Microbial interactions with phosphorus containing glasses representative of vitrified radioactive waste

The presence of phosphorus in borosilicate glass (at 0.1 - 1.3 mol% P2O5) and in iron-phosphate glass (at 53 mol% P2O5) stimulated the growth and metabolic activity of anaerobic bacteria in model systems. Dissolution of these phosphorus containing glasses was either inhibited or accelerated by microbial metabolic activity, depending on the solution chemistry and the glass composition. The breakdown of organic carbon to volatile fatty acids increased glass dissolution. The interaction of microbially reduced Fe(II) with phosphorus-containing glass under anoxic conditions decreased dissolution rates, whereas the interaction of Fe(III) with phosphorus-containing glass under oxic conditions increased glass dissolution. Phosphorus addition to borosilicate glasses did not significantly affect the microbial species present, however, the diversity of the microbial community was enhanced on the surface of the iron phosphate glass. Results demonstrate the potential for microbes to influence the geochemistry of radioactive waste disposal environments with implication for wasteform durability.

Prospective Placebo-Controlled Assessment of Spore-Based Probiotic Supplementation on Sebum Production, Skin Barrier Function, and Acne

Probiotic supplementation has been shown to modulate the gut-skin axis. The goal of this study was to investigate whether oral spore-based probiotic ingestion modulates the gut microbiome, plasma short-chain fatty acids (SCFAs), and skin biophysical properties. This was a single-blinded, 8-week study (NCT03605108) in which 25 participants, 7 with noncystic acne, were assigned to take placebo capsules for the first 4 weeks, followed by 4 weeks of probiotic supplementation. Blood and stool collection, facial photography, sebum production, transepidermal water loss (TEWL), skin hydration measurements, and acne assessments were performed at baseline, 4, and 8 weeks. Probiotic supplementation resulted in a decreasing trend for the facial sebum excretion rate and increased TEWL overall. Subanalysis of the participants with acne showed improvement in total, noninflammatory, and inflammatory lesion counts, along with improvements in markers of gut permeability. The gut microbiome of the nonacne population had an increase in the relative abundance of Akkermansia, while the subpopulation of those with acne had an increase in the relative abundance of Lachnospiraceae and Ruminococcus gnavus. Probiotic supplementation augmented the circulating acetate/propionate ratio. There is preliminary evidence for the use of spore-based probiotic supplementation to shift the gut microbiome and augment short-chain fatty acids in those with and without acne. Further spore-based supplementation studies in those with noncystic acne are warranted.

Establishing an Academic-Community Partnership to Explore the Potential of Barbers and Barbershops in the Southern United States to Address Racial Disparities in HIV Care Outcomes for Black Men Living With HIV

Black men comprise most new HIV infections in the Southern United States and have worse HIV outcomes than their non-Black counterparts. We developed an academic-community partnership in Nashville, Tennessee, to explore opportunities to improve HIV outcomes for Black men. We recruited barbers to an HIV training and focus group discussion about prevention and potential barber/barbershop-based strategies to address HIV-related needs for Black men. We assessed HIV knowledge and stigma with validated scales and conducted thematic analysis on discussion transcripts. HIV-related stigma was low (1.8 of 15 points [SD = 1.69]) among 13 participants of unknown HIV status (12 men and one woman). HIV knowledge increased among eight (67%) participants after receiving a brief HIV didactic. Participants described general health care barriers (e.g., the social norm that Black men do not go to the doctor until they are "damn near dead"), fears about unwanted HIV disclosure when seeking HIV testing or care, and community fears about negative stereotypes associated with HIV. Participants expressed enthusiasm about receiving more HIV-related training and utilizing communication skills and client/community relationships to serve as health educators and navigators. Barbers highlighted opportunities to disseminate HIV information in barbershops and combine HIV interventions with other health issues, such as COVID-19, and suggested that these interventions may help reduce HIV-related stigma. Our findings suggest that barbers and barbershops are an underutilized resource for disseminating HIV-related health information and engaging Black men in HIV and other important prevention and care activities such as COVID-19.

Dysregulated energy metabolism impairs chondrocyte function in osteoarthritis

OBJECTIVES

Metabolic pathways are a series of chemical reactions by which cells take in nutrient substrates for energy and building blocks needed to maintain critical cellular processes. Details of chondrocyte metabolism and how it rewires during the progression of osteoarthritis (OA) are unknown. This research aims to identify what changes in the energy metabolic state occur in OA cartilage.

METHODS

Patient matched OA and non-OA cartilage specimens were harvested from total knee replacement patients. Cartilage was first collected for metabolomics, proteomics, and transcriptomics analyses to study global alterations in OA metabolism. We then determined the metabolic routes by tracking [U-¹³C] isotope with liquid chromatography-mass spectrometry (LC-MS). We further evaluated cellular bioenergetic profiles by measuring oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) and investigated the effects of low-dose and short-term effects of 2-deoxyglucose (2DG) on chondrocytes.

