Dosimetric evaluation of LINAC-based single-isocenter multi-target multi-fraction stereotactic radiosurgery with more than 20 targets: comparing MME, HyperArc, and RapidArc

BACKGROUND

To compare the dosimetric quality of three widely used techniques for LINAC-based single-isocenter multi-target multi-fraction stereotactic radiosurgery (fSRS) with more than 20 targets: dynamic conformal arc (DCA) in BrainLAB Multiple Metastases Elements (MME) module and volumetric modulated arc therapy (VMAT) using RapidArc (RA) and HyperArc (HA) in Varian Eclipse.

METHODS

Ten patients who received single-isocenter fSRS with 20-37 targets were retrospectively replanned using MME, RA, and HA. Various dosimetric parameters, such as conformity index (CI), Paddick CI, gradient index (GI), normal brain dose exposures, maximum organ-at-risk (OAR) doses, and beam-on times were extracted and compared among the three techniques. Wilcoxon signed-rank test was used for statistical analysis.

RESULTS

All plans achieved the prescribed dose coverage goal of at least 95% of the planning target volume (PTV). HA plans showed superior conformity compared to RA and MME plans. MME plans showed superior GI compared to RA and HA plans. RA plans resulted in significantly higher low and intermediate dose exposure to normal brain compared to HA and MME plans, especially for lower doses of ≥ 8Gy and ≥ 5Gy. No significant differences were observed in the maximum dose to OARs among the three techniques. The beam-on time of MME plans was about two times longer than RA and HA plans.

CONCLUSIONS

HA plans achieved the best conformity, while MME plans achieved the best dose fall-off for LINAC-based single-isocenter multi-target multi-fraction SRS with more than 20 targets. The choice of the optimal technique should consider the trade-offs between dosimetric quality, beam-on time, and planning effort.

Impact of Limited Enhanced Recovery Pathway for Cardiac Surgery: A Single-Institution Experience

OBJECTIVES

Enhanced recovery pathway (ERP) refers to extensive multidisciplinary, evidence-based pathways used to facilitate recovery after surgery. The authors assessed the impact that limited ERP protocols had on outcomes in patients undergoing cardiac surgery at their institution.

DESIGN

A retrospective cohort study.

SETTING

This study was a single-institution study conducted at a university hospital.

PARTICIPANTS

Patients undergoing open adult cardiac surgery.

INTERVENTIONS

Enhanced recovery pathways limited to preoperative, intraoperative, and postoperative management of pain, atrial fibrillation prevention, and nutrition optimization were implemented.

MEASUREMENTS AND MAIN RESULTS

A total of 1,058 patients were included in this study. There were 374 patients in each pre- and post-ERP cohort after propensity matching, with no significant baseline differences between the 2 cohorts. Compared to the matched patients in the pre-ERP group, patients in the post-ERP group had decreased total ventilation hours (6.8 v 7.8, p = 0.006), less use of postoperative opioid analgesics as determined by total morphine milligram equivalent (32.5 v 47.5, p < 0.001), and a decreased rate of postoperative atrial fibrillation (23.3% v 30.5%, p = 0.032). Post-ERP patients also experienced less subjective pain and postoperative nausea and drowsiness as compared to their matched pre-ERP cohorts.

CONCLUSIONS

Limited ERP implementation resulted in significantly improved perioperative outcomes. Patients additionally experienced less postoperative pain despite decreased opioid use. Implementation of ERP, even in a limited format, is a promising approach to improving outcomes in patients undergoing cardiac surgery.

Treatment characteristics of chronic low back pain patients treated with buprenorphine buccal film or transdermal patch

Aims: Retrospective insurance claims analysis exploring treatment characteristics in chronic low back pain patients prescribed buprenorphine buccal film (Belbuca®) or transdermal patches. Patients and methods: The first buprenorphine prescription (buccal film or transdermal patch) was an index event. Patients were observed over 6 month pre- and post-index periods. Propensity score matching minimized the selection bias. Results: Buccal film patients had a higher buprenorphine daily dose (501.7 vs 270.9 µg; p < 0.001). The patch-to-film switching rate was higher than vice versa (11.5 vs 3.8%; p < 0.001). The buccal film showed a greater reduction in opioid prescriptions (-1.1 vs -0.7; p = 0.012), daily morphine milligram equivalents (-12.6 vs -7.3; p < 0.001) and opioid treatment duration (-13.4 vs -7.6 days; p = 0.022). Conclusion: Buccal film was associated with higher buprenorphine doses and a greater reduction of opioid burden.

