. No staining was found with S-100 protein, kappa and lambda light chains, or T-cell markers by immunohistochemistry. On electron microscopic evaluation, the cytoplasm of the neoplastic cells contained few organelles, principally rough and smooth endoplasmic reticulum and mitochondria. This synovial sarcoma has histologic and ultrastructural features characteristic of the poorly differentiated subtype of synovial sarcoma in the human classification system.

An important proportion of genital samples submitted for Chlamydia trachomatis detection by PCR contain small amounts of cellular DNA as measured by beta-globin gene amplification

We assessed the quality of genital samples submitted for Chlamydia trachomatis detection by PCR by a second PCR assay for the presence of human beta-globin DNA. Endocervical and urethral samples were first tested by the COBAS AMPLICOR C. trachomatis assay (Roche Diagnostic Systems) with an internal control and were then amplified for the presence of beta-globin DNA with primers PC04 and GH20. Samples that contained inhibitors were retested after dilution 1:10. A total of 407 genital samples (311 endocervical swabs from 311 women and 96 urethral swabs from 95 men and 1 woman) collected over a 1-month period were evaluated. The internal control could not be amplified, despite dilution, from 3 of 23 samples that were retested after dilution because of inhibition, leaving 404 samples that could be analyzed by PCR. Eleven samples tested positive for C. trachomatis. Thirty (7.4%) of the 404 samples were negative for beta-globin. Twelve of the 23 undiluted samples that contained inhibitors tested positive for beta-globin DNA. Amplification of beta-globin DNA in samples submitted for C. trachomatis detection by the COBAS AMPLICOR C. trachomatis assay demonstrated that an important proportion of the samples did not contain cellular DNA. Assessment of the quality of the samples for PCR analysis by beta-globin amplification is feasible but cannot replace use of the internal control.

Interactions among combinations of two and three protease inhibitors against drug-susceptible and drug-resistant HIV-1 isolates

Protease inhibitors used in combination with reverse transcriptase inhibitors have demonstrated potent anti-HIV-1 activity in vitro as well as in vivo. We evaluated interactions among five protease inhibitors: indinavir (IDV), ritonavir (RTV), saquinavir (SQV), amprenavir (APV), and nelfinavir (NFV), when used in combinations of two and three drugs in vitro against several HIV-1 isolates, including those susceptible and resistant to various nucleoside and nonnucleoside reverse transcriptase inhibitors. Interactions ranged from synergy to slight antagonism depending on the viral isolates and the experimental conditions employed. Further clinical evaluation of protease inhibitor combinations is warranted.

Coping strategies and social support as mediators of consequences in child sexual abuse victims

OBJECTIVE

The main objective of this study was to evaluate the mediator role of coping strategies and social support on the adaptation of children following CSA. Empirical studies indicate that short-term consequences of child sexual abuse (CSA) are multiple and varied (Kendall-Tackett, Williams, & Finkelhor, 1993; Wolfe & Birt, 1995). While abuse-related characteristics were first studied to explain the variability of CSA outcome, more recently, the influence of other variables such as coping strategies and social support have been considered.

METHOD

Fifty sexually abused children aged between 7 and 12 participated in this study. The Child Behavior Checklist (Achenbach, 1991) and the Perceived Competence Scale for Children (Harter, 1985) were used to measure victims' adjustment. Coping strategies were evaluated by the Self-Report Coping Scale (Causey & Dubow, 1992) and the children completed the Perceived Social Support (Harter, 1985). A French version of the History of Victimization (Wolfe, Gentile, & Bourdeau, 1987) was used to gather abuse-related characteristics from medical records.

RESULTS

Results indicate that sexually abused children exhibit internalizing and externalizing behavior problems following CSA. Coping strategies and social support exert direct effects on victims' adjustment instead of the mediator influences originally expected. Among abuse-related variables, only the perpetrator's identity is directly related to internalizing symptoms.

CONCLUSIONS

The absence of mediational effects of coping and social support is discussed in light of the measures used and the cross-sectional nature of the study. Results highlight the importance of parental implication and the consideration of coping strategies in designing therapeutic interventions with this population.

