Cancer, comorbidities, and health-related quality of life of older adults

This study examined the physical and mental health of 126,685 males and females age 65 or over, with and without cancer that completed a Medicare Health Outcomes Survey (MHOS) between 1998-2002. Cancer information was ascertained through the National Cancer Institute's (NCI's) Surveillance, Epidemiology and End Results (SEER) program and linked to MHOS data. Results indicated that across most cancer types, cancer patients reported significantly more comorbid conditions and poorer physical and mental health compared with patients without cancer. Negative associations were most pronounced in those with two or more comorbidities and in those diagnosed with cancer within the past year.

Standardizing patient-reported outcomes assessment in cancer clinical trials: a patient-reported outcomes measurement information system initiative

Patient-reported outcomes (PROs), such as symptom scales or more broad-based health-related quality-of-life measures, play an important role in oncology clinical trials. They frequently are used to help evaluate cancer treatments, as well as for supportive and palliative oncology care. To be most beneficial, these PROs must be relevant to patients and clinicians, valid, and easily understood and interpreted. The Patient-Reported Outcomes Measurement Information System (PROMIS) Network, part of the National Institutes of Health Roadmap Initiative, aims to improve appreciably how PROs are selected and assessed in clinical research, including clinical trials. PROMIS is establishing a publicly available resource of standardized, accurate, and efficient PRO measures of major self-reported health domains (eg, pain, fatigue, emotional distress, physical function, social function) that are relevant across chronic illnesses including cancer. PROMIS is also developing measures of self-reported health domains specifically targeted to cancer, such as sleep/wake function, sexual function, cognitive function, and the psychosocial impacts of the illness experience (ie, stress response and coping; shifts in self-concept, social interactions, and spirituality). We outline the qualitative and quantitative methods by which PROMIS measures are being developed and adapted for use in clinical oncology research. At the core of this activity is the formation and application of item banks using item response theory modeling. We also present our work in the fatigue domain, including a short-form measure, as a sample of PROMIS methodology and work to date. Plans for future validation and application of PROMIS measures are discussed.

Fatigue in breast cancer survivors two to five years post diagnosis: a HEAL Study report

PURPOSE

The purpose of this study was to estimate prevalence of fatigue, identify correlates of fatigue and evaluate the relationship between fatigue and health-related quality of life (HRQOL) in a large cohort of disease-free breast cancer survivors.

METHODS

Participants are enrolled in the HEAL Study, a multi-center prospective study of women diagnosed with in-situ to Stage IIIA breast cancer. HEAL participants (n = 1183) completed a baseline and a 24-month follow-up interview. Women in this report (n = 800) also completed a quality of life questionnaire that included the Piper Fatigue Scale and the RAND SF-36 two to five years after diagnosis. Multivariate regression methods were used to identify significant factors associated with fatigue. SF-36 scores for fatigued survivors were compared to non-fatigued survivor scores and population norms.

RESULTS

Forty-one percent of the breast cancer survivors were fatigued. Significant correlates of fatigue included pain, cognitive problems, physical inactivity, weight gain/personal appearance and antidepressant use. Fatigue was associated with poorer HRQOL, most notably in areas of role and social functioning.

CONCLUSION

This study provides further support for the conclusion that a significant proportion of breast cancer survivors experience fatigue that compromises HRQOL two to five years post-diagnosis.

Possible socioeconomic and ethnic disparities in quality of life in a cohort of breast cancer survivors

BACKGROUND

This paper describes the ethnic and socioeconomic correlates of functioning in a cohort of long-term nonrecurring breast cancer survivors.

METHODS

Participants (n = 804) in this study were women from the Health, Eating, Activity, and Lifestyle (HEAL) Study, a population-based, multicenter, multiethnic, prospective study of women newly diagnosed with in situ or Stages I to IIIA breast cancer. Measurements occurred at three timepoints following diagnosis. Outcomes included standardized measures of functioning (MOS SF-36).

RESULTS

Overall, these long-term survivors reported values on two physical function subscales of the SF-36 slightly lower than population norms. Black women reported statistically significantly lower physical functioning (PF) scores (P = 0.01), compared with White and Hispanic women, but higher mental health (MH) scores (P < 0.01) compared with White and Hispanic women. In the final adjusted model, race was significantly related to PF, with Black participants and participants in the "Other" ethnic category reporting poorer functioning compared to the White referent group (P < 0.01, 0.05). Not working outside the home, being retired or disabled and being unemployed (on leave, looking for work) were associated with poorer PF compared to currently working (both P < 0.01).

