Despite this,

Despite this, Selleck CT99021 19% of physicians report using amiodarone as first-line prophylaxis of postoperative AF. Data directly comparing the efficacy of these agents in preventing postoperative AF are lacking.\n\nObjective: To determine whether intravenous

metoprolol and amiodarone are equally effective in preventing postoperative AF after cardiac surgery.\n\nDesign: Randomized, prospective, equivalence, open-label, multicenter study. ( registration number: NCT00784316)\n\nSetting: 3 cardiac care referral centers in Finland.\n\nPatients: 316 consecutive patients who were hemodynamically stable and free of mechanical ventilation and AF within 24 hours after cardiac surgery.\n\nIntervention: Patients were randomly assigned to receive 48-hour infusion of metoprolol, 1 to 3 mg/h, according to heart rate, or amiodarone, 15 mg/kg of body weight

daily, with a maximum daily dose of 1000 mg, starting 15 to 21 hours after cardiac surgery.\n\nMeasurements: The primary end point was the occurrence of the first AF episode or completion of the 48-hour infusion.\n\nResults: Atrial fibrillation occurred in 38 of 159 (23.9%) patients in the metoprolol group and 39 of 157 (24.8%) patients in the amiodarone group (P = 0.85). However, the difference (-0.9 percentage point [90% CI, -8.9 to 7.0 percentage points]) does not meet the prespecified equivalence margin of 5 percentage points. The adjusted hazard ratio of the metoprolol group compared with the amiodarone group was 1.09 (95% CI, 0.67 to 1.76).\n\nLimitations: Caregivers were not blinded to treatment allocation, and the trial evaluated only stable patients who were not at particularly elevated risk for AF. The withdrawal of preoperative beta-blocker therapy may have increased the risk for AF in the amiodarone group.\n\nConclusion: The occurrence of AF was similar in the metoprolol and amiodarone groups. However, because of the wide range of the CIs, the authors cannot conclude that the 2 treatments were equally

“Background: TSH receptor click here antibodies (TRAb) are the diagnostic hallmark of Graves’ disease (GD) and immunoassays for their detection have been available for more than 30 years over three generations of laboratory methods. Despite a growing body of data produced by clinical and laboratory research which demonstrates its elevated sensitivity and specificity, TRAb testing is poorly used for diagnosing GD.\n\nThe aim of our systematic review and meta-analysis is to verify the diagnostic performance of TRAb detected with 2nd and 3rd generation immunoassay methods.\n\nMethods: We searched for English articles using MEDLINE with the search terms “TSH receptor antibody assay”, “TSH Receptor antibody tests” and “Graves’ disease”.

(C) 2011 Elsevier B V All rights reserved “
“Recruitment of

(C) 2011 Elsevier B.V. All rights reserved.”
“Recruitment of the growth factor receptor-bound protein 2 (Grb2) by the plasma membrane-associated adapter protein downstream

of kinase 3 (Dok-3) attenuates signals transduced by the B cell antigen receptor (BCR). Here we describe molecular details of Dok-3/Grb2 signal integration and function, showing that the Lyn-dependent activation of the BCR transducer kinase Syk is attenuated by Dok-3/Grb2 in a site-specific manner. This process is associated with the SH3 domain-dependent translocation of Dok-3/ Grb2 complexes into BCR microsignalosomes and augmented phosphorylation of the inhibitory Lyn NSC 23766 target SH2 domain-containing inositol 5′ phosphatase. Hence, our findings imply that Dok-3/ Grb2 modulates the balance between activatory and inhibitory Lyn functions with the aim to adjust BCR signaling efficiency.”
“Recombinant Escherichia coli strains for the production of valuable products are usually generated by transformation with plasmid expression vectors. However, in spite of their usefulness,

common problems associated with plasmid use include segregrational and structural instability as well as undesired copy-number effects. A viable alternative to plasmid use is chromosomal gene integration. Z-IETD-FMK With the purpose of facilitating the process of stable strain generation, a novel chromosomal integration vector was developed and tested. We describe the Alvespimycin construction and use of novel expression vector pLoxGentrc that contains the strong trc promoter (P-trc), a multiple cloning site, the T1 and T2 rrnB terminator sequences, the lacl(q) gene and the aacC1 gene conferring gentamicin resistance

