Declining levels of serum chemokine (C-X-C motif) ligand 10 over time are associated with new onset of psoriatic arthritis in patients with psoriasis: a new biomarker?

BACKGROUND: We previously found that serum levels of chemokine (C-X-C motif) ligand 10 (CXCL10) decreased after the onset of psoriatic arthritis (PsA). OBJECTIVES: We measured CXCL10 levels over time in patients with psoriasis who developed PsA to determine whether the drop in CXCL10 was specific to these patients and further assess its association with PsA development. METHODS: Prospectively followed patients with psoriasis without arthritis [cutaneous psoriasis (PsC)] were assessed yearly by rheumatologists for the presence of PsA. Patients with PsC who developed PsA (converters) were matched to those that did not develop PsA (nonconverters) based on psoriasis duration and the interval between follow-up visits. The duration between baseline and the first visit postconversion in converters was used to assign a pseudoconversion date in nonconverters. Linear mixed-effects models were used to model the expression of CXCL10 over time. RESULTS: CXCL10 significantly declined over time in converters prior to PsA development with a significant difference in the trend over time between converters (n = 29) and nonconverters (n = 52; P < 0·001). CXCL10 continued to decline after PsA onset in a subset of converters. There was a significant difference in the trend of CXCL10 levels between converters (n = 24) and nonconverters (n = 16; P = 0·01) preconversion/pseudoconversion. This difference remained postconversion (P = 0·006) and was not different from the preconversion period (P = 0·75). CONCLUSIONS: A large difference in CXCL10 was identified in patients with PsC that are destined to develop PsA over time. This exploratory analysis supports the association of CXCL10 with PsA development in patients with PsC and warrants further study of the predictive ability of this chemokine. What is already known about this topic? Chemokine (C-X-C motif) ligand 10 (CXCL10) is elevated in psoriatic affected tissues and serum and/or plasma. Patients with psoriasis that develop psoriatic arthritis (PsA) have elevated CXCL10 levels at baseline and these levels drop after arthritis onset. What does this study add? By monitoring levels of CXCL10 in serum over multiple visits in patients with psoriasis that develop PsA as well as those that do not develop PsA, an association was identified between CXCL10 and PsA development. What is the translational message? CXCL10 is a strong candidate for use by physicians for the detection of patients with psoriasis that are at risk of developing PsA. Linked Comment: Kirby and Fitzgerald. Br J Dermatol 2020; 183:805-806.

Validation of an Oral Disease Severity Score (ODSS) tool for use in oral mucous membrane pemphigoid.

BACKGROUND: Mucous membrane pemphigoid (MMP) is a rare autoimmune bullous disease predominantly affecting the oral mucosa. Optimal management relies upon thorough clinical assessment and documentation at each visit. OBJECTIVES: The primary aim of this study was to validate the Oral Disease Severity Score (ODSS) for the assessment of oral involvement in MMP. We also compared its inter- and intraobserver reliability with those of the oral parts of the Mucous Membrane Pemphigoid Disease Area Index (MMPDAI), Autoimmune Bullous Skin Disorder Intensity Score (ABSIS) and Physician's Global Assessment (PGA). METHODS: Fifteen patients with mild-to-moderately severe oral MMP were scored for disease severity by 10 oral medicine clinicians from four U.K. centres using the ODSS, the oral sections of MMPDAI and ABSIS, and PGA. Two clinicians rescored all patients after 2 h. RESULTS: In terms of reliability, the interobserver ODSS total score intraclass correlation coefficient (ICC) was 0·97, MMPDAI activity 0·59 and damage 0·15, ABSIS total 0·84, and PGA 0·72. The intraobserver ICCs (two observers) for ODSS total were 0·97 and 0·93; for MMPDAI activity 0·93 and 0·70 and damage 0·93 and 0·79; for ABSIS total 0·99 and 0·94; and for PGA 0·92 and 0·94. Convergent validity between ODSS and MMPDAI was good (correlation coefficient 0·88). The mean ± SD time for completion of ODSS was 93 ± 31 s, with MMPDAI 102 ± 24 s and ABSIS involvement 71 ± 18 s. The PGA took < 5 s. CONCLUSIONS: This study has validated the ODSS for the assessment of oral MMP. It has shown superior interobserver agreement over MMPDAI, ABSIS and PGA, and superior intraobserver reliability to MMPDAI. It is quick and easy to perform. What's already known about this topic? There are no validated scoring methodologies for oral mucous membrane pemphigoid (MMP). Proposed disease activity scoring tools for MMP include the Mucous Membrane Disease Area Index (MMPDAI) and the Autoimmune Bullous Skin Disorder Intensity Score (ABSIS). The Oral Disease Severity Score (ODSS) has been validated for use in oral pemphigus vulgaris (PV). It has been shown to be reliable and sensitive in both lichen planus (LP) and MMP. What does this study add? The ODSS has been shown to be a thorough, sensitive and reproducible, yet quick scoring tool for the assessment of oral involvement in MMP. Its versatility for use in oral PV, MMP and LP is an added advantage over other scoring methodologies. What are the clinical implications of this work? We propose that the ODSS be used as a clinical scoring tool for monitoring activity in oral MMP in clinical practice as well as for use in multicentre studies.