RESULTS

OA chondrocytes showed increased basal ECAR and more lactate production compared to non-OA chondrocytes. [U-¹³C] glucose labelling revealed that less glucose-derived carbon entered the tricarboxylic acid (TCA) cycle. On the other hand, mitochondrial respiratory rates were markedly decreased in the OA chondrocytes compared to non-OA chondrocytes. These changes were accompanied by decreased cellular ATP production, mitochondrial membrane potential and disrupted mitochondrial morphology. We further demonstrated in vitro that short-term inhibition of glycolysis suppressed matrix degeneration gene expression in chondrocytes and bovine cartilage explants cultured under inflammatory conditions.

CONCLUSION

This study represents the first comprehensive comparative analysis of metabolism in OA chondrocytes and lays the groundwork for therapeutic targeting of metabolism in OA.

Directly Cooling Gut Prevents Mortality in the Rat Model of Reboa Management of Lethal Hemorrhage

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a lifesaving technique for the management of lethal torso hemorrhage. Its benefit, however, must be weighed against the lethal distal organ ischemia-reperfusion injury (IRI). This study uses a novel direct gut cooling technique to manage the distal organ IRI.

METHODS

A rat lethal hemorrhage model was established by bleeding of 50% of the estimated total blood volume via inferior vena cava. A novel TransRectal Intra-Colon (TRIC) temperature management device was positioned in the descending colon either to maintain intra-colon temperature at 37°C or 12°C. The upper body temperature was maintained at as close to 37°C as possible in both groups. A 2F Fogarty balloon catheter was inserted via the femoral artery into the descending thoracic aorta for the implementation of REBOA. After REBOA, the balloon was deflated, and the shed blood was returned. The temperature managements were continued for additional 180 to 270 min during the post-REBOA period.

RESULTS

All rats subjected to REBOA management of lethal hemorrhage at 37°C had severe histopathological gut and abdominal organ IRI, severe functional deficits, and died within 24 h with 100% mortality. By contrast, directly cooling the colon to 10°C to 12°C with the novel TRIC device abolished mortality, and dramatically improved ABG parameters, prevented the abdominal organ injury, and reduced the functional deficits during the 7-day post-REBOA period.

CONCLUSIONS

Direct trans-rectal colon cooling during REBOA management of lethal hemorrhage offers extraordinary functional improvement and amazing tissue protection, and abolishes mortality.

Long-term core outcomes in cauda equina syndrome

AIMS

Cauda equina syndrome (CES) can be associated with chronic severe lower back pain and long-term autonomic dysfunction. This study assesses the recently defined core outcome set for CES in a cohort of patients using validated questionnaires.

METHODS

Between January 2005 and December 2019, 82 patients underwent surgical decompression for acute CES secondary to massive lumbar disc prolapse at our hospital. After review of their records, patients were included if they presented with the clinical and radiological features of CES, then classified as CES incomplete (CESI) or with painless urinary retention (CESR) in accordance with guidelines published by the British Association of Spinal Surgeons. Patients provided written consent and completed a series of questionnaires.

RESULTS

In total, 61 of 82 patients returned a completed survey. Their mean age at presentation was 43 years (20 to 77; SD 12.7), and the mean duration of follow-up 58.2 months (11 to 182; SD 45.3). Autonomic dysfunction was frequent: 33% of patients reported bladder dysfunction, and 10% required a urinary catheter. There was a 38% and 53% incidence of bowel and sexual dysfunction, respectively: 47% of patients reported genital numbness. A total of 67% reported significant back pain: 44% required further investigation and 10% further intervention for the management of lower back pain. Quality of life was lower than expected when corrected for age and sex. Half the patients reported moderate or worse depression, and 40% of patients of working age could no longer work due to problems attributable to CES. Urinary and faecal incontinence, catheter use, sexual dysfunction, and genital numbness were significantly more common in patients with CESR.

CONCLUSION

This study reports the long-term outcome of patients with CES and is the first to use validated patient-reported outcome measures to assess the CES Core Outcome Set. Persistent severe back pain and on-going autonomic dysfunction were frequently reported at a mean follow-up of five years. Cite this article: Bone Joint J 2021;103-B(9):1464-1471.

Resource Over-Utilization in Hospitalized Patients With Uncomplicated Skin and Soft Tissue Infections

BACKGROUND

Inpatient management of SSTIs utilizes considerable healthcare resources. The CREST+SEWS score categorizes patients with SSTIs into 4 severity classes. Hospitalizations can be avoided in Class I as they are treated as outpatients with oral antibiotics, whereas Class IV require hospitalization for intravenous antibiotics.

