Erlotinib suppresses tumorigenesis in a mouse model of colitis-associated cancer.

Colitis-associated cancer (CAC) in inflammatory bowel diseases exhibits more aggressive behavior than sporadic colorectal cancer; however, the molecular mechanisms remain unclear. No definitive preventative agent against CAC is currently established in the clinical setting. We investigated the molecular mechanisms of CAC in the azoxymethane/dextran sulfate sodium (AOM/DSS) mouse model and assessed the antitumor efficacy of erlotinib, a small molecule inhibitor of the epidermal growth factor receptor (EGFR). Erlotinib premixed with AIN-93 G diet at 70 or 140 parts per million (ppm) inhibited tumor multiplicity significantly by 96%, with ∼60% of the treated mice exhibiting zero polyps at 12 weeks. Bulk RNA-sequencing revealed more than a thousand significant gene alterations in the colons of AOM/DSS-treated mice, with KEGG enrichment analysis highlighting 46 signaling pathways in CAC development. Erlotinib altered several signaling pathways and rescued 40 key genes dysregulated in CAC, including those involved in the Hippo and Wnt signaling. These findings suggest that the clinically-used antitumor agent erlotinib might be repurposed for suppression of CAC, and that further studies are warranted on the crosstalk between dysregulated Wnt and EGFR signaling in the corresponding patient population.

MicroRNAs in Inflammatory Bowel Disease and Its Complications.

Inflammatory bowel disease (IBD), classified primarily between Crohn's disease and ulcerative colitis, is a collection of chronic gastrointestinal inflammatory conditions that cause multiple complications because of systemic alterations in the immune response. One major player is microRNA (miRNA), which is found to be associated with multiple pathways in mediating inflammation, especially those of a chronic nature in IBD, as well as irritable bowel syndrome. Although there have been studies linking miRNA alterations in IBD, even differentiating Crohn's disease and ulcerative colitis, this review focuses mainly on how miRNAs cause and mechanistically influence the pathologic complications of IBD. In addition to its role in the well-known progression towards colorectal cancer, we also emphasize how miRNA manifests the many extraintestinal complications in IBD such as cardiovascular diseases; neuropsychiatric conditions such as depression and anxiety disorders; and others, including various musculoskeletal, dermatologic, ocular, and hepatobiliary complications. We conclude through a description of its potential use in bettering diagnostics and the future treatment of IBD and its systemic symptoms.

Exosomal miR-29b of Gut Origin in Patients With Ulcerative Colitis Suppresses Heart Brain-Derived Neurotrophic Factor.

Background and Aims: While the interplay between heart and gut in inflammatory bowel disease (IBD) has previously been noted, how the inflamed gut impairs heart function remain elusive. We hypothesized that exosomal miRNAs of gut origin induce cardiac remodeling in IBD. Our aim was to identify plasma exosomal miRNAs that not only are of diagnostic value but also contribute to cardiac remodeling in patients with ulcerative colitis (UC). Methods: Plasma exosomes were isolated from UC patients and healthy control subjects and exosomal miRNAs were profiled by next-generation sequencing. Exosomal miR-29b levels in CCD841 CoN colon epithelial cells were detected by RT-qPCR. Exosomes packaged with miR-29b were incubated with H9c2 cells or administered to live mice. Results: The plasma exosomal miRNA profiles of the UC patients were significantly different from that of the controls and 20 miRNAs including miR-29b were differentially expressed. In CCD841 CoN cells, TNFα, IL-1ß, and H2O2 significantly elevated miR-29b in both the cells and their secreted exosomes (p < 0.01), suggesting that intestinal epithelium secrets exosomes rich in miR-29b in IBD. In H9c2 myoblast cells, miR-29b modulated multiple genes including brain-derived neurotrophic factor (BDNF). Epithelial cell-derived exosomes packaged with miR-29b also attenuated BDNF and increased cleaved caspase 3, suggestive of apoptosis. Furthermore, tail vein injection of engineered exosomes with high levels of miR-29b suppressed BDNF and augmented cleaved caspase 3 in the heart of adult mouse (p < 0.01). Conclusion: Plasma exosomal miRNA profile could be a novel diagnostic approach for IBD. Excessive plasma exosomal miR-29b suppresses critical proteins like BDNF in IBD, leading to cardiac impairment.

