Stress avulsion of the tibial tuberosity after tension band wiring of a patellar fracture: a case report

INTRODUCTION: To the best of our knowledge there is no other report of an elderly patient who was surgically treated for a patellar fracture with tension band wiring and who subsequently suffered from an avulsion fracture of the tibial tuberosity. The combination of a patellar fracture and avulsion of the patellar ligament has only been described as complication after bone-patellar tendon-bone anterior cruciate ligament reconstructions. However, due to demographic changes and more elderly patients treated this injury may become more frequent in future. CASE PRESENTATION: We present the case of an 81 year old female who sustained an oblique patellar fracture after a direct contact injury of the left knee when falling on ice. Consequently the patellar fracture was openly reduced and stabilized with tension band wiring. The follow-up was uneventful till three months after surgery when the patient noticed a spontaneous avulsion fracture of the tibial tuberosity (Ogden type 3). The tibial tuberosity fragment was reattached with two non-resorbable sutures looped around two modified AO cortical 3.5 mm long neck screws. Intraoperatively multiple bone cysts were seen. Biopsies were not taken to prevent further fragmentation of the tibial tuberosity. The patient was followed up with anteroposterior and lateral full weight bearing radiographs and clinical assessment at 6, 12 weeks and 6 months after surgery. Recovery was completely pain free with full satisfaction. CONCLUSION: In conclusion in elderly patients with a patella fracture a possible associated but not obvious fracture of the tibial tuberosity should be ruled out and the postoperative rehabilitation protocol after tension band wiring of the patella might have to be individually adjusted to bone quality and course of the fracture

The Role of Indoleamine 2,3-Dioxygenase in LP-BPM5 Murine Retroviral Disease Progression

Indoleamine 2,3-dioxygenase (IDO) is an immunomodulatory intracellular enzyme involved in tryptophan degradation. IDO is induced during cancer and microbial infections by cytokines, ligation of co-stimulatory molecules and/or activation of pattern recognition receptors, ultimately leading to modulation of the immune response. LP-BM5 murine retroviral infection induces murine AIDS (MAIDS), which is characterized by profound and broad immunosuppression of T- and B-cell responses. Our lab has previously described multiple mechanisms regulating the development of immunodeficiency of LP-BM5-induced disease, including Programmed Death 1 (PD-1), IL-10, and T-regulatory (Treg) cells. Immunosuppressive roles of IDO have been demonstrated in other retroviral models, suggesting a possible role for IDO during LP-BM5-induced retroviral disease progression and/or development of viral load

Non-operative management of posterior tibialis tendon dysfunction: design of a randomized clinical trial [NCT00279630]

BACKGROUND: Posterior tibialis tendon dysfunction (PTTD) is a common cause of foot pain and dysfunction in adults. Clinical observations strongly suggest that the condition is progressive. There are currently no controlled studies evaluating the effectiveness of exercise, orthoses, or orthoses and exercise on Stage I or IIA PTTD. Our study will explore the effectiveness of an eccentric versus concentric strengthening intervention to results obtained with the use of orthoses alone. Findings from this study will guide the development of more efficacious PTTD intervention programs and contribute to enhanced function and quality of life in persons with posterior tibialis tendon dysfunction. METHODS/DESIGN: This paper presents the rationale and design for a randomized clinical trial evaluating the effectiveness of a treatment regime for the non-operative management of Stage I or IIA PTTD. DISCUSSION: We have presented the rationale and design for an RCT evaluating the effectiveness of a treatment regimen for the non-operative management of Stage I or IIA PTTD. The results of this trial will be presented as soon as they are available

Reconstitution of huPBL-NSG Mice with Donor-Matched Dendritic Cells Enables Antigen-Specific T-cell Activation

Humanized mouse models provide a unique opportunity to study human immune cells in vivo, but traditional models have been limited to the evaluation of non-specific T-cell interactions due to the absence of antigen-presenting cells. In this study, immunodeficient NOD/SCID/IL2r-γnull (NSG) mice were engrafted with human peripheral blood lymphocytes alone or in combination with donor-matched monocyte-derived dendritic cells (DC) to determine whether antigen-specific T-cell activation could be reconstituted. Over a period of 3 weeks, transferred peripheral blood lymphocytes reconstituted the spleen and peripheral blood of recipient mice with predominantly human CD45-positive lymphocytes. Animals exhibited a relatively normal CD4/CD8 ratio (average 1.63:1) as well as reconstitution of CD3/CD56 (averaging 17.8%) and CD20 subsets (averaging 4.0%). Animals reconstituted with donor-matched CD11c+ DC also demonstrated a CD11c+ population within their spleen, representing 0.27% to 0.43% of the recovered human cells with concurrent expression of HLA-DR, CD40, and CD86. When immunized with adenovirus, either as free replication-incompetent vector (AdV) or as vector-transduced DC (DC/AdV), there was activation and expansion of AdV-specific T-cells, an increase in Th1 cytokines in serum, and skewing of T-cells toward an effector/memory phenotype. T-cells recovered from animals challenged with AdV in vivo proliferated and secreted a Th1-profile of cytokines in response to DC/AdV challenge in vitro. Our results suggest that engrafting NSG mice with a combination of lymphocytes and donor-matched DC can reconstitute antigen responsiveness and allow the in vivo assessment of human immune response to viruses, vaccines, and other immune challenges

