A Comparison of Plastic Surgery Authorship Trends Under Single Versus Double-Blinded Review

INTRODUCTION

Research is key to academic advancement in plastic surgery. However, access to publication opportunities may be inequitable as seen in other fields. We compared authorship trends of plastic surgery manuscripts that underwent single-blinded review (SBR) versus double-blinded review (DBR) to identify potential disparities in publication opportunities.

METHODS

Publications from two plastic surgery journals using SBR and two using DBR from September 2019 to September 2021 were evaluated. Name and institution of the article's first and senior author and journal's editor-in-chief (EIC) were recorded. Chi-squared and Fisher's exact analyses were used to compare author characteristics between SBR and DBR articles.

RESULTS

Of 2500 manuscripts, 65.7% underwent SBR and 34.3% underwent DBR. SBR articles had higher percentages of women as first authors (31.9% versus 24.3%, P < 0.001) but lower percentages of first (50.7% versus 71.2%, P < 0.001) and senior (49.6% versus 70.3%, P < 0.001) authors from international institutions. First (26.0% versus 12.9%, P < 0.001) and senior (27.9% versus 18.0%, P = 0.007) authors of SBR articles tended to have more plastic surgery National Institutes of Health funding. Journals using SBR tended to have higher rates of authorship by EICs or authors sharing institutions with the EIC (P ≤ 0.005).

CONCLUSIONS

While associated with greater female first authorship suggesting potential efforts toward gender equity in academia, SBR of plastic surgery articles tends to favor authors from institutions with higher National Institutes of Health funding and disadvantage authors from international or lower-resourced programs. Careful consideration of current peer-review proceedings may make publication opportunities more equitable.

Modelling the impact of reopening schools in the UK in early 2021 in the presence of the alpha variant and with roll-out of vaccination against SARS-CoV-2

Following the resurgence of the COVID-19 epidemic in the UK in late 2020 and the emergence of the alpha (also known as B117) variant of the SARS-CoV-2 virus, a third national lockdown was imposed from January 4, 2021. Following the decline of COVID-19 cases over the remainder of January 2021, the question of when and how to reopen schools became an increasingly pressing one in early 2021. This study models the impact of a partial national lockdown with social distancing measures enacted in communities and workplaces under different strategies of reopening schools from March 8, 2021 and compares it to the impact of continual full national lockdown remaining until April 19, 2021. We used our previously published agent-based model, Covasim, to model the emergence of the alpha variant over September 1, 2020 to January 31, 2021 in presence of Test, Trace and Isolate (TTI) strategies. We extended the model to incorporate the impacts of the roll-out of a two-dose vaccine against COVID-19, with 200,000 daily vaccine doses prioritised by age starting with people 75 years or older, assuming vaccination offers a 95% reduction in disease acquisition risk and a 30% reduction in transmission risk. We used the model, calibrated until January 25, 2021, to simulate the impact of a full national lockdown (FNL) with schools closed until April 19, 2021 versus four different partial national lockdown (PNL) scenarios with different elements of schooling open: 1) staggered PNL with primary schools and exam-entry years (years 11 and 13) returning on March 8, 2021 and the rest of the schools years on March 15, 2020; 2) full-return PNL with both primary and secondary schools returning on March 8, 2021; 3) primary-only PNL with primary schools and exam critical years (years 11 and 13) going back only on March 8, 2021 with the rest of the secondary schools back on April 19, 2021 and 4) part-rota PNL with both primary and secondary schools returning on March 8, 2021 with primary schools remaining open continuously but secondary schools on a two-weekly rota-system with years alternating between a fortnight of face-to-face and remote learning until April 19, 2021. Across all scenarios, we projected the number of new daily cases, cumulative deaths and effective reproduction number R until April 30, 2021. Our calibration across different scenarios is consistent with alpha variant being around 60% more transmissible than the wild type. We find that strict social distancing measures, i.e. national lockdowns, were essential in containing the spread of the virus and controlling hospitalisations and deaths during January and February 2021. We estimated that a national lockdown over January and February 2021 would reduce the number of cases by early March to levels similar to those seen in October 2020, with R also falling and remaining below 1 over this period. We estimated that infections would start to increase when schools reopened, but found that if other parts of society remain closed, this resurgence would not be sufficient to bring R above 1. Reopening primary schools and exam critical years only or having primary schools open continuously with secondary schools on rotas was estimated to lead to lower increases in cases and R than if all schools opened. Without an increase in vaccination above the levels seen in January and February, we estimate that R could have increased above 1 following the reopening of society, simulated here from April 19, 2021. Our findings suggest that stringent measures were integral in mitigating the increase in cases and bringing R below 1 over January and February 2021. We found that it was plausible that a PNL with schools partially open from March 8, 2021 and the rest of the society remaining closed until April 19, 2021 would keep R below 1, with some increase evident in infections compared to continual FNL until April 19, 2021. Reopening society in mid-April, without an increase in vaccination levels, could push R above 1 and induce a surge in infections, but the effect of vaccination may be able to control this in future depending on the transmission blocking properties of the vaccines.

528 EVALUATING THE PRESCRIPTION OF OPIATES IN PATIENTS WITH NECK OF FEMUR FRACTURES IN OUT OF HOSPITAL AND EMERGENCY CARE SETTING

Introduction

Opiate based analgesia forms a key component of Hip Fracture management. If prescribed inappropriately, opiate based analgesia can lead to respiratory depression, nephrotoxicity, and delayed recovery. The aim of this project was to evaluate opiate prescription in NOF patients in both out of hospital (OOH) and Emergency Department (ED).