OBJECTIVE

The purpose of this study was to perform a budget impact analysis on CREST+SEWS Class 1 patients, to compare the medical costs of current treatment, in the inpatient setting with intravenous antibiotics, with a proposed alternative of using oral antibiotics in the outpatient setting. Further, resource utilization in Class I was evaluated.

METHODS

This was a retrospective study of adult patients hospitalized in 2015 for SSTIs who received >24 hours of antimicrobials. The CREST+SEWS scoring system was used to stratify patients into Class I to IV. Pharmacy and medical costs and resources associated with inpatient management of Class I SSTIs were derived from the itemized discharge records.

RESULTS

Of the 252 patients who met the inclusion criteria, 61 (24%) were classified as Class I. The total cost of treating Class I SSTI patients in the inpatient setting was $281,816 (cost per patient: $4,619) in 2015 USD. In the hypothetical situation of treatment with oral antibiotics in the outpatient setting, the cost savings were estimated to be $4,398 per patient. Fifty-three percent of patients had blood cultures, and on average, each patient received 2 radiographic tests.

CONCLUSIONS

Identifying outpatient candidates, and avoiding tests with low diagnostic can reduce the economic burden of SSTIs.

Natural organic matter does not diminish the mammalian bioavailability of 2,3,7,8-tetrachlorodibenzo-p-dioxin

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a toxic and persistent organic pollutant found in soils and sediments. It has been linked to several adverse health outcomes in humans and wildlife, including suppression of the immune system. TCDD is strongly sorbed to soils/sediments due to its extremely low water solubility. Presently, the bioavailability of soil/sediment-sorbed TCDD to mammals is not completely understood. Our previous studies demonstrated that TCDD adsorbed to representative inorganic geosorbents (i.e. porous silica and smectite clay) exhibited the same bioavailability to mice as TCDD dissolved in corn oil, whereas sequestration by activated carbons eliminated TCDD bioavailability. In this study, we evaluated the effects of amorphous natural organic matter (NOM), primarily in the form of aquatic humic and fulvic acids, on the mouse bioavailability of TCDD. An aqueous suspension of TCDD mixed with NOM was administered to mice via oral gavage. The relative bioavailability of TCDD was assessed by two sensitive aryl hydrocarbon receptor-mediated responses in mice: 1) hepatic induction of cyp1A1 mRNA; and 2) suppression of immunoglobulin M (IgM) antibody-forming cell (AFC) response which is an indicator of immunotoxicity. Hepatic induction of cyp1A1 mRNA and suppression of IgM AFC induced by TCDD were similar in the NOM-sorbed form and dissolved in corn oil, revealing no loss of bioavailability when associated with NOM. Hence, NOM-associated TCDD is as capable of suppressing humoral immunity in mice as TCDD dissolved in corn oil, indicating that NOM-sorbed TCDD is likely to fully retain its bioavailability to mammals and, by inference, humans.

Characterisation of ovine bone marrow-derived stromal cells (oBMSC) and evaluation of chondrogenically induced micro-pellets for cartilage tissue repair in vivo

Abstract

Bone marrow stromal cells (BMSC) show promise in cartilage repair, and sheep are the most common large animal pre-clinical model.

Objective

The objective of this study was to characterise ovine BMSC (oBMSC) in vitro, and to evaluate the capacity of chondrogenic micro-pellets manufactured from oBMSC or ovine articular chondrocytes (oACh) to repair osteochondral defects in sheep.

Design

oBMSC were characterised for surface marker expression using flow cytometry and evaluated for tri-lineage differentiation capacity. oBMSC micro-pellets were manufactured in a microwell platform, and chondrogenesis was compared at 2%, 5%, and 20% O₂. The capacity of cartilage micro-pellets manufactured from oBMSC or oACh to repair osteochondral defects in adult sheep was evaluated in an 8-week pilot study.

Results

Expanded oBMSC were positive for CD44 and CD146 and negative for CD45. The common adipogenic induction ingredient, 3-Isobutyl-1-methylxanthine (IBMX), was toxic to oBMSC, but adipogenesis could be restored by excluding IBMX from the medium. BMSC chondrogenesis was optimal in a 2% O₂ atmosphere. Micro-pellets formed from oBMSC or oACh appeared morphologically similar, but hypertrophic genes were elevated in oBMSC micro-pellets. While oACh micro-pellets formed cartilage-like repair tissue in sheep, oBMSC micro-pellets did not.

Conclusion

The sensitivity of oBMSC, compared to human BMSC, to IBMX in standard adipogenic assays highlights species-associated differences. Micro-pellets manufactured from oACh were more effective than micro-pellets manufactured from oBMSC in the repair of osteochondral defects in sheep. While oBMSC can be driven to form cartilage-like tissue in vitro, the effective use of these cells in cartilage repair will depend on the successful mitigation of hypertrophy and tissue integration.

Supplementary information

The online version contains supplementary material available at 10.1186/s13287-020-02045-3.