CONCLUSION

These data indicate that race/ethnicity influences psychosocial functioning in breast cancer survivors and can be used to identify need for targeted interventions to improve functioning.

Sensitivity of an immunomagnetic-separation-based test for detecting Escherichia coli O26 in bovine feces

The sensitivity of a test for cattle shedding Escherichia coli serogroup O26 was estimated using several fecal pats artificially inoculated at a range of concentrations with different E. coli O26 strains. The test involves the enrichment of fecal microflora in buffered peptone water, the selective concentration of E. coli O26 using antibody-coated immunomagnetic-separation beads, the identification of E. coli colonies on Chromocult tryptone bile X-glucuronide agar, and confirmation of the serogroup with E. coli serogroup O26-specific antisera using slide agglutination. The effective dose of E. coli O26 for an 80% test sensitivity (ED(80)) was 1.0 x 10(4) CFU g(-1) feces (95% confidence interval, 4.7 x 10(3) to 2.4 x 10(4)). Differences in test sensitivity between different E. coli O26 strains and fecal pats were also observed. Individual estimates of ED(80) for each strain and fecal pat combination ranged from 4.2 x 10(2) to 4.8 x 10(5) CFU g(-1). These results suggest that the test is useful for identifying individuals shedding a large number of E. coli O26 organisms or, if an appropriate number of individuals in a herd are sampled, for identifying affected herds. The study also provides a benchmark estimate of sensitivity that can be used to compare alternative tests for E. coli O26 and a methodological approach that can be applied to tests for other pathogenic members of the Enterobacteriaceae and other sample types.

Psychometric evaluation of the Brief Cancer Impact Assessment among breast cancer survivors

OBJECTIVES

The increasing number of cancer survivors brings greater attention to the biopsychosocial impact of surviving cancer. Instruments exist that measure quality of life (QOL), symptoms, and specific types of functioning after cancer; however, a reliable and valid assessment of the perceived impact of cancer (IOC) on the life plans and activities of cancer survivors has been missing. This study evaluated the psychometric properties of the 16-item Brief Cancer Impact Assessment (BCIA).

METHODS

Factor analysis with Promax oblique rotation established the factor structure of the BCIA in 783 ethnically diverse breast cancer survivors, >or=2 years after diagnosis. Construct validity was assessed by comparing factor-based scale means by demographic and treatment characteristics, and correlating scales with psychosocial and health-related QOL scales.

RESULTS

Factor analysis revealed four factors measuring the IOC on caregiving and finances, exercise and diet behaviors, social and emotional functioning, and religiosity. Scale scores differed by demographic and treatment characteristics according to expectations, and the pattern of correlations with psychosocial and health-related QOL generally supported the construct validity of the scales.

CONCLUSION

Including the BCIA with measures of QOL, symptoms, and functioning will allow researchers to gain a more comprehensive assessment of the biopsychosocial IOC in survivors.

Prevalence and virulence factors of Escherichia coli serogroups O26, O103, O111, and O145 shed by cattle in Scotland

A national survey was conducted to determine the prevalence of Escherichia coli O26, O103, O111, and O145 in feces of Scottish cattle. In total, 6,086 fecal pats from 338 farms were tested. The weighted mean percentages of farms on which shedding was detected were 23% for E. coli O26, 22% for E. coli O103, and 10% for E. coli O145. The weighted mean prevalences in fecal pats were 4.6% for E. coli O26, 2.7% for E. coli O103, and 0.7% for E. coli O145. No E. coli O111 was detected. Farms with cattle shedding E. coli serogroup O26, O103, or O145 were widely dispersed across Scotland and were identified most often in summer and autumn. However, on individual farms, fecal shedding of E. coli O26, O103, or O145 was frequently undetectable or the numbers of pats testing positive were small. For serogroup O26 or O103 there was clustering of positive pats within management groups, and the presence of an animal shedding one of these serogroups was a positive predictor for shedding by others, suggesting local transmission of infection. Carriage of vtx was rare in E. coli O103 and O145 isolates, but 49.0% of E. coli O26 isolates possessed vtx, invariably vtx1 alone or vtx1 and vtx2 together. The carriage of eae and ehxA genes was highly associated in all three serogroups. Among E. coli serogroup O26 isolates, 28.9% carried vtx, eae, and ehxA-a profile consistent with E. coli O26 strains known to cause human disease.

