Prevention of excessive exercise-induced adverse effects in rats with Bacillus subtilis BSB3

Aims

To characterize efficacy of the Bacillus subtilis BSB3 (BSB3) strain in the prevention of excessive exercise‐induced side effects and in maintaining stability of the gut microbiota.

Methods and Results

Rats were pretreated by oral gavage with B. subtilis BSB3 (BSB3) or with phosphate‐buffered saline (PBS) twice a day for 2 days, and were either exposed forced treadmill running or remained sedentary. Histological analysis of intestine, immunofluorescence staining of tight junction (TJ) proteins, serum lipopolysaccharide and intestinal fatty acid‐binding protein assay, culture‐based analysis and pyrosequencing for the gut microbiota were performed for each rat. Forced running resulted in a substantial decrease in intestinal villi height and total mucosa thickness, the depletion of Paneth cells, an inhibition of TJ proteins expression. Short‐term treatment of rats with BSB3 before running prevented these adverse effects. Culture‐based analysis of the gut microbiota revealed significant elevation of pathogenic microorganisms only in treadmill‐exercised rats pretreated with PBS. High‐throughput 16S rRNA gene sequencing also revealed an increase in pathobionts in this group. Preventive treatment of animals with BSB3 resulted in predominance of beneficial bacteria.

Conclusions

BSB3 prevents excessive exercise‐associated complications by beneficial modulation of the gut microbiota.

Significance and Impact of the Study

Our study shows a new application of beneficial bacteria for prevention the adverse effects of excessive exercise.

Testosterone and trenbolone enanthate increase mature myostatin protein expression despite increasing skeletal muscle hypertrophy and satellite cell number in rodent muscle

The androgen-induced alterations in adult rodent skeletal muscle fibre cross-sectional area (fCSA), satellite cell content and myostatin (Mstn) were examined in 10-month-old Fisher 344 rats (n = 41) assigned to Sham surgery, orchiectomy (ORX), ORX + testosterone (TEST; 7.0 mg week^-1 ) or ORX + trenbolone (TREN; 1.0 mg week^-1 ). After 29 days, animals were euthanised and the levator ani/bulbocavernosus (LABC) muscle complex was harvested for analyses. LABC muscle fCSA was 102% and 94% higher in ORX + TEST and ORX + TREN compared to ORX (p < .001). ORX + TEST and ORX + TREN increased satellite cell numbers by 181% and 178% compared to ORX, respectively (p < .01), with no differences between conditions for myonuclear number per muscle fibre (p = .948). Mstn protein was increased 159% and 169% in the ORX + TEST and ORX + TREN compared to ORX (p < .01). pan-SMAD2/3 protein was ~30-50% greater in ORX compared to SHAM (p = .006), ORX + TEST (p = .037) and ORX + TREN (p = .043), although there were no between-treatment effects regarding phosphorylated SMAD2/3. Mstn, ActrIIb and Mighty mRNAs were lower in ORX, ORX + TEST and ORX + TREN compared to SHAM (p < .05). Testosterone and trenbolone administration increased muscle fCSA and satellite cell number without increasing myonuclei number, and increased Mstn protein levels. Several genes and signalling proteins related to myostatin signalling were differentially regulated by ORX or androgen therapy.

Effects of testosterone treatment on markers of skeletal muscle ribosome biogenesis

The effects of testosterone (TEST) treatment on markers of skeletal muscle ribosome biogenesis in vitro and in vivo were examined. C₂ C₁₂ myotubes were treated with 100 nm TEST for short-term (24-h) and longer-term (96-h) treatments. Moreover, male 10-month-old Fischer 344 rats were housed for 4 weeks, and the following groups were included in this study: (i) Sham-operated (Sham) rats, (ii) orchiectomised rats (ORX) and (iii) ORX+TEST-treated rats (7.0 mg week^-1 ). For in vitro data, TEST treatment increased c-Myc mRNA expression by 38% (P = 0.004) after 96 h, but did not affect total RNA, 47S pre-rRNA, Raptor mRNA, Nop56 mRNA, Bop1 mRNA, Ncl mRNA at 24 h or 96 h following the treatment. For in vivo data, ORX decreased levator ani/bulbocavernosus (LABC) myofibril protein versus Sham (P = 0.006), whereas ORX+TEST (P = 0.015) rescued this atrophic effect. ORX also decreased muscle ribosome content (total RNA) compared to Sham (P = 0.046), whereas ORX+TEST tended to rescue this effect (P = 0.057). However, other markers of ribosome biogenesis including c-Myc mRNA, Nop56 mRNA, Bop1 mRNA, Ncl mRNA decreased with ORX independently of TEST treatments (P < 0.05). Finally, lower phospho-(Ser235/236)-to-total rps6 protein and lower rpl5 protein levels existed in ORX+TEST rats versus other treatments, suggesting that chronic TEST treatment may lower translational capacity.

