Knee thrust prevalence and normative hip-knee-ankle angle deviation values among healthy individuals across the lifespan.

OBJECTIVE: To report the prevalence of varus thrust and normative values for hip-knee-ankle (HKA) angle deviation across the lifespan, and to explore associations between HKA angle deviation and selected clinical factors. DESIGN: This was a cross-sectional observational study of 572 participants from the 1000 Norms Project, aged 3-101 years and who self-reported as being healthy. Video recordings (2D) of frontal plane gait were reviewed by physiotherapists for presence of knee thrust and quantification of HKA angle deviation (the difference between HKA angle at initial contact and mid-stance). Age and sex-stratified normative HKA angle deviation values were presented as means and 95% confidence intervals (CIs). Correlations were calculated between HKA angle and clinical measures (age, sex, body mass index (BMI), alignment, knee and hip strength, Knee Injury and Osteoarthritis Outcomes Scores (KOOS), foot posture index, temporo-spatial gait, and hypermobility). RESULTS: Overall, 31% of the cohort had varus thrust, most prevalent among adults older than 60 years (42%) and children aged 3-9 (41%). Varus thrust was common in adolescents (25%) and adults aged 20-59 (23%). Mean HKA angle deviation for the entire cohort was 1.2° (95%CI: 1.07, 1.36) towards varus, and 2.1° (95%CI: 1.84, 2.36) among people with clinical varus thrust. Weak associations were identified between HKA angle deviation and BMI, stride width, and KOOS-Sports among adolescents, and in adults weakly associated with height. CONCLUSIONS: Prevalence of varus thrust is common across the lifespan. Normative values established here can be readily used by clinicians and researchers in monitoring this gait deviation.

Self-reported knee pain and disability among healthy individuals: reference data and factors associated with the Knee injury and Osteoarthritis Outcome Score (KOOS) and KOOS-Child.

OBJECTIVE: To develop normative reference data for the Knee injury and Osteoarthritis Outcome Score (KOOS) and KOOS-Child, as well as investigate socio-demographic, psychological and physical factors associated with knee pain and disability among healthy adults. METHOD: The KOOS or KOOS-Child (each containing five subscales) was administered to participants aged 8-101 years within the 1000 Norms Project, an observational study of 1000 self-reported healthy individuals. Self-efficacy, physical activity, body mass index (BMI), lower limb alignment, knee frontal plane projection angle (FPPA), knee range of motion (ROM), knee and hip strength, six-minute walk, 30-second chair stand and timed up and down stairs tests were collected. KOOS data were dichotomised using established cut-off scores and logistic regression analyses were conducted for each subscale. RESULTS: Socio-demographic characteristics were similar to the Australian population. Normative reference data were generated for children (8-17 years) and adults (18-101 years). Female adults were up to twice as likely to report knee pain, symptoms and sport/recreation (Sport/Rec) limitations compared to males (P < .05). Older age, lower self-efficacy, greater BMI, varus lower limb alignment, lower knee flexion ROM and lower hip external rotation (ER) strength were independently associated with knee pain and disability among adults. CONCLUSIONS: Age- and gender-stratified reference data for the KOOS and KOOS-Child have been developed to guide interpretation of results in practice and research for individuals with knee disorders. Psychological and physical factors are linked with self-reported knee pain/disability among adults, and longitudinal studies to investigate causation are required.

A survey of alcohol and other drug use behaviors and risk factors in health profession students.

This survey assessed the alcohol and other drug (AOD) use habits and risk factors of health profession students at a midwestern university health science center. The authors administered a 75-item survey to 1,707 students in selected classrooms: 984 students responded for a return rate of 57.6%. In 1990, they found, alcohol use among the health profession students in the past year was comparable to that of undergraduate college students nationally (86%), although significantly fewer health profession students drank heavily (27% had five or more drinks in the past 2 weeks, compared with 41% of college students). The percentage of health profession students who reported using tobacco or illicit drugs was lower than the percentage of undergraduate students who used these substances. At the time of the study, 16% of the respondents may have had a potential current alcohol problem and 3.5% a potential drug problem. Pharmacy students most often reported negative consequences from their AOD use. Peer pressure influenced the drinking decisions of 55% of the respondents; students in dentistry and pharmacy experienced the least support from peers for their decisions to abstain from drinking. Family histories of alcohol problems were reported by 38% of the respondents, and family histories of drug use by 14.8%. Male health profession students, when compared with the female professional students, drank more and experienced more consequences of their drinking or drug use and were also more influenced by peers.

Relatedness of tetracycline resistance plasmids among species of coagulase-negative staphylococci.

