Induction of mucosal and systemic antibody specific for SeMF3 of Streptococcus equi by intranasal vaccination using a sucrose acetate isobutyrate based delivery system

Streptococcus equi causes equine strangles, a highly contagious disease of the upper respiratory tract. The antiphagocytic surface protein SeM is strongly immunogenic and evokes mucosal and systemic antibodies during convalescence. The present study investigated the potential of sucrose acetate isobutyrate (SAIB); a high viscosity excipient that provides controlled release of biologically active substances, to enhance antibody responses following intranasal immunization of horses with a 108 a.a. peptide of SeM (SeMF3). SeMF3-SAIB was administered intranasally to each of the 11 adult horses on days 0 and 28. A second group of seven horses was vaccinated with SeMF3 alone. SAIB enhanced the mucosal and systemic immunogenicity of SeMF3, whereas SeMF3 by itself stimulated only a shortlived mucosal IgA and no systemic response. Moreover, nasal mucosal responses of horses immunized with SeMF3-SAIB were qualitatively and quantitatively similar to those observed in convalescent horses and involved similar linear epitopes of SeM. Epitope analysis also suggested that the nasal response was different from that observed in serum. A booster response was obtained after the second vaccination. These results suggest that SAIB has potential as a vehicle for intranasal immunization of horses with antigenic peptides.

Optimization of cationic lipid/DNA complexes for systemic gene transfer to tumor lesions

Intravenous (i.v.) administration of cationic lipid N-[( 1-(2-3-dioleyloxy)propyl)]-N-N-N-trimethylammonium chloride (DOTMA)-based transfection complexes in mice with subcutaneous squamous cell tumors yielded plasmid delivery and expression in tumor lesions. The efficiency of gene transfer in tumors was significantly lower than in the lung. This was consistent with low plasmid levels associated with the tumor, suggesting that plasmid delivery to the tumor site was a limiting factor. Lowering the lipid/DNA charge ratio from 5:1 to 0.8:1 (+/-) did not change DNA levels in tumor but significantly reduced DNA levels in lung. However, expression levels were significantly reduced in both tissues at lower lipid/DNA charge ratios. Complexes prepared from small unilamellar liposomes gave significantly lower expression levels in the lungs but similar expression levels in tumors when compared to complexes prepared from larger unilamellar liposomes. The small liposome complexes were better tolerated than large liposome complexes. Varying the cationic lipid to colipid (cholesterol or DOPE) molar ratio from 4: 1 to 1: 1 significantly reduced expression levels in both tumor and lung. Cationic lipid substitution, using a cholesterol cationic lipid, diethyldiamino-carbamyl-cholesterol instead of DOTMA, produced reduced expression in all other tissues except tumor. Incorporation of PEG into preformed transfection complexes reduced DNA delivery to lung, increased circulation half-life, and enhanced DNA delivery to tumor. In a lung metastatic mouse tumor model, where the accessibility of the i.v. administered transfection complexes to tumor lesions should be less challenging, DOTMA: CHOL complexes (4: 1 lipid to colipid molar ratio, 3: 1 +/- lipid to plasmid charge ratio) were preferentially localized in tumor lesions. These data demonstrate that systemic gene transfer to distal tumor sites by lipid/ DNA complexes may be limited by low plasmid delivery. Modifying the chemical surface properties of transfection complexes enhanced both DNA delivery and expression in tumor and is one approach that may overcome limitations.

Clinical infection control in gene therapy: a multidisciplinary conference

Gene therapy is being studied for the treatment of a variety of acquired and inherited disorders. Retroviruses, adenoviruses, poxviruses, adeno-associated viruses, herpesviruses, and others are being engineered to transfer genes into humans. Treatment protocols using recombinant viruses are being introduced into clinical settings. Infection control professionals will be involved in reviewing the safety of these agents in their clinics and hospitals. To date, only a limited number of articles have been written on infection control in gene therapy, and no widely available recommendations exist from federal or private organizations to guide infection control professionals. The goals of the conference were to provide a forum where gene therapy experts could share their perspectives and experience with infection control in gene therapy and to provide an opportunity for newcomers to the field to learn about issues specific to infection control in gene therapy. Recommendations for infection control in gene therapy were proposed.

