Intranasal immunization with plasmid DNA-lipid complexes elicits mucosal immunity in the female genital and rectal tracts

The development of vaccines against pathogens transmitted across the genito-rectal mucosa that effectively stimulate both secretory IgA Abs and cytotoxic T lymphocytes in the genital tract and CTL in the draining lymph nodes (LN) has proven a major challenge. Here we report a novel, noninvasive approach of genetic vaccination via the intranasal route. Such vaccination elicits immune responses in the genital and rectal mucosa, draining LNs, and central lymphoid system. Intranasal immunization with plasmid DNA-lipid complexes encoding the model Ag firefly luciferase resulted in dissemination of the DNA and the encoded transcript throughout the respiratory and gastrointestinal tracts, draining LNs, and spleen. Complexing the plasmid DNA with the lipid DMRIE/DOPE enhanced expression of the encoded protein in the respiratory tract, increased specific secretory IgA Ab in the vaginal and rectal tracts, and increased the circulating levels of specific IgA and IgG. In addition, intranasal DNA immunization resulted in generation of Ag-specific CTL that were localized in the genital and cervical LNs and spleen. These results suggest that intranasal immunization with plasmid DNA-lipid complexes may represent a generic immunization strategy against pathogens transmitted across the genito-rectal and other mucosal surfaces.

Soft acrylic resin materials containing a polymerisable plasticiser II: water absorption characteristics

The main disadvantage of soft acrylic resin denture lining materials is the loss of plasticiser leading to gradual hardening. One possible solution to this problem is the use of a polymerisable plasticiser. A material based on such a plasticiser failed in clinical trials due to a combination of prolonged water uptake and low strength. Similar materials with improved strength have been developed and it is the aim of this study to investigate their water uptake characteristics. Water uptake from distilled water, an artificial saliva and 0.9 M saline has been determined for three experimental materials and 'Supersoft', a commercial plasticised acrylic resin denture lining material. Solubilities were determined after 6 months and diffusion coefficients calculated where appropriate. All the experimental materials had a lower uptake and solubility than 'Supersoft' in all solutions. For each material uptake was lower from solution than from distilled water. All diffusion coefficients were in the range expected for this type of material. The water uptake of the experimental materials was influenced by the relative hydrophilicity of the monomer used.

Experience with transdermal testosterone replacement therapy for hypogonadal men

BACKGROUND

None of the existing options for long-term testosterone replacement therapy (TRT) for hypogonadal men are ideal. Depot replacement at frequent intervals and implants are effective but invasive and inconvenient for the patient. Oral therapy results in poor hormone levels. Both are associated with undesirable metabolic changes. A transdermal formulation therefore represents a potential therapeutic advance for testosterone replacement.

OBJECTIVE

To carry out a clinical audit of the acceptability and efficacy as a treatment for hypogonadism of the first transdermal testosterone therapy available in the UK (Andropatch, SmithKline Beecham) compared with existing androgen replacement options.

PATIENTS AND MEASUREMENTS

Serum testosterone and questionnaire data on treatment efficacy, side-effects, therapy preference, sexual dysfunction and partner's attitudes to therapy were obtained from 50 hypogonadal men prescribed long-term testosterone replacement.

RESULTS

Eighty per cent of the men returned analysable questionnaires. Eighty-four per cent experienced adverse effects with transdermal therapy, most commonly dermatological problems; 22% of the sample elected to continue with transdermal therapy, 72% returned to depot and 5% returned to oral therapy. The reservoir patches were judged to be too large, uncomfortable, visually obtrusive and noisy. Testosterone levels were comparable to those obtained with depot replacement with the added advantage of a more physiological pharmacokinetic profile. Men taking oral preparations were consistently under-replaced.

CONCLUSIONS

Adverse events were substantially higher than reported from clinical trials but in keeping with the spectrum of yellow card reports received by the Committee on Safety of Medicines. The pharmacokinetic advantages are thus largely outweighed by low patient acceptability. In its present form transdermal therapy remains an expensive option for those who cannot tolerate depot testosterone replacement.

