Millennial-scale variability of the Antarctic ice sheet during the early Miocene.

Millennial-scale ice sheet variability (1-15 kyr periods) is well documented in the Quaternary, providing insight into critical atmosphere-ocean-cryosphere interactions that can inform the mechanism and pace of future climate change. Ice sheet variability at similar frequencies is comparatively less known and understood prior to the Quaternary during times, where higher atmospheric pCO2 and warmer climates prevailed, and continental-scale ice sheets were largely restricted to Antarctica. In this study, we evaluate a high-resolution clast abundance dataset (ice-rafted debris) that captures East Antarctic ice sheet variability in the western Ross Sea during the early Miocene. This dataset is derived from a 100 m-thick mudstone interval in the ANtarctic DRILLing (ANDRILL or AND) core 2A, which preserves a record of precession and eccentricity variability. The sedimentation rates are of appropriate resolution to also characterize the signature of robust, subprecession cyclicity. Strong sub-precession (~10 kyr) cyclicity is observed, with an amplitude modulation in lockstep with eccentricity, indicating a relationship between high-frequency Antarctic ice sheet dynamics and astronomical forcing. Bicoherence analysis indicates that many of the observed millennial-scale cycles (as short as 1.2 kyr) are associated with nonlinear interactions (combination or difference tones) between each other and the Milankovitch cycles. The presence of these cycles during the Miocene reveals the ubiquity of millennial-scale ice sheet variability and sheds light on the interactions between Earth's atmosphere, ocean, and ice in climates warmer than the Quaternary.

Development and Evaluation of an Innovative Neurology E-learning Didactic Curriculum for Psychiatry Residents.

OBJECTIVE: This article describes the development, implementation, and piloting of an e-learning neuropsychiatry curriculum for psychiatry residents. The primary outcome of interest was feasibility. Secondary outcomes were interest and confidence caring for patients with neuropsychiatric disorders, and knowledge about neuropsychiatry. METHODS: The curriculum was designed utilizing Kern's six-step framework. A ten-module, interactive, primarily vignette-based e-learning curriculum was developed focusing on the neurocognitive exam and neurocognitive disorders. The curriculum was piloted in two psychiatry residencies in Brooklyn, NY (n = 80 residents). The curriculum was evaluated using a survey adapted from the General Practitioner Attitudes and Confidence Scale for Dementia (GPACS-D) and a 24-item neuropsychiatry examination prior to the intervention and 1-month post-intervention. Qualitative feedback was acquired through four open-ended items in the post-curriculum survey, which underwent a thematic analysis. RESULTS: Seventy-eight of eighty residents completed the full curriculum. Three of nine attitude items demonstrated significant differences, with residents feeling less frustrated managing dementia (pre-mean = 2.32, post = 2.68, t(2,59) = 2.00, p = 0.004), less frustrated due to not knowing how to effectively treat dementia (pre-mean = 2.05, post = 2.95, t(2,59) = 6.27, p = 0.000), and demonstrating less interest in pursuing further training in neuropsychiatry (pre-mean = 1.95, post = 2.18, t(2,59) = 1.70, p = 0.047), though still overall showing interest. There was no change in confidence ratings. There was a small but significant improvement in total number of knowledge items answered correctly. CONCLUSIONS: This study demonstrated the feasibility of implementing an e-learning neuropsychiatry curriculum. It also demonstrated an improvement in resident responses to two attitude items and an increase in neuropsychiatry knowledge.

A Novel Pulsed Stimulation Pattern in Spinal Cord Stimulation: Clinical Results and Postulated Mechanisms of Action in the Treatment of Chronic Low Back and Leg Pain.

