Computerized surgical navigation resection of pelvic region simulated bone tumors using skin fiducial marker registration: an in vitro cadaveric study.

INTRODUCTION: Computerized surgical navigation system guidance can improve bone tumor surgical resection accuracy. This study compared the 10-mm planned resection margin agreement between simulated pelvic-region bone tumors (SPBT) resected using either skin fiducial markers or Kirschner (K)-wires inserted directly into osseous landmarks with navigational system registration under direct observation. We hypothesized that skin fiducial markers would display similar resection margin accuracy. METHODS: Six cadaveric pelvises had one SPBT implanted into each supra-acetabular region. At the left hemi-pelvis, the skin fiducial marker group had guidance from markers placed over the pubic tubercle, the anterior superior iliac spine, the central and more posterior iliac crest, and the greater trochanter (5 markers). At the right hemi-pelvis, the K-wire group had guidance from 1.4-mm-diameter wires inserted into the pubic tubercle, and 3 inserted along the iliac crest (4 K-wires). The senior author, a fellowship-trained surgeon performed "en bloc" SPBT resections. The primary investigator, blinded to group assignment, measured actual resection margins. RESULTS: Twenty of 22 resection margins (91%) in the skin fiducial marker group were within the Bland-Altman plot 95% confidence interval for actual-planned margin mean difference (mean = -0.23 mm; 95% confidence intervals = 2.8 mm, - 3.3 mm). Twenty-one of 22 resection margins (95%) in the K-wire group were within the 95% confidence interval of actual-planned margin mean difference (mean = 0.26 mm; 95% confidence intervals = 1.7 mm, - 1.1 mm). CONCLUSION: Pelvic bone tumor resection with navigational guidance from skin fiducial markers placed over osseous landmarks provided similar accuracy to K-wires inserted into osseous landmarks. Further in vitro studies with different SPBT dimensions/locations and clinical studies will better delineate use efficacy.

In vitro and in vivo evaluation of the efficacies of commercial probiotics and disinfectant against acute hepatopancreatic necrosis disease and luminescent vibriosis in Litopenaeus vannamei.

The bioactivities of two commercially available probiotics and one chemical disinfectant were tested against strains of Vibrio parahaemolyticus (VPAHPND) and V. harveyi. This study aimed to determine shrimp pathogenic Vibrios' in vitro and in vivo sensitivities to commercial probiotics and a chemical disinfectant. The probiotics and disinfectant were tested first in vitro, followed by the in vivo trials. Results showed that upon administration of probiotics either through diet or adding into the tank water, the survivability of shrimp was increased during challenge with VPAHPND and V. harveyi. Also, the disinfectant was tested against the same pathogens and showed positive bactericidal effects at 2500 ppm and 5000 ppm. The present findings suggest that adding probiotics to the rearing water or the shrimp feeds effectively prevents infection by lowering the load of pathogenic bacteria. In comparison, the effectiveness of the disinfectant (PUR) depends on its appropriate concentration and timing of application. It is not only limited to rearing water but is also applicable for decontaminating pond liners, tanks, and other paraphernalia.

The Use of a Robotic Arm for Fixation of Pelvic Fractures.

OBJECTIVES: The objective of this study was to evaluate unplanned cortical or neuroforaminal violation of iliosacral and transsacral screw placement using fluoroscopy versus screw placement using a robotic arm. DESIGN: This is a prospective cohort study. SETTING: Single surgeon, single North American level 1 trauma center. PATIENTS: Radiographic and clinical data for 21 consecutive adult trauma patients with pelvic ring fractures undergoing surgical treatment were prospectively collected. Treatment consisted of iliosacral and/or transsacral screws with or without anterior fixation. INTERVENTION: Ten patients were treated with the assistance of a robotic arm. Eleven patients were treated with standard fluoroscopic techniques. MAIN OUTCOME MEASUREMENTS: Thirty-two screws were placed and evaluated with postoperative computed tomography or O-arm spins to assess unplanned cortical or neuroforaminal violation. Violations were graded according to the Gertzbein and Robbins system for pedicle screw violation, categorizing screw violation in 2-mm increments. The postoperative images were blindly reviewed by 5 fellowship-trained orthopaedic traumatologists. The treating surgeon was excluded from review. RESULTS: The Mann-Whitney U test on the Gertzbein and Robbins system results demonstrated significantly (P = 0.02) fewer violations with robotic assistance. χ2 analysis of whether there was a cortical violation of any distance demonstrated significantly (P = 0.003) fewer cortical violations with robotic assistance. There were no neurovascular injuries in either group. CONCLUSION: Robotic assistance demonstrated significantly fewer unplanned cortical or neuroforaminal violations. Further research is needed with additional surgeons and sites to evaluate the accuracy of iliosacral and transsacral screw placement with robotic assistance. LEVEL OF EVIDENCE: Therapeutic, level II.