Stress and weight gain in parents of cancer patients

OBJECTIVE

To investigate the effects of chronic stress on weight changes and related behavioral changes in parents with a child who had just been diagnosed with cancer compared to parents with healthy children.

DESIGN

Longitudinal case-control study with assessments occurring over a three-month period following the child's diagnosis of cancer.

SUBJECTS

In total, 49 parents of healthy children and 49 parents of cancer patients aged 19-58.

MEASUREMENTS

Body weight, diet, physical activity, self-reported mood and stress.

RESULTS

Parents of cancer patients were more likely to gain weight, and experienced significantly greater weight gain over the 3 months than parents of healthy children. The magnitude of weight gain was related to the degree of psychological distress that the parents experienced. Parents of cancer patients reported lower levels of physical activity and lower caloric intake than parents of healthy children, with the most marked differences between groups occurring in the area of physical activity.

CONCLUSION

Findings suggest that a major stressor, such as a child's diagnosis of cancer, is associated with weight gain. Further research is needed to determine how long these weight gains persist and whether other types of stress also produce weight gains. Such studies should focus not only on the effect of stress on eating behavior but also on physical activity.

Gender differences in balance performance at the time of retirement

BACKGROUND

Impairments in balance performance are a commonly accepted risk factor for falling in older people. Since there is a higher reported incidence of falling in women, it is of interest to test whether this correlates with poorer balance performance in women than men at the time of retirement in order to plan health promotional strategies. The purpose of this study was to investigate whether any gender differences exist in balance performance in people approaching retirement age.

METHODS

Ninety-seven healthy volunteers (44 males, 53 females) planning to retire shortly were enrolled in the study (age range 50-67 years). Balance assessments during quiet standing were performed under various conditions; feet together eyes open, feet together eyes closed and single limb stance eyes open. The range of centre of pressure displacement in both the anterior-posterior and medial-lateral planes was collected for each task using a force platform.

FINDINGS

For several of the balance tasks the men exhibited a statistically significant larger range of centre of pressure displacement than the women (P<0.01). However, after normalising the data for height, no gender differences were seen. Over half of the group failed to complete all three single limb stance trials on both limbs.

INTERPRETATION

When the data was normalised for height, no differences were found in static balance performance between men and women of retirement age. A number of participants demonstrated balance impairments whilst performing the single limb stance likely to affect functional activities. Health promotional messages should be targeted equally at men and women.

Implications of high-molecular-weight oligomers of the binary toxin from Bacillus sphaericus

The mosquito-larvicidal binary toxin produced by Bacillus sphaericus is composed of BinB and BinA, which have calculated molecular weights of 51.4 and 41.9 kDa, respectively. NaOH extracts of B. sphaericus spores were analyzed using SDS-PAGE. Stained gels showed bands with molecular weights corresponding to those of BinB and BinA as well as two additional bands at 110 and 125 kDa. The matrix-assisted laser desorption/ionization mass spectrum of the purified 110 and 125 kDa bands showed two peaks at 104,160 and 87,358 Da that are assigned to dimers of BinB and BinA, respectively. Mass spectral analysis of trypsin-digested 110 and 125 kDa bands showed peaks at 51,328, 43,523, 43,130, and 40,832 Da that assigned to undigested BinB, two forms of digested BinB and digested BinA, respectively. Dynamic light scattering studies showed a solution of the purified 110 and 125 kDa bands was comprised almost entirely (99.6% of total mass) of a particle with a hydrodynamic radius of 5.6+/-1.2 nm and a calculated molecular weight of 186+/-38 kDa. These data demonstrate that the binary toxin extracted from B. sphaericus spores can exist in solution as an oligomer containing two copies each of BinB and BinA.

Distribution of Escherichia coli O157 in bovine fecal pats and its impact on estimates of the prevalence of fecal shedding

The distribution of Escherichia coli O157 in bovine feces was examined by testing multiple samples from fecal pats and determining the density of E. coli O157 in immunomagnetic separation (IMS)-positive fecal samples. The density of E. coli O157 in bovine feces was highly variable, differing by as much as 76,800 CFU g(-1) between samples from the same fecal pat. The density in most positive samples was <100 CFU g(-1), the limit of reliable detection by IMS. Testing only one 1-g sample of feces per pat with IMS may result in a sensitivity of detection as low as 20 to 50%. It is therefore probable that most surveys have greatly underestimated the prevalence of E. coli O157 shedding in cattle and the proportion of farms with shedding cattle. The sensitivity of the detection of E. coli O157 in bovine feces can be as much as doubled by testing two 1-g samples per pat rather than one 1-g sample.