Attitudes towards risk-reducing early salpingectomy with delayed oophorectomy for ovarian cancer prevention: a cohort study

OBJECTIVE

To determine risk-reducing early salpingectomy and delayed oophorectomy (RRESDO) acceptability and effect of surgical prevention on menopausal sequelae/satisfaction/regret in women at increased ovarian cancer (OC) risk.

DESIGN

Multicentre, cohort, questionnaire study (IRSCTN:12310993).

SETTING

United Kingdom (UK).

POPULATION

UK women without OC ≥18 years, at increased OC risk, with/without previous RRSO, ascertained through specialist familial cancer/genetic clinics and BRCA support groups.

METHODS

Participants completed a 39-item questionnaire. Baseline characteristics were described using descriptive statistics. Logistic/linear regression models analysed the impact of variables on RRESDO acceptability and health outcomes.

MAIN OUTCOMES

RRESDO acceptability, menopausal sequelae, satisfaction/regret.

RESULTS

In all, 346 of 683 participants underwent risk-reducing salpingo-oophorectomy (RRSO). Of premenopausal women who had not undergone RRSO, 69.1% (181/262) found it acceptable to participate in a research study offering RRESDO. Premenopausal women concerned about sexual dysfunction were more likely to find RRESDO acceptable (odds ratio [OR] = 2.9, 95% CI 1.2-7.7, P = 0.025). Women experiencing sexual dysfunction after premenopausal RRSO were more likely to find RRESDO acceptable in retrospect (OR = 5.3, 95% CI 1.2-27.5, P < 0.031). In all, 88.8% (143/161) premenopausal and 95.2% (80/84) postmenopausal women who underwent RRSO, respectively, were satisfied with their decision, whereas 9.4% (15/160) premenopausal and 1.2% (1/81) postmenopausal women who underwent RRSO regretted their decision. HRT uptake in premenopausal individuals without breast cancer (BC) was 74.1% (80/108). HRT use did not significantly affect satisfaction/regret levels but did reduce symptoms of vaginal dryness (OR = 0.4, 95% CI 0.2-0.9, P = 0.025).

CONCLUSION

Data show high RRESDO acceptability, particularly in women concerned about sexual dysfunction. Although RRSO satisfaction remains high, regret rates are much higher for premenopausal women than for postmenopausal women. HRT use following premenopausal RRSO does not increase satisfaction but does reduce vaginal dryness.

TWEETABLE ABSTRACT

RRESDO has high acceptability among premenopausal women at increased ovarian cancer risk, particularly those concerned about sexual dysfunction.

Quinolone-induced Biceps Tendon Rupture

Presentation A 76-year-old man presented with acute left upper limb pain and subsequent large ecchymosis. Diagnosis An ultrasound study was performed which showed partial left biceps tendon rupture. Treatment He was managed conservatively with Orthopaedic input. The patient was given analgesia and reassured. Discussion Tendon rupture is an unusual but serious complication of quinolone exposure. This case highlights that this should be included in the differential for acute limb pain in patients who have been prescribed these drugs.

Randomized double-blind vehicle controlled study of the effects of topical acetyl zingerone on photoaging

OBJECTIVE

Acetyl zingerone (AZ), a derivative of the phytochemical zingerone from Zingiber officinale (ginger), is a novel compound that is purported to have antiaging properties. The objective of this clinical study was to assess the role of acetyl zingerone in its ability to improve the appearance of facial skin wrinkles, redness, pigmentation, and photoaging was assessed.

METHODS

Thirty-one healthy participants (age 44 ± 7 years) were randomized in blinded fashion to apply either 1% AZ or placebo, consisting of the vehicle base cream, to the full face twice daily for 8 weeks with a total of 3 visits. Signs of photoaging, including wrinkles, dyspigmentation, and redness were assessed with facial image analysis photography and software.

RESULTS

There was a significant decrease in average wrinkle severity (P = .019; Mean=-25.7% change), total wrinkle volume (P = .003; Mean=-30.1% change), pigment intensity (P = .021; Mean=-25.6% change), and redness intensity (P = .035; Mean=-20.7% change) in the AZ group by 8 weeks compared with the placebo. No significant itching, burning, or stinging was noted by study participants. There was also no significant difference between both groups in the clinical assessment of scaling, erythema, hypopigmentation, or hyperpigmentation.

CONCLUSIONS AND RELEVANCE

Topical AZ improves photodamage and decreases the appearance of wrinkles, dyspigmentation, and redness intensity when compared to placebo (vehicle) formulation. Acetyl zingerone is well tolerated with daily use.