Methods

100 consecutive patients were identified from National Hip Fracture Database between January and August 2019. Medical records were reviewed in both care settings, reviewing dose of morphine in comparison to body weight and renal function. Outcomes measured include constipation, acute kidney injury, respiratory compromise, and mortality. Statistical tests (t-test and chi square) were used to discern significance. Following the first cycle of results, results were disseminated to paramedics and at local governance meetings. Teaching was undertaken to increase awareness of harms associated with inappropriate opiate prescribing. A second cycle evaluated 30 consecutive NOFs from July 2020.

Results

In our study population, 74% were female and the average age was 84. The range of morphine doses given OOH ranged from 2-40 mg, in comparison to 2.5-20 mg in ED. 18% of patient suffered from Respiratory depression with 48 hours of their admission with a further 7% suffering from an acute kidney injury. After intervention, OOH morphine doses ranged between 5-10 mg, a reduction of 75% on maximum dose, with increased use of adjuvants as guided by the WHO pain ladder. No adverse outcomes were noted within 48 hours of admission.

Conclusion

Patient safety should be high on the agenda whilst caring for frail patients with Hip Fractures and opiate prescription is one of the most critical in the patient’s journey. Reducing harm by prescribing the optimal opiates helps to reduce mortality, morbidity, improve rehabilitation and patient flow within the NHS pathways. A guideline has been published to aid opiate prescription in elderly patients.

Modelling the potential impact of mask use in schools and society on COVID-19 control in the UK

As the UK reopened after the first wave of the COVID-19 epidemic, crucial questions emerged around the role for ongoing interventions, including test-trace-isolate (TTI) strategies and mandatory masks. Here we assess the importance of masks in secondary schools by evaluating their impact over September 1-October 23, 2020. We show that, assuming TTI levels from August 2020 and no fundamental changes in the virus's transmissibility, adoption of masks in secondary schools would have reduced the predicted size of a second wave, but preventing it would have required 68% or 46% of those with symptoms to seek testing (assuming masks' effective coverage 15% or 30% respectively). With masks in community settings but not secondary schools, the required testing rates increase to 76% and 57%.

Assessing the impact on pharmacists’ time by introducing a technician screening process for clinical trial prescriptions

Introduction

Various national guidance from the Lord Carter 2016 report to the NHS Long term plan have emphasised the need to transform traditional hospital pharmacy and make work streams more efficient.[1] A clinical trials pharmacist has historically validated clinical trial medicines. Whilst this is good practice for non-chemotherapy prescriptions, it is not a requirement of the Clinical Trial Regulations.[2] Interruption to validate trial prescriptions can have a negative impact on pharmacists’ duty and consequently patient outcomes. With limited data available, this issue has been highlighted by anecdotal evidence. Due to the often complex requirements associated with trials, the research team are responsible for assessing the suitability of treatment. This includes checking interactions with concomitant medication, reviewing blood results and patient counselling. The clinical aspect of the pharmacist validation is therefore removed, allowing technicians to be involved in the screening of suitable prescriptions. Much is written on technicians extending their roles in the clinical setting, but this service improvement focuses on enhancing their role within the pharmacy clinical trials department.

Aim

To evaluate the amount of pharmacists’ time saved by the introduction of technician screening of clinical trial prescriptions.

Method

A risk-based proforma was created and used by a pharmacist to assess clinical trial prescriptions for the suitability of screening by a Band 7 technician. Only prescriptions with pre-printed doses, no aseptic preparation or additional medicines, were approved for technician screening. The process of screening therefore only involves the checking of patient and prescriber details, allergy status and possibly a medication randomisation. The technicians under-went an in-house training including the screening of prescriptions under pharmacist supervision. A quantitative data collection tool was used to review the screening / validation of all nonchemotherapy clinical trial prescriptions received at two sites over a two-week period in September 2020. The data collection tool was piloted and all data was analysed using Microsoft Excel.

Results

A total of 89 prescriptions were received. 56 (63%) were eligible for technician screening, of which a suitable technician validated 50%.

Across both sites a total time of 360 minutes were spent validating/screening prescriptions including solving prescription related issues. Combining the time taken by a pharmacist to return from a clinical area and screening time consequently saved a total of 227 minutes of pharmacists’ time.

Conclusion

Distributing the workload amongst trained staff saves pharmacist’s time, which can be utilised on clinical and complex tasks. This does not eliminate the requirement of a pharmacist to validate prescriptions however; it reduces the frequency and streamlines the service. Further data collection is required to analyse the direct impact on patients’ and any changes in the number of reported errors. A limitation to the study is the lack of data prior to implementation as a comparator. Additionally, during data collection there were no suitable technicians available at one site due to the Covid-19 pandemic, resulting in only 50% of eligible prescriptions being screened by a technician. Ultimately, this does not change the outcome; enhancing technician’s roles allows pharmacists’ time to be used more efficiently.