Temporal shedding patterns and virulence factors of Escherichia coli serogroups O26, O103, O111, O145, and O157 in a cohort of beef calves and their dams

This study investigated the shedding of Escherichia coli O26, O103, O111, O145, and O157 in a cohort of beef calves from birth over a 5-month period and assessed the relationship between shedding in calves and shedding in their dams, the relationship between shedding and scouring in calves, and the effect of housing on shedding in calves. Fecal samples were tested by immunomagnetic separation and by PCR and DNA hybridization assays. E. coli O26 was shed by 94% of calves. Over 90% of E. coli O26 isolates carried the vtx(1), eae, and ehl genes, 6.5% carried vtx(1) and vtx(2), and one isolate carried vtx(2) only. Serogroup O26 isolates comprised seven pulsed-field gel electrophoresis (PFGE) patterns but were dominated by one pattern which represented 85.7% of isolates. E. coli O103 was shed by 51% of calves. Forty-eight percent of E. coli O103 isolates carried eae and ehl, 2% carried vtx(2), and none carried vtx(1). Serogroup O103 isolates comprised 10 PFGE patterns and were dominated by two patterns representing 62.5% of isolates. Shedding of E. coli O145 and O157 was rare. All serogroup O145 isolates carried eae, but none carried vtx(1) or vtx(2). All but one serogroup O157 isolate carried vtx(2), eae, and ehl. E. coli O111 was not detected. In most calves, the temporal pattern of E. coli O26 and O103 shedding was random. E. coli O26 was detected in three times as many samples as E. coli O103, and the rate at which calves began shedding E. coli O26 for the first time was five times greater than that for E. coli O103. For E. coli O26, O103, and O157, there was no association between shedding by calves and shedding by dams within 1 week of birth. For E. coli O26 and O103, there was no association between shedding and scouring, and there was no significant change in shedding following housing.

Detection of Escherichia coli serogroups O26, O103, O111 and O145 from bovine faeces using immunomagnetic separation and PCR/DNA probe techniques

AIMS

The aim of this study was to isolate Escherichia coli O26, O103, O111 and O145 from 745 samples of bovine faeces using (i) immunomagnetic separation (IMS) beads coated with antibodies to lipopolysaccharide, and slide agglutination (SA) tests and (ii) PCR and DNA probes for the detection of the Verocytotoxin (VT) genes.

METHODS AND RESULTS

IMS-SA tests detected 132 isolates of presumptive E. coli O26, 112 (85%) were confirmed as serogroup O26 and 102 had the VT genes. One hundred and twenty-two strains of presumptive E. coli O103 were isolated by IMS-SA, 45 (37%) were confirmed as serogroup O103 but only one of these strains was identified as Verocytotoxin-producing E. coli (VTEC). Using the PCR/DNA probe method, 40 strains of VTEC O26 and three strains of VTEC O103 were isolated. IMS-SA identified 21 strains of presumptive E. coli O145, of which only four (19%) were confirmed as serogroup O145. VTEC of this serogroup was not detected by either IMS-SA or PCR/DNA probes. E. coli O111 was not isolated by either method.

CONCLUSION

IMS beads were 2.5 times more sensitive than PCR/DNA probe methods for the detection of VTEC O26 in bovine faeces.

SIGNIFICANCE AND IMPACT OF THE STUDY

IMS-SA is a sensitive method for detecting specific E. coli serogroups. However, the specificity of this method would be enhanced by the introduction of selective media and the use of tube agglutination tests for confirmation of the preliminary SA results.

Applied technique for increasing calicivirus detection in shellfish extracts

AIMS

Optimal detection of enteric RNA viruses in clinical, environmental, and food products using reverse transcription-PCR (RT-PCR) when inhibitory substances in extracted sample materials are present.