flanked by two loxP sites. As a demonstration of utility, melanin-producing strains of E. coli were generated employing this vector. Melanin is a polymer synthesized by the enzyme tyrosinase using L-tyrosine as substrate. The melA gene encoding a tyrosinase from Rhizobium etli was ligated to pLoxGentrc to generate pLoxGentrcmelA. This plasmid was transformed into E. coli W3110 to generate a melanin-producing strain. A region from this plasmid including P(trc)melA, T1 and T2 rrnB and the aacC1 gene was amplified by PCR employing primers with 45 b regions of homology to the lacZ gene. The PCR product was electroporated into strain W3110 that expressed the lambda-Red enzymes. From this experiment, strain W3110P(trc)melA, was obtained having the melA gene inserted in the lacZ locus. Fermentor cultures with strain W3110/pLoxGentrcmelA grown in the presence and absence of gentamicin as well as W3110P(trc)melA without antibiotic revealed that the latter displays high genetic stability as well as the highest melanin titer. Vector pLoxGentrc should be useful during strain generation processes, enabling direct comparison of plasmid and chromosome-based production systems. (c) 2012 Elsevier Inc. All rights reserved.

The microspheres of various compositions were prepared by an oil-

The microspheres of various compositions were prepared by an oil-in-oil emulsion-solvent

evaporation method. The effect of complexation and presence of cellulose polymers on entrapment efficiency, particle size, and drug release had been investigated. The solid-state characterization was performed by Fourier transform infrared spectroscopy, thermogravimetry, differential scanning calorimetry, and powder X-ray diffractometry. The morphology of MIC was examined by scanning electron microscopy. The in vitro drug release profiles from these microspheres showed the desired biphasic release behavior. After enhancing the solubility of prednisolone by inclusion into HP beta CD, the drug release was easily modified in the microsphere formulation. It was also demonstrated that the CDs in these microspheres were able to modulate several properties such as morphology, drug loading, and AP26113 cell line release properties. The release kinetics of prednisolone from microspheres followed quasi-Fickian and first-order release mechanisms. In addition to this, the f (2)-metric technique was used to check the equivalency of

dissolution profiles of the optimized formulation before and after stability studies, and it was found to be similar. LOXO-101 order A good outcome, matrix microspheres (coded as MIC5) containing PRD-HP beta CD complex, showed sustained release of drug (95.81%) over a period of 24 h.”
“Objective: We previously reported the epidemiology of 2009 Influenza A (H1N1) in our pediatric healthcare facility in New York City during the first wave of illness (May-July 2009). We hypothesized that compared with the first wave, the second wave would be characterized by increased severity of illness and mortality.\n\nDesign: Case series conducted VX-680 Cell Cycle inhibitor from May 2009 to April 2010.\n\nSetting: Pediatric emergency departments and inpatient facilities of New York-Presbyterian

Hospital.\n\nPatients: All hospitalized patients divided by 18 yrs of age with positive laboratory tests for influenza A.\n\nMeasurements and Main Results: We compared severity of illness during the first and second wave assessed by the number of hospitalized children, including those in the pediatric intensive care unit, bacterial superinfections, and mortality rate. Compared to the first wave, fewer children were hospitalized during the second wave (n = 115 vs. 76), but a comparable portion were admitted to the pediatric intensive care unit (30.4% vs. 19.7%; p = .10). Pediatric Risk of Mortality III scores, length of hospitalization in the pediatric intensive care unit, incidence of respiratory failure and pneumonia, and peak oxygenation indices were similar during both waves. Bacterial superinfections were comparable in the first vs. second wave (3.5% vs. 1.3%).

The exponential parameters of the Gaussians are variationally opt

The exponential parameters of the Gaussians are variationally optimized with the aid of the analytical energy gradient determined with respect to those parameters. The calculated state energies are compared with the available experimental data. (C) 2012 American Institute of Physics. []“
“Purpose: To determine the rates of globe-sparing treatment and useful final visual function in patients with primary lacrimal sac/nasolacrimal duct carcinomas treated with multidisciplinary therapy.\n\nMethods: The medical records of 14 patients with primary lacrimal sac/nasolacrimal duct carcinoma treated at 1 institution were retrospectively reviewed.\n\nResults:

The patients were 9 men and 5 women; the median age at diagnosis was 58.5 years (range, 45-73 years). Seven patients presented with epiphora, 7 with a palpable check details mass in the inferomedial orbit, and 2 with dacryocystitis. In 3 patients, the diagnosis of cancer was not considered

until during or after dacryocystorhinostomy. Seven patients had squamous cell carcinoma, 2 transitional cell carcinoma, 2 adenoid cystic carcinoma, and 1 each adenocarcinoma, poorly differentiated carcinoma, and inverted papilloma with carcinoma in situ transformation. Nine Napabucasin mouse patients underwent surgical resection of the lacrimal sac and nasolacrimal duct and resection of the medial upper and lower eyelids, including canaliculi, partial ethmoidectomy, and medial maxillectomy. One patient underwent lacrimal sac biopsy only as another primary malignancy was TPX-0005 discovered during the work-up for systemic disease. Four patients underwent orbital exenteration because of extensive involvement of the orbital soft tissue. Radiotherapy was recommended for 13 patients; in 1 patient, radiotherapy was not recommended because the patient had an inverted papilloma with carcinoma in situ transformation that was completely excised. The median radiation dose was 60 Gy. Eight patients received chemotherapy either concurrent with radiation therapy (5 patients), as neoadjuvant treatment (1 patient), or for progressive or metastatic disease (3 patients). The median follow-up time was 27 months (range, 6-96 months). In

10 patients, the globe was spared. In 9 of these 10 patients, visual acuity was the same as at baseline or better than 20/40 at last follow up.\n\nConclusions: With multidisciplinary therapy, the eye can be spared and reasonable visual function can be preserved in most patients with primary lacrimal sac/nasolacrimal duct carcinomas.”
“Objective: To investigate experimentally the time dependent changes of latency, amplitude, threshold of neural response in injured rat facial nerve in a nerve-crush trauma model.\n\nMaterials and Methods: Thirty Wistar rats weighing 220-280 g (12-16 week), were grouped for permanent and transient nerve injury during time course analysis of electrophysiological changes at 1st week, and 1st, 3rd and 6th months.

We evaluated the association between socioeconomic status and the

We evaluated the association between socioeconomic status and the incidence of sudden cardiac arrest, a condition that accounts for a substantial proportion of cardiovascular-related deaths, in seven large North American urban populations.\n\nMethods: Using a population-based registry, we collected data on out-of-hospital sudden cardiac arrests occurring at home or at a residential institution from Apr. 1, 2006, to Mar. 31, 2007. We limited the analysis to cardiac arrests in seven metropolitan areas in the United States (Dallas, Texas; Pittsburgh, Pennsylvania;

Portland, Oregon; and Seattle-King County, Washington) and Canada (Ottawa and Toronto, Ontario; and Vancouver, British Columbia). Each incident was linked to a census tract; tracts were classified into quartiles of median household income.\n\nResults: A total of 9235 sudden cardiac arrests were included in the analysis. For all sites combined, the incidence of sudden cardiac arrest in the lowest socioeconomic quartile was nearly double that in the highest quartile (incidence rate ratio [IRR] 1.9, 95% confidence interval [CI] 1.8-2.0). This disparity was greater among people less than 65 years old (IRR 2.7, 95% CI 2.5-3.0) than among those 65 or older (IRR 1.3, 95% CI 1.2-1.4). After adjustment for study site and for population age structure of each census

tract, the disparity across socio economic quartiles for all ages combined was greater in the United States (IRR 2.0, 95% CI 1.9-2.2)

than in Canada (IRR Galardin clinical trial 1.8, 95% CI 1.6-2.0) (p < 0.001 for interaction).\n\nInterpretation: The incidence of sudden cardiac arrest at home or at a residential institution was higher in poorer neighbourhoods of the US and Canadian sites studied, learn more although the association was attenuated in Canada. The disparity across socioeconomic quartiles was greatest among people younger than 65. The association be tween socio economic status and incidence of sudden cardiac arrest merits consideration in the development of strategies to improve survival from sudden cardiac arrest, and possibly to identify opportunities for prevention.”
“Background: Therapeutic hypothermia (TH, 30 degrees C) protects the brain from hypoxic injury. However, TH may potentiate the occurrence of lethal ventricular fibrillation (VF), although the mechanism remains unclear. The present study explored the hypothesis that TH enhances wavebreaks during VF and Si pacing, facilitates pacing-induced spatially discordant alternans (SDA), and increases the vulnerability of pacing-induced VF\n\nMethods and Results: Using an optical mapping system, epicardial activations of VF were studied in 7 Langendorff-perfused isolated rabbit hearts at baseline (37 degrees C), TH (30 degrees C), and rewarming (37 degrees C). Action potential duration (APD)/conduction velocity (CV) restitution and APD alternans (n=6 hearts) were determined by S1 pacing at these 3 stages.

