Retaining dermatology patients in primary care through dialogue with secondary care providers: A service evaluation

BACKGROUND

There are long patient waiting lists for specialist care. A dermatology dialogue service between primary and secondary care (DDPS) was developed in eastern England. Primary care referrers uploaded patient images of skin conditions for review by and dialogue with consultant dermatologists in an attempt to retain patients in primary care rather than refer them to secondary care.

METHODS

Evaluation of service performance against specific targets, including reduction in secondary care waiting list growth over the period April 2021-March 2022 inclusive. Service activity was summarized in terms of speed of resolution, case numbers, and dispositions. Clinician and patient satisfaction were assessed using structured questionnaires. Actual numbers of new referrals were compared to projections based on historical data. Waiting list growth was compared to other specialties and other commissioning areas. Waiting times to initial treatment were monitored.

RESULTS

Over 3300 patients were enrolled and > 90% of dialogues were resolved within 36 hours. Clinician and patient satisfaction were high. Frequently asked questions and conditions were highlighted by dermatologists to design and deliver an educational event for primary care clinicians that was well received. Waiting list growth for dermatology patients in the commissioning area was smaller than for other major specialties, and generally smaller than growth for dermatology waiting lists commissioned by other NHS commissioners. There was no negative impact on the urgent priority (cancer pathway) waiting list.

CONCLUSION

The DDPS was satisfactory for clinicians and patients and coincided with lower growth in dermatology waiting lists than might otherwise have been expected.

Third international challenge to model the medium- to long-range transport of radioxenon to four Comprehensive Nuclear-Test-Ban Treaty monitoring stations

In 2015 and 2016, atmospheric transport modeling challenges were conducted in the context of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification, however, with a more limited scope with respect to emission inventories, simulation period and number of relevant samples (i.e., those above the Minimum Detectable Concentration (MDC)) involved. Therefore, a more comprehensive atmospheric transport modeling challenge was organized in 2019. Stack release data of Xe-133 were provided by the Institut National des Radioéléments/IRE (Belgium) and the Canadian Nuclear Laboratories/CNL (Canada) and accounted for in the simulations over a three (mandatory) or six (optional) months period. Best estimate emissions of additional facilities (radiopharmaceutical production and nuclear research facilities, commercial reactors or relevant research reactors) of the Northern Hemisphere were included as well. Model results were compared with observed atmospheric activity concentrations at four International Monitoring System (IMS) stations located in Europe and North America with overall considerable influence of IRE and/or CNL emissions for evaluation of the participants' runs. Participants were prompted to work with controlled and harmonized model set-ups to make runs more comparable, but also to increase diversity. It was found that using the stack emissions of IRE and CNL with daily resolution does not lead to better results than disaggregating annual emissions of these two facilities taken from the literature if an overall score for all stations covering all valid observed samples is considered. A moderate benefit of roughly 10% is visible in statistical scores for samples influenced by IRE and/or CNL to at least 50% and there can be considerable benefit for individual samples. Effects of transport errors, not properly characterized remaining emitters and long IMS sampling times (12-24 h) undoubtedly are in contrast to and reduce the benefit of high-quality IRE and CNL stack data. Complementary best estimates for remaining emitters push the scores up by 18% compared to just considering IRE and CNL emissions alone. Despite the efforts undertaken the full multi-model ensemble built is highly redundant. An ensemble based on a few arbitrary runs is sufficient to model the Xe-133 background at the stations investigated. The effective ensemble size is below five. An optimized ensemble at each station has on average slightly higher skill compared to the full ensemble. However, the improvement (maximum of 20% and minimum of 3% in RMSE) in skill is likely being too small for being exploited for an independent period.

Metastatic Medullary Thyroid Cancer: The Role of 68Gallium-DOTA-Somatostatin Analogue PET/CT and Peptide Receptor Radionuclide Therapy

CONTEXT

Metastatic medullary thyroid cancer (MTC) is a rare malignancy with minimal treatment options. Many, but not all, MTCs express somatostatin receptors.

OBJECTIVE

Our aim was to explore the role of 68Ga-DOTA-somatostatin analogue (SSA) positron emission tomography (PET)/computed tomography (CT) in patients with metastatic MTC and to determine their eligibility for peptide receptor radionuclide therapy (PRRT).