OBJECTIVES: The aim of this article is to discuss the possible mechanisms of action (MOAs) and results of a pilot study of a novel, anatomically placed, and paresthesia-independent, neurostimulation waveform for the management of chronic intractable pain. MATERIALS AND METHODS: A novel, multilayered pulsed stimulation pattern (PSP) that comprises three temporal layers, a Pulse Pattern layer, Train layer, and Dosage layer, was developed for the treatment of chronic intractable pain. During preliminary development, the utility was evaluated of anatomical PSP (aPSP) in human subjects with chronic intractable pain of the leg(s) and/or low back, compared with that of traditional spinal cord stimulation (T-SCS) and physiological PSP. The scientific theory and testing presented in this article provide the preliminary justification for the potential MOAs by which PSP may operate. RESULTS: During the pilot study, aPSP (n = 31) yielded a greater decrease in both back and leg pain than did T-SCS (back: -60% vs -46%; legs: -63% vs -43%). In addition, aPSP yielded higher responder rates for both back and leg pain than did T-SCS (61% vs 48% and 78% vs 50%, respectively). DISCUSSION: The novel, multilayered approach of PSP may provide multimechanistic therapeutic relief through preferential fiber activation in the dorsal column, optimization of the neural onset response, and use of both the medial and lateral pathway through the thalamic nuclei. The results of the pilot study presented here suggest a robust responder rate, with several subjects (five subjects with back pain and three subjects with leg pain) achieving complete relief from PSP during the acute follow-up period. These clinical findings suggest PSP may provide a multimechanistic, anatomical, and clinically effective management for intractable chronic pain. Because of the limited sample size of clinical data, further testing and long-term clinical assessments are warranted to confirm these preliminary findings.

Fully displaced pediatric supracondylar humerus fractures: Which ones need to go at night?

Background: Challenges remain in determining which displaced supracondylar humerus fractures are safe to postpone surgical treatment until daylight hours. The purpose of this study is to determine which characteristics can be identified to guide the timing of treatment of supracondylar humerus fractures. Methods: 225 completely displaced Gartland extension type 3/4 supracondylar humerus fractures in healthy patients that presented between 6 am and 7 am were identified. Data were collected retrospectively. Data analysis included univariate, multivariable logistic regression and classification and regression tree analysis. Results: 5% (78/225) underwent surgical treatment the night they presented, while 65% (147/225) were treated the next day. Overall complication rate was 6%, with no difference based on timing of surgery. 12% (28/225) presented with a motor nerve injury, while 6% (14/225) a "pink pulseless" extremity. Statistical analysis found the most reliable radiographic predictor to be the maximum displacement on the anterior-posterior or lateral view. Classification and regression tree analysis developed a clinical algorithm; patients with a "pink pulseless" extremity or motor nerve injury were recommended for surgery overnight, while those with an anterior-posterior or lateral view < 25 mm were recommended for surgery the next day. Conclusion: This study provides guidance on the timing of treatment for displaced supracondylar humerus fractures that present overnight. We provide a simple algorithm with three key clinical predictors for timing of treatment: presence of a "pink pulseless" arm, presence of a motor nerve injury, and displacement of any cortex by at least 25 mm (anterior-posterior or lateral view). This provides a step forward to help practitioners make safer evidenced-based timing decisions for their patients. Level of evidence: Prognostic Study, Level II.

8 out of 10 patients do well after surgery for tarsal coalitions: A systematic review on 1284 coalitions.

BACKGROUND: The primary aim was to determine the clinical success rate after treatment for talocalcaneal (TCC) and calcaneonavicular coalitions (CNC). The secondary aim was to evaluate the complication, recurrence and revision rate. METHODS: A search was carried out in MEDLINE, EMBASE and Cochrane Library. Methodological quality was assessed using the Methodological Index for Non-Randomised Studies (MINORS) criteria. The primary outcome was the clinical success rate and was pooled per type of coalition and treatment modality. 95% Confidence Intervals (CI) of the success rates were calculated. Secondary outcomes included complication rates, coalition recurrence rates, revision rates and pain improvement using the Visual Analogue Scale (VAS). A sub-analysis on interposition material was performed. RESULTS: 43 articles comprising of 1284 coalitions were included, with a pooled mean follow-up of 51 months. Methodological quality was fair. The overall pooled success rate for TCCs was 79% (95% CI, 75%-83%). Conservative treatment, open resection and arthroscopic resection of TCCs resulted in success rates of 58% (95% CI, 42%-73%), 80% (95% CI, 76%-84%) and 86% (95% CI, 71%-94%), respectively. CNCs have an overall success rate of 81% (95% CI, 75%-85%), with 100% (95% CI, 34%-100%), 80% (95% CI, 74%-85%) and 100% (95% CI, 65%-100%) for conservative treatment, open resection and arthroscopic resection, respectively. Pooled complication rates of 4% (95% CI, 3%-7%) for TCCs and 6% (95% CI, 4%-11%) for CNCs were found. The success rates of resection with and without interposition material for TCCs were 83% (95% CI, 78%-87%) and 79% (95% CI, 65%-88%), and for CNCs 81% (95% CI, 76%-86%) and 69% (95% CI, 44%-85%), respectively. CONCLUSION: Treatment of tarsal coalitions can be considered good to excellent as well as safe, with an overall clinical success rate of 79% for TCCs and 81% for CNCs. Arthroscopic resection of the coalition appears to be non-inferior to open resection of TCCs and CNCs. LEVEL OF EVIDENCE: Level IV, Systematic Review.

