Simplifying The Price Elasticity Of Demand

Ockham’s Razor is a reminder to keep things simple, but this principle is often ignored in the elasticity chapters of many economics textbooks.  Many texts invoke slope unnecessarily and in contradictory ways. Discussions of the determinants of the price elasticity of demand have the potential to further confuse students, as do elasticity estimates that are dated and inappropriate. Principles instructors could better explain the price elasticity of demand by concentrating on the price-quantity point on a demand curve and the mid-point formula, while avoiding rotating demand curves and relying less on simplistic determinants and outdated estimates

Robot-assisted pancreatic surgery—optimized operating procedures: set-up, port placement, surgical steps

Even in most complex surgical settings, recent advances in minimal-invasive technologies have made the application of robotic-assisted devices more viable. Due to ever increasing experience and expertise, many large international centers now offer robotic-assisted pancreatic surgery as a preferred alternative. In general however, pancreatic operations are still associated with high morbidity and mortality, while robotic-assisted techniques still require significant learning curves. As a prospective post-marketing trial, we have established optimized operating procedures at our clinic. This manuscript intends to publicize our standardized methodology, including pre-operative preparation, surgical set-up as well as the surgeons' step-by-step actions when using pancreatic-assisted robotic surgery. This manuscript is based on our institutional experience as a high-volume pancreas operating center. We introduce novel concepts that should standardize, facilitate and economize the surgical steps in all types of robotic-assisted pancreatic surgery. The "One Fits All" principle enables single port placement irrespective of the pancreatic procedure, while the "Reversed 6-to-6 Approach" offers an optimized manual for pancreatic surgeons using the robotic console. Novel and standardized surgical concepts could guide new centers to establish a robust, efficient and safe robotic-assisted pancreatic surgery program

Robotic-assisted pancreatic surgery in the elderly patient: experiences from a high-volume centre

Background: Robotic-assisted pancreatic surgery (RPS) has fundamentally developed over the past few years. For subgroups, e.g. elderly patients, applicability and safety of RPS still needs to be defined. Given prognosticated demographic developments, we aim to assess the role of RPS based on preoperative, operative and postoperative parameters. Methods: We included 129 patients undergoing RPS at our institution between 2017 and 2020. Eleven patients required conversion to open surgery and were excluded from further analysis. We divided patients into two groups; >= 70 years old (Group 1; n = 32) and < 70 years old (Group 2; n = 86) at time of resection. Results: Most preoperative characteristics were similar in both groups. However, number of patients with previous abdominal surgery was significantly higher in patients >= 70 years old (78% vs 37%, p = 70 years old stayed significantly longer at ICU (1.8 vs 0.9 days; p = 0.037), length of hospital stay and postoperative morbidity were equivalent between the groups. Conclusion: RPS is safe and feasible in elderly patients and shows non-inferiority when compared with younger patients. However, prospectively collected data is needed to define the role of RPS in elderly patients accurately. Trial registration Clinical Trial Register: Deutschen Register Klinischer Studien (DRKS; German Clinical Trials Register). Clinical Registration Number: DRKS00017229 (retrospectively registered, Date of Registration: 2019/07/19, Date of First Enrollment: 2017/10/18)

The Multidimensional Prognostic Index in general practice: One-year follow-up study.

BACKGROUND Older patients' health problems in general practice (GP) can often not be assigned to a specific disease, requiring a paradigm shift to goal-oriented, personalised care for clinical decision making. PURPOSE To investigate the predictive value of the comprehensive geriatric assessment (CGA)-based Multidimensional Prognostic Index (MPI) in a GP setting with respect to the main healthcare indicators during the 12 months following initial evaluation. METHODS One hundred twenty-five consecutive patients aged 70 years and older were enrolled in a GP and followed up to one year. All patients underwent a CGA based on which the MPI was calculated and subdivided into three risk groups (MPI-1, 0-0.33 = low risk, MPI-2, 0.34-0.66 = moderate risk and MPI-3, 0.67-1, severe risk). Grade of Care (GC), hospitalization rate, mortality, nursing home admission, use of home care services, falls, number of general practitioner contacts (GPC), of geriatric resources (GR) and geriatric syndromes (GS) during the 12 months following initial evaluation were collected. RESULTS The MPI was significantly associated with number of GS (P < .001), GR (P < .001), GC (P < .001) as well as with the average number of GPC per year (mean 10.4, P = .046). Interestingly, the clinical judgement of the general practitioner, in this case knowing his patients for 16 years on average, was associated with adverse outcomes to a similar extent than the prediction offered by the MPI (GP/adverse outcomes and MPI/adverse outcomes P < .001). CONCLUSION The MPI is strongly associated with adverse outcomes in older GP patients and strongly predicts the number of GPC up to one year after initial evaluation. Considering the feasibility and the strong clinimetric properties of the MPI, its collection should be encouraged as early as possible to disclose risk conditions, implement tailored preventive strategies and improve cost-effectiveness of healthcare resources use

Robotic versus open pancreatic surgery: a propensity score-matched cost-effectiveness analysis

