The role of cadaveric simulation in talus fracture research: A scoping review

BACKGROUND

Talus fractures are rare (<1% of all fractures), and their rarity limits the number of studies available to guide management. In instances such as this, cadaveric studies can play an important role. The purpose of this scoping review was to identify and describe the current body of literature on cadaveric studies of fractures of the talus.

METHODS

Through multiple electronic database searches (Medline, Embase, Scopus) we identified a broad body of cadaveric research into talus fractures, and these were classified into 4 main themes. Study characteristics were summarised along with any descriptive results and conclusions.

RESULTS

The search yielded 484 articles of which 19 met the inclusion criteria. They provide valuable insights into benefits and drawbacks of surgical approaches to the talus, particularly with regard to direct visualisation of anatomic reduction, and risks of neurovascular or tendon compromise. For talar neck fractures it is clear that cannulated screws offer superior fixation over plates, however, are inferior when considering anatomic reduction of the fracture. Direct visualisation of fracture reduction is far superior to intraoperative radiographic assessment, and mal-reduction leads to reduced subtalar joint range of motion, midfoot deformity, and increased joint contact pressures.

CONCLUSIONS

This study provides a summary of the existing literature surrounding the use of cadaver studies in fractures of the talus. We have identified gaps in the literature, particularly surrounding strength of fixation of new locking plate fixation techniques.

Urethro-venous fistula following straddle injury: A case report and image series

We present a case of a 49-year-old man with an acute traumatic urethral injury after a fall onto a fence post. Retrograde contrast study showed a contrast leak and suspicion of a traumatic urethro-venous fistula.

We successfully placed a urethral indwelling catheter (IDC) in the operating room and follow-up urethrocystoscopy showed healing of the injury. The patient remained asymptomatic during further follow-up visits.

Anterior cervical osteophytes causing dysphagia and dyspnoea

A 75-year-old man presents to his general practitioner (GP) with dyspnoea, and dysphagia to liquids and solids, with regurgitation causing recurrent episodes of dyspnoea. He had a background of osteoarthritis, was an ex heavy smoker and had undergone coronary artery bypass graft five years previously. After several emergency admissions, initial investigation by the GP, and referral to ear, nose and throat specialists with no cause for dysphagia found, he underwent computed tomography imaging of the neck and thorax which demonstrated large cervical osteophytes at the level of C3-C4. He was referred to spinal orthopaedics and after multidisciplinary team discussion the cervical osteophytes were removed via an anterior approach, resulting in complete resolution of his symptoms.

Development and Interrogation of a Transcriptomic Resource for the Giant Triton Snail (Charonia tritonis)

Gastropod molluscs are among the most abundant species that inhabit coral reef ecosystems. Many are specialist predators, along with the giant triton snail Charonia tritonis (Linnaeus, 1758) whose diet consists of Acanthaster planci (crown-of-thorns starfish), a corallivore known to consume enormous quantities of reef-building coral. C. tritonis are considered vulnerable due to overexploitation, and a decline in their populations is believed to have contributed to recurring A. planci population outbreaks. Aquaculture is considered one approach that could help restore natural populations of C. tritonis and mitigate coral loss; however, numerous questions remain unanswered regarding their life cycle, including the molecular factors that regulate their reproduction and development. In this study, we have established a reference C. tritonis transcriptome derived from developmental stages (embryo and veliger) and adult tissues. This was used to identify genes associated with cell signalling, such as neuropeptides and G protein-coupled receptors (GPCRs), involved in endocrine and olfactory signalling. A comparison of developmental stages showed that several neuropeptide precursors are exclusively expressed in post-hatch veligers and functional analysis found that FFamide stimulated a significant (20.3%) increase in larval heart rate. GPCRs unique to veligers, and a diversity of rhodopsin-like GPCRs located within adult cephalic tentacles, all represent candidate olfactory receptors. In addition, the cytochrome P450 superfamily, which participates in the biosynthesis and degradation of steroid hormones and lipids, was also found to be expanded with at least 91 genes annotated, mostly in gill tissue. These findings further progress our understanding of C. tritonis with possible application in developing aquaculture methods.

Norwich COVID-19 testing initiative pilot: evaluating the feasibility of asymptomatic testing on a university campus

Background

There is a high prevalence of COVID-19 in university-age students, who are returning to campuses. There is little evidence regarding the feasibility of universal, asymptomatic testing to help control outbreaks in this population. This study aimed to pilot mass COVID-19 testing on a university research park, to assess the feasibility and acceptability of scaling up testing to all staff and students.

Methods

This was a cross-sectional feasibility study on a university research park in the East of England. All staff and students (5625) were eligible to participate. All participants were offered four PCR swabs, which they self-administered over two weeks. Outcome measures included uptake, drop-out rate, positivity rates, participant acceptability measures, laboratory processing measures, data collection and management measures.

Results

798 (76%) of 1053 who registered provided at least one swab; 687 (86%) provided all four; 792 (99%) of 798 who submitted at least one swab had all negative results and 6 participants had one inconclusive result. There were no positive results. 458 (57%) of 798 participants responded to a post-testing survey, demonstrating a mean acceptability score of 4.51/5, with five being the most positive.

Conclusions

Repeated self-testing for COVID-19 using PCR is feasible and acceptable to a university population.