A large-scale North American study of fungal isolates from nails: the frequency of onychomycosis, fungal distribution, and antifungal susceptibility patterns

BACKGROUND

Onychomycosis, a fungal infection of the nail bed, is responsible for up to 50% of nail disorders. Although several surveys have been conducted in different parts of the world, there have been no multicenter epidemiologic surveys of onychomycosis in North America.

OBJECTIVE

A 12-center study was undertaken to (1) determine the frequency of onychomycosis, (2) identify organisms recovered from the nails, and (3) determine the antifungal susceptibility of isolates.

METHODS

A total of 1832 subjects participated in this study and completed a comprehensive questionnaire, and nail clippings were collected for potassium hydroxide examination and culturing.

RESULTS

The frequency of onychomycosis, as defined by the presence of septate hyphae on direct microscopy and/or the recovery of a dermatophyte, was found to be 13.8%. In general, the dermatophyte isolates were susceptible to the antifungals tested.

CONCLUSION

Because of the limited number of large-scale studies, the baseline incidence is not firmly established. However, the higher frequency of onychomycosis in this study may confirm the suspected increase in incidence of disease in North America.

Xenobiotic metabolism by cultured primary porcine hepatocytes

Considering the large yield of viable cells comparable to human liver, primary porcine hepatocytes offer a valuable resource for constructing a bioartificial liver device. In this study, the ability of cultured primary porcine hepatocytes to detoxify xenobiotics has been examined using various known substrates of cytochrome P450 isoenzymes and UDP-glucuronosyltransferases. Present investigation demonstrated the stability of the isoenzymes responsible for the metabolism of diazepam in native state and stabilization of other isoenzymes, as judged by ethoxycoumarin o-dealkylase (ECOD), ethoxyresorufin o-dealkylase (EROD), benzyloxyresorufin o-dealkylase (BROD), and pentoxyresorufin o-dealkylase (PROD) activities following induction in culture environment, for a period of 8 days. Resorufin O-dealkylase activities were found to be the most unstable and deteriorated within first 5 days in culture. These activities were restored following induction with 3-methylcholanthrene (3-MC) or sodium phenobarbital (PB) to 20-fold of 1 activity for EROD, and 60 and 174% of day 1 activity for PROD and BROD on day 8, respectively. Metabolism of methoxyresorufin was most strikingly increased following induction with 3-MC to approximately 60-fold of day 1 activity, on day 8. UDP-glucuronosyltransferase-dependent glucuronidation of phenol red, however, stayed intact during the course of our study without induction. Our study indicated that porcine hepatocytes in vitro maintain many important liver-specific functions including detoxification (steady state and inducibility).

Design of a new surgical approach for ventricular remodeling to relieve ischemic mitral regurgitation: insights from 3-dimensional echocardiography

BACKGROUND

Mechanistic insights from 3D echocardiography (echo) can guide therapy. In particular, ischemic mitral regurgitation (MR) is difficult to repair, often persisting despite annular reduction. We hypothesized that (1) in a chronic infarct model of progressive MR, regurgitation parallels 3D changes in the geometry of mitral leaflet attachments, causing increased leaflet tethering and restricting closure; therefore, (2) MR can be reduced by restoring tethering geometry toward normal, using a new ventricular remodeling approach based on 3D echo findings.

METHODS AND RESULTS

We studied 10 sheep by 3D echo just after circumflex marginal ligation and 8 weeks later. MR, at first absent, became moderate as the left ventricle (LV) dilated and the papillary muscles shifted posteriorly and mediolaterally, increasing the leaflet tethering distance from papillary muscle tips to the anterior mitral annulus (P<0.0001). To counteract these shifts, the LV was remodeled by plication of the infarct region to reduce myocardial bulging, without muscle excision or cardiopulmonary bypass. Immediately and up to 2 months after plication, MR was reduced to trace-to-mild as tethering distance was decreased (P<0.0001). LV ejection fraction, global LV end-systolic volume, and mitral annular area were relatively unchanged. By multiple regression, the only independent predictor of MR was tethering distance (r(2)=0.81).

CONCLUSIONS

Ischemic MR in this model relates strongly to changes in 3D mitral leaflet attachment geometry. These insights from quantitative 3D echo allowed us to design an effective LV remodeling approach to reduce MR by relieving tethering.