Background: Robotic pancreatic surgery (RPS) is associated with high intraoperative costs compared to open pancreatic surgery (OPS). However, it remains unclear whether several advantages of RPS such as reduced surgical trauma and a shorter postoperative recovery time could lead to a reduction in total costs outweighing the intraoperative costs. The study aimed to compare patients undergoing OPS and RPS with regards to cost-effectiveness in a propensity score-matched (PSM) analysis. Methods: Patients undergoing OPS and RPS between 2017 and 2019 were included in this monocentric, retrospective analysis. The controlling department provided financial data (costs and revenues, net loss/profit). A propensity score-matched analysis was performed or OPS and RPS (matching criteria: age, American society of anesthesiologists (ASA) score, gender, body mass index (BMI), and type of pancreatic resection) with a caliper 0.2. Results: In total, 272 eligible OPS cases were identified, of which 252 met all inclusion criteria and were thus included in the further analysis. The RPS group contained 92 patients. The matched cohorts contained 41 patients in each group. Length of hospital stay (LOS) was significantly shorter in the RPS group (12 vs. 19 days, p = 0.003). Major postoperative morbidity (Dindo/Clavien >= 3a) and 90-day mortality did not differ significantly between OPS and RPS (p > 0.05). Intraoperative costs were significantly higher in the RPS group than in the OPS group (7334euro vs. 5115euro, p revenue). Conclusions: Surgical outcomes of RPS were similar to those of OPS. Higher intraoperative costs of RPS are outweighed by advantages in other categories of cost-effectiveness such as decreased lengths of hospital stay

p35, the non-cyclin activator of Cdk5, protects podocytes against apoptosis in vitro and in vivo

Cyclin-dependent kinase-5 is widely expressed and predominantly regulated by the non-cyclin activator p35. Since we recently showed that expression of p35 in the kidney is restricted to podocytes, we examined here its function in mice in which p35 was genetically deleted. The mice did not exhibit kidney abnormalities during glomerular development or during adult life. Conditionally immortalized cultured podocytes, derived from these null mice, did not have any change in their morphology, differentiation, or proliferation. However, when these cultured podocytes were exposed to UV-C irradiation, serum depletion, puromycin aminonucleoside, or transforming growth factor-β-1, they showed increased apoptosis compared to those from wild-type mice. Levels of Bcl-2 were decreased in these null podocytes but increased after transduction with human p35. Restoration of p35 or the ectopic expression of Bcl-2 reduced the susceptibility of p35-null podocytes to apoptosis. Experimental glomerulonephritis, characterized by podocyte apoptosis and subsequent crescent formation, was utilized to test these findings in vivo. Podocyte apoptosis was significantly increased in diseased p35-null compared with wild-type mice, accompanied by increased glomerulosclerosis and decreased renal function. Our study shows that p35 does not affect glomerulogenesis but controls podocyte survival following injury, in part, by regulating Bcl-2 expression

Detection of multiple annexin autoantibodies in a patient with recurrent miscarriages, fulminant stroke and seronegative antiphospholipid syndrome.

Anti-phospholipid syndrome (APS) is one of the main causes for recurrent miscarriages. The diagnosis of APS is based on the occurrence of clinical symptoms such as thrombotic events or obstetric complications as well as the detection of antiphospholipid antibodies directed against ß2-glycoprotein I and cardiolipin, or a positive lupus anticoagulant assay. However, there is a subpopulation of patients with clinical symptoms of APS, but the lack of serological markers (seronegative APS). In addition, a large proportion of patients with unexplained recurrent miscarriages exist. These cases may be attributed, at least in part, to a seronegative APS. The presence of autoantibodies against annexins is potentially associated with APS. Here we used immunoassays and immunoblots to detect autoantibodies directed against annexin A1-5, and A8, respectively, in a patient with a seronegative APS and a history of six recurrent pregnancy losses and fulminant stroke. We found strong IgM isotype antibody reactivity directed against annexin A2 and annexin A8, and moderate to weak IgM isotype antibody reactivity directed against annexin A1, A3, and A5. Further studies will evaluate the diagnostic value of IgM isotype antibodies against annexin A1-A5, and A8 for seronegative APS and recurrent miscarriages

Low-Molecular Weight Heparin Increases Circulating sFlt-1 Levels and Enhances Urinary Elimination

Rationale: Preeclampsia is a devastating medical complication of pregnancy which leads to maternal and fetal morbidity and mortality. While the etiology of preeclampsia is unclear, human and animal studies suggest that excessive circulating levels of soluble fms-like tyrosine-kinase-1 (sFlt-1), an alternatively spliced variant of VEGF-receptor1, contribute to the signs and symptoms of preeclampsia. Since sFlt-1 binds to heparin and heparan sulfate proteoglycans, we hypothesized that the anticoagulant heparin, which is often used in pregnancy, may interfere with the levels, distribution and elimination of sFlt-1 in vivo. Objective: We systematically determined serum and urine levels of angiogenic factors in preeclamptic women before and after administration of low molecular weight heparin and further characterized the interaction with heparin in biochemical studies. Methods and Results: Serum and urine samples were used to measure sFlt-1 levels before and after heparin administration. Serum levels of sFlt-1 increased by 25% after heparin administration in pregnant women. The magnitude of the increase in circulating sFlt-1 correlated with initial sFlt-1 serum levels. Urinary sFlt-1 levels were also elevated following heparin administration and levels of elimination were dependent on the underlying integrity of the glomerular filtration barrier. Biochemical binding studies employing cation exchange chromatography revealed that heparin bound sFlt-1 had decreased affinity to negatively charged surfaces when compared to sFlt-1 alone. Conclusion: Low molecular weight heparin administration increased circulating sFlt1 levels and enhanced renal elimination. We provide evidence that both effects may be due to heparin binding to sFlt1 and masking the positive charges on sFlt1 protein