Can pain be improved with retention of the posterior cruciate ligament during total knee arthroplasty?

PURPOSE

The purpose of the current study was to determine if differences exist between cruciate-retaining (CR) and posterior-stabilized (PS) implant articulations for total knee arthroplasty (TKA) with regards to early post-operative pain.

METHODS

We retrospectively reviewed patients who underwent primary TKA, with the same TKA implant design, at our institution between January 2018 and July 2021. Patients were stratified based on whether they received a CR or non-constrained PS (PSnC) articulation and propensity score matched in a 1:1 ratio. A sub-analysis matching patient who received a constrained PS implant (PSC) to those undergoing CR TKA and PSnC TKA was also carried out. Opioid dosages were converted to morphine milligram equivalents (MME).

RESULTS

616 patients after CR TKA were matched 1:1 to 616 patients with a PSnC implant. There were no significant differences between demographic variables. There were no statistically significant differences in opioid usage measured by MME on post-operative day (POD) 0 (p = 0.171), POD1 (p = 0.839), POD2 (p = 0.307), or POD3 (p = 0.138); VAS pain scores (p = 0.175); or 90-day readmission rate for pain (p = 0.654). A sub-analysis of CR versus PSC TKA demonstrated no significant differences in opioid usage on POD0 (p = 0.765), POD1 (p = 0.747), POD2 (p = 0.564), POD3 (p = 0.309); VAS pain scores (p = 0.293); and 90-day readmission rate for pain (p > 0.9).

CONCLUSION

Our analysis demonstrated no significant difference in post-operative VAS pain scores and MME usage based on implant. The results suggest that neither the type of articulation or constraint used for primary TKA has a significant impact on immediate post-operative pain and opioid consumption.

LEVEL III EVIDENCE

Retrospective Cohort Study.

Trends of Opioid Usage in Surgical Patients in a Small Community Hospital: Analysis of Patient Data Between 2017 and 2021

Purpose: The purpose of our study was to quantify and analyze the annual opioid usage in surgical patients at Wood County Hospital (WCH) between 2017 and 2021. Methods: In this retrospective study, patient data between 2017 and 2021 was analyzed to determine the oral morphine milligram equivalent (MME) of opioids used in surgical patients at WCH. Annual MME prescribed per admission was compared each year using one-way ANOVA followed by Tukey post hoc test. Similarly, the annual use of intravenous (IV) acetaminophen for surgical patients per admission was also calculated and analyzed using the one-way ANOVA followed by Tukey post hoc test. Results: Compared to the year 2017 (42.0 ± 3.6), a statistically significant decrease in opioid usage per surgical admission (mean±SEM of MME) was observed during the years 2018 (32.6 ± 1.4; P = .04), 2019 (30.4 ± 1.2; P = .01), and 2021 (30.8 ± 1.9; P = .01). An analysis of individual opioid use revealed a trend toward lower fentanyl and hydromorphone usage each year since 2017. A significant decrease in the annual morphine usage (mean±SEM of MME) for surgical patients was observed during both 2020 (14.4 ± 0.9; P = .05) and 2021 (14.0 ± 0.7; P = .05) compared to the year 2017 (22.1 ± 2.4). Finally, compared to the year 2017, a statistically significant decrease (P < .05) in the annual use of oxycodone (MME) and IV acetaminophen (mg) for pain management in surgical patients was observed from 2018 to 2021. Conclusion: Our analysis reveals a significant decrease in opioid usage per surgical admission at WCH over 2017 to 2021 indicating a positive impact of the various opioid stewardship measures implemented at the hospital.

Trends of opioid prescription in cancer patients utilizing telemedicine: a retrospective study

Aim: Prescribing patterns among healthcare practitioners remain a recurring theme of interest in the opioid crisis. This study aims to provide insight on opioid prescribing patterns for cancer pain in telemedicine and in-person encounters during COVID-19. Materials & methods: A retrospective chart review of 1000 encounters (500 telemedicine and 500 in-person) at an academic tertiary care comprehensive cancer center. Results: On average, overall, significantly higher narcotics (in morphine milligram equivalents [MME]) prescribed for patients receiving telemedicine services. In-person encounters had a significantly higher proportion of narcotic (in MME) increases in subsequent visits. Conclusion: Our institution continues to adapt telehealth services as an additional care venue and deeper insight helps mitigate development of maladaptive opioid prescribing patterns.