Resistance to the CCR5 Inhibitor 5P12-RANTES Requires a Difficult Evolution from CCR5 to CXCR4 Coreceptor Use

Viral resistance to small molecule allosteric inhibitors of CCR5 is well documented, and involves either selection of preexisting CXCR4-using HIV-1 variants or envelope sequence evolution to use inhibitor-bound CCR5 for entry. Resistance to macromolecular CCR5 inhibitors has been more difficult to demonstrate, although selection of CXCR4-using variants might be expected. We have compared the in vitro selection of HIV-1 CC1/85 variants resistant to either the small molecule inhibitor maraviroc (MVC) or the macromolecular inhibitor 5P12-RANTES. High level resistance to MVC was conferred by the same envelope mutations as previously reported after 16–18 weeks of selection by increasing levels of MVC. The MVC-resistant mutants were fully sensitive to inhibition by 5P12-RANTES. By contrast, only transient and low level resistance to 5P12-RANTES was achieved in three sequential selection experiments, and each resulted in a subsequent collapse of virus replication. A fourth round of selection by 5P12-RANTES led, after 36 weeks, to a “resistant” variant that had switched from CCR5 to CXCR4 as a coreceptor. Envelope sequences diverged by 3.8% during selection of the 5P12-RANTES resistant, CXCR4-using variants, with unique and critical substitutions in the V3 region. A subset of viruses recovered from control cultures after 44 weeks of passage in the absence of inhibitors also evolved to use CXCR4, although with fewer and different envelope mutations. Control cultures contained both viruses that evolved to use CXCR4 by deleting four amino acids in V3, and others that maintained entry via CCR5. These results suggest that coreceptor switching may be the only route to resistance for compounds like 5P12-RANTES. This pathway requires more mutations and encounters more fitness obstacles than development of resistance to MVC, confirming the clinical observations that resistance to small molecule CCR5 inhibitors very rarely involves coreceptor switching

Development and Validity of the Rating-of-Fatigue Scale

Objective: The purpose of these experiments was to develop a rating-of-fatigue (ROF) scale capable of tracking the intensity of perceived fatigue in a variety of contexts. Methods: Four experiments were carried out. The first provided the evidential basis for the construction of the ROF scale. The second tested the face validity of the ROF, and the third tested the convergent and divergent validity of the ROF scale during ramped cycling to exhaustion and 30 min of resting recovery. The final experiment tested the convergent validity of the ROF scale with time of day and physical activity (accelerometer counts) across a whole week. Results: Modal selections of descriptions and diagrams at different levels of exertion and recovery were found during Experiment 1 upon which the ROF scale was constructed and finalised. In Experiment 2, a high level of face validity was indicated, in that ROF was reported to represent fatigue rather than exertion. Descriptor and diagrammatic elements of ROF reportedly added to the coherence and ease of use of the scale. In Experiment 3, high convergence between ROF and various physiological measures were found during exercise and recovery (heart rate, blood lactate concentration, oxygen uptake, carbon dioxide production, respiratory exchange ratio and ventilation rate were all P < 0.001). During ramped cycling to exhaustion ROF and RPE did correspond (P < 0.0001) but not during recovery, demonstrating discriminant validity. Experiment 4 found ROF to correspond with waking time during each day (Mon–Sun all P < 0.0001) and with physical activity (accelerometer count) (Mon–Sun all P < 0.001). Conclusions: The ROF scale has good face validity and high levels of convergent validity during ramped cycling to exhaustion, resting recovery and daily living activities. The ROF scale has both theoretical and applied potential in understanding changes in fatigue in a variety of contexts

Clinical practice: Swallowing problems in cerebral palsy

Cerebral palsy (CP) is the most common physical disability in early childhood. The worldwide prevalence of CP is approximately 2–2.5 per 1,000 live births. It has been clinically defined as a group of motor, cognitive, and perceptive impairments secondary to a non-progressive defect or lesion of the developing brain. Children with CP can have swallowing problems with severe drooling as one of the consequences. Malnutrition and recurrent aspiration pneumonia can increase the risk of morbidity and mortality. Early attention should be given to dysphagia and excessive drooling and their substantial contribution to the burden of a child with CP and his/her family. This review displays the important functional and anatomical issues related to swallowing problems in children with CP based on relevant literature and expert opinion. Furthermore, based on our experience, we describe a plan for approach of investigation and treatment of swallowing problems in cerebral palsy

Detecting functional magnetic resonance imaging activation in white matter: Interhemispheric transfer across the corpus callosum