Goftte: A R package for assessing goodness-of-fit in proportional (sub) distributions hazards regression models.

BACKGROUND AND OBJECTIVE: In this paper, we introduce a new R package goftte for goodness-of-fit assessment based on cumulative sums of model residuals useful for checking key assumptions in the Cox regression and Fine and Gray regression models. METHODS: Monte-Carlo methods are used to approximate the null distribution of cumulative sums of model residuals. To limit the computational burden, the main routines used to approximate the null distributions are implemented in a parallel C++ programming environment. Numerical studies are carried out to evaluate the empirical type I error rates of the different testing procedures. The package and the documentation are available to users from CRAN R repositories. RESULTS: Results from simulation studies suggested that all statistical tests implemented in goftte yielded excellent control of the type I error rate even with modest sample sizes with high censoring rates. CONCLUSIONS: As compared to other R packages goftte provides new useful method for testing functionals, such as Anderson-Darling type test statistics for checking assumptions about proportional (sub-) distribution hazards. Approximations for the null distributions of test statistics have been validated through simulation experiments. Future releases will provide similar tools for checking model assumptions in multiplicative intensity models for recurrent data. The package may help to spread the use of recent advocated goodness-of-fit techniques in semiparametric regression for time-to-event data.

Human Disease/Clinical Medical Sciences in Dentistry: Current state and future directions of undergraduate teaching in the UK and Ireland.

In March 2017, a group of teachers of human disease/clinical medical science (HD/CMSD) representing the majority of schools from around the UK and Republic of Ireland met to discuss the current state of teaching of human disease and also to discuss how the delivery of this theme might evolve to inform improved healthcare. This study outlines how the original teaching in medicine and surgery to dental undergraduate students has developed into the theme of HD/CMSD reflecting changing needs as well as guidance from the regulators, and how different dental schools have developed their approaches to reach their current state. Each school was also asked to share a strengths, weakness, opportunities and threats (SWOT) analysis of their programme and to outline how they thought their HD/CMSD programme may develop. The school representatives who coordinate the delivery and assessment of HD/CMSD in the undergraduate curriculum have extensive insight in this area and are well-placed to shape the HD/CMSD development for the future.

An Oral Disease Severity Score validated for use in oral pemphigus vulgaris.

BACKGROUND: Pemphigus vulgaris (PV) is a rare autoimmune bullous disease, which can present with recalcitrant oral mucosal lesions. Optimal management of PV relies upon careful clinical assessment and documentation. OBJECTIVES: The primary aim of this study was to validate the Oral Disease Severity Score (ODSS) for the assessment of oral involvement in PV. A secondary aim was to compare its inter- and intraobserver variability and ease of use with the Physician's Global Assessment (PGA) and the oral scoring methods used in the Autoimmune Bullous Skin Disorder Intensity Score (ABSIS) and the Pemphigus Disease Area Index (PDAI). METHODS: Fifteen patients with mild-to-moderately severe oral PV were scored for disease severity by 10 oral medicine clinicians using the ODSS, the PGA and the oral sections of ABSIS and PDAI. Two clinicians rescored all patients after a minimum 2-h interval. RESULTS: Interobserver reliability was assessed using an intraclass correlation coefficient (ICC). For the ODSS total score the ICC was 0·83, for PDAI (oral total activity) 0·79, ABSIS (oral total) 0·71 and PGA 0·7. Intraobserver agreement between initial scoring and rescoring of the same patient by two clinicians demonstrated an ICC for each of 0·97 and 0·96 for ODSS total score; 0·99 and 0·82 for PDAI oral activity; 0·86 and 0·45 for ABSIS total; and 0·99 and 0·64 for PGA. Convergent validity was good, with a correlation coefficient > 0·5 (P < 0·001). The mean ± SD times taken to complete each scoring method were ODSS 76 ± 37 s, PDAI 117 ± 16 s and ABSIS 75 ± 19 s. CONCLUSIONS: This study has validated the ODSS for the assessment of oral PV. It has shown superior inter- and intraobserver reliability to PDAI, ABSIS and PGA and is quick to perform.