Rapid Adoption of Telemedicine Increases Opioid Prescribing in Orthopedic Surgery

Background: The COVID-19 pandemic led to health care practitioners utilizing new technologies to deliver health care, including telemedicine. The purpose of this study was to examine the effect of rapidly proliferative use of video visits on opioid prescribing to orthopedic patients at a large academic health system that had existing procedure-specific opioid prescribing guidelines. Methods: This IRB-exempt study examined 651 opioid prescriptions written to patients who had video (visual and audio), telephone (audio only), or in-person encounters at our institution from March 1 to June 1, 2020 and compared them with 963 prescriptions written during the same months in 2019. Prescriptions were converted into daily milligram morphine equivalents (MMEs) to facilitate direct comparison. Chi-square testing was used to compare categorical data, whereas analysis of variance and Mann-Whitney tests were used to compare numerical data between groups. Statistical significance was set at <0.05. Results: Six hundred fifty-one of 1,614 prescriptions analyzed (40.3%) occurred during the pandemic. Patients prescribed opioids during video visits were prescribed 53.3 ± 37 MME, significantly higher than in-person (p = 0.002) or audio visits (p < 0.001) before or during the pandemic. Prepandemic, significantly higher MME were prescribed for in-person versus audio only visits (41.6 ± 89 vs. 30.2 ± 28 MME; p = 0.026); during the pandemic, there was no difference between these groups (p = 0.91). Significantly higher MME were prescribed by Nurse Practitioners and Physician Associates versus MD or DO prescribers for both time periods (51.3 ± 109 vs. 27.9 ± 42 MME; p < 0.001; 42.9 ± 70 vs. 28.2 ± 42 MME; p < 0.001). Conclusion: During crisis and with new technology, we should be vigilant about prescribing of opioid analgesics. Despite well-established protocols, patients received significantly higher MME through video than for other encounter types, including in-person encounters. In addition, significantly higher MME were prescribed by mid-level prescribers compared with DOs or MDs. Institutions should ensure these prescribers are involved during creation of opioid prescribing protocols after orthopedic surgery.

Salviolone protects against high glucose-induced proliferation, oxidative stress, inflammation, and fibrosis of human renal mesangial cells by upregulating membrane metalloendopeptidase expression

As one of complications of diabetes mellitus, diabetic nephropathy is related to renal dysfunction. Membrane metalloendopeptidase (MME) is associated with the pathogenesis of diabetic nephropathy and exerts a protective function in high glucose (HG)-treated podocytes. Salviolone, one of important bioactive components from Salvia miltiorrhiza, possesses an anti-inflammatory activity. However, the roles of salviolone in renal mesangial cell dysfunction under HG condition remain unknown. The targets of salviolone in diabetic nephropathy were predicted by bioinformatics analysis. Relative mRNA level of MME was detected by qPCR in HG-treated human renal mesangial cells (HRMCs). Cell viability was analyzed using CCK-8 assay. Cell proliferation was investigated by EdU staining. Oxidative stress was evaluated by detection of ROS generation and levels of oxidative stress-related biomarkers. The inflammatory cytokines and fibrosis-related biomarkers were examined by ELISA. Our results showed that MME expression was decreased in diabetic nephropathy and HG-treated HRMCs. Salviolone increased MME level in HG-treated HRMCs. Salviolone mitigated HG-induced HRMC proliferation by increasing MME expression. Salviolone attenuated HG-induced ROS generation, MDA level increase, and SOD activity decrease through upregulating MME expression. Moreover, salviolone suppressed HG-induced increase of levels of TNF-α, IL-1β, IL-6, fibronectin, and collagen IV through upregulating MME expression. In conclusion, salviolone attenuates proliferation, oxidative stress, inflammation, and fibrosis in HG-treated HRMCs through upregulating MME expression.