The activity and expression levels of SIRT1 and expression of its

The activity and expression levels of SIRT1 and expression of its downstream lipid-metabolism genes were measured.\n\nResultsIn replicon cells, the level of ROS and MDA increased, SOD activity and the value of NAD(+)/NADH decreased, then the activity and expression level of mRNA and protein of SIRT1 reduced. Inhibition of SIRT1 decreased phosphorylation of forkhead box O1 (FoxO1), which not only upregulated SREBP-1c, FAS, ACC, SREBP-2, HMGR and HMGS genes and increased

fatty acid synthesis; see more but also downregulated PPAR- and CPT1A genes and decreased fatty acid -oxidation. Interferon treatment restored aforementioned changes. SIRT1 activator improved lipid metabolism disorders by an increase in fatty acid -oxidation and a decrease in TG and TC synthesis and inhibited HCV replication.\n\nConclusionHCV

replication decreasing NAD(+)/NADH ratio may downregulate the activity and the expression of SIRT1, then change the expression profile of lipid metabolism-related genes, thereby cause lipid metabolism disorders of hepatocytes and promote HCV replication. Treatment with SIRT1 activator ameliorates lipid metabolic AG-120 supplier disorders and inhibits HCV replication.”
“The authors report the case of a patient arrived in psychiatric ambulatory with a panic-like symtomatology. The patient refers that the symptomatology appeared after taking sibutramine. She took it with the intent to lose weight. After the disturbance beginning, the patient interrupted the sibutramine treatment but the psychiatric symptomatology didn’t regress completely. It is supposed, in the light of this new evidence and in conformity of DSM-IV criteria, the diagnosis of substance-induced

anxiety disorder with panic attack. Paroxetine and alprazolam were administered to the patient, with the resolution of the anxious symptoms. After eight months the treatment was suspended, since the patient referred to be pregnant; in any case, during the pregnancy no other panic attacks occurred. After six months from the suspension of the drugs, the patient can no longer be classified as affected by panic attack according to the DSM-IV criteria.”
“Purpose. – Acquired haemophilia A (AHA) is a rare bleeding disorder, due to the presence of an inhibitor directed against factor VIII (FVIII). About 50% of the AHA are idiopathic, while the remaining 50% are related to an underlying disorder or condition (autoimmune diseases, malignancies, postpartum, etc.).\n\nPatients and methods. – We report on a monocentric retrospective cohort of 39 patients with AHA. Data were collected and compared to recent published data.\n\nResults. – Thirty-nine patients were admitted for AHA between 1993 et 2011. Mean age at diagnosis was 71.3 years, and we noted a marked male predominance. Although the majority of patients presented a bleeding event at diagnosis (94.9%), the hemorrhagic mortality was low (2.6%).

(C) 2010 Elsevier B V All rights reserved “
“The deep sea i

(C) 2010 Elsevier B.V. All rights reserved.”
“The deep sea is the largest biome of the biosphere. The knowledge of the spatial variability of deep-sea biodiversity is one of the main challenges NVP-HSP990 of marine ecology and evolutionary biology. The choice of the observational spatial scale is assumed to play a key role for understanding processes structuring the deep-sea benthic communities and one of the most typical features of marine biodiversity distribution is the existence of bathymetric gradients. However, the analysis of biodiversity bathymetric gradients

and the associated changes in species composition (beta diversity) typically compared large depth ranges (with intervals of 500 to 1000 or even 2000 m depth among sites). To test whether significant changes in alpha and beta diversity occur also at fine-scale bathymetric gradients (i.e., within few hundred-meter depth intervals) the variability of deep-sea nematode biodiversity and assemblage composition along a bathymetric transect (200-1200 m depth) with intervals of 200 m among sampling depths, was investigated. A hierarchical sampling strategy for the

analysis of nematode species richness, beta diversity, functional (trophic) diversity, and related environmental variables, was used. The results indicate the lack of significant differences in taxonomic and functional diversity across sampling depths, but the presence AG-014699 of high beta diversity at all spatial scales investigated: between cores collected from the same box corer (on average 56%), among deployments at the same depth (58%), and between all sampling depths