References

1. Royal Pharmaceutical Society. Shaping Pharmacy for the future. Hospital Pharmacy: A briefing for members in England. 2017. Available at: https://www.rpharms.com/Portals/0/Hospital%20pharmacy%20briefing%20-%20final.pdf [Accessed: 11/10/20]

2. National Pharmacy Clinical Trials Advisory Group. Professional Guidance on Pharmacy Services for Clinical Trials v2.1. 2019. Available at: https://www.rpharms.com/Portals/0/RPS%20document%20library/Open%20access/Hospital%20Pharmacy%20Hub/Practice_Guidance_on_Pharmacy_Services_for_Clinical_Trials_v2.1.pdf?ver=2020-09-18-095937-733 [Accessed: 09/10/20]

Coincident molecular auxeticity and negative order parameter in a liquid crystal elastomer

Auxetic materials have negative Poisson's ratios and so expand rather than contract in one or several direction(s) perpendicular to applied extensions. The auxetics community has long sought synthetic molecular auxetics - non-porous, inherently auxetic materials which are simple to fabricate and avoid porosity-related weakening. Here, we report, synthetic molecular auxeticity for a non-porous liquid crystal elastomer. For strains above ~0.8 applied perpendicular to the liquid crystal director, the liquid crystal elastomer becomes auxetic with the maximum negative Poisson's ratio measured to date being -0.74 ± 0.03 - larger than most values seen in naturally occurring molecular auxetics. The emergence of auxeticity coincides with the liquid crystal elastomer backbone adopting a negative order parameter, QB = -0.41 ± 0.01 - further implying negative liquid crystal ordering. The reported behaviours consistently agree with theoretical predictions from Warner and Terentjev liquid crystal elastomer theory. Our results open the door for the design of synthetic molecular auxetics.

Graphene electrodes for adaptive liquid crystal contact lenses

The superlatives of graphene cover a whole range of properties: electrical, chemical, mechanical, thermal and others. These special properties earn graphene a place in current or future applications. Here we demonstrate one such application - adaptive contact lenses based on liquid crystals, where simultaneously the high electrical conductivity, transparency, flexibility and elasticity of graphene are being utilised. In our devices graphene is used as a transparent conductive coating on curved PMMA substrates. The adaptive lenses provide a + 0.7 D change in optical power with an applied voltage of 7.1 V_rms - perfect to correct presbyopia, the age-related condition that limits the near focus ability of the eye.

Selective complexation of divalent cations by a cyclic α,β-peptoid hexamer: a spectroscopic and computational study

The first report on metal binding ability of a cyclic α,β-peptoid hexamer towards a selection of metal cations is presented.

Non-universality of scaling exponents in quantum Hall transitions

We have investigated experimentally the scaling behaviour of quantum Hall transitions in GaAs/AlGaAs heterostructures of a range of mobility, carrier concentration, and spacer layer width. All three critical scaling exponents γ, κ and p were determined independently for each sample. We measure the localization length exponent to be γ ≈ 2.3, in good agreement with expected predictions from scaling theory, but κ and p are found to possess non-universal values. Results obtained for κ range from κ = 0.16 ± 0.02 to κ = 0.67 ± 0.02, and are found to be Landau level (LL) dependent, whereas p is found to decrease with increasing sample mobility. Our results demonstrate the existence of two transport regimes in the LL conductivity peak; universality is found within the quantum coherent transport regime present in the tails of the conductivity peak, but is absent within the classical transport regime found close to the critical point at the centre of the conductivity peak. We explain these results using a percolation model and show that the critical scaling exponent depends on certain important length scales that correspond to the microscopic description of electron transport in the bulk of a two-dimensional electron system.

On-chip terahertz spectroscopic techniques for measuring mesoscopic quantum systems

We present the self-aligned fabrication of on-chip devices in which waveguides, incorporating integrated photoconductive switches, are combined with two-dimensional electron systems to allow probing of the ultrafast (terahertz frequency range) properties of confined semiconductor systems, both at cryogenic temperatures and in high magnetic fields. We demonstrate the direct injection of on-chip terahertz pulses into the mesoscopic system by femtosecond, near infra-red laser excitation of in-plane photoconductive switches formed on an epitaxially grown, low-temperature GaAs layer, which is integrated monolithically with a GaAs∕AlGaAs heterostructure containing a two-dimensional electron system. Both the input and output terahertz signals of an on-chip waveguide are sampled by altering dynamically the photoconductive excitation∕detection arrangement in situ on a single device. We also demonstrate a new method for sub-Kelvin excitation and detection of on-chip terahertz frequency radiation in a (3)He∕(4)He dilution refrigerator that allows the photocurrent and detected terahertz transient to be mapped as function of the near-infrared excitation position at the emitter and the detector, respectively. Furthermore, we demonstrate transmission of terahertz transients through a two-dimensional electron system in a coplanar waveguide under magnetic field at temperatures as low as 200 mK.

Doxorubicin-loaded micelles of reverse poly(butylene oxide)-poly(ethylene oxide)-poly(butylene oxide) block copolymers as efficient "active" chemotherapeutic agents

Five reverse poly(butylene oxide)-poly(ethylene oxide)-poly(butylene oxide) block copolymers, BOnEOmBOn, with BO ranging from 8 to 21 units and EO from 90 to 411 were synthesized and evaluated as efficient chemotherapeutic drug delivery nanocarriers and inhibitors of the P-glycoprotein (P-gp) efflux pump in a multidrug resistant (MDR) cell line. The copolymers were obtained by reverse polymerization of poly(butylene oxide), which avoids transfer reaction and widening of the EO block distribution, commonly found in commercial poly(ethylene oxide)-poly(propylene oxide) block copolymers (poloxamers). BOnEOmBOn copolymers formed spherical micelles of 10-40 nm diameter at lower concentrations (one order of magnitude) than those of equivalent poloxamers. The influence of copolymer block lengths and BO/EO ratios on the solubilization capacity and protective environment for doxorubicin (DOXO) was investigated. Micelles showed drug loading capacity ranging from ca. 0.04% to 1.5%, more than 150 times the aqueous solubility of DOXO, and protected the cargo from hydrolysis for more than a month due to their greater colloidal stability in solution. Drug release profiles at various pHs, and the cytocompatibility and cytotoxicity of the DOXO-loaded micelles were assessed in vitro. DOXO loaded in the polymeric micelles accumulated more slowly inside the cells than free DOXO due to its sustained release. All copolymers were found to be cytocompatible, with viability extents larger than 95%. In addition, the cytotoxicity of DOXO-loaded micelles was higher than that observed for free drug solutions in a MDR ovarian NCI-ADR-RES cell line which overexpressed P-gp. The inhibition of the P-gp efflux pump by some BOnEOmBOn copolymers, similar to that measured for the common P-gp inhibitor verapamil, favored the retention of DOXO inside the cell increasing its cytotoxic activity. Therefore, poly(butylene oxide)-poly(ethylene oxide) block copolymers offer interesting features as cell response modifiers to complement their role as efficient nanocarriers for cancer chemotherapy.

