In vitro antimicrobial photodynamic therapy using tetra-cationic porphyrins against multidrug-resistant bacteria isolated from canine otitis.

Antimicrobial-resistant bacteria have been frequently isolated from canine otitis. Photodynamic therapy using porphyrins as photosensitizing molecules is an alternative therapy against microorganisms in localized infections. Therefore, we evaluated the antibacterial activity of two tetra-cationic porphyrins (H2TMeP and ZnTMeP) against gram-positive and -negative bacteria isolated from canine otitis, as well as its putative action mechanism. For this, two gram-positive and two gram-negative bacteria frequently detected in cases of canine otitis (coagulase-positive and -negative staphylococci [CPS and CNS], Pseudomonas aeruginosa, and Proteus mirabilis) were used in antibacterial activity assays. Each porphyrin at a non-cytotoxic dose was incubated with a fixed concentration of each bacterium and exposed to white-light irradiation for 0, 30, 60, and 90 min. Clinical isolates of CPS and CNS were photo-inactivated after 30 min of white-light exposure by both porphyrins (p < 0.05). Gram-negative bacteria were also photo-inactivated after 30 min (p < 0.05), reaching complete inactivation after 60 and 90 min of white-light irradiation by H2TMeP and ZnTMeP, respectively. Antibacterial assays using standard bacterial strains (ATCCs) demonstrated similar results to those obtained with clinical isolates, except for P. aeruginosa, which was completely inactivated by ZnTMeP at 60 min, and the absence of a significant reduction in P. mirabilis concentration when irradiated for 30 min. Similar assays were conducted using reactive oxygen species scavengers showing that the putative mechanism for bacterial inactivation is through the production of singlet oxygen species. These results indicated that H2TMeP and ZnTMeP tetra-cationic porphyrins were effective against bacteria isolated from canine otitis.

Goal setting for health behavior change: evidence from an obesity intervention for rural low-income women.

INTRODUCTION: Rural, minority populations are disproportionately affected by overweight and obesity and may benefit from lifestyle modification programs that are tailored to meet their unique needs. Obesity interventions commonly use goal setting as a behavior change strategy; however, few have investigated the specific contribution of goal setting to behavior change and/or identified the mechanisms by which goal setting may have an impact on behavior change. Furthermore, studies have not examined goal setting processes among racial/ethnic minorities. Using data from an obesity intervention for predominately minority women in rural North Carolina, this study sought to examine whether intervention participation resulted in working on goals and using goal setting strategies which in turn affected health behavior outcomes. It also examined racial/ethnic group differences in working on goals and use of goal setting strategies. METHODS: Data came from a community-based participatory research project to address obesity among low-income, predominately minority women in rural North Carolina. A quasi-experimental intervention design was used. Participants included 485 women aged 18 years and over. Intervention participants (n=208) received health information and goal setting support through group meetings and tailored newsletters. Comparison participants (n = 277) received newsletters on topics unrelated to obesity. Surveys assessed physical activity, fruit and vegetable intake, goal-related stage of change, and use of goal setting strategies. Chi squared statistics were used to assess intervention group differences in changes in goal-related stage of change and use of goal setting strategies as well as racial/ethnic group differences in stage of change and use of goal setting strategies at baseline. The causal steps approach of Baron and Kenny was used to assess mediation. RESULTS: Intervention compared to comparison participants were more likely to move from contemplation to action/maintenance for the goals of improving diet (58% intervention, 44% comparison, p= 0.04) and physical activity (56% intervention, 31% comparison, p ≤ 0.0001). Intervention group differences were not found for moving from precontemplation to a higher category. At baseline, black compared to white participants were more likely to be working on the goals of getting a better education (p < 0.0001), owning a home (p < 0.01), starting a business (p < 0.0001), and improving job skills (p <0.05). For whites only, intervention participants were more likely than comparison participants to move from contemplation to action/maintenance for the goal of improving diet ( p< 0.05). For both blacks (p < 0.05) and whites (p < 0.0001), intervention participants were more likely than comparison participants to move from contemplation to action/maintenance for the goal of increasing physical activity. For all participants, progression in stages of change mediated the intervention effect on physical activity, but not fruit and vegetable intake. The intervention did not reveal an impact on use of goal setting strategies. CONCLUSIONS: In this sample of low-income, rural women, the intervention's goal setting component influenced behavior change for participants who were contemplating lifestyle changes at baseline. Racial/ethnic group differences in goal setting indicate the need to gain greater understanding of individual, social, and environmental factors that may uniquely have an impact on goal setting, and the importance of tailoring obesity intervention strategies for optimal, sustainable behavior change.