(62%). Such high beta diversity is influenced by the presence of small-scale patchiness in the deep sea and is also related to the large number of rare or very rare species (typically accounting for > 80% of total species richness). Moreover, the number of ubiquitous nematode species across all sampling depths is quite low (ca. 15%). Multiple regression analyses provide evidence that such patterns could be related to the different availability, composition and size spectra of food particles in the sediments. Additionally, though to a lesser extent, our results indicate, that selective Omipalisib predation can influence the nematode trophic composition. These findings suggest that a multiple scale analysis based on a nested sampling design could significantly improve our knowledge of bathymetric patterns of deepsea biodiversity and its drivers. (C) 2013 Elsevier Ltd. All rights reserved.”
“In this study, an experimental setup is designed and built to investigate the feasibility and performance of the proposed dual-mode cascade refrigeration cycle. The apparatus can be operated in two modes: dual-stage mode and single-stage mode such that the low temperature cycle (LTC) can be operated together with the high temperature cycle (HTC) or can run independently. Experimental results validate the feasibility of independent operation of LTC.

The problem is solved in polynomial time by optimizing


The problem is solved in polynomial time by optimizing

three separate subproblems. To further reduce the complexity, three low-complexity suboptimal algorithms are then proposed when fixing partial resource. The simulation results show the performance gains of the proposed algorithms versus per-node transmit power and source-node number, and the impact of relay location is also evaluated.”
“OBJECTIVES: There is no evidence for the increasing use of percutaneous coronary intervention (PCI) compared with surgery in patients with left main coronary artery (LMCA) disease. We compared the clinical outcomes of patients with LMCA disease who had undergone PCI with those of patients who had off-pump coronary artery bypass (OPCAB) grafting.\n\nMETHODS: From January 2001 to December 2009, 899 patients with LMCA disease were treated with OPCAB (n =

553) or PCI (n = 346). Analyses using Liproxstatin-1 cost propensity-score matching were performed to minimize the selection bias. We compared major adverse cardiac and cerebrovascular events (MACCE) including death, stroke, acute myocardial infarction and target-vessel revascularization. BIX 01294 price The median follow-up was 55.9 months.\n\nRESULTS: For the 159 propensity-matched pairs, the early mortality in the OPCAB group was lower than in the PCI group (0 vs 5%, the PCI group; P < 0.001). Overall survival at 8 years was similar Navitoclax supplier between groups (88.6 +/- 3.5%, the OPCAB group vs 85.8 +/- 5.3%, the PCI group; P = 0.394). Freedom from MACCE at 8 years was significantly higher in the OPCAB than in the PCI group (83.9 +/- 5.1 vs 60.2 +/- 6.9%, P < 0.001). Although there was no intergroup difference in the risk of death [ hazard ratio (HR) for the PCI

group, 1.435; 95% confidence interval (CI), 0.62-3.31; P = 0.396], a significant difference was found in the risk of MACCE (HR for the PCI group, 4.193; 95% CI, 2.165-8.121; P < 0.001). This difference was primarily due to a higher risk of acute myocardial infarction (HR for the PCI group, 4.730; 95% CI, 0.99-22.63; P = 0.049) and higher rates of target-vessel revascularization (HR for the PCI group, 5.508; 95% CI, 1.87-16.22; P = 0.002).\n\nCONCLUSIONS: Compared with PCI, OPCAB is associated with a lower incidence of MACCE in patients with LMCA disease, determined mainly by the lower incidences of acute myocardial infarction and target-vessel revascularization. The incidence of stroke in the OPCAB group was similar to the PCI group.”
“The National Research Council issued a report in 2009 that heavily criticized the forensic sciences. The report made several recommendations that if addressed would allow the forensic sciences to develop a stronger scientific foundation. We suggest a roadmap for decomposition ecology and forensic entomology hinging on a framework built on basic research concepts in ecology, evolution, and genetics.