Perceived Efficacy, Reduced Prescription Drug Use, and Minimal Side Effects of Cannabis in Patients with Chronic Orthopedic Pain

Introduction: Although cannabis is widely used for the treatment of chronic pain, most research relies on patient self-report and few studies have objectively quantified its efficacy and side effects. Extant inventories for measuring cannabis use were not designed to capture the medically relevant features of cannabis use, but rather were designed to detect problematic use or cannabis use disorder. Thus, we sought to capture the medically relevant features of cannabis use in a population of patients with orthopedic pain and pair these data with objective measures of pain and prescription drug use. Materials and Methods: In this prospective observational study, orthopedic pain patients were enrolled in Pennsylvania's medical cannabis program by their treating pain management physician, received cannabis education from their physician at the time of certification, and purchased products from state-licensed cannabis retailers. Results: Medical cannabis use was associated with clinical improvements in pain, function, and quality of life with reductions in prescription drug use; 73% either ceased or decreased opioid consumption and 31% discontinued benzodiazepines. Importantly, 52% of patients did not experience intoxication as a side effect of cannabis therapy. Significant clinical benefits of cannabis occurred within 3 months of initiating cannabis therapy and plateaued at the subsequent follow-ups. Conclusions: This work provides a direct relationship between the initiation of cannabis therapy and objectively fewer opioid and benzodiazepine prescriptions. Our work also identifies specific subpopulations of patients for whom cannabis may be most efficacious in reducing opioid consumption, and it highlights the importance of both physician involvement and patient self-titration in symptom management with cannabis.

Evaluation of Individualized Pain Plans for Children With Sickle Cell Disease Admitted for Vaso-occlusive Crisis at Riley Hospital for Children

OBJECTIVE

Vaso-occlusive crisis (VOC) is the most common problem reported by patients with sickle cell disease (SCD). The objective of this study was to evaluate the impact of individualized pain plans in pediatric patients with SCD admitted for VOC.

METHODS

This was a pre- and post-study of patients with SCD admitted to Riley Hospital for Children for VOC from July 1, 2019, through July 1, 2020. The primary outcome was length of inpatient stay for VOC. Secondary outcomes included final pain score, days on scheduled opioids, days on breakthrough opioids, and average morphine milligram equivalents (MME) used per day.

RESULTS

Nine patients were included. The mean age was 16 years (range, 10-20 years). Key clinical findings were decreases in median [IQR] for final pain scores (7 [4.5-9] vs 6 [2.5-8], p = 0.396) and number of days of breakthrough opioid use (5 [3-8] vs 4 [2.5-5.5], p = 0.233). Following implementation of an individualized pain plan, there was an increase in median average MME per day (65.94 [53.1-97.7] vs 82.85 [41-114.3], p = 0.844). Median length of stay and days on scheduled opioids remained the same.

CONCLUSIONS

This study demonstrated that use of individualized pain plans in a small population of patients with SCD might result in decreased pain scores and decreased days on breakthrough opioids.

A Novel Mutation of the Membrane Metallo-Endopeptidase Gene Related to Late-Onset Hereditary Polyneuropathy: Case Report and Review of the Literature

The advent of next generation sequencing has revolutionized diagnostic approaches to hereditary polyneuropathies. Recently, mutations on the membrane metallo-endopeptidase (MME) gene, encoding neprilysin, have been related to the development of late-onset Charcot-Marie-Tooth disease type 2 (CMT2). Here, we report the first Greek patient presenting with a slowly progressive late-onset axonal polyneuropathy and a novel, likely pathogenic, heterozygous variant in the MME gene. In addition, we have performed a systematic review of all published case reports of patients with MME mutations. The results of the studies show that MME variants can be inherited as both fully penetrant autosomal-recessive and incompletely penetrant autosomal-dominant traits. A number of heterozygous variants characterized as incompletely penetrant impose an increased risk of developing a CMT2-like phenotype late in life, identical to the case study described here. Greater mutation numbers in different populations and mutation-specific functional studies will be essential to identify the pathogenicity and inheritance of more MME variants.

Prevalence of Opioid-Induced Adrenal Insufficiency in Patients Taking Chronic Opioids

CONTEXT

Chronic opioid use may lead to adrenal insufficiency because of central suppression of the hypothalamic-pituitary-adrenal axis. However, the prevalence of opioid-induced adrenal insufficiency (OIAI) is unclear.

OBJECTIVE

To determine the prevalence of OIAI and to identify predictors for the development of OIAI in patients taking opioids for chronic pain.

DESIGN

Cross-sectional study, 2016-2018.

SETTING

Referral center.

PATIENTS

Adult patients taking chronic opioids admitted to the Pain Rehabilitation Center.

MAIN OUTCOME MEASURE

Diagnosis of OIAI was considered if positive case detection (cortisol < 10 mcg/dL, ACTH < 15 pg/mL, and dehydroepiandrosterone sulfate < 25 mcg/dL), and confirmed after endocrine evaluation. Daily morphine milligram equivalent (MME) was calculated.