Obesity, hope, and health: findings from the HOPE Works community survey.

According to hope theory, hope is defined as goal-directed thinking in which people perceive that they can find routes to desired goals and the motivation to use those routes. The purpose of this study was to explore relationships between hope and body mass index and hope and self-rated health among women completing a community survey conducted in four rural counties in eastern North Carolina. The survey was administered as part of Hope Works, a participatory, community-led intervention program to improve weight, health and hope among low-income women in rural North Carolina. Survey data from 434 women were analyzed. In multivariate models adjusting for age, race, education and income, higher hope was positively related to self-reported health (OR:0.92; 95% CI: 0.89-0.95) and negatively related to BMI (P < 0.01). These results indicated that women who reported better self-rated health also had higher hope scores and women who were heavier had lower hope scores. While these findings are exploratory, they suggest directions for further research. State-based hope is considered to be a characteristic that is malleable and open to development. Future interventions should examine the importance of hope as a construct to examine in weight loss studies. For example, programs could be designed to increase hope by focusing on goal setting and providing support, information and resources to help women work toward their goals.

The minimal important difference of exercise tests in severe COPD.

Our aim was to determine the minimal important difference (MID) for 6-min walk distance (6MWD) and maximal cycle exercise capacity (MCEC) in patients with severe chronic obstructive pulmonary disease (COPD). 1,218 patients enrolled in the National Emphysema Treatment Trial completed exercise tests before and after 4-6 weeks of pre-trial rehabilitation, and 6 months after randomisation to surgery or medical care. The St George's Respiratory Questionnaire (domain and total scores) and University of California San Diego Shortness of Breath Questionnaire (total score) served as anchors for anchor-based MID estimates. In order to calculate distribution-based estimates, we used the standard error of measurement, Cohen's effect size and the empirical rule effect size. Anchor-based estimates for the 6MWD were 18.9 m (95% CI 18.1-20.1 m), 24.2 m (95% CI 23.4-25.4 m), 24.6 m (95% CI 23.4-25.7 m) and 26.4 m (95% CI 25.4-27.4 m), which were similar to distribution-based MID estimates of 25.7, 26.8 and 30.6 m. For MCEC, anchor-based estimates for the MID were 2.2 W (95% CI 2.0-2.4 W), 3.2 W (95% CI 3.0-3.4 W), 3.2 W (95% CI 3.0-3.4 W) and 3.3 W (95% CI 3.0-3.5 W), while distribution-based estimates were 5.3 and 5.5 W. We suggest a MID of 26 ± 2 m for 6MWD and 4 ± 1 W for MCEC for patients with severe COPD.

Recombinant domains of mouse nidogen-1 and their binding to basement membrane proteins and monoclonal antibodies.

The basement membrane protein, nidogen-1, was previously shown to consist of three globular domains, G1 to G3, and two connecting segments. Nidogen-1 is a major mediator in the formation of ternary complexes with laminins, collagen IV, perlecan and fibulins. In the present study, we have produced recombinant proteins of these predicted domains in mammalian cells and used these proteins for crystallographic and binding epitope analyses. These fragments included G1, G2, the rod domain and a slightly larger G3 structure; all were obtained in good yields and were shown to be properly folded using electron microscopy. Surface plasmon resonance assays demonstrated high affinity binding (Kd = 3-9 nM) of domain G2 for collagen IV, perlecan domain IV-1 and fibulin-2, and a more moderate Kd for fibulin-1C. Domain G3 contained high affinity binding sites for the laminin gamma1 chain and collagen IV (Kd = 1 nM) and weaker binding sites for fibulin-1C and fibulin-2. A moderate binding affinity was also observed between domain G1 and fibulin-2, while no activity could be detected for the nidogen rod domain. Together, these data indicate the potential of nidogen-1 for multiple interactions within basement membranes. A similar binding repertoire was also identified for seven rat monoclonal antibodies that bound with Kd = 2-30 nM to either G1, G1-G2, G2, the rod domain or G3. Three of the antibodies showed strongly reduced binding to G2 and G3 after complex formation with either a perlecan domain or laminin-1.

Structural basis for the high-affinity interaction of nidogen-1 with immunoglobulin-like domain 3 of perlecan.