Object surveillance with radio-frequency atomic magnetometers

The capabilities of a radio-frequency atomic magnetometer for object detection based on magnetic induction tomography are explored. The determination of object orientation is demonstrated by utilizing the measurement geometry. The self-compensation configuration of the atomic magnetometer is implemented to address the issue of saturation of the sensor response by the radio-frequency primary field that generates the object signature. Three methods of "covert" detection are investigated as a testbed for exploring the functionalities of this sensor, where (1) the operational frequency of the sensor is continuously changed, (2) the primary field has non-monochromatic frequency distribution, and (3) the sensor operates in the so-called spin maser mode. The results of the measurements are also discussed in terms of possible magnetic field communication.

Deep Learning-Based Femoral Cartilage Automatic Segmentation in Ultrasound Imaging for Guidance in Robotic Knee Arthroscopy

Knee arthroscopy is a minimally invasive surgery used in the treatment of intra-articular knee pathology which may cause unintended damage to femoral cartilage. An ultrasound (US)-guided autonomous robotic platform for knee arthroscopy can be envisioned to minimise these risks and possibly to improve surgical outcomes. The first necessary tool for reliable guidance during robotic surgeries was an automatic segmentation algorithm to outline the regions at risk. In this work, we studied the feasibility of using a state-of-the-art deep neural network (UNet) to automatically segment femoral cartilage imaged with dynamic volumetric US (at the refresh rate of 1 Hz), under simulated surgical conditions. Six volunteers were scanned which resulted in the extraction of 18278 2-D US images from 35 dynamic 3-D US scans, and these were manually labelled. The UNet was evaluated using a five-fold cross-validation with an average of 15531 training and 3124 testing labelled images per fold. An intra-observer study was performed to assess intra-observer variability due to inherent US physical properties. To account for this variability, a novel metric concept named Dice coefficient with boundary uncertainty (DSC_UB) was proposed and used to test the algorithm. The algorithm performed comparably to an experienced orthopaedic surgeon, with DSC_UB of 0.87. The proposed UNet has the potential to localise femoral cartilage in robotic knee arthroscopy with clinical accuracy.

Evaluation of VIDAS® Salmonella (SLM) Immunoassay Method with Rappaport-Vassiliadis (RV) Medium for Detection of Salmonella in Foods: Collaborative Study

A collaborative study was conducted to compare the VIDAS Salmonella (SLM) with Rappaport-Vassiliadis (RV) method for detection of Salmonella in foods to the current standard method presented in the U.S. Food and Drug Administration's Bacteriological Analytical Manual (BAM) and the culture method presented in AOAC's Official Methods of Analysis. The VIDAS SLM with RV method uses tetrathionate broth in combination with RV medium in place of selenite cystine broth for selective enrichment, thereby eliminating the hazardous waste issue for laboratories. Twenty five laboratories participated in the evaluation, each testing one or more of 8 test products: nonfat dry milk, dried egg, soy flour, lactic casein, milk chocolate, raw ground pork, raw ground turkey, and raw peeled shrimp. Results of the study showed no significant differences in the numbers of confirmed positive samples with the VIDAS SLM with RV procedure and the BAM/AOAC culture procedure. The VIDAS SLM with RV method was effective for rapid detection of Salmonella in foods. It is recommended that AOAC INTERNATIONAL modify the VIDAS Salmonella SLM procedure to include the RV method.

TCDD-mediated suppression of naïve human B cell IgM secretion involves aryl hydrocarbon receptor-mediated reduction in STAT3 serine 727 phosphorylation and is restored by interferon-γ

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a persistent environmental contaminant formed as a byproduct in organic synthesis and burning of organic materials. TCDD has potent immunotoxic effects in B lymphocytes resulting in decreased cellular activation and suppressed IgM secretion following activation with CD40 ligand. Previous work from our lab demonstrated that TCDD treatment of naïve human B cells resulted in significant increases in the levels of the tyrosine phosphatase SHP-1, which corresponded with suppression of IgM secretion. STAT3 is a critical B cell transcription factor for B cell activation and secretion of immunoglobulins (Ig). STAT3 dimerizes and translocates to the nucleus following phosphorylation as a result of cytokine receptor signaling. We hypothesized that TCDD-mediated increases in SHP-1 could result in decreased STAT3 tyrosine phosphorylation. Interestingly, only modest changes in the levels of STAT3 tyrosine phosphorylation were observed. By contrast, TCDD significantly reduced levels of STAT3 serine phosphorylation as early as 12h post B cell activation. These results corresponded with decreased inhibitory phosphorylation of the serine specific phosphatase PP2a, which is regulated by SHP-1. Further, studies revealed that interferon gamma (IFNγ), which signals through the type II interferon receptor, can non-canonically induce STAT3 activation via Src kinase activity. Indeed, treatment of human B cells with IFNγ resulted in increased STAT3 serine phosphorylation and reversed TCDD-mediated suppression of the IgM response. Together, these data putatively identify a key event in the mechanism by which TCDD induces suppression of Ig secretion and demonstrate the potential of IFNγ as a means to reverse this effect in primary human B lymphocytes.