A single 60-min bout of peristaltic pulse external pneumatic compression transiently upregulates phosphorylated ribosomal protein s6

We investigated whether a single 60-min bout of whole leg, peristaltic pulse external pneumatic compression (EPC) altered select growth factor-related mRNAs and/or various phospho(p)-proteins related to cell growth, proliferation, inflammation and apoptosis signalling (e.g. Akt-mTOR, Jak-Stat). Ten participants (8 males, 2 females; aged 22·2 ± 0·4 years) reported to the laboratory 4 h post-prandial, and vastus lateralis muscle biopsies were obtained prior to (PRE), 1 h and 4 h post-EPC treatment. mRNA expression was analysed using real-time RT-PCR and phosphophorylated and cleaved proteins were analysed using an antibody array. No changes in selected growth factor-related mRNAs were observed following EPC. All p-proteins significantly altered by EPC decreased, except for p-rps6 (Ser235/236) which increased 31% 1 h post-EPC compared to PRE levels (P = 0·016). Notable decreases also included p-BAD (Ser112; -28%, P = 0·004) at 4 h post-EPC compared to PRE levels. In summary, an acute bout of EPC transiently upregulates p-rps6 as well as affecting other markers in the Akt-mTOR signalling cascade. Future research should characterize whether chronic EPC application promotes alterations in lower-limb musculature and/or enhances exercise-induced training adaptations.

The stability of metabolic syndrome in children and adolescents

CONTEXT

Some studies suggest the presence of metabolic syndrome before adulthood may identify those at high risk for later cardiovascular morbidity, but there are few data examining the reliability of pediatric metabolic syndrome.

OBJECTIVE

To examine the short- and long-term stability of pediatric metabolic syndrome.

DESIGN

Metabolic syndrome was defined as having at least three of the following: waist circumference, blood pressure, and fasting serum triglycerides in the 90th or higher percentile for age/sex; high-density lipoprotein-cholesterol 10th or lower percentile for age/sex; and fasting serum glucose of at least 100 mg/dl. Short-term metabolic syndrome stability (repeated measurements within 60 d) was assessed in obese youth ages 6-17 yr. Long-term metabolic syndrome stability (repeated measurements more than 1.5 yr apart) was studied in 146 obese and nonobese children age 6-12 yr at baseline.

PATIENTS AND SETTING

Convenience samples of obese and nonobese youth ages 6-17 yr participating in research studies were collected at a clinical research hospital.

RESULTS

Short-term metabolic syndrome stability (repeat measurements performed 19.7 +/- 13.1 d apart) was assessed in 220 children. The diagnosis of metabolic syndrome was unstable in 31.6% of cases. At their short-term follow-up visit, incidence of metabolic syndrome among participants who did not have metabolic syndrome at baseline was 24%. In the long term (repeat measurements performed 5.6 +/- 1.9 yr apart), the diagnosis of metabolic syndrome was unstable in 45.5% of cases.

CONCLUSIONS

Cutoff-point-based definitions for pediatric metabolic syndrome have substantial instability in the short and long term. The value of making a cutoff-point-based diagnosis of metabolic syndrome during childhood or adolescence remains in question.

