Superior Capsule Reconstruction With Fascia Lata Allograft Has Initial Stiffness and Ultimate Load Comparable to the Native Shoulder Superior Capsule: A Cadaveric Biomechanical Study

PURPOSE

The purpose of this study was to compare the biomechanical characteristics of a fascia lata superior capsule reconstruction (FL-SCR) to the native superior capsule.

METHODS

The native superior capsule of 8 cadaveric shoulders was tested with cyclic loading from 10 to 50 N for 30 cycles in 20° of glenohumeral abduction followed by load to failure at 60 mm/min. Following native superior capsule testing, FL-SCR was performed, which was tested as described for the native capsule. Paired t test was used for statistical analyses with P < .05 for significance.

RESULTS

The stiffness for cycle 1 to 50 N was significantly higher for the native superior capsule compared to the FL-SCR (P = .001). By cycle 30, the stiffness between the two was not statistically different (P = .734). During load to failure, the initial stiffness to 2 mm for the FL-SCR and the native superior capsule was not statistically different (P = .262). The linear stiffness and yield load of the native superior capsule were significantly greater than that of the FL-SCR (94.5 vs 28.0 N/mm, P = .013; 386.9 vs 123.8 N, P = .029). There was no significant difference in ultimate load between the native superior capsule and the FL-SCR (444.9 vs 369.0 N, P = .413).

CONCLUSIONS

FL-SCR has initial stiffness and ultimate load similar to the native superior capsule.

CLINICAL RELEVANCE

The biomechanical properties of FL allograft make it an appealing option as a graft choice for superior capsule reconstruction.

Off-Season Arthroscopic Partial Meniscectomy in National Collegiate Athletic Association Division I Football Players Has a Longer Return to Sport Time than In-Season Surgery

Purpose

To report the outcomes of routine arthroscopic meniscectomy in National Collegiate Athletic Association (NCAA) Division I Football players.

Methods

NCAA athletes who underwent arthroscopic meniscectomy over 5 years were included. Players who had incomplete data, previous knee surgery, ligamentous injury, and/or microfractures were excluded. Data collected were player position, timing of surgery, procedures performed, return to play (RTP) rate and time, and postoperative performance. Continuous variables were analyzed with Student t-tests or a one-way analysis of variance.

Results

Thirty-six athletes (38 knees) who underwent arthroscopic partial meniscectomy (31 lateral, 7 medial) were included. The mean RTP time was 71 ± 39 days. The mean RTP time in athletes who underwent in-season surgery) was significantly shorter than the RTP in athletes who had off-season surgery (58 ± 41 days vs 85 ± 33 days, P < .05). The mean RTP in 29 athletes (31 knees) with lateral meniscectomy was similar to the 7 athletes (7 knees) who had medial meniscectomy (70 ± 36 vs 77 ± 56, P = .6803). The mean RTP time was similar between football players who underwent isolated lateral meniscectomy and those who had lateral meniscectomy with chondroplasty (61 ± 36 days vs 75±41 days, P = .32). Athletes played an average of 7.7 ± 4.9 games the season they returned; position category and anatomical compartment of the knee lesion had no bearing on number of games played (P = .1864 and P = .425).

Conclusions

NCAA Division 1 football players who underwent arthroscopic partial meniscectomy RTP at approximately 2.5 months' postoperatively. Athletes who underwent off-season surgery had longer RTP time compared with those who underwent in-season surgery. RTP time and performance after surgery did not differ based on player position, anatomical location of the lesions, or chondroplasty at the time of meniscectomy.

Level of Evidence

Level IV, therapeutic case series.

Intimate Partner Violence, Sexual Assault, and Child Abuse Resource Utilization During COVID-19

Introduction

Key measures in preventing spread of the virus that causes coronavirus disease 2019 (COVID-19) are social distancing and stay-at-home mandates. These measures along with other stressors have the potential to increase incidences of intimate partner violence (IPV), sexual assault, and child maltreatment.

Methods

We performed a retrospective review of county police dispatches, emergency department (ED) visits, Sexual Assault Nurse Examiner (SANE) consults, Domestic Violence Healthcare Project (DVHP) team consults, and Child Protection Team consults at a large, tertiary, Level I trauma center. We queried International Classification of Diseases Revision 10 codes most specific to IPV, sexual assault, and child maltreatment from March–October 2020 compared to 2019. Similarly, the number of consults performed by SANE, DVHP, and our Child Protection Team were collected. We compared all ED visits and consultations to total ED visits for the reviewed time period. Finally, the total number of calls and referrals to a child advocacy center and resource call line for victims were recorded during this timeframe.

Results

Police dispatches for IPV-related assaults increased by 266 reports from 2019 to 2020 (P = 0.015). Emergency department visits related to IPV increased from 0.11% of visits in 2019 to 0.15% in 2020 (P = 0.032), and DVHP consults increased from 0.31% in 2019 to 0.48% in 2020 of ED visits in the first three months (P < 0.001). Child maltreatment visits increased from 0.47% of visits in 2019 to 0.81% of visits in 2020 (P = 0.028), and a higher percentage of patients required Child Protection team consults from 1% in 2019 to 1.6% in 2020 (P = 0.004). Sexual assault-related visits and SANE consults both showed a small increase that was not statistically significant. Fewer calls and referrals were made to our child advocacy center and resource call line, decreasing by 99 referrals and 252 calls, respectively.

Conclusion

Despite decreased ED volumes throughout the pandemic, we observed an increase in police dispatches, ED visits, and utilization of hospital consult services related to IPV and child maltreatment following the initiation of stay-at-home orders. However, use of community resources, such as the local child advocacy center, declined.

951 SETTING UP A GERIATRIC LIAISON SERVICE WITHIN UROLOGY IN A DISTRICT GENERAL HOSPITAL

Introduction

One might refer to urologists as the ‘hidden providers’ of geriatric care, ultimately sought out by many geriatric patients. POPS, the Peri-Operative care of Older People’s Service started at Guys Hospital in London is often quoted as the gold standard for liaison services. Having set up liaison services in Orthopaedics and General Surgery in my previous job, an exciting opportunity arose after the first COVID—19 wave when I found my new office directly under the Urology Assessment Unit.

Method

A Geriatric Urology liaison service was set up by a Consultant Geriatrician with SpR support. One hour per week was agreed within the department to pilot the service. By May 2021 the service had been running for 8 months. During this period 30 patients had been seen (36 patient visits).

Results

The patient’s mean age was 82 years. The advice given included: O Stopping medication (7 cases) O Recommending iron infusions instead of tablets (5 cases) O Adjusting analgesia (4 cases) O Ordering brain imaging (3 cases) Commonly there was the recognition of the need for palliative care in this frail population. There have been complex cases: O A gentleman with a large perinephric bleed. O A young man with seizures and cognitive issues following renal stones. O A patient with post-operative rhabdomyolysis following nephrectomy. Pre-operative assessments have now been started as part of enhanced care: O Two cystectomy patients (one ward/one telephone) O Two TURBT patients (one with low sodium).

Conclusion

Staff feedback has been excellent especially linking to the Palliative Care Team. We presented our data at the Urology governance meeting in September 2021 and again received excellent feedback. The urology staff have felt increasingly supported. Data collection has helped build a business case for two Consultant posts in surgical liaison.