Early intramedullary nailing of bilateral femur fractures: who might benefit most?

INTRODUCTION: Identifying which patients can receive immediate intramedullary nailing (IMN) after bilateral femoral shaft fracture may improve health-related quality of life outcomes and decrease healthcare costs. This retrospective study evaluated the perioperative factors that guided emergency department transfer of patients to the operating room (OR) where IMN or temporizing external fixation (TEF) was performed, to the intensive care unit (ICU), or to the orthopedic ward. The hypothesis was that patients referred initially to the OR or to the ICU had more serious co-morbidities, complications, or orthopedic polytrauma, increasing the likelihood that they would benefit from "damage control orthopedics" and TEF use. METHODS: A Level I Trauma Center database (2010-2020) review identified the records of 23 patients that met study inclusion and exclusion criteria. Most sustained their injury in a motor vehicle accident (87%) and were not wearing a seatbelt. RESULTS: Patients transferred to the operating room had a greater body mass index and shorter times between admission and surgery. Those transferred to the OR or ICU had higher injury severity scores (ISS), higher arterial blood O2 partial pressure (paO2) values on the first post-surgical day, and had more red blood cell unit (RBCU) transfusions during hospitalization. Patients transferred to the ICU more often underwent TEF and had shorter initial surgical procedure duration. Those with pneumothorax, rib fractures, or with other orthopedic comorbidities were more often transferred to the OR or ICU and those with acute complications requiring exploratory laparotomy were transferred to the OR. CONCLUSIONS: Patients with higher BMI, ISS, greater RBCU transfusion needs, with pneumothorax, rib fractures, or acute complications requiring exploratory laparotomy were more likely to be initially transferred to the OR or ICU. Patients transferred to the orthopedic ward represented a more heterogenous group with greater possibility for benefitting from earlier definitive IMN.

Intramedullary nailing of concurrent ipsilateral fractures of the tibia and femur: primary synchronous nailing versus staged osteosynthesis with temporizing external fixation.

INTRODUCTION: The optimal timing to definitive osteosynthesis in the polytraumatized patient remains an unanswered question. Early total care, damage control orthopaedics, and early appropriate care have been described to manage the fractures in these patients, but there is a paucity of literature specific to ipsilateral tibial and femoral fractures. We sought the perioperative outcomes of primary simultaneous intramedullary nailing (IMN) versus temporizing external fixation (EF) of both fractures. METHODS: A chart review of all patients who sustained fractures of the ipsilateral femur and tibia that were definitively treated with (IMN) from January 2010 to December 2020 was performed. Patients who underwent initial EF and those that were primarily treated with IMNs were examined. RESULTS: IMNs and EF were the initial treatment in 23 and 16 patients, respectively. The mean (range) injury severity score (ISS) was 23.3 (33) in the EF group vs. 18.5 (34) in the IMN group, (p = 0.0686). The EF group had a higher total transfused units of packed red blood cells 7.4 vs. 2.8, the mean initial operative time was 236 vs. 282.6 (min), (p = 0.7399), a longer mean total operative time 601.78 vs. 236 (min), and longer mean length of stay 15.6 vs. 11 (days), (p < 0.5). Rates of complications were not significantly different between groups. CONCLUSION: Primary IMN is as safe as provisional EF in the adequately resuscitated patient with ipsilateral femoral and tibial fractures. This implies the fixation of both fractures into a single surgery without increasing perioperative complications, and decreasing total hospital stay in patients with sufficient preoperative resuscitation.