S-nitrosothiols signaling in cystic fibrosis airways.

S-nitrosothiols (SNOs) are small naturally occurring thiol and nitric oxide adducts that participate in many cell signaling pathways in living organisms. SNOs receive widespread attention in cell biology, biochemistry and chemistry because they can donate nitric oxide and/or nitrosonium ions in S-nitrosylation reactions, which are comparable to phosphorylation, acetylation, glutathionylation, and palmitoylation reactions. SNOs have advantageous effects in respiratory diseases and other systems in the body. S-nitrosylation signaling is a metabolically regulated physiological process that leads to specific post-translational protein modifications. S-nitrosylation signaling is faulty in cystic fibrosis (CF) and many other lung diseases. CF is an inherited, lethal autosomal recessive multisystem disease resulting from mutations in the gene encoding the CF transmembrane conductance regulatory (CFTR) protein. F508del CFTR is the most common mutation associated with CF, which results in CFTR misfolding because a phenylalanine is deleted from the primary structure of CFTR. The majority of wild-type CFTR and almost all F508del is degraded before reaching the cell surface. Ultimately, CF researchers have been looking to correct the mutated CFTR protein in the CF patients. Remarkably, researchers have found that SNOs levels are low in the CF lower airway compared to non-CF patients. We have been interested in determining whether SNOs increase CFTR maturation through S-nitrosylation. Maturation of both wild type and mutant F508del CFTR increases SNOs, which up-regulate CFTR maturation. In this review, we summarized our current knowledge of S-nitrosothiols signaling in cystic fibrosis airways.

Antimicrobial properties of tomato leaves, stems, and fruit and their relationship to chemical composition.

BACKGROUND: We previously reported that the tomato glycoalkaloid tomatine inhibited the growth of Trichomonas vaginalis strain G3, Tritrichomonas foetus strain D1, and Tritrichomonas foetus-like strain C1 that cause disease in humans and farm and domesticated animals. The increasing prevalence of antibiotic resistance requires development of new tools to enhance or replace medicinal antibiotics. METHODS: Wild tomato plants were harvested and divided into leaves, stems, and fruit of different colors: green, yellow, and red. Samples were freeze dried and ground with a handheld mill. The resulting powders were evaluated for their potential anti-microbial effects on protozoan parasites, bacteria, and fungi. A concentration of 0.02% (w/v) was used for the inhibition of protozoan parasites. A high concentration of 10% (w/v) solution was tested for bacteria and fungi as an initial screen to evaluate potential anti-microbial activity and results using this high concentration limits its clinical relevance. RESULTS: Natural powders derived from various parts of tomato plants were all effective in inhibiting the growth of the three trichomonads to varying degrees. Test samples from leaves, stems, and immature 'green' tomato peels and fruit, all containing tomatine, were more effective as an inhibitor of the D1 strain than those prepared from yellow and red tomato peels which lack tomatine. Chlorogenic acid and quercetin glycosides were present in all parts of the plant and fruit, while caffeic acid was only found in the fruit peels. Any correlation between plant components and inhibition of the G3 and C1 strains was not apparent, although all the powders were variably effective. Tomato leaf was the most effective powder in all strains, and was also the highest in tomatine. S. enterica showed a minor susceptibility while B. cereus and C. albicans fungi both showed a significant growth inhibition with some of the test powders. The powders inhibited growth of the pathogens without affecting beneficial lactobacilli found in the normal flora of the vagina. CONCLUSIONS: The results suggest that powders prepared from tomato leaves, stems, and green tomato peels and to a lesser extent from peels from yellow and red tomatoes offer potential multiple health benefits against infections caused by pathogenic protozoa, bacteria, and fungi, without affecting beneficial lactobacilli that also reside in the normal flora of the vagina.