POS1304 CORRELATION OF SKIN SCORES (LoSCAT) WITH PATIENT REPORTED OUTCOMES IN JUVENILE LOCALISED SCLERODERMA

Background

Juvenile localised scleroderma (JLS) or morphea is a rare condition, causing inflammation and fibrosis in skin and underlying tissues. A validated skin score (Localized Scleroderma Cutaneous Assessment Tool, LoSCAT) has been developed [1]. This tool has both activity (mLoSSi) and damage indices (LoSDI). Several patient-reported outcomes (PRO) have been studied in JLS including visual analogue scales (VAS), functional and health-related quality of life measures.

Objectives

To assess the associations between different PROs and the activity and damage indices of the LoSCAT.

Methods

Participants aged 4 to 17 were recruited from 3 tertiary paediatric rheumatology centres in the UK and attended 4 visits at 3 monthly intervals as part of a program of research on JLS. Patient-reported VAS (6 different scales), the Children’s Dermatology Life Quality Index (CDLQI) and Childhood Health Assessment Questionnaires (CHAQ) were completed at each visit. LoSCAT was completed by the two same clinicians throughout the study (both trained in skin score techniques). Pearson correlation coefficients were calculated between each PRO and each component of the LoSCAT.

Results

24 participants completed all 4 visits and 1 attended 3 visits. 20 participants were female (80%) and 5 were male (20%). Mean age at diagnosis was 7.6 years with mean disease duration of 4.9 years. Subtype of disease was linear head in 5/25 (20%), linear limb 12/25 (48%), generalised morphoea 1/25 (4%), mixed 5/25 (20%) and superficial plaque in 2/25 (8%). Table 1 shows the correlations with figures in bold highlighting positive correlations which were statistically significant (p<0.05) and medium-sized (r>0.3).

Table 1.

Correlation between patient reported outcomes and LoSCAT

PROTotal skin activity (mLoSSi)Total skin damage (LoSDI)r (95% CI)p-valuer (95% CI)p-valueCDLQI0.61 (0.02, 1.20)0.0440.42 (0.01, 0.83)0.044CHAQ0.30 (0.03, 0.57)0.0270.20 (-0.14, 0.54)0.244VAS 1: How much IMPACT has your disease had on your life in the PAST MONTH?0.49 (0.00, 0.98)0.0500.38 (0.06, 0.71)0.021VAS 2: How much has your condition (localized scleroderma) affected you OVERALL in the PAST MONTH?0.59 (0.09, 1.09)0.0220.42 (0.13, 0.72)0.005VAS 3: Have your lesions felt itchy and/or scratchy in PAST MONTH?0.40 (-0.01, 0.81)0.0560.31 (0.03, 0.59)0.028VAS 4: Have you felt numbness, tingling, and/or other “funny” feeling in or around your lesion in PAST MONTH?0.55 (0.04, 1.05)0.0330.33 (-0.04, 0.71)0.084VAS 5: How much WORRY do you have about LONG- -TERM problems from your disease?0.40 (-0.01, 0.81)0.0530.32 (0.00, 0.63)0.047VAS 6: How much WORRY do you have about problems from MEDICATIONS used to treat your condition?0.41 (0.00, 0.82)0.0500.29 (-0.09, 0.66)0.131

The VAS of symptoms of numbness/tingling showed a strong positive correlation with mLoSSi but a weak and/or non-significant correlation with LoSDI. VAS itchy/scratchy did not show a strong correlation with mLoSSi but showed a moderate correlation with LoSDI. Patient global VAS correlated with both mLoSSi and LoSDI, as did CDLQI. CHAQ correlated with activity only.

Conclusion

Symptoms within lesions are often interpreted as indicating disease activity. A previous study in adults and children showed itch positively correlated with mLoSSi suggesting it may be a marker of active disease [2]. However, in our study numbness/tingling correlated with disease activity whereas itch did not. Further work is required to understand whether itch correlates to both activity and damage and whether numbness/tingling is a better indicator of activity than itch. Limitations of our study include a heterogenous group of participants with longstanding high-burden disease.

References

[1]Arkachaisri et al. Rheumatology 2010. 49(2): 373-81.

[2]Klimas et al. Br J Derm 2015; 175:1329-1337

Acknowledgements

This study was funded by Scleroderma & Raynaud’s UK.

Disclosure of Interests

None declared

POS0168 NON-INVASIVE IMAGING IN JUVENILE LOCALISED SCLERODERMA: HIGH-FREQUENCY ULTRASOUND, THERMOGRAPHY, LASER DOPPLER & MULTISPECTRAL IMAGING

Background

Outcome measures which can differentiate activity (inflammation) from damage (fibrosis/atrophy) would facilitate development of new treatment strategies in juvenile localized scleroderma (JLS) to target the inflammatory phase of the disease.

Objectives

To evaluate whether in JLS, non-invasive imaging modalities (high frequency ultrasounds (HFUS), multispectral imaging (MSI), laser doppler imaging (LDI) & infra-red thermography (IRT)) can detect differences between affected & non-affected skin, as a next step in developing these as outcome measures. Our hypothesis was that blood flow (and therefore temperature & oxygenation) would be increased in lesional skin.

Methods

Participants aged 4-17 were recruited from 3 paediatric rheumatology centres in the UK. For each participant, a single lesion was selected. HFUS (30MHz), MSI (bespoke camera and tuneable liquid crystal filter, coupled to custom analysis software, 500nm/710nm wavelengths), LDI and IRT imaging were performed at four sites relating to each lesion: two of affected skin (centre & inner edge of lesion) and two of non-affected skin (one cm from edge of lesion (‘outer’) & contralateral unaffected side). Imaging was performed at 4 visits at 3 monthly intervals. Mean values were compared between the four sites using data from all visits by mixed-effects linear regression to account for individual-level clustering.

Results

24 participants completed all 4 visits and 1 attended 3. 20 participants were female (80%) & 5 male (20%). Mean age at diagnosis was 7.6 years & disease duration 4.9 years. Subtype of disease was linear head in 5/25 (20%), linear limb 12/25 (48%), generalised morphea 1/25 (4%), mixed 5/25 (20%) and superficial plaque in 2/25 (8%).

Table 1 shows a subset of data. All 4 imaging techniques could detect differences between healthy (outer/contralateral) & affected skin (centre/inner edge). For HFUS, there was strong evidence of a difference between affected & unaffected skin (p<0.001) indicating affected skin is thinner than unaffected. Higher mean values of oxygenation, perfusion & temperature were observed in affected compared to non-affected skin in MSI, LDI and IRT respectively. There was no statistical difference seen between inner edge and centre of the lesion in any of the methods.

Table 1.

Mean differences between different locations for each imaging technique

Imaging techniqueLocationOverall mean difference (95% CI)p-valueHFUS (mm)Centre - Contralateral-0.34 (-0.46, -0.22)<0.001Inner edge - Contralateral-0.30 (-0.40, -0.20)<0.001Centre - Outer-0.35 (-0.46, -0.24)<0.001Inner edge - Outer-0.31 (-0.40, -0.21)<0.001Centre - Inner edge-0.04 (-0.10, 0.02)0.168MSI (rel units)Centre - Contralateral0.06 (0.03, 0.10)<0.001Inner edge - Contralateral0.06 (0.03, 0.09)<0.001Centre - Outer0.04 (0.01, 0.07)0.012Inner edge - Outer0.03 (0.00, 0.06)0.028Centre - Inner edge0.01 (0.00, 0.02)0.251LDI Relative perfusion unitsCentre - Contralateral44.8 (24.4, 65.2)<0.001Inner edge - Contralateral47.9 (21.0, 74.8)<0.001Centre - Outer19.1 (1.0, 37.1)0.039Inner edge - Outer24.8 (6.7, 42.9)0.007Centre - Inner edge-3.5 (-20.3, 13.2)0.679IRT oCCentre - Contralateral0.58 (0.24, 0.91)0.001Inner edge - Contralateral0.44 (0.13, 0.75)0.005Centre - Outer0.44 (0.22, 0.66)<0.001Inner edge - Outer0.30 (0.09, 0.52)0.006Centre - Inner edge0.14 (-0.05, 0.32)0.153

The overall mean difference is the measurement of the first location minus the measurement from the second location (e.g. centre minus contralateral), averaged across the four visits.