Retrospective study of patterns of vitamin D testing and status at a single institution paediatric orthopaedics and sports clinics.

OBJECTIVES: There has been a recent increase in awareness of the importance of bone health in children treated by paediatric orthopaedic and sports medicine providers. The purpose of this study was to assess our utilisation of 25 hydroxy vitamin D (25(OH)Vit D) testing in the past 10 years, and to evaluate the level of 25(OH)Vit D sufficiency in various populations of patients seen. DESIGN: This is a single site, retrospective medical record review study. SETTING: The study took place at a single large, private, paediatric level 1 trauma teaching hospital in the Northeast USA. PARTICIPANTS: Our internal medical records query system identified all patients who have had 25(OH)Vit D testing in the past 10 years, from 1 January 2009 to 31 December 2018. All patients included were seen on an outpatient basis at our Orthopaedic clinics. INTERVENTIONS: No interventions for strict research, however, eligible patients have had 25(OH)Vit D testing during their standard of care treatment. MAIN OUTCOME MEASURES: The varying number of 25(OH)Vit D testing that occurred over the study time period within Orthopaedic groups, and by Vit D levels as sufficient, insufficient and deficient. 25(OH)Vit D sufficiency was ≥30 ng/mL, insufficiency <30 ng/mL and deficiency were <20 ng/mL. Patients were stratified and analysed. RESULTS: Between 2009 and 2018, there were 4426 patients who had 25(OH)Vit D testing. Vitamin D testing increased significantly (p<0.001) in the past 10 years. 43% of patients had sufficient 25(OH)Vit D levels, 41% had insufficient levels and 15% had deficient levels. CONCLUSION: More frequent testing has led to an increased identification of patients with insufficient and deficient 25(OH)Vit D levels. We found over 50% of patients tested were found to have 25(OH)Vit D levels under 30 ng/mL. There should be an increased awareness of patients with orthopaedic problems who may present with 25(OH) insufficiency.

Frequency of rare, serious donor reactions: International perspective.

BACKGROUND: Severe blood donor adverse events are rare, but due to their rarity studying them can be difficult. To get an accurate estimate of their frequency and rate in the donor population it may be necessary to combine donation data across countries. STUDY DESIGN AND METHODS: International blood collection organizations (BCOs) provided data on rare/severe donor reactions as well as denominator information for their donor populations from 2015 to 2017. Donor reactions were classified using standardized definitions. RESULTS: BCOs from six countries provided reaction data for more than 22 million donations. A total of 480 rare reactions were reported of which 76.7% were imputed as definite and 11% probable. Rates of rare reactions were higher in females and first-time donors. Systemic rare reactions were the most common reaction type, accounting for over three quarters of reactions reported. Of systemic reactions, vasovagal reactions with loss of consciousness and injury or off-site (n = 350) made up the majority and occurred 1.53 per 100,000 donations. For the 22.3% that were localized reactions, the majority of these were cellulitis (n = 71, 0.31 per 100,000 donations) followed by deep venous thrombosis (n = 21, 0.09 per 100,000 donations). CONCLUSION: Pulling together data from multiple BCOs across countries allows for a better understanding of rare reactions, such as vasovagal reaction with injury or cellulitis, and for generating a reliable incidence rate for air embolism or compartment syndrome. However, gaps remain due to missing elements such as unknown donor status or location of reaction.

Fast generation and detection of spatial modes of light using an acousto-optic modulator.

Spatial modes of light provide a high-dimensional space that can be used to encode both classical and quantum information. Current approaches for dynamically generating and measuring these modes are slow, due to the need to reconfigure a high-resolution phase mask such as a spatial light modulator or digital micromirror device. The process of updating the spatial mode of light can be greatly accelerated by multiplexing a set of static phase masks with a fast, image-preserving optical switch, such as an acousto-optic modulator (AOM). We experimentally realize this approach, using a double-pass AOM to generate one of five orbital angular momentum states with a switching rate of up to 500 kHz. We then apply this system to perform fast quantum state tomography of spatial modes of light in a 2-dimensional Hilbert space by projecting the unknown state onto six spatial modes comprising three mutually unbiased bases. We are able to reconstruct arbitrary states in under 1 ms with an average fidelity of 96.9%.