METHODS

We retrospectively identified patients with metastatic MTC who had 68Ga-DOTA-SSA PET/CT at 5 centers. We collected characteristics on contrast-enhanced CT, 68Ga-DOTA-SSA and 18F-FDG PET/CT. The efficacy of PRRT was explored in a subgroup of patients. Kaplan-Meier analysis was used to estimate time to treatment failure (TTF) and overall survival (OS).

RESULTS

Seventy-one patients were included (10 local recurrence, 61 distant disease). Of the patients with distant disease, 16 (26%) had ≥50% of disease sites with tracer avidity greater than background liver, including 10 (10/61, 16%) with >90%. In 19 patients with contemporaneous contrast-enhanced CT, no disease regions were independently identified on 68Ga-DOTA-SSA PET/CT. Thirty-five patients had an 18F-FDG PET/CT, with 18F-FDG positive/68Ga-DOTA-SSA negative metastases identified in 15 (43%). Twenty-one patients had PRRT with a median TTF of 14 months (95% CI 8-25) and a median OS of 63 months (95% CI 21-not reached). Of the entire cohort, the median OS was 323 months (95% CI 152-not reached). Predictors of poorer OS included a short calcitonin doubling-time (≤24 months), strong 18F-FDG avidity, and age ≥60 years.

CONCLUSIONS

The prevalence of high tumor avidity on 68Ga-DOTA-SSA PET/CT is low in the setting of metastatic MTC; nevertheless, PRRT may still be a viable treatment option in select patients.

Understanding the Treatment Algorithm of Patients with Metastatic Pancreatic Neuroendocrine Neoplasms: A Single-Institution Retrospective Analysis Comparing Outcomes of Chemotherapy, Molecular Targeted Therapy, and Peptide Receptor Radionuclide Therapy in 255 Patients

BACKGROUND

The number of therapeutic options for patients with pancreatic neuroendocrine neoplasms (PNEN) has increased, but the optimal therapeutic algorithm has not been defined due to lack of randomised trials comparing different modalities.

METHODS

We performed a retrospective study in patients with metastatic PNEN treated with ≥1 line of systemic therapy. The relationship between baseline characteristics, treatment type, and time to treatment failure (TTF), time to progression (TTP), and overall survival (OS) was analysed using the Kaplan-Meier method. Univariate and multivariate analyses were performed using the Cox proportional hazards model.

RESULTS

Two hundred and fifty-five patients with metastatic PNEN had 491 evaluable lines of therapy. Independent predictors of TTF included treatment type, Ki-67, tumour grade, and chromogranin A. To reduce selection bias, a subgroup of 114 patients with grade 2 (G2) metastatic pancreatic neuroendocrine tumours (PNET) was analysed separately. These patients had received 234 lines of treatment (105 chemotherapy, 82 molecular targeted therapy, and 47 peptide receptor radionuclide therapy [PRRT]). In the G2 cohort, TTF and TTP were superior for PRRT compared with both chemotherapy and molecular targeted therapy. OS in the G2 cohort was also superior for those that had received PRRT compared with those that had not (median 84 vs. 56 months; HR 0.55, 95% CI: 0.31-0.98, p = 0.04).

CONCLUSIONS

This study suggests that PRRT is associated with superior clinical outcomes relative to other systemic therapies for G2 metastatic PNET. Prospective studies are required to confirm these observations.

Bioprosthetic valve fracture during valve-in-valve transcatheter aortic valve replacement

Transcatheter aortic valve replacement (TAVR) valve-in-valve (VIV) therapy has been approved for select patients with surgically inoperable bioprosthetic valves that need replacement. Bioprosthetic valve fracturing (BVF) used in conjunction with VIV TAVR can reduce transvalvular gradients and increase the aortic valve area. Twelve patients who underwent BVF VIV TAVR at a single center were retrospectively analyzed. Measurements of hemodynamics and aortic valve area were performed at baseline, after VIV TAVR, after BVF, and at 30-day follow-up. The mean Society of Thoracic Surgeons Predicted Risk of Mortality score was 7.12 ± 3.5%, with 75% of patients deemed high risk by the heart team. Mean gradients decreased from 44 mm Hg to 15 mm Hg following VIV TAVR, and to 7 mm Hg following BVF. The mean aortic valve area increased from 0.6 cm² to 1 cm² following VIV TAVR, and to 1.3 cm² following BVF. There were no postoperative permanent pacemaker implantations or vascular complications, and at 30 days, only one patient had died. While we report intraoperative mortality, BVF with VIV TAVR can be performed to reduce transvalvular gradients and increase effective aortic valve area in high-surgical-risk patients with failed bioprosthetic valves.