Overview of the Therapeutic Potential of Aptamers Targeting Coagulation Factors.

Aptamers are single-stranded DNA or RNA sequences that bind target molecules with high specificity and affinity. Aptamers exhibit several notable advantages over protein-based therapeutics. Aptamers are non-immunogenic, easier to synthesize and modify, and can bind targets with greater affinity. Due to these benefits, aptamers are considered a promising therapeutic candidate to treat various conditions, including hematological disorders and cancer. An active area of research involves developing aptamers to target blood coagulation factors. These aptamers have the potential to treat cardiovascular diseases, blood disorders, and cancers. Although no aptamers targeting blood coagulation factors have been approved for clinical use, several aptamers have been evaluated in clinical trials and many more have demonstrated encouraging preclinical results. This review summarized our knowledge of the aptamers targeting proteins involved in coagulation, anticoagulation, fibrinolysis, their extensive applications as therapeutics and diagnostics tools, and the challenges they face for advancing to clinical use.

Anti-Parasitic Activity of Cherry Tomato Peel Powders.

Trichomoniasis in humans, caused by the protozoal parasite Trichomonas vaginalis, is the most common non-viral sexually transmitted disease, while Tritrichomonas foetus causes trichomonosis, an infection of the gastrointestinal tract and diarrhea in farm animals and domesticated cats. As part of an effort to determine the inhibitory effects of plant-based extracts and pure compounds, seven commercially available cherry tomato varieties were hand-peeled, freeze-dried, and pounded into powders. The anti-trichomonad inhibitory activities of these peel powders at 0.02% concentration determined using an in vitro cell assay varied widely from 0.0% to 66.7% against T. vaginalis G3 (human); from 0.9% to 66.8% for T. foetus C1 (feline); and from 0.0% to 81.3% for T. foetus D1 (bovine). The organic Solanum lycopersicum var. cerasiforme (D) peels were the most active against all three trichomonads, inhibiting 52.2% (G3), 66.8% (C1), and 81.3% (D1). Additional assays showed that none of the powders inhibited the growth of foodborne pathogenic bacteria, pathogenic fungi, or non-pathogenic lactobacilli. Tomato peel and pomace powders with high content of described biologically active compounds could serve as functional food and feed additives that might help overcome adverse effects of wide-ranging diseases and complement the treatment of parasites with the anti-trichomonad drug metronidazole.

Task phase-specific involvement of the rat posterior parietal cortex in performance of the TUNL task.

The posterior parietal cortex (PPC) participates in cognitive processes including working memory (WM), sensory evidence accumulation, and perceptually guided decision making. However, surprisingly little work has used temporally precise manipulations to dissect its role in different epochs of behavior taking place over short timespans, such as WM tasks. As a result, a consistent view of the temporally precise role of the PPC in these processes has not been described. In the present study, we investigated the temporally specific role of the PPC in the Trial-Unique, Nonmatching-to-Location (TUNL) task, a touchscreen-based, visuospatial WM task that relies on the PPC. To disrupt PPC activity in a temporally precise manner, we applied mild intracranial electrical stimulation (ICES). We found that intra-PPC ICES (100 µA) significantly impaired accuracy in TUNL without significantly altering response latency. Moreover, we found that the impairment was specific to ICES applied during the delay and test phases of TUNL. Consistent with previous reports showing delay- and choice-specific neuronal activity in the PPC, the results provide evidence that the rat PPC is required for maintaining memory representations of stimuli over a delay period as well as for making successful comparisons and choices between test stimuli. In contrast, the PPC appears not to be critical for initial encoding of sample stimuli. This pattern of results may indicate that early encoding of visual stimuli is independent of the PPC or that the PPC becomes engaged only when visual stimuli are spatially complex or involve memory or decision making.