RESULTS

In 102 patients (median age, 53 years [range, 22-83], 67% women), median daily MME was 60 mg (3-840), and median opioid therapy duration was 60 months (3-360). Abnormal case detection testing was found in 11 (10.8%) patients, and diagnosis of OIAI was made in 9 (9%). Patients with OIAI were on a higher daily MME (median, 140 [20-392] mg vs 57 [3-840] mg, P = 0.1), and demonstrated a 4 times higher cumulative opioid exposure (median of 13,440 vs 3120 mg*months, P = 0.03). No patient taking <MME of 20 mg/day developed OIAI (sensitivity of 100% for MME > 20 mg); however, specificity of MME cutoff >20 mg was only 19%. After opioid discontinuation, 6/7 patients recovered adrenal function.

CONCLUSION

The prevalence of OIAI was 9%, with MME cumulative exposure being the only predictor for OIAI development. Patients on MME of 20 mg/day and above should be monitored for OIAI.

Maternal Overweight Downregulates MME (Neprilysin) in Feto-Placental Endothelial Cells and in Cord Blood

Maternal overweight in pregnancy alters the metabolic environment and generates chronic low-grade inflammation. This affects fetal development and programs the offspring’s health for developing cardiovascular and metabolic disease later in life. MME (membrane-metalloendopeptidase, neprilysin) cleaves various peptides regulating vascular tone. Endothelial cells express membrane-bound and soluble MME. In adults, the metabolic environment of overweight and obesity upregulates endothelial and circulating MME. We here hypothesized that maternal overweight increases MME in the feto-placental endothelium. We used primary feto-placental endothelial cells (fpEC) isolated from placentas after normal vs. overweight pregnancies and determined MME mRNA, protein, and release. Additionally, soluble cord blood MME was analyzed. The effect of oxygen and tumor necrosis factor α (TNFα) on MME protein in fpEC was investigated in vitro. Maternal overweight reduced MME mRNA (−39.9%, p < 0.05), protein (−42.5%, p = 0.02), and MME release from fpEC (−64.7%, p = 0.02). Both cellular and released MME protein negatively correlated with maternal pre-pregnancy BMI. Similarly, cord blood MME was negatively associated with pre-pregnancy BMI (r = −0.42, p = 0.02). However, hypoxia and TNFα, potential negative regulators of MME expression, did not affect MME protein. Reduction of MME protein in fpEC and in cord blood may alter the balance of vasoactive peptides. Our study highlights the fetal susceptibility to maternal metabolism and inflammatory state.

Associations of Opioid Prescriptions with Death and Hospitalization across the Spectrum of Estimated GFR

BACKGROUND AND OBJECTIVES

Most opioids undergo kidney excretion. The goal of this study was to evaluate opioid-associated risks of death and hospitalization across the range of eGFR.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The study population included adult primary care patients in Geisinger Health (Danville, PA) between 2008 and 2017. People receiving their first opioid prescription were propensity matched to people receiving NSAIDS (and, in sensitivity analysis, gabapentinoids) and the risk of death and hospitalization were compared, classifying opioid medication exposure as time-varying daily oral morphine milligram equivalents (MMEs) across time-varying eGFR.

RESULTS

The propensity-matched cohort included 46,246 patients prescribed either opioids or NSAIDs between 2008 and 2017 (mean [SD] age, 54 [16] years; 56% female; 3% of black race). Prescriptions for 1-59 and ≥60 MMEs were associated with higher risk of death (HR, 1.70; 95% CI, 1.41 to 2.05 for 1-59 MMEs; HR, 2.25; 95% CI, 1.82 to 2.79 for ≥60 MMEs) and hospitalization (HR, 1.38; 95% CI, 1.30 to 1.46 for 1-59 MMEs; HR, 1.68; 95% CI, 1.56 to 1.81 for ≥60 MMEs) compared with NSAID prescriptions, when evaluated at eGFR 80 ml/min per 1.73 m². The relative risk of death associated with ≥60 MMEs was higher at lower GFR (e.g., eGFR, 40 ml/min per 1.73 m²; HR, 3.94; 95% CI, 2.70 to 5.75; P for interaction, 0.01). When gabapentinoids were used as the comparison medication, only ≥60 MMEs were significantly associated with higher risk of death (HR, 2.72; 95% CI, 1.71 to 4.34), although both 1-59 and ≥60 MMEs were associated with risk of hospitalization (HR, 1.22; 95% CI, 1.04 to 1.43 for 1-59 MMEs; HR, 1.54; 95% CI, 1.28 to 1.86 for ≥60 MMEs).