Problem gamblers: do GPs want to intervene?

AIM

To survey GPs' attitudes towards problem gamblers and knowledge to successfully intervene.

METHODS

100 GPs, randomly selected for gender and geographical distribution, were anonymously surveyed by questionnaire through the Royal New Zealand College of General Practitioners.

RESULTS

80 GPs responded (80% of those surveyed). There was strong support (85%) for problem gambling being within a GP's mandate, for involvement in treatment of problem gambling (72%) and for their having a role in supporting a family where a member has a gambling problem (80%). There was less confidence in: raising the issue of gambling with patients (53%), in knowledge of resources (38%) and in having the necessary training to intervene (19%).

CONCLUSIONS

GPs see problem gambling as a legitimate role for their intervention, however, they have concerns around their competency and knowledge of resources. The provision of undergraduate and postgraduate training may assist to remove barriers to an accepted role in primary health.

Phylogenetics of flowering plants based on combined analysis of plastid atpB and rbcL gene sequences

Following (1) the large-scale molecular phylogeny of seed plants based on plastid rbcL gene sequences (published in 1993 by Chase et al., Ann. Missouri Bot. Gard. 80:528-580) and (2) the 18S nuclear phylogeny of flowering plants (published in 1997 by Soltis et al., Ann. Missouri Bot. Gard. 84:1-49), we present a phylogenetic analysis of flowering plants based on a second plastid gene, atpB, analyzed separately and in combination with rbcL sequences for 357 taxa. Despite some discrepancies, the atpB-based phylogenetic trees were highly congruent with those derived from the analysis of rbcL and 18S rDNA, and the combination of atpB and rbcL DNA sequences (comprising approximately 3000 base pairs) produced increased bootstrap support for many major sets of taxa. The angiosperms are divided into two major groups: noneudicots with inaperturate or uniaperturate pollen (monocots plus Laurales, Magnoliales, Piperales, Ceratophyllales, and Amborellaceae-Nymphaeaceae-Illiciaceae) and the eudicots with triaperturate pollen (particularly asterids and rosids). Based on rbcL alone and atpB/rbcL combined, the noneudicots (excluding Ceratophyllum) are monophyletic, whereas in the atpB trees they form a grade. Ceratophyllum is sister to the rest of angiosperms with rbcL alone and in the combined atpB/rbcL analysis, whereas with atpB alone, Amborellaceae, Nymphaeaceae, and Illiciaceae/Schisandraceae form a grade at the base of the angiosperms. The phylogenetic information at each codon position and the different types of substitutions (observed transitions and transversions in the trees vs. pairwise comparisons) were examined; taking into account their respective consistency and retention indices, we demonstrate that third-codon positions and transitions are the most useful characters in these phylogenetic reconstructions. This study further demonstrates that phylogenetic analysis of large matrices is feasible.

Myocardial perfusion and wall motion in infarction border zone: assessment by myocardial contrast echocardiography

Several mechanisms have been proposed to explain the decreased wall motion (WM) at the borders of myocardial infarction (MI). We used myocardial contrast echocardiography (MCE) to investigate the relation of perfusion to WM in infarcted border zones (BZs) 6 weeks after MI in 5 sheep. After quantifying the extent of WM abnormality and the perfusion defect, normal (NL), infarcted, and BZs were defined. Peak intensity after contrast was measured in acoustic units (AU). Radiolabeled microspheres were injected to measure regional blood flow. The heart was stained with 2,3, 5-triphenyltetrazolium chloride (TTC). The perfusion defect on MCE was 33% +/- 7% of the total myocardial area and correlated well with TTC (r = 0.92, P <.03). The BZ was 8% +/- 5% of the total myocardial area. Peak intensity after contrast was decreased in MI compared with BZ and NL (MI: 2.5 +/- 1.9 AU, BZ: 8.0 +/- 3.8 AU, P <.005; NL: 10.2 +/- 6.9 AU, P <.02) and comparable in NL and BZ. The blood flow measured by microspheres was not different in NL and BZ but was decreased in MI (NL: 1.6 mL/g/min, BZ: 1.5 +/- 0.5 mL/g/min, MI: 0.7 +/- 0.5 mL/g/min; P <.0001). In this model of chronic ovine MI, the BZ was small and its perfusion was preserved. These findings support the hypothesis that tethering of normal myocardial segments explains the abnormal wall motion noted at the borders of MI.