Intramedullary Nailing Versus External Fixation in the Treatment of Open Tibial Fractures in Tanzania: Results of a Randomized Clinical Trial.

BACKGROUND: Open tibial fractures are common injuries in low and middle-income countries, but there is no consensus regarding treatment with intramedullary nailing versus external fixation. The purpose of the present study was to compare the outcomes of initial treatment with intramedullary nailing or external fixation in adults with open tibial fractures. METHODS: We conducted a randomized clinical trial (RCT) at a tertiary orthopaedic center in Tanzania. Adults with acute diaphyseal open tibial fractures were randomly assigned to statically locked, hand-reamed intramedullary nailing or uniplanar external fixation. The primary outcome was death or reoperation for the treatment of deep infection, nonunion, or malalignment. Secondary outcomes included quality of life as measured with the EuroQol-5 Dimensions (EQ-5D) questionnaire, radiographic alignment, and healing as measured with the modified Radiographic Union Scale for Tibial fractures (mRUST). RESULTS: Of the 240 patients who were enrolled, 221 (92.1%) (including 111 managed with intramedullary nailing and 110 managed with external fixation) completed 1-year follow-up. There were 44 primary outcome events (with rates of 18.0% and 21.9% in the intramedullary nailing and external fixation groups, respectively) (relative risk [RR] = 0.83 [95% confidence interval (CI), 0.49 to 1.41]; p = 0.505). There was no significant difference between the groups in terms of the rate of deep infection. Intramedullary nailing was associated with a lower risk of coronal malalignment (RR = 0.11 [95% CI, 0.01 to 0.85]; p = 0.01) and sagittal malalignment (RR = 0.17 [95% CI, 0.02 to 1.35]; p = 0.065) at 1 year. The EQ-5D index favored intramedullary nailing at 6 weeks (mean difference [MD] = 0.07 [95% CI = 0.03 to 0.11]; p < 0.001), but this difference dissipated by 1 year. Radiographic healing (mRUST) favored intramedullary nailing at 6 weeks (MD = 1.2 [95% CI = 0.4 to 2.0]; p = 0.005), 12 weeks (MD = 1.0 [95% CI = 0.3 to 1.7]; p = 0.005), and 1 year (MD = 0.8 [95% CI = 0.2 to 1.5]; p = 0.013). CONCLUSIONS: To our knowledge, the present study is the first RCT assessing intramedullary nailing versus external fixation for the treatment of open tibial fractures in sub-Saharan Africa. Differences in primary events were not detected, and only coronal alignment significantly favored the use of intramedullary nailing. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Roles of the medial prefrontal cortex, mediodorsal thalamus, and their combined circuit for performance of the odor span task in rats: analysis of memory capacity and foraging behavior.

Working memory (WM), the capacity for short-term storage of small quantities of information for immediate use, is thought to depend on activity within the prefrontal cortex. Recent evidence indicates that the prefrontal neuronal activity supporting WM is driven by thalamocortical connections arising in mediodorsal thalamus (mdThal). However, the role of these connections has not been studied using olfactory stimuli leaving open the question of whether this circuit extends to all sensory modalities. Additionally, manipulations of the mdThal in olfactory memory tasks have yielded mixed results. In the present experiment, we investigated the role of connections between the rat medial prefrontal cortex (mPFC) and mdThal in the odor span task (OST) using a pharmacological contralateral disconnection technique. Inactivation of either the mPFC or mdThal alone both significantly impaired memory performance in the OST, replicating previous findings with the mPFC and confirming that the mdThal plays an essential role in intact OST performance. Contralateral disconnection of the two structures impaired OST performance in support of the idea that the OST relies on mPFC-mdThal connections, but ipsilateral control infusions also impaired performance, complicating this interpretation. We also performed a detailed analysis of rats' errors and foraging behavior and found a dissociation between mPFC and mdThal inactivation conditions. Inactivation of the mdThal and mPFC caused a significant reduction in the number of approaches rats made per odor, whereas only mdThal inactivation or mPFC-mdThal disconnection caused significant increases in choice latency. Our results confirm that the mdThal is necessary for performance of the OST and that it may critically interact with the mPFC to mediate OST performance. Additionally, we have provided evidence that the mPFC and mdThal play dissociable roles in mediating foraging behavior.