Cardenolide-rich fraction of Pergularia tomentosa as a novel Antiangiogenic agent mainly targeting endothelial cell migration

PURPOSE

Angiogenesis related abnormalities underlie several life-threatening disorders. Despite approved therapies, scientists have yet to develop highly efficient, low cost approaches with minimal side effects.

METHODS

We evaluated the antiangiogenic activity of 50% hydroalcoholic extracts of Pergularia tomentosa L. root and aerial parts along with their EtOAc and water fractions, in vivo and in vitro. Transgenic zebrafish line Tg(fli1:EGFP) was used for in vivo assay and human umbilical vein endothelial cell (HUVEC) migration test along with possibility of tube formation were performed as in vitro tests. Furthermore, microvasculature in chicken chorioallantoic membrane (CAM) was assessed under P. tomentosa treatment. The fractionation of the 50% hydroalcoholic extracts was led to the identification of the best active fraction in this study. The metabolite profiling of the active fraction was also carried out using LC-HRESIMS analysis.

RESULTS

Pergularia tomentosa markedly inhibited intersegmental vessel (ISV) formation at 48 h post-fertilization (hpf) embryos in zebrafish. The water fraction of root hydroalcoholic extract (PtR2), showed strong antiangiogenic effect with minimal adverse viability impacts. Over 80% of embryos showed more than 50% inhibition in their ISV development at 20 and 40 μg/mL. PtR2 at 20 μg/mL substantially reduced human umbilical vein endothelial cell (HUVEC) migration up to 40%, considerable destruction of the formed tubes in the tube formation and microvasculature in CAM assays. Immunocytochemistry showed a marked reduction in vascular endothelial cadherin (VE-cadherin) abundance at cell junctions concurrent with substantial reduction of phospho-Akt (p-Akt) and β-catenin protein expressions. Phytochemical profile of PtR2 showed a rich source of cardenolide structures, including ghalakinoside, calactin and calotropin derivatives.

CONCLUSION

Thus, the P. tomentosa cardenolide-rich fraction (PtR2) may hold a considerable promise for an antiangiogenic impact by impairment of endothelial cell (EC) migration and viability. Graphical abstract.

Transcriptome profiling data reveals ubiquitin-specific peptidase 9 knockdown effects

Ubiquitin specific peptidase 9 (USP9) is a deubiquitinase encoded by a sex-linked gene with a Y-chromosomal form (USP9Y) and an X-chromosomal form (USP9X) that escapes X-inactivation. Since USP9 is a key regulatory gene with sex-linked expression in the human brain, the gene may be of interest for researchers studying molecular gender differences and ubiquitin signaling in the brain.

To assess the downstream effects of knocking down USP9X and USP9Y on a transcriptome-wide scale, we have conducted microarray profiling experiments using the human DU145 prostate cancer cell culture model, after confirming the robust expression of both USP9X and USP9Y in this model. By designing shRNA constructs for the specific knockdown of USP9X and the joint knockdown of USP9X and USP9Y, we have compared gene expression changes in both knockdowns to control conditions to infer potential shared and X- or Y-form specific alterations. Here, we provide details of the corresponding microarray profiling data, which has been deposited in the Gene Expression Omnibus database (GEO series accession number GSE79376). A biological interpretation of the data in the context of a potential involvement of USP9 in Alzheimer's disease has previously been presented in Köglsberger et al. (2016). To facilitate the re-use and re-analysis of the data for other applications, e.g. the study of ubiquitin signaling and protein turnover control, and the regulation of molecular gender differences in the human brain and brain-related disorders, we provide a more in-depth discussion of the data properties, specifications and possible use cases.

Robotic Repair of a Congenital Isolated Cleft of Anterior Tricuspid Valve Leaflet

Congenital isolated tricuspid valve (TV) cleft in the anterior leaflet is a rare occurrence, while clefts of the mitral valve leaflets are more common and are usually associated with other congenital heart diseases. In this article, we report a case of TV regurgitation in a young adult female due to an isolated congenital cleft in the anterior TV leaflet, which was surgically repaired using a minimally invasive robotic approach.