CONCLUSIONS

The receipt of prescription opioids was associated with a higher risk of death and hospitalization compared with other pain medications, particularly with higher doses and at lower eGFR.

Membrane metallo-endopeptidase is dispensable for repair after nerve injury

Membrane metallo-endopeptidase (MME), also known as neprilysin (NEP), has been of interest for its role in neurodegeneration and pain due to its ability to degrade β-amyloid and substance-P, respectively. In addition to its role in the central nervous system, MME has been reported to be expressed in the peripheral system, specifically in the inner and outer border of myelinating fibers, in the Schmidt-Lantermann cleft and in the paranodes. Recently, mutations of this gene have been associated with Charcot-Marie-Tooth Type 2 (CMT2). Peripheral nerve morphometry in mice lacking MME previously showed minor abnormalities in aged animals in comparison to CMT2 patients. We found that MME expression was dysregulated after nerve injury in a Neuregulin-1 dependent fashion. We therefore explored the hypothesis that MME may have a role in remyelination. In the naïve state in adulthood we did not find any impairment in myelination in MME KO mice. After nerve injury the morphological outcome in MME KO mice was indistinguishable from WT littermates in terms of axon regeneration and remyelination. We did not find any difference in functional motor recovery. There was a significant difference in sensory function, with MME KO mice starting to recover response to mechanical stimuli earlier than WT. The epidermal reinnnervation, however, was unchanged and this altered sensitivity may relate to its known function in cleaving the peptide substance-P, known to sensitise nociceptors. In conclusion, although MME expression is dysregulated after nerve injury in a NRG1-dependent manner this gene is dispensable for axon regeneration and remyelination after injury.

The Impact of Increased Hydrocodone Regulation on Opioid Prescribing in an Urban Safety-Net Health Care System

BACKGROUND

Hydrocodone-combination analgesics were changed from Schedule III to Schedule II to discourage the prescribing of these analgesics. Our primary aim was to explore the effect of hydrocodone rescheduling on opioid prescribing within an urban safety-net health care system.

METHODS AND DESIGN

Data were extracted from electronic records of ambulatory patients (N = 82,432 patients) prescribed hydrocodone-combination, codeine-combination, or tramadol opioid analgesics (N = 200,675 prescriptions) between October 6, 2013 and October 6, 2015. Data analyses modeled predicted probabilities of hydrocodone-combination prescriptions (HCPs). Chronic opioid therapy (COT) for chronic pain (ie, ≥3 opioid prescriptions/12 months) and morphine milligram equivalency (MME) levels were also examined.

RESULTS

The probability of providers writing HCPs decreased significantly from pre- to postrescheduling (0.525 vs 0.158, respectively, P < .0001). However, this coincided with large probability increases in codeine-combination (0.064 vs 0.269) and tramadol prescriptions (0.412 vs 0.573). The probability of HCPs varied across physician specialty (P < .0001), patient diagnoses (P < .0001), COT versus non-COT patients (P < .0001), and patient characteristics (sex, race/ethnicity, and age; P < .05). COT patients received significantly more opioid prescriptions in the postrescheduling period (M = 4.81 vs M = 4.27; P < .0001). Patients on <20 MME/day increased slightly from pre- to postrescheduling (P < .0001).

DISCUSSION

Significant declines in HCPs occurred after rescheduling; however, one third of patients prescribed opioids remained on doses ≥20 MME/day. Codeine- and tramadol-prescription probabilities increased significantly and providers may have an increased perception of safety about these medications. Physicians and health care systems must reduce their overreliance on opioids in treating pain, especially chronic pain, as all opioids incur some level of risk.

The Association of MME microRNA Binding Site Polymorphism with the Risk of Late Onset Alzheimer's Disease in Northern Han Chinese

BACKGROUND

Although β-amyloid (Aβ) degradation has been normally implicated in the pathogenesis of late-onset Alzheimer's disease (LOAD) through cellular biological studies, the genetic studies linking Aβ degradation and LOAD are still scarce. Neprilysin (NEP), one of the most crucial Aβ-degrading enzymes in AD, is the metalloendopeptidase which particularly participates in the monomeric Aβ species degradation. MicroRNAs (miRNAs) exert post-transcriptional dysregulation and their target sequence on the 3' untranslated regions (3'UTR) may be regulated by single nucleotide polymorphisms (SNPs).

OBJECTIVE

To investigate the potential risk of common locus within NEP gene (MME) with LOAD in Northern Han Chinese population.