The second domain of the CD45 protein tyrosine phosphatase is critical for interleukin-2 secretion and substrate recruitment of TCR-zeta in vivo

The CD45 protein tyrosine phosphatase (PTPase) has been shown to regulate the activity of Lck and Fyn protein tyrosine kinases in T cells. However, it is not clear that these constitute the only CD45 substrates. Moreover, the manner by which PTPase activity and substrate recruitment are regulated, is poorly understood. Previous in vitro studies suggest that the first cytoplasmic PTPase domain (D1) of CD45 is the active PTPase, which may be regulated by an enzymatically inactive second PTPase domain (D2). However, the function of CD45 D2 in vivo is unknown. In this study, reconstitution of CD45(-) T cells with specific CD45 PTPase mutants allowed demonstration of a critical role for D2 in TCR-mediated interleukin (IL)-2 production. Specifically, replacement of CD45 D2 with that of the LAR PTPase to form a CD45/LAR:D2 chimera, abrogates CD45-dependent IL-2 production. This effect cannot be accounted for by loss of PTPase activity per se. The expression of D1 substrate-trapping mutants reveals an in vivo interaction between CD45 and TCR-zeta that is dependent on CD45 D2. Thus, cells expressing CD45 lacking D2 exhibit abnormal TCR-mediated signaling characterized by hyperphosphorylation of zeta and deficient ZAP-70 phosphorylation. These data suggest an essential role for CD45 D2 in TCR-regulated IL-2 production through substrate recruitment of the zeta chain.

Yes. No. Maybe. That's about as firm as the guidance gets over launching a provider-sponsored health plan. Strategy roundtable

Few participants in our roundtable on provider-sponsored health plans see them the same way. Some are gearing up new products, others are scaling back or getting out. Yet they agreed on one thing: The financial risks are tremendous.

Soft acrylic resin materials containing a polymerisable plasticiser I: mechanical properties

Conventional soft acrylic resin materials depend on the use of plasticisers for their compliance. In aqueous environments the plasticisers leach out causing the material to harden. Use of a polymerisable plasticiser has been shown to solve this problem. One such material was developed but failed mechanically during clinical trial. The aim of this study was to reformulate to produce a material with improved strength. Three different methacrylate monomers were used with two different levels of plasticiser, each monomer mix was used with the same copolymer powder at three powder/liquid ratios. Tensile strength, tear energy and hardness were measured and results compared with 'Supersoft', a proprietary plasticised acrylic resin soft lining material. All the experimental materials had a higher tensile strength than the original Parker/Braden material. The 30% plasticiser materials with the higher powder/liquid level had strength, tear energy and hardness values in the same range as 'Supersoft'. Materials of improved strength have been produced.

Catching goldfish: quality in qualitative research

This paper reviews the contribution of qualitative methods to health services research (HSR) and discusses some of the issues involved in recognizing quality in such work. The place of qualitative work is first defined by reference to Archie Cochrane's agenda for HSR and the limitations of the recent focus on randomized trials as the standard method. Health care practice involves large elements of improvisation which cannot be captured by evidence-based approaches. Qualitative methods offer ways of understanding this improvisation and of identifying more efficient and effective practices, as well as considering the traditional topics of equity and humanity. The methodological procedures of qualitative work reflect a long-established inductive tradition in scientific practice. The logic of grounded theory provides a contemporary specification. In its application, it is quite different from the methodological anarchy of postmodernism. The use of qualitative research and the theoretically stated generalizations which arise from it inform reflective work by health service managers, planners and clinicians.

Evaluating the effect of soft lining materials on the growth of yeast

STATEMENT OF PROBLEM

Soft lining materials continue to have a place in clinical removable prosthodontics. However, there is an increased probability of yeast colonization on soft lining materials.

PURPOSE

This study (1) assessed a method of evaluating the effect of long-term soft lining materials on the growth of yeast and (2) investigated the effect five soft lining materials had on the growth of three species of yeast.

MATERIAL AND METHODS

Coe Supersoft, Novus, and three experimental soft lining materials were investigated together with Candida albicans, Candida tropicalis, and Issatchenkia orientalis (formerly Candida krusei) yeasts. Strips of soft lining material incubated on blood agar plates were examined for inhibition of the growth of yeast. Soft lining materials soaked in sterile trypticase soya broth or water were inoculated with yeast and incubated. The change in colony forming units per milliliter from the initial load of yeast at 3 days was measured. Statistical analysis was performed with an independent paired Student t test.

RESULTS

Inhibition of yeast growth occurred for two soft lining materials. Despite the presence of sufficient viable organisms, differences between the initial load of yeast and the 3-day results were mostly small, both for the test and control groups, suggesting that the material does not support the growth of the tested yeast during this period.

CONCLUSIONS

The often described increased prevalence of yeast associated with soft lining materials in the oral environment is likely related to readily available nutrients in the mouth and the difficulty in maintaining and cleaning these materials.

Listening to parents. A national survey of parents with young children

OBJECTIVE

To document the child-rearing needs and pediatric health care experiences of parents with children from birth to 3 years old.

DESIGN

A nationally representatives sample of 2017 parents with children younger than 3 years using a 25-minute structured telephone questionnaire. Interviews were completed by 68% of the screened eligible respondents. The margin of sampling error for results at the 95% confidence level was +/- 3 percentage points.