Intraocular Pressure Increases After Intraarticular Knee Injection With Triamcinolone but Not Hyaluronic Acid

BACKGROUND

Intraarticular steroid injections are a common first-line therapy for severe osteoarthritis, which affects an estimated 27 million people in the United States. Although topical, oral, intranasal, and inhalational steroids are known to increase intraocular pressure in some patients, the effect of intraarticular steroid injections on intraocular pressure has not been investigated, to the best of our knowledge. If elevated intraocular pressure is sustained for long periods of time or is of sufficient magnitude acutely, permanent loss of the visual field can occur.

QUESTIONS/PURPOSES

How does intraocular pressure change 1 week after an intraarticular knee injection either with triamcinolone acetonide or hyaluronic acid?

METHODS

A nonrandomized, nonblinded prospective cohort study was conducted at an outpatient, ambulatory orthopaedic clinic. This study compared intraocular pressure elevation before and 1 week after intraarticular knee injection of triamcinolone acetonide versus hyaluronic acid for management of primary osteoarthritis of the knee. Patients self-selected to be injected in their knee with either triamcinolone acetonide or hyaluronic acid before being informed of the study. The primary endpoint was intraocular pressure elevation of ≥ 7 mm Hg 1 week after injection. This cutoff is determined as the minimum significant pressure change in the ophthalmology literature recognized as an intermediate responder to steroids. Intraocular pressure was measured using a handheld Tono-Pen® applanation device. This device is frequently used in intraocular pressure measurement in clinical and research settings; 10 sequential measurements are obtained and averaged with a confidence interval. Only measurements with a 95% confidence interval were used. Over a 6-month period, a total of 96 patients were approached to enroll in the study. Sixty-two patients out of 96 approached (65%) agreed. Thirty-one (50%) were injected with triamcinolone and 31 (50%) were injected with hyaluronic acid. Patients with osteoarthritis of the knee who were suitable candidates for either a steroid injection or hyaluronic acid injection were included in the study. Exclusion criteria included previous glaucoma surgery, previous corneal injury precluding use of a Tono-Pen, current acute or chronic steroid use, and diagnosis of glaucoma other than primary open-angle. Patients with elevated intraocular pressure at the 1-week timepoint were invited to return at 1 month for repeat measurement; however, only five of nine (55.6%) were able to do so. The mean age of the total population was 64.1 ± 11.65 years. There were 46 (74%) women and 16 men. Patient in the hyaluronic acid injection group were younger than the triamcinolone group, 59.5 ± 11.7 versus 68.7 ± 9.7 years of age (p < 0.003).

RESULTS

The mean intraocular pressure increased by 2.79 mm Hg 1 week after treatment with triamcinolone, but it did not change among those patients treated with hyaluronic acid (2.79 ± 9.9 mm Hg versus -0.14 ± 2.96 mm Hg; mean difference 2.93 mm Hg; 95% confidence interval, -0.71 to 6.57 mm Hg; p = 0.12). More patients who received triamcinolone injections developed an increase in intraocular pressure > 7 mm than did those who received hyaluronic acid (29% [nine of 29] versus 0% [zero of 31]; p = 0.002). Of the nine patients who developed elevated intraocular pressure after a triamcinolone injection, five returned for reevaluation 1 month later, and four of them had pressures that remained elevated > 7 mm Hg from baseline.

CONCLUSIONS

There appears to be an associated intraocular pressure elevation found in patients who have undergone a triamcinolone injection of the knee. Further larger scale randomized investigations are warranted to determine the longevity of this pressure elevation as well as long-term clinical implications, including optic nerve damage and visual field loss.

LEVEL OF EVIDENCE

Level II, therapeutic study.

Alginate-based hydrogels functionalised at the nanoscale using layer-by-layer assembly for potential cartilage repair