METHOD

We screened a locus (rs6665) in 3' UTR of NEP gene (MME) which sequence was specially regulated by miRNA-187, and further investigated its possible association with LOAD onset in a large case-control study (984 LOAD patients and 1354 healthy controls) in Northern Han Chinese.

RESULTS

The distribution of rs6665 genotype (P=0.003) and allele A/C (P=0.001) showed significant difference between LOAD and controls (Odds Ratio (OR) =1.255, 95% Confidence Interval (CI) =1.102-1.429). After adjusting for age, gender and Apolipoprotein (ApoE) ε4 status, the minor C allele of rs6665 showed significant association with LOAD in all three genotypic models (Dominant: P=0.003, OR=1.291, 95%CI=1.092-1.526; Recessive: P=0.030, OR =1.425, 95%CI =1.035- 1.961; Additive: P=0.001, OR=1.249,95%CI=1.093-1.427). After stratifying by ApoE ε4 status, rs6665 polymorphism was found to elevate the LOAD risk in ApoE ε4 carriers (P=0.002, OR=1.846, 95%CI=1.264-2.697).

CONCLUSION

Our study firstly confirmed the association of MME miRNA binding site polymorphism with the risk of LOAD. However, the association results warrant further validation.

The role of ACE2, angiotensin-(1-7) and Mas1 receptor axis in glucocorticoid-induced intrauterine growth restriction

BACKGROUND

Plasma and urine levels of the potent vasodilator Ang-(1-7) are elevated in mid and late pregnancy and are correlated with elevated placental angiogenesis, fetal blood flow, and rapid fetal growth. We hypothesized that Ang-(1-7), its receptor (Mas1) and the enzymes involved in Ang-(1-7) production (ACE2 and Membrane metallo-endopeptidase; MME) are down regulated in response to glucocorticoid administration contributing to IUGR.

METHODS

Pregnant female Sprague-Dawley rats were injected with dexamethasone (DEX; 0.4 mg/kg/day) starting from 14 day gestation (dg) till sacrifice at 19 or 21 dg while control groups were injected with saline (n = 6/group). The gene and protein expression of ACE2, MME, Ang-(1-7) and Mas1 receptor in the placental labyrinth (LZ) and basal zones (BZ) were studied.

RESULTS

DEX administration caused a reduction in LZ weight at 19 and 21 dg (p < 0.001). IUGR, as shown by decreased fetal weights, was evident in DEX treated rats at 21 dg (p < 0.01). ACE2 gene expression was elevated in the LZ of control placentas at 21 dg (p < 0.01) compared to 19 dg and DEX prevented this rise at both gene (p < 0.01) and protein levels (p < 0.05). In addition, Ang-(1-7) protein expression in LZ was significantly reduced in DEX treated rats at 21 dg (p < 0.05). On the other hand, Mas1 and MME were upregulated in LZ at 21 dg in both groups (p < 0.05 and p < 0.001, respectively).

CONCLUSION

The results of this study indicate that a reduced expression of ACE2 and Ang-(1-7) in the placenta by DEX treatment may be responsible for IUGR and consequent disease programming later in life.

CD10 expression is enhanced by Twist1 and associated with poor prognosis in esophageal squamous cell carcinoma with facilitating tumorigenicity in vitro and in vivo

CD10 expression was identified as a contributor to cancer progression in several cancers; however, the exact biological significance and mechanism of CD10 expression remains unclear. In addition, CD10 expression in esophageal squamous cell carcinoma (ESCC) has not been studied. We investigated the relationship between CD10 and Twist1. Furthermore, we examined the effect of CD10 on tumorigenicity using in vivo and in vitro systems as well as establishing the clinical significance of CD10 expression in ESCC using large clinical samples. CD10 expression was upregulated by Twist1 and there was a strong correlation between mRNA and protein expression. Twist1 can specifically upregulate CD10 at the transcriptional level via an interaction with the promoter region of CD10 and the proximal E-box CAGGTG in the CD10 promoter was identified as a binding site for Twist1. CD10 is frequently expressed in ESCC cell lines and silencing CD10 suppresses migration/invasion and anchorage-independent tumor growth of ESCC cells. Knockdown of CD10 inhibits the growth of ESCC xenograft in nude mice, suggesting that CD10 plays a role in enhancing the tumorigenesis of ESCC. From among 153 ESCC samples, 46 (30.0%) showed varying degrees of CD10 expression in cancer cells. In addition, stromal fibroblasts also showed varying amounts of CD10 expression in 92 (60.9%) tumor samples. CD10 overexpression in cancer cells as well as in stromal fibroblasts was an independent poor prognostic factor in both overall survival and disease-free survival. CD10 could be a promising target for the treatment of ESCC.

