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Photofragmentation translational spectroscopy was used to identify the primary and secondary reaction pathways in the KrF laser (248 nm) photodissociation of chlorine azide (ClN3) under collision-free conditions. Both the molecular channel producing NCl (X 3Σ,a 1Δ)+N2 and the radical channel producing Cl (2PJ)+N3 were analyzed in detail. Consistent with previously reported velocity map ion imaging experiments [N. Hansen and A. M. Wodtke, J. Phys. Chem. A 107, 10608 (2003)] a bimodal translational energy distribution is seen when Cl atoms are monitored at m/z=35(Cl+). Momentum-matched N3 counterfragments can be seen at m/z=42(N3+). The characteristics of the observed radical-channel data reflect the formation of linear azide radical and another high-energy form of N3 (HEF-N3) that exhibits many of the characteristics one would expect from cyclic N3. HEF-N3 can be directly detected by electron-impact ionization more than 100 μs after its formation. Products of the unimolecular dissociation of HEF-N3 are observed in the m/z=14(N+) and m/z=28(N2+) data. Anisotropy parameters were determined for the primary channels to be β=-0.3 for the NCl forming channel and β=1.7 and β=0.4 for the linear N3 and HEF-N3 forming channels, respectively. There is additional evidence for secondary photodissociation of N3 and of NCl. [ABSTRACT FROM AUTHOR]

Biofilm formation and cell-cell sensing by the pioneer dental plaque colonizer Streptococcus gordonii are dependent upon arginine. This study aimed to identify genetic factors linking arginine-dependent responses and biofilm formation in S. gordonii. Isogenic mutants disrupted in genes required for the biosynthesis or catabolism of arginine, or for arginine-dependent gene regulation, were screened for their ability to form biofilms in a static culture model. Biofilm formation by a knockout mutant of arcR, encoding an arginine-dependent regulator of transcription, was reduced to < 50% that of the wild-type whereas other strains were unaffected. Complementation of S. gordonii ∆arcR with a plasmid-borne copy of arcR restored the ability to develop biofilms. By DNA microarray analysis, 25 genes were differentially regulated in S. gordonii ∆arcR compared with wild-type under arginine-replete conditions including eight genes encoding components of phosphotransferase systems for sugar uptake. By contrast, disruption of argR or ahrC genes, which encode paralogous arginine-dependent regulators, each resulted in significant changes in the expression of more than 100 genes. Disruption of a gene encoding a putative extracellular protein that was strongly regulated in S. gordonii ∆arcR had a minor impact on biofilm formation. We hypothesize that genes regulated by ArcR form a critical pathway linking arginine sensing to biofilm formation in S. gordonii. Further elucidation of this pathway may provide new targets for the control of dental plaque formation by inhibiting biofilm formation by a key pioneer colonizer of tooth surfaces. [ABSTRACT FROM AUTHOR]

Background: Obesity is highly prevalent in African American women, especially those in the rural southern USA, resulting in persistent health disparities.Objective: To test the effectiveness of an evidence-based behavioural weight loss intervention delivered by community health advisors to African American women in the rural south.Design and Methods: Overweight or obese African American women (30-70 years) from eight counties in Mississippi and Alabama participated in a 24-month randomized controlled trial of an evidence-based behavioural weight loss programme augmented with community strategies to support healthy lifestyles (Weight Loss Plus, N = 154) compared to the weight loss programme alone (Weight Loss Only, N = 255). This study reports on 6-month outcomes on primary (weight change) and secondary (waist circumference, blood pressure, lipids, fasting blood glucose) outcomes, coinciding with the completion of the intensive weight loss phase.Results: Weight Loss Only participants lost an average of 2.2 kg (P < 0.001). Weight Loss Plus participants lost an average of 3.2 kg (P < 0.001). The proportion of the total sample that lost at least 5% of their body weight was 27.1% with no difference between treatment groups. Similarly, we observed statistically significant reductions in blood pressure, waist circumference and triglycerides in each treatment group, with no statistical differences between groups.Conclusion: Trained lay health staff and volunteers from the rural southern USA were able to deliver a translation of a high-intensity behavioural intervention targeted to African American women, resulting in clinically meaningful weight loss and improvement in other metabolic outcomes in a significant proportion of participants. [ABSTRACT FROM AUTHOR]