Regulator of G protein signaling 5 restricts neutrophil chemotaxis and trafficking

Neutrophils are white blood cells that are mobilized to damaged tissues and to sites of pathogen invasion, providing the first line of host defense. Chemokines displayed on the surface of blood vessels promote migration of neutrophils to these sites, and tissue- and pathogen-derived chemoattractant signals, including N-formylmethionylleucylphenylalanine (fMLP), elicit further migration to sites of infection. Although nearly all chemoattractant receptors use heterotrimeric G proteins to transmit signals, many of the mechanisms lying downstream of chemoattractant receptors that either promote or limit neutrophil motility are incompletely defined. Here, we show that regulator of G protein signaling 5 (RGS5), a protein that modulates G protein activity, is expressed in both human and murine neutrophils. We detected significantly more neutrophils in the airways of Rgs5^-/- mice than WT counterparts following acute respiratory virus infection and in the peritoneum in response to injection of thioglycollate, a biochemical proinflammatory stimulus. RGS5-deficient neutrophils responded with increased chemotaxis elicited by the chemokines CXC motif chemokine ligand 1 (CXCL1), CXCL2, and CXCL12 but not fMLP. Moreover, adhesion of these cells was increased in the presence of both CXCL2 and fMLP. In summary, our results indicate that RGS5 deficiency increases chemotaxis and adhesion, leading to more efficient neutrophil mobilization to inflamed tissues in mice. These findings suggest that RGS5 expression and activity in neutrophils determine their migrational patterns in the complex microenvironments characteristic of inflamed tissues.

Well-posed continuum equations for granular flow with compressibility and μ(I)-rheology

Continuum modelling of granular flow has been plagued with the issue of ill-posed dynamic equations for a long time. Equations for incompressible, two-dimensional flow based on the Coulomb friction law are ill-posed regardless of the deformation, whereas the rate-dependent μ(I)-rheology is ill-posed when the non-dimensional inertial number I is too high or too low. Here, incorporating ideas from critical-state soil mechanics, we derive conditions for well-posedness of partial differential equations that combine compressibility with I-dependent rheology. When the I-dependence comes from a specific friction coefficient μ(I), our results show that, with compressibility, the equations are well-posed for all deformation rates provided that μ(I) satisfies certain minimal, physically natural, inequalities.

The Reliability of a Pre-Loaded Treadmill Time-Trial in Moderate Normobaric Hypoxia

The purpose of this study was to assess the reliability of a pre-loaded 1 500-m treadmill time trial, conducted in moderate normobaric hypoxia. 8 trained runners/triathletes (24±3 years, 73.2±8.1 kg, 182.5±6.5 cm, altitude specific V˙O2max: 52.9±5.5 ml·kg(-1)·min(-1)) completed 3 trials (the first as a familiarisation), involving 2, 15-min running bouts at 45% and 65% V˙O2max, respectively, and a 1 500-m time trial in moderate normobaric hypoxia equivalent to a simulated altitude of 2 500 m (FiO2~15%). Heart rate, arterial oxygen saturation, skeletal muscle and cerebral tissue oxygenation (StO2), expired gas ( V˙O2 and V˙CO2), and ratings of perceived exertion were monitored. Running performance (Trial 1: 352.7±40; Trial 2: 353.9±38.2 s) demonstrated a low CV (0.9%) and high ICC (1). All physiological variables demonstrated a global CV≤4.2%, and ICC≥0.87, with the exception of muscle (CV 10.4%; ICC 0.70) and cerebral (CV 4.1%; ICC 0.82) StO2. These data demonstrate good reliability of the majority of physiological variables and indicate that a pre-loaded 1 500-m time trial conducted in moderate normobaric hypoxia is a highly reliable test of performance.

Management and closure of the open abdomen after damage control laparotomy for trauma. A systematic review and meta-analysis

INTRODUCTION

Damage control laparotomy for trauma (DCL) entails immediate control of haemorrhage and contamination, temporary abdominal closure (TAC), a period of physiological stabilisation, then definitive repair of injuries. Although immediate primary fascial closure is desired, fascial retraction and visceral oedema may dictate an alternate approach. Our objectives were to systematically identify and compare methods for restoration of fascial continuity when primary closure is not possible following DCL for trauma, to simplify these into a standardised map, and describe the ideal measures of process and outcome for future studies.

METHODS

Cochrane, OVID (Medline, AMED, Embase, HMIC) and PubMed databases were accessed using terms: (traum*, damage control, abbreviated laparotomy, component separation, fascial traction, mesh closure, planned ventral hernia (PVH), and topical negative pressure (TNP)). Randomised Controlled Trials, Case Series and Cohort Studies reporting TAC and early definitive closure methods in trauma patients undergoing DCL were included. Outcomes were mortality, days to fascial closure, hospital length of stay, abdominal complications and delayed ventral herniation.

RESULTS

26 studies described and compared early definitive closure methods; delayed primary closure (DPC), component separation (CS) and mesh repair (MR), among patients with an open abdomen after DCL for trauma. A three phase map was developed to describe the temporal and sequential attributes of each technique. Significant heterogeneity in nomenclature, terminology, and reporting of outcomes was identified. Estimates for abdominal complications in DPC, MR and CS groups were 17%, 41% and 17% respectively, while estimates for mortality in DPC and MR groups were 6% and 0.5% (data heterogeneity and requirement of fixed and random effects models prevented significance assessment). Estimates for abdominal closure in the MR and DPC groups differed; 6.30 (95% CI=5.10-7.51), and 15.90 (95% CI=9.22-22.58) days respectively. Reporting poverty prevented subgroup estimate generation for ventral hernia and hospital length of stay.

CONCLUSION

Component separation or mesh repair may be valid alternatives to delayed primary closure following a trauma DCL. Comparisons were hampered by the lack of uniform reporting and bias. We propose a new system of standardised nomenclature and reporting for further investigation and management of the post-DCL open abdomen.