Características de un material de control de la calidad para la implementación y control interno de laboratorios clínicos en el marco de la NMX 15189 / Characteristics of a quality control material for the implementation and internal control of clinical laboratories within the framework of NMX 15189

Este articulo tiene como objetivo describir las características necesarias que debe cumplir el material de control de la calidad analítica según la norma Mexicana (NMX-EC-15189-IMNC-2012).

Extended Anterior Approach for Proximal Femur Resection and Hip Reconstruction. Technique Description and Case Report of Three Oncologic Patients.

This retrospective case report describes an extended anterior surgical approach for treating oncologic patients with proximal femur resection and hip reconstruction. Three consecutive women (mean age: 57.3; range: 33 to 81 years) with non-Hodgkins lymphoma (one case) or breast cancer (two cases) that had metastasized to the proximal femur underwent this procedure. Outcome measurements included timed-up-and-go, visual analog scale (VAS) for pain, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores. Independent walking distance was also recorded. At a mean of 14 months postoperatively, all three patients had returned to independent flat surface and stair ambulation with minimal hip pain. Normal active hip flexion and extension range of motion were also restored. All patients had ≥ 4/5 involved hip manual muscle test strength. The surgical approach we described enabled effective return to independent flat surface and stair ambulation.

Intra-articular Fracture Pattern in Intercondylar Distal Femur Fractures: An Analysis of Frequency and Major Fracture Fragments.

INTRODUCTION: The treatment of intercondylar distal femur fractures requires anatomic reduction of intra-articular fragments and absolute fixation. Preoperative planning is necessary to understand fracture morphology. All fracture lines need to be recognized as the primary implant may not capture all articular fragments, mainly when coronal plane fractures are present. Oftentimes, independent interfragmentary compression screws are necessary. No recent studies have visually mapped out the distal femur articular fracture fragments necessary for absolute fixation. The objectives of this study are to determine the frequency of coronal plane fractures in intercondylar distal femur fractures and describe the pattern of intra-articular fracture fragments. MATERIALS AND METHODS: The hospital's trauma registry was queried for distal femur ORIF CPT codes logged in the past four years. A retrospective chart review was performed using the EMR and CT scans. Demographics and mechanisms of injury were analyzed. Fracture fragments were surveyed and drawn out by hand on a template for easy organization. Patients' fractures were categorized into the following groups: fractures with no intra-articular coronal plane fractures, those with medial coronal fractures, those with lateral coronal fractures, or those with both medial and lateral coronal fractures. Major fracture fragments were identified. RESULTS: A total of 55 patients were included. 26 patients (47%) were found to have no intra-articular coronal plane fractures; 6 patients (11%) were found to have medial coronal plane fractures; 15 patients (27%) were found to have lateral coronal plane fractures, and 8 patients (15%) had medial and lateral coronal plane fractures. Collectively, intra-articular coronal plane fractures were identified in 29 patients (53%) with intercondylar distal femur fractures. Four major fracture fragments along with intercondylar and condylar comminution sites were identified. DISCUSSION: Distal femur intra-articular coronal plane fractures can yield large anterior and posterior condylar fracture fragments of either the medial condyle, lateral condyle, or both condyles. Coronal plane fracture fragments must be identified to obtain absolute fixation. Our study found a higher coronal plane fracture line frequency (52.7%) than prior commonly cited studies. Surgeons must be on the lookout for anterior fracture fragments, posterior fracture fragments, and articular comminution when treating intercondylar femur fractures.

Surgical Options and Approaches for Septic Arthritis of the Native Hip and Knee Joint.

Septic arthritis (SA) of the adult knee and hip is a constantly evolving and urgent surgical issue. The epidemiology has shifted over the last few decades as have the most popular antibiotics and surgical treatments. SA of all types is increasing in the United States. There remains a high variability in the conservative and surgical management options available. This review will outline the most current understanding of the etiology and epidemiology of SA and will also discuss the distribution of causative organisms and appropriate treatments for each. A summary of evidence for different debridement and reconstructive techniques will also be presented in addition to novel areas of research to decrease the morbidity of this constantly growing problem.

Residency Selection Preferences and Orthopaedic Career Perceptions: A Notable Mismatch.