Suppression of the IgM Response by Aryl Hydrocarbon Receptor Activation in Human Primary B Cells Involves Impairment of Immunoglobulin Secretory Processes

Aryl hydrocarbon receptor (AHR) activation by 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) is well established at suppressing humoral immunity. Previous studies in mouse B cells revealed that decreased IgM production was due to a significant suppression in the mRNA levels of the immunoglobulin M components (IgH, IgJ, and Igκ chains) and subsequent decrease in IgM synthesis. In contrast, the current study shows that activation of AHR in human B cells also results in a significant suppression of the number of IgM-secreting cells, but this is not due to a decrease in the transcription or translation of IgH, IgJ, and Igκ chains. Instead, the reduced humoral response is due to the impairment of IgM secretion. This is further evidenced by an accumulation of intracellular IgM in human B cells, which indicates that activation of AHR alters distinct regulatory pathways in human and mouse B cells leading to the suppressed primary IgM response. Collectively, these results demonstrate that although AHR activation mediates suppression of humoral immune responses across many different animal species, the mechanism of action is not necessarily conserved across species.

Safety in steep slope logging operations

Partial results of a NIOSH-funded study for "Protecting the Logging Workforce: Development of Innovative Logging Techniques for a Safer Work Environment" by a team of researchers at Oregon State University are presented that review safety in steep slope logging. Comparisons are made for hazards and exposures of "conventional" and new technologies for steep slopes. Hazards of new technologies are identified. Safety assessments are addressed for forestry sectors internationally, for the firm and for workers. Important questions of technical feasibility, economic viability and environmental performance are raised. Ongoing research on operators using tethered and untethered systems are described. Results will help inform training and selecting operators. New Best Operating Practices and safety code regulations will result from the research. New technologies will reduce worker hazards and exposures for steep slope logging.

A tractable, simplified ex vivo human skin model of wound infection

The prevalence of infection in chronic wounds is well documented in the literature but not optimally studied due to the drawbacks of current methodologies. Here, we describe a tractable and simplified ex vivo human skin model of infection that addresses the critical drawbacks of high costs and limited translatability. Wounds were generated from excised abdominal skin from cosmetic procedures and cultured, inoculated with Staphylococcus aureus strain UAMS-1, or under aseptic conditions. After three days, the infected wounds exhibited biofilm formation and significantly impaired reepithelialization compared to the control. Additionally, promigratory and proreparative genes were significantly downregulated, while proinflammatory genes were significantly upregulated, demonstrating molecular characterizations of impaired healing as in chronic wounds. This model allows for a simplified and versatile tool for the study of wound infection and subsequent development of novel therapies.

Activated carbons of varying pore structure eliminate the bioavailability of 2,3,7,8-tetrachlorodibenzo-p-dioxin to a mammalian (mouse) model

The use of activated carbon (AC) as an in situ sorbent amendment to sequester polychlorinated-dibenzo-p-dioxins and furans (PCDD/Fs) present in contaminated soils and sediments has recently gained attention as a novel remedial approach. This remedy could be implemented at much lower cost while minimizing habitat destruction as compared to traditional remediation technologies that rely on dredging/excavation and landfilling. Several prior studies have demonstrated the ability of AC amendments to reduce pore water concentrations and hence bioaccumulation of PCDD/Fs in invertebrate species. However, our recent study was the first to show that AC had the ability to sequester 2,3,7,8‑tetrachlorodibenzo‑p‑dioxin (TCDD) in a form that eliminated bioavailability to a mammalian (mouse) model. Here we show that three commercially available ACs, representing a wide range of pore size distributions, were equally effective in eliminating the bioavailability of TCDD based upon two sensitive bioassays, hepatic induction of cyp1A1 mRNA and immunoglobulin M antibody-forming cell response. These results provide direct evidence that a wide range of structurally diverse commercially available ACs may be suitable for use as in situ sorbent amendments to provide a cost-effective remedy for PCDD/F contaminated soils and sediments. Potentially, adaption of this technology would minimize habitat destruction and be protective of ecosystem and human health.

Preparing and sharing food: a quantitative analysis of a primary school-based food intervention

Background

Primary schools are increasingly used as arenas for public health initiatives. The aim of this study was to assess a primary school-based food intervention.

Methods

The intervention comprised timetabled kitchen classroom sessions (90 min, fortnightly). Pupils prepared and cooked food, which they then ate together. Children's relationship with food, including food enjoyment, experience and food neophobia, were addressed at the intervention school (baseline n = 154; follow-up n = 164) and at a matched control school (baseline n = 171; follow-up n = 174).