A pilot investigation into the effects of different office chairs on spinal angles

PURPOSE

To investigate the effects of four office chairs on the postural angles of the lumbopelvic and cervical regions.

RESEARCH QUESTION

Which chair(s) produce an "ideal" spinal posture?

METHODS

An experimental same subject design was used involving healthy subjects (n = 14) who conducted a typing task whilst sitting on four different office chairs; two "dynamic" chairs (Vari-Kneeler and Swopper), and two static chairs (Saddle and Standard Office with back removed). Data collection was via digital photogrammetry, measuring pelvic and lumbar angles, neck angle and head tilt which were then analysed within MatLab. A repeated measures ANOVA with Bonferroni corrections for multiple comparisons was conducted.

RESULTS

Statistically significant differences were identified for posterior pelvic tilt and lumbar lordosis between the Vari-Kneeler and Swopper chairs (p = 0.006, p = 0.001) and the Vari-Kneeler and Standard Office chairs (p = 0.000, 0.000); and also for neck angle and head tilt between the Vari-Kneeler and Swopper chairs (p = 0.000, p = 0.000), the Vari-Kneeler and Saddle chairs (p = 0.002, p = 0.001), the Standard Office and Swopper chairs (p = 0.000, p = 0.000), and the Standard Office and Saddle chairs (p = 0.005, p = 0.001). This study confirms a within region association between posterior pelvic tilt and lumbar lordosis, and between neck angle and head tilt. It was noted that an ideal lumbopelvic position does not always result in a corresponding ideal cervical position resulting in a spinal alignment mismatch.

CONCLUSION

In this study, the most appropriate posture for the lumbopelvic region was produced by the Saddle chair and for the cervical region by both the Saddle and Swopper chairs. No chair consistently produced an ideal posture across all regions, although the Saddle chair created the best posture of those chairs studied. Chair selection should be based on individual need.

The risks of red cell transfusion for hip fracture surgery in the elderly

BACKGROUND AND OBJECTIVES

The benefits and indications for blood transfusion among surgical patients are controversial. There is evidence which suggests that blood transfusion is associated with poor clinical outcomes and risks of infection, but there are few data in the elderly population.

MATERIALS AND METHODS

Data were collected on haemoglobin concentrations and transfusions in 919 patients undergoing hip fracture repair at a university hospital over a 2-year period. 28-day and 180-day mortality were specified as primary outcomes. A composite infection outcome (chest infections, urinary tract infections and wound infections) was the main secondary outcome. Preoperative, operative and/or postoperative transfusions were the main exposure variable. Regression analyses were used to explore the associations between transfusion and outcomes, adjusting for pre-defined preoperative variables.

RESULTS

300 patients (32·6%) were transfused at least once during their admission. There was no evidence of a significant difference in either 28-day survival or 180-day survival between transfused and non-transfused hip fracture patients. The transfused group had higher adjusted composite infection rate (HR, 1·91; 95% CI, 1·41-2·59, P < 0·001) and prolonged length of stay in hospital than the non-transfused group (HR, 1·15; 95% CI, 1·07, 1·23, P < 0·001). Anaemia at the time of admission, extra capsular fracture and using walking aids in an indoor setting were preoperative variables, which predicted the need for transfusion.

CONCLUSION

Among an elderly population with hip fracture, blood transfusion was not associated with changes in mortality, but was associated with an increased rate of postoperative infection. These data add to the wider literature about adverse clinical outcomes in patients receiving blood transfusions and emphasises the need for prospective trials to evaluate the role of transfusion in the elderly.

Children's and parents' attitudes towards dentists' attire

AIM

To assess children and parental attitudes towards dental attire.

METHODS

A convenience sample of paediatric dental patients and their parents attending the Paediatric Dentistry Dept. (Leeds, UK). Data was collected using a questionnaire accompanied by a series of photographs of female and male dental students in different modes of attire.

RESULTS

100 parents with a mean age of 40.4 years (SD+/-8.8) and range 23-60 years, and 100 children with a mean age of 9.8 years (SD+/-3.5) and range 4-16 years responded. Participants preferred females in white coat and mask (15.5%) and white coat (10.5%); males in white coat and mask (11.0%), white coat and glasses (9.0%) and formal shirt (8.5%). Parents significantly preferred formal attire and children informal attire (x2=25.417, p<0.022). Comparing white coat vs paediatric coats, both parents and children ranked white coats in favour of paediatric coats (x2= 1.476, p=0.347). A highly significant difference was found between the male participants who favoured the male dental student and female participants the female dental student (x2= 30.600, p<0.000).

