Report of the United States cooperative study of extracorporeal shock wave lithotripsy

Extracorporeal shock wave lithotripsy effectively fragments urinary calculi in the upper urinary tract and upper ureter. These fragments pass completely by 3 months in 77.4 per cent of the patients with single stones. Risk of obstruction, increased postoperative pain, need for additional urological operations and retained fragments are low for stones less than 1 cm. in size. As the number of stones treated or single stone size increases above 1 cm. the risk for these factors increases. Adjunctive urological surgical management is required in 9 per cent of the patients preoperatively and 8 per cent postoperatively. Only 0.6 per cent of the patients require some type of open operation to resolve the stone problems after extracorporeal shock wave lithotripsy. Hemorrhage, obstruction by fragments, severe pain and urinary infection all constitute known complications and require careful urological management of all patients. Hospitalization averages 2 days after treatment and patients usually return to work within a few days after they are discharged from the hospital.

Elevated levels of NAP-1/interleukin-8 are present in the airspaces of patients with the adult respiratory distress syndrome and are associated with increased mortality

The adult respiratory distress syndrome (ARDS) is characterized by increased neutrophils within the airspaces of the lungs. In order to determine if neutrophil activating protein (NAP)-1/interleukin-8 (NAP-1/IL-8) could be an important cause of neutrophil influx and activation in ARDS, we examined fluid, which was either directly aspirated or lavaged with saline from the lungs of patients with ARDS. NAP-1/IL-8 was present in significantly higher concentrations in the fluids of patients with ARDS compared with control subjects. There was a significant correlation between the percentage of neutrophils in the lavage fluids and the NAP-1/IL-8 concentration (r2 = 0.74). Furthermore, the NAP-1/IL-8 concentration of the pulmonary edema fluid was equivalent to the optimal concentration required to induce neutrophil chemotaxis in vitro. Although not all of the chemotactic activity of the edema fluid was removed by an anti-NAP-1/IL-8 affinity column, the data established that NAP-1/IL-8 is an important neutrophil chemotaxin in the airspaces of patients with ARDS. In addition, those patients with very high concentrations of NAP-1/IL-8 in their bronchoalveolar lavage fluids had a higher mortality rate than those patients with lower concentrations of NAP-1/IL-8. The correlation between NAP-1/IL-8 concentration and mortality is not paralleled by total protein concentration and mortality.

Characterization of a rabbit model of staphylococcal osteomyelitis

We previously described a rabbit osteomyelitis model that involved the direct introduction of Staphylococcus aureus into devascularized bone. To further evaluate the model, we performed experiments aimed at correlating the microbiological, radiographic, and histologic parameters involved in the development of experimental osteomyelitis. Using the strain UAMS-1, we achieved an infection rate of 75% with an inoculum as small as 2 x 10(3) colony-forming units. However, development of significant radiographic and histologic signs of disease required an inoculum of at least 2 x 10(4) colony-forming units. Radiographic signs were minimal 1 week after infection and progressed steadily to a maximum 3 weeks after infection. In contrast, histologic signs of disease were observed within 1 week and remained essentially unchanged throughout the 4-week evaluation period. Unlike the results obtained with UAMS-1, rabbits infected with the heavily encapsulated Staphylococcus aureus strain Smith diffuse exhibited little evidence of disease even when infected with 2 x 10(6) colony-forming units. The reduced virulence of strain Smith diffuse was surprising given its greatly enhanced virulence (relative to UAMS-1) in a murine peritonitis model of staphylococcal disease. These results suggest that UAMS-1 expresses virulence factors that are important in the pathogenesis of osteomyelitis and that some or all of these virulence factors are either absent or are not expressed in strain Smith diffuse. Most importantly, the results suggest that our model may be appropriate for the identification and characterization of these virulence factors.

The Incontinence Impact Questionnaire and the Urogenital Distress Inventory: a revisit of their validity in women without a urodynamic diagnosis

OBJECTIVES

We sought to assess validity of the Incontinence Impact Questionnaire (IIQ) and the Urogenital Distress Inventory (UDI) (long and short forms) in incontinent women previously urodynamically undiagnosed.