Local bone formation due to combined mechanical loading and intermittent hPTH-(1-34) treatment and its correlation to mechanical signal distributions

We evaluated the local response of cortical bone in the rat tibia due to combined treatment with synthetic parathyroid hormone, hPTH-(1-34), and mechanical stimulation by four-point bending. Forty-eight female retired breeder Sprague-Dawley rats were divided into six groups. Mechanically stimulated animals included the following groups: (1) Bend+PTH, (2) Sham+PTH, (3) Bend+Vehicle, (4) Sham+Vehicle. Non-mechanically stimulated animals included a (5) Control group that received neither loading nor injections, and a (6) PTH group that received only hPTH-(1-34) injections. The right limbs of mechanically loaded animals were exposed to a peak force of 50 N for 36 cycles at 2 Hz, three days per week for four weeks, and PTH-treated animals received injections equivalent to 50 microg/kg BW. Fluorochrome labeling was used to measure local formation at 12 sectors about the endocortical periphery. The distributions of endocortical bone formation were compared to the local formation differences between treatment groups and to a variety of potential mechanical stimuli signals. Results indicated that hPTH-(1-34) exerted a potent anabolic effect with near-uniform formation about the endocortical surface, and that localized formation peaks due to bending were further augmented in the presence of hPTH-(1-34) treatment. Correlation of formation patterns to mechanical signal distributions highlighted several candidate signals including the mid-principal stress, the dilatational strain, and the radial gradient of the local radial strain.

Prediction of maximal oxygen uptake by bioelectrical impedance analysis in overweight adolescents

AIM

Maximal oxygen uptake (VO(2max)), the gold standard for measurement of cardiorespiratory fitness, is frequently difficult to assess in overweight individuals due to physical limitations. Reactance and resistance measures obtained from bioelectrical impedance analysis (BIA) have been suggested as easily obtainable predictors of cardiorespiratory fitness, but the accuracy with which ht(2)/Z can predict VO(2max) has not previously been examined in overweight adolescents.

METHODS

The impedance index was used as a predictor of VO(2max) in 87 overweight girls and 47 overweight boys ages 12 to 17 with mean BMI of 38.6 + or - 7.3 and 42.5 + or - 8.2 in girls and boys respectively. The Bland Altman procedure assessed agreement between predicted and actual VO(2max).

RESULTS

Predicted VO(2max) was significantly correlated with measured VO(2max) (r(2)=0.48, P<0.0001). Using the Bland Altman procedure, there was significant magnitude bias (r(2)=0.10; P<0.002). The limits of agreement for predicted relative to actual VO(2max) were -589 to 574 mL O(2)/min.

CONCLUSIONS

The impedance index was highly correlated with VO(2max) in overweight adolescents. However, using BIA data to predict maximal oxygen uptake over-predicted VO(2max) at low levels of oxygen consumption and under-predicted VO(2max) at high levels of oxygen consumption. This magnitude bias, along with the large limits of agreement of BIA-derived predicted VO(2max), limit its usefulness in the clinical setting for overweight adolescents.

Insulin resistance, hyperinsulinemia, and energy intake in overweight children

OBJECTIVE

To examine the relationship between energy intake during a buffet meal and indexes of insulin dynamics in overweight children.

STUDY DESIGN

Ninety-five nondiabetic, overweight (body mass index > or = 95th percentile) children (age 10.3 +/- 1.4 years) selected lunch from a 9835-kcal buffet eaten ad libitum after an overnight fast. The associations between energy intake and measures of insulin dynamics, in the postabsorptive state and during a 2-hour hyperglycemic clamp, were determined. Covariates in the statistical model included race, sex, skeletal age, fat-free mass, fat mass, socioeconomic status, and number of foods in the buffet rated as acceptable.

RESULTS

Energy intake was positively associated with the fasting homeostasis model assessment for insulin resistance index (beta = 0.24, P = .042), fasting insulin/glucose ratio (beta = 0.24, P = .044), first-phase insulin (beta = 0.23, P = .032), and first-phase C-peptide (beta = 0.21, P = .046); energy intake was negatively associated with clamp-derived insulin sensitivity (beta = -0.29, P = .042). Each 10% decrease in clamp-derived insulin sensitivity predicted a 27-kcal greater energy intake.