Is ward round participation by clinical pharmacists a valuable use of time and money? A time and motion study.

BACKGROUND: While the benefits of multidisciplinary ward round (WR) participation by clinical pharmacists have been demonstrated, it can be time-consuming. No previous studies have compared the specific benefits of WR participation and other clinical activities. OBJECTIVES: To assess the clinical impact of different clinical pharmacist activities and analyse patterns of practice based on WR involvement and timing and significance of clinical interventions. METHODS: In a prospective, observational time and motion study, clinical pharmacists servicing 6 unmatched specialty areas in a major quaternary public hospital were observed and their activities documented. Pharmacists' self-recorded interventions underwent expert panel assessment for significance and potential cost savings. Workflows and interventions were analysed for the 4 pharmacists involved in WRs ('WR pharmacists') during their time 'on' and 'off' rounds and for 2 pharmacists not involved in WRs ('non-WR pharmacists') using chi-square analyses. RESULTS: During 170 h of observation, 267 clinical interventions (53.9% minor, 40.1% moderate, 6.0% major) were recorded. WR pharmacists spent 24.3% of their time on rounds, and 64.8% of interventions were made during this time (intervention rates: 4.5/hour on WR vs. 0.8/hour off WR vs. 1.3/hour for non-WR pharmacists). Differences in WR and non-WR pharmacists' workflows were observed, although there was no difference in time spent on clinical/patient-centred activities (p = 0.70). WR involvement was associated with significantly quicker interventions (p < 0.001). All major interventions were made by WR pharmacists; 80% were made on rounds. Major interventions were estimated to have decreased lengths of stay, intensive care requirements and procedure costs. CONCLUSIONS: Clinical pharmacists focussed on patient-centred activities, regardless of WR involvement. Notwithstanding differences in the WR and non-WR specialty areas, WR participation was associated with more significant and timely interventions and potential cost savings. Coupled with the subjective benefits of WR participation observed, these findings support the potential value of clinical pharmacist WR participation.

A Low-Cost Mechanical Stretching Device for Uniaxial Strain of Cells: A Platform for Pedagogy in Mechanobiology.

Mechanical cues including stretch, compression, and shear stress play a critical role in regulating the behavior of many cell types, particularly those that experience substantial mechanical stress within tissues. Devices that impart mechanical stimulation to cells in vitro have been instrumental in helping to develop a better understanding of how cells respond to mechanical forces. However, these devices often have constraints, such as cost and limited functional capabilities, that restrict their use in research or educational environments. Here, we describe a low-cost method to fabricate a uniaxial cell stretcher that would enable widespread use and facilitate engineering design and mechanobiology education for undergraduate students. The device is capable of producing consistent and reliable strain profiles through the use of a servomotor, gear, and gear rack system. The servomotor can be programmed to output various waveforms at specific frequencies and stretch amplitudes by controlling the degree of rotation, speed, and acceleration of the servogear. In addition, the stretchable membranes are easy to fabricate and can be customized, allowing for greater flexibility in culture well size. We used the custom-built stretching device to uniaxially strain macrophages and cardiomyocytes, and found that both cell types displayed functional and cell shape changes that were consistent with the previous studies using commercially available systems. Overall, this uniaxial cell stretcher provides a more cost-effective alternative to study the effects of mechanical stretch on cells, and can therefore, be widely used in research and educational environments to broaden the study and pedagogy of cell mechanobiology.

Discovery of Stromal Regulatory Networks that Suppress Ras-Sensitized Epithelial Cell Proliferation.

Mesodermal cells signal to neighboring epithelial cells to modulate their proliferation in both normal and disease states. We adapted a Caenorhabditis elegans organogenesis model to enable a genome-wide mesodermal-specific RNAi screen and discovered 39 factors in mesodermal cells that suppress the proliferation of adjacent Ras pathway-sensitized epithelial cells. These candidates encode components of protein complexes and signaling pathways that converge on the control of chromatin dynamics, cytoplasmic polyadenylation, and translation. Stromal fibroblast-specific deletion of mouse orthologs of several candidates resulted in the hyper-proliferation of mammary gland epithelium. Furthermore, a 33-gene signature of human orthologs was selectively enriched in the tumor stroma of breast cancer patients, and depletion of these factors from normal human breast fibroblasts increased proliferation of co-cultured breast cancer cells. This cross-species approach identified unanticipated regulatory networks in mesodermal cells with growth-suppressive function, exposing the conserved and selective nature of mesodermal-epithelial communication in development and cancer.