Eosinophil-associated ribonuclease 11 is a macrophage chemoattractant

RNase A is the prototype of an extensive family of divergent proteins whose members share a unique disulfide-bonded tertiary structure, conserved catalytic motifs, and the ability to hydrolyze polymeric RNA. Several members of this family maintain independent roles as ribonucleases and modulators of innate immunity. Here we characterize mouse eosinophil-associated RNase (Ear) 11, a divergent member of the eosinophil ribonuclease cluster, and the only known RNase A ribonuclease expressed specifically in response to Th2 cytokine stimulation. Mouse Ear 11 is differentially expressed in somatic tissues at baseline (brain ≪ liver < lung < spleen); systemic stimulation with IL-33 results in 10-5000-fold increased expression in lung and spleen, respectively. Ear 11 is also expressed in response to protective priming of the respiratory mucosa with Lactobacillus plantarum; transcripts are detected both locally in lung as well as systemically in bone marrow and spleen. Mouse Ear 11 is enzymatically active, although substantially less so than mEar 1 and mEar 2; the relative catalytic efficiency (kcat/Km) of mEar 11 is diminished ∼1000-1500-fold. However, in contrast to RNase 2/EDN and mEar 2, which have been characterized as selective chemoattractants for CD11c(+) dendritic cells, mEar 11 has prominent chemoattractant activity for F4/80(+)CD11c(-) tissue macrophages. Chemoattractant activity is not dependent on full enzymatic activity, and requires no interaction with the pattern recognition receptor, Toll-like receptor 2 (TLR2). Taken together, this work characterizes a divergent RNase A ribonuclease with a unique expression pattern and function, and highlights the versatility of this family in promoting innate immunity.

Vertical rectus abdominis myocutaneous flap reconstruction of the perineal defect after abdominoperineal excision is associated with low morbidity

AIM

To examine the short-term outcomes of perineal reconstruction with a vertical rectus abdominis myocutaneous (VRAM) flap following abdominoperineal excision (APE).

METHOD

Retrospective case note review of all patients undergoing APE and primary VRAM reconstruction between July 2001 and February 2012 in a district general hospital tertiary referral centre for APE. Complications were categorized using the Clavien-Dindo classification, which grades complications from I to V in order of increasing severity.

RESULTS

Fifty-five consecutive patients (31 men, median age 65, range 38-84 years) underwent APE with VRAM flap reconstruction, 15 for anal cancer and 40 for rectal cancer. Median length of stay was 11 days but was significantly shorter in the laparoscopic group compared with the open group (8 vs 12 days; P < 0.01) and in patients who did not experience any complications (P < 0.05). Four patients (7%) had major complications (Grade 3 and above) directly related to the flap or donor site.

CONCLUSION

VRAM reconstruction of the perineum can be safely performed following APE with results that compare favourably with other techniques. Most flap complications are minor, although these are still associated with an increase in the length of hospital stay.

Naive T cells sense the cysteine protease allergen papain through protease-activated receptor 2 and propel TH2 immunity

BACKGROUND

Sensitization to protease allergens, such as papain, or helminth infection is associated with basophil recruitment to draining lymph nodes (LNs). Basophils have the capacity to present antigen to naive T cells and promote T(H)2 differentiation directly or indirectly through IL-4 production.

OBJECTIVE

We studied how papain induces basophil migration to LNs and the contribution of various leukocytes to papain-induced immune responses.

METHODS

We immunized mice in the footpad with papain and studied leukocyte recruitment and inflammatory cytokine and chemokine production in the draining popliteal LNs.

RESULTS

Papain directly activated naive T cells through protease-activated receptor (PAR) 2 to initiate a chemokine/cytokine program that includes CCL17, CCL22, and IL-4. Papain-triggered innate immune responses were dependent on both CD4 T cells and PAR2 and were strongly reduced in the absence of CCR4, the primary receptor for CCL17/CCL22.

CONCLUSION

These results elucidate a novel innate allergen-recognition pathway mediated by naive T cells through PAR2, which provide an immediate source of chemokines and IL-4 upstream of basophils and antigen-restricted T(H)2 differentiation. PAR2 antagonism might thus hold promise for the treatment of allergic disease.

IL-1α modulates neutrophil recruitment in chronic inflammation induced by hydrocarbon oil

Exposure to naturally occurring hydrocarbon oils is associated with the development of chronic inflammation and a wide spectrum of pathological findings in humans and animal models. The mechanism underlying the unremitting inflammatory response to hydrocarbons remains largely unclear. The medium-length alkane 2,6,10,14 tetramethylpentadecane (also known as pristane) is a hydrocarbon that potently elicits chronic peritonitis characterized by persistent infiltration of neutrophils and monocytes. In this study, we reveal the essential role of IL-1α in sustaining the chronic recruitment of neutrophils following 2,6,10,14 tetramethylpentadecane treatment. IL-1α and IL-1R signaling promote the migration of neutrophils to the peritoneal cavity in a CXCR2-dependent manner. This mechanism is at least partially dependent on the production of the neutrophil chemoattractant CXCL5. Moreover, although chronic infiltration of inflammatory monocytes is dependent on a different pathway requiring TLR-7, type I IFN receptor, and CCR2, the adaptor molecules MyD88, IL-1R-associated kinase (IRAK)-4, IRAK-1, and IRAK-2 are shared in regulating the recruitment of both monocytes and neutrophils. Taken together, our findings uncover an IL-1α-dependent mechanism of neutrophil recruitment in hydrocarbon-induced peritonitis and illustrate the interactions of innate immune pathways in chronic inflammation.