STUDY DESIGN

Post hoc analysis of responses to the IIQ and UDI questionnaires were obtained from a trial on a urethral device in community-dwelling incontinent women. Internal consistency and validity were evaluated against the 1-hour pad test.

RESULTS

Internal consistency (Cronbach's alpha) for the long forms was high for the IIQ and moderately high for the UDI, good for the IIQ-short, but poor for the UDI-short. Correlations with 1h pad test were low and non-significant for both versions. Correlation of the short with the long forms was high.

CONCLUSION

In the community-dwelling population, without a urodynamic diagnosis, neither long nor short versions of the questionnaires correlate with the severity of the urinary incontinence as shown by the pad test. The validity of the current questionnaires in women without urodynamic diagnosis is questionable.

Autocatalytic processing of the streptococcal cysteine protease zymogen: processing mechanism and characterization of the autoproteolytic cleavage sites

The autocatalytic processing of the streptococcal cysteine protease zymogen (proSCP) to active streptococcal cysteine protease (SCP) was investigated in vitro using purified protein from Streptococcus pyogenes strain B220. It was found that the autocatalytic maturation of the zymogen proceeds through the sequential appearance of at least six intermediates, five of which were characterized through a combination of N-terminal sequencing and MS. Intermediates were identified as resulting from cleavages after Lys26, Asn41, Lys101, Ala112, and Lys118. Time-course studies of the proSCP processing gave a sigmoidal activity profile and indicated that proSCP catalyses its own transformation, mainly via an intermolecular processing mechanism. A similar sequential appearance of intermediates was observed when inactive Cys192Ser proSCP was treated with native, enzymatically active SCP, thus demonstrating that the maturation can exclusively proceed by a bimolecular mechanism. It was shown that proSCP, but not mature SCP, immobilized on a Sepharose resin is capable of liberating itself from the column, indicating that the zymogen is also capable of intramolecular processing. In order to test whether the amino acid sequences at the processing sites could be used for developing new, specific substrates, 3-amino benzoic acid octapeptide derivatives based on all five characterized amino acid sequences from the autoprocessing cleavage sites were synthesized and tested for activity. The 3-amino benzoic acid derivatives have kcat/KM values ranging from 1200 to 7700.M-1.s-1, making them very good endopeptidase substrates for SCP.

Assay of urinary oxalate: six methodologies compared

To assess how well results by different methods for urinary oxalate determinations agree with each other in a clinical setting, we compared six different assays: Hodgkinson and Williams (Clin Chim Acta 36:127-132, 1972), enzymatic, modified Hodgkinson and Williams, gas chromatography, ion chromatography, and "high-pressure" liquid chromatography. For the entire group of samples, the mean value by each method agreed relatively closely, although the enzymatic procedure produced a somewhat higher value. All six methods had large coefficients of variation within (8-58%) and between (15-88%) assays. In addition, analytical recovery by most assays was more than 100% of the added oxalate. Analytical recovery of 10 micrograms of oxalate added per milliliter of urine specimen ranged from 86 to 237%; for 20 micrograms/mL it was 83 to 320%. Thus for the six methods evaluated, no single method appeared to be superior to the others.

Association of a Health Equity Curriculum With Medical Students' Knowledge of Social Determinants of Health and Confidence in Working With Underserved Populations

IMPORTANCE

National organizations recommend that medical schools train students in the social determinants of health.

OBJECTIVE

To develop and evaluate a longitudinal health equity curriculum that was integrated into third-year clinical clerkships and provided experiential learning in partnership with community organizations.

DESIGN, SETTING, AND PARTICIPANTS

This longitudinal cohort study was conducted from June 2017 to October 2020 to evaluate the association of the curriculum with medical students' self-reported knowledge of social determinants of health and confidence working with underserved populations. Students from 1 large medical school in the southeastern US were included. Students in the class of 2019 and class of 2020 were surveyed at baseline (before the start of their third year), end of the third year, and graduation. The class of 2018 (No curriculum) was surveyed at graduation to serve as a control. Data analysis was conducted from June to September 2020.