METHODS AND RESULTS

We adapted a device for detection of RNA viruses in plant tissues and insects to detect a calicivirus strain (San Miguel sea lion virus, serotype 17) in water and oyster tissue extracts. This single, compartmentalized tube-within-a-tube (TWT) device for RT-PCR-nested PCR was compared to a conventional protocol of RT-PCR-nested PCR. In the presence of 100 mg of shellfish tissue extract equivalent, this TWT device decreases the calicivirus assay detection limit 10-fold over that of conventional RT-PCR-nested PCR while maintaining an identical detection limit of viral nucleic acid suspended in water. Both the conventional and TWT methods estimated the total particle-to-infectious particle ratio for this strain of calicivirus at approximately 40 : 1.

CONCLUSIONS

We believe that the TWT device with appropriate RT-PCR primers will decrease the detection limit for other calicivirus strains and RNA viruses in shellfish tissue extracts.

SIGNIFICANCE AND IMPACT OF THE STUDY

We believe that the TWT approach is applicable to other situations where RT and/or PCR inhibitory materials are present or nucleic acid targets of bacteria or viruses are at low levels in extracts of food products or clinical specimens.

Clinical measurement of muscle tone using a velocity-corrected modified Ashworth scale

OBJECTIVE

To develop a new form of the modified Ashworth scale (MAS) for muscle-tone assessment that combines the MAS score with the passive muscle-stretching velocity during the assessment of muscle tone, resulting in a measure that has higher intertester reliability than the MAS.

DESIGN

Twenty-two volunteer subjects with spinal cord injuries at a tertiary care outpatient and inpatient spinal cord injury rehabilitation center affiliated with a university were recruited for this study.

RESULTS

A decision tree in which V-MAS scores were obtained was developed. The data obtained from three independent raters, when adjusted by means of the V-MAS, showed an excellent interrater reliability.

CONCLUSIONS

Results indicated that the V-MAS is a more reliable measure. In addition, the resulting units of the V-MAS, ranging from 0 to 1, are of the same form as pendulum test data. The V-MAS method is quite simple to use because the rater need only measure the angular range and duration of the passive movement to calculate average velocity during the MAS assessment in addition to the normal MAS rating of muscle tone.

WHO activities for prevention of deafness and hearing impairment in children

This paper gives an overview of WHO activities in the global campaign for the prevention of deafness and hearing impairment, focusing particularly on children. It discusses the size of the problem and the causes and consequences of deafness and hearing impairment. It emphasizes the inadequate state of our knowledge of this subject in developing countries and the importance of collecting valid data. It describes the public health route to prevention of deafness and hearing impairment, especially through primary ear and hearing care, and outlines the World Health Organization's aims and activities for prevention of deafness and hearing impairment.

Management of radiated reoperative wounds of the cervicothoracic spine: the role of the trapezius turnover flap

Reoperation for malignant disease of the cervicothoracic spine can lead to compromised wound healing secondary to poor tissue quality from previous operations, heavily irradiated beds, and concomitant steroid therapy. Other complicating factors include exposed dura and spinal implants. Introducing well-vascularized soft tissue to obliterate dead space is critical to reliable wound healing. The purpose of this study was to determine the efficacy of the trapezius turnover flap in the management of these complex wounds. This study is a retrospective review of all patients undergoing trapezius muscle turnover flaps for closure of complex cervicothoracic wounds after spinal operations for metastatic or primary tumors. Six patients (3 male/3 female) were operated over an 18-month period (mean patient age, 43 years). Primary pathologies included radiation-induced peripheral nerve sheath tumor (N = 2), chondrosarcoma (N = 1), nonsmall-cell lung cancer (N = 1), paraganglioma (N = 1), and spindle cell sarcoma (N = 1). Trapezius muscle turnover flaps were unilateral and based on the transverse cervical artery in every patient. Indication for flap closure included inability to perform primary layered closure (N = 3), open wound with infection (N = 2), and exposed hardware (N = 1). All patients had previous operations of the cervicothoracic spine (mean, 5.8 months; range 2-9 months) for malignant disease and prior radiation therapy. Exposed dura was present in all patients, and 2 patients had dural repairs with bovine pericardial patches. Spinal stabilization hardware was present in 4 patients. All patients underwent perioperative treatment with systemic corticosteroids. All flaps survived, and primary wound healing was achieved in each patient. The only wound complication was a malignant pleural effusion communicating with the back wound, which was controlled with a closed suction drain. All wounds remained healed during the follow-up period. Four patients died from progression of disease within 10 months of surgery. The trapezius turnover flap has been used successfully when local tissue conditions prevent primary closure, or in the setting of open, infected wounds with exposed dura and hardware. The ease of flap elevation and minimal donor site morbidity make it a useful, single-stage reconstructive option in these difficult wounds.