Melanomacrophages in three species of free-ranging sharks from the northwestern Atlantic, the blue shark Prionacae glauca (L.), the shortfin mako, Isurus oxyrhinchus Rafinesque, and the thresher, Alopias vulpinus (Bonnaterre)

The melanomacrophage aggregates or cells (MMC) are commonly used as biomarkers of exposure to pollution in fish, albeit their numbers and morphological characteristics can be influenced not only by environmental toxins but also by a range of physiological parameters and pathological conditions. Accordingly, before we can use MMC as biomarkers in any fish species, their normal, 'background' characteristics have to be established in apparently healthy fish. The knowledge of MMC in sharks is minimal. The aim of this study was to characterize MMC from 51 free-ranging, large pelagic sharks from the northwestern Atlantic, including shortfin mako, Isurus oxyrhinchus, thresher, Alopias vulpinus and blue shark, Prionacae glauca. The rationale of this study was twofold. First, because, sharks have life histories predisposing them to the accumulation of environmental toxins they constitute good sentinel species of the health of the global marine ecosystem. Second, because many shark populations are in decline or threatened by extinction, we need to expand our understanding of their health status in order to develop appropriate protective measures. All sharks were collected by sports fishing gear between June and August in 2007. Their health condition was assessed by necropsy, morphometrics, and by microscopic examination of gonads, livers, spleens and kidneys. Routine, haematoxylin and eosin and/or Pearl's reagent-stained paraffin embedded sections were studied by light microscopy. Our results provide the first data on the morphometric and morphological characteristics of MMC in viscera of apparently healthy free-ranging sharks from the northwestern Atlantic.

Early clinical failure of the Birmingham metal-on-metal hip resurfacing is associated with metallosis and soft-tissue necrosis

The rate and mode of early failure in 463 Birmingham hip resurfacings in a two-centre, multisurgeon series were examined. Of the 463 patients two have died and three were lost to follow-up. The mean radiological and clinical follow-up was for 43 months (6 to 90).

We have revised 13 resurfacings (2.8%) including seven for pain, three for fracture, two for dislocation and another for sepsis. Of these, nine had macroscopic and histological evidence of metallosis. The survival at five years was 95.8% (95% confidence interval (CI) 94.1 to 96.8) for revision for all causes and 96.9% (95% CI 95.5 to 98.3) for metallosis.

The rate of metallosis related revision was 3.1% at five years. Risk factors for metallosis were female gender, a small femoral component, a high abduction angle and obesity. We do not advocate the use of the Birmingham Hip resurfacing procedure in patients with these risk factors.

TLR7-dependent and FcgammaR-independent production of type I interferon in experimental mouse lupus

Increased type I interferon (IFN-I) production and IFN-stimulated gene (ISG) expression are linked to the pathogenesis of systemic lupus erythematosus (SLE). Although the mechanisms responsible for dysregulated IFN-I production in SLE remain unclear, autoantibody-mediated uptake of endogenous nucleic acids is thought to play a role. 2,6,10,14-tetramethylpentadecane (TMPD; also known as pristane) induces a lupus-like disease in mice characterized by immune complex nephritis with autoantibodies to DNA and ribonucleoproteins. We recently reported that TMPD also causes increased ISG expression and that the development of the lupus is completely dependent on IFN-I signaling (Nacionales, D.C., K.M. Kelly-Scumpia, P.Y. Lee, J.S. Weinstein, R. Lyons, E. Sobel, M. Satoh, and W.H. Reeves. 2007. Arthritis Rheum. 56:3770–3783). We show that TMPD elicits IFN-I production, monocyte recruitment, and autoantibody production exclusively through a Toll-like receptor (TLR) 7– and myeloid differentiation factor 88 (MyD88)–dependent pathway. In vitro studies revealed that TMPD augments the effect of TLR7 ligands but does not directly activate TLR7 itself. The effects of TMPD were amplified by the Y-linked autoimmune acceleration cluster, which carries a duplication of the TLR7 gene. In contrast, deficiency of Fcγ receptors (FcγRs) did not affect the production of IFN-I. Collectively, the data demonstrate that TMPD-stimulated IFN-I production requires TLR7/MyD88 signaling and is independent of autoantibody-mediated uptake of ribonucleoproteins by FcγRs.

The role of B-cell subsets in pristane-induced lupus (130.14)

An intraperitoneal (ip) injection of pristane in mice induces a biphasic immune response characterized by an early T-independent phase (increased total IgM, IgM anti-ssDNA peaking at 2 wks) and a later T-dependent phase (increased total IgG, IgG anti-snRNPs, Su, chromatin after 4–6 wks). Although peritoneal B-1 cells are thought to be responsible for the early phase, they disappear after ip pristane. IgG autoantibodies can be produced in SCID mice by transferring peritoneal, spleen, or lymph node cells from pristane-treated mice. To evaluate further the role of B-cell subsets in the two phases of pristane-induced autoimmunity, GFP+ naïve peritoneal, spleen, or bone marrow (bm) cells were transferred ip to T- and B-cell deficient RAG1−/− mice, followed by an ip pristane 3 days later. Autoantibodies and total Ig (ELISA), and the phenotypes of GFP+ cells in the recipients (flow cytometry) were analyzed. At 3 days prior to pristane ip, GFP+ peritoneal B-1 cells (CD19+CD11b+ CD5+ IgM+) were detected in recipients of bm, peritoneal, or spleen cells. Following pristane ip, peritoneal B-1 cells disappeared, as seen in immunocompetent mice. Analysis of GFP+ cells in peritoneal cavity at day 10 revealed the predominance of CD11b+ macrophages in the peritoneal cell recipients whereas T and B cells were predominant in bm or spleen cell recipients. In mice that received GFP+ spleen cells, IgM anti-ss- and -dsDNA dramatically increased at 2–4 weeks after pristane, while the total IgM levels increased in all groups at later time points. We conclude that splenic B cells may be responsible for the early IgM response in pristane model.