Conclusion

Our results suggest non-invasive imaging can detect differences between healthy & unaffected skin in JLS. Whether each technique is only measuring activity & not damage requires further evaluation. The leading edge of lesions has historically been considered as most active compared to the centre. However, no difference was seen between centre & inner edge measurements suggesting that in future studies, imaging protocols can be simplified.

Acknowledgements

This study was funded by Scleroderma & Raynaud’s UK.

Disclosure of Interests

None declared

CD2-negative lymphoma-associated T-cells: a potential mechanism of immune-evasion in diffuse large B-cell lymphoma

CD2 is a costimulatory protein expressed in all mature T/NK-cells, in particular memory T-cells. CD58 (or LFA-3) is the receptor for CD2 and is ubiquitously expressed. CD2-CD58 interaction has key functions in T-cell activation and organization of the immunological synapse between T- and antigen-presenting cells. Cancer cells have developed multiple mechanisms to evade immune surveillance. Loss of CD58 expression is one frequently reported in diffuse large B-cell lymphomas (DLBCL). On the other hand, in non-hematological neoplasms, tumor infiltrating lymphocytes (TILs) with reduced expression of CD2 have been associated with defective cytotoxicity and T-cell exhaustion. Here, we reported a case of DLBCL involving the jejunal mucosa associated with a rim of cytotoxic reactive T-cells with features of immune evasion (CD2- and TCR-) and T-cell exhaustion (PD1 + high). This case likely exemplifies a previously unrecognized immune evasion mechanism in lymphoma involving a decreased CD2 expression in the lymphoma-associated T-cells.

Understanding the Associations of Prenatal Androgen Exposure on Sleep Physiology, Circadian Proteins, Anthropometric Parameters, Hormonal Factors, Quality of Life, and Sex Among Healthy Young Adults: Protocol for an International, Multicenter Study

Background

The ratio of the second finger length to the fourth finger length (2D:4D ratio) is considered to be negatively correlated with prenatal androgen exposure (PAE) and positively correlated with prenatal estrogen. Coincidentally, various brain regions are sensitive to PAE, and their functions in adults may be influenced by the prenatal actions of sex hormones.

Objective

This study aims to assess the relationship between PAE (indicated by the 2D:4D ratio) and various physiological (sex hormone levels and sleep-wake parameters), psychological (mental health), and sexual parameters in healthy young adults.

Methods

This study consists of two phases. In phase 1, we will conduct a survey-based study and anthropometric assessments (including 2D:4D ratio and BMI) in healthy young adults. Using validated questionnaires, we will collect self-reported data on sleep quality, sexual function, sleep chronotype, anxiety, and depressive symptoms. In phase 2, a subsample of phase 1 will undergo polysomnography and physiological and genetic assessments. Sleep architecture data will be obtained using portable polysomnography. The levels of testosterone, estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, prolactin, melatonin, and circadian regulatory proteins (circadian locomotor output cycles kaput [CLOCK], timeless [TIM], and period [PER]) and the expression levels of some miRNAs will be measured using blood samples. The rest and activity cycle will be monitored using actigraphy for a 7-day period.

Results

In Poland, 720 participants were recruited for phase 1. Among these, 140 completed anthropometric measurements. In addition, 25 participants joined and completed phase 2 data collection. Recruitment from other sites will follow.

Conclusions

Findings from our study may help to better understand the plausible role of PAE in sleep physiology, mental health, and sexual quality of life in young adults.

International Registered Report Identifier (IRRID)

DERR1-10.2196/29199

Temperature response to cold challenge and mobile phone thermography as outcome measures for systemic sclerosis-related Raynaud's phenomenon

Objectives: Objective outcome measures of systemic sclerosis (SSc)-related Raynaud's phenomenon (RP) are badly needed. Our objectives were to validate the thermographic response to a standard hand cold challenge as an outcome measure by assessing sensitivity to change, and to explore mobile phone thermography as a feasible, ambulatory tool.Method: Twelve patients with an SSc-spectrum disorder admitted for intravenous iloprost infusions underwent a standard cold challenge before and after one infusion. Thermographic measurements included area under the rewarming curve (AUC) and maximum rewarming temperature (MAX). Before and during another infusion, each patient underwent monitoring of finger skin temperature by two methods: continuous thermocouple recording (standard method) and mobile phone thermography.Results: All cold challenge summary measures, including AUC and MAX, increased after iloprost (most not significantly). However, when the response curves were modelled after averaging across fingers (linear mixed models, three versions), significant change was detected. For example, with Model 1 (no interaction between period and time), temperature was on average 1.67ºC [95% confidence interval (CI) 1.49-1.85, p < 0.001] higher post-iloprost. Mobile phone and thermocouple temperature measurements showed a strong estimated latent correlation (0.88, 95% CI 0.81-0.92). The estimated increases/hour were 0.25ºC (95% CI 0.05-0.45) for the thermocouple and 0.36ºC (95% CI 0.13-0.60) for mobile phone thermography.Conclusion: Our pilot study suggests that the thermographic response to a cold challenge is sensitive to change and mobile phone thermography could bring feasibility to thermographic parameters as outcome measures in later-phase, large-scale, community-based clinical trials of RP.

Biogeographic origins of southern African Silene (Caryophyllaceae)

Silene (Caryophyllaceae) is distributed predominantly in the northern Hemisphere, where it is most diverse around the Mediterranean Basin. The genus is also well represented in North Africa, extending into tropical, sub-Saharan and southern Africa. Eight native species are recognized in southern Africa, taxonomically placed in two sections: Elisanthe and Silene s.l. Although the taxonomy of the southern African taxa has recently been revised, their phylogenetic relationships and biogeographic history remain unclear. This study aims to infer the phylogenetic position and geographic origins of the southern African taxa. We generated DNA sequences of nuclear and plastid loci from several individuals belonging to all eight species of Silene recognized from southern Africa, and combined our DNA sequences with existing data representing species from major clades (i.e. sections) based on the recently revised Silene infrageneric taxonomy. We used a Bayesian coalescent species tree continuous diffusion approach to co-estimate the species tree and the ancestral areas of representative members of the genus. Our results show that the perennial southern African members of section Elisanthe form a strongly-supported clade with the Eurasian annual S. noctiflora and the Central Asian perennial S. turkestanica. The rest of the perennial species form a strongly-supported clade together with the annual S. aethiopica, which is nested in a larger Mediterranean clade comprising mostly annual species classified in section Silene s.l. Estimates of ancestral areas indicate a late Pleistocene dispersal to southern Africa from central and East Africa for the sub-Saharan members of section Silene s.l. The Elisanthe clade is inferred to have colonized southern Africa through long-distance dispersal from Eurasia during the late Pleistocene. Our findings support the hypothesis of a relatively recent colonization into southern Africa resulting from two independent dispersal events during the Pleistocene.