Surgical Implant Generation Network (SIGN) Fin nail versus SIGN standard intramedullary nail for distal diaphyseal femur fractures treated via retrograde approach.

INTRODUCTION: Surgical fixation of distal diaphyseal femur fractures remains a major challenge in developing countries given limited availability of fluoroscopy. The Surgical Implant Generation Network (SIGN) Standard Intramedullary Nail and SIGN Fin Nail are two modalities developed to address this challenge; the Fin Nail additionally avoids needing to place proximal interlocking screws. While efficacy of the Standard Nail has been established, outcomes following fixation with the Fin Nail are unknown. In this study, we compare outcomes of distal diaphyseal femur fractures treated with each implant. METHODS: A prospective cohort study was conducted from 2012 to 2013 at a single tertiary-referral center in Tanzania. Skeletally mature patients with distal diaphyseal femur fractures treated with either retrograde SIGN Standard Nail or Fin Nail were included. Patients followed-up at 6, 12, 26, and 52 weeks post-operatively. The primary outcome was all-cause reoperation. Secondary outcomes included infection, non-union, malalignment, quality of life (EQ-5D score), pain (VAS score), radiographic healing (RUST score), and function (pain with weight bearing, knee range of motion, and Squat and Smile score). RESULTS: 74 (85%) of 85 enrolled patients completed the minimum 1-year follow-up. There was no difference in rate of reoperation (p = 1.00), infection (p = 1.00), limb length discrepancy (p = 0.47), non-union (p = 1.00), or coronal or sagittal malalignment (p = 1.00, p = 0.55 respectively) at 1 year. There was furthermore no difference in mean EQ-5D (p = 0.82), VAS pain score (p = 0.43), RUST score (p = 0.44), maximum knee flexion (p = 0.52) and extension (p = 1.00), or Squat and Smile function (p = 1.00) between cohorts at 1 year. DISCUSSION: Outcomes associated with the SIGN Fin Nail are comparable to those associated with the SIGN Standard Intramedullary Nail at 1 year. The SIGN Fin Nail may be useful as an alternative to Standard locked IM nails for fixation of distal diaphyseal femur fractures.

Early treatment of open diaphyseal tibia fracture with intramedullary nail versus external fixator in Tanzania: Cost effectiveness analysis using preliminary data from Muhimbili Orthopaedic Institute.

INTRODUCTION: Open tibia fractures are some of the most common types of Orthopedics injuries in low- and middle-income countries (LMICs). In Tanzania, open tibia fractures are treated either conservatively by prolonged cast or surgically by external fixation (EF) or intramedullary nail (IMN) when available. The cost of treatment and amount of time patients spend away from work are major economic concerns with prolonged casting and EF. The goal of this study was to determine the cost effectiveness of IMN versus EF in the treatment of open diaphyseal tibia fractures at Muhimbili Orthopaedic Institute (Dar es Salaam, Tanzania). METHODS: This is a prospective randomized control study conducted of patients with a closeable AO/OTA 42 open diaphyseal tibia fracture. The patients underwent surgical fixation with either IMN or EF at Muhimbili Orthopaedic Institute (MOI), and were followed up at 2, 6, and 12 weeks postoperatively. A micro-costing method was used to estimate the fixed and variable costs of IMN and EF of the open diaphyseal tibial fracture. RESULTS: The mean total cost per patient was lower for the IMN group ($425.8 ± 38.4) compared to the EF group ($559.6 ± 70.5, p < 0.001), with savings of $133.80 per patient for the IMN group. The mean hospital stay was 2.72 ± 1.40 days for the IMN group and 2.44 ± 1.47 days for the EF group (p = 0.5). Quality-adjusted life years (QALYs) were 0.26 per patient for the IMN group and 0.24 in the EF group at 12 weeks (p = 0.8). Ninety-two percent of patients in the IMN group achieved fracture union versus 60% in the EF group at three months postoperatively (p = 0.03). CONCLUSION: IM nailing of a closeable open diaphyseal tibial fracture is more cost effective than EF. In addition, IM nailing has better union rates at three months compared to EF.