Induction of prostaglandin G/H synthase-2 in a canine model of spontaneous prostatic adenocarcinoma

BACKGROUND

Prostate cancer is the most frequently occurring cancer in men in the United States, with an estimated 179 300 new cases in 1999. The induction of prostaglandin G/H synthase (PGHS), a key rate-limiting enzyme in prostaglandin biosynthesis, has been implicated in various cancers, most notably in colorectal cancers; however, the induction of PGHS expression in prostate cancer in vivo has not been reported for any species. The dog is the only nonhuman species that frequently develops spontaneous cancer of the prostate with increasing age, and the objective of this study was to determine whether PGHS isoenzymes were expressed in canine prostatic adenocarcinomas.

METHODS

Four normal canine prostatic tissues and 24 canine prostatic adenocarcinomas were studied by means of immunohistochemistry and immunoblot analysis, using polyclonal antibodies specific for each of the two PGHS isoenzymes, PGHS-1 and PGHS-2. All P values were obtained by use of two-sided Fisher's exact tests.

RESULTS

PGHS-1 immunostaining was localized to stromal fibroblasts and vascular endothelium in normal and cancerous prostates. PGHS-2 was not detected in normal prostates, but it was expressed by epithelial tumor cells in 18 (75%) of the 24 adenocarcinomas (P =.01). Immunoblot analysis confirmed the presence of PGHS-1 (69 000 molecular weight) in normal and cancerous tissues and the expression of PGHS-2 (72 000- to 74 000-molecular-weight doublet) only in prostatic adenocarcinomas.

CONCLUSION

To our knowledge, these results demonstrate for the first time that PGHS-2 is induced in the majority of canine spontaneous prostatic adenocarcinomas and suggest that its expression may be involved in prostate cancer.

Selective uptake of cholesteryl esters from various classes of lipoproteins by HepG2 cells

Selective uptake of cholesteryl esters (CE) from lipoproteins by cells has been extensively studied with high density lipoproteins (HDL). It is only recently that such a mechanism has been attributed to intermediate and low density lipoproteins (IDL and LDL). Here, we compare the association of proteins and CE from very low density lipoproteins (VLDL), IDL, LDL and HDL3 to HepG2 cells. These lipoproteins were either labelled in proteins with 125I or in CE with 3H-cholesteryl oleate. We show that, at any lipoprotein concentration, protein association to the cells is significantly smaller for IDL, LDL, and HDL3 than CE association, but not for VLDL. At a concentration of 20 microg lipoprotein/mL, these associations reveal CE-selective uptake in the order of 2-, 4-, and 11-fold for IDL, LDL, and HDL3, respectively. These studies reveal that LDL and HDL3 are good selective donors of CE to HepG2 cells, while IDL is a poor donor and VLDL is not a donor. A significant inverse correlation (r2 = 0.973) was found between the total lipid/protein ratios of the four classes of lipoproteins and the extent of CE-selective uptake by HepG2 cells. The fate of 3H-CE of the two best CE donors (LDL and HDL3) was followed in HepG2 cells after 3 h of incubation. Cells were shown to hydrolyze approximately 25% of the 3H-CE of both lipoproteins. However, when the cells were treated with 100 microM of chloroquine, a lysosomotropic agent, 85 and 40% of 3H-CE hydrolysis was lost for LDL and HDL3, respectively. The fate of LDL and HDL3-CE in HepG2 cells deficient in LDL-receptor was found to be the same, indicating that the portion of CE hydrolysis sensitive to chloroquine is not significantly linked to LDL-receptor activity. Thus, in HepG2 cells, the magnitude of CE-selective uptake is inversely correlated with the total lipid/protein ratios of the lipoproteins and CE-selective uptake from the two best CE donors (LDL and HDL3) appears to follow different pathways.

Low density lipoprotein-receptor plays a major role in the binding of very low density lipoproteins and their remnants on HepG2 cells