CONCLUSIONS

Parents favoured traditional dress as it gives an air of professionalism. Children preferred dental students in casual attire, both children and parents ranked formal white in favour of a paediatric coat. There was a highly significant difference in preference of the participants towards the sex of their dental health care provider, male participants favoured male student and females female students.

Rhinological, laryngological, oropharyngeal and other head and neck side effects of drugs

Following a previous paper in which we documented the otological side effects of drug therapy, we here review other drug side effects that ENT surgeons may encounter when dealing with patients. Although otological drug side effects such as hearing loss and tinnitus are well recognized there are many rhinological, laryngeal, oropharyngeal and other head and neck drug side effects. Our data were sourced from the British National Formulary and Electronic Medical Compendium websites.

Cowden disease: a review

Cowden disease is a genetically inherited disorder presenting with multiple hamartomatous and neoplastic lesions in various organs and tissues. We present a review of the diagnostic criteria, clinical presentation, genetics, and management of this condition.

Investigation of interleukin 10, 12 and 18 levels in patients with head and neck cancer

Head and neck squamous cell carcinoma (HNSCC) is an aggressive epithelial malignancy. It is the most common neoplasm arising in the upper aerodigestive tract.

Interleukin (IL) 12 and IL-18 are cytokines which have a major anti-tumour activity via stimulation of a T-helper type 1 (Th1) immune response. Interleukin 10, a potent antagonist of IL-12, is a cytokine which possesses immunosuppressive activity mainly produced via T-helper type 2 (Th2) cells. Studies of other types of cancer have shown that the level of IL-12 in serum or tissues is suppressed and/or the IL-10 level is increased, suggesting that there is an impaired cell-mediated anti-tumour response.

The aim of this study was to measure pre-operative serum cytokine concentrations in HNSCC patients in order to detect any changes in IL-10, IL-12 and IL-18, compared with non-tumour controls. The relationship between cytokine levels and standard clinicopathological features, including tumour site, tumour stage and presence of nodal metastasis, was also examined.

Fifty-seven patients with primary HNSCC were prospectively recruited, together with 40 non-tumour control patients with a similar age and sex distribution. Serum cytokine levels were measured using commercial quantitative enzyme-linked immunosorbent assay.

The HNSCC patients had significantly lower IL-12 levels (median; interquartile range) than controls (42.8 pg/ml, 26.2–61.6 vs 52.3 pg/ml, 37.5–113.7; p=0.018). Also, patients were more likely to have detectable IL-10 levels than were controls, as IL-10 was positive in 27/55 patients but in only 9/39 controls (p=0.011). Furthermore, IL-10 detectability varied according to primary site, being more commonly observed in hypopharyngeal and laryngeal tumours, and IL-10 was more likely to be detected with advanced tumour stage (T3 and T4). No differences in IL-18 levels were observed between patients and controls (p=0.169).

These results suggest (in agreement with studies on other solid malignancies) that HNSCC causes a significant change in the serum levels of specific Th1 and Th2 cytokines, producing an in vivo environment that is unlikely to promote an effective cell-mediated anti-tumour response.

The role of adenosine in chondrocyte death in murine osteoarthritis and in a murine chondrocyte cell line

OBJECTIVE

To investigate the role of adenosine in chondrocyte death in murine osteoarthritis (OA).

METHODS

5'-Nucleotidase (5'NT) generates adenosine. Enzyme activity was measured histochemically in normal murine and osteoarthritic STR/ort strain tibial cartilage. Adenosine-mediated cell death was investigated in MC615 chondrocyte cultures. Adenosine receptors (ARs) were assessed by reverse transcriptase polymerase chain reaction (RT-PCR). Cellular uptake of [(3)H] adenosine was measured with or without the inhibitor, nitrobenzylthioinosine (NBTI). Cell death was assessed by cell counting and DNA laddering following selective receptor stimulation, or after modulating adenosine metabolism with adenosine deaminase (ADA) or adenosine kinase (AK) inhibitors [erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA) and Iodotubericidin (Itub)], or with homocysteine (HC). Markers of apoptosis were assessed by Western blotting. Cell studies were validated by incubating normal murine knee joints in a medium containing adenosine and metabolic inhibitors. Apoptotic chondrocytes were identified with the TUNEL reaction.

RESULTS

5'NT activity in STR/ort tibial cartilage increased with development of OA, especially close to OA lesions. Adenosine induced MC615 cell death in the presence of ADA inhibition (100 microM EHNA), or 1mM HC, or both. Adenosine uptake, mediated by NBTI-sensitive adenosine transporters, was required for cell death. ARs were expressed (A2b>A2a>A1) but were not involved in mediating cell death. Cell death involved the activation of caspase-3 and DNA fragmentation and was prevented by inhibiting caspase activity. However, neither caspase-8 nor caspase-9 was detected. Adenosine+EHNA induced chondrocyte apoptosis in normal murine knee joints.

CONCLUSION

Increased adenosine production may induce chondrocyte apoptosis and play a role in OA in STR/ort mice.

Large B-cell non-Hodgkin's lymphoma presenting as a laryngeal cyst

Cystic lesions of the larynx are most commonly benign. However, we report a case of non-Hodgkin's lymphoma (NHL) of the larynx which presented as a supraglottic cyst. This form of presentation has not been previously described in the medical literature.