Integrin-linked kinase as a novel molecular switch of the IL-6-NF-κB signaling loop in breast cancer.

Substantial evidence has clearly demonstrated the role of the IL-6-NF-κB signaling loop in promoting aggressive phenotypes in breast cancer. However, the exact mechanism by which this inflammatory loop is regulated remains to be defined. Here, we report that integrin-linked kinase (ILK) acts as a molecular switch for this feedback loop. Specifically, we show that IL-6 induces ILK expression via E2F1 upregulation, which, in turn, activates NF-κB signaling to facilitate IL-6 production. shRNA-mediated knockdown or pharmacological inhibition of ILK disrupted this IL-6-NF-κB signaling loop, and blocked IL-6-induced cancer stem cells in vitro and estrogen-independent tumor growth in vivo Together, these findings establish ILK as an intermediary effector of the IL-6-NF-κB feedback loop and a promising therapeutic target for breast cancer.

A New Player in the Spermiogenesis Pathway of Caenorhabditis elegans.

Precise timing of sperm activation ensures the greatest likelihood of fertilization. Precision in Caenorhabditis elegans sperm activation is ensured by external signaling, which induces the spherical spermatid to reorganize and extend a pseudopod for motility. Spermatid activation, also called spermiogenesis, is prevented from occurring prematurely by the activity of SPE-6 and perhaps other proteins, termed "the brake model." Here, we identify the spe-47 gene from the hc198 mutation that causes premature spermiogenesis. The mutation was isolated in a suppressor screen of spe-27(it132ts), which normally renders worms sterile, due to defective transduction of the activation signal. In a spe-27(+) background, spe-47(hc198) causes a temperature-sensitive reduction of fertility, and in addition to premature spermiogenesis, many mutant sperm fail to activate altogether. The hc198 mutation is semidominant, inducing a more severe loss of fertility than do null alleles generated by CRISPR-associated protein 9 (Cas9) technology. The hc198 mutation affects an major sperm protein (MSP) domain, altering a conserved amino acid residue in a ß-strand that mediates MSP-MSP dimerization. Both N- and C-terminal SPE-47 reporters associate with the forming fibrous body (FB)-membranous organelle, a specialized sperm organelle that packages MSP and other components during spermatogenesis. Once the FB is fully formed, the SPE-47 reporters dissociate and disappear. SPE-47 reporter localization is not altered by either the hc198 mutation or a C-terminal truncation deleting the MSP domain. The disappearance of SPE-47 reporters prior to the formation of spermatids requires a reevaluation of the brake model for prevention of premature spermatid activation.

Function of Integrin-Linked Kinase in Modulating the Stemness of IL-6-Abundant Breast Cancer Cells by Regulating γ-Secretase-Mediated Notch1 Activation in Caveolae.

Interleukin-6 (IL-6) and Notch signaling are important regulators of breast cancer stem cells (CSCs), which drive the malignant phenotype through self-renewal, differentiation, and development of therapeutic resistance. We investigated the role of integrin-linked kinase (ILK) in regulating IL-6-driven Notch1 activation and the ability to target breast CSCs through ILK inhibition. Ectopic expression/short hairpin RNA-mediated knockdown of ILK, pharmacological inhibition of ILK with the small molecule T315, Western blot analysis, immunofluorescence, and luciferase reporter assays were used to evaluate the regulation of IL-6-driven Notch1 activation by ILK in IL-6-producing triple-negative breast cancer cell lines (MDA-MB-231, SUM-159) and in MCF-7 and MCF-7(IL-6) cells. The effects of ILK on γ-secretase complex assembly and cellular localization were determined by immunofluorescence, Western blots of membrane fractions, and immunoprecipitation. In vivo effects of T315-induced ILK inhibition on CSCs in SUM-159 xenograft models were assessed by mammosphere assays, flow cytometry, and tumorigenicity assays. Results show that the genetic knockdown or pharmacological inhibition of ILK suppressed Notch1 activation and the abundance of the γ-secretase components presenilin-1, nicastrin, and presenilin enhancer 2 at the posttranscriptional level via inhibition of caveolin-1-dependent membrane assembly of the γ-secretase complex. Accordingly, knockdown of ILK inhibited breast CSC-like properties in vitro and the breast CSC subpopulation in vivo in xenograft tumor models. Based on these findings, we propose a novel function of ILK in regulating γ-secretase-mediated Notch1 activation, which suggests the targeting of ILK as a therapeutic approach to suppress IL-6-induced breast CSCs.