Nidogen and perlecan are large multifunctional basement membrane (BM) proteins conserved in all metazoa. Their high-affinity interaction, which is likely to contribute to BM assembly and function, is mediated by the central G2 domain in nidogen and the third immunoglobulin (IG)-like domain in perlecan, IG3. We have solved the crystal structure at 2.0 A resolution of the mouse nidogen-1 G2-perlecan IG3 complex. Perlecan IG3 belongs to the I-set of the IG superfamily and binds to the wall of the nidogen-1 G2 beta-barrel using beta-strands C, D and F. Nidogen-1 residues participating in the extensive interface are highly conserved, whereas the corresponding binding site on perlecan is more variable. We hypothesize that a second, as yet unidentified, activity of nidogen overlaps with perlecan binding and accounts for the unusually high degree of surface conservation in the G2 domain.

Crystal structure and mutational analysis of a perlecan-binding fragment of nidogen-1.

Nidogen, an invariant component of basement membranes, is a multifunctional protein that interacts with most other major basement membrane proteins. Here, we report the crystal structure of the mouse nidogen-1 G2 fragment, which contains binding sites for collagen IV and perlecan. The structure is composed of an EGF-like domain and an 11-stranded beta-barrel with a central helix. The beta-barrel domain has unexpected similarity to green fluorescent protein. A large surface patch on the beta-barrel is strikingly conserved in all metazoan nidogens. Site-directed mutagenesis demonstrates that the conserved residues are involved in perlecan binding.

Use of the endometrial pipelle in the diagnosis of early abnormal gestations.

OBJECTIVE: To determine the sensitivity and specificity of the endometrial pipelle (Unimar, Wilton, CT) in detecting intrauterine chorionic villi, as compared to standard suction dilation and curettage (D and C). DESIGN: Prospective clinical study. SETTING: U. S. Navy Hospital near Tokyo, Japan. Small community hospital. PATIENT(S): All patients presenting for the surgical management of an early abnormal gestation were enrolled prospectively. The patient's age, gravidy, parity, estimated gestational age (EGA), diagnosis, preoperative beta human chorionic gonadotropin (betahCG) level, and preoperative transvaginal ultrasound (TVUS) data were recorded. INTERVENTION(S): An endometrial biopsy was performed in the operating room prior to standard suction dilatation and curettage (D and C). MAIN OUTCOME MEASURE(S): The presence of chorionic villi in the endometrial biopsy and curettage specimens were recorded for each patient. RESULT(S): The sensitivity of the endometrial pipelle in detecting intrauterine chorionic villi was 63% and the specificity was 80%. CONCLUSION(S): In the diagnosis of an early abnormal gestation, particularly in excluding an ectopic pregnancy, it would be ideal to replace the more invasive D and C with the outpatient endometrial biopsy in detecting intrauterine chorionic villi. However, the limited sensitivity of the endometrial biopsy limits its application in this clinical scenario. Our results compare with two previous studies and add to the limited patient database on this topic.

Neisseria gonorrhoeae screening in pregnancy.

All patients undergoing prenatal care at the U.S Naval Hospital in Yokosuka, Japan, have a gonorrhea culture performed at their intake visit. The objective of this study was to determine the prevalence of Neisseria gonorrhoeae in this military population and to propose an effective antenatal screening strategy based on the data. A retrospective 10-month review of patient data was performed. In addition, the guidelines for antenatal N. gonorrhoeae screening by the American College of Obstetricians and Gynecologists, the Centers for Disease Control and Prevention, the U.S. Department of Health and Human Services, and the World Health Organization were reviewed. During the study period, none of the screened patients (N = 518) had a gonococcal infection. The screening program at this facility will be modified based on the low-risk nature of the pregnant population. Specifically, high-risk patients will be screened selectively in the third trimester.

Laboratory testing for preeclampsia: result trends and screening recommendations.

To better direct screening for preeclampsia, we describe the result trends of the laboratory tests used in the workup of preeclampsia at our institution. The clinical characteristics of patients with abnormal test results are further detailed. The objective of the study is to recommend a laboratory screening regimen for preeclampsia based on the data. All patients who delivered at National Naval Medical Center from February to July 1996 who had blood urea nitrogen, creatinine, aspartate aminotransferase, alanine aminotransferase, or uric acid determinations as part of a workup for preeclampsia were identified. Results are reported, and the clinical characteristics of patients with abnormal tests were obtained from the medical record. Abnormalities of uric acid and liver enzymes were few in our patient population (6% and 7%, respectively). The majority of patients with abnormal uric acid and liver function tests had the classic clinical symptoms of preeclampsia; therefore, the laboratory data added little to the clinical diagnosis. There was a high rate of renal test abnormalities, necessitating further investigation. We recommend omitting liver function and uric acid testing in the routine screening for preeclampsia. The high incidence of abnormal renal tests warrants continued use of this screening test and, more importantly, further investigation into the relationship between abnormal renal tests and disease course.