Results

Pupils at the intervention school scored significantly higher (M = 3.90, SD = 1.81) for scores on Kitchen Equipment, compared to the control school (M = 3.06, SD = 2.12); and again scored significantly higher (M = 9.34, SD = 3.79) for the overall Cooking Experience Score compared to the control school (M = 7.98, SD = 4.57). Shifts accompanying the intervention in three outcome measures for pupils (taste description, liking for cooking and helping with cooking at home) were also revealed. No main intervention effect for food neophobia and fussiness was found; a close to significant time by intervention interaction (P = 0.053) was evident.

Conclusions

The study indicates limited but encouraging changes, and contributes to the growing literature regarding school-based food initiatives.

Lymphocyte-specific protein tyrosine kinase (LCK) is involved in the aryl hydrocarbon receptor (AHR)-mediated impairment of Immunoglobulin secretion in human primary B cells

AHR activation by the high affinity ligand, TCDD, is widely established to suppress the immunoglobulin M (IgM) response in virtually every animal species tested, and extensively investigated in various mouse models. In mice, activation of AHR is known to impair B cell to plasma cell differentiation and IgM synthesis. In contrast to mouse B cells, activation of AHR in human primary B cells impairs immunoglobulin secretion in the absence of suppressing IgM synthesis. In recent studies, we have identified the putative involvement of LCK in impaired immunoglobulin secretion by human B cells. LCK is a well-characterized tyrosine kinase that phosphorylates known critical signaling proteins involved in vesicular secretion by T cells. Specifically, phosphorylation of tyrosine residue 505 inhibits the activity of LCK. By contrast, little is known concerning the role of LCK in human primary B cells. For the first time, our studies show that activation of the AHR by TCDD upregulates LCK protein expression, which then leads to an impairment of IgM secretion. Treatment with a LCK specific inhibitor restores IgM secretion by human primary B cells. Additionally, the presence of AHR antagonist reverses the AHR-mediated increase of LCK and the impairment of IgM secretion. We also observe a significant increase in phosphorylation of Tyr-505 LCK with TCDD treatment, indicating that AHR activation increases the level of inhibitory LCK. Taken together, our studies revealed a novel and species-dependent mechanism involving the AHR-mediated impairment of IgM secretion and an increase in total as well as inhibitory LCK in human but not mouse primary B cells.

Laser Fenestration for Treatment of a Complicated Chronic Type B Aortic Dissection

We report a case of a complex chronic type B aortic dissection treated by thoracic endovascular aortic repair and laser fenestration of the false septum to preserve flow to branch vessels originating from both the true and false lumen. Dissections complicated by thoracoabdominal aneurysmal degeneration with critical organs being perfused by branches arising from both true and false lumens are rare and leave limited options for repair. Despite advancements in endovascular techniques, fenestration remains one of the only means of preserving flow to both the true and false lumens and thus was necessary in the management of our patient. This novel procedure allows complex aortic dissections to be addressed endovascularly, which increases the flexibility and management of this challenging problem that previously required an open repair with significant morbidity.

Application of gene specific mRNA level determinations in individual cells using flow cytometry-based PrimeFlow™ in immunotoxicology

Determining changes in gene expression by measuring mRNA levels is an important capability in biological research. Real-Time Quantitative PCR (RT-qPCR) is the most ubiquitous technique for measuring changes in mRNA transcript levels, but heterogeneity of cell populations and low cell number are serious technical limitations. Recent advances in flow cytometric analytical techniques have enabled the quantification of mRNA levels in individual cells. Here, we present examples demonstrating the strength and challenges of concurrently measuring mRNA using PrimeFlow™ with other endpoints in immunotoxicological studies. Specifically, we demonstrate how measuring gene specific mRNA levels on a per cell basis was used to study: 1) markers of activation and differentiation; 2) cell signaling by measuring intracellular proteins in mature and developing cell types; and 3) a cell type that constitutes a minor population in peripheral blood. We also discuss cell type-specific modifications to the parent technique, which facilitated optimal performance in these cells. While the examples provided are focused on immunotoxicological questions and endpoints, this new strategy can be applied to a wide variety of toxicological research problems.

Sequestration of 2,3,7,8-tetrachlorodibenzo-p-dioxin by activated carbon eliminates bioavailability and the suppression of immune function in mice