In-vivo imaging of the microvasculature of the soft tissue margins of osteonecrotic jaw lesions.

Introduction Given the increasing incidence of medication-related jaw osteonecrosis, and recognition of the mucosal blood supply's importance, we have developed a non-invasive Real Time Optical Vascular Imaging (RTOVI) instrument. Imaging the red blood cells within the sub-mucosal capillary networks demonstrates the microcirculatory anatomy. We report a small trial, demonstrating the technique's viability, examining mucosal microcirculatory changes adjacent to osteonecrotic lesions.Aims Imaging the microvasculature of soft tissue margins of patients' exposed necrotic bone lesions in situ was intended to provide unique observational as well as quantitative data, using an image analysis routine, based on ImageJ software. Our interest was to evaluate whether this could offer valuable information for complex wound margin management.Methods Four osteoradionecrosis and four medication-related osteonecrosis patients (M:F 1:1 mean 68.25 years) were enrolled under the NRES Ethics 11/LON/0354 and KCL Research Ethics Committee (REC) BDM/14/15-14 approvals. Microvascular images from mucosal margins of exposed mandibular osteonecrosis lesions were compared with equivalent images from both uninvolved contralateral mucosa and similar mucosal sites in four healthy subjects.Results We demonstrated narrow hypo-vascularised oedematous lesion margins surrounded by a concentric inflammatory band and normal mucosa beyond. Parameters reporting individual capillary shape, via mean percentage of occupancy per capillary per field of view and capillary loop aspect ratio, differed significantly between groups (ANOVA, p = 0.0002 and p = 0.04 respectively). Values reporting capillary number and area showed expected changes but did not reach statistical significance.Conclusion This pilot study demonstrated the feasibility of mucosal microvascular imaging in assessing the microvascular changes found in the soft tissues at the margins of osteonecrotic lesions, with potential to inform therapeutic interventions and clinical decisions to continue or modify regime strategies at the earliest opportunity. Given the increasing incidence of medication-related jaw osteonecrosis, and the recognition of the importance of mucosal blood supply, we developed a non-invasive instrument demonstrating microcirculation anatomy by imaging transiting red blood cells.

Rapid ex vivo examination of Mohs specimens using optical coherence tomography.

BACKGROUND: Mohs micrographic surgery (MMS) is an effective treatment for certain non-melanoma skin cancers. Optical coherence tomography (OCT) is a biomedical imaging modality that permits high-resolution imaging of the epidermis and dermis with the potential to detect both healthy tissue and tumour. OCT may also provide a means of detecting and differentiating between the various histological subtypes of basal cell carcinomas (BCC) in vivo. OBJECTIVE: The aim of this prospective ex vivo study was to evaluate the efficacy of OCT in recognising healthy and pathological margins of excised BCC lesions and detecting different BCC subtypes. METHODS: Seventy-three subjects with biopsy-proven BCCs on the facial region undergoing MMS were recruited. Narrow clinically healthy margins of the skin surrounding the tumour were included in the excisional biopsy. Biopsies were scanned with the OCT instrument immediately ex vivo and processed to obtain horizontal Mohs frozen sections and compared with their corresponding OCT images. RESULTS: Histopathological analysis of 280 margins showed 232 tumour free margins and 48 tumour-involved margins. OCT showed very good sensitivity (81.2%) and specificity (94.3%) in detecting healthy from tumour-involved margins. OCT accuracy was 93.4%, and the intra- and inter-observer reliability was substantial (Kappa value ranged between 0.63-0.76). CONCLUSION: This study shows the accuracy of ex vivo OCT in identifying the margin status of BCCs of the head and neck region. Moreover, this modality has demonstrated good capability in distinguishing different BCC subtypes and the potential for in vivo in situ diagnostics.

Rapid Bacterial Detection during Endodontic Treatment.