Otologic side effects of drugs

Otolaryngologic symptoms are common and patients presenting to the otolaryngologist will often be taking drugs for the treatment of unrelated diseases. As a doctor, one must not forget the potential of these drugs to cause otologic side effects and, in some cases, to be the cause of the presenting symptom. We performed a comprehensive search of the British National Formulary and Electronic Medical Compendium websites to classify the otologic side effects caused by drugs. Not all the data were found at both websites. We have compiled all the data together, subclassified them and produced a review of the otologic side effects of drugs, in table form.

Consent for tonsillectomy

Rulings in recent negligence cases reveal a shift towards what the 'reasonable patient' would expect in deciding the risks doctors must disclose to patients. This survey aimed to investigate whether the 'reasonable patient' and 'responsible body of medical opinion' agree about which risks should be discussed regarding tonsillectomy. Using questionnaires, surgeons were asked which of the 10 complications they routinely discussed and patients were asked how seriously they regarded these complications. The results were compared with the Test of Proportions. Most surgeons routinely mentioned otalgia, odynophagia, throat infection and re-operation. Most patients regarded potentially fatal bleeding, pneumonia and blood transfusion as very serious but only the minority of surgeons mentioned these (P < 0.001). When obtaining consent for tonsillectomy, surgeons do not routinely mention all the risks that the 'reasonable patient' would expect. The 'reasonable patient' would expect that re-operation, transfusion, pneumonia and fatal blood loss are discussed.

Chondrocyte death during murine osteoarthritis

OBJECTIVE

To determine whether chondrocyte apoptosis occurs during the progression of osteoarthritis (OA) in the STR/ort mouse model of OA.

METHODS

Serial cryostat sections were cut (10 microns) through the knee joint of young and old male STR/ort mice and graded for the severity of OA lesions. Age- and sex-matched CBA mice were used as controls. Apoptotic chondrocytes were detected using the TUNEL assay. Ultrastructural changes were examined using electron microscopy (EM). Expression of biochemical markers associated with apoptosis (bax, bcl-2 and caspases-3, -8 & -9) was investigated using immunohistochemistry.

RESULTS

TUNEL assays on histological sections of STR/ort knee joints showed that the number of TUNEL-positive chondrocytes in the tibial medial articular cartilage correlated with the severity of the OA damage. These cells were located close to the lesional area. Only very occasional TUNEL positive chondrocytes were detected in either morphologically normal STR/ort cartilage or in control CBA cartilage. Ultrastructural analysis of chondrocytes neighboring focal osteoarthritic lesions in STR/ort tibial cartilage revealed an abundance of abnormal cells exhibiting numerous morphological changes. These resembled, but in some cases differed, from changes reported in classical apoptosis. The changes include abnormal distribution of chromatin, cell shrinkage, membrane blebbing and deposition of cell remnants (apoptotic bodies) in the lacuna space. Despite the TUNEL and EM changes, immunohistochemistry failed to detect any changes in the ratio of bax to bcl-2 in tibial chondrocytes of STR/ort mice. Both bcl-2 and bax levels decreased with age in morphologically normal STR/ort and control CBA cartilage. None of the caspases tested for was detected in tibial chondrocytes of either strain.

CONCLUSION

Chondrocyte cell death is correlated with the progression of OA in STR/ort mice and has many of the morphological characteristics of classical apoptosis. Absence of changes in bax to bcl-2 ratio in STR/ort chondrocytes indicate that the mitochondrial pathway of apoptosis is unlikely to be involved. Failure to detect caspases could be due to low levels of enzyme expression, expression within a very brief time period, or to a caspase-independent mechanism of cell death.

The DNA sequence and comparative analysis of human chromosome 20

The finished sequence of human chromosome 20 comprises 59,187,298 base pairs (bp) and represents 99.4% of the euchromatic DNA. A single contig of 26 megabases (Mb) spans the entire short arm, and five contigs separated by gaps totalling 320 kb span the long arm of this metacentric chromosome. An additional 234,339 bp of sequence has been determined within the pericentromeric region of the long arm. We annotated 727 genes and 168 pseudogenes in the sequence. About 64% of these genes have a 5' and a 3' untranslated region and a complete open reading frame. Comparative analysis of the sequence of chromosome 20 to whole-genome shotgun-sequence data of two other vertebrates, the mouse Mus musculus and the puffer fish Tetraodon nigroviridis, provides an independent measure of the efficiency of gene annotation, and indicates that this analysis may account for more than 95% of all coding exons and almost all genes.

The spatial and temporal expression of calretinin in developing rat molars (Rattus norvegicus)

Calretinin is a 29-kDa calcium-binding protein abundantly expressed in central and peripheral neural tissues. The aim here was to determine its expression during various stages of odontogenesis. Five categories of embryonic (E) and postnatal (P) rats at various ages (E17, E18, E20, P0, and P7), both male and female, were used to represent the various stages of molar tooth development. The heads of the experimental animals were harvested at the appropriate time and each was cut mid-sagittally and coronally to locate the tooth germs. Selected sections were stained immunohistochemically with polyclonal rabbit anticalretinin at a concentration of 1:25 after microwave irradiation. The results showed that calretinin is distributed widely in epithelium-derived tissues during odontogenesis in rat molar tooth germs. It was expressed focally in the dental lamina, outer enamel epithelium, stellate reticulum and stratum intermedium at different stages. In contrast, it was expressed diffusely and intensely in the inner enamel epithelium and presecretory ameloblasts, although it was discontinuous over the cusp tips. In the secretory ameloblasts, the staining was less intense, being restricted to the cytoplasm, including Tomes' processes. This distribution suggests that calretinin may play a part in enamel formation.