Direct visualization of HIV-1-specific cytotoxic T lymphocytes during primary infection

OBJECTIVE

HIV-specific cytotoxic T lymphocytes (CTL) are believed to play an important role in containing viral replication throughout HIV-1 infection. Previous studies have attempted to quantify the HIV-1-specific CTL precursor frequency during primary HIV infection by using limiting dilution analysis, which almost certainly underestimates the true CTL frequency. Here we use a relatively new technique to quantify HIV-specific CD8 T cells in primary HIV infection.

METHODS

We have used soluble tetrameric complexes of HLA class I molecules complexed with HIV epitope peptides to study the dynamics and frequency of HIV-specific CD8 T cells in relation to plasma viral load in early HIV infection, in three patients with a highly focused HIV-specific CTL response.

RESULTS

We show that the frequencies of HIV-1-specific CD8 T cells in acute infection are significantly higher than previously documented and can be demonstrated well before full seroconversion. These studies also confirm the immunodominance of the B27-restricted response in HIV infection and demonstrate a close temporal relationship between the numbers of circulating HIV-specific CD8 T cells and viral load.

CONCLUSIONS

These findings strongly suggest that HIV-1-specific CD8 T cells are responding directly to the level of viral replication in early HIV infection and are a major factor in its control. In addition, the data indicate that immunodominance for CD8 T-cell responses is established in the acute phase of HIV infection.

Effect of long-term caloric restriction on GLUT4, phosphatidylinositol-3 kinase p85 subunit, and insulin receptor substrate-1 protein levels in rhesus monkey skeletal muscle

Caloric restriction (CR), a reduction in calorie intake without malnutrition, improves insulin sensitivity in various species, including mice, rats, rhesus and cynomolgus monkeys, and humans. Skeletal muscle is quantitatively the most important tissue for blood glucose clearance. Therefore, we assessed the effect of 6 years of CR (30% reduction in calorie intake) in male rhesus monkeys (14-20 years old) on muscle expression of several proteins involved in insulin action. Whole body insulin sensitivity (assessed by Modified Minimal Model) was significantly increased in CR relative to Control monkeys. CR did not alter the expression of GLUT4 glucose transporter or phosphatidylinositol-3 kinase p85 subunit (PI3K). Insulin receptor substrate-1(IRS-1) abundance tended to be greater for CR compared to Control monkeys (p = .051), but correlational analysis revealed no association between IRS-1 and insulin sensitivity (r2 = .075, p = .271). These findings indicate that the CR-induced increase in insulin sensitivity in rhesus monkeys is unrelated to alterations in GLUT4, P13K, and IRS-1 abundance.

Remodeling of an acellular collagen graft into a physiologically responsive neovessel

Surgical treatment of vascular disease has become common, creating the need for a readily available, small-diameter vascular graft. However, the use of synthetic materials is limited to grafts larger than 5-6 mm because of the frequency of occlusion observed with smaller-diameter prosthetics. An alternative to synthetic materials would be a biomaterial that could be used in the design of a tissue-engineered graft. We demonstrate that a small-diameter (4 mm) graft constructed from a collagen biomaterial derived from the submucosa of the small intestine and type I bovine collagen has the potential to integrate into the host tissue and provide a scaffold for remodeling into a functional blood vessel. The results obtained using a rabbit arterial bypass model have shown excellent hemostasis and patency. Furthermore, within three months after implantation, the collagen grafts were remodeled into cellularized vessels that exhibited physiological activity in response to vasoactive agents.

Promoting tobacco cessation in primary care practice

Promoting tobacco cessation is an important part of the work of clinicians and staff in primary care practice. This article describes the significant public health impact of helping patients quit using tobacco through the use of an effective clinic-based intervention. The most effective strategies are to develop organization commitment, ask every patient about tobacco use at every visit and document it, advise all tobacco users to quit, assess readiness to quit, provide at least brief behavioral counseling, provide follow-up soon after quit date, conduct at least basic evaluations of each component of the process, and assess the quit rate for the practice as a whole.