Thermal constraints on in vivo optogenetic manipulations.

A key assumption of optogenetics is that light only affects opsin-expressing neurons. However, illumination invariably heats tissue, and many physiological processes are temperature-sensitive. Commonly used illumination protocols increased the temperature by 0.2-2 °C and suppressed spiking in multiple brain regions. In the striatum, light delivery activated an inwardly rectifying potassium conductance and biased rotational behavior. Thus, careful consideration of light-delivery parameters is required, as even modest intracranial heating can confound interpretation of optogenetic experiments.

Development of Squat-and-Smile Test as Proxy for Femoral Shaft Fracture-Healing in Patients in Dar es Salaam, Tanzania.

BACKGROUND: There are few validated instruments that serve as a proxy for fracture-healing after lower-extremity trauma in low-resource settings. The squat-and-smile test (S&S) has been under development by SIGN (Surgical Implant Generation Network) Fracture Care International to monitor outcomes of lower-extremity long-bone fractures after intramedullary nailing in resource-limited settings. The goals of this study were to develop and identify domains of the S&S test. METHODS: The S&S domains were developed through an iterative process, and consensus was achieved regarding 3: squat depth, support needed to squat, and facial expression. Adult patients with an OTA/AO type-32 femoral shaft fracture were included in this retrospective study and had the S&S administered at 6 weeks and 3, 6, and 12 months postoperatively. Two authors independently assessed photographs of the patients performing the S&S. S&S domains were correlated with the EuroQol 5-Dimensions (EQ-5D) index score, and comparisons were made between S&S domains and reoperation status. Interrater and test-retest reliability was assessed using the kappa statistic. Sensitivity and specificity analyses were performed. RESULTS: Six hundred and nine S&S images were evaluated for 231 patients. Each domain improved over time and correlated positively with EQ-5D scores (p < 0.05). Squat depth and support needed to squat correlated with the need for a reoperation (p ≤ 0.01), and both had high specificity (0.95 and 0.97, respectively) for ruling out the need for a reoperation at 1 year. All 3 domains had high test-retest reliability (κ = 0.95, 0.92, and 0.96). Squat depth and need for support also had strong interrater reliability (κ = 0.75 and 0.78). CONCLUSIONS: The S&S is a potential tool for monitoring clinical and functional outcome of femoral shaft fractures in low-resource settings. Our data support the binary assessment of squat depth and need for support, but not facial expression, as a proxy for fracture-healing. Future prospective studies in external populations are warranted to evaluate the validity, reliability, and responsiveness of the S&S. CLINICAL RELEVANCE: The S&S provides a valuable proxy for femoral shaft fracture assessment for middle to low-income countries because it is locally relevant (based on squatting), it is easy to administer, and assessment can be performed remotely via mobile telephone or text messaging.

The extent of pediatric orthopaedic research in low- and middle-income countries and the impact of academic collaboration on research quality: a scoping review.

INTRODUCTION: This review aims to (1) assess the breadth of pediatric orthopaedic research in low- and middle-income countries (LMICs) and (2) determine the impact of academic collaboration (an LMIC and a non-LMIC investigator) in published LMIC research. METHODS: Pediatric orthopaedic clinical studies conducted in LMICs from 2004 to 2014 were extracted from Embase, Cochrane, and Pubmed databases. Of 22,714 searched studies, 129 met inclusion criteria. RESULTS: 85% generated low-quality evidence (level IV or lower). 21% were collaborative, and these were more likely than non-collaborative papers to generate level III evidence or higher (25% vs 13%, p = 0.141). DISCUSSION: Pediatric orthopaedic research produced by LMICs rarely achieves level I-III evidence, but collaborative studies are associated with higher levels of evidence. LEVEL OF EVIDENCE: N/A.