Injuries to articular cartilage are frequently difficult to repair, in part because of the poor regenerative capacity of this tissue. To date, no successful system for complete regeneration of the most challenging cartilage defects has been demonstrated. The aim of this work was to develop functionalised hydrogels at the nanoscale by Layer-by-Layer (LbL) assembly to promote cartilage healing. Hydrogels, based on sodium alginate (NaAlg) and gelatin (G), were prepared by an external gelation method consisting of CaCl₂ diffusion and genipin addition for G crosslinking. Successively, hydrogels were coated with G to obtain a positive charge on the surface, then functionalised by LbL assembly to create 16 nanolayers, based on poly(styrene sulfonate)/poly(allyl amine) (PSS/PAH), including a specific peptide sequence (CTATVHL) and transforming growth factors β1 (TGF-β1). Physico-chemical properties were evaluated by XPS, ATR-FTIR and rheological analyses while in vitro cytocompatibility was studied using bovine articular chondrocytes (BAC). XPS spectra showed N_1s and S_2p peaks, indicating that PAH and PSS have been introduced with success. ATR-FTIR indicated the specific PAH and PSS absorption peaks. Finally, the biomolecule incorporation influenced positively the processes of BAC adhesion and proliferation, and glycosamynoglycan secretion. The functionalised alginate-based hydrogels described here are ideally suited to chondral regeneration in terms of their integrity, stability, and cytocompatibility.

Maternal and fetal genetic contribution to gestational weight gain

BACKGROUND

Clinical recommendations to limit gestational weight gain (GWG) imply high GWG is causally related to adverse outcomes in mother or offspring, but GWG is the sum of several inter-related complex phenotypes (maternal fat deposition and vascular expansion, placenta, amniotic fluid and fetal growth). Understanding the genetic contribution to GWG could help clarify the potential effect of its different components on maternal and offspring health. Here we explore the genetic contribution to total, early and late GWG.

PARTICIPANTS AND METHODS

A genome-wide association study was used to identify maternal and fetal variants contributing to GWG in up to 10 543 mothers and 16 317 offspring of European origin, with replication in 10 660 mothers and 7561 offspring. Additional analyses determined the proportion of variability in GWG from maternal and fetal common genetic variants and the overlap of established genome-wide significant variants for phenotypes relevant to GWG (for example, maternal body mass index (BMI) and glucose, birth weight).

RESULTS

Approximately 20% of the variability in GWG was tagged by common maternal genetic variants, and the fetal genome made a surprisingly minor contribution to explain variation in GWG. Variants near the pregnancy-specific beta-1 glycoprotein 5 (PSG5) gene reached genome-wide significance (P=1.71 × 10-8) for total GWG in the offspring genome, but did not replicate. Some established variants associated with increased BMI, fasting glucose and type 2 diabetes were associated with lower early, and higher later GWG. Maternal variants related to higher systolic blood pressure were related to lower late GWG. Established maternal and fetal birth weight variants were largely unrelated to GWG.

CONCLUSIONS

We found a modest contribution of maternal common variants to GWG and some overlap of maternal BMI, glucose and type 2 diabetes variants with GWG. These findings suggest that associations between GWG and later offspring/maternal outcomes may be due to the relationship of maternal BMI and diabetes with GWG.

Metabolic effects of Carbon Dioxide (CO2) insufflation during laparoscopic surgery: changes in pH, arterial partial Pressure of Carbon Dioxide (PaCo2) and End Tidal Carbon Dioxide (EtCO2)

BACKGROUND

Acid base alterations occur during laparoscopy with carbon dioxide insufflation. The purpose of this study was to investigate the effects of low tidal volume ventilation on acid base status during pneumoperitonium.

MATERIALS AND METHODS

30 patients undergoing laparoscopic surgery under General Anaesthesia were ventilated with tidal volume of 6 ml/kg and respiratory rate of 12 breaths/minute. Arterial blood gas analysis was done before, during and after C02 pneumoperitoneum. Arterial haemoglobin oxygen saturation by pulse oximetry (SPO2) and EtC02 were monitored continuously throughout the laparoscopy. Respiratory adjustments were done for EtCO2 levels above 60mmHg or SPO2 below 92% or adverse haemodynamic changes.

RESULTS

low tidal volume ventilation during pneumoperitoneum resulted in a significant elevation in PaCO2 (p<0.001) and a fall of pH (p <0.001), ion bicarbonate (HCO3-) (p = 0.011), and base excess (ABE) (p <0.001). A correlation was found between the EtCO2 and PaCO2 during pneumoperitoneum. Oxygenation was well maintained during pneumoperitoneum. No ventilatory adjustments were instituted on any of the patients as they maintained EtCO2 below 60mmHg throughout pneumoperitoneum.

CONCLUSION

Ventilation with low tidal volume during pneumoperitoneum causes a mixed respiratory and metabolic acidosis. EtCO2 is still a good non-invasive monitor for estimation of PaCO2 during low tidal volume ventilation during pneumoperitoneum.