The impact of exercise on sleep in people with Parkinson's disease a scoping review

While high intensity exercise is associated with improvement of both motor and non-motor symptoms in Parkinson's disease (PD), there is limited evidence on its impact on sleep disturbances in PD. This scoping review aims to provide a preliminary statement of the potential size and scope of available evidence for the interaction between exercise and sleep in people with PD. Research to date on non-motor symptoms of PD is broad, with scarce information regarding specific effects of exercise on sleep. A systematic literature search was conducted through three phases. Fifteen articles met the inclusion criteria for this study. Resistive exercise and multimodal exercise programs were frequently studied and found to improve sleep and decrease sleep-related disorders. These findings suggest that exercise programs may improve sleep and other non-motor symptoms of PD. The research was inconclusive when comparing the effects of high and low intensity exercises. Further research on the interaction between exercise and sleep in PD may have implications for rehabilitative therapy interventions.

Imaging digital arteries in systemic sclerosis by tomographic 3-dimensional ultrasound

Objective methods are needed to quantify digital artery disease in systemic sclerosis (SSc) for clinical trials of vascular therapies. Our primary aim was to examine feasibility of a novel tomographic three-dimensional-(3-D) ultrasound (tUS) with high-frequency ultrasound (HFUS) or ultra-high-frequency ultrasound (UHFUS) to assess the digital arteries in patients with SSc compared to healthy controls. A secondary objective was to compare the total wall volume (TWV) as a measure of intimal/medial thickness. Eighteen patients with a confirmed diagnosis of SSc were studied by tUS HFUS (17.5 MHz, n = 10) or tUS UHFUS (48 and 70 MHz, n = 8) with equal numbers of healthy controls of similar age and gender. The majority of patients had limited cutaneous SSc and were representative of a spectrum of digital vasculopathy, with over half (n = 6 HFUS and n = 5 UHFUS) having previous digital ulceration. Over half were receiving oral vasodilatory therapy. TWV was measured in both digital arteries of the middle finger bilaterally. At least, two digital arteries could be identified at 17.5 MHz in all patients and healthy controls. Whereas, at least two digital arteries could be identified in relatively fewer patients compared to healthy controls using 48 MHz (n = 6 and 10) and especially 70 MHz (n = 4 and 10) UHFUS. The median difference in TWV between patients and healthy controls was -6.49 mm³ using 17.5 MHz, 1.9 mm³ at 48 MHz, and -0.4 mm³ at 70 MHz. tUS using UHFUS is a feasible method to measure TWV of digital arteries in SSc. Transducer frequency plays an important factor in successful digital artery measurement, with 48 MHz being the optimal frequency.

AB0622 ASSOCIATIONS WITH DIGITAL PITTING IN SYSTEMIC SCLEROSIS: A RETROSPECTIVE ANALYSIS

Background:

Digital pitting, the loss of tissue at the fingertip, is a cardinal feature of systemic sclerosis (SSc), contributing 3 of the 9 required points to fulfil the 2013 ACR/EULAR classification criteria. However, research into digital pitting has been scarce, despite it being painful and impacting on hand function.

Objectives:

To identify factors associated with digital pitting in patients with SSc.

Methods:

This was a retrospective analysis of data from patients with SSc attending a tertiary referral centre. Patients were subdivided into those with and without digital pitting, as recorded at their last documented attendance. The following variables were analysed: age, gender, age at Raynaud’s onset, age at SSc onset, limited/ diffuse cutaneous subtype, history of intravenous (IV) vasodilators, amputations, debridements and autoantibody status (anti-RNA polymerase, anti-Scl70, anti-centromere and anti-RNP).

Results:

Data were available from 713 patients with SSc. Digital pitting was present in approximately half of these patients (n=362, 51%). Table 1 summarises their characteristics.

Table 1.

Descriptive statistics of patients with and without digital pitting

Digital Pitting(n=362)No Digital Pitting(n=351)Age, mean (SD)67.1 (14.5)66.5 (13.6)Females, n (%)287 (79.3)301 (85.8)Age at Raynaud’s onset/ Age at SSc onset, median (IQR)39.3 (25.2, 49.3)/ 41.4 (26.2, 52.5)47.5 (35.3, 57.3)/ 52.5 (41.9, 60.4)Limited/ Diffuse subtype, n (%)276/85 (76.5/ 23.6)257/93 (73.6/ 26.6)History of IV vasodilators, n (%)167 (46.4)52 (14.9)History of amputations, n (%)52 (14.4)5 (1.4)Debridements, n (%)72 (20.2)18 (5.1)Autoantibody status, n (%):Anti-RNA polymerase/ Anti-Scl70/Anti-centromere/ Anti-RNP13 (6.2)1/ 61 (17.1)3/ 152 (42.6)5/ 15 (4.3)734 (14.0)2/ 41 (12.0)4/ 120 (35.4)6/ 22 (6.5)8

Denominator populations1210,2246,3357,4345,5357,6341,7352,8341

From the univariable analysis (Table 2), gender (female, p=0.02), age at Raynaud’s onset (p<0.001), age at SSc onset (p<0.001), IV vasodilators (p<0.001), amputations (p<0.001), debridements (p<0.001), anti-RNA polymerase (p=0.01), anti-Scl70 (p=0.05) and anti-centromere (p=0.05) were found to be significantly associated (anti-RNA polymerase negatively (p=0.20)) with digital pitting (p≤0.05). Further analysis adjusting the p value for multiple testing (Bonferroni adjustment, p≤0.0036) found age at Raynaud’s onset, age at SSc onset, history of IV vasodilators, amputations and debridements to be significantly associated with digital pitting.

Table 2.

Univariable logistic regression

Odds Ratio95% Confidence IntervalP value1Number of patients in each analysisAge1.0000.998 to 1.0030.62713Female1.1161.015 to 1.2310.02713Age at Raynaud’s onset1.0081.007 to 1.010<0.001713Age at SSc onset1.0041.003 to 1.005<0.001713Limited/ Diffuse subtype1.039/ 1.0411.049 to 1.127/ 1.046 to 1.1390.39/ 0.35710/ 711History of IV vasodilators1.4481.336 to 1.553<0.001710History of amputations1.5531.363 to 1.768<0.001713Debridements1.4051.259 to 1.568<0.001707Autoantibody status:Anti-RNA polymerase/ Anti-Scl70/ Anti-centromere/ Anti-RNP1.223/ 1.111/ 1.081/ 1.1141.052 to 1.419/ 1.000 to 1.234/ 1.002 to 1.162/ 1.310 to 1.7860.01/ 0.05/ 0.05/ 0.20456/ 702/ 698/ 693

1p≤0.05

Conclusion:

The results from this exploratory study in a large cohort of SSc patients provide valuable insights into factors associated with digital pitting. Patients with digital pitting often have an earlier onset of Raynauds and of SSc and significantly more debridements/amputations, suggesting that digital pitting is associated with vascular disease severity. Our findings indicate the need for further research investigating pathophysiology of digital pitting, to inform development of preventative treatment strategies.