The binding to HepG2 cells of very low density lipoproteins (VLDL) and their remnants (IDL) was alternatively, in the past, attributed to the low density lipoprotein receptor (LDLr) or to an apoE-specific receptor. In order to resolve this issue, we have compared the binding of those lipoproteins labelled with iodine-125 to normal and LDLr deficient HepG2 cells. Those deficient cells were obtained by a constitutive antisense strategy and their LDLr level is 14% the level of normal HepG2 cells. By saturation curve analysis, we show that VLDL and IDL bind to high and low affinity sites on cells. The low affinity binding was eliminated by conducting the assay in presence of a 200-fold excess of HDL3 respective to the concentrations of 125I-labelled VLDL and IDL. For 125I-VLDL high affinity binding to normal HepG2 cells, we found a dissociation constant (Kd) of 21.2 +/- 3.7 micrograms prot./ml (S.E., N = 5) and a maximal binding capacity (Bmax) of 0.0312 +/- 0.0063 microgram prot./mg cell prot, while we have measured a Kd of 5.3 +/- 0.8 and a Bmax of 0.0081 +/- 0.0014 with LDLr deficient cells. This indicates that LDLr is responsible for 74% of VLDL binding to HepG2 cells and that the non-LDLr high affinity receptor has a higher affinity for VLDL than LDLr. A 53% loss of 125I-IDL binding capacity was measured with LDLr deficient cells compared with normal cells (Bmax: 0.028 +/- 0.005 versus 0.059 +/- 0.006), while no significant statistical difference was found between affinities. The study shows that the LDLr is almost the only contributor in VLDL binding, while it shares IDL binding capacity with another high affinity receptor. The physiological importance of LDLr is confirmed by an almost equivalent loss of IDL and VLDL degradation in LDLr deficient cells.

How effective are supplementary doses of opioids for dyspnea in terminally ill cancer patients? A randomized continuous sequential clinical trial

Supplementary doses of opioids are recommended to relieve dyspnea in terminally ill cancer patients. We conducted a randomized continuous sequential clinical trial to evaluate their efficacy. We recruited 33 terminally ill cancer patients from three palliative care centers, all of whom had persistent dyspnea after rest and treatment with oxygen. Patients formed 15 successive pairs matched on route of administration. Within each pair, the order of allocation was randomly assigned, one patient receiving 25%, the other 50% of his 4-hourly opioid dose. Five measurements of dyspnea intensity and respiratory frequency were made during 4 hours of follow-up. For each pair, a preference was attributed to the more effective regimen. The two regimens received an almost equal number of paired preferences (8 vs. 7). Overall, both mean dyspnea intensity and respiratory frequency decreased significantly relative to baseline. Dyspnea reduction was relatively greater in patients with initially low and moderate dyspnea intensity. In terminally ill cancer patients with persistent dyspnea, 25% of the equivalent 4-hourly dose of opioid may be sufficient to reduce both dyspnea intensity and tachypnea for 4 hours.

Uptake and fate of class B scavenger receptor ligands in HepG2 cells

Class B scavenger receptors (SR-Bs) interact with native, acetylated and oxidized low-density lipoprotein (LDL, AcLDL and OxLDL), high-density lipoprotein (HDL3) and maleylated BSA (M-BSA). The aim of this study was to analyze the catabolism of CD36- and LIMPII-analogous-1 (CLA-1), the human orthologue for the scavenger receptor class B type I (SR-BI), and CD36 ligands in HepG2 (human hepatoma) cells. Saturation binding experiments revealed moderate-affinity binding sites for all the SR-B ligands tested with dissociation constants ranging from 20 to 30 microg.mL-1. Competition binding studies at 4 degrees C showed that HDL and modified and native LDL share common binding site(s), as OxLDL competed for the binding of 125I-LDL and 125I-HDL3 and vice versa, and that only M-BSA and LDL may have distinct binding sites. Degradation/association ratios for SR-B ligands show that LDL is very efficiently degraded, while M-BSA and HDL3 are poorly degraded. The modified LDL degradation/association ratio is equivalent to 60% of the LDL degradation ratio, but is three times higher than that of HDL3. All lipoproteins were good cholesteryl ester (CE) donors to HepG2 cells, as a 3.6-4.7-fold CE-selective uptake ([3H]CE association/125I-protein association) was measured. M-BSA efficiently competed for the CE-selective uptake of LDL-, OxLDL-, AcLDL- and HDL3-CE. All other lipoproteins tested were also good competitors with some minor variations. Hydrolysis of [3H]CE-lipoproteins in the presence of chloroquine demonstrated that modified and native LDL-CE were mainly hydrolyzed in lysosomes, whereas HDL3-CE was hydrolyzed in both lysosomal and extralysosomal compartments. Inhibition of the selective uptake of CE from HDL and native modified LDL by SR-B ligands clearly suggests that CLA-1 and/or CD36 are involved at least partially in this process in HepG2 cells.