Cannabinoid WIN-55,212-2 mesylate inhibits interleukin-1β induced matrix metalloproteinase and tissue inhibitor of matrix metalloproteinase expression in human chondrocytes

OBJECTIVE

Interleukin-1β (IL-1β) is involved in the up-regulation of matrix metalloproteinases (MMPs) leading to cartilage degradation. Cannabinoids are anti-inflammatory and reduce joint damage in animal models of arthritis. This study aimed to determine a mechanism whereby the synthetic cannabinoid WIN-55,212-2 mesylate (WIN-55) may inhibit cartilage degradation.

METHODS

Effects of WIN-55 were studied on IL-1β stimulated production of MMP-3 and -13 and their inhibitors TIMP-1 and -2 in human chondrocytes. Chondrocytes were obtained from articular cartilage of patients undergoing total knee replacement. Chondrocytes were grown in monolayer and 3D alginate bead cultures. Real-time polymerase chain reaction (PCR) was used to determine the gene expression of MMP-3, -13, TIMP-1 and -2 and Enzyme Linked Immunosorbent Assay (ELISA) to measure the amount of MMP-3 and MMP-13 protein released into media. Immunocytochemistry was used to investigate the expression of cannabinoid receptors in chondrocyte cultures.

RESULTS

Treatment with WIN-55 alone or in combination with IL-1β, decreased or abolished MMP-3, -13, TIMP-1 and -2 gene expression in human chondrocyte monolayer and alginate bead cultures in both a concentration and time dependent manner. WIN-55 treatment alone, and in combination with IL-1β, reduced MMP-3 and -13 protein production by chondrocytes cultured in alginate beads. Immunocytochemistry demonstrated the expression of cannabinoid receptors in chondrocyte cultures.

CONCLUSION

Cannabinoid WIN-55 can reduce both basal and IL-1β stimulated gene and protein expression of MMP-3 and -13. However WIN-55 also decreased basal levels of TIMP-1 and -2 mRNA. These actions of WIN-55 suggest a mechanism by which cannabinoids may act to prevent cartilage breakdown in arthritis.

Scotland's Knowledge Network: translating knowledge into action to improve quality of care

The Knowledge Network (www.knowledge.scot.nhs.uk) is Scotland's online knowledge service for health and social care. It is designed to support practitioners to apply knowledge in frontline delivery of care, helping to translate knowledge into better health-care outcomes through safe, effective, person-centred care. The Knowledge Network helps to combine the worlds of evidence-based practice and quality improvement by providing access to knowledge about the effectiveness of clinical interventions ('know-what') and knowledge about how to implement this knowledge to support individual patients in working health-care environments ('know-how'). An 'evidence and guidance' search enables clinicians to quickly access quality-assured evidence and best practice, while point of care and mobile solutions provide knowledge in actionable formats to embed in clinical workflow. This research-based knowledge is complemented by social networking services and improvement tools which support the capture and exchange of knowledge from experience, facilitating practice change and systems improvement. In these cases, the Knowledge Network supports key components of the knowledge-to-action cycle--acquiring, creating, sharing and disseminating knowledge to improve performance and innovate. It provides a vehicle for implementing the recommendations of the national Knowledge into Action review, which outlines a new national approach to embedding knowledge in frontline practice and systems improvement.

Atmospheric trends in methylchloroform and the global average for the hydroxyl radical

Frequent atmospheric measurements of the anthropogenic compound methylchloroform that were made between 1978 and 1985 indicate that this species is continuing to increase significantly around the world. Reaction with the major atmospheric oxidant, the hydroxyl radical (OH), is the principal sink for this species. The observed mean trends for methylchloroform are 4.8, 5.4, 6.4, and 6.9 percent per year at Aldrigole (Ireland) and Cape Meares (Oregon), Ragged Point (Barbados), Point Matatula (American Samoa), and Cape Grim (Tasmania), respectively, from July 1978 to June 1985. These measured trends, combined with knowledge of industrial emissions, were used in an optimal estimation inversion scheme to deduce a globally averaged methylchloroform atmospheric lifetime of 6.3 (+ 1.2, -0.9) years (1sigma uncertainty) and a globally averaged tropospheric hydroxyl radical concentration of (7.7 +/- 1.4) x 10(5) radicals per cubic centimeter (1sigma uncertainty). These 7 years of gas chromatographic measurements, which comprise about 60,000 individual calibrated real-time air analyses, provide the most accurate estimates yet of the trends and lifetime of methylchloroform and of the global average for tropospheric hydroxyl radical levels. Accurate determination of hydroxyl radical levels is crucial to understanding global atmospheric chemical cycles and trends in the levels of trace gases such as methane.