The Chafee-Infante equation is one of the canonical infinite-dimensional dynamical systems for which a complete description of the global attractor is available. In this paper we study the structure of the pullback attractor for a non-autonomous version of this equation, ut = uxx + λu - β(t)u3, and investigate the bifurcations that this attractor undergoes as λ is varied. We are able to describe these in some detail, despite the fact that our model is truly non-autonomous; i.e., we do not restrict to 'small perturbations' of the autonomous case. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the efficacy of topical ophthalmic aciclovir applied five times daily as a treatment for feline herpesvirus type 1 (FHV-1) keratitis in a group of cats in a first-opinion practice setting. Cats with ocular signs indicative of FHV-1 or Chlamydophila species infection, predominantly conjunctivitis and keratitis, were tested for FHV-1 antigen using an immunofluorescent technique on air-dried conjunctival swabs. They were first treated with topical chlortetracycline with efficacy against Chlamydophila species and then, in cases positive for FHV-1, with topical aciclovir. The time to recovery was determined and illustrated using a Kaplan-Meier plot. Three cats were infected with Chlamydophila species and showed a median time to recovery of 14 days (95 per cent confidence interval [Cl] ] 0 to 18 days), while 30 cats infected with FHV-1 showed a median time to recovery of 12 days (95 per cent Cl 10 to 14 days). The drug dose at which 50 per cent plaque reduction (ED50) occurred in a standard plaque reduction assay was determined in an in vitro study. This showed a mean (sd) ED50 of aciclovir of 25 (3.5) mg/ml compared with 0.4 (0.05) mg/ml for trifluorothymidine, a drug known to be efficacious against FHV-1. The study shows that even though aciclovir is generally considered to lack efficacy against ocular FHV-1 infection, when used frequently it can have a beneficial effect in FHV-1 conjunctivitis and keratitis. [ABSTRACT FROM AUTHOR]

Purpose. To determine, by a plaque reduction assay, the in vitro efficacy of novel antiviral agents in the treatment of feline herpes virus 1 (FHV-1) keratitis in the domestic cat ( Felis felis ) . Materials and methods. A standard plaque reduction assay was performed using a laboratory strain of FHV-1 and embryo-derived feline kidney cells to determine the in vitro efficacy of the antiviral drugs penciclovir (PCV), bromovinyldeoxyuridine (BVdU), and ( S )-9-(3-hydroxy-2-phosphonylmethoxypropyl) adenine (HPMPA) and to compare these with the drugs acyclovir (ACV) and trifluorothymidine (TFT). Efficacy was assessed by determining the dose of drug at which 50% plaque reduction was noted (ED 50 ). Results. HPMPA was found to have greatest antiviral activity (ED 50 0.07 µg/ml). ACV was least active (ED 50 24 µg/ml), while TFT was active with an ED 50 of 5.7 µg/ml. PCV and BVdU had intermediate activity (ED 50 1.6 and 1.7 µg/ml, respectively). Conclusions. This study suggests that the efficacy of HPMPA, BVdU, and penciclovir in cats with herpesviral keratitis should be determined in vivo as their efficacy in vitro was substantially greater than that of acyclovir, already shown to have demonstrable but limited clinical antiviral activity. [ABSTRACT FROM AUTHOR]

Objective: The enuresis alarm has been widely advocated as an effective intervention in the treatment of childhood nocturnal enuresis. Although there is a body of evidence concerning which pretreatment variables are related to outcome, there is little evidence relating to influential within-treatment variables. This study sought to examine a series of treatment variables against outcome. Material and Methods: A total of 66 children with severe primary nocturnal enuresis but with no day-time wetting were treated with a body-worn enuresis alarm. Pre- and within-treatment variables were collected. Success was considered to be 14 consecutive dry nights during a 16-week period. Results: A total of 54.5% of children achieved the success criterion, with 12.1% being classed as partial successes. Of the pretreatment variables, only low functional bladder capacity was significantly associated with failure. Inability to be woken by the alarm emerged as the most important within-treatment predictor of failure. Conclusions: The success of alarm treatment is dependent on the child's ability to be aroused by the alarm. Interestingly, of those who successfully became dry, 72.2% slept throughout the night for >80% of nights that they were dry, suggesting that the mode of action of the enuresis alarm is more complex than was previously thought. [ABSTRACT FROM AUTHOR]