EXPOSURES

The curriculum began with a health equity simulation followed by a series of modules. The class of 2019 participated in the simulation and piloted the initial 3 modules (pilot), and the class of 2020 participated in the simulation and the full 9 modules (full).

MAIN OUTCOMES AND MEASURES

A linear mixed-effects model was used to evaluate the change in the self-reported knowledge and confidence scores over time (potential scores ranged from 0 to 32, with higher scores indicating higher self-reported knowledge and confidence working with underserved populations). In secondary analyses, a Kruskal-Wallis test was conducted to compare graduation scores between the no, pilot, and full curriculum classes.

RESULTS

A total of 314 students (160 women [51.0%], 205 [65.3%] non-Hispanic White participants) completed at least 1 survey, including 125 students in the pilot, 121 in the full, and 68 in the no curriculum classes. One hundred forty-one students (44.9%) were interested in primary care. Total self-reported knowledge and confidence scores increased between baseline and end of clerkship (15.4 vs 23.7, P = .001) and baseline and graduation (15.4 vs 23.7, P = .001) for the pilot and full curriculum classes. Total scores at graduation were higher for the pilot curriculum (median, 24.0; interquartile range [IQR], 21.0-27.0; P = .001) and full curriculum classes (median, 23.0; IQR, 20.0-26.0; P = .01) compared with the no curriculum class (median, 20.5; IQR, 16.25-24.0).

CONCLUSIONS AND RELEVANCE

In this cohort study of medical students, a dedicated health equity curriculum was associated with a significant improvement in students' self-reported knowledge of social determinants of health and confidence working with underserved populations.

A peptide from alveolar macrophages that releases neutrophil enzymes into the lungs in patients with the adult respiratory distress syndrome

A monoclonal antibody has been made to a peptide that is released by human alveolar macrophages. This enzyme-releasing peptide (ERP) causes neutrophils to secrete azurophilic granule enzymes. Normal subjects, patients with pulmonary fibrosis, and patients with sarcoidosis had similar concentrations of this peptide in their bronchoalveolar lavage fluids. However, patients with the adult respiratory distress syndrome (ARDS) had about 2.7 times higher concentrations in their lavage fluids. The enzyme-releasing activity in the lavage fluids was significantly correlated with 2 indices of the severity of the clinical illness in patients with ARDS, the APACHE score, and the chest radiograph score. The correlation was diminished or ablated by removing the peptide with the monoclonal antibody bound to staphylococcal Sepharose 4B. This peptide accounted for 62.08% (SD = 15.88%) of the enzyme-releasing activity in fluids from lungs of patients with ARDS and 86.39% (SD = 24.46%) of the activity in fluids from lungs of normal control subjects. Therefore, ERP is the major neutrophil enzyme-releasing agent in the bronchoalveolar lavage fluid from patients with ARDS and from normal persons. There was a significant correlation between the neutrophil enzyme-releasing activity and the ERP concentrations in BAL of patients with ARDS. These observations suggest that modulation of neutrophil function by ERP significantly controls the protease and peroxidase loads in the lungs of patients with ARDS.

Early and late mortality after myocardial infarction in men and women: prospective observational study

OBJECTIVE

To compare characteristics, management, and outcome of myocardial infarction (MI) in men and women.

DESIGN

Prospective observational study.

SETTING

District general hospital in southwest Scotland.

PARTICIPANTS

966 men and 597 women admitted with first MI between 1994 and 2000 with follow up to the end of 2001.