Supported by NIH

Autoantibodies against the replication protein A complex in systemic lupus erythematosus and other autoimmune diseases

Replication protein A (RPA), a heterotrimer with subunits of molecular masses 70, 32, and 14 kDa, is a single-stranded-DNA-binding factor involved in DNA replication, repair, and recombination. There have been only three reported cases of anti-RPA in systemic lupus erythematosus (SLE) and Sjögren syndrome (SjS). This study sought to clarify the clinical significance of autoantibodies against RPA. Sera from 1,119 patients enrolled during the period 2000 to 2005 were screened by immunoprecipitation (IP) of ³⁵S-labeled K562 cell extract. Antigen-capture ELISA with anti-RPA32 mAb, immunofluorescent antinuclear antibodies (ANA) and western blot analysis with purified RPA were also performed. Our results show that nine sera immunoprecipitated the RPA70–RPA32–RPA14 complex and all were strongly positive by ELISA (titers 1:62,500 to 1:312,500). No additional sera were positive by ELISA and subsequently confirmed by IP or western blotting. All sera showed fine speckled/homogeneous nuclear staining. Anti-RPA was found in 1.4% (4/276) of SLE and 2.5% (1/40) of SjS sera, but not in rheumatoid arthritis (0/35), systemic sclerosis (0/47), or polymyositis/dermatomyositis (0/43). Eight of nine patients were female and there was no racial predilection. Other positive patients had interstitial lung disease, autoimmune thyroiditis/hepatitis C virus/pernicious anemia, or an unknown diagnosis. Autoantibody specificities found in up to 40% of SLE and other diseases, such as anti-nRNP, anti-Sm, anti-Ro, and anti-La, were unusual in anti-RPA-positive sera. Only one of nine had anti-Ro, and zero of nine had anti-nRNP, anti-Sm, anti-La, or anti-ribosomal P antibodies. In summary, high titers of anti-RPA antibodies were found in nine patients (1.4% of SLE and other diseases). Other autoantibodies found in SLE were rare in this subset, suggesting that patients with anti-RPA may form a unique clinical and immunological subset.

Increased natural CD4+CD25+ regulatory T cells and their suppressor activity do not contribute to mortality in murine polymicrobial sepsis

Regulatory T cells (Tregs), including natural CD4+CD25+ Tregs and inducible IL-10 producing T regulatory type 1 (T(R)1) cells, maintain tolerance and inhibit autoimmunity. Recently, increased percentages of Tregs have been observed in the blood of septic patients, and ex vivo-activated Tregs were shown to prevent polymicrobial sepsis mortality. Whether endogenous Tregs contribute to sepsis outcome remains unclear. Polymicrobial sepsis, induced by cecal ligation and puncture, caused an increased number of splenic Tregs compared with sham-treated mice. Splenic CD4+CD25+ T cells from septic mice expressed higher levels of Foxp3 mRNA and were more efficient suppressors of CD4+CD25- T effector cell proliferation. Isolated CD4+ T cells from septic mice displayed increased intracellular IL-10 staining following stimulation, indicating that T(R)1 cells may also be elevated in sepsis. Surprisingly, Ab depletion of total CD4+ or CD4+CD25+ populations did not affect mortality. Furthermore, no difference in survival outcome was found between CD25 or IL-10 null mice and wild-type littermates, indicating that Treg or T(R)1-generated IL-10 are not required for survival. These results demonstrate that, although sepsis causes a relative increase in Treg number and increases their suppressive function, their presence does not contribute significantly to overall survival in this model.

Peptide-pulsed immature dendritic cells reduce response to beta cell target antigens and protect NOD recipients from type I diabetes

Our previous work demonstrated peptide-pulsed mature myeloid dendritic cells (DC) presenting beta cell antigens induce tolerance. Here we determine whether immature DC (iDC) presenting dominant (insulin beta9-23 chain, proinsulin C19-A3) or ignored (glutamic acid decarboxylase 65(78-97)) antigen determinants promote tolerance. Nonobese diabetic (NOD) mice were given injections of either unpulsed or peptide-pulsed myeloid iDC beginning at 9 weeks of age for 3 consecutive weeks. Diabetes incidence in recipients of unpulsed iDC was comparable to unmanipulated animals ( approximately 80%), whereas GAD65(78-97) pulsed iDC recipients were protected from the disease (P = 0.05). We also analyzed splenic T cell proliferation responses to the panel of studied peptides in diabetic and nondiabetic recipients. When stimulated with insulin or proinsulin peptide, nondiabetic mice receiving the peptide-pulsed iDC had a 21- to 31-fold or 3.9- to 9.0-fold reduction in T cell response, respectively, as compared to the response of diabetic unpulsed recipients. However, only a 2.6- to 3.1-fold reduction in response to beta chain peptide, and a 1.5- to 3.4-fold reduction in proinsulin response were observed in diabetic mice receiving peptide-pulsed iDC. The reduction was not specific to the immunizing peptide, as reduced proliferation was observed to other diabetes-target peptides. We conclude that protective iDC-based therapies require target antigen presentation, and ignored determinants may be preferable perhaps due to an available naïve T cell repertoire. In addition, iDC presenting peptides induce a nonspecific reduction in T cell responses to beta cell antigens, possibly through the induction of regulatory T cells.

Autoantibodies to RNA helicase A: A new serologic marker of early lupus

OBJECTIVE

To investigate the clinical and immunologic significance of autoantibodies to RNA helicase A (RHA) in patients with systemic rheumatic diseases.