CONCLUSIONS

Insulin resistance and hyperinsulinemia are associated with greater energy intake after an overnight fast in overweight children. These associations suggest mechanisms whereby insulin resistance may contribute to excessive weight gain in children.

Oxygen-uptake efficiency slope as a determinant of fitness in overweight adolescents

PURPOSE

Peak oxygen uptake (VO2peak) is frequently difficult to assess in overweight individuals; therefore, submaximal measures that predict VO2peak are proposed as substitutes. Oxygen uptake efficiency slope (OUES) has been suggested as a submaximal measurement of cardiorespiratory fitness that is independent of exercise intensity. There are few data examining its value as a predictor of V O2peak in severely overweight adolescents.

METHODS

One hundred seven severely overweight (BMI Z 2.50 +/- 0.34) and 43 nonoverweight (BMI Z 0.13 +/- 0.84) adolescents, performed a maximal cycle ergometer test with respiratory gas-exchange measurements. OUES was calculated through three exercise intensities: lactate inflection point (OUES LI), 150% of lactate inflection point (OUES 150), and VO2peak (OUES PEAK).

RESULTS

When adjusted for lean body mass, VO2peak and OUES at all exercise intensities were lower in overweight subjects (VO2peak: 35.3 +/- 6.4 vs 46.8 +/- 7.9 mL.kg(-1) LBM.min(-1), P < 0.001; OUES LI: 37.9 +/- 10.0 vs 43.7 +/- 9.2 mL.kg(-1) LBM.min(-1).logL(-1) P < 0.001; OUES 150: 41.6 +/- 9.0 vs 49.8 +/- 11.1 mL.kg(-1) LBM.min(-1).logL(-1) P < 0.001; and OUES PEAK: 45.1 +/- 8.7 vs 52.8 +/- 9.6 mL.kg(-1) LBM.min(-1).logL(-1) P < 0.001). There was a significant increase in OUES with increasing exercise intensity in both groups (P < 0.001). OUES at all exercise intensities was a significant predictor of VO2peak for both groups (r2 = 0.35-0.83, P < 0.0001). However, limits of agreement for predicted VO2peak relative to actual VO2peak were wide (+/- 478 to +/- 670 mL.min(-1)).

CONCLUSIONS

OUES differs significantly in overweight and nonoverweight adolescents. The wide interindividual variation and the exercise intensity dependence of OUES preclude its use in clinical practice as a predictor of VO2peak.

Influence of serum leptin on weight and body fat growth in children at high risk for adult obesity

OBJECTIVE

Our objective was to examine serum leptin prospectively as a predictor of weight and body fat growth in children at high risk for adult obesity. We hypothesized that leptin measurements would be positively associated with increased growth of adipose tissue because children with high baseline leptin for their body fat mass have greater leptin resistance and thus would have greater susceptibility to weight gain.

METHODS

Children ages 6-12 yr at high risk for adult obesity because of early-onset childhood overweight and/or parental overweight were recruited from 1996-2004. Growth in body mass index (BMI) was studied in 197 children, and growth in total body fat mass was examined in 149 children over an average follow-up interval of 4.4 yr (range, 1-8 yr). Longitudinal analyses accounted for sex, race, socioeconomic status, initial body composition, age, skeletal age, and physical activity and included all available interim visits for each individual so that a total of 982 subject visits were included in the analysis.

RESULTS

At baseline, 43% of children studied were overweight (BMI > or = 95th percentile); during follow-up, an additional 14% became overweight. Independent of initial body composition, baseline leptin was a statistically significant positive predictor of increased BMI (P = 0.0147) and increased total body fat mass (P < 0.007).

CONCLUSIONS

High serum leptin, independent of body fat, may be an indicator of increased leptin resistance, which predisposes children at high risk for adult obesity to somewhat greater growth in weight and body fat during childhood.

Differences between the perceived and actual age of overweight onset in children and adolescents

OBJECTIVE

Little is known about whether children or their parents can accurately recall the age at which they became overweight. DESIGN, SUBJECTS AND MAIN OUTCOME MEASURES: We interviewed 64 overweight children (7-18 years old) about their weight history and compared reported age of overweight onset with actual onset, as determined by the age at which the child's measured BMI first exceeded the 95th percentile.