SPE-8, a protein-tyrosine kinase, localizes to the spermatid cell membrane through interaction with other members of the SPE-8 group spermatid activation signaling pathway in C. elegans.

BACKGROUND: The SPE-8 group gene products transduce the signal for spermatid activation initiated by extracellular zinc in C. elegans. Mutations in the spe-8 group genes result in hermaphrodite-derived spermatids that cannot activate to crawling spermatozoa, although spermatids from mutant males activate through a pathway induced by extracellular TRY-5 protease present in male seminal fluid. RESULTS: Here, we identify SPE-8 as a member of a large family of sperm-expressed non-receptor-like protein-tyrosine kinases. A rescuing SPE-8::GFP translational fusion reporter localizes to the plasma membrane in all spermatogenic cells from the primary spermatocyte stage through spermatids. Once spermatids become activated to spermatozoa, the reporter moves from the plasma membrane to the cytoplasm. Mutations in the spe-8 group genes spe-12, spe-19, and spe-27 disrupt localization of the reporter to the plasma membrane, while localization appears near normal in a spe-29 mutant background. CONCLUSIONS: These results suggest that the SPE-8 group proteins form a functional complex localized at the plasma membrane, and that SPE-8 is correctly positioned only when all members of the SPE-8 group are present, with the possible exception of SPE-29. Further, SPE-8 is released from the membrane when the activation signal is transduced into the spermatid.

Determination of pesticide residues in cannabis smoke.

The present study was conducted in order to quantify to what extent cannabis consumers may be exposed to pesticide and other chemical residues through inhaled mainstream cannabis smoke. Three different smoking devices were evaluated in order to provide a generalized data set representative of pesticide exposures possible for medical cannabis users. Three different pesticides, bifenthrin, diazinon, and permethrin, along with the plant growth regulator paclobutrazol, which are readily available to cultivators in commercial products, were investigated in the experiment. Smoke generated from the smoking devices was condensed in tandem chilled gas traps and analyzed with gas chromatography-mass spectrometry (GC-MS). Recoveries of residues were as high as 69.5% depending on the device used and the component investigated, suggesting that the potential of pesticide and chemical residue exposures to cannabis users is substantial and may pose a significant toxicological threat in the absence of adequate regulatory frameworks.

UV light B-mediated inhibition of skin catalase activity promotes Gr-1+ CD11b+ myeloid cell expansion.

Skin cancer incidence and mortality are higher in men compared with women, but the causes of this sex discrepancy remain largely unknown. UV light exposure induces cutaneous inflammation and neutralizes cutaneous antioxidants. Gr-1(+)CD11b(+) myeloid cells are heterogeneous bone marrow-derived cells that promote inflammation-associated carcinogenesis. Reduced activity of catalase, an antioxidant present in the skin, has been associated with skin carcinogenesis. We used the outbred, immune-competent Skh-1 hairless mouse model of UVB-induced inflammation and non-melanoma skin cancer to further define sex discrepancies in UVB-induced inflammation. Our results demonstrated that male skin had relatively lower baseline catalase activity, which was inhibited following acute UVB exposure in both sexes. Further analysis revealed that skin catalase activity inversely correlated with splenic Gr-1(+)CD11b(+) myeloid cell percentage. Acute UVB exposure induced Gr-1(+)CD11b(+) myeloid cell skin infiltration, which was inhibited to a greater extent in male mice by topical catalase treatment. In chronic UVB studies, we demonstrated that the percentage of splenic Gr-1(+)CD11b(+) myeloid cells was 55% higher in male tumor-bearing mice compared with their female counterparts. Together, our findings indicate that lower skin catalase activity in male mice may at least in part contribute to increased UVB-induced generation of Gr-1(+)CD11b(+) myeloid cells and subsequent skin carcinogenesis.

Routine surveillance of modular PFC TKA shows increasing failures after 10 years.