METHODS

The study group comprised 1,119 individuals enrolled in the University of Florida Center for Autoimmune Diseases registry from 2000 to 2005. Diagnoses were based on standard criteria. Autoantibodies were analyzed by immunoprecipitation and Western blot assays.

RESULTS

Anti-RHA was observed in 17 (6.2%) of 276 patients with systemic lupus erythematosus (SLE), 2 patients with antiphospholipid antibodies, and 3 other patients, but anti-RHA was not observed in any patient with polymyositis/dermatomyositis, systemic sclerosis, rheumatoid arthritis, or Sjögren's syndrome. Anti-RHA was present in only 2.9% of African American patients, compared with 6.0% of white patients and 12-25% of patients of other races; this was in striking contrast to the frequency of anti-Sm in African American patients (27.2%). Among patients with SLE, anti-RHA was common in young patients (26% of those whose initial visit was at an age younger than 20 years versus 3-4% of those who were initially seen at ages 20-49 years) and at an early stage of disease (23% of those whose first clinic visit was within 1 year of disease onset versus 2-8% of those whose first visit was at least 1 year after disease onset). In 9 of 11 patients, levels of anti-RHA decreased to <10% of the initial value within 9-37 months, while levels of coexisting anti-Ro or anti-Su remained the same. New specificities developed in 2 patients (anti-nuclear RNP and anti-Sm, and anti-ribosomal P, respectively). These data suggest that the level of anti-RHA diminishes over time, and that anti-RHA is regulated via a mechanism different from that for other lupus-related autoantibodies.

CONCLUSION

Anti-RHA is a new serologic marker for SLE. It is produced mainly in young non-African Americans at an early stage of their disease. Anti-RHA has a unique tendency to diminish over time. The production of anti-RHA may depend on a process restricted to early SLE, or it may be highly sensitive to treatment.

Nucleolar staining cannot be used as a screening test for the scleroderma marker anti–RNA polymerase I/III antibodies

OBJECTIVE

Anti-RNA polymerase I/III (anti-RNAP I/III) antibodies are clinically useful markers of scleroderma, and their presence is associated with diffuse skin disease and an increased risk of cardiac and kidney involvement. Although RNAP I antibodies localize to the nucleolus, nucleolar staining by many anti-RNAP antibody-positive sera is not always observed. Nucleolar staining by anti-RNAP antibody-positive sera was examined by double staining with antifibrillarin antibodies to evaluate whether nucleolar staining can be used as a screening test for anti-RNAP I/III antibodies. In addition, the relationships between nucleolar staining and levels of anti-RNAP III antibodies were examined by enzyme-linked immunosorbent assay (ELISA) and immunoprecipitation (IP) assay.

METHODS

Sera were tested using immunofluorescent antinuclear antibodies on HEp-2 cell slides, by anti-RNAP III ELISA, and by IP assay using (35)S-labeled K562 cell extract. Nucleolar staining by anti-RNAP antibody IP-positive sera was confirmed by double staining using antifibrillarin monoclonal antibodies. The levels of anti-RNAP III antibodies were quantitated by ELISA and by IP assay using a serially diluted reference serum as a standard, and their relationship was analyzed.

RESULTS

All 18 anti-RNAP I/III antibody-positive sera showed nuclear speckled patterns, but nucleolar staining was readily noticeable in only 44% of the sera. A positive correlation was found between ELISA and IP units for anti-RNAP III antibodies. The levels of anti-RNAP III antibodies and anti-RNAP I antibodies correlated well, with the exception of a few sera. Levels of anti-RNAP III antibodies were low in sera with nucleolar staining, whereas several sera with high levels of anti-RNAP I antibodies clearly showed nucleolar staining.

CONCLUSION

Although some sera positive for anti-RNAP I/III antibodies clearly stain nucleoli, nucleolar staining is inconsistent and cannot be used to screen for anti-RNAP I/III antibodies.

Role of non-protein amino acid L-canavanine in autoimmunity

Association of SLE and alfalfa was first reported in a volunteer who developed lupus-like autoimmunity while ingesting alfalfa seed for a hypercholesterolemia study. This was corroborated with studies in monkeys fed with alfalfa sprout that developed SLE. Re-challenge with L-canavanine relapsed the disease. Arginine homologue L-canavanine, present in alfalfa, was suspected as a cause. L-canavanine can be charged by arginyl tRNA synthetase to replace L-arginine during protein synthesis. Aberrant canavanyl proteins have disrupted structure and functions. Induction or exacerbation of SLE by alfalfa tablets reported in a few cases remains controversial. Epidemiological studies on the relationship between alfalfa and SLE are sparse. In mice, NZB/W F1, NZB, and DBA/2 mice fed with L-canavanine show exacerbation/triggering of the SLE, however, BALB/c studies were negative. L-canavanine incorporation may be more efficient in the presence of inflammation or other conditions that can cause arginine deficiency. The L-canavanine induced apoptotic cells can be phagocytosed and a source of autoantigens processed by endosomal proteases. Endogenous canavanyl proteins are ubiquitinated and processed via proteasome. Incorporation of L-canavanine into proteasome or endosome can also cause disruption of antigen processing. Alfalfa/L-canavanine-induced lupus will be an interesting model of autoimmunity induced by the modification of self-proteins at the translational level.

Regional migratory osteoporosis: a review illustrated by five cases

Regional migratory osteoporosis is an uncommon self-limiting disease characterized by an arthralgia which migrates between the weight-bearing joints of the lower limb. The radiological features of the disease obtained by conventional radiography, CT, MRI and radionuclide scintigraphy are illustrated by means of five case reports. These range from the most common presentation of sequential, proximal to distal spread in the lower limb to the rare intra-articular form, and disease involving the axial skeleton is also recognized. Clinical and radiographical features often overlap with those of diseases such as transient osteoporosis of the hip and transient bone marrow oedema syndrome, which is reflected in confusing terminology. Histological sampling is usually unnecessary; the radiological features are characteristic and the histological findings are not specific. Regional migratory osteoporosis is associated with systemic osteoporosis. This association is probably under-recognized, and has implications for the pathophysiology of the disease and for treatment.