BACKGROUND: Despite near-equal enrollment of males and females in medical schools, orthopaedic surgery continues to have one of the lowest percentage of female orthopaedic residents. This suggests there may be factors that specifically influence females to select other specialties. Some of these possible reasons have been explored in other studies; however, in this study, we sought to identify latent or unobserved variables that may be influencing this difference by conducting an explanatory factor analysis of male and female residency preferences. PURPOSES/QUESTIONS: In this study, by surveying a cohort of medical students at a single institution, we asked, is there a difference between males and females (1) in their perception of orthopaedic surgery and (2) in their preferences for residency and practice? We further asked, if there are differences, (3) is there a correlation between perception and preferences for residency and practice? METHODS: A 46-question survey was sent to all current medical students (n = 628) at a major urban university with near-equal enrollment of males (55%, 345 of 628) and females (45%, 283 of 628) from September 2017 to November 2017. The survey consisted of two main parts: (1) desired attributes of a residency program and (2) perceptions of orthopaedic residency and practice. The design of the survey instruments closely followed The Checklist for Reporting Results of Internet E-Surveys (CHERRIES) checklist and went through several variations and pilot studies before release. In all, 33% (205 of 628) total medical students responded to the email survey, 55% (112 of 205) were male and 45% (93 of 205) were female. The proportion of male and female respondents matched the gender distribution of the total population surveyed, which at the time of the survey was 55% male and 45% female.The data analysis was performed using a Mann-Whitney U test and an explanatory factor analysis. The explanatory factor analysis was used to identify the correlation between survey variables among male and female students. An alpha less than 0.05 was considered significant for the Mann-Whitney U test and a factor greater than 0.5 was considered significant for the factor analysis. RESULTS: Both male and female students ranked "work-life balance" and "variety in specialty" among the top three most important preferences. Females ranked "range of practice options," higher than males (72% females versus 60% males, r = 0.18; p = 0.009), and males ranked "previous exposure to the specialty" higher than females (65% females versus 71% males, r = 0.03; p = 0.70). Both male and female students had similar overall perceptions of orthopaedic surgery. Both males and females indicated that orthopedics is "male dominated," has "competitive entrance requirements," and requires "long residency work hours." They differed in their perception of "requires physical strength" (60% females versus 38% males, r = 0.28; p < 0.0005), and by how much orthopaedics is "male dominated" (95% females versus 77% males, r = 0.26; p < 0.0005). The factor analysis recognized that, although male and female students do have some similar residency preferences, the influence or weighing of those preferences is different for male and female students. In a manner similar to a personality assessment, the factor analysis produced four latent factors that can help explain variation seen in responses and helped identify influential factors that were not directly tested by the survey. The first such latent factor for females consisted of "work-life balance," "residency length," 'residency work hours," and "family-friendly specialty." Although the first latent factor for males consisted of "prestige," "income potential," "grade or step scores," and "competitiveness of residency program." The three subsequent latent factors also displayed variation in the make-up of the latent factors between males and female students. CONCLUSIONS: This study of medical students at an urban medical school found that male and female students shared many preferences for residency specialties and held many of the same perceptions regarding orthopaedic surgery. The explanatory factor analysis indicated that male and female students weight preferences differently when selecting a specialty; this difference may account for the large differences in proportion between males and females in orthopaedic residency. CLINICAL RELEVANCE: Attracting talented residents and attending physicians is important for the success of any medical department. Although orthopaedics attracts some of the most talented students, these students are predominantly male. By identifying the multifactorial areas that may be inadvertently discouraging females from applying, orthopaedic residency programs may be able to better address those issues and attract the best talent of both genders.

Are Skin Fiducials Comparable to Bone Fiducials for Registration When Planning Navigation-assisted Musculoskeletal Tumor Resections in a Cadaveric Simulated Tumor Model?