Chitosan/polyester-based scaffolds for cartilage tissue engineering: assessment of extracellular matrix formation

Naturally derived polymers have been extensively used in scaffold production for cartilage tissue engineering. The present work aims to evaluate and characterize extracellular matrix (ECM) formation in two types of chitosan-based scaffolds, using bovine articular chondrocytes (BACs). The influence of these scaffolds' porosity, as well as pore size and geometry, on the formation of cartilagineous tissue was studied. The effect of stirred conditions on ECM formation was also assessed. Chitosan-poly(butylene succinate) (CPBS) scaffolds were produced by compression moulding and salt leaching, using a blend of 50% of each material. Different porosities and pore size structures were obtained. BACs were seeded onto CPBS scaffolds using spinner flasks. Constructs were then transferred to the incubator, where half were cultured under stirred conditions, and the other half under static conditions for 4 weeks. Constructs were characterized by scanning electron microscopy, histology procedures, immunolocalization of collagen type I and collagen type II, and dimethylmethylene blue assay for glycosaminoglycan (GAG) quantification. Both materials showed good affinity for cell attachment. Cells colonized the entire scaffolds and were able to produce ECM. Large pores with random geometry improved proteoglycans and collagen type II production. However, that structure has the opposite effect on GAG production. Stirred culture conditions indicate enhancement of GAG production in both types of scaffold.

Hearing loss after lumbar puncture

We report a 63-year-old man who developed transient acute on chronic hearing loss after a lumbar puncture performed to investigate raised intracranial pressure. He was subsequently found to have stenosis of the distal left transverse sinus, which was treated with stenting.

Delivery of a brief motivational intervention to patients with alcohol-related facial injuries: role for a specialist nurse

In this paper we focus on providing an alcohol screening and intervention service within maxillofacial surgery. Two trained nurses screened patients with alcohol-related facial injuries who attended maxillofacial outpatient clinics, and gave brief motivational interventions to those who had been drinking to a hazardous level. Patients were followed up at 3 and 12 months after the intervention. 195/249 patients (78%) drank to a hazardous level. One hundred and ninety-five patients received an intervention. Duration of intervention was between 5 and 65 minutes. Reasons for refusal to participate included lack of interest or time, and the main reason for exclusion was length of time since injury. The follow up rate was 103 (53%) at 3 months and 134 (69%) at 12 months.

CONCLUSIONS

The high level of hazardous drinking among people with facial trauma suggests a clear need for alcohol screening and intervention. It is feasible for nursing staff to deliver brief interventions in a busy maxillofacial trauma clinic.

Influence of the extracellular matrix on the frictional properties of tissue-engineered cartilage

Low-friction surfaces are critical for efficient joint articulation. The tribological properties of articular cartilage have been studied extensively in native tissue and joints. Despite their importance, very few studies have examined the frictional properties of tissue-engineered cartilage. We have therefore reviewed the relationship between composition, structure and friction in tissue-engineered cartilage.

Short burst oxygen therapy after activities of daily living in the home in chronic obstructive pulmonary disease

BACKGROUND

Short burst oxygen therapy (SBOT) is widely prescribed in the UK with little evidence of benefit. A study was performed to examine whether SBOT benefits patients when undertaking normal activities at home among those who already use it.

METHODS

Twenty-two patients with chronic obstructive pulmonary disease (COPD) were included in the study. All regularly used SBOT at home and claimed that it helps them. Each patient chose two daily living activities for which they used SBOT for relief of breathlessness. Patients were then randomised to use either an air or oxygen gas cylinder. At least 15 min later the same activity was performed using the other gas cylinder. The same process was then repeated for the second chosen activity. The main endpoints were subjective and objective times to recovery, analysed for each activity separately or taking the average over the two activities. A paired statistical analysis was performed.

RESULTS

All patients used SBOT with nasal prongs after exercise. Using the average recovery time over two activities for each patient, the mean objective recovery time was 38 s lower (95% CI -81 to +5) using oxygen and the mean subjective recovery time was 34 s lower (95% CI -69 to +2). Five patients were correctly able to distinguish oxygen from air after both activities and there was a suggestion that their recovery times were shorter than those who did not correctly identify the gases (91 s vs 20 s using objective recovery times, and 80 s vs 22 s using subjective recovery times), although this was a subgroup analysis based on only five patients with non-significant results.