Inhibition of Vesivirus infections in mammalian tissue culture with antisense morpholino oligomers

Caliciviruses infect and cause disease in animals and humans. They are nonenveloped, positive-stranded RNA viruses with a genome of approximately 7.5 kb that encodes viral proteins in three open reading frames (ORF). Antisense oligomers targeting one of the three ORF of caliciviruses of the genus Vesivirus significantly inhibit viral replication in tissue culture. Porcine kidney and African green monkey kidney cells were infected with Vesivirus isolates SMSV-13 and PCV Pan-1. Phosphorodiamidate morpholino oligomers (PMO) with sequence complementary to the AUG translation start site regions of ORF1, ORF2, and ORF3 were evaluated for their effect on viral titer. Scrape-loading delivered PMO to 50%-70% of the cells of the two cell lines, as measured by fluorescence microscopy and flow cytometry. A PMO targeting ORF3 caused a significant increase in viral titer. A PMO targeting ORF2, a scrambled PMO control sequence, and an unrelated PMO antisense sequence did not alter viral titer. Various PMO sequences antisense to an upstream region of ORF1 were effective in reducing viral titer up to 80% in a dose-dependent and sequence-specific manner. The extent of viral titer reduction was proportional to the delivery of PMO to cells. These observations demonstrate that antisense PMO can disrupt caliciviral gene function in a nucleic acid sequence-specific manner and are potentially effective antiviral agents.

Concentration and detection of caliciviruses in water samples by reverse transcription-PCR

Human caliciviruses (HuCVs) cause waterborne outbreaks of gastroenteritis. Standard indicators of a safe water supply do not adequately predict contamination of water by viruses, including HuCVs. We developed a method to concentrate and detect HuCVs in water samples by using a cultivable primate calicivirus (Pan-1) as a model. Viable Pan-1 was seeded in different types of water and then filtered with a 1MDS filter, eluted with beef extract (BE), and reconcentrated by polyethylene glycol (PEG) precipitation. The viruses in the final samples were tested by plaque assay or by reverse transcription (RT)-PCR following extraction of the RNA with Trizol. Pan-1 was more sensitive to high-pH treatment than poliovirus was; a pH 9.0 BE solution was found to recover 35% more viable Pan-1 than a pH 9.5 BE solution recovered. Pan-1 was recovered from small volumes of deionized, finished, ground, and surface waters at efficiencies of 94, 73, 67, and 64%, respectively, when samples were assayed after elution without further concentration. When larger volumes of water (up to 40 liters) were tested after elution and concentration with PEG, 38, 19, and 14% of the seeded Pan-1 were recovered from finished, ground, and surface waters, respectively. The limit of detection of Pan-1 by RT-PCR was estimated to be 0.75 to 1.5 PFU in 40 liters of finished water. This method may be adapted for monitoring HuCVs in drinking water and other types of water for public health safety.

Expression of the virulence-related Sca (Mn2+) permease in Streptococcus gordonii is regulated by a diphtheria toxin metallorepressor-like protein ScaR

The acquisition of transition metal ions by pathogenic bacteria is crucial to their growth and survival within the human host, however, the mechanisms of metal ion homeostasis in streptococci are unknown. The scaCBA operon in the human oral bacterium Streptococcus gordonii encodes the components of an ABC-type transporter for manganese (Mn2+). Production of substrate-binding lipoprotein ScaA was increased approximately fivefold in cells cultured in low Mn2+ medium (< 0.1 microM Mn2+), but not in iron (Fe2+/Fe3+)-limited medium, and was enhanced in the presence of human saliva or serum. mRNA analysis revealed that under low Mn2+ conditions, levels of scaCBA transcript (2.6 kb) were increased > 20-fold. The Mn2+-responsive transcriptional regulator of the sca operon was purified and characterized as a 215-amino-acid residue polypeptide, designated ScaR, with 26% identity to the Corynebacterium diphtheriae diphtheria toxin repressor (DtxR). Inactivation of scaR in S. gordonii DL1 (Challis) resulted in constitutive derepression of sca operon transcription. Expression of tpx, located immediately downstream of scaA and encoding a putative thiol peroxidase, was not subject to ScaR regulation. Purified ScaR protein bound to the scaC promoter region in vitro in the presence of Mn2+ (Kd approximately 80 nM) and, to a lesser extent, in the presence of Ni2+ or Zn2+. The metalloregulator protein binding region was localized by DNA protection analysis to a 46 bp sequence encompassing the -35 and -10 promoter signatures. This sequence was well conserved within the promoters of corresponding virulence-related permease operons in other streptococci. The results identify a new Mn2+-sensing regulator of Mn2+ transport in streptococci, important for Mn2+ homeostasis during infection of the human host.