Disclosure of Interests:

None declared

Impact and associates of digital pitting in patients with systemic sclerosis: a pilot study

Objective: Despite being a cardinal clinical sign of systemic sclerosis (SSc), digital pitting has been little studied. Our objective was to test, in a pilot study, the hypothesis that pitting is painful and associated with digital vascular disease severity.Method: Fifty patients with SSc were recruited: 25 with and 25 without digital pitting. Fingertip pain was assessed on a 0-10 scale. Thermography of both hands assessed surface temperature, allowing calculation of the distal-dorsal difference (temperature gradient) for each finger. Nailfold capillaroscopy was performed in each finger using a dermatoscope, and graded on a 0-3 scale (0 = normal; 3 = grossly abnormal).Results: In the 25 patients with digital pitting, 65 fingers in total were affected (mainly the index and middle fingers). Pain scores were higher in 'pitting' patients [median 4 (interquartile range 3-8) vs 0 (0-2), p < 0.001], and pitting patients reported that pitting impacted on activities of everyday living. Temperature gradients along the fingers did not differ significantly between patients with and without pitting (p = 0.248). Pitting patients were more likely to have 'grossly abnormal' capillaries than those without pitting, and less likely to have 'no/mild' nailfold capillary changes.Conclusions: Digital pitting is painful and impacts on hand function. Capillaroscopy findings provide further support for an association between pitting and severity of digital vascular change. Larger, more comprehensive studies are required to examine the pathophysiology of pitting and to pave the way to therapeutic intervention, ideally including preventive strategies.

Digit ratio (2D:4D) and testosterone supplementation

BACKGROUND

Testosterone (T) is taken or prescribed to enhance appearance, increase athletic performance and libido and to treat hypogonadism. Digit ratio (2D:4D) is thought to be a negative correlate of prenatal T. Here we consider the relationship between 2D:4D and T supplementation.

AIMS

Our sample was taken from the BBC internet study. Respondents were asked (y/n) if they were taking; (i) T, (ii) hormone replacement therapy with T (HRTwT). We removed extreme 2D:4D values and age and considered the most numerous ethnic group (i.e. "Whites"). Analyses were performed with a two-factor (sex*T) analysis of variance with covariate age and dependent variables 2D:4D or right-left 2D:4D (Dr-l).

RESULTS

Out of 197,589 respondents, 793 (598 males) reported taking T. There was a significant main effect for right 2D:4D such that T supplementing males had higher 2D:4D than those who did not. The sex*T interaction was significant, but the effect reversed in females. There were 22,576 (661 males) participants who reported taking HRTwT. We found a significant main effect for right 2D:4D, males taking HRTwT had higher 2D:4D than those who did not. This was reversed in females. The sex*HRTwT interaction was significant, a high Dr-l was also found in males reporting HRTwT.

CONCLUSION

Males who reported taking T or HRTwT had high right 2D:4D and/or Dr-l. The situation with females may be the reverse of that found in males but effect sizes are less. The health implications of an association between high (feminized) 2D:4D and T supplementation in males are discussed.

OS9.5 Evidence that adult glioblastoma adapts to standard therapy though chromatin remodeling

BACKGROUND

Glioblastoma (GBM) tumours recur following standard treatment in almost all cases. We use ‘omics technologies to simultaneously profile pairs of primary and matched recurrent GBM to specifically identify and characterise the cells that resisted treatment, with the aim of determining how to more effectively kill them.

MATERIAL AND METHODS

We have analysed high coverage RNAseq data from pairs of GBM tumours: primary de novo tumour and matched local recurrence from patients that underwent standard therapy. Our original cohort constituted 23 pairs and our validation cohort was an additional 22 pairs. We also cultured two plates of spheroids directly from a patient’s GBM, treating one with radiation and temozolomide. We monitored growth and captured and sequenced RNA from single cells at two time-points: one week post-treatment when the deviation between untreated and treated spheroid growth curves was most pronounced; and three weeks post-treatment when the growth rate of treated spheroids had recovered. We investigated differential gene expression between primary and recurrent pairs, and single cells pre- and post-treatment, and performed a bespoke per patient gene set enrichment analysis.

RESULTS

Differential gene expression analysis in 23 tumour pairs indicated a treatment-induced shift in cell states linked to normal neurogenesis and prompted us to develop a novel gene set enrichment analysis approach to identify gene regulatory factors that may orchestrate such a shift. This revealed the significant and universal dysregulation of genes, through therapy, that are targeted by a specific chromatin remodeling machinery. This finding was validated in an independent cohort of 22 further GBM pairs. To understand the therapeutic potential of this finding we must determine whether genes are dysregulated through therapy owing to a) their fixed expression in inherently treatment resistance cells in the primary tumour which get selected during therapy to increase the signal of that profile, or b) changes in expression during the process of cells acquiring treatment resistance. To inspect this, we analysed single cell gene expression data from GBM spheroids pre- and post-treatment. We found that there was significant dysregulation of the genes associated with the chromatin remodeling complex but only at the three-week post-treatment time-point.

CONCLUSION

Our results indicate that GBM cells are being transcriptionally reprogrammed in response to treatment; the mechanism of which may represent a therapeutic opportunity.

Influence of psoas muscle area on mortality following elective abdominal aortic aneurysm repair

BACKGROUND

The effect of sarcopenia based on the total psoas muscle area (TPMA) on CT is inconclusive in patients undergoing abdominal aortic aneurysm (AAA) intervention. The aim of this prospective cohort study was to evaluate morphometric sarcopenia as a method of risk stratification in patients undergoing elective AAA intervention.

METHODS

TPMA was measured on preintervention CT images of patients undergoing elective endovascular aneurysm repair (EVAR) or open aneurysm repair. Mortality was assessed in relation to preintervention TPMA using Cox regression analysis, with calculation of hazard ratios at 30 days, 1 year and 4 years. Postintervention morbidity was evaluated in terms of postintervention care, duration of hospital stay and 30-day readmission. Changes in TPMA on surveillance EVAR imaging were also evaluated.

RESULTS

In total, 382 patient images acquired between March 2008 and December 2016 were analysed. There were no significant intraobserver and interobserver differences in measurements of TPMA. Preintervention TPMA failed to predict morbidity and mortality at all time points. The mean(s.d.) interval between preintervention and surveillance imaging was 361·3(111·2) days. A significant reduction in TPMA was observed in men on surveillance imaging after EVAR (mean reduction 0·63(1·43) cm2 per m2 ; P < 0·001). However, this was not associated with mortality (adjusted hazard ratio 1·00, 95 per cent c.i. 0·99 to 1·01; P = 0·935).

CONCLUSION

TPMA is not a suitable risk stratification tool for patients undergoing effective intervention for AAA.

Voluntary control of breathing affects center of pressure complexity during static standing in healthy older adults

Background Physiological/biomechanical systems display high degrees of complexity in their corresponding physiological and/or biomechanical outputs, indicative of normal healthy physiological functioning, though little attention has been paid to potential mechanisms which may affect complexity. Center of pressure (CoP) dynamics also display high degrees of complexity and may be affected via altered respiratory-motor interactions such as during voluntary control of breathing. Purpose The purpose of this study was to investigate the differences in the complexity of CoP dynamics during autonomous vs. voluntary control of breathing and between different voluntarily controlled breathing conditions. Methods Center of pressure recordings were taken from 18 older adults during static standing under three different breathing conditions: 1) neutral breathing, 2) abdominal breathing, and 3) thoracic breathing, the first constituting the autonomous breathing condition and the latter two constituting voluntarily controlled breathing conditions. CoP dynamics were quantified using sample entropy, standard deviation, 95% sway area, and average radial velocity. Repeated measure MANOVAs were used to assess the effect of breathing on CoP dynamics, with top-down application of ANOVAs and pairwise comparison as needed. Results Voluntary control of breathing during both conditions resulted in significantly higher CoP variability and lower sample entropy than during autonomous control of breathing in the mediolateral direction, indicating less complex dynamics and loss of system control. No significant differences between voluntary breathing conditions were observed. Conclusion Voluntary control of breathing significantly affected on CoP dynamics during static standing. The complexity of the postural control system may be affected via alterations in respiratory-motor interactions.