BACKGROUND/RATIONALE: A 10-year survivorship of 100% was reported for patients with PFC cruciate-retaining prostheses. Beyond 10 years, we observed additional polyethylene wear likely related to thin liners gamma-irradiated in air and were concerned this wear might predispose to implant construct failure. QUESTIONS/PURPOSES: We therefore determined (1) the functional scores at a minimum of 15 years followup, (2) rates of radiographic failure, (3) overall revision rates, and (4) mode of failure after 10 years and the fate of the revised implants. METHODS: We retrospectively reviewed 75 patients with 101 press-fit condylar posterior cruciate-retaining prostheses. At a minimum followup of 15 years, 35 patients (47 knees) were living and evaluated clinically. No patients were lost to followup. RESULTS: There were no revisions during the first 11 years and six reoperations subsequently were performed in five patients (6% overall rate of revision but 12.8% in patients who survived more than 15 years). Three of six revisions had concerning liner wear at 10 years and all six were revised for polyethylene wear. Polyethylene exchange was performed in four of the five patients who underwent revisions, all of whom were doing well at an average of 7.2 years (range, 4.7-9.1 years) after the revision procedure. CONCLUSIONS: At long-term followup, the overall revision rate remained low (6%). For patients surviving 15 years or more, the rate of revision was 12.8% and all revisions were secondary to aseptic sequelae of polyethylene wear. All revisions occurred more than 10 years after the initial procedures. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Prognostic significance of interleukin-6 single nucleotide polymorphism genotypes in neuroblastoma: rs1800795 (promoter) and rs8192284 (receptor).

PURPOSE: Neuroblastoma is a childhood cancer of the sympathetic nervous system and many patients present with high-risk disease. Risk stratification, based on pathology and tumor-derived biomarkers, has improved prediction of clinical outcomes, but overall survival (OS) rates remain unfavorable and new therapeutic targets are needed. Some studies suggest a link between interleukin (IL)-6 and more aggressive behavior in neuroblastoma tumor cells. Therefore, we examined the impact of two IL-6 single nucleotide polymorphisms (SNP) on neuroblastoma disease progression. EXPERIMENTAL DESIGN: DNA samples from 96 high-risk neuroblastoma patients were screened for two SNP that are known to regulate the serum levels of IL-6 and the soluble IL-6 receptor, rs1800795 and rs8192284, respectively. The genotype for each SNP was determined in a blinded fashion and independent statistical analysis was done to determine SNP-related event-free survival (EFS) and OS rates. RESULTS: The rs1800795 IL-6 promoter SNP is an independent prognostic factor for EFS and OS in high-risk neuroblastoma patients. In contrast, the rs8192284 IL-6 receptor SNP revealed no prognostic value. CONCLUSIONS: The rs1800795 SNP [-174 IL-6 (G > C)] represents a novel and independent prognostic marker for both EFS and OS in high-risk neuroblastoma. Because the rs1800795 SNP [-174 IL-6 (G > C)] has been shown to correlate with production of IL-6, this cytokine may represent a target for development of new therapies in neuroblastoma.

Interleukin-6 is a potent growth factor for ER-alpha-positive human breast cancer.

Bone is the primary anatomical site of breast cancer metastasis, and bone metastasis is associated with increased morbidity and mortality. Mesenchymal stem cells (MSC) are a predominant fibroblast cell population within the bone marrow, and metastatic breast cancer cells that seed within bone would predictably encounter MSC or their soluble factors. Therefore, we examined the impact of primary human MSC on a panel of estrogen receptor-alpha (ERalpha)-positive (MCF-7, T47D, BT474, and ZR-75-1) and ERalpha-negative (MDA-MB-231 and MDA-MB-468) human breast tumor cell lines. All ERalpha-positive breast tumor cell lines displayed low basal activation of signal transducer and activator of transcription 3 (STAT3) until exposed to MSC, which induced chronic phosphorylation of STAT3 on tyrosine-705. Paracrine IL-6 was found to be the principal mediator of STAT3 phosphorylation in coculture studies, and MSC induction of STAT3 phosphorylation was lost when IL-6 was depleted from MSC conditioned media or the IL-6 receptor was blocked on tumor cells. Enhanced tumor cell growth rates were observed in the ERalpha-positive mammary tumor cell line MCF-7 after paracrine and autocrine IL-6 exposure, where MCF-7 growth rates were enhanced by >2-fold when cocultured with MSC in vitro and even more pronounced in vivo with autocrine IL-6 production.