Clinical Research Course for International Orthopaedic Surgeons: 2-Year Outcomes.

BACKGROUND: Although orthopaedic trauma occurs at higher rates in low- and middle-income countries (LMICs), most research on this topic is conducted in high-resource settings. Few initiatives exist to promote local research in LMICs. Investigators created the Institute for Global Orthopaedics and Traumatology (IGOT) International Research Symposium to promote local research initiatives by surgeons practicing in low-resource environments. The purpose of this study is to determine the efficacy of this symposium in teaching orthopaedic surgeons practicing in LMICs how to conduct clinical research. METHODS: In this prospective observational study, orthopaedic surgeons from LMICs with no formal research training were recruited to attend the 1-day IGOT International Research Symposium in San Francisco. A survey was administered immediately before and after the symposium to inquire about the participants' confidence in different aspects related to research using a 1-5 Likert scale. A second survey, conducted 2 years later, recorded the attendees' research productivity after the workshop. RESULTS: Forty-three participants representing 10 different LMICs from Africa and Asia attended the 2013 course. At 2 year postcourse, participants reported starting 25 research projects, authored 7 "accepted or published manuscripts" (vs. 1 before the course; P < 0.01), and were selected for 12 podium or poster presentations (vs. 3 before the course; P < 0.01). Two research symposium attendees received "Top International Forum Paper" at the 2015 Orthopaedic Trauma Association Annual Meeting. DISCUSSION: A 1-day research course resulted in increased participant confidence in conducting research. This was associated with greater research productivity by participants 2 years later. These results suggest that the IGOT International Research Symposium can improve the number of initiated research projects by surgeons in LMICs.

Orthopaedic Trauma in the Developing World: Where Are the Gaps in Research and What Can Be Done?

PURPOSE: There are an estimated 1.2 million deaths from road traffic injuries annually, disproportionately affecting patients in low-resource settings. The purpose of this scoping review is to identify knowledge gaps in global orthopaedic trauma in an effort to help prioritize future research. METHODS: Using the 6-stage Arksey and O'Malley framework for conducting a scoping review, orthopaedic trauma literature was reviewed over a ten-year period from 2004 to 2014. Studies from low-resource settings were included and categorized by geographic location, anatomic region, study type, and level of evidence. RESULTS: Of 548 included studies, 51.4% were from low- and middle-income countries in South Asia and 33.7% were from sub-Saharan Africa. Therapeutic (53.3%), epidemiologic (26.4%), and qualitative (8.9%) studies were most common. Only 10.2% of the studies were considered high level of evidence, whereas the vast majority (89.8%) was level 3 or below. Overall, lower extremity injuries were much more frequently represented in the literature compared with upper extremity injuries (233 vs. 78). Pelvic and acetabular fractures were the least studied anatomic region of the lower extremity (3.4%). CONCLUSIONS: Our study identified a lack of cost-effectiveness analyses pertaining to injury and intervention, paucity of high-quality research, and under-representation of pelvic, acetabular, and upper extremity injuries. Improved and prioritized research in low- and middle-income countries may help optimize care and inform policy makers of how to reduce the global burden of musculoskeletal trauma.

Conducting a Randomized Controlled Trial in Tanzania: Institute for Global Orthopaedics and Traumatology and the Muhimbili Orthopaedic Institute.