RESULTS

393 (40.7%) men and 305 (51.1%) women died during a median follow up of 3.4 years for the survivors. Univariate analysis indicated an excess mortality among women (hazard ratio (HR) 1.45, 95% confidence interval (CI) 1.25 to 1.68), which disappeared after adjustment for age, smoking, co-morbidity, previous vascular disease, diabetes, hypertension, and social deprivation (HR 1.02, 95% CI 0.87 to 1.20). There was also an excess early mortality within 30 days among women (HR 1.54, 95% CI 1.20 to 1.98), though this did not retain significance after adjustment for the same covariates (HR 1.04, 95% CI 0.79 to 1.37). Small and insignificant differences were found in the proportion of men and women receiving thrombolysis on admission and secondary prophylactic drugs at discharge, except for statins and beta blockers, which were respectively more (adjusted odds ratio 1.48, 95% CI 1.10 to 1.98) and less (adjusted odds ratio 0.78, 95% CI 0.60 to 1.00) commonly prescribed to women.

CONCLUSION

Results suggest that the poorer outcome for women after MI reported in other studies may reflect sex bias in management as well as differences in age and co-morbidity and support the view that if women have access to the same quality of care as men then survival will be the same.

Evidence-based clinical improvement for mechanically ventilated patients

Bundling or grouping together evidence-based interventions to improve care for the mechanically ventilated patient was piloted by a 10-bed medical-surgical critical care unit of a hospital. The bundled care interventions included: (a) keeping the head of bed elevated at 30 degrees, (b) instituting daily interruption of continuous sedative infusion, (c) assessing readiness to wean using a rapid-wean assessment guide, (d) initiating deep venous thrombosis prophylaxis, and (e) implementing peptic ulcer disease prophylaxis. The interventions were implemented using a plan-do-check-act quality-improvement methodology. Results indicated that the use of bundled interventions for mechanically ventilated patients could decrease average ventilator times and average length of stay with no concomitant increase in reintubations. Average mortality rates and the number of adverse events per 100 patient days also were reduced.

Evolution of practice in the management of parapneumonic effusion and empyema in children

AIM

To assess the evolution in management of children with parapneumonic effusion and empyema in a tertiary referral centre.

METHOD

We conducted a retrospective case note review of paediatric patients with parapneumonic effusion, pleural effusion and pleural empyema between December 2006 and December 2015. Digital database searches were performed to identify demographic data, referring hospital, radiological and microbiological investigations. Length of stay and morbidity were analysed.

RESULTS

One hundred fifteen patients had 159 interventions over the study period. Fifty-four children were successfully treated with intercostal drainage (ICD) and urokinase fibrinolysis alone. There were 19 primary video assisted thoracoscopic surgeries (VATS) and 12 VATS after initial intercostal drains. Thirty-three children required a thoracotomy, a reduction of 26% from the previous era (p=0.009). The median length of stay was 9days (range 2-54).

CONCLUSION

Parapneumonic effusion can be successfully treated with intercostal drainage and intrapleural fibrinolytics, but a proportion requires further surgical intervention. In our hospital, increased utilisation of fibrinolysis and VATS occurred with a corresponding decrease in the need for thoracotomy. Patients needing thoracotomy all had severe disease on ultrasound, but ultrasound did not reliably predict failure of fibrinolytic therapy.

LEVEL OF EVIDENCE

III.

Discovery of RWJ-54428 (MC-02,479), a new cephalosporin active against resistant gram-positive bacteria

The discovery of RWJ-54428 (MC-02,479), a new cephalosporin displaying promising activity against sensitive and resistant Gram-positive bacteria, is described. Progressive structural modification from the previously reported 3-phenylthiocephem MC-02,331 afforded an overall increase in potency against MRSA while retaining other key properties such as acceptable solubility and serum binding. Evaluation of the in vitro potency and in vivo efficacy of a series of closely related compounds resulted in selection of RWJ-54428 (MC-02,479) for further studies.