Bacteria present in the root canal (RC) space following an RC treatment (RCT) can lead to persistent infections, resulting in treatment failure and the need for reintervention or extraction. Currently, there are no standardized methods in use to clinically detect bacterial presence within RC spaces. The use of paper point sampling and fluorescence staining was shown to be a rapid method, able to detect residual bacteria following treatment. The study demonstrated that Calcein acetoxymethyl (AM) proved to be a suitable dye for detecting vital bacteria within mature endodontic biofilms, with an improved sensitivity over colony-forming unit counting in a stressed biofilm model. Furthermore, in a clinical trial with primary RCTs, 53 infected teeth were sampled in vivo, and increased detection of vital cells was found when compared with colony-forming unit counting, highlighting the sensitivity of the technique in detecting low cell numbers. By combining fluorescent staining and microspectroscopy with software-based spectral analysis, successful detection of vital cells from RCs was possible after 5 min of Calcein AM incubation. Application of this technology during RCT has the potential to reduce persistent infections through vital cell detection and additional treatment. Furthermore, this technique could be applied to antimicrobial research and disinfection control in clinical settings ( ClinicalTrials.gov NCT03055975).

Group O RBCs: where is universal donor blood being used.

BACKGROUND: There have been recurrent shortages of group O blood due to insufficient inventory and use of group O blood in ABO non-identical recipients. We performed a 12-year retrospective study to determine utilization of group O Rh-positive and Rh-negative red blood cells (RBCs) by recipient ABO group. Reasons for transfusing group O blood to ABO non-identical recipients were also assessed. METHODS: Utilization data from all group O Rh-positive and Rh-negative RBCs transfused at three academic hospitals between April 2002 and March 2014 were included. Data were extracted from Transfusion Registry for Utilization Surveillance and Tracking, a comprehensive database with inventory information on all blood products received at the hospitals. Extracted data included product type, ABO and Rh, final disposition (transfused, wasted, outdated), and demographic and clinical data on all patients admitted to hospital. Descriptive statistics were performed using sas 9.3. RESULTS: There were 314 968 RBC transfusions: 151 645 (48·1%) were group O, of which 138 136 (91·1%) RBC units were transfused to group O individuals. ABO non-identical recipients received 13 509 group O RBCs (8·9%). The percentage of group O RBCs transfused to ABO non-identical recipients by fiscal year varied from 7·8% to 11·1% with a steady increase from 2011 to 2013. Reasons for this included: trauma, outdating, outpatient usage and shortages. CONCLUSION: The practice of transfusing O RBCs to non-O individuals has been increasing. Specific hospital and blood supplier policies could be targeted to change practice, leading to a more sustainable group O red blood cell supply.

Statistical methods for incomplete data: Some results on model misspecification.

Inverse probability weighted estimating equations and multiple imputation are two of the most studied frameworks for dealing with incomplete data in clinical and epidemiological research. We examine the limiting behaviour of estimators arising from inverse probability weighted estimating equations, augmented inverse probability weighted estimating equations and multiple imputation when the requisite auxiliary models are misspecified. We compute limiting values for settings involving binary responses and covariates and illustrate the effects of model misspecification using simulations based on data from a breast cancer clinical trial. We demonstrate that, even when both auxiliary models are misspecified, the asymptotic biases of double-robust augmented inverse probability weighted estimators are often smaller than the asymptotic biases of estimators arising from complete-case analyses, inverse probability weighting or multiple imputation. We further demonstrate that use of inverse probability weighting or multiple imputation with slightly misspecified auxiliary models can actually result in greater asymptotic bias than the use of naïve, complete case analyses. These asymptotic results are shown to be consistent with empirical results from simulation studies.

Transfusion-related alloimmunization in children: epidemiology and effects of chemotherapy.