Context: Independent practice associations (IPAs) are developing new methods of physician reimbursement to balance the objectives of encouraging individual productivity and clinical cooperation. The economic literature on payment incentives, derived from nonhealth industries, predicts that methods blending elements of fee-for-service and capitation will outperform exclusive reliance on either form of payment.Objective: To identify emerging payment methods within IPA physician groups that contract with managed care organizations.Design and Setting: Case studies of 7 large IPAs in the San Francisco, Calif, metropolitan region that served 826000 health maintenance organization (HMO) patients during the summer and fall of 1998.Main Outcome Measure: Payment methods of IPAs for primary care physicians, specialists, and physicians grouped by specialty department within the overall IPA structure.Results: All the IPAs contracted with multiple HMOs for the full range of primary and specialty care physicians' services but paid member physicians using methods that blended elements of fee-for-service and subcapitation. For primary care, most IPAs used monthly capitation adjusted for patient age, sex, and selected diagnoses, supplemented with fee-for-service payment for a wide range of visits and procedures, including patient visits in subacute, skilled nursing facility, emergency department, or home settings; for preventive care services; for office procedures requiring expensive supplies; and, most importantly, for borderline primary care procedures that either could be performed directly or referred to specialty care. All the IPAs paid specialty departments on a capitated basis and delegated to the departments responsibility for allocating the budget among individuals. Allocation mechanisms for individual specialists included adjusted fee-for-service, referral-based capitation, and blends of both.Conclusion: Our results and case studies indicate that IPAs are developing payment methods that blend elements of fee-for-service and capitation in innovative ways for primary care and specialty physicians. [ABSTRACT FROM AUTHOR]

There is a conflicting literature regarding the possible presence of adrenergic innervation of the retinal circulation. The effect of a histologically confirmed left superior cervical ganglionectomy on the total retinal blood flow in eight anaesthetised female cynomolgus monkeys was determined. Near total unilateral ocular sympathetic denervation was confirmed by ipsilateral miosis, supersensitivity of pupillary dilatation to topical phenylephrine and pupillary hyporesponsiveness to topical hydroxyamphetamine. Retinal vein diameters were measured from monochromatic photographs, maximum red cell velocities (Vmax) were measured with a helium-neon laser, using a bidirectional laser Doppler velocimeter technique, and the total retinal blood flow in each eye was determined by summation of measurements of flow in individual retinal veins. Mean (SEM) total retinal blood flow was 32.93 (1.49) and 30.41 (1.86) microliters/min in the eight sympathectomised and normal eyes respectively; the 9% (5%) difference was not statistically significant. Our study suggests that pharmacologically confirmed sympathetic denervation has little if any effect on resting total retinal blood flow. [ABSTRACT FROM PUBLISHER]

A highly sensitive, spontaneous Raman spectrometer designed for the study of vapors and other low-density samples is discussed. The high sensitivity is achieved by means of the novel combination of a multipass light cell and a high-temperature gasdynamic focusing system. A complete description of the apparatus is given, along with the results of a sensitivity test in ambient air, as well as results demonstrating gasdynamic focusing of a vapor and Raman transitions in such a sample. [ABSTRACT FROM AUTHOR]

Objectives: The relationship between menstrual and bowel symptoms, the overlap between the diagnoses of dysmenorrhea (DYS) and functional bowel disorder (FBD), and markers that may be useful in discriminating functional bowel disorders from DYS were studied in 383 women (20-40 yr of age). Methods: All women completed the NEO Personality Inventory at intake and completed the Moos' Menstrual Distress Questionnaire and a bowel symptom inventory every 3 months for 12 months. Prostaglandin levels were measured in vaginal dialysate on the first day of menses. Results: DYS was diagnosed in 19.8% of the total sample. Functional bowel disorder, defined as abdominal pain with altered bowel function, was diagnosed in 61% of the DYS group compared with 20% of controls (p < 0.05). Neuroticism scores were significantly higher in subjects with functional bowel disorder with or without DYS. However, bowel symptoms were significantly correlated with menstrual symptoms even after statistically controlling for the effects of neuroticism. Painful menses and water retention distinguished the DYS group from the functional bowel disorder group. Prostaglandin levels were elevated in women with DYS, but did not consistently differentiate the diagnostic groups. Conclusions: The strong covariation of menstrual and bowel symptoms, along with the overlap in diagnoses of DYS and function bowel disorder, suggest a common physiological basis. [ABSTRACT FROM AUTHOR]