RESULTS

Seventy-six percent of children younger than 3 years were reported by parents to be in excellent health; 88% had a regular source of pediatric health care. Seventy-one percent of parents who received special pediatric services rated their child's physician as excellent in providing good health care. Seventy-nine percent of parents reported they could use more information in at least 1 of 6 areas of child rearing, and 53% wanted information in at least 3 areas. Forty-two percent had talked with their child's physician about "nonmedical" concerns; 39% of parents read to or looked at a picture book with their child on a daily basis; 51% of parents set daily routines for meals, naps, and bedtime. Breast-feeding and reading to the child on a daily basis were much more likely if a physician encouraged parents to do so.

CONCLUSIONS

Most parents view the pediatric health care system as meeting the physical health needs of their young children. Parents want more information and support on child-rearing concerns, yet pediatric clinicians often fail to discuss nonmedical questions with them. The interventions of pediatric clinicians can positively affect parental behavior. Pediatric practices should consider creative ways to reconstitute and augment their current services and systems of care.

A case of treatment-refractory psychosis responsive to sertindole

Sertindole is an antipsychotic with atypical in vitro and ex vivo binding profiles and little propensity to cause extrapyramidal symptoms. However, its potential usefulness in the treatment of psychosis resistant to the 'classical' neuroleptics has not been determined. In the present study we used a double blind, placebo-controlled trial of sertindole and observed dramatic, sustained resolution of formerly-chronic positive and negative psychotic symptoms in a schizophrenic patient. This patient had averaged 2.5 inpatient admissions per year for the 8 years preceding initiation of sertindole therapy, but has had no hospitalizations or psychosis in the 3.5 years since. Improved cognitive function has also been documented. This preliminary, but controlled, experience suggests that sertindole may possess a spectrum of clinical activity distinct from that of the typical antipsychotic agent.

Adhesion and tear energy of a long-term soft lining material activated by rapid microwave energy

STATEMENT OF PROBLEM

Construction of dentures with permanent soft linings is time-consuming in the laboratory and extra costs are related to equipment and materials used.

PURPOSE

The purpose of this in vitro study was to determine whether using microwave energy to activate the polymerization of a silicone rubber denture soft lining material affected its properties.

MATERIAL AND METHODS

Tear energy and adhesive properties were measured in a tensile testing machine by using a pants leg tear test and peel specimens. Tear energy was measured for specimens polymerized conventionally (control) and for 3, 5, and 10 minutes in a microwave. Data were analyzed with one-way analysis of variance and a two-sample Student t test.

RESULTS

The multiple comparison test failed to show a significant difference in tear energy between 3 minutes microwave activation and conventional heat curing. However, 3 minutes microwave activation revealed a significantly stronger material when compared with 5 minutes and 10 minutes (p < 0.05). Application of a two-sample Student t test failed to demonstrate a significant difference between microwave energy and conventional heat activation groups in the adhesion test. In adhesion testing, all specimens presented cohesive failure.

CONCLUSIONS

This method of polymerization does not compromise the strength of a soft lining material and its adhesion to polymethyl methacrylate. This study suggests the use of 3 minutes 650 W microwave energy for processing a silicone soft lining material.

Mucosal immunization with DNA-liposome complexes

The mucosal surfaces represent the primary site for transmission of several viruses including HIV. To prevent mucosal transmission and dissemination to the regional lymph nodes, an effective HIV vaccine may need to stimulate immune responses at the genital and rectal mucosa. Optimal induction of mucosal immunity in general requires targeting antigens to the specialized antigen presenting cells of mucosal associated lymphoid tissues. The nasal mucosa may provide a simple, non-invasive route to deliver DNA encoding the introduced gene to stimulate mucosal immunity. As a first step to evaluate the feasibility of this approach, we have investigated as a model system, systemic and mucosal immune responses elicited to firefly luciferase generated by DNA immunization. Incorporating DNA into liposomes with cationic lipids enhanced luciferase expression in nasal tissue, and was associated with induction of a humoral response in serum and vaginal fluids and also a proliferative and cytotoxic T lymphocyte response in the spleen and iliac lymph nodes draining the genital and rectal mucosa.

Influence of additives on the water uptake of hydrosilanized silicone rubbers

Water uptake characteristics of a silicone polymer containing additives of varying solubility have been investigated. A hydrophobic silica, a sparingly soluble agent and a soluble catalyst were added to a stoichiometrically balanced hydrosilanized silicone polymer (the inherent absorption of which was 0.09 wt%). The diffusion coefficients for desorption of all materials were of the order 10(-6) cm2s-1, whereas the diffusion coefficients for absorption showed a decrease with increasing hydrophilicity and solubility of the additive. The greater the solubility of the additive, the more prolonged the uptake and the greater the deviation from classic diffusion theory.