The effectiveness of activated carbon in reducing the bioavailability of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was examined from the context of using in situ sorbent amendments to remediate soils/sediments contaminated with polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs). This technology has gained rapid acceptance based on observations that activated carbon amendments predictably lower PCDD/F concentrations in water and bioaccumulation by simple aquatic organisms and earthworms; it has been assumed that bioavailability to mammals is similarly reduced, although this has been disproven for other sorbent materials. In the present study TCDD was absorbed to a microporous activated carbon (TCDD-AC) using the incipient wetness method. An aqueous suspension of TCDD-AC and an equivalent dosage of TCDD in corn oil were administered by oral gavage to B6C3F1 mice. The relative bioavailability of TCDD-AC was determined by quantifying and comparing the hepatic induction of cyp1A1 (messenger ribonucleic acid) and suppression of the immunoglobulin M antibody-forming cell immune response by the 2 forms of TCDD. A concentration-dependent response was observed for both assays when TCDD in corn oil was administered to mice. However, when equivalent masses of TCDD were administered as TCDD-AC, no induction of cyp1A1 or suppression of the immunoglobulin M antibody-forming cell response was observed. The absence of these 2 sensitive aryl hydrocarbon receptor-mediated responses in mice provides the first direct evidence that activated carbon can sequester TCDD in a form that eliminates its bioavailability to mammals. These results support the premise that activated carbon can be used to reduce the bioeffective dose of TCDD delivered to mammals and that activated carbon amendments may provide a low-cost alternative to traditional remediation technologies. Environ Toxicol Chem 2017;36:2671-2678. © 2017 SETAC.

Magnetically controlled growing rods in the treatment of early-onset scoliosis

The MAGnetic Expansion Control (MAGEC) system is used increasingly in the management of early-onset scoliosis. Good results have been published, but there have been recent reports identifying implant failures that may be associated with significant metallosis surrounding the implants. This article aims to present the current knowledge regarding the performance of this implant, and the potential implications and strategies that may be employed to identify and limit any problems.

We urge surgeons to apply caution to patient and construct selection; engage in prospective patient registration using a spine registry; ensure close clinical monitoring until growth has ceased; and send all explanted MAGEC rods for independent analysis.

The MAGEC system may be a good instrumentation system for the treatment of early-onset scoliosis. However, it is innovative and like all new technology, especially when deployed in a paediatric population, robust systems to assess long-term outcome are required to ensure that patient safety is maintained.

Cite this article: Bone Joint J 2017;99-B:708–13.

At-sea distribution and habitat use in king penguins at sub-Antarctic Marion Island

King penguins make up the bulk of avian biomass on a number of sub‐Antarctic islands where they have a large functional effect on terrestrial and marine ecosystems. The same applies at Marion Island where a substantial proportion of the world population breeds. In spite of their obvious ecological importance, the at‐sea distribution and behavior of this population has until recently remained entirely unknown. In addressing this information deficiency, we deployed satellite‐linked tracking instruments on 15 adult king penguins over 2 years, April 2008 and 2013, to study their post‐guard foraging distribution and habitat preferences. Uniquely among adult king penguins, individuals by and large headed out against the prevailing Antarctic Circumpolar Current, foraging to the west and southwest of the island. On average, individuals ventured a maximum distance of 1,600 km from the colony, with three individuals foraging close to, or beyond, 3,500 km west of the colony. Birds were mostly foraging south of the Antarctic Polar Front and north of the southern boundary of the Antarctic Circumpolar Current. Habitat preferences were assessed using boosted regression tree models which indicated sea surface temperate, depth, and chorophyll a concentration to be the most important predictors of habitat selection. Interestingly, king penguins rapidly transited the eddy‐rich area to the west of Marion Island, associated with the Southwest Indian Ocean Ridge, which has been shown to be important for foraging in other marine top predators. In accordance with this, the king penguins generally avoided areas with high eddy kinetic energy. The results from this first study into the behavioral ecology and at‐sea distribution of king penguins at Marion Island contribute to our broader understanding of this species.

Comparative analysis of TCDD-induced AhR-mediated gene expression in human, mouse and rat primary B cells

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a persistent environmental pollutant that activates the aryl hydrocarbon receptor (AhR) resulting in altered gene expression. In vivo, in vitro, and ex vivo studies have demonstrated that B cells are directly impaired by TCDD, and are a sensitive target as evidenced by suppression of antibody responses. The window of sensitivity to TCDD-induced suppression of IgM secretion among mouse, rat and human B cells is similar. Specifically, TCDD must be present within the initial 12h post B cell stimulation, indicating that TCDD disrupts early signaling network(s) necessary for B lymphocyte activation and differentiation. Therefore, we hypothesized that TCDD treatment across three different species (mouse, rat and human) triggers a conserved, B cell-specific mechanism that is involved in TCDD-induced immunosuppression. RNA sequencing (RNA-Seq) was used to identify B cell-specific orthologous genes that are differentially expressed in response to TCDD in primary mouse, rat and human B cells. Time course studies identified TCDD-elicited differential expression of 515 human, 2371 mouse and 712 rat orthologous genes over the 24-h period. 28 orthologs were differentially expressed in response to TCDD in all three species. Overrepresented pathways enriched in all three species included cytokine-cytokine receptor interaction, ECM-receptor interaction, focal adhesion, regulation of actin cytoskeleton and pathways in cancer. Differentially expressed genes functionally associated with cell-cell signaling in humans, immune response in mice, and oxidation reduction in rats. Overall, these results suggest that despite the conservation of the AhR and its signaling mechanism, TCDD elicits species-specific gene expression changes.