Four isolates of Staphylococcus aureus and 98 isolates of coagulase-negative staphylococci representing six species all obtained from endocervical cultures were examined for antimicrobial susceptibility and for the presence of plasmids. More than 80% of the isolates were susceptible to each of 12 antimicrobial agents tested, whereas only 33% were susceptible to penicillin G, 30% were susceptible to cadmium chloride, and 41% were susceptible to tetracycline. Although no species-related susceptibility or plasmid patterns were detected, 77 isolates contained at least one plasmid and 43 contained a plasmid similar in mass to a 2.7-megadalton tetracycline resistance plasmid previously reported in staphylococci. Association of tetracycline resistance with plasmids of this size in four species was determined from curing experiments. No plasmids homologous with the tetracycline resistance locus of the Escherichia coli plasmid pBR322 were found among 11 isolates examined by DNA hybridization. Homology with a 2.7-megadalton plasmids (pRC701) from an endocervical isolate of S. aureus, however, was apparent for 2.7-megadalton plasmids harbored by six isolates as well as with larger plasmids harbored by three isolates. Restriction analysis revealed that pRC701 shared structural identity with two plasmids of a similar mass from two species of coagulase-negative staphylococci as well as with a previously characterized tetracycline resistance plasmid originating in S. aureus.

Evaluation of a sustained-release theophylline tablet in young asthmatics.

A sustained-release theophylline (SRT) tablet was evaluated in 15 children with moderately severe asthma between the ages of 3 and 5 years (4.2 +/- 0.83 years). They received a mean daily dose of 20.4 mg/kg given q12h for 3 or more weeks with daily symptom scores and twice daily peak flow rates (PFR) measured. Serum theophylline levels (STL) were then obtained at 0, 1, 2, 4, 6, 8, 10, and 12 hr (eight children had 24-hr samples obtained), along with PFRs every 3 hr. The mean peak STL (x +/- SD) was 16.6 +/- 4.4 and the trough was 5.9 +/- 2.8, with a peak-trough difference of 10.6 +/- 3.9. The average time to peak level was 3.9 hr. The mean +/- SD clearance was 1.42 +/- 0.63 ml/kg per min and the apparent T1/2 was 5.11 +/- 1.34 hr. The average weekly morning PFR for the 3-week period ranged from 116.8 +/- 41.2 to 127.4 +/- 37.4 L/min, and the evening PFT ranged from 126.5 +/- 38.4 to 137.0 +/- 40.9 L/min. In conclusion, the SRT tablet is effective in treating many young asthmatics on a 12-hr dosage schedule. For some children who experience excessive peak-trough differences, an 8-hr dosage schedule may be indicated.

Percutaneous absorption of iodochlorhydroxyquin in humans.

Iodochlorhydroxyquin (I) is used in the treatment of diaper rash and other skin disorders, and is presumed to undergo little or no percutaneous absorption. The absorption of (I) from a 3% cream was studied in 5 normal male subjects after a single application of the cream for 12 h. Plasma levels of the drug were followed for 24 h after initial application while urinary excretion was measured for 54 h. (I) was extracted from plasma and urine and assayed by high-performance liquid chromatography. The drug in the range of 0.37-0.56 micrograms/ml was detected in plasma 2 h after application and persisted throughout the treatment period. The mean excretion rate after 12 h of application was 58.4 micrograms/h and the excretion rate was 8.8 micrograms/h at 42 h posttreatment. The elimination rate constant was calculated to be 0.15 h-1. Approximately 40% of the drug was absorbed over the 12-h application period. From the above results it is apparent that significant percutaneous absorption of (I) occurs.

Serum theophylline levels in young children receiving a sustained-release theophylline tablet.

This study indicates that a sustained-release tablet may be used in certain young children on an every-12-hr dosing schedule with acceptable serum theophylline fluctuation. Many young children are able to swallow the tablet and dosing increments are convenient.

Penicillin and tetracycline resistance plasmids in Staphylococcus epidermidis.

The genetic nature of penicillin (Pc) and tetracycline (Tc) resistance plasmids in Staphylococcus epidermidis were studied and compared with those in S. aureus. Of 10 S. epidermidis strains transduced for penicillin resistance, we could isolate Pc plasmids from only 3. One of these plasmids also encoded for cadmium resistance and another encoded for resistance to ethidium bromide, traits also associated with S. aureus Pc plasmids. Endonuclease fingerprinting of the Pc plasmids from the two species revealed extensive heterogeneity. Two S. epidermidis strains were also transduced for tetracycline resistance. Both harbored plasmids indistinguishable from S. aureus Tc plasmids as judged by endonuclease fingerprinting. These data suggest that genetic exchange between S. aureus and S. epidermidis occurs in vivo.

Nitrosoguanidine sequential mutagenesis mapping of Mycobacterium tuberculosis genes.