Characterizing "blue blobs". Immunohistochemical staining and ultrastructural study.

OBJECTIVE: To investigate the nature and origin of "blue blobs" (Bbs) in atrophic Pap smears in postmenopausal women and to study their clinical significance. STUDY DESIGN: A retrospective study of 412 atrophic Pap smears from postmenopausal women was done to detect the presence of Bbs. The smears from 24 cases showing Bbs were further studied to evaluate the nature of the Bbs with special stains, immunohistochemistry and electron microscopy. RESULTS: Bbs showed a heterogeneous morphology, with variable numbers and staining intensity. The diameter of Bbs was approximately equivalent to that of a parabasal/intermediate squamous cell. Special stains showed Bbs to be positive for periodic acid-Schiff and methyl green pyronin and negative for mucicarmine and calcium. Immunohistochemistry revealed Bbs to be positive for cytokeratin, epithelial membrane antigen and carcinoembryonic antigen and negative for vimentin and muscle-specific actin. Some Bbs had residual ghost nuclear shadows. Electron microscopy revealed cellular skeletons with residual tonofilaments enmeshed within a loose cytoskeleton matrix and nuclei with variable degrees of degeneration. CONCLUSION: Special stains, immunohistochemistry and electron microscopy indicated that Bbs represent parabasal/intermediate squamous cells exhibiting various degree of degeneration. In general, Bbs appear to be of no clinical significance except as a source of potential diagnostic error.

The spatial orientation of the essential amino acid residues arginine and aspartate within the alpha1beta1 integrin recognition site of collagen IV has been resolved using fluorescence resonance energy transfer.

The interaction of collagen IV with cells is mediated mainly by the integrin alpha1beta1. The recognition site has been located to a segment of the triple-helical domain 100 nm away from the N terminus of the collagen molecule. The three essential amino acid residues of the alpha1beta1 binding site, arginine alpha2(IV)461 and the two aspartate residues alpha1(IV)461, are all located on different chains. Since the spatial array of the three residues depends on the stagger of the chains within the triple helix, the stagger has been elucidated using fluorescence resonance energy transfer with phenylalanine alpha1(IV)473 and tryptophan alpha2(IV)479 as the fluorescent donor/acceptor pair. The distance R between phenylalanine and tryptophan was determined by analysis of the energy transfer efficiency, E, and the orientation factor, kappa(2). In parallel, distance R and orientation factor, kappa(2 )were also calculated from the coordinates of the triple helix. Comparison of the calculated and empirically determined values unequivocally showed the stagger to be alpha1'alpha1alpha2. This arrangement of the three alpha chains describes the conformation of the alpha1beta1 integrin recognition site, that is the distinct orientation of the side-chains of the essential residues aspartate and arginine in respect to the helix axis.

Forecasting patient outcomes in the management of hyperlipidemia.

BACKGROUND: To forecast adult patient outcomes in the management of hyperlipidemia using adult National Health and Examination Survey III (NHANES III) population statistics and National Cholesterol Education Program (NCEP) guidelines for goals of therapy. METHODS: Review of the hyperlipidemia drug therapy English-language medical literature with emphasis on randomized controlled trials of more than 6 weeks' duration published in the last 7 years, product package inserts, US Food and Drug Administration submission information, and NHANES III population statistics. Data were extracted from studies of lipid-lowering therapy to modify low-density lipoprotein (LDL) levels for primary and secondary prevention of coronary heart disease. The data that were evaluated included sample size, study design, therapeutic intervention, length of study, percentage change in LDL levels, and patient demographics. RESULTS: Cumulative frequency curves of the LDL distribution among the US adult population were constructed. The mean efficacy of drug therapy from qualified studies was used to extrapolate the percentage of the population expected to respond to the intervention and to forecast the patient outcome. CONCLUSIONS: A useful tool for clinicians was constructed to approximate the percentage of patients, based on risk stratification, who would reach NCEP target goal after a given pharmacotherapeutic intervention to decrease LDL levels.

Evidence of skeletal muscle metabolic reserve during whole body exercise in patients with chronic obstructive pulmonary disease.