A standardised inventory of stressful life events and a bowel symptom questionnaire were administered at three month intervals for one year to 383 women who were unselected with respect to bowel symptoms. A NEO Personality Inventory was given initially to assess neuroticism. Subjects who satisfied restrictive diagnostic criteria for irritable bowel syndrome were compared with those who complained of abdominal pain plus altered bowel habits but who did not meet restrictive diagnostic criteria (functional bowel disorder) and with controls without bowel dysfunction. The irritable bowel group showed significantly higher levels of stress than the other two groups even when the confounding effects of neuroticism were statistically controlled for. Time lagged correlations showed that stress in one three month interval was significantly correlated with bowel symptoms in the subsequent three month interval for all groups. The slope of the regression line relating stress to bowel symptoms was significantly steeper for the irritable bowel group than for the other two groups at three and six months, suggesting that subjects with irritable bowel syndrome show a greater reactivity to stress. Stress scores were also significantly correlated with the number of disability days and the number of medical clinic visits for bowel symptoms. [ABSTRACT FROM PUBLISHER]

A dimethyl siloxane triacetoxy terminated silane, Type A adhesive, was modified with the base component of a medium grade polydimethyl siloxane with vinyl groups, MDX 4-4210, to produce a more pliable maxillofacial prosthesis. Force- displacement curves of various ratios of Type A adhesive/MDX 4-4210 were determined and compared with force-displacement curves obtained from human subjects. Within the force range of 0.4 to 1.2 N, the force-displacement slopes obtained on human subjects compared favourably with some of the Type A adhesive! MDX 4-4210 test specimens. The force-displacement slopes for the elastomers and humans were not in agreement for forces below 0.4 N. [ABSTRACT FROM AUTHOR]

A dimethyl siloxane triacetoxy terminated silane, Type A adhesive, was modified with the base component of a medium grade polydimethyl siloxane with vinyl groups, MDX 4-4210, to produce a more pliable maxillofacial prosthesis. The mechanical properties of samples with various Type A adhesive/MDX 4-4210 ratio were determined. Addition of the MDX 4-4210 base decreased the hardness, modulus, and ultimate tensile strength, while the percentage elongation increased. The initial tear strength was relatively constant for the various except for the 50/50 mix, where a 50% decrease was observed. The ability to obtain different mechanical properties by using various ratios of Type A adhesive and MDX 4-4210 could result in the production of maxillofacial prostheses which will more closely stimulate the properties of facial tissues. [ABSTRACT FROM AUTHOR]

Context: Medical groups are growing and merging to improve efficiency and bargaining leverage in the competitive managed care environment. An increasing number are affiliating with physician practice management (PPM) firms that offer capital financing, expertise in utilization management, and global capitation contracts with health insurance entities. These physician organizations provide an alternative to affiliation with a hospital system and to individual physician contracting with health plans.Objective: To describe the growth, structure, and strategy of PPM organizations that coordinate medical groups in multiple markets and contract with health maintenance organizations (HMOs).Design: Case studies, including interviews with administrative and clinical leaders, review of company documents, and analysis of documents from investment bankers, the Securities and Exchange Commission, and industry observers.Setting: Medical groups and independent practice associations (IPAs) in California and New Jersey affiliated with MedPartners, FPA Medical Management, and UniMed.Outcome Measures: Growth in number of primary care and specialty care physicians employed by and contracting with affiliated medical groups; growth in patient enrollment from commercial, Medicare, and Medicaid HMOs; growth in capitation and noncapitation revenues; structure and governance of affiliated management service organizations and professional corporations; and contracting strategies with HMOs.Results: Between 1994 and 1996, medical groups and IPAs affiliated with 3 PPMs grew from 3787 to 25763 physicians; 65% of employed physicians provide primary care, while the majority of contracting physicians provide specialty care. Patient enrollment in HMOs grew from 285503 to 3028881. Annual capitation revenues grew from $190 million to $2.1 billion. Medical groups affiliated with PPMs are capitated for most professional, hospital, and ancillary clinical services and are increasingly delegated responsibility by HMOs for utilization management and quality assurance.Comment: Physician practice management organizations and their affiliated medical groups face the challenge of continuing rapid growth, sustaining stock values, and improving practice efficiencies while maintaining the loyalty of physicians and patients. [ABSTRACT FROM AUTHOR]

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