Changes in disability and their relationship with skin thickening, in diffuse and limited cutaneous systemic sclerosis: a retrospective cohort study

OBJECTIVE

The burden of disability associated with systemic sclerosis (SSc) is being increasingly recognized. Our aim was to test the hypothesis that changes in functional ability over time differ between patients with limited (lcSSc) and diffuse cutaneous (dcSSc) subtypes, and that in dcSSc (but not lcSSc) these changes correlate with skin thickening.

METHOD

This was a retrospective analysis of data collected prospectively between 2005 and 2016 at a single centre. Data recorded at annual review visits included modified Rodnan skin score (mRSS) and Health Assessment Questionnaire Disability Index (HAQ-DI). Yearly rates of mRSS and HAQ-DI change were assessed by individual linear regressions, and those gradients were compared between disease groups (lcSSc/dcSSc) for each of early/late disease (less/greater than 5 years' duration).

RESULTS

The study included 402 patients (110 dcSSc, 292 lcSSc), with mean length of follow-up of 5.5 years (sd 3.5). Mean baseline HAQ-DI was 1.4 in dcSSc and 1.2 in lcSSc. In dcSSc, increased mRSS was associated with worsening disability (ρ = 0.36, p = 0.004) during early but not late disease (ρ = 0.12, p = 0.331). In lcSSc, changes in mRSS were not associated with changes in disability for early (ρ = -0.15, p = 0.173) or late disease (ρ = 0.10, p = 0.137).

CONCLUSION

These findings confirm high disability in patients with SSc. A relationship between HAQ-DI and mRSS (worsening mRSS associated with increasing disability) was found only in patients with early dcSSc, suggesting that in other patient subgroups other factors play the major role.

A feasibility study of a novel low-level light therapy for digital ulcers in systemic sclerosis

Background: Locally acting, well-tolerated treatments for systemic sclerosis (SSc) digital ulcers (DUs) are needed.

Objectives: Our primary aim was to investigate the safety, feasibility, and tolerability of a novel low-level light therapy (LTTT). A secondary aim was to tentatively assess efficacy.

Methods: A custom-built device comprising infrared (850 nm), red (660 nm), and violet (405 nm) LEDs was utilized. DUs were irradiated with 10 J/cm² twice weekly for 3 weeks, with follow-up at weeks 4 and 8. Any safety concerns were documented. Patient opinion on time to deliver, feasibility, and pain visual analogue score (VAS; 0–100, 100 most severe) was collected. Patient and clinician DU global assessment VAS were documented. DUs were evaluated by laser Doppler perfusion imaging pre- and post-irradiation.

Results: In all, 14 DUs in eight patients received a total of 46 light exposures, with no safety concerns. All patients considered LTTT ‘took just the right amount of time’ and was ‘feasible’, with a low associated mean pain VAS of 1.6 (SD: 5.2). Patient and clinician global DC VAS improved during the study (mean change: –7.1 and –5.2, respectively, both p < .001). DU perfusion significantly increased post-irradiation.

Conclusions: LTTT for DUs is safe, feasible, and well tolerated. There was an early tentative suggestion of treatment efficacy.

Shoulder MRI Abnormalities in Asymptomatic Little League Baseball Players

Background:

Youth baseball is extremely popular in the United States, but it has been associated with shoulder pain and injury. The incidence of shoulder abnormalities in this athletic population has yet to be defined.

Purpose:

To examine abnormalities noted on magnetic resonance imaging (MRI) in the shoulders of asymptomatic Little League baseball players and to correlate these findings with the players’ throwing history and physical examinations.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

A total of 23 Little League baseball players aged 10 to 12 years were recruited. All players underwent a comprehensive physical examination and responded to a questionnaire addressing their playing history and any arm or shoulder pain. Bilateral shoulder MRIs were performed and read in a blinded manner by 2 radiologists. Responses on the questionnaire and physical examination findings were compared between participants with and without positive MRI findings through use of chi-square test and analysis of variance.

Results:

The dominant arm was 8.5 times more likely to have an abnormality on MRI compared with the nondominant arm. In all, 12 players (52%) had 17 positive MRI findings in their throwing shoulder that were not present in their nondominant shoulder. These findings included edema or widening of the proximal humeral physis (n = 5), labral tear (n = 4), partial rotator thickness tear (n = 4), acromioclavicular joint abnormality (n = 2), subacromial bursitis (n = 1), and cystic change of the greater tuberosity (n = 1). Two primary risk factors were associated with an abnormal MRI: year-round play and single-sport athletes focusing solely on baseball (P < .05). Players with no risk factors, 1 risk factor, and both risk factors had a 25%, 71%, and 100% chance, respectively, of having an abnormal MRI. A majority of players (61%) had previously experienced shoulder pain, especially pitchers throwing curveballs and sliders (P < .05), but this was not associated with an abnormal MRI.

Conclusion:

Abnormalities seen on MRI involving the shoulder are common in Little League baseball players, especially those who are single-sport athletes playing year-round.

Bone Marrow-Derived Cell Accumulation in the Spinal Cord Is Independent of Peripheral Mobilization in a Mouse Model of Amyotrophic Lateral Sclerosis

Bone marrow-derived cells (BMDCs) are capable of migrating across the blood–brain barrier (BBB) and accumulating in the central nervous system (CNS) when transplanted into recipients conditioned with whole-body irradiation or chemotherapy. We used the chemotherapeutic agents busulfan and treosulfan to condition recipient mice for transplantation with bone marrow (BM) cells isolated from donor mice ubiquitously expressing green fluorescent protein. We attempted to increase the accumulation of BMDCs in the CNS by mobilization of BMDCs using either, or both, granulocyte colony-stimulating factor (GCSF) or plerixafor (AMD3100). We also used several concentrations of busulfan. We hypothesized that higher concentrations of busulfan and BMDC mobilization would increase numbers of GFP⁺ cells in the CNS. The doses of busulfan employed (60–125 mg/kg) all resulted in high levels of sustained chimerism (>85% 1 year post-transplant) in both the blood and BM of wild-type (WT) mice and an amyotrophic lateral sclerosis (ALS) mouse model. Moreover, cells accumulated within the CNS in a dose-, time-, and disease-dependent manner. Conditioning with the hydrophilic busulfan analog treosulfan, which is unable to cross the BBB efficiently, also resulted in a high degree of BM chimerism. However, few GFP⁺ BMDCs were found within the CNS of WT or ALS mice of treosulfan-conditioned mice. Mobilization of BMDCs into the circulation using GCSF and/or AMD3100 did not lead to increased accumulation of GFP⁺ BMDCs within the CNS of WT or ALS mice. Weekly analysis of BMDC accumulation revealed that BMDCs accumulated more rapidly and to a greater extent in the CNS of ALS mice conditioned with a high dose (125 mg/kg) of busulfan compared to a lower dose (80 mg/kg). The number of GFP⁺ BMDCs in the CNS labeling with the proliferation marker Ki67 increased in parallel with BMDC accumulation within the CNS. Our results indicate that establishment of high levels of blood and BM chimerism alone is not sufficient to induce BMDC accumulation within the CNS and that CNS conditioning is a crucial requirement for BMDC accumulation to occur. Moreover, it appears that proliferation of BMDCs that infiltrate the CNS is partly responsible for cell accumulation in busulfan-conditioned ALS mice.