BACKGROUND & OBJECTIVES: Alloimmunization rates following red blood cell (RBC) transfusion in paediatric oncology are not known. This study aimed to: (1) describe frequency and specificity of alloantibodies in paediatric oncology patients after RBC transfusions; (2) determine the effect of chemotherapy on alloimmunization rate. MATERIALS & METHODS: Retrospective cohort study of paediatric patients at a tertiary care hospital is evaluated by two groups: control group, paediatric patients without cancer; study group, paediatric oncology patients who received chemotherapy. Alloimmunization was defined as clinically significant IgG alloantibody formation against RBC antigens. RESULTS: A total of 1273 children were evaluated including 324 in study group, 909 controls, and 40 haemoglobinopathy patients. Overall, frequency of alloimmunization was 1·5%: 0·3% (95% CI: 0, 1·90) in study group; 1·3% (95% CI: 0·73, 2·32) in control group and 15% in haemoglobinopathies. The association between chemotherapy and alloimmunization was not significant; P value = 0·20 Fisher's exact test, OR 0·23 (95% CI: 0·03, 1·79). CONCLUSION: This is the first study exploring RBC alloimmunization in paediatric patients by diagnosis. Alloimmunization frequency was low. It was not possible to determine an association between chemotherapy and alloimmunization due to the low event rate.

Multimodal optical characterisation of collagen photodegradation by femtosecond infrared laser ablation.

Collagen is a structural component of the human body, as a connective tissue it can become altered as a result of pathophysiological conditions. Although the collagen degradation mechanism is not fully understood, it plays an important role in ageing, disease progression and applications in therapeutic laser treatments. To fully understand the mechanism of collagen alteration, in our study photo-disruptive effects were induced in collagen I matrix by point-irradiation with a femtosecond Ti-sapphire laser under controlled laser ablation settings. This was followed by multi-modal imaging of the irradiated and surrounding areas to analyse the degradation mechanism. Our multi-modal methodology was based on second harmonic generation (SHG), scanning electron microscope (SEM), autofluorescence (AF) average intensities and the average fluorescence lifetime. This allowed us to quantitatively characterise the degraded area into four distinct zones: (1) depolymerised zone in the laser focal spot as indicated by the loss of SHG signal, (2) enhanced crosslinking zone in the inner boundary of the laser induced cavity as represented by the high fluorescence ring, (3) reduced crosslinking zone formed the outer boundary of the cavity as marked by the increased SHG signal and (4) native collagen. These identified distinct zones were in good agreement with the expected photochemical changes shown using Raman spectroscopy. In addition, imaging using polarisation-resolved SHG (p-SHG) revealed both a high degree of fibre re-orientation and a SHG change in tensor ratios around the irradiation spot. Our multi-modal optical imaging approach can provide a new methodology for defining distinct zones that can be used in a clinical setting to determine suitable thresholds for applying safe laser treatments without affecting the surrounding tissues. Furthermore this technique can be extended to address challenges observed in collagen based tissue engineering and used as a minimally invasive diagnostic tool to characterise diseased and non-diseased collagen rich tissues.

Microbiochemical analysis of carious dentine using Raman and fluorescence spectroscopy.

The aim of this study was to evaluate and correlate objectively the microspectroscopically derived biochemical components of sound, infected and affected carious dentine with their microhardness and autofluorescence (AF) characteristics. Over 3 million high-resolution Raman spectra from 8 extracted human carious teeth were recorded using Raman spectrometer with parallel spectrum acquisition. Green AF signals across each carious lesion from all samples were acquired with a similar spatial resolution using confocal fluorescence microscopy. The Knoop microhardness (KHN) from a total of 233 co-localized areas was recorded from the same samples and allocated subjectively into the three zones. Cluster analysis of the Raman data, performed using in-house software, produced five independent spectral components representing mineral content, protein content, porphyrin fluorescence (PF), putative infected dentine signal (IDS) and affected dentine signal (ADS). The distributions of the 5 Raman components and the AF signal were matched across all samples and their average values were calculated for each corresponding KHN area. The infected dentine was defined significantly by the KHN, AF and by the relative contribution of the mineral, PF and IDS clusters. Protein cluster was not statistically related to the KHN or AF. A delineation between affected and sound dentine was observed using the KHN, AF, PF and ADS parameters. This study concludes that micro-Raman spectroscopy can provide a non-invasive and objective evaluation of different carious dentine zones. Being able to detect and assess clinically the caries-affected dentine during minimally invasive operative caries management is important to control the risk of unnecessary tissue removal.

Clinical outcomes of patients with desmoplastic small round cell tumor of the peritoneum undergoing autologous HCT: a CIBMTR retrospective analysis.