Patients' perceived benefit from and satisfaction with asthma-related pharmacy services

OBJECTIVE

To determine whether patients targeted to receive intervention from an asthma management program reported receiving more services and had greater perceived benefit and satisfaction with those services compared with asthma patients not targeted by the program.

DESIGN

Mailed survey.

SETTING

Community pharmacy.

PATIENTS

471 community-based patients receiving asthma medications from 44 intervention pharmacies and 1,164 patients from 46 usual care (control) pharmacies.

MAIN OUTCOME MEASURES

Five-point agreement scale measuring asthma services received, perceived value of the services, and satisfaction.

RESULTS

Usable surveys were received from 39.0% of intervention patients and 42.4% of controls. There were no statistically significant differences between groups in the frequency of provision of listed services. Approximately 60% of respondents from both groups received written materials on asthma medications and 54% received inhaler counseling; both were rated high for perceived benefit. Fewer than 20% reported being counseled about asthma triggers. Fewer than 5% reported pharmacists talking to physicians on their behalf. General satisfaction with pharmacy services was high (78.2% agree or strongly agree), but not statistically different between groups. More than 65% believed that pharmacists spend enough time counseling patients. Several comments indicated that patients did not expect or ask for information because they were unaware that services were available and/or they had already been counseled by their physician. Responses to the statement "my asthma is better controlled because of help given to me by the pharmacist" were equivocal and not different between groups.

CONCLUSION

Overall, there were few differences between groups. General satisfaction with pharmacy services is high, but patients' perceived benefit and satisfaction with cognitive services is lower. Increased public awareness of pharmacists' capabilities and a more proactive approach to providing cognitive services is needed.

Systemic inhibition of tumor growth and tumor metastases by intramuscular administration of the endostatin gene

Tumors require ongoing angiogenesis to support their growth. Inhibition of angiogenesis by production of angiostatic factors should be a viable approach for cancer gene therapy. Endostatin, a potent angiostatic factor, was expressed in mouse muscle and secreted into the bloodstream for up to 2 weeks after a single intramuscular administration of the endostatin gene. The biological activity of the expressed endostatin was demonstrated by its ability to inhibit systemic angiogenesis. Moreover, the sustained production of endostatin by intramuscular gene therapy inhibited both the growth of primary tumors and the development of metastatic lesions. These results demonstrate the potential utility of intramuscular delivery of an antiangiogenic gene for treatment of disseminated cancers.

Inhibition of eosinophil rolling and recruitment in P-selectin- and intracellular adhesion molecule-1-deficient mice

To determine the relative in vivo importance of endothelial expressed adhesion molecules to eosinophil rolling, adhesion, and transmigration, we have induced eosinophilic peritonitis using ragweed allergen in P-selectin-deficient, intracellular adhesion molecule-1 (ICAM-1)-deficient and control wild-type mice. Circulating leukocytes visualized by intravital microscopy exhibited reduced rolling and firm adhesion in P-selectin-deficient mice and reduced firm adhesion in ICAM-1-deficient mice. Eosinophils exhibited reduced rolling and firm adhesion to endothelium in P-selectin-deficient mice. Eosinophil recruitment in P-selectin-deficient mice ( approximately 75% inhibition of eosinophil recruitment) and ICAM-1-deficient mice ( approximately 67% inhibition of eosinophil recruitment) was significantly reduced compared with wild-type mice. Eosinophil recruitment was not completely inhibited in P-selectin/ICAM-1 double-mutant mice (eosinophil recruitment inhibited approximately 62%). However, pretreatment of P-selectin/ICAM-1-deficient mice with an anti-vascular cell adhesion molecule (VCAM) antibody induced near complete inhibition of eosinophil recruitment. Overall, these studies show that eosinophil rolling and firm adhesion is significantly reduced in P-selectin-deficient mice and that P-selectin, ICAM-1, and VCAM are important to eosinophil peritoneal recruitment after ragweed challenge.

