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PurposeThe purpose of this review was to evaluate the role of biological augmentation and tissue engineering strategies in meniscus surgery. Although clinical (human), preclinical (animal), and in vitro tissue engineering studies are included here, we have placed additional focus on addressing preclinical and clinical studies reported during the 5-year period used in this review in a systematic fashion while also providing a summary review of some important in vitro tissue engineering findings in the field over the past decade.MethodsA search was performed on PubMed for original works published from 2009 to March 31, 2014 using the term "meniscus" with all the following terms: "scaffolds," "constructs," "cells," "growth factors," "implant," "tissue engineering," and "regenerative medicine." Inclusion criteria were the following: English-language articles and original clinical, preclinical (in vivo), and in vitro studies of tissue engineering and regenerative medicine application in knee meniscus lesions published from 2009 to March 31, 2014.ResultsThree clinical studies and 18 preclinical studies were identified along with 68 tissue engineering in vitro studies. These reports show the increasing promise of biological augmentation and tissue engineering strategies in meniscus surgery. The role of stem cell and growth factor therapy appears to be particularly useful. A review of in vitro tissue engineering studies found a large number of scaffold types to be of promise for meniscus replacement. Limitations include a relatively low number of clinical or preclinical in vivo studies, in addition to the fact there is as yet no report in the literature of a tissue-engineered meniscus construct used clinically. Neither does the literature provide clarity on the optimal meniscus scaffold type or biological augmentation with which meniscus repair or replacement would be best addressed in the future. There is increasing focus on the role of mechanobiology and biomechanical and biochemical cues in this process, however, and it is hoped that this may lead to improvements in this strategy.ConclusionsThere appears to be significant potential for biological augmentation and tissue engineering strategies in meniscus surgery to enhance options for repair and replacement. However, there are still relatively few clinical studies being reported in this regard. There is a strong need for improved translational activities and infrastructure to link the large amounts of in vitro and preclinical biological and tissue engineering data to clinical application.Level of evidenceLevel IV, systematic review of Level I-IV studies.

Objective: To compare the long-term outcomes of immediate drainage versus the postponed-drainage approach in patients with infected necrotizing pancreatitis. Background: In the randomized POINTER trial, patients assigned to the postponed-drainage approach using antibiotic treatment required fewer interventions, as compared with immediate drainage, and over a third were treated without any intervention. Methods: Clinical data of those patients alive after the initial 6-month follow-up were re-evaluated. The primary outcome was a composite of death and major complications. Results: Out of 104 patients, 88 were re-evaluated with a median follow-up of 51 months. After the initial 6-month follow-up, the primary outcome occurred in 7 of 47 patients (15%) in the immediate-drainage group and 7 of 41 patients (17%) in the postponed-drainage group (RR 0.87, 95% CI 0.33–2.28; P =0.78). Additional drainage procedures were performed in 7 patients (15%) versus 3 patients (7%) (RR 2.03; 95% CI 0.56–7.37; P =0.34). The median number of additional interventions was 0 (IQR 0–0) in both groups (P =0.028). In the total follow-up, the median number of interventions was higher in the immediate-drainage group than in the postponed-drainage group (4 vs. 1, P =0.001). Eventually, 14 of 15 patients (93%) in the postponed-drainage group who were successfully treated in the initial 6-month follow-up with antibiotics and without any intervention remained without intervention. At the end of follow-up, pancreatic function and quality of life were similar. Conclusions: Also, during long-term follow-up, a postponed-drainage approach using antibiotics in patients with infected necrotizing pancreatitis results in fewer interventions as compared with immediate drainage and should therefore be the preferred approach. Trial registration: ISRCTN33682933 [ABSTRACT FROM AUTHOR]

BACKGROUND: Chemerin, an inflammatory adipokine, is upregulated in preeclampsia, and its placental overexpression results in preeclampsia-like symptoms in mice. Statins may lower chemerin. METHODS: Chemerin was determined in a prospective cohort study in women suspected of preeclampsia and evaluated as a predictor versus the sFlt-1 (soluble fms-like tyrosine kinase-1)/PlGF (placental growth factor) ratio. Chemerin release was studied in perfused placentas and placental explants with or without the statins pravastatin and fluvastatin. We also addressed statin placental passage and the effects of chemerin in chorionic plate arteries. RESULTS: Serum chemerin was elevated in women with preeclampsia, and its addition to a predictive model yielded significant effects on top of the sFlt-1/PlGF ratio to predict preeclampsia and its fetal complications. Perfused placentas and explants of preeclamptic women released more chemerin and sFlt-1 and less PlGF than those of healthy pregnant women. Statins reversed this. Both statins entered the fetal compartment, and the fetal/maternal concentration ratio of pravastatin was twice that of fluvastatin. Chemerin constricted plate arteries, and this was blocked by a chemerin receptor antagonist and pravastatin. Chemerin did not potentiate endothelin-1 in chorionic plate arteries. In explants, statins upregulated low-density lipoprotein receptor expression, which relies on the same transcription factor as chemerin, and NO release. CONCLUSIONS: Chemerin is a biomarker for preeclampsia, and statins both prevent its placental upregulation and effects, in an NO and low-density lipoprotein receptor–dependent manner. Combined with their capacity to improve the sFlt-1/PlGF ratio, this offers an attractive mechanism by which statins may prevent or treat preeclampsia. [ABSTRACT FROM AUTHOR]