Desmoplastic small round cell tumor of the peritoneum (DSRCTP) is a rare, frequently fatal tumor. This retrospective study, based on CIBMTR registry data, describes the largest reported cohort of DSRCTP patients who have undergone Auto-SCT. The probabilities of disease-free survival (DFS) at 1 year for patients in CR and not in CR were 75% (95% confidence interval: 48-94%) and 35% (15-59%), respectively. The probability of OS at 3 years was 57% (29-83%) and 28% (9-51%) for patients in CR and not in CR, respectively. Median survival for the entire cohort was 31 months (36 months and 21 months for those in CR and not in CR, respectively). Engraftment at 42 days was 97% (88-100%). Treatment-related mortality was low, with only one death in the first 100 days. Auto-SCT is a tolerable approach in patients with DSRCTP, with the greatest benefit seen in those patients who obtain CR. For those not in CR, the median OS in this series is greater than previously reported (21 months vs 17 months), suggesting Auto-SCT is useful in prolonging DFS and OS, even in patients with residual or persistent disease pre-transplant.

Prognostic variables for survival and skeletal complications in patients with multiple myeloma osteolytic bone disease.

Skeletal-related events (SREs) are common in patients with osteolytic lesions from multiple myeloma (MM), and result in substantial morbidity. We report herein a comprehensive, retrospective, multivariate analysis of prognostic factors for survival and first on-study SRE in MM patients using data from the phase III, randomized study comparing zoledronic acid with pamidronate in MM or breast cancer. Cox regression analyses were used to assess 22 variables for prognostic significance (defined as associations with P<0.05) in patients with bone metabolism marker assessments and complete baseline variable data. Of 510 evaluable MM patients, 282 had complete covariate information and were included in models. Reduced Cox multivariate models identified five significant prognostic factors for first SRE (weight, race, high N-terminal cross-linked telopeptide of type I collagen (NTX), high pain score, and need for narcotic analgesics) and seven for survival (age, SRE history, myeloma subtype, anemia, high lactate dehydrogenase, high NTX, and low albumin levels). High NTX was the only variable associated with elevated risks of both first SRE and death (P< or =0.02 for each). These analyses identified prognostic factors for SREs and survival in patients with MM. Taken together with current staging systems, these factors could further facilitate decision making for optimal treatment of myeloma bone disease, although further prospective assessments are needed.

An in vitro evaluation of microtensile bond strengths of two adhesive bonding agents to residual dentine after caries removal using three excavation techniques.

OBJECTIVES: To assess amounts of residual dentine retained after using three excavation techniques; the microtensile bond strengths (microTBS) to residual dentine, comparing etch-rinse vs. self-etching adhesives. METHODS: 42 carious molars were subdivided (N=21) dependent upon adhesive/composite system (Adper Scotchbond 1XT and Filtek Supreme vs. Filtek Silorane adhesive and composite). Dividing into three (N=7), dependent upon caries excavation technique employed (hand vs. chemo-mechanical: Carisolv gel vs. experimental enzymatic gel (SFC-V)), caries removal was assessed using visual/tactile criteria and in situ autofluorescence (AF) confocal fibre-optic micro-endoscopy (CFOME). Post-restoration/four-week hydrated storage, four 0.9 mm(2) beams per tooth underwent microTBS testing/microscopic analysis of fractured surfaces. Three cavities from each excavation group were analysed using SEM. RESULTS: SEM revealed surface roughness with smear layer occluding tubule orifices in hand-excavated samples and a reduced, variable smear layer for both chemo-mechanical systems. CFOME AF assessment indicated hand excavation left sound dentine, Carisolv left affected dentine and SFC-V slightly under-prepared clinically. Mean microTBS values from etch-rinse samples (27 MPa (SD 3.9), hand; 22 MPa (SD 5.1), Carisolv; 26 MPa (SD 4.4), SFC-V) showed statistical differences between hand and Carisolv groups. Mean microTBS data for self-etch samples (22 MPa (SD 3.3), hand; 27 MPa (SD 6.1), Carisolv; 25 MPa (SD 4.7), SFC-V) showed significant differences between hand and Carisolv, and hand vs. SFC-V. Failure loci distribution in etch-rinse samples was between dentine-adhesive, within adhesive and within composite whereas self-etch samples exhibited failure predominantly between adhesive and composite. CONCLUSIONS: Data indicated that all null hypotheses were disproved.

Anti-PF4/heparin antibody formation postorthopedic surgery thromboprophylaxis: the role of non-drug risk factors and evidence for a stoichiometry-based model of immunization.