BACKGROUND: To improve and achieve adequate bony surgical margins, surgeons may consider computer-aided navigation a promising intraoperative tool, currently applied to a relatively few number of patients in whom freehand resections might be challenging. Placing fiducials (markers) in the bone, identifying specific anatomical landmarks, and registering patients for navigated resections are time consuming. To reduce the time both preoperatively and intraoperatively, skin fiducials may offer an efficient and alternative method of navigation registration. QUESTIONS/PURPOSES: (1) Does preoperative navigation using skin fiducials for registration allow the surgeon to achieve margins similar to those from bone fiducial registration in a simulated lower extremity tumor resection model in cadavers? (2) Does the use of preoperative navigation using skin fiducials for registration allow the surgeon to achieve similar bony margins in pelvic resections of simulated tumors as those achieved in long-bone resections using only skin fiducials for navigation in a cadaver model? METHODS: Simulated bone tumor resections were performed in three fresh-frozen cadavers with intact pelvic and lower-extremity anatomy using navigation guidance. We placed 5-cm intraosseous cement simulated bone tumors in the proximal/distal femur (n = 12), and proximal/distal tibia (n = 12) and pelvis (supraacetabular; n = 6). After bone tumor implantation, CT images of the pelvis and lower extremities were obtained. Each planned osseous resection margin was set at 10 mm. Navigation registration was performed for each simulated tumor using bone and skin markers that act as a point of reference (fiducials). The simulated bone tumor was resected based on a resection line that was established with navigation, and the corresponding osseous margins were calculated after resection. These margins were determined by an orthopaedic surgeon who was blinded to resection planning by the removal of cancellous bone around the cement simulated tumor. The shortest distance was measured from the cement to the resection line. Smaller mean differences between planned and postoperative margins were considered accurate. Independent t-tests were conducted to assess measurement differences between planned and postoperative margins at the 95% CI. Bland-Altman analyses were conducted to compare the deviation in margin difference between planned and postoperative margins in skin and bone fiducial registration, respectively. RESULTS: In all, 84 total resection margins were measured with 48 long bone and 20 pelvic obtained with skin fiducials and 16 long bone obtained with bone fiducials. The planned mean margin was 10 mm for all long bone and pelvic resections. We found that skin fiducial and bone fiducial postoperative margins had comparable accuracy when resecting long bones (10 ± 2 mm versus 9 ± 2 mm, mean difference 1 [95% CI 0 to 2]; p = 0.16). Additionally, skin fiducial long bone postoperative margins were comparable in accuracy to pelvic supraacetabular postoperative margins obtained with skin fiducials (10 ± 2 mm versus 11 ± 3 mm, mean difference -1 mm [95% CI -3 to 1]; p = 0.22). When comparing the deviation in margin difference between planned and postoperative margins in skin and bone fiducial registration, 90% (61 of 68) of skin fiducial and 100% (16 of 16) bone fiducial postoperative margins fell within 2 SDs. CONCLUSIONS: In this pilot study, skin fiducial markers were easy to identify on the skin surface of the cadaver model and on CT images used to plan margins. This technique appears to be an accurate way to plan margins in this model, but it needs to be tested thoroughly in patients to determine if it may be a better clinical approach than with bone fiducials. CLINICAL RELEVANCE: The margins obtained using skin fiducials and bone fiducials for registration were similar and comparable in this pilot study with a very small effect size. Boundaries of the simulated tumors were not violated in any resections. Skin fiducials are easier to identify than bone fiducials (anatomic landmarks). If future clinical studies demonstrate that margins obtained using skin fiducials for registration are similar to margins obtained with anatomical landmarks, the use of navigation with skin fiducials instead of bone fiducials may be advantageous. This technique may decrease the surgeon's time used to plan for and localize registration points and offer an alternative registration technique, providing the surgeon with other registration approaches.

Tibia fractures and NSAIDs. Does it make a difference? A multicenter retrospective study.