Counting complete? Finalising the plant inventory of a global biodiversity hotspot

The Cape Floristic Region-the world's smallest and third richest botanical hotspot-has benefited from sustained levels of taxonomic effort and exploration for almost three centuries, but how close is this to resulting in a near-complete plant species inventory? We analyse a core component of this flora over a 250-year period for trends in taxonomic effort and species discovery linked to ecological and conservation attributes. We show that >40% of the current total of species was described within the first 100 years of exploration, followed by a continued steady rate of description. We propose that <1% of the flora is still to be described. We document a relatively constant cohort of taxonomists, working over 250 years at what we interpret to be their 'taxonomic maximum.' Rates of description of new species were independent of plant growth-form but narrow-range taxa have constituted a significantly greater proportion of species discoveries since 1950. This suggests that the fraction of undiscovered species predominantly comprises localised endemics that are thus of high conservation concern. Our analysis provides important real-world insights for other hotspots in the context of global strategic plans for biodiversity in informing considerations of the likely effort required in attaining set targets of comprehensive plant inventories. In a time of unprecedented biodiversity loss, we argue for a focused research agenda across disciplines to increase the rate of species descriptions in global biodiversity hotspots.

Reduced perfusion in systemic sclerosis digital ulcers (both fingertip and extensor) can be increased by topical application of glyceryl trinitrate

Objectives

In patients with systemic sclerosis (SSc), fingertip digital ulcers (DUs) are believed to be ischaemic, and extensor surface DUs a result of mechanical factors/microtrauma. Our aim was to assess blood flow response to topical glyceryl trinitrate (GTN) compared to placebo in SSc DUs, looking for differences in pathophysiology between fingertip and extensor lesions.

Method

This was a double-blind, randomised, crossover, placebo-controlled study. Sixteen (6 fingertip, 10 extensor) DUs were each studied twice (one day apart): once with GTN and once with placebo ointment. Perfusion at the DU centre (‘DUCore’) and periphery (‘DUPeriphery’), as measured by laser Doppler imaging was performed before and immediately after ointment application, then every 10 min, up to 90 min post-application. We calculated the area under the response curve (AUC) and the ratio of peak perfusion to baseline, then compared these between GTN and placebo.

Results

Perfusion was lower in the DUCore compared to the DUPeriphery (ratio of 0.52). The microvessels of the DUCore were responsive to GTN, with an increase in perfusion, with a similar effect in both fingertip and extensor DUs. The AUC and peak/baseline perfusion difference in means (ratio, 95% confidence interval) between GTN and placebo at the DUCore were 1.2 (1.0–1.6) and 1.2 (1.0–1.5) respectively, and at the DUPeriphery were 1.1 (0.8–1.6) and 1.0 (0.9–1.2) respectively.

Conclusion

DUs (both fingertip and extensor) were responsive to topical GTN, with an increase in perfusion to the ischaemic DU centre. If both fingertip and extensor DUs have a (potentially reversible) ischaemic aetiology, this has important treatment implications.

•

SSc fingertip DUs are believed to be ischaemic, whereas, extensor surface DUs are a result of mechanical factors/microtrauma.

•

DUs (both fingertip and extensor) were responsive to topical GTN, in particular the ischaemic centre.

•

If both fingertip and extensor DUs have a ischaemic aetiology, this has important treatment implications.

In vivo neutralization of IL-6 receptors ameliorates gastrointestinal dysfunction in dystrophin-deficient mdx mice

BACKGROUND

Duchenne muscular dystrophy (DMD) is a fatal disease characterized by progressive deterioration and degeneration of striated muscle. A mutation resulting in the loss of dystrophin, a structural protein which protects cells from contraction-induced damage, underlies DMD pathophysiology. Damage to muscle fibers results in chronic inflammation and elevated levels of proinflammatory cytokines such as interleukin-6 (IL-6). However, loss of cellular dystrophin also affects neurons and smooth muscle in the gastrointestinal (GI) tract with complaints such as hypomotility, pseudo-obstruction, and constipation reported in DMD patients.

METHODS

Using dystrophin-deficient mdx mice, studies were carried out to examine colonic morphology and function compared with wild-type mice. Treatment with neutralizing IL-6 receptor antibodies (xIL-6R) and/or the corticotropin-releasing factor (CRF) 2 receptor agonist, urocortin 2 (uro2) was tested to determine if they ameliorated GI dysfunction in mdx mice.

KEY RESULTS

Mdx mice exhibited thickening of colonic smooth muscle layers and delayed stress-induced defecation. In organ bath studies, neurally mediated IL-6-evoked contractions were larger in mdx colons. In vivo treatment of mdx mice with xIL-6R normalized defecation rates and colon lengths. Uro2 treatment did not affect motility or morphology. The potentiated colonic contractile response to IL-6 was attenuated by treatment with xIL-6R.

CONCLUSIONS & INFERENCES

These findings confirm the importance of dystrophin in normal GI function and implicate IL-6 as an important regulator of GI motility in the mdx mouse. Inhibition of IL-6 signaling may offer a potential new therapeutic strategy for treating DMD-associated GI symptoms.

Calcinosis preferentially affects the thumb compared to other fingers in patients with systemic sclerosis

OBJECTIVES

Although Raynaud's phenomenon often spares the thumb, clinical experience suggests conversely that, in patients with systemic sclerosis (SSc), the thumb is frequently affected by calcinosis (as is demonstrated on plain radiographs). Our aim was to investigate the hypothesis that, in patients with SSc, thumbs are more commonly affected by calcinosis than other digits.

METHOD

Sixty-eight hand radiographs with at least one area of calcinosis were identified. Each digit on both hands of each patient was assigned a severity score on a scale from 0 to 3 (0 = no calcinosis, 3 = most severe). The scoring was completed twice, including and excluding the metacarpals.

RESULTS

Right hands were found to be associated with slightly higher scores than left hands [estimate 0.14, 95% confidence interval (CI) 0.03-0.26]. Scores were lower for other fingers compared to thumbs. There was strong evidence (p < 0.0001) of a trend of decreasing severity moving from the thumb to the little finger. There was no evidence that the pattern of severity across the fingers was different on left and right hands (p = 0.77). The results were similar whether or not metacarpals were included.

CONCLUSIONS

The thumb is affected by calcinosis more than other digits, followed by the index finger. This observation provides insight into the pathogenesis of SSc-related calcinosis, which may relate more to repetitive trauma than to ischaemia.

Stay or stray? Evidence for alternative mating strategy phenotypes in both men and women

In all comparative analyses, humans always fall on the borderline between obligate monogamy and polygamy. Here, we use behavioural indices (sociosexuality) and anatomical indices (prenatal testosterone exposure indexed by 2D : 4D digit ratio) from three human populations to show that this may be because there are two distinct phenotypes in both sexes. While males are more promiscuous and display higher prenatal testosterone exposure than females overall, our analyses also suggest that the within-sex variation of these variables is best described by two underlying mixture models, suggesting the presence of two phenotypes with a monogamous/promiscuous ratio that slightly favours monogamy in females and promiscuity in males. The presence of two phenotypes implies that mating strategy might be under complex frequency-dependent selection.