When freed from central cardiorespiratory limitations, healthy human skeletal muscle has exhibited a significant metabolic reserve. We studied the existence of this reserve in 10 severely compromised (FEV1 = 0.97 +/- SE 0.01) patients with chronic obstructive pulmonary disease (COPD). To manipulate O2 supply and O2 demand in locomotor and respiratory muscles, subjects performed both maximal conventional two-legged cycle ergometry (large muscle mass) and single-leg knee extensor exercise (KE, small muscle mass) while breathing room air (RA), 100% O2, and 79% helium + 21% O2 (HeO2). With each gas mixture, peak ventilation, peak heart rate, and perceived breathlessness were lower in KE than cycle exercise (p < 0. 05). Arterial O2 saturation and maximal work capacity increased in both exercise modalities while subjects breathed 100% O2 (work: +10% bike, +25% KE, p < 0.05). HeO2 increased maximal work capacity on the cycle (+14%, p < 0.05) but had no effect on KE. HeO2 resulted in the greatest maximum minute ventilation in both bike and KE (p < 0. 05) but had no effect on arterial O2 saturation. Thus, a skeletal muscle metabolic reserve in these patients with COPD is evidenced by: (1) greater muscle mass specific work in KE; (2) greater work rates with higher fraction of inspired oxygen (FIO2); (3) an even greater effect of FIO2 during KE (i.e., when the lungs are less challenged); and (4) the positive effect of HeO2 on bicycle work rate. This skeletal muscle metabolic reserve suggests that reduced whole body exercise capacity in COPD is the result of central restraints rather than peripheral skeletal muscle dysfunction, while the beneficial effect of 100% O2 (with no change in maximum ventilation) suggests that the respiratory system is not the sole constraint to oxygen consumption.

Maximizing functional capacity. Pulmonary rehabilitation and adjunctive measures.

Pulmonary rehabilitation has become an important adjunct to standard medical therapy, with the primary goal of restoring patients to the highest possible functional state using a combination of exercise training, education, respiratory and chest physiotherapy techniques, and psychosocial support. Evidence supports the use of this combined modality therapy for motivated patients with disability from chronic lung disease. Although pulmonary function generally does not change, exercise tolerance can improve, together with decreased symptoms of breathlessness, improved quality of life, and less need for health care services. Patients are empowered with a better understanding of their disease and the proper usage of medications, oxygen therapy, and chest physiotherapy techniques. Thus, pulmonary rehabilitation enables patients to make the most of their lungs and their life.

A large outbreak of botulism: the hazardous baked potato.

In April 1994, the largest outbreak of botulism in the United States since 1978 occurred in El Paso, Texas. Thirty persons were affected; 4 required mechanical ventilation. All ate food from a Greek restaurant. The attack rate among persons who ate a potato-based dip was 86% (19/22) compared with 6% (11/176) among persons who did not eat the dip (relative risk [RR] = 13.8; 95% confidence interval [CI], 7.6-25.1). The attack rate among persons who ate an eggplant-based dip was 67% (6/9) compared with 13% (241189) among persons who did not (RR = 5.2; 95% CI, 2.9-9.5). Botulism toxin type A was detected from patients and in both dips. Toxin formation resulted from holding aluminum foil-wrapped baked potatoes at room temperature, apparently for several days, before they were used in the dips. Consumers should be informed of the potential hazards caused by holding foil-wrapped potatoes at ambient temperatures after cooking.

A nationwide case-control study of Escherichia coli O157:H7 infection in the United States.

Risk factors for Escherichia coli O157:H7 infection were investigated in a case-control study at 10 medical centers throughout the United States. Among 73 case-patients and 142 matched controls, exposures in the 7 days before illness associated with E. coli O157:H7 infection in univariate analysis included consumption of hamburger (matched odds ratio [MOR], 3.8; 95% confidence interval [CI], 1.9-7.9), undercooked hamburger (MOR, 4.5; 95% CI, 1.6-12.2), or hot dogs (MOR, 2.2; 95% CI, 1.1-4.4); eating at a fast-food restaurant (MOR, 2.3; 95% CI, 1.1-4.6); drinking unchlorinated well water (MOR, 2.4; 95% CI, 1.1-5.7); swimming in a pond (MOR, 5.4; 95% CI, 1.1-26.0); and having a household member with diarrhea (MOR, 11.9; 95% CI, 2.7-53.5). In multivariate analysis, only eating undercooked hamburger remained associated with infection. Seven (8%) of 93 patients developed hemolytic uremic syndrome and 1 died. Prevention strategies aimed at modifying risk factors may help to reduce the risk of infection with E. coli O157:H7.