Walking and running inter-limb asymmetry for Paralympic trans-femoral amputees, a biomechanical analysis

The aim of this project was to further the research and understanding of the trans-femoral amputee's ability to walk and run by comparing the changes in walking and running inter-limb asymmetry. An objective biomechanical analysis was conducted on four male transfemoral amputees, all members of the Australian Paralympic training squad for the 1996 Atlanta Paralympic Games. The data was collected in the biomechanics laboratories at Queensland University of Technology and the Australian Institute of Sport. The main outcomes measure a synchronised 3D kinematic (200 Hz), kinetic (600 Hz) and temporal analysis of walking at self-selected (1.1-1.3 m/s), and at maximal running speed (2.5-4.3 m/s). The walking and running biomechanical data was summarised into 27 indices of symmetry. The results showed that for all subjects the inter-limb asymmetry was significantly different at running speed, when compared to the walking speed. Using indices of symmetry 79% of the kinematic, 67% of the kinetic, and 67% of the temporal measurements identified better inter-limb asymmetry when the subjects walked, compared to running. This study objectively identified that when Paralympic level amputees ran on their standard running prosthesis, the inter-limb asymmetry was exacerbated.

Optimising the trans-femoral prosthetic alignment for running, by lowering the knee joint

For amputees to perform an everyday task, or to participate in physical exercise, it is crucial that they have an appropriately designed functional prosthesis. The aim of this study was to investigate the optimal trans-femoral prosthetic alignment configuration for running. A case study design was implemented as the method to collect data on four male Paralympic level trans-femoral amputee runners. In total 28 synchronised 3D kinematic, kinetic, and temporal biomechanical measures were analysed. A new prosthetic alignment, in which the prosthetic knee axis was lowered longitudinally (moved distally), was evaluated for running. The performance of the symmetry indices and running time for a total of three new modified alignments were compared to the standard prosthetic alignment. The interlimb asymmetry was found to improve when the subjects ran on the modified prosthetic alignment, and most importantly a one way ANOVA found a statistically significant increase in running velocity. This study identified that for all four subjects, who used the same prosthetic components, lowering the prosthetic knee joint centre improved their interlimb symmetry, and subsequently their running velocity by an average of 26%.

Treatment of sialorrhea with glycopyrrolate: A double-blind, dose-ranging study

OBJECTIVE

To determine the safety and efficacy of glycopyrrolate in the treatment of developmentally disabled children with sialorrhea.

DESIGN

Placebo-controlled, double-blind, crossover dose-ranging study.

SETTING

Outpatient facilities in 2 pediatric hospitals.

PATIENTS

Thirty-nine children with both developmental disabilities and excessive and bothersome sialorrhea.

MAIN OUTCOME MEASURES

Parent and investigator evaluation of change in sialorrhea and adverse effects.

RESULTS

Glycopyrrolate in doses of 0.10 mg/kg per dose is effective at controlling sialorrhea. Even at low doses, 20% of children may exhibit adverse effects severe enough to require discontinuation.

CONCLUSIONS

Glycopyrrolate is effective in the control of excessive sialorrhea in children with developmental disabilities. Approximately 20% of children given glycopyrrolate may experience substantial adverse effects, enough to require discontinuation of medication. Arch Pediatr Adolesc Med. 2000;154:1214-1218.

Caries prediction and indicators using a pediatric risk assessment teaching tool

The goals of this study were to determine both predictability and risk indicators in a young pediatric population seen in a dental school clinic using a Caries Risk Assessment teaching tool. Assigned risk categories and factors for 140 patients were analyzed for relationships with future caries development using Logistic Regression (p < 0.01) and Chi-square analysis (p < 0.05). Among the group developing caries, variables and disease were analyzed using ANOVA Independent Samples Test (p < 0.05). Assigned-risk categories were significantly predictive with odds ratios (OR) of Moderate- and High-risk developing new caries being 5.41 and 28.64 respectively when compared with Low-risk. Significant risk indicators were diet, oral hygiene and the presence of caries and decalcifications. The risk assessment tool used in this study predicted future caries development. Through this method of assessment, caries risk indicators in the population studied were determined to be diet, oral hygiene and past caries experience.

Metaplastic carcinoma of the breast arising within complex sclerosing lesion: a report of five cases

AIMS

This study presents a series of five cases in which metaplastic carcinoma, predominantly low-grade adenosquamous carcinoma, of the breast is seen arising within a background of a complex sclerosing lesion. This association has been recognized previously but has not been documented in detail. This study describes the characteristics of the components present in each case and discusses the existing literature. This observation adds further evidence to support an association between some types of invasive breast carcinoma and sclerosing lesions of the breast.

METHODS AND RESULTS

Four of these cases were received as referral cases for opinion. The fifth was received as part of the routine surgical workload within our own institution. Two patients presented following mammographic screening and three symptomatically; their mean age was 62 years (range 49-68). The mean lesion size was 16 mm (range 7-24). All five lesions showed features of a complex sclerosing lesion/radial scar in the form of central sclerosis with elastosis and radiating benign entrapped tubules. One had associated benign papillary structures and two had focal benign squamous metaplasia. Four cases showed coexisting but distinct areas of low-grade adenosquamous carcinoma with glandular and squamous epithelial differentiation in a spindle cell background. One case had associated undifferentiated spindle cell carcinoma. Detailed immunophenotypic characteristics of two cases are presented.