Recent years have seen a rise in the efforts to implement diversity topics into medical education, using either a "narrow" or a "broad" definition of culture. These developments urge that outcomes of such efforts are systematically evaluated by mapping the curriculum for diversity-responsive content. This study was aimed at using an intersectionality-based approach to define diversity-related learning objectives and to evaluate how biomedical and sociocultural aspects of diversity were integrated into a medical curriculum in the Netherlands. We took a three-phase mixed methods approach. In phase one and two, we defined essential learning objectives based on qualitative interviews with school stakeholders and diversity literature. In phase three, we screened the written curriculum for diversity content (culture, sex/gender and class) and related the results to learning objectives defined in phase two. We identified learning objectives in three areas of education (medical knowledge and skills, patient-physician communication, and reflexivity). Most diversity content pertained to biomedical knowledge and skills. Limited attention was paid to sociocultural issues as determinants of health and healthcare use. Intersections of culture, sex/gender and class remained mostly unaddressed. The curriculum's diversity-responsiveness could be improved by an operationalization of diversity that goes beyond biomedical traits of assumed homogeneous social groups. Future efforts to take an intersectionality-based approach to curriculum evaluations should include categories of difference other than culture, sex/gender and class as separate, equally important patient identities or groups.

Despite a growing diversity within society and health care, there seems to be a discrepancy between the number of cultural minority physicians graduating and those in training for specialization (residents) or working as a specialist in Dutch academic hospitals. The purpose of this article is to explore how performance appraisal in daily medical practice is experienced and might affect the influx of cultural minority physicians into specialty training. A critical diversity study was completed in one academic hospital using interviews (N = 27) and focus groups (15 participants) with cultural minority physicians and residents, instructing specialists and executives of medical wards. Data were digitally recorded and transcribed verbatim. A thematic and integral content analysis was performed. In addition to explicit norms on high motivation and excellent performance, implicit norms on professionalism are considered crucial in qualifying for specialty training. Stereotyped imaging on the culture and identity of cultural minority physicians and categorical thinking on diversity seem to underlie daily processes of evaluation and performance appraisal. These are experienced as inhibiting the possibilities to successfully profile for selection into residency and specialist positions. Implicit criteria appear to affect selection processes on medical wards and possibly hinder the influx of cultural minority physicians into residency and making academic hospitals more diverse. Minority and majority physicians, together with the hospital management and medical education should target inclusive norms and practices within clinical practice.

Between 1970 and 1990, the Dutch working group "Empirical Introduction to Chemistry" developed a secondary school chemistry education curriculum based on the educational vision of the mathematicians van Hiele and van Hiele-Geldof. This approach viewed learning as a process in which students must go through discontinuous level transitions characterized by linguistic changes. Transposed to chemistry education, the first transition is from the ground level to the descriptive level, where students learn to describe regularities in chemical phenomena. This transition is followed by a transition to the theoretical level, where students learn the structure of these regularities. In this article, the researchers introduce the qualitative concept of "chemical element", expand it to address quantitative formulas for gases, and explain it using the concept "chemical atom" as an indivisible unity. The researchers qualitatively analyze transcripts of discussions both between students and between students and their teacher to look for evidence of chemistry learning in accordance with the theoretical expectations. The results show the applicability of the Van Hiele theory of level transitions for chemistry learning. In retrospect, more attention should have been paid to necessary idealizations to arrive at the desired chemical concepts.

Background: Surgery induces high rates of cognitive disorders, persisting for up to 12 months in elderly adults. This review aimed to assess the currently debated preventive effect of perioperative ketamine on postoperative delirium and postoperative neurocognitive disorders (POND). Materials and methods: Systematic review and meta-analysis including all randomized controlled trials investigating the effects of perioperative ketamine administration in adult patients compared to placebo or no intervention on postoperative deliriumand/or POND between January 2007 and April 2022. Database searches were conducted in PubMed, Medline, Embase, Scopus, and Central. Random effects models were used to pool overall estimates. The GRADE approach was used to assess the quality of the evidence. Results: From 1379 records screened, 14 randomized controlled trials with 1618 patients randomized met our inclusion criteria with a high level of consensus among reviewers, amongst whom 50% were at low-moderate risk of bias. There was no between-group difference in postoperative delirium[8 trials, 1265 patients, odds ratio (OR) 0.93, 95%CI (0.51-1.70), I2=28%] and POND [5 trials, 494 patients, OR 0.52, 95% CI (0.15-1.80); I2=78%]. There was no significant between-group difference in postoperative psychological adverse effects, level of pain, hospital length of stay, or mortality. Between-group subgroup analyses showed no difference in delirium or POND incidence according to surgical setting, ketamine dose, mode of administration, combination or not with other drug(s), and assessment timing or definition of cognitive disorders. Conclusion: Perioperative ketamine does not prevent postoperative delirium or POND. Significant study heterogeneity suggests that standardized measures for POND assessment and a specific focus on patients at high risk for POND should be used to improve the comparability of future studies. [ABSTRACT FROM AUTHOR]