RESULTS

Only 28% of children reported overweight onset within 1 year of actual overweight onset. Reported overweight onset age (7.6 +/- 2.5 y) and actual onset age (5.3 +/- 2.5 y; P < .001) were not significantly correlated (r2 = .03, P = .22). Children who became overweight before 8 years of age tended to report becoming overweight at a later age than actual onset, whereas children who became overweight after 8 years of age tended to report becoming overweight at an earlier age than actual onset (P < .001), with 27% of children either underreporting or overreporting their overweight onset by at least 5 years. Similar results were found when analyzing parent reports of their children's overweight onset.

CONCLUSIONS

Reported and actual overweight onset ages were uncorrelated in our sample, suggesting that families may not be cognizant of children's growth trajectories. Greater efforts should be made to help parents and children understand and track growth patterns with the aim of preventing excessive weight gain.

Shape adaptation of long bone structures using a contour based approach

In this work, an approach for mechanically driven shape adaptation of long bone structures is presented which utilizes contour descriptions to track morphological changes at different bone cross sections. A script-based procedure is used to iteratively generate a solid geometry and finite element (FE) model from these contours, perform a stress analysis, and then update the contour shapes using the results of the stress analysis using a prescribed remodeling rule. Because a remeshing operation is performed at each timestep the method is able to effectively simulate large changes in geometry. Several examples of shape adaptation of idealized and geometrically accurate long-bone structures are presented using a variety of remodeling signals and parameters.

The genome and proteome of coliphage T1

The genome of enterobacterial phage T1 has been sequenced, revealing that its 50.7-kb terminally redundant, circularly permuted sequence contains 48,836 bp of nonredundant nucleotides. Seventy-seven open reading frames (ORFs) were identified, with a high percentage of small genes located at the termini of the genomes displaying no homology to existing phage or prophage proteins. Of the genes showing homologs (47%), we identified those involved in host DNA degradation (three endonucleases) and T1 replication (DNA helicase, primase, and single-stranded DNA-binding proteins) and recombination (RecE and Erf homologs). While the tail genes showed homology to those from temperate coliphage N15, the capsid biosynthetic genes were unique. Phage proteins were resolved by 2D gel electrophoresis, and mass spectrometry was used to identify several of the spots including the major head, portal, and tail proteins, thus verifying the annotation.

Modem transmission of glucose values reduces the costs and need for clinic visits

OBJECTIVE

To determine whether modem technology allows for effective management of type 1 diabetes when used in lieu of a clinic visit.

RESEARCH DESIGN AND METHODS

A total of 70 adolescent patients with diabetes were prospectively randomized to either a control group or a modem group. Control group patients continued the standard of care of quarterly clinic visits, and modem group patients were instructed to transmit blood glucose data every 2 weeks for 6 months instead of a usual quarterly clinic visit. Health care providers analyzed the data received by modem and contacted patients to discuss diabetes treatment changes. GHbA(1c) levels were determined at 0 and 6 months, and the number of high and low blood glucose levels and adverse events were tracked. Clinic visit costs, patient expenses, and health care provider times were tracked for cost analysis for both groups.

RESULTS

A total of 63 patients (33 control, 30 modem) completed the 6-month study. The GHbA(1c) values significantly decreased in both groups, with no statistically significant difference between groups (P = 0.96). The occurrence of mild-to-moderate hypoglycemic events were similar in the two groups, and there were no severe hypoglycemic events. The average cost of care for a clinic visit was $305.00, whereas the cost for 6 months of modem transmission was $163.00.

CONCLUSIONS

This study shows that electronic transmission of blood glucose levels and other diabetes data every 2 weeks-in lieu of a clinic visit-results in a similar level of glucose control and incidence of acute diabetes complications when compared with current standard care.

Use of the GlucoWatch biographer in children with type 1 diabetes

OBJECTIVE

To determine whether use of the GlucoWatch biographer improves glucose control in children and adolescents with type 1 diabetes.