INTRODUCTION: Low- and middle-income countries (LMICs) experience a large volume of orthopaedic trauma, but limited research exists to evaluate effective treatments using locally available means. Academic partners can help design and implement research studies through collaborative efforts with local investigators. We will describe the study design and lessons learned from a randomized controlled trial in Tanzania comparing outcomes of 2 operative treatments for open tibia fractures. STUDY DESIGN: The Institute for Global Orthopaedics and Traumatology at the University of California, San Francisco, and the Muhimbili Orthopaedic Institute in Dar es Salaam, Tanzania, partnered to design a prospective, randomized controlled trial. Adult patients with open tibia fractures were randomized to receive either intramedullary nailing or external fixation as definitive fixation. Our primary outcome was the rate of reoperation, and secondary outcomes included EQ-5D, pain, function, radiographic union, and return to work. RESULTS: We enrolled 40 patients in a pilot study that informed improvements in the study design and standard operating procedures. These modifications included development of a specific outline of the technical standards for each surgical intervention and held training workshops to disseminate this knowledge among operative surgeons. This resulted in the successful enrollment and standardized treatment of our target sample of 240 patients. DISCUSSION: There are several challenges in conducting high-quality, international research. Keys for success include maintaining a strong relationship between partners, having local research coordinators, simplifying data collection and storage, and incentivizing patients to attend follow-up visits.

Effects of the T-type calcium channel antagonist Z944 on paired associates learning and locomotor activity in rats treated with the NMDA receptor antagonist MK-801.

RATIONALE: Currently available antipsychotics are unsatisfactory given their side effects and limited efficacy for the cognitive symptoms of schizophrenia. Many currently available drugs, such as haloperidol, are T-type calcium channel antagonists in addition to their well-established antagonism of dopamine D2 receptors. Thus, preclinical research into the effects of T-type calcium channel antagonists/blockers in behavioral assays related to schizophrenia may inform novel therapeutic strategies. OBJECTIVES: We explored the effects of a recently developed highly selective T-type calcium channel antagonist, Z944 (2.5, 5.0, 10.0 mg/kg), on the MK-801 (0.15 mg/kg) model of acute psychosis. METHODS: To examine the effects of Z944 on behaviors relevant to schizophrenia, we tested touchscreen-based paired associates learning given its relevance to the cognitive symptoms of the disorder and locomotor activity given its relevance to the positive symptoms. RESULTS: Acute treatment with Z944 failed to reverse the visuospatial associative memory impairments caused by MK-801 in paired associates learning. The highest dose of drug (10.0 mg/kg) given alone produced subtle impairments on paired associates learning. In contrast, Z944 (5.0 mg/kg) blocked the expected increase in locomotion following MK-801 treatment in a locomotor assay. CONCLUSIONS: These experiments provide support that Z944 may reduce behaviors relevant to positive symptoms of schizophrenia, although additional study of its effects on cognition is required. These findings and other research suggest T-type calcium channel antagonists may be an alternative to currently available antipsychotics with less serious side effects.

Acute stress, but not corticosterone, facilitates acquisition of paired associates learning in rats using touchscreen-equipped operant conditioning chambers.

Acute stress influences learning and memory in humans and rodents, enhancing performance in some tasks while impairing it in others. Typically, subjects preferentially employ striatal-mediated stimulus-response strategies in spatial memory tasks following stress, making use of fewer hippocampal-based strategies which may be more cognitively demanding. Previous research demonstrated that the acquisition of rodent paired associates learning (PAL) relies primarily on the striatum, while task performance after extensive training is impaired by hippocampal disruption. Therefore, we sought to explore whether the acquisition of PAL, an operant conditioning task involving spatial stimuli, could be enhanced by acute stress. Male Long-Evans rats were trained to a predefined criterion in PAL and then subjected to either a single session of restraint stress (30 min) or injection of corticosterone (CORT; 3 mg/kg). Subsequent task performance was monitored for one week. We found that rats subjected to restraint stress, but not those rats injected with CORT, performed with higher accuracy and efficiency, when compared to untreated controls. These results suggest that while acute stress enhances the acquisition of PAL, CORT alone does not. This dissociation may be due to differences between these treatments and their ability to produce sufficient catecholamine release in the amygdala, a requirement for stress effects on memory.