Nitrosoguanidine-induced mutations occur at higher frequencies at the replication region than at other nonreplicating regions of the chromosome. Cultures of Mycobacterium tuberculosis synchronized with phenylethanol were used to determine the order of replication for 10 genes controlling drug resistance. Use of M. tuberculosis provided a 10-h replication map with good resolution because of the slow rate of deoxyribonucleic acid replication. The direction of chromosome replication could not be determined, but this study indicated no pause between rounds of deoxyribonucleic acid replication in a rich medium.

Isolating specific auxotrophic mutants of Mycobacterium smegmatis by using vancomycin.

After inducing mutagenesis with nitrosoguanidine, we used vancomycin enrichment in isolating auxotrophic mutants of Mycobacterium smegmatis. Compared with cycloserine and penicillin G, which are also cell wall inhibitors, vancomycin, with 24 h of exposure, produced less cell lysis and a greater reduction in viable cell numbers. With vancomycin enrichment, 13 specific auxotrophs were isolated after nitrosoguanidine-induced mutation, whereas only two mutants were isolated without enrichment.

Oral syringe use survey.

Use of oral syringes at children's and ASHP-accredited residency hospitals in the United States was surveyed. Questionnaires were mailed to 131 hospitals; 117 (89.3%) were returned. Of the responding hospitals, 54.5% of children's hospitals and 67.1% of residency hospitals used oral syringes. There was no definite preference for a particular brand or type (glass vs. plastic) of syringe. Patients who often required liquid dosage forms, including pediatric and geriatric patients and patients with nasogastric tubes, were most frequently included in oral syringe distribution systems. Twenty-six of the 73 hospitals utilizing oral syringes used them for most unit dose liquids in all drug distribution systems. The remainder reported use for specific medications or circumstances. Expiration dating policies varied from 24 hours to one year to the manufacturer's expiration dating. The survey indicates widespread use of oral syringes and identifies a need for evaluation of medication stability in these devices.

Transduction of penicillinase production in Staphylococcus epidermidis and nature of the genetic determinant.

Four strains of Staphylococcus epidermidis from clinical sources were capable of serving as donors for the transduction of either penicillinase production, ethidium bromide resistance, or tetracycline resistance. Three typing phages served as transducing phages and, depending upon the combination of transducing phage, donor strain, and recipient strain, the rates of transduction ranged between 10(-5) and 10(-9). In one strain, cotransduction of penicillinase production and ethidium bromide resistance was observed. Although ultraviolet irradiation kinetics indicated that both the tetracycline resistance and the penicillin resistance determinants were located on plasmids, only resistance to tetracycline could be eliminated by growth in the presence of curing agents or at elevated temperature. However, evidence was obtained by agarose gel electrophoretic studies that both the tetracycline resistance and the penicillin resistance determinants are located on separate plasmids in this organism.

Stability of penicillin V potassium in unit dose oral syringes.

The stability of reconstituted penicillin V potassium (PVK) when stored in 6-ml plastic oral syringes at various temperatures and protected from light was studied. One batch of PVK was reconstituted with distilled water according to manufacturer's directions (label claim: 125 mg/ml). Samples of 5 ml were stored in plastic oral syringes at 4 C, 25 C, 41 C, 60 C or 75 C and assayed spectrophotometrically and microbiogically at various times. From an initial concentration of 113% of label claim, PVK stored at 4 C (refrigerated) reached 90% of manufacturer's label claim in 11.5 days (95% confidence level). PVK stored at 25 C (room temperature) was unstable after storage for less than 37 hours. PVK degradation followed a first-order process. No significant difference was found between the spectrophotometric and microbiological assay (p less than 0.05). Manufacturer's stability data for storage of reconstituted PVK in the original bulk container should not be applied to PVK repackaged in plastic oral syringes. The pharmacy department developed guideliness designed to prevent the administration of subpotent PVK.

Chromosomal map location of the methicillin resistance determinant in Staphylococcus aureus.

Three-factor genetic crosses performed by transformation have shown that the methicillin resistance determinant of Staphylococcus aureus strain DU4916 (the mec-4916 marker) is linked to a novobiocin resistance (Novr) marker (nov-142) and mutational sites affecting pyrimidine (pyr-141), purine (pur-102), and histidine (hisG15) biosynthesis in S. aureus strain 8325. The linkage group thus defined is pyr-141-hisG15-nov-142-pur-102-mec-4916. Phage 80alpha previously propagated on a novobiocin-resistant, methicillin-sensitive (Mecs) 8325 strain was used to infect 21 novobiocin-sensitive, methicillin-resistant clinical isolates (including strain DU4916). Among the novobiocin-resistant transductants so obtained from each recipient, between 1 and 5% were methicillin sensitive (reflecting cotransduction of Novr and Mecs). These results are consistent with the genetic determinant of methicillin resistance having a single chromosomal locus in most, if not all, strains of S. aureus.