PURPOSE: The purpose of this study was to compare healing time for diaphyseal tibia fractures (OTA/AO 42 A, B, C) treated with intramedullary nailing (IMN) in one geographic cohort using nonsteroidal anti-inflammatory drugs (NSAIDs) for post-operative pain control to that of another geographic cohort using opioid medications. The groups represent differing cultural approaches to post-operative pain control. We hypothesized there would be no difference in healing time. METHODS: Tibia fractures presenting at two level I trauma centers located in different countries between January 1, 2010 and December 31, 2017 were retrospectively screened for enrollment. Fractures classified as OTA/AO 42 A, B, or C that were treated with IMN and had radiographic follow up to union were included. At hospital discharge, one cohort (n = 190) was prescribed NSAIDs and the other (n = 182) was prescribed opioids for pain control. Each analgesic method represented the standard of care for that location. Fracture union was defined as cortical bridging in at least 3 out of 4 cortices on AP and lateral radiographs. The primary outcome was healing time on radiographic evaluation. RESULTS: There was no statistically significant difference in healing time between the opioid and NSAID groups: 185 vs 180.5 days respectively (p = 0.64). Both groups had similar mean age. Student t-tests were run to compare rates of tobacco use, diabetes mellitus (DM), open fractures, and polytrauma between the two groups. The opioid cohort had statistically significant higher rates of tobacco use, DM, and polytrauma. The NSAID cohort, however, had a larger number of open fractures. CONCLUSION: The difference in healing time between the NSAID and opioid groups was not statistically significant. The deleterious effect of NSAID use on fracture healing has been debated for decades. Numerous animal studies have supported this theory; however, high quality clinical studies in humans have not provided convincing evidence to substantiate this negative effect. Our study suggests that NSAIDs may be used safely and effectively in the acute phase of fracture healing without significantly increasing the risk of delayed union or nonunion. Prospective randomized studies are necessary to rule out the negative effect of NSAIDS on bone healing.

Skin fiducial markers enable accurate computerized navigation resection of simulated soft tissue tumors: A static cadaveric model pilot study.

BACKGROUND: This static cadaveric model pilot study evaluated the agreement between planned and resected margins of simulated soft tissue tumors (SSTT) using skin fiducial markers for computerized navigation registration. METHODS: Markers were applied before magnetic resonance imaging scans of lower extremities implanted with SSTT. A navigation pointer was used for registration and to guide SSTT resection with approximately 10 mm planned margins. Digital calipers were used to measure resection margins. Kolmogorov-Smirnov tests were used to confirm measurement normality. A one-sample t test was used to determine measurement group differences (P ≤ 0.05). Bland-Altman analysis and histogram plots compared planned and resected margins. RESULTS: Ninety-eight resection margins were measured. The planned margin mean was 10.0 mm (95% confidence interval [CI] = 9.8-10.2 mm) and the resected margin mean was 11.5 mm (95% CI = 11.0-12.1 mm). One-sample t test results identified a 0.75 mm, 95% CI = 0.5-0.99 mm difference (P < 0.001). Good measurement agreement was observed with 94.9% (93/98) of resections occurring within two standard deviations of the mean measurement difference. CONCLUSIONS: Skin fiducial marker use for computerized navigation system registration displayed promising results. With further research, these markers may become an effective, noninvasive method for aiding in soft tissue tumor resection.

Comparison between suprapatellar and parapatellar approaches for intramedullary nailing of the tibia. Cadaveric study.

Intramedullary nailing is one viable option for treating fractures of the tibia with a short, proximal segment. For a procedure being carried out with the knee in a semi-extended position, either a suprapatellar or parapatellar approach may be used. The objective of this study is to demonstrate whether the entry point for tibia nails is obtainable through suprapatellar or parapatellar approaches and to evaluate the most frequent injuries of the knee with these two approaches. MATERIALS AND METHODS: Paired legs from 10 fresh frozen cadavers were used. An arthroscopy was performed in each knee, documenting the status of the knee prior to the insertion of the tibia nail. In a random manner, the left or right leg underwent nailing with a suprapatellar or parapatellar approach in a semi-extended position. Fluoroscopy was utilized in each case to localize the entry point, and a tibia nail was inserted in all cases. A knee arthrotomy was then performed and the status of the following structures was assessed: patella and trochlea cartilage, tibia plateau cartilage, inter-meniscal ligament, lateral and medial meniscus, and the ACL. RESULTS: The correct fluoroscopy entry point was achieved in all of the specimens (20). Three legs (3/10) with parapatellar approach had intra-articular disruption. In legs with a suprapatellar approach, patellar cartilage and trochlea cartilage damage was found in two of the specimens, respectively. There was one specimen with cartilage damage in the parapatellar approach. There were no meniscal injuries. Partial laceration of the intermeniscal ligament was found in three of the knees for each approach. One ACL injury was found in the suprapatellar group. Mean distance from the entry point to major structures is not significantly different with either approach. (p=0.45). CONCLUSIONS: A good fluoroscopic entry point can be achieved using either the parapatellar or suprapatellar approach. The parapatellar approach for tibia nailing has similar rate of soft tissue damage compared to the suprapatellar approach. The suprapatellar approach damaged the cartilage in one-third of the cases and if cartilage injury occurs with the parapatellar approach, this is located in a low risk area.