Local adaptation: Mechanical fit between floral ecotypes of Nerine humilis (Amaryllidaceae) and pollinator communities

Geographic variation in floral morphology is often assumed to reflect geographic variation in pollinator communities and associated divergence in selective pressures. We studied populations of Nerine humilis (Amaryllidaceae) to assess whether geographic variation in floral form is the result of local adaptation to different pollinator communities. We first tested for associations between floral traits and visitor communities, and found that populations with similar floral morphologies were visited by similar insect communities. Mean style length in each population was also closely associated with the mean body length of the local visitor community. A reciprocal translocation experiment demonstrated that native phenotypes set more seed than translocated phenotypes. Single visitation experiments showed that native flowers received more pollen, and set more seed per visit, than introduced phenotypes in both populations. This suggests that the effectiveness of pollinator visits is determined by the degree of mechanical fit between flowers and visitors. We provide strong evidence that the observed among-population variation in floral traits is an adaptive response to geographic variation in the pollinator community.

Digit ratio (2D:4D) and salivary testosterone, oestradiol and cortisol levels under challenge: Evidence for prenatal effects on adult endocrine responses

BACKGROUND

Digit ratio (2D:4D) is a marker for prenatal sex steroids and a correlate of sporting performance. This association may exist because low 2D:4D is linked to high prenatal levels of testosterone (T) and low oestrogens (E). It was recently suggested that low 2D:4D, and particularly low right-left 2D:4D (or Dr-l), is a marker for T changes in response to physical and aggressive challenges. If correct, this link may in part explain the association between 2D:4D and sports performance.

AIMS

We tested this hypothesis in adults.

STUDY DESIGN

Three experimental treatments were completed using a randomised, cross-over design; (i) cycle sprints plus an aggressive video (S+V), (ii) aggressive video plus cycle sprints (V+S), and (iii) a control session.

SUBJECTS

24 healthy adults (12 men and 12 women).

OUTCOME MEASURES

Salivary T, oestradiol (E2) and cortisol (C) levels were measured on six occasions across each session and pooled for analysis.

RESULTS

The S+V treatment was associated with a rise in T and C levels, and Dr-l was significantly and negatively correlated with T and E2 with these effects confined to men. The right 2D:4D and Dr-l were also negatively correlated with the T/C ratio and Dr-l negatively related to the E2/C ratio in men during the S+V treatment.

CONCLUSIONS

We suggest that the hormonal responses to a challenge are programmed by prenatal levels of T and E with possible links to sporting performance in adulthood.

Busulfan as a myelosuppressive agent for generating stable high-level bone marrow chimerism in mice

Bone marrow transplantation (BMT) is often used to replace the bone marrow (BM) compartment of recipient mice with BM cells expressing a distinct biomarker isolated from donor mice. This technique allows for identification of donor-derived hematopoietic cells within the recipient mice, and can be used to isolate and characterize donor cells using various biochemical techniques. BMT typically relies on myeloablative conditioning with total body irradiation to generate niche space within the BM compartment of recipient mice for donor cell engraftment. The protocol we describe here uses myelosuppressive conditioning with the chemotherapeutic agent busulfan. Unlike irradiation, which requires the use of specialized facilities, busulfan conditioning is performed using intraperitoneal injections of 20 mg/kg busulfan until a total dose of 60-100 mg/kg has been administered. Moreover, myeloablative irradiation can have toxic side effects and requires successful engraftment of donor cells for survival of recipient mice. In contrast, busulfan conditioning using these doses is generally well tolerated and mice survive without donor cell support. Donor BM cells are isolated from the femurs and tibiae of mice ubiquitously expressing green fluorescent protein (GFP), and injected into the lateral tail vein of conditioned recipient mice. BM chimerism is estimated by quantifying the number of GFP+ cells within the peripheral blood following BMT. Levels of chimerism >80% are typically observed in the peripheral blood 3-4 weeks post-transplant and remain established for at least 1 year. As with irradiation, conditioning with busulfan and BMT allows for the accumulation of donor BM-derived cells within the central nervous system (CNS), particularly in mouse models of neurodegeneration. This busulfan-mediated CNS accumulation may be more physiological than total body irradiation, as the busulfan treatment is less toxic and CNS inflammation appears to be less extensive. We hypothesize that these cells can be genetically engineered to deliver therapeutics to the CNS.

Matching floral and pollinator traits through guild convergence and pollinator ecotype formation

BACKGROUND AND AIMS

Pollinator landscapes, as determined by pollinator morphology/behaviour, can vary inter- or intraspecifically, imposing divergent selective pressures and leading to geographically divergent floral ecotypes. Assemblages of plants pollinated by the same pollinator (pollinator guilds) should exhibit convergence of floral traits because they are exposed to similar selective pressures. Both convergence and the formation of pollination ecotypes should lead to matching of traits among plants and their pollinators.

METHODS

We examined 17 floral guild members pollinated in all or part of their range by Prosoeca longipennis, a long-proboscid fly with geographic variation in tongue length. Attractive floral traits such as colour, and nectar properties were recorded in populations across the range of each species. The length of floral reproductive parts, a mechanical fit trait, was recorded in each population to assess possible correlation with the mouthparts of the local pollinator. A multiple regression analysis was used to determine whether pollinators or abiotic factors provided the best explanation for variation in floral traits, and pollinator shifts were recorded in extralimital guild member populations.

KEY RESULTS

Nine of the 17 species were visited by alternative pollinator species in other parts of their ranges, and these displayed differences in mechanical fit and attractive traits, suggesting putative pollination ecotypes. Plants pollinated by P. longipennis were similar in colour throughout the pollinator range. Tube length of floral guild members co-varied with the proboscis length of P. longipennis.

CONCLUSIONS

Pollinator shifts have resulted in geographically divergent pollinator ecotypes across the ranges of several guild members. However, within sites, unrelated plants pollinated by P. longipennis are similar in the length of their floral parts, most probably as a result of convergent evolution in response to pollinator morphology. Both of these lines of evidence suggest that pollinators play an important role in selecting for certain floral traits.

Digit Ratio (2D:4D): A Biomarker for Prenatal Sex Steroids and Adult Sex Steroids in Challenge Situations

Digit ratio (2D:4D) denotes the relative length of the second and fourth digits. This ratio is considered to be a biomarker of the balance between fetal testosterone (T) and estrogen (E) in a narrow window of early ontogeny. Evidence for this assertion is derived from direct and indirect measures of prenatal hormonal exposure (in experimental animals, via amniotic fluid samples and in the study of sex-typical traits) in relation to 2D:4D. In contrast, the relationships between 2D:4D and levels of sex steroids in adults are less clear, as many correlational studies of 2D:4D and adult sex steroids have concluded that this association is statistically non-significant. Here, we suggest that in order to understand the link between 2D:4D and sex hormones, one must consider both fetal organizing and adult activating effects of T and E. In particular, we hypothesize that 2D:4D correlates with organizing effects on the endocrine system that moderate activating effects in adulthood. We argue that this is particularly evident in "challenging" conditions such as aggressive and sexual encounters, in which individuals show increased levels of T. We discuss this refinement of the 2D:4D paradigm in relation to the links between 2D:4D and sports performance, and aggression.