Intrarater reliability of manual passive movement velocity in the clinical evaluation of knee extensor muscle tone

OBJECTIVE

To quantify the relationship between therapist-applied velocity of passive movement during a manual muscle test of muscle tone and the level of muscle tone represented by the relaxation index of the pendulum test.

DESIGN

Comparison of therapist-applied passive limb movement velocity during a manual muscle test with the same subject's level of muscle tone measured by the pendulum test. Three different therapists tested each subject. The relation between the velocity scores and pendulum test scores both intratherapist and intertherapist were assessed statistically by means of analysis of variance and correlation coefficients.

SETTING

A university-affiliated tertiary care outpatient and inpatient spinal cord injury rehabilitation center.

PARTICIPANTS

Twenty-two volunteer subjects with spinal cord injuries.

MAIN OUTCOME MEASURES

Passive knee angular displacement data were collected during both manual knee muscle testing and pendulum tests by using an electrogoniometer.

RESULTS

The therapists produced significantly different movement velocities during the manual muscle tests (p < .05). A significant correlation (p < .001) was found between pendulum test scores and passive velocities, indicating that in higher levels of muscle tone, the greater stretch reflex present provided greater resistance against the therapist force and subsequently decreased the velocity of the passive stretching.

CONCLUSIONS

Measurement of average velocity during passive stretching by itself can be used to evaluate muscle tone.

The use of pedicled expanded flaps for aesthetic resurfacing of the burned face

Reconstruction of extensive, deep burns of the face is a challenging problem in plastic surgery. The authors report the use of tissue expanders placed in the upper chest for facial resurfacing after burn injuries in 4 patients. The expanders are hyperinflated. The flap is then advanced upward to resurface an aesthetic unit of the face with the pedicle intact. The pedicle is divided 2 weeks later. The method of reconstruction allows a large area of facial resurfacing to be performed without fear of flap loss or flap retraction impairing the cosmetic result. This technique has the disadvantage of being a staged procedure and cannot be performed in those with burns of the upper chest.

Vortex flow and transverse flux screening at the bose glass transition

We study the vortex phase diagram in untwinned YBCO crystals with columnar defects. These randomly distributed defects are expected to induce a "Bose glass" phase of localized vortices exhibiting a vanishing resistance and Meissner effect for magnetic fields H( perpendicular) transverse to the columns. We directly observe the transverse Meissner effect using a Hall probe array. As predicted, the Meissner state breaks down at temperatures T(s) that decrease linearly as H( perpendicular) increases. However, T(s) lies far below the conventional melting temperature T(m) determined by a vanishing resistivity, suggesting a regime where vortices are effectively localized even when rotated off the columnar defects.

An atomic force microscopy investigation of bioadhesive polymer adsorption onto human buccal cells

Atomic force microscopy (AFM) was used to examine the buccal cell surface in order to image the presence of adsorbed bioadhesive polymers identified from previous work. Isotonic saline solution (5 ml) containing either polycarbophil (pH 7.6), chitosan (pH 4.5) or hydroxypropyl methylcellulose (pH 7.6) (0.5% w/v) was exposed to freshly collected buccal cells (ca. 48x10(4) cells/test) for 15 min at 30 degrees C. The cells were then rinsed with a small volume of double distilled water, allowed to air-dry on a freshy cleaved mica surface and imaged using contact mode AFM. Untreated cells showed relatively smooth surface characteristics, with many small 'crater-like' pits and indentations spread over cell surfaces. Cells that had been treated with all the investigated polymers appeared to have lost the crater and indentation characteristic and gained a higher surface roughness. These results suggest that polymer chains had adsorbed onto the cell surfaces. Quantitative image analysis of cell topography showed significant increases (P<0.05) in arithmetic roughness average (R(a)) for all the investigated polymer treated cells surfaces with respect to untreated control specimens. The changes in surface topography indicate the presence of adsorbed polymer, confirming previous work. This study demonstrates the suitability of AFM as a powerful and sensitive technique for detecting and imaging bioadhesive polymers present on mucosal cell surfaces.