Limb Sparing Resection for Tumors Involving the Distal Humerus and Reconstruction with a Modular Endoprosthesis.

Tumors involving the distal humerus are extremely rare. Those tumors can be safely resected and then the extremity reconstructed. In this article, we present a series of patients treated with hinged semiconstrained modular distal humeral replacement for reconstruction following wide resection of tumors of the distal humerus. We retrospectively reviewed the charts of nine patients treated for tumors of the distal humerus between 2002 and 2013. The diagnoses consisted of three primaries, five metastatic, and one benign aggressive tumor. There were four male and five female patients ranging in age from 36 to 78 years old. Patients were followed for an average of 34 months (3 to 75 months). The functional status was rated using the Musculoskeletal Tumor Score System (MSTS). Five of the nine cases presented as a pathologic fracture. Six of the nine patients died of their diseases at a mean of 17 months after main surgery. Three patients were alive and disease-free at a mean follow-up of 69 months (63 to 75 months). Seven patients demonstrated significant improvement in their elbow pain after the endoprosthetic surgery. The MSTS score for the nine cases was 81% (63% to 97%). Tumors of the distal humerus can be safely resected through an anterior approach. Once the tumor is resected, the resultant defect is reconstructed with a modular semiconstrained prosthesis. This technique allows safe tumor resection with a low complication rate and good functional results.

Mexican experience on migration and development 1990-2013 / Experiência mexicana refrerente a migração e desenvolvimento 1990-2013

After 40 years of a long rising emigration from Mexico to the United States, the number of Mexicans increased to 12 million in 2006, while the increased input of remittances reached $26 million dollars in 2007. Yet, the increasing migration and remittances mainly in Zacatecas and Michoacan states do not achieve economic and social development because of the persistent backwardness, unemployment and marginalization. It demands the need for new Policies of Development, Migration and Human Rights that allow exercising the right to not emigrate in a medium term. Positive products of this long migration are the Mexican Migrant Clubs and their Federations that elaborated the concrete development proposals. Whereas, the possibility that these proposals can become a Development, Migration and Human Rights, Comprehensive and Long Term State Policy will depend on the capacity and participation of Mexican Civil Society and the Transnational Communities in both countries. (AU).

Depois de 40 anos de constante aumento da emigração do México para os Estados Unidos, o número de mexicanos residentes naquele país chegou a 12 milhões em 2006, enquanto as remessas atingiram seu ápice em 2007, com 26 milhões de dólares. No entanto, o crescimento da migração e das remessas, principalmente nos Estados de Zacatecas e Michoacán, não produziu o esperado desenvolvimento econômico e social, por causa da persistência do atraso, do desemprego e da marginalização. Precisa-se de novas políticas de desenvolvimento, migração e direitos humanos, que permitam, a médio prazo, o exercício do direito a não emigrar. Um produto positivo deste longo período de migração é a constituição de clubes de Migrantes Mexicanos e suas Federações que elaboraram propostas concretas de desenvolvimento. A possibilidade de que estas propostas se tornem políticas públicas de desenvolvimento, migração e direitos humanos, abrangentes e de longo prazo, dependerá da capacidade e da participação da sociedade civil mexicana e das comunidades transnacionais em ambos os países. (AU).