The physical maps for sequencing human chromosomes 1, 6, 9, 10, 13, 20 and X

We constructed maps for eight chromosomes (1, 6, 9, 10, 13, 20, X and (previously) 22), representing one-third of the genome, by building landmark maps, isolating bacterial clones and assembling contigs. By this approach, we could establish the long-range organization of the maps early in the project, and all contig extension, gap closure and problem-solving was simplified by containment within local regions. The maps currently represent more than 94% of the euchromatic (gene-containing) regions of these chromosomes in 176 contigs, and contain 96% of the chromosome-specific markers in the human gene map. By measuring the remaining gaps, we can assess chromosome length and coverage in sequenced clones.

Effect of coupling medium temperature on rate of intramuscular temperature rise using continuous ultrasound

OBJECTIVE

We determined the effects of coupling medium temperature on the rate of intramuscular temperature rise (RTR) during continuous ultrasound.

DESIGN AND SETTING

Ultrasound was applied in a continuous mode at a frequency of 1 MHz and intensity of 1.5 W/cm(2). Each subject received 3 treatments, using water-based coupling gel at temperatures of 18 degrees C, 25 degrees C, and 39 degrees C. All treatments were performed in an athletic training room under controlled environmental conditions.

SUBJECTS

Eighteen healthy male subjects (mean age = 23.6 +/- 3.5 years; height = 177.8 +/- 6.9 cm; weight = 76.6 +/- 8.2 kg; calf size = 37.6 +/- 2.4 cm) participated in this study.

MEASUREMENTS

A thermistor was inserted into the left medial triceps surae at a depth of 5 cm, and baseline tissue temperatures were recorded before treatment. Intramuscular temperature was recorded every 30 seconds until the temperature rose 4 degrees C above baseline or until discomfort was felt. RTR was calculated by dividing the absolute temperature change by treatment time.

RESULTS

A 1-way, repeated-measures analysis of variance revealed a significant difference in RTR among gel temperatures, RTR was significantly faster using the 25 degrees C gel compared with the 18 degrees C and 39 degrees C gels. There was no difference between the 18 degrees C and 39 degrees C gel treatments.

CONCLUSIONS

These results suggest that the use of a cooled or heated gel may be counterproductive when maximal thermal effects are desired within a given time frame.

Protein kinase C co-expression and the effects of halothane on rat skeletal muscle sodium channels

1. Voltage-gated Na channels, which are potential targets for general anaesthetics, are substrates for PKC, which phosphorylates a conserved site in the channel inactivation gate. We investigated the idea that PKC modulates the effect of volatile anaesthetics on Na channels via phosphorylation of this inactivation gate site. 2. Na currents through rat skeletal muscle Na channel alpha-subunits expressed in Xenopus oocytes were measured by two-microelectrode voltage clamp in the presence of the volatile anaesthetic agent halothane (2-bromo-2-chloro-1,1,1-trifluroethane). PKC activity was modulated by co-expression of a constitutively active PKC alpha-isozyme. 3. Halothane (0.4 mM) had no effect on Na currents. With co-expression of PKC, however, halothane dose-dependently enhanced the rate of Na current decay and caused a small, but statistically significant reduction in Na current amplitude. 4. The enhancement of Na current decay was absent in a Na channel mutant in which the inactivation gate phosphorylation site was disabled. Effects of halothane on amplitude were independent of this mutation. 5. Co-expression of a PKC alpha-isozyme permits an effect of halothane to hasten current decay and reduce current amplitude, at least in part through interaction with the inactivation gate phosphorylation site. We speculate that the interaction between halothane and Na channels is direct, and facilitated by PKC activity and by phosphorylation of a site in the channel inactivation gate.

Temperature changes in deep muscles of humans during upper and lower extremity exercise

OBJECTIVE

To examine the effect of 15 minutes of upper and lower extremity exercise on raising intramuscular temperature in the triceps surae to 39 degrees C to 45 degrees C (the therapeutic range).

DESIGN AND SETTING

Intramuscular temperature was measured 5 cm deep in the triceps surae using a 23-gauge thermistor needle microprobe connected to a monitor. Each subject was tested under 3 conditions: 15 minutes of rest, 15 minutes of jogging on a treadmill, and 15 minutes of handpedaling an upper-body ergometer. Exercise bouts were performed at 70% of each subject's maximum heart rate.

SUBJECTS

Six males, either sedentary or recreational athletes (age = 21.3 +/- 2.9 years; ht = 176.8 +/- 6.0 cm; wt = 72.7 +/- 11.6 kg; resting heart rate = 57.8 +/- 6.74 bpm; target heart rate = 156.5 +/- 3.0 bpm), volunteered to participate in this experiment.

MEASUREMENTS

Intramuscular temperature was measured at a depth of 5 cm before and after each test condition.

RESULTS

Data analyses consisted of analyses of variance with repeated measures and a Tukey post hoc test (P < .05). The results showed a significant temperature increase over baseline after exercise on the treadmill (2.2 degrees C +/- 0.63 degrees C); however, it did not yield temperature increases >/= 39 degrees C. No significant temperature change occurred after exercise on the upper-body ergometer (-0.45 degrees C +/- 0.80 degrees C).

CONCLUSIONS

Active exercise increased intramuscular temperature in working muscles but did not affect intramuscular temperature in nonworking muscles. In addition, 15 minutes of jogging on a treadmill at 70% of maximum heart rate was not sufficient to raise intramuscular temperature to 39 degrees C to 45 degrees C.