Microwave sterilization of polyethylene catheters for intermittent self-catheterization

A standard household 650 W microwave oven was used to sterilize polyethylene catheters of the type used for intermittent self-catheterization. The catheters were infected with Proteus sp. bacteria and microwaved at 650 W for periods of 2, 4, 6 and 8 minutes. The effect of microwaving was assessed by determining the resultant colony counts following catheter culture. It was determined that 6 minutes of microwaving were required to achieve sterility. It is suggested that use of a microwave oven is a reliable and cost-effective method of sterilizing polyethylene catheters for intermittent self-catheterization.

Seasonal variation in paediatric blood lead levels in Syracuse, NY, USA

Venous blood lead values for 2,633 children aged 0-4 years in Syracuse, New York, collected between 1 April 1992 and 31 March 1993 were summarised by census tract for study of geographic variability. A demographic exposure model is presented showing housing stock and SES (socioeconomic status) parameters as the most significant predictor variables. A seasonal trend in blood lead levels was observed with late summer values about 40% higher than late winter values for census tracts with the highest geometric mean PbB levels. Seasonal variation is compared with a biokinetic uptake model to examine hypotheses about temporal variations in soil and dust lead exposure patterns.

Characterization of the effects of lithium on phosphatidylinositol (PI) cycle activity in human muscarinic m1 receptor-transfected CHO cells

1. The effects of lithium on [3H]-inositol and [3H]-cytidine incorporation into [3H]-inositol monophosphates ([3H]-InsP1) and [3H]-cytidine monophosphorylphosphatidate ([3H]-CMP-PA), respectively, and inositol 1,4,5-trisphosphate (InsP3) and inositol 1,3,4,5-tetrakisphosphate (InsP4) mass were studied in carbachol-stimulated human m1 muscarinic receptor-transfected Chinese hamster ovary cells (m1 CHO cells). 2. Lithium alone (10 mM) had no appreciable effects on any of the four parameters measured; it was only in carbachol-stimulated cells that the effects of lithium became apparent. 3. In the presence of carbachol (1 mM), lithium (10 mM) caused a relatively rapid (within 5 min) accumulation of [3H]-InsP1 and [3H]-CMP-PA which continued up to about 20-30 min, after which accumulation slowed down. On the other hand, the elevation in InsP3 and InsP4 levels produced by carbachol was not altered by lithium in the short-term and only at later times (> 20-30 min) was the response attenuated, with InsP3 and InsP4 levels approaching basal. 4. The effects of lithium on carbachol-stimulated [3H]-InsP1 and [3H]-CMP-PA accumulation and the attenuation of the carbachol-induced elevation of InsP3 and InsP4 were all dose-dependent, with EC50s in the region of 1 mM. 5. The lithium-induced effects on [3H]-CMP-PA and InsP3 and InsP4 in carbachol-stimulated cells could be reversed, in a dose-dependent manner, by preincubation with exogenous myo-inositol (EC50 = 2-3 mM) but not by the inactive analogue scyllo-inositol, indicating that these effects occur as a consequence of depletion of inositol. 6. The temporal effects of lithium are consistent with lithium inhibiting inositol monophosphatase,causing accumulation of InsP1, resulting in lower free inositol levels. This leads to accumulation of CMP-PA and reduced PI synthesis which, once agonist-linked membrane inositol phospholipids are depleted, produces attenuated InsP3 and InsP4 responses.7. These results in ml CHO cells support the hypothesis that lithium affects the PI cycle cell signalling pathway by depletion of inositol due to inhibition of inositol monophosphatase.

Discovery of MC-02,331, a new cephalosporin exhibiting potent activity against methicillin-resistant Staphylococcus aureus