CONCLUSIONS

There is some evidence that SBOT shortens recovery time after activities of daily living in a selected group of patients with COPD, but the effect is small. There appears to be a subgroup of patients who may benefit to a much greater degree.

A cartilage tissue engineering approach combining starch-polycaprolactone fibre mesh scaffolds with bovine articular chondrocytes

In the present work we originally tested the suitability of corn starch-polycaprolactone (SPCL) scaffolds for pursuing a cartilage tissue engineering approach. Bovine articular chondrocytes were seeded on SPCL scaffolds under dynamic conditions using spinner flasks (total of 4 scaffolds per spinner flask using cell suspensions of 0.5 x 10(6) cells/ml) and cultured under orbital agitation for a total of 6 weeks. Poly(glycolic acid) (PGA) non-woven scaffolds and bovine native articular cartilage were used as standard controls for the conducted experiments. PGA is a kind of standard in tissue engineering approaches and it was used as a control in that sense. The tissue engineered constructs were characterized at different time periods by scanning electron microscopy (SEM), hematoxylin-eosin (H&E) and toluidine blue stainings, immunolocalisation of collagen types I and II, and dimethylmethylene blue (DMB) assay for glycosaminoglycans (GAG) quantification assay. SEM results for SPCL constructs showed that the chondrocytes presented normal morphological features, with extensive cells presence at the surface of the support structures, and penetrating the scaffolds pores. These observations were further corroborated by H&E staining. Toluidine blue and immunohistochemistry exhibited extracellular matrix deposition throughout the 3D structure. Glycosaminoglycans, and collagen types I and II were detected. However, stronger staining for collagen type II was observed when compared to collagen type I. The PGA constructs presented similar features to SPCL at the end of the 6 weeks. PGA constructs exhibited higher amounts of matrix glycosaminoglycans when compared to the SPCL scaffolds. However, we also observed a lack of tissue in the central area of the PGA scaffolds. Reasons for these occurrences may include inefficient cells penetration, necrosis due to high cell densities, or necrosis related with acidic by-products degradation. Such situation was not detected in the SPCL scaffolds, indicating the much better biocompatibility of the starch based scaffolds.

A case of chondromatosis indicates a synovial stem cell aetiology

OBJECTIVE

To evaluate cell cultures derived from intrasynovial nodules from a patient with primary synovial chondromatosis (PSC) for aberrant numbers/differentiation of osteochondroprogenitor cells.

METHODS

Cell cultures were established from PSC synovial nodules, or normal bovine or human osteoarthritis (OA) synovia (for comparison). Multi-lineage potential was determined using well-characterized in vitro culture systems to assess osteogenic, chondrogenic and adipogenic capability.

RESULTS

Primary PSC cell cultures were typically fibroblastic but contained islands of dense cell clusters/nodules, some of which were isolated and cultured separately [putative osteochondroprogenitris (pOCP) cultures]. OA synovial cultures had barely detectable levels of alkaline phosphatase (AP) that increased (0.006+/-0.008 to 0.141+/-0.000 nmol p-nitrophenol/min/cm(2)) with dexamethasone treatment. AP activity was higher in primary PSC cell cultures and further enhanced by dexamethasone (from 0.076+/-0.022 to 5.735+/-0.000 nmol p-nitrophenol/min/cm(2)). Histochemically, AP was localized as discreet areas within PSC cultures. No AP activity was detected histochemically in OA or normal bovine synovial cultures. The pOCP cultures had high basal AP (5.036+/-0.439 nmol p-nitrophenol/min/cm(2)) and spontaneously formed mineralized nodules, which increased in number under standard osteogenic conditions. Under chondrogenic conditions, micromass or pellet-cultured pOCP cells spontaneously synthesized a matrix containing glycosaminoglycans and collagen II. In adipogenic medium, the number of lipid-containing cells was increased.

CONCLUSIONS

Compared with cultures established from OA or normal synovia, cell cultures established from PSC synovial nodules were enriched in osteochondroprogenitors, which, unlike normal mesenchymal cells, differentiated along chondrogenic and osteogenic lineages in the absence of dexamethasone.