METHODS

Forty children in poor glucose control (glycohemoglobin [HbA1c] >8%) were randomized to diabetes management with or without glucose monitoring using the biographer. Conventional glucose monitoring was performed 4 times daily in both groups. Those randomized to the biographer group were asked to wear the device 4 times per week for 3 months (intervention phase) and to perform blood glucose monitoring if the biographer alerted them that glucose was < or =70 mg/dL (3.9 mmol/L) or > or =300 mg/dL (16.7 mmol/L). After 3 months, all patients received biographers and were followed for 6 months (observation phase). HbA1c values were determined at baseline and after 1, 3, 6, and 9 months.

RESULTS

The median HbA1c was 8.6% and 8.9% (control versus biographer) at baseline and was significantly lower in the biographer group after 3 months (8.4% vs 9%). More hypoglycemia was detected when subjects were wearing the biographer, especially at night. No severe hypoglycemia occurred. During the observation phase, HbA1c values at 6 months were 8.5% and 8.3% and at 9 months were 8.6% and 8.4% in the control and biographer groups, respectively. Two children dropped out of the study, 1 because of skin irritation from using the device.

CONCLUSIONS

The GlucoWatch biographer was well tolerated by children and adolescents and significantly improved glucose control compared with standard therapy. The use of the biographer with an alarm to detect nocturnal hypoglycemia has the potential to increase the safety of diabetes management in children.

Diabetic ketoacidosis with intracerebral complications

PURPOSE

To describe 11 instances of severe diabetic ketoacidosis (DKA) with secondary intracerebral complications (ICCs), nine of whom were treated early and showed complete recovery.

METHODS

Three hundred and eighty-one episodes of DKA were treated at Denver Children's Hospital (DCH) from January 1989 to December 1999. Nine instances of DKA with ICC were prospectively identified during this time period. Two additional occurrences were identified via a medical records search (total incidence, 2.9%). The signs, symptoms and laboratory values which led to their diagnosis and treatment are identified.

RESULTS

All nine children who received early treatment with i.v. mannitol showed complete recovery. An additional patient had central nervous system involvement upon arrival at our hospital and showed almost complete recovery. Another patient suffered a cardiorespiratory arrest before transfer to our hospital and died without being treated for cerebral edema.

CONCLUSION

Prevention of ICCs by the earlier diagnosis of diabetes and by being aware of possible risk factors for cerebral edema is the eventual goal. Based on our experience, mannitol should be given promptly for the treatment of ICCs indicated by the clinical course even if cerebral edema is not documented by a computed tomography (CT) scan.

The seven elements of RFP evaluation: is an RFP a solution or an added problem?

Administrators often receive requests for proposals (RFP), alerting them of the availability of funding. Applying for such funded service programs may or may not be beneficial to the agency the administrator leads. This article suggests a series of seven evaluation procedures for use in determining the potential outcome of securing the proposed program. It is recommended that this evaluation process be considered before the administrator responds to an RFP.

A critical analysis of cerebral computed tomography scanning before elective carotid endarterectomy and its correlation to carotid stenosis

BACKGROUND

Cerebral computed tomography (CT) scanning has been suggested to play a role in the management of patients before carotid endarterectomy (CEA). This prospective study analyzes the value of CT scanning before elective CEA and the correlation of CT findings to significant carotid stenosis.

METHODS

This study includes 131 consecutive patients considered for CEA during a 2-year period. All patients underwent carotid duplex ultrasonography, carotid arteriography, and CT scanning.

RESULTS

Eighty patients (61%) had transient ischemic attacks or prior strokes, and 51 (39%) had nonhemispheric symptoms or were asymptomatic. The CT scan was abnormal in 36 (27%) patients; however, no brain tumors or abnormalities to affect clinical management were revealed. Ninety-two CEAs were performed on 87 patients. Twenty-nine (32%) in the operative group had abnormal CT scans, but these did not influence operative decisions. On the basis of this rate of 0% of patients with CT findings to change surgical management in 92 cases, a maximum true rate of occurrence of up to 5% could be detected with alpha equals 0.05 by sampling a population of this size. Four patients (4%) had postoperative cerebral vascular accidents, and all of these had normal preoperative scans. Patients with 50% or more carotid stenosis on arteriogram were significantly more likely to have abnormal CT scans than patients with less than 50% stenosis (20% versus 7%, p = 0.0034). As carotid stenosis became more significant, the frequency of abnormal CT scans increased (p < 0.01). The cost of CT scanning was $66,089.50 in this study.