BACKGROUND: Heparin-induced thrombocytopenia is an antibody-mediated disorder exhibiting variable frequency in different clinical settings. Antibodies recognize PF4/heparin complexes formed at optimal stoichiometric molar ratios. OBJECTIVE: To identify clinical factors influencing risk of anti-PF4/heparin immunization. PATIENTS/METHODS: We performed observational studies and exploratory analyses of the frequency of anti-PF4/heparin antibody formation in 6324 patients who received enoxaparin or fondaparinux in four randomized controlled trials of postorthopedic surgery thromboprophylaxis. Variables included surgery type (knee vs. hip), timing of first anticoagulant dose (pre- vs. postsurgery), circumstances of surgery (elective vs. hip fracture), anticoagulant (enoxaparin vs. fondaparinux) and body-mass index (BMI). We applied a stoichiometry-based model that predicts immunization risk based on expected differences in PF4/anticoagulant ratios in different settings, and specifically used this model to predict the effect of increasing BMI quartiles upon relative risk (RR) of immunization for fondaparinux vs. enoxaparin. RESULTS: Anti-PF4/heparin immunization was more frequent after knee vs. hip surgery (particularly for enoxaparin), and when enoxaparin was given post- rather than pre-elective surgery; however, the opposite occurred with hip fracture surgery, that is, antibody formation was more frequent when enoxaparin or fondaparinux was given presurgery. The RR of immunization for fondaparinux vs. enoxaparin decreased significantly for increasing BMI quartiles, an effect predominantly because of increasing immunization with enoxaparin at increasing BMI quartiles. CONCLUSIONS: Several non-drug factors--including type and circumstances of surgery, timing of first anticoagulant dose and BMI--influence risk of anti-PF4/heparin antibody formation, consistent with a stoichiometry-based immunization model of PF4 and anticoagulant ratios occurring during the early peri-operative period.

Diagnostic utility of light transmission platelet aggregometry: results from a prospective study of individuals referred for bleeding disorder assessments.

BACKGROUND: Light transmission aggregometry (LTA) is commonly performed to assess individuals for bleeding disorders. OBJECTIVES: The goal was to evaluate the incidence and spectrum of platelet function abnormalities in a prospective cohort of individuals referred for bleeding disorder assessments after exclusion of thrombocytopenia and von Willebrand disease. PATIENTS/METHODS: Subjects were healthy controls and patients from a prospective cohort of individuals referred for bleeding disorder assessments after exclusion of thrombocytopenia and von Willebrand disease. LTA was performed by standardized methods using platelet-rich plasma adjusted to 250x10(9) platelets L(-1). Maximal aggregation data were analyzed to determine the likelihood of detecting a platelet function disorder by LTA, and the sensitivity and specificity of LTA for platelet disorders. RESULTS: The incidence of false positive LTA among subjects excluded of having bleeding disorders was similar to healthy controls. Abnormal LTA was more common in subjects with bleeding disorders and the likelihood of a bleeding disorder was significantly increased (odds ratio 32) when maximal aggregation was reduced with two or more agonists. Receiver operator curve analyses indicated that LTA had high specificity and moderate sensitivity for detecting inherited defects in platelet function and that the LTA agonists 1.25 microg mL(-1) collagen, 6 microM epinephrine, 1.6 mM arachidonic acid and 1.0 microM thromboxane analogue U44619 detected most inherited disorders with abnormal LTA. CONCLUSIONS: LTA is valuable for detecting platelet function abnormalities among individuals referred for bleeding problems, particularly when the test indicates abnormal responses to multiple agonists.

Second auto-SCT is safe and effective salvage therapy for relapsed multiple myeloma.

Therapeutic options for patients with multiple myeloma whose disease has relapsed after a prior auto-SCT include novel biologic therapies, traditional chemotherapy or a second transplant, with no clear standard of care. Few published studies address the safety and efficacy of a second auto-SCT for relapsed disease. We reviewed the Abramson Cancer Center experience with salvage auto-SCT for relapsed multiple myeloma. Forty-one patients had received a salvage auto-SCT at our institution; the median time between transplants was 37 months (range 3-91). The overall response rate in assessable patients was 55%, and treatment-related mortality was 7%. With a median follow-up time of 15 months, the median PFS was 8.5 months and the median overall survival (OS) was 20.7 months. In a multivariate analysis of OS, independent prognostic factors were >or=5 prior lines of therapy and time to progression after initial auto-SCT of