The internal oblique repair of abdominal bulges secondary to TRAM flap breast reconstruction

The internal oblique repair, a new method for repair of abdominal bulging following TRAM flap breast reconstruction, involves identification and repair of the internal oblique fascia. To assess the usefulness of this repair and to compare it with simple plication of the deep abdominal fascia, we retrospectively reviewed all abdominal bulge repairs performed by the first author over the past 7 1/2 years. Of 30 abdominal bulge repairs, the internal oblique repair was used in 14 patients and plication in 16 others. The bulge recurrence rate was lower after the internal oblique repair (21 percent) than after the plication repair (69 percent; p = 0.028). When synthetic mesh reinforcement was added to the internal oblique repair, the bulge recurrence rate dropped to 13 percent. We conclude that the internal oblique repair is the preferred technique for the correction of abdominal bulges secondary to TRAM flap breast reconstruction.

Quantitative analysis of collagen accumulation during protein malnutrition

It is generally believed that protein malnutrition is detrimental to proper wound healing. However, there is limited evidence in the literature to support this. The authors studied the effect of protein depletion on the accumulation of collagen to determine the quantitative changes taking place in the healing wound. Polytetrafluoroethylene (PTFE) wound cylinders were implanted subcutaneously in 30 male Sprague-Dawley rats. The rats were divided into two groups and fed either chow (C) (n = 12) or an isocaloric protein-free (PF) diet (n = 18). Seven, 14, and 21 days later, the rats were weighed, bled, and wound cylinders harvested. PTFE cylinder collagen content, hematologic parameters, total serum protein, and serum albumin were determined. The rats with the PF diet had significant (P < .001) weight loss at all time-points (day 7, PF = 176.2 +/- 3.2, F = 252.4 +/- 3.8; day 14, PF = 154.8 +/- 3.6, F = 289.3 +/- 9.2; day 21, PF = 150.8 +/- 3.9, F = 307.6 +/- 12.2). Total serum protein was also depleted as compared with controls (P < .001). White blood cell counts were significantly higher on day 7 (PF = 7.5 +/- 0.9, C = 4.4 +/- 0.9, P < .03) in the PF group; however, this was not sustained, and there was no difference between the groups on days 14 and 21. Collagen content (micrograms of 5-hydroxyproline [OHP] per centimeter PTFE) was diminished on day 7 (PF = 12.7 +/- 2.0, C = 24.7 +/- 3.4, P < .03). No difference was seen on day 14.(ABSTRACT TRUNCATED AT 250 WORDS)

Differential acceleration of healing of surgical incisions in the rabbit gastrointestinal tract by platelet-derived growth factor and transforming growth factor, type beta

Anastomotic dehiscence is a major cause of morbidity and mortality in gastrointestinal surgery. A unique model system of a gastric incision was developed to test the potential of polypeptide growth factors to enhance wound healing. Paired, deep partial-thickness incisions to but not including the gastric mucosa were made. A single topical application of transforming growth factor, type beta 1 (TGF-beta), platelet-derived growth factor, or control vehicle at the time of wounding was given. Wound breaking strength and detailed histologic analyses of wounds were evaluated as a function of time after wounding. TGF-beta (0.1 to 2.0 micrograms/wound) demonstrated a bimodal, dose-dependent acceleration of wound breaking strength 7 days after gastric wounding. An approximate 4-day acceleration of gastric wound breaking strength by TGF-beta (2 micrograms/wound) was seen at 7 and 11 days. Wounds treated with platelet-derived growth factor (10 micrograms/wound) displayed an increased cellular response but no enhancement of breaking strength at 7 and 11 days. These results demonstrate the ability of TGF-beta to accelerate gastrointestinal tissue repair by topical application and suggest significant potential for the use of growth factors in enhancing repair of surgical wounds of the gastrointestinal tract.

Organ culture studies of human prostatic adenocarcinomas

The proliferative responses of human prostatic carcinoma have been evaluated in organ culture using [125I]-iododeoxyuridine ([125I]UdR) to monitor DNA synthesis. The morphological preservation was not influenced by the addition of fetal calf serum or insulin (5 mu gm/ml), transferrin (10 mu gm/ml), and thyrotropin releasing hormone (10(-9) M) to the active medium. Testosterone (4 X 10(-7) M) stimulated [125I]UdR uptake, whereas diethylstilboestrol (4 X 10(-6) M) had no direct effect on uptake. Both estramustine phosphate (4 X 10(-6) M) and oestradiol-17 beta (4 X 10(-6) M) inhibited uptake in a similar manner. Thus while explants of human prostatic carcinoma derived from transurethrally resected specimens can be well maintained in organ culture for a few days, proliferative responses are small and difficult to measure for individual patients.

Proliferative responses of cultured rat prostate and human benign prostatic hyperplasia

The proliferative responses of rat prostate and human benign prostatic hyperplasia have been followed in organ culture using [125I] iododeoxyuridine uptake to monitor DNA synthesis. In serum-free cultures, testosterone induced a marked increase in DNA synthesis (three-fold) in 4- to 6-month-old rat prostates at concentrations of 4 x 10(-9) to 4 x 10(-6) M, whereas in greater than 12-month-old rat prostates the response was less marked. Human benign prostatic hyperplasia also showed an increased uptake at similar testosterone concentrations and of a similar magnitude to the response of greater than 12-month-old rat prostates. At 10(-5) M DNA synthesis was markedly suppressed in cultures of both rat and human prostate. The proliferative response of human benign prostatic hyperplasia increases up to days 3 to 4 in culture and then declines in both control and hormone-treated groups and may represent repair processes which appear to be hormone dependent.