Obesity data were derived from the National Center for Health Sta

Obesity data were derived from the National Center for Health Statistics Behavioral Risk Factor Surveillance System. MEDLINE searches were performed using keywords, such as socioeconomic status, poverty, African American, Hispanic, race, and combined with related articles.\n\nResults: Socioeconomic cancer metabolism inhibitor deprivation may be responsible for the increased risk of breast cancer mortality in African American and Hispanic patients, as they are more likely than white American patients to be diagnosed with advanced disease. Among white women, social deprivation is related to poor breast cancer prognosis, with increased prevalence rates of high-grade, estrogen receptor

(ER)-negative tumors, similar to that of triple-negative breast cancers observed in African American

and Hispanic women. Obesity is associated with advanced breast cancer at diagnosis, high tumor proliferation rates, and more triple-negative phenotypes, indicating that it may adversely contribute to prognosis.\n\nConclusions: Most studies show an effect of SES on breast cancer incidence and prognosis. Research should focus on the influence of social deprivation on breast cancer characteristics, such as absence of ER expression, that occurs in African Americans and Hispanics and in white European women with a different genetic background.”
“The ESCAPE study (European Study of Cohorts for Air Pollution Effects) investigates long-term effects of exposure to air pollution on human health in Europe. This paper documents the spatial variation of measured NO2 and NOx concentrations between and within 36 ESCAPE study areas across Europe.\n\nIn all study areas NO2 and NOx were measured using standardized methods between October 2008 and April 2011.

On average, 41 sites were selected per study area, including regional and urban background as well as street sites. The measurements were conducted in three different seasons, using Ogawa badges. Average concentrations for each site were calculated HIF-1 activation after adjustment for temporal variation using data obtained from a routine monitor background site.\n\nSubstantial spatial variability was found in NO2 and NOx concentrations between and within study areas; 40% of the overall NO2 variance was attributable to the variability between study areas and 60% to variability within study areas. The corresponding values for NOx were 30% and 70%. The within-area spatial variability was mostly determined by differences between street and urban background concentrations. The street/urban background concentration ratio for NO2 varied between 1.09 and 3.16 across areas. The highest median concentrations were observed in Southern Europe, the lowest in Northern Europe.\n\nIn conclusion, we found significant contrasts in annual average NO2 and NOx concentrations between and especially within 36 study areas across Europe.

0 percent), but lower among those with single sexual partners

0 percent), but lower among those with single sexual partners selleck compound (15.0 percent).

A history of needle injuries, jaundice and injections from quacks were statistically significant when these risks were combined with a sexual risk for hepatitis B virus infection (p-value is less than 0.05).\n\nConclusion: Sexual transmission of hepatitis B was not found to be an important factor. Preventive strategies should include universal hepatitis B vaccination and discouraging the indiscriminate use of sharp objects and unauthorised medical practices.”
“The etiology of osteochondritis dissecans (OCD) of the capitellum is unknown but has generally been attributed to repetitive microtrauma or ischemia. We present a case report of a handball player with OCD of the capitellum. Preoperatively, he complained of elbow pain. CT imaging showed the injury. This patient was treated with mosaicplasty harvested from the lateral femoral condyle. He returned to his full former sports activities within 6 months of surgery. The continuity of the cartilage layer between the osteochondral graft and the capitellum was shown JQEZ5 on CT arthrogram images at 12 months after surgery. We believe that mosaicplasty gives successful results with end-stage OCD of the capitellum. (C) 2012 Published by Elsevier Masson

“There are hundreds of biological resource centers (BRCS) around tire world, holding many little-studied microorganisms. The proportion of bacterial strains that is well represented in the sequence and literature databases may be as low as 1%. This body of unexplored diversity represents an untapped source of useful strains and derived products. However, a modicum of phenotypic data is available for almost all the bacterial strains held by BRCS around the world. It is at the phenotypic level that our knowledge of the well-studied strains of bacteria and the many yet to be studied strains intersect. Thus, the might leverage the phenotypic data from the data-poor bacteria with the omics data front the data-rich bacteria, using our knowledge of their evolutionary relationships,

to map the metabolic networks of the little-known bacteria. This systems biology-based approach is a new way to Sapitinib explore the diversity harbored in BRCS.”
“Sensitivity and elasticity analysis of population projection matrices (PPMs) are established tools in the analysis of structured populations, allowing comparison of the contributions made by different demographic rates to population growth. In some commonly used structures of PPM, however, there are mathematically inevitable patterns in the relative sensitivity and elasticity of certain demographic rates. We take a simulation approach to investigate these mathematical constraints for a range of PPM models. Our results challenge some previously proposed constraints on sensitivity and elasticity. We also identify constraints beyond those that have already been proven mathematically and promote them as candidates for future mathematical proof.