Improved CD4 lymphocyte outgrowth in response to effective antiretroviral therapy

CD4 lymphocyte regenerative capacity was evaluated by use of an ex vivo outgrowth assay in human immunodeficiency virus (HIV)-1-infected subjects enrolled in a clinical trial (Merck 039). CD4 lymphocytes were selectively expanded in vitro by T cell receptor triggering, which also induces HIV production from latently infected cells. CD4 cell expansion and lack of virus production in cultures correlated well with clinical responses and were best in those receiving an aggressive antiretroviral three-drug regimen. Twelve clinical responders receiving triple-drug therapy monitored for 60 weeks had both excellent ex vivo CD4 cell expansion and lack of HIV replication, often in the absence of added drug in culture. Breakthrough viruses recovered from drug-containing arms of the cultures showed phenotypic resistance to the drugs used in vivo. This CD4 lymphocyte outgrowth assay correlates well with clinical outcome in subjects receiving potent antiretroviral regimens and may predict the emergence of early drug resistance.

Ventricular ependymoma in a cat

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Antimicrobial susceptibility testing of 59 strains of Campylobacter fetus subsp. fetus

The susceptibilities of 59 Campylobacter fetus subsp. fetus isolates to eight antibiotics were studied by the agar dilution, E-test, and disk diffusion methods. None of the isolates were beta-lactamase producers. All were susceptible to ampicillin, gentamicin, imipenem, and meropenem as determined by the three methods, with MICs at which 90% of the isolates are inhibited (MIC90s) (determined by agar dilution) of 2, 1, < or = 0.06, and 0.12 microgram/ml, respectively. Twenty-seven percent of the isolates were resistant to tetracycline, with complete agreement between the agar dilution and disk diffusion results. The MIC90s determined by agar dilution were 2 micrograms/ml for erythromycin, 1 microgram/ml for ciprofloxacin, and 8 micrograms/ml for cefotaxime.

A pilot study on upper esophageal sphincter dilatation for the treatment of dysphagia in patients with oculopharyngeal muscular dystrophy

Upper esophageal sphincter (UES) dilatation was done for the treatment of moderate to severe dysphagia with a Maloney bougie in 14 patients with oculopharyngeal muscular dystrophy (OPMD) or with an achalasia dilator in three patients. The severity of dysphagia prior to UES dilatation was evaluated by a 15-point dysphagia score, a pharyngeal and esophageal manometry and a radionuclide pharyngoesophageal transit study. Using actuarial life table, the improvement rate after dilatation with Maloney bougie was 64.3% (95% CI 39.2-89.4) at 3- and 6-month follow-ups, and was 55.7% (95% CI 28.9-82.5) at 12- and 18-month follow-ups. At 3-month post-dilatation, we observed a significant reduction of the mean dysphagia score from 9.6 to 7.2 (P = 0.05). No significant manometric or radionuclide factors were found to predict effective dilatation. The results of this pilot study showed that UES dilatation with Maloney bougie or achalasia dilator may be an effective treatment of moderate dysphagia in patients with OPMD. However, further studies with larger sample sizes are needed to corroborate these results and to assess long-term outcome.

Structural and evolutionary relationships among chitinases of flowering plants

The analysis of nuclear-encoded chitinase sequences from various angiosperms has allowed the categorization of the chitinases into discrete classes. Nucleotide sequences of their catalytic domains were compared in this study to investigate the evolutionary relationships between chitinase classes. The functionally distinct class III chitinases appear to be more closely related to fungal enzymes involved in morphogenesis than to other plant chitinases. The ordering of other plant chitinases into additional classes mainly relied on the presence of auxiliary domains-namely, a chitin-binding domain and a carboxy-terminal extension-flanking the main catalytic domain. The results of our phylogenetic analyses showed that classes I and IV form discrete and well-supported monophyletic groups derived from a common ancestral sequence that predates the divergence of dicots and monocots. In contrast, other sequences included in classes I* and II, lacking one or both types of auxiliary domains, were nested within class I sequences, indicating that they have a polyphyletic origin. According to phylogenetic analyses and the calculation of evolutionary rates, these chitinases probably arose from different class I lineages by relatively recent deletion events. The occurrence of such evolutionary trends in cultivated plants and their potential involvement in host-pathogen interactions are discussed.

Evaluation of a non-isotopic polymerase chain reaction assay for detection in clinical specimens of herpes simplex virus type 2 DNA. Canadian Women's HIV Study Group

BACKGROUND

PCR assays for detection of herpes simplex virus DNA sequences in clinical specimens are more sensitive than cell culture.