<p>Abstract</p> <p>Background</p> <p>It is generally believed that activation in functional magnetic resonance imaging (fMRI) is restricted to gray matter. Despite this, a number of studies have reported white matter activation, particularly when the corpus callosum is targeted using interhemispheric transfer tasks. These findings suggest that fMRI signals may not be neatly confined to gray matter tissue. In the current experiment, 4 T fMRI was employed to evaluate whether it is possible to detect white matter activation. We used an interhemispheric transfer task modelled after neurological studies of callosal disconnection. It was hypothesized that white matter activation could be detected using fMRI.</p> <p>Results</p> <p>Both group and individual data were considered. At liberal statistical thresholds (p < 0.005, uncorrected), group level activation was detected in the isthmus of the corpus callosum. This region connects the superior parietal cortices, which have been implicated previously in interhemispheric transfer. At the individual level, five of the 24 subjects (21%) had activation clusters that were located primarily within the corpus callosum. Consistent with the group results, the clusters of all five subjects were located in posterior callosal regions. The signal time courses for these clusters were comparable to those observed for task related gray matter activation.</p> <p>Conclusion</p> <p>The findings support the idea that, despite the inherent challenges, fMRI activation can be detected in the corpus callosum at the individual level. Future work is needed to determine whether the detection of this activation can be improved by utilizing higher spatial resolution, optimizing acquisition parameters, and analyzing the data with tissue specific models of the hemodynamic response. The ability to detect white matter fMRI activation expands the scope of basic and clinical brain mapping research, and provides a new approach for understanding brain connectivity.</p

Situational awareness, relational coordination and integrated care delivery to hospitalized elderly in the Netherlands: A comparison between hospitals

__Abstract__ Background: It is known that interprofessional collaboration is crucial for integrated care delivery, yet we are still unclear about the underlying mechanisms explaining effectiveness of integrated care delivery to older patients. In addition, we lack research comparing integrated care delivery between hospitals. Therefore, this study aims to (i) provide insight into the underlying components 'relational coordination' and 'situational awareness' of integrated care delivery and the role of team and organizational context in integrated care delivery; and (ii) compare situational awareness, relational coordination, and integrated care delivery of different hospitals in the Netherlands. Methods. This cross-sectional study took place in 2012 among professionals from three different hospitals involved in the delivery of care to older patients. A total of 215 professionals filled in the questionnaire (42% response rate).Descriptive statistics and paired-sample t-tests were used to investigate the level of situational awareness, relational coordination, and integrated care delivery in the three different hospitals. Correlation and multilevel analyses were used to investigate the relationship between background characteristics, team context, organizational context, situational awareness, relational coordination and integrated care delivery. Results: No differences in background characteristics, team context, organizational context, situational awareness, relational coordination and integrated care delivery were found among the three hospitals. Correlational analysis revealed that situational awareness (r = 0.30; p < 0.01), relational coordination (r = 0.17; p < 0.05), team climate (r = 0.29; p < 0.01), formal internal communication (r = 0.46; p < 0.01), and informal internal communication (r = 0.36; p < 0.01) were positively associated with integrated care delivery. Stepwise multilevel analyses showed that formal internal communication (p < 0.001) and situational awareness (p < 0.01) were associated with integrated care delivery. Team climate was not significantly associated with integrated care delivery when situational awareness and relational coordination were included in the equation. Thus situational awareness acted as mediator between team climate and integrated care delivery among professionals delivering care to older hospitalized patients. Conclusions: The results of this study show the importance of formal internal communication and situational awareness for quality of care delivery to hospitalized older patients

Nitrate Reduction Functional Genes and Nitrate Reduction Potentials Persist in Deeper Estuarine Sediments. Why?

Denitrification and dissimilatory nitrate reduction to ammonium (DNRA) are processes occurring simultaneously under oxygen-limited or anaerobic conditions, where both compete for nitrate and organic carbon. Despite their ecological importance, there has been little investigation of how denitrification and DNRA potentials and related functional genes vary vertically with sediment depth. Nitrate reduction potentials measured in sediment depth profiles along the Colne estuary were in the upper range of nitrate reduction rates reported from other sediments and showed the existence of strong decreasing trends both with increasing depth and along the estuary. Denitrification potential decreased along the estuary, decreasing more rapidly with depth towards the estuary mouth. In contrast, DNRA potential increased along the estuary. Significant decreases in copy numbers of 16S rRNA and nitrate reducing genes were observed along the estuary and from surface to deeper sediments. Both metabolic potentials and functional genes persisted at sediment depths where porewater nitrate was absent. Transport of nitrate by bioturbation, based on macrofauna distributions, could only account for the upper 10 cm depth of sediment. A several fold higher combined freeze-lysable KCl-extractable nitrate pool compared to porewater nitrate was detected. We hypothesised that his could be attributed to intracellular nitrate pools from nitrate accumulating microorganisms like Thioploca or Beggiatoa. However, pyrosequencing analysis did not detect any such organisms, leaving other bacteria, microbenthic algae, or foraminiferans which have also been shown to accumulate nitrate, as possible candidates. The importance and bioavailability of a KCl-extractable nitrate sediment pool remains to be tested. The significant variation in the vertical pattern and abundance of the various nitrate reducing genes phylotypes reasonably suggests differences in their activity throughout the sediment column. This raises interesting questions as to what the alternative metabolic roles for the various nitrate reductases could be, analogous to the alternative metabolic roles found for nitrite reductases