Hydrolytic and depolymerising enzyme activity of Prevotella intermedia and Prevotella nigrescens

OBJECTIVE: Prevotella intermedia has been reported to be associated with periodontal disease whilst P. nigrescens has predominantly been isolated from more specific conditions and healthy sites. The aim of the present study was to compare the enzyme activity of these species.
MATERIALS AND METHODS Nine strains of P. intermedio and 12 strains of P. nigrescens were studied. Lipolytic. saccharolytic, nucleolytic and proteolytic activity was determined by traditional microbiological and chromo-genic substrate methods.
RESULTS: All strains hydrolysed gelatine, casein. DNA and RNA. Lipase activity was produced by all strains except P. nigrescens ATCC 33563^T. Lipolytic activity of P. nigrescens strains decreased as the environmental glucose concentration was increased. Only two strains, both P. intermedia , hydrolysed benzyl-arg-p-nitroanilide. All strains hydrolysed alkaline pnitrophenolphosphate (except P. intermedia DAL 100). produced glycylprolyl dipeptidase activity and demonstrated elastase-like activity. All but three strains (2 P. intermedia and I P. nigrescens) hydrolysed suc-ala-ala-pro-phe-p-nitroanilide. Overall, no qualitatively analysed enzyme activity was exclusive to all strains of either species. Quantitatively analysed activity exhibited a high degree of variability both within and between species.
CONCLUSIONS: P. intermedia and P. nigrescens degrade natural and synthetic substrates, but intra- and interspec-ies activity is variable.     

Drivers of Cost for Pancreatic Surgery: It’s Not About Hospital Volume

Background

Outcomes for pancreatic resection have been studied extensively due to the high morbidity and mortality rates, with high-volume centers achieving superior outcomes. Ongoing investigations include healthcare costs, given the national focus on reducing expenditures. Therefore, we sought to evaluate the relationships between pancreatic surgery costs with perioperative outcomes and volume status.

Methods

We performed a retrospective analysis of 27,653 patients who underwent elective pancreatic resections from October 2013 to June 2017 using the Vizient database. Costs were calculated from charges using cost–charge ratios and adjusted for geographic variation. Generalized linear modeling adjusting for demographic, clinical, and operation characteristics was performed to assess the relationships between cost and length of stay, complications, in-hospital mortality, readmissions, and hospital volume. High-volume centers were defined as hospitals performing?≥?19 operations annually.

Results

The unadjusted mean cost for pancreatic resection and corresponding hospitalization was $20,352. There were no differences in mean costs for pancreatectomies performed at high- and low-volume centers [??$1175, 95% confidence interval (CI) ??$3254 to $904, p?=?0.27]. In subgroup analysis comparing adjusted mean costs at high- and low-volume centers, there was no difference among patients without an adverse outcome (??$99, 95% CI ??$1612 to 1414, p?=?0.90), one or more adverse outcomes (??$1586, 95% CI ??$4771 to 1599, p?=?0.33), or one or more complications (??$2835, 95% CI ??$7588 to 1919, p?=?0.24).

Conclusions

While high-volume hospitals have fewer adverse outcomes, there is no relationship between surgical volume and costs, which suggests that, in itself, surgical volume is not an indicator of improved healthcare efficiency reflected by lower costs. Patient referral to high-volume centers may not reduce overall healthcare expenditures for pancreatic operations.

     

The inter‐rater reliability between nurse‐assessors clinically assessing infection of chronic wounds using the WUWHS criteria

The aim of this study was to determine the inter‐rater reliability between one expert‐nurse and four clinical‐nurses who were asked to clinically assess infection of chronic wounds by using the World Union of Wound Healing Societies (WUWHS) criteria. A quasi‐experimental design was used to collect the data. In comparison to phase 1 in which ‘open questions’ were asked, in phase 2 a pre‐printed form (checklist) was introduced. In both phases, 55 chronic wounds were clinically assessed. For each WUWHS criterion the inter‐rater reliability of signs and symptoms was expressed by Cohens Kappa (κ). A substantial agreement (κ ≥ 0·6) was considered as adequate. In both phases pocketing (p < 0·02), and erythema (p < 0·004) scored statistically significant results. Phase 2 showed higher inter‐rater agreements compared with phase 1 (three substantial agreements (easily bleeding/friable granulation tissue, delayed healing, increasing exudate), an almost perfect‐ and a perfect agreement for malodour and pain, respectively. According to the results it can be concluded that the clinical assessment of infection of chronic wounds may be better supported by a pre‐printed form than making use of an ‘open questions’ form. To provide this with a higher level of evidence, there is need for more well conducted studies.     

Physiological effects of synthetic atrial natriuretic factor in normal conscious dogs

The objective of this study was to examine the integrative physiologic effects of atrial natriuretic factor (ANF). Synthetic 99-126 ANF was administered to 6 normal conscious dogs as two consecutive infusions (0.02 and 0.1 microgram/kg/min respectively) each over 30 min: each infusion was preceded by a priming dose of 1 microgram/kg. With the first infusion, mean arterial pressure declined from 113 +/- 2 to 103 +/- 4 mmHg, pulmonary capillary wedge pressure declined from 9.6 +/- 0.5 to 7.2 +/- 0.7 mmHg and right atrial pressure declined from 9.8 +/- 0.4 to 8.0 +/- 0.7 mmHg (all p less than 0.05). No change in heart rate was seen. Despite very high plasma ANF concentrations, no further decline in arterial or central filling pressures were seen in the second infusion. In contrast, cardiac output declined progressively from 3.8 +/- 0.2 to 2.8 +/- 0.21/min (p less than 0.01) by the end of second infusion. Plasma renin activity declined from 2.2 +/- 0.7 to 0.9 +/- 0.3 ng/ml/hr (p less than 0.05) while plasma norepinephrine remained unchanged. Urine output and sodium excretion increased in a dose dependent manner. The diverse time course of the hemodynamic, renal and neuroendocrine effects suggests these effects of ANF are mediated by different mechanisms. Furthermore, the failure of heart rate and plasma norepinephrine to increase despite a significant decline in blood pressure and cardiac output suggests ANF may have a depressant effect on the sympathetic nervous system.     

Malabsorption and nutritional balance in the ICU: fecal weight as a biomarker: a prospective observational pilot study

Introduction  

Malabsorption, which is frequently underdiagnosed in critically ill patients, is clinically relevant with regard to nutritional balance and nutritional management. We aimed to validate the diagnostic accuracy of fecal weight as a biomarker for fecal loss and additionally to assess fecal macronutrient contents and intestinal absorption capacity in ICU patients.