OBJECTIVE

A non-isotopic PCR assay (glycoprotein B HSV-2 assay, Roche Molecular Systems) for detection of HSV-2 DNA sequences was evaluated on 234 clinical specimens.

STUDY DESIGN

A total of 125 patients (73 women, 40 men, 12 unknown) provided 162 samples contained in viral transport medium. Samples were first inoculated in cell culture, centrifuged at 12,000 x g, lyzed and kept frozen. A total of 77 women provided 42 cervicovaginal lavages and 30 vaginal tampons that were lyzed, tested with two isotopic HSV-2 PCR assays and kept frozen. All these samples were subsequently thawed and amplified with the glycoprotein B HSV-2 assay using generic primers for HSV glycoprotein B gene. Amplicons were captured on microplates with a HSV-2-specific probe and were detected with avidin-peroxidase and substrate.

RESULTS

Of the 162 samples submitted to viral culture, HSV-2 was isolated from 73 while 89 did not contain HSV-2. All the 73 specimens with culture-proven HSV-2 infections tested positive with glycoprotein B HSV-2 assay (sensitivity of 100%). Herpesviruses other than HSV-2 were isolated from 34 samples that were negative with glycoprotein B HSV-2 assay. Two culture-negative samples tested positive in the glycoprotein B HSV-2 assay (specificity of 98.7%). The latter samples could not be retested in confirmatory isotopic HSV-2 PCR tests. HSV-2 DNA sequences could also be detected directly in cervical lavages or vaginal tampons from 13 women with the glycoprotein B HSV-2 assay.

CONCLUSION

Detection and typing of HSV-2 in clinical samples, including those collected in viral transport medium, can be accomplished with PCR assays using the AMPLICOR format.

Lack of effect of NaCl and/or metoclopramide on exogenous (13C)-glucose oxidation during exercise

The purpose of this study was to compare the oxidation rate of ingested glucose during prolonged exercise, without and with the addition of sodium to the solution. The effect of metoclopramide, a drug which favors gastric emptying, was also investigated since gastric emptying could be a factor limiting the bioavailability of ingested glucose. Six subjects performed four bouts of exercise of 2 hours each at 64 +/- 4% VO2max on a cycle ergometer during which they ingested 100 g of glucose enriched with 13C, without (trials 1 and 3) and with (trials 2 and 4) addition of 25 mmol.l(-1) of NaCl. The glucose solution was ingested in four equal volumes (175 ml containing 25 g of glucose) at 0, 30, 60 and 90 min of the exercise period. For the trials 3 and 4, the subjects were given 10 mg of metoclopramide orally 60 min before the beginning of exercise. The VO2, VCO2 and heart rate were similar in response to exercise between the four trials. No significant difference was observed between trials for the oxidation rates of ingested glucose during the first as well as the second hour of exercise. Over the 120 min of exercise, the amounts of exogenous glucose oxidized were 52.0 +/- 9.6, 54.3 +/- 10.9, 52.7 +/- 12.3 and 53.3 +/- 10.4 grams for trials 1 to 4, respectively. The contribution of exogenous glucose oxidation to the energy yield represented 13.0 +/- 1.8% without and 13.2 +/- 1.9% with addition of NaCl. The amounts of endogenous carbohydrate and fat oxidized were also similar in the four trials. These results suggest that neither the addition of NaCl to glucose solutions nor the ingestion of metoclopramide increases the contribution of the oxidation of ingested glucose to the total energy yield during prolonged exercise.

Clinical usefulness of intravenous human immunoglobulins in invasive group A Streptococcal infections: case report and review

The spectrum of invasive Streptococcus pyogenes (group A streptococcus) infections includes bacteremia, toxic shock syndrome, and necrotizing fasciitis or myositis. We report the successful use of intravenous immunoglobulins in conjunction with antibiotics and surgery in a case of necrotizing myositis, toxic shock, and bacteremia. A literature review revealed that three other patients with invasive group A streptococcal infections had been treated with immunoglobulins: one adult patient had toxic shock syndrome, one had necrotizing fasciitis, and one child had septic arthritis. On the basis of this report and the review, we suggest that intravenous immunoglobulins may be useful in the treatment of all forms of invasive group A streptococcal infections associated with toxic shock syndrome.