CONCLUSIONS

This series illustrates a postulated but previously unconfirmed association between an unusual form of metaplastic breast carcinoma (adenosquamous carcinoma) and complex sclerosing lesions. The mechanisms of induction of breast carcinoma are poorly understood but these observations further emphasize the potential for sclerosing lesion of the breast to be associated with, and possibly give rise to, invasive carcinoma of different types. The precise nature of the interaction between the pathological processes remains unclear.

Patient motivation

This paper addresses the important issue of patient motivation. Research indicates that non-compliance is a major problem for healthcare professionals, with between a third and a half of all patients failing to comply with recommended healthcare instructions. The paper outlines some of the misconceptions associated with motivation and discusses six factors, together with some brief additional factors, which it is hoped will contribute to a deeper understanding of the subject and the improved dental health of patients.

Investigating the relationship between economic status and HIV risk

Although anecdotal information suggests that there is a relationship between socioeconomic status and HIV risk, there have been few investigations of that possible relationship. Understanding that relationship can have important implications for designing and implementing prevention programs. This study investigated the relationship between indicators of socioeconomic status and HIV prevalence in Massachusetts using seroprevalence data from publicly funded test sites. HIV seroprevalence was found to differ depending on demographic groups and the health care insurance/provider. Those who had no insurance or were Medicaid recipients had higher rates of HIV infection. Homeless individuals were also at higher risk. Further, low-income ZIP codes in Massachusetts were four times more likely to have high seroprevalence rates among residents voluntarily testing for HIV. Thus, HIV seroprevalence appears to be associated with socioeconomic status in this group of voluntarily tested individuals.

Sex, drugs and HIV counseling and testing: a prospective study of behavior-change among methadone-maintenance clients in New England

OBJECTIVES

To determine whether changes in injecting drug use and sexual behavior over a 12-month follow-up are associated with HIV counseling and testing (C and T) of injecting drug users in methadone maintenance treatment programs (MMTP) in Massachusetts and Connecticut.

METHODS

Clients were invited to participate in a longitudinal study involving five interviews. Data were also obtained by ethnographers and from clinical records. Behavioral outcomes of interest were number of drug injections, sharing of unclean 'works' (injecting equipment), number of unprotected sex partners, and number of unprotected sexual episodes. Data analyses included multiple regression, odds ratios, and quantitative analysis of text-based data.

RESULTS

Subjects reported reductions in both injecting drug use and sexual behavior Primary associations with reduced injecting drug use were remaining in the MMTP and attending HIV-positive support groups. A reduction in high-risk sexual behavior was associated with an HIV-positive test result and duration of HIV counseling in the MMTP. Increase in drug injecting use was associated with an HIV-positive test result. Inconsistent condom use was associated with enrollment in the MMTP where condoms were available only upon request and abstinence and monogamy between uninfected partners were promoted.

CONCLUSIONS

Injecting drug users who self-select to participate in MMTP and HIV C and T, two public health HIV-prevention interventions, reduce their HIV-risk behaviors. Clients should be encouraged to remain in MMTP and HIV-infected clients should attend support groups for HIV-positive persons. MMTP staff should promote a variety of safer sex behaviors and provide condoms without request.

Retention in methadone maintenance treatment programs, Connecticut and Massachusetts, 1990-1993

The goal of this study was to identify factors associated with six- and 12-month retention in methadone maintenance treatment programs (MMTPs) in Massachusetts and Connecticut. Data was obtained from 674 participants, clinic records, and clinic staff. Ethnographic and logistic regression analyses were conducted. Overall, 69% and 48% of the clients remained in treatment at six months and 12 months, respectively. The MMTPs were categorized as either a 12-Step, case management, or primary care model. Factors independently associated with retention in treatment at six months were each one-year increase in age of client (OR 1.05), injecting at three months (OR 0.47), and enrollment in the primary care model (OR 2.10). The same factors were associated with 12-month retention in treatment. To retain clients in MMTPs-which should, in turn, help reduce drug use and prevent HIV transmission among IDUs-younger IDUs and clients still injecting at three months after entering drug treatment may need additional services from the staff, or alternative treatment regimens. MMTP directors should consider differences between these programs and, if appropriate, make changes to increase retention in treatment.

Cytokine regulation of HIV replication induced by dendritic cell-CD4-positive T cell interactions

It has been established that human immunodeficiency virus (HIV) replication occurs throughout the course of disease in the lymphoid tissue. We have developed a model system to study the effect of cytokines and other agents on HIV replication using cocultures of DCs and T cells that reflect the cell-to-cell interactions that occur in the microenvironment of lymphoid tissue. Dendritic cells from peripheral blood, when pulsed with small amounts of HIV, induce infection in autologous, unstimulated CD4-positive T cells. Using this system, cytokines, anti-cytokine antibodies, and inhibitors of cellular activation were added to cultures and the effects on cellular proliferation and activation and HIV production were measured. Cytokines that increased T cell proliferation, such as IL-2 and IL-4, enhanced HIV replication, while the effect of IL-12 was more complex. HIV production was inhibited by blocking endogenously produced IL-2, as well as by adding IL-10, which blocks IL-2 secretion, antigen-presenting cell function, and T cell activation. Proinflammatory cytokines induced modest enhancement of viral replication in cocultures of HIV-pulsed DCs and CD4-positive T cells. Thus, using a model of HIV replication that more closely mimics the in vivo microenvironment of lymphoid tissue may allow a better analysis of the effect of cytokines and cytokine networks, as well as agents that modify immune activation on HIV replication.