CONCLUSIONS

Significant carotid stenosis was associated with a higher frequency of abnormal CT scans; however, routine preoperative CT scanning was unnecessary before elective CEA.

Purification and characterization of alpha-toxin produced by Clostridium novyi type A

Our study describes the production, purification, and properties of alpha-toxin from Clostridium novyi type A 19402. The bacterium produced maximal amounts of alpha-toxin when grown at 37 degrees C for 72 h in dialysis flask cultures containing brain heart infusion supplemented with 0.75% Tween 80 and 2% glycerol. The alpha-toxin was purified by precipitation with polyethylene glycol 6000, followed by chromatography on Q-Sepharose, phenyl-agarose, and Mono-Q. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the toxin exhibited a single band with an M(r) of 200,000. The toxin also exhibited a single immunoprecipitin arc by crossed immunoelectrophoresis with antiserum against crude toxin. It was stable when stored at 4 degrees C and also following exposure to buffers with pHs in the range of 4 to 7. The toxin had a minimum lethal dose in mice of 5 to 10 ng, caused rounding of a variety of cells in tissue culture, and was negative in the rabbit ileal loop assay. The cytotoxic activity was inhibited by agents that affect receptor-mediated processes, and the toxin was less active on a CHO mutant cell line that is defective in endosomal acidification. The analysis of the amino acid composition revealed an unusually high proline content. The N-terminal sequence is Met-Leu-Ile-Thr-Arg-Glu-Gln-Leu-Met-Lys.

Methylphenidate in stroke patients with depression

The treatment of depression after stroke is a difficult clinical problem. Many of the medications used to treat patients with depression in the general population have significant potential side effects that are of particular concern in elderly patients. We reviewed the records of ten patients with stroke treated with methylphenidate for depression during an inpatient rehabilitation program. Improvement was noted in seven patients. This suggests that methylphenidate in the treatment of post-stroke depression merits further study.

A research approach to simplifying the accrediting process of allied health programs

The operationalization and quantification of selected measures of effectiveness and their application to 25 allied health departments in junior and community colleges is described. Principal results are that the 34 measures of effectiveness suggested by experts' opinions could be reduced to 14 criteria. These could be combined into two indices of effectiveness, one of instructional effectiveness and one of administrative effectiveness. The results hold promise for simplification of the accrediting process. Part I of this article appeared in the February 1984 issue of JAH.

Development of indices of effectiveness: a quantification of the accrediting process

Two indices of effectiveness are described, one of instructional effectiveness and one of administrative effectiveness. Originally, 97 effectiveness measures were obtained from criteria published by national health professional organizations and other accrediting bodies. The Delphi survey process was used to analyze, refine, weight, and select 19 measures of instructional effectiveness and 15 measures of administrative effectiveness. A second article (May 1984) describes the operationalization and quantification of the selected measures and their application to 25 allied health departments in Texas junior and community colleges.

A process model for competency-based education

This article describes a process model for design and development of curricula. The model is based on learning theories of competency-based education. It is suggested that curricula so designed will, in conjunction with accreditation and credntialing, provide an additional mechanism for ensuring quality in professional practice.

Eliminating discipline problems by strengthening academic performance

Behavior modification procedures have typically been used to eliminate discipline problems in the classroom through reinforcement of nondisruptive behavior. This report demonstrates an alternative approach whereby discipline problems are eliminated by reinforcing relevant academic skills. Five fifth-grade boys, identified by their teacher as discipline problems, were observed. The teacher conducted 15-min performance sessions in her reading class during which written academic performance and disruptive behavior were recorded. These measures indicated that the boys' average level of disruption was 34%, while their reading performance was below 50%. When systematic token reinforcement was applied to reading performance only, the rate of disruption fell drastically, and reading performance increased. When the reinforcement procedure was withdrawn, disruption again rose, and reading performance declined. The reinstatement of reinforcement doubled reading performance and eliminated disruption.