The clinical spectrum of microcystic macular edema

PURPOSE

Microcystic macular edema (MME), originally described in British literature as microcystic macular oedema (MMO), defines microcysts in the inner nuclear layer (INL) of the retina. Microcystic macular edema was described in multiple sclerosis (MS), but can be found in numerous disorders. The presence of MME has important prognostic and therapeutic implications; however, the differential diagnosis is unknown. This study aimed to describe the clinical spectrum of MME.

METHODS

A single-center, retrospective cohort study. A bootstrap analysis was performed to reduce the 5865 patients (22,376 scans), who had undergone OCT imaging between January 2010 and February 2013, to a representative dataset. The presence of MME was rated by independent observers.

RESULTS

The dataset consisted of 1368 patients (mean age 62, range, 4-101 years), 2589 eyes and 6449 scans. Microcystic macular edema was present in 133/1303 (10%) of patients and 0/65 (0%) of healthy controls. The interrater agreement for detecting MME was substantial (kappa 0.6) and could be further improved after refining the criteria (kappa 0.8). The clinical spectrum included age-related macular degeneration, epiretinal membranes, postoperative lesions, diabetic retinopathy, vascular occlusion, MS (with/without optic neuritis), optic neuropathy, central serous chorioretinopathy, medication, and miscellaneous causes. The longitudinal pattern of MME was transient (84%) or static. Microcystic macular edema could be associated with an increase or decrease in INL thickness and was predominantly located nasally (48%) and/or temporally (50%).

CONCLUSIONS

This study substantially widened the clinical spectrum of MME. Diagnostic criteria were refined and validated. The associated phenotype may imply Müller cell dysfunction within the watershed zone. The longitudinal data and evidence from previous studies suggest follow-up of these patients and their visual function.

Genetic variation in MME in relation to neprilysin protein and enzyme activity, Aβ levels, and Alzheimer's disease risk

Neprilysin (NEP), also known as membrane metalloendopeptidase (MME), is considered amongst the most important β-amyloid (Aβ)-degrading enzymes with regard to prevention of Alzheimer's disease (AD) pathology. Variation in the NEP gene (MME) has been suggested as a risk factor for AD. We conducted a genetic association study of 7MME SNPs - rs1836914, rs989692, rs9827586, rs6797911, rs61760379, rs3736187, rs701109 - with respect to AD risk in a cohort of 1057 probable and confirmed AD cases and 424 age-matched non-demented controls from the United Kingdom, Italy and Sweden. We also examined the association of these MME SNPs with NEP protein level and enzyme activity, and on biochemical measures of Aβ accumulation in frontal cortex - levels of total soluble Aβ, oligomeric Aβ(1-42), and guanidine-extractable (insoluble) Aβ - in a sub-group of AD and control cases with post-mortem brain tissue. On multivariate logistic regression analysis one of the MME variants (rs6797911) was associated with AD risk (P = 0.00052, Odds Ratio (O.R. = 1.40, 95% confidence interval (1.16-1.70)). None of the SNPs had any association with Aβ levels; however, rs9827586 was significantly associated with NEP protein level (p=0.014) and enzyme activity (p=0.006). Association was also found between rs701109 and NEP protein level (p=0.026) and a marginally non-significant association was found for rs989692 (p=0.055). These data suggest that MME variation may be associated with AD risk but we have not found evidence that this is mediated through modification of NEP protein level or activity.

Evaluation of neprilysin sequence variation in relation to CSF β-Amyloid levels and Alzheimer disease risk

Neprilysin (NEP) is a principal peptidase involved in the degradation of β-amyloid (Aβ), and as such its encoding gene (MME) has been the target of numerous genetic association studies on Alzheimer disease. Here, in order to attempt replication of previous findings we have investigated several single nucleotide polymorphisms (SNPs) that have been claimed to be associated with AD. A key feature of the present study is the complementary investigation of both AD risk and quantitative measures of AD severity, including cerebrospinal (CSF) fluid levels of AP1-42. In contrast to the effects of APOE, none of these measures are detectably influenced by genetic polymorphism in the MME region. We thus, fail to find support for previous results suggesting that MME impacts AD.