Migrações internacionais e desenvolvimento na América Latina: avanços e desafios / International migration and economic development in Latin America: advances and challenges

Este trabalho tem por finalidade analisar como a economia latino-americana evoluiu, ao longo do século XX, por meio de três modelos econômicos diferentes, o primário-exportador, o de substituição de importações e o modelo neoliberal - no qual as migrações internacionais e as remessas adquirem grandes dimensões - como conseqüência dos graves impactos sociais que esse modelo provoca nos países da região desde os anos setenta até o início do século XXI. Em contraposição ao que defendia o Banco Interamericano de Desenvolvimento (BID), as remessas não foram a alavanca para o desenvolvimento econômico e social no continente, o qual passou a ser, perigosamente, mais dependente das remessas e vulnerável em relação à situação das economias receptoras de migrantes. A crise hipotecária norteamericana em 2007 e 2008 evidencia a necessidade de reorientação do modelo neoliberal como se tem tentado atualmente na América do Sul, em prol de um modelo endógeno, com crescimento dos diferentes setores e regiões, tendo em vista a equidade e bem-estar de toda a população.(AU)

The paper aims to analyze how the Latin American economy evolved, throughout the twentieth century by means of three different economic models; the primary exporter, the import substitution one and the neoliberal model – in which international migration and remittances acquire big dimensions – as a consequence of grave social impacts which this model hás provoked in countries of the region since the 70s until century XXI. In contraposition to what the Inter-American Development Bank defends, remittances were not the lever for economic and social development on the continent. Instead, Latin América dangerously became more dependent on remittances and vulnerable in relation to the migrant receiving economy. The North-American subprime mortgage crisis in 2007 and 2008 obviated the necessity for reorientation of the neo-liberal model as recently attempted in South América in favor of na endogenous model, with growth of different sectors and regions, with the goal of promoting equity and the social well-being of the entire population.(AU)

The STAT pathway mediates late-phase immunity against Plasmodium in the mosquito Anopheles gambiae.

The STAT family of transcription factors activates expression of immune system genes in vertebrates. The ancestral STAT gene (AgSTAT-A) appears to have duplicated in the mosquito Anopheles gambiae, giving rise to a second intronless STAT gene (AgSTAT-B), which we show regulates AgSTAT-A expression in adult females. AgSTAT-A participates in the transcriptional activation of nitric oxide synthase (NOS) in response to bacterial and plasmodial infection. Activation of this pathway, however, is not essential for mosquitoes to survive a bacterial challenge. AgSTAT-A silencing reduces the number of early Plasmodium oocysts in the midgut, but nevertheless enhances the overall infection by increasing oocyst survival. Silencing of SOCS, a STAT suppressor, has the opposite effect, reducing Plasmodium infection by increasing NOS expression. Chemical inhibition of mosquito NOS activity after oocyte formation increases oocyte survival. Thus, the AgSTAT-A pathway mediates a late-phase antiplasmodial response that reduces oocyst survival in A. gambiae.

Structural domains within the 3' untranslated region of Turnip crinkle virus.

The genomes of positive-strand RNA viruses undergo conformational shifts that complicate efforts to equate structures with function. We have initiated a detailed analysis of secondary and tertiary elements within the 3' end of Turnip crinkle virus (TCV) that are required for viral accumulation in vivo. MPGAfold, a massively parallel genetic algorithm, suggested the presence of five hairpins (H4a, H4b, and previously identified hairpins H4, H5, and Pr) and one H-type pseudoknot (Psi(3)) within the 3'-terminal 194 nucleotides (nt). In vivo compensatory mutagenesis analyses confirmed the existence of H4a, H4b, Psi(3) and a second pseudoknot (Psi(2)) previously identified in a TCV satellite RNA. In-line structure probing of the 194-nt fragment supported the coexistence of H4, H4a, H4b, Psi(3) and a pseudoknot that connects H5 and the 3' end (Psi(1)). Stepwise replacements of TCV elements with the comparable elements from Cardamine chlorotic fleck virus indicated that the complete 142-nt 3' end, and subsets containing Psi(3), H4a, and H4b or Psi(3), H4a, H4b, H5, and Psi(2), form functional domains for virus accumulation in vivo. A new 3-D molecular modeling protocol (RNA2D3D) predicted that H4a, H4b, H5, Psi(3), and Psi(2) are capable of simultaneous existence and bears some resemblance to a tRNA. The related Japanese iris necrotic ring virus does not have comparable domains. These results provide a framework for determining how interconnected elements participate in processes that require 3' untranslated region sequences such as translation and replication.