Inhibition of pulmonary eosinophilia in P-selectin- and ICAM-1-deficient mice

Adhesion molecule expression by pulmonary endothelial cells is considered to play an important role in the recruitment of circulating leukocytes to sites of inflammation in the lung. We have used P-selectin- and intercellular adhesion molecule type 1 (ICAM-1)-deficient mice to determine whether these adhesion molecules are important to pulmonary eosinophil recruitment after allergen challenge. There was a significant inhibition of lung tissue eosinophil recruitment in ICAM-1-deficient mice (approximately 84% inhibition compared to wild-type mice) and P-selectin-deficient mice (approximately 67% inhibition compared to wild-type mice) 3 h after allergen challenge. The number of bronchoalveolar lavage (BAL) eosinophils in P-selectin-deficient and ICAM-1-deficient mice was also significantly reduced compared with wild-type mice. Levels of BAL eosinophil peroxidase (EPO) were significantly lower in ICAM-1-deficient mice (0.21 +/- 0.03 EPO units) compared with wild-type mice (3.34 +/- 0.65 EPO units). There was no significant difference in the degree of inhibition of eosinophil recruitment in ICAM-1-deficient mice at the three time points (3, 12, and 24 h) of study after allergen challenge. However, in P-selectin-deficient mice there was a decline in the degree of inhibition of eosinophil recruitment from 3 h (67% inhibition) and 12 h (72% inhibition) postchallenge, to 24 h postchallenge (38% inhibition), suggesting that other adhesion molecules may be playing a more prominent role than P-selectin at later time points. These studies suggest an important role for ICAM-1 and P-selectin in eosinophil recruitment to the lung after allergen challenge.

Malignant mixed Müllerian tumors of the uterus: a clinicopathologic, DNA flow cytometric, p53, and mdm-2 analysis of 44 cases

AIM

The authors retrospectively analyzed the prognostic significance of p53, mdm-2, DNA ploidy, S-phase fraction (SPF), and traditional clinical and pathologic factors in patients with malignant mixed Müllerian tumors (MMMT) of the uterus.

METHODS

Between 1970 and 1995, 44 uterine tumors were diagnosed as MMMT (21 stage I, 2 stage II, 10 stage III, and 11 stage IV). Thirty-two were homologous type and 12 were heterologous type. DNA flow cytometry and immunohistochemical analysis for p53 and mdm-2 overexpression were performed on paraffin-embedded archival tissue.

RESULTS

68% of the tumors were nondiploid and 61% had an SPF greater than 10%. Sixty-one percent overexpressed p53 and 25% were mdm-2-positive. Furthermore, 91% of the tumors had a mitotic count greater than 10/10 hpf and 95% had high-grade cytologic atypia. Twenty-seven (61%) patients died of tumor and 6 (14%) died of intercurrent disease. Eleven (25%) patients are alive with no evidence of disease. The median follow-up for patients still alive was 59 months (range, 28-178 months). The overall 5-year survival rate was 38%. In a univariate analysis that included stage, histologic type, DNA ploidy, SPF, p53, mdm-2, mitotic index, and age, and with survival as the end point, only stage reached statistically prognostic significance.

CONCLUSION

The majority of the tumors had obvious signs of aggressiveness such as high grade, high mitotic count, nondiploid pattern, high SPF, and overexpression of p53. This study found that stage is the most important prognostic factor for survival in MMMTs of the uterus.

Environmental Awareness, Economic Orientation, and Farming Practices: A Comparison of Organic and Conventional Farmers

/ This study examines similarities and differences between organic and conventional farmers. We explore the factors that underlie farmers' conservation attitudes and behaviors, including demographic and farm characteristics, awareness of and concern for environmental problems associated with agriculture, economic orientation toward farming, and self-reported conservation practices. A series of intensive personal interviews was conducted with 25 farmers in Washtenaw County, Michigan, USA, using both qualitative and quantitative survey methods. The findings indicate that both groups of farmers share a concern for the economic risks associated with farming, although the organic farmers reported a significantly greater concern for long-term sustainability and a greater willingness to incur present risk to gain future benefits. Organic farmers expressed a greater awareness of and concern for environmental problems associated with agriculture. Organic farmers also scored significantly higher on a multifaceted measure of conservation practices, although both groups had a fairly high adoption rate. Implications of these findings are discussed, relative to economic risks of farming, implications for new farmers, effectiveness of conservation education and government programs, and impact of farm size and crop diversity.KEY WORDS: Environmental attitudes; Conservation behaviors; Organic farming; Agricultural sustainability