A systematic approach toward building activity against methicillin-resistant staphylococci into the cephalosporin class of beta-lactam antibiotics is described. Initial work focused on finding the optimal linkage between the cephem nucleus and a biphenyl pharmacophore, which established that a thio linkage afforded potent activity in vitro. Efforts to optimize this activity by altering substitution on the pharmacophore afforded iodophenylthio analog MC-02,002, which although highly potent against MRSA, was also highly bound to serum proteins. Further work to decrease serum protein binding showed that replacement of the iodo substituent by the positively-charged isothiouronium group afforded potent activity and reduced serum binding, but insufficient aqueous solubility. Solubility was enhanced by incorporation of a second positively-charged group into the 7-acyl substituent. Such derivatives (MC-02,171 and MC-02,306) lacked sufficient stability to staphylococcal beta-lactamase enzymes. The second positive charge was incorporated into the cephem 3-substituent in order to utilize the beta-lactamase-stable aminothiazolyl(oximino)acetyl class of 7-substituents. These efforts culminated with the discovery of bis(isothiouroniummethyl)phenylthio analog MC-02,331, whose profile is acceptable with respect to potency against MRSA, serum binding, aqueous solubility, and beta-lactamase stability.

Evaluation of calving seasons and marketing strategies in Northern Great Plains beef enterprises: I. Cow-calf systems

A bioeconomic computer model was used to evaluate alternate calving seasons in a cow-calf enterprise under range conditions representative of the Northern Great Plains. The simulated ranch utilized a rotational breeding system based on Hereford and Angus and had a fixed forage base (4,500 animal unit months of native range, 520 t of grass hay, and 183 t of alfalfa hay). Calving seasons studied were spring (SP, beginning March 15), summer (SU, beginning May 15), and fall (FA, beginning August 15). Weaning dates were October 31, December 15, and February 1, for SP, SU, and FA. The SP system was also simulated with a 5% increase in calf mortality (SP-IM), and SU with early weaning on October 31 (SU-EW). Herd size for the fixed resource was 509, 523, 519, 560, and 609 cows exposed per year for SP, SP-IM, SU, SU-EW, and FA, respectively. Corresponding values for weight weaned per cow exposed were 206, 186, 193, 153, and 145 kg. Steer calves, nonreplacement heifer calves, and cull cows were sold at the time of weaning. Quarterly cattle and feed prices used were representative of the peak, descending, valley, and ascending phases of the 1990s cattle cycle adjusted for inflation. Estimates of ranch gross margin (gross returns minus variable costs) were greatest for SP, followed by SP-IM, SU, SU-EW, and FA, and the ranks were consistent across phases of the cattle cycle. Differences between ranch gross margin for SP-IM and SU were small. In beef enterprises representative of the Northern Great Plains, with a restricted grazing season, limited access to low-cost, high-quality grazeable forage, and with calves sold at weaning, switching from early spring to a summer or fall calving date is not expected to improve profitability. If delaying calving improves calf survival, then calving in early summer may be a competitive choice.

SAR studies of anti-MRSA non-zwitterionic 3-heteroarylthiocephems

SAR studies in a series of 3-heteroarylthio substituted cephalosporins established that high activity against methicillin-resistant Staphylococcus aureus (MRSA) can be achieved with various heteroaryl substituents. Early results showed that highly lipophilic 3-heteroarylthio substituents, which were necessary for anti-MRSA activity, caused high affinity of such cephems toward serum proteins. Our earlier published efforts described discovery of zwitterionic cephems MC-02,331 and RWJ-54428 (MC-02,479), where serum binding was reduced by employing basic, positively charged functionalities attached to the 3-heteroarylthio substituent. In order to avoid low solubility problems associated with most such zwitterionic cephalosporins a wide variety of non-basic heteroaryl substituents was tested (non-zwitterionic cephems are more easily formulated as water soluble sodium salts for intravenous administration). Considerable reduction in serum binding was obtained in some analogs while maintaining high anti-MRSA potency.

Controlled trial of ornithine alpha ketoglutarate (OAKG) in patients with stroke

A double blind controlled trial of ornithine alpha-ketoglutarate (OAKG) was carried out on 50 patients admitted to the Royal Free and Royal Northern Hospitals, London, suffering from a recent stroke. Significant improvement was found in patients treated with OAKG when examined on the fifth day of therapy as compared to their control cases. The therapy was given for 5 days. When the patients in the treated and the control groups were compared 10 days after the beginning of treatment, there were no differences between the 2 groups. Implications of these findings are discussed.