Impact of varying degrees of peripheral nerve blockade on experimental pressure and ischemic pain: adductor canal and sciatic nerve blocks in a human model of compartment syndrome pain.

INTRODUCTION: Early diagnosis of acute extremity compartment syndrome is crucial to timely surgical management. Pain is commonly used as an early diagnostic sign for acute extremity compartment syndrome, making regional anesthesia after lower extremity surgery controversial. This randomized study tested whether different concentrations of local anesthetics, or combinations of nerve blocks, would differentially impact the perception of acute extremity compartment syndrome-like pressure and ischemic pain. METHODS: Healthy volunteers underwent quantitative sensory testing, including determination of pressure pain thresholds and prolonged pressure/ischemic pain in the leg using a variable cuff inflation system. Subjects were randomized to receive (1) adductor canal block alone (ACB), (2) ACB with low-concentration sciatic nerve block (ACB +LC SNB), or (3) ACB with high-concentration SNB (ACB +HC SNB). For the primary outcome, we assessed block-induced increases in pressure threshold to reach 6/10 pain, and compared the degree of increase between the three groups. The main secondary outcome was a comparison of average pain score during a 5 min hold at the 6/10 pressure pain threshold between the three groups. RESULTS: All blocks raised pressure pain threshold and decreased ischemic pain, but to variable extents. Specifically, the amount the block increased pressure pain threshold was significantly different among ACB, ACB+LC SNB, and ACB+HC SNB groups (mean±SD: 24±32 mm Hg, 120±103 mm Hg, 159±93 mm Hg; p=0.002), with post hoc testing revealing ACB as less than the other two groups. Similarly, average pain scores during a prolonged/ischemic cuff hold differed among the groups (4.2±1.4, 1.4±1.7, 0.4±0.7; p<0.001), with post hoc testing revealing ACB as significantly higher. DISCUSSION: This study suggests the possible utility of titrating regional anesthesia, to provide some analgesia while still allowing acute extremity compartment syndrome detection. TRIAL REGISTRATION NUMBER: NCT04113954.

Pain, Analgesic Use, and Patient Satisfaction With Spinal Versus General Anesthesia for Hip Fracture Surgery : A Randomized Clinical Trial.

BACKGROUND: The REGAIN (Regional versus General Anesthesia for Promoting Independence after Hip Fracture) trial found similar ambulation and survival at 60 days with spinal versus general anesthesia for hip fracture surgery. Trial outcomes evaluating pain, prescription analgesic use, and patient satisfaction have not yet been reported. OBJECTIVE: To compare pain, analgesic use, and satisfaction after hip fracture surgery with spinal versus general anesthesia. DESIGN: Preplanned secondary analysis of a pragmatic randomized trial. (ClinicalTrials.gov: NCT02507505). SETTING: 46 U.S. and Canadian hospitals. PARTICIPANTS: Patients aged 50 years or older undergoing hip fracture surgery. INTERVENTION: Spinal or general anesthesia. MEASUREMENTS: Pain on postoperative days 1 through 3; 60-, 180-, and 365-day pain and prescription analgesic use; and satisfaction with care. RESULTS: A total of 1600 patients were enrolled. The average age was 78 years, and 77% were women. A total of 73.5% (1050 of 1428) of patients reported severe pain during the first 24 hours after surgery. Worst pain over the first 24 hours after surgery was greater with spinal anesthesia (rated from 0 [no pain] to 10 [worst pain imaginable]; mean difference, 0.40 [95% CI, 0.12 to 0.68]). Pain did not differ across groups at other time points. Prescription analgesic use at 60 days occurred in 25% (141 of 563) and 18.8% (108 of 574) of patients assigned to spinal and general anesthesia, respectively (relative risk, 1.33 [CI, 1.06 to 1.65]). Satisfaction was similar across groups. LIMITATION: Missing outcome data and multiple outcomes assessed. CONCLUSION: Severe pain is common after hip fracture. Spinal anesthesia was associated with more pain in the first 24 hours after surgery and more prescription analgesic use at 60 days compared with general anesthesia. PRIMARY FUNDING SOURCE: Patient-Centered Outcomes Research Institute.

Exploratory study of VVZ-149, a novel analgesic molecule, in the affective component of acute postoperative pain after laparoscopic colorectal surgery.

STUDY OBJECTIVE: VVZ-149 is a small molecule that inhibits the glycine transporter type 2 and the serotonin receptor 5-hydroxytryptamine 2A. In the present study, we investigated the efficacy and safety of VVZ-149 as a single-use injectable analgesic for treating moderate to severe postoperative pain after colorectal surgery. DESIGN: Randomized, parallel group, double-blind Phase 2 clinical trial (NCT02489526). SETTING: 3 academic institutions in the United States. PATIENTS: 60 patients undergoing laparoscopic colorectal surgery. INTERVENTIONS: A continuous 8-h intravenous infusion of VVZ-149 Injections (n = 40) or placebo (n = 20) administered after emergence from anesthesia. MEASUREMENTS: The outcome measures included pain intensity (PI), opioid consumption via patient-controlled analgesia (PCA), and rescue dosing provided "as needed". Early rescue dosing with opioids postoperatively was associated with preoperative negative affect (anxiety, depression, and pain catastrophizing), enabling it to be used as an indirect measure of the affective component of pain. Efficacy outcomes were compared between treatment groups based on preoperative negative affect and early rescue dosing of opioids. MAIN RESULTS: Postoperative PI was non-significantly lower in patients receiving VVZ-149 compared to those receiving placebo. The VVZ-149 group had a 34.2% reduction in opioid consumption for 24 h post-dose, along with fewer PCA demands. Somnolence and headache was higher in the intervention group. For patients characterized by high levels of preoperative negative affect, the VVZ-149 group experienced a significant pain reduction and 40% less opioid use compared to the placebo group. CONCLUSIONS: VVZ-149 resulted in a non-significant reduction of postoperative pain during the first 8 h after surgery. Post hoc analysis indicates that VVZ-149 may benefit patients with negative affect who otherwise have higher postoperative opioid use. REGISTRATION NUMBER: www.clinicaltrials.gov, ID: NCT02489526.

Ultrasound-Guided Nerve Blocks: Suggested Procedural Guidelines for Emergency Physicians.

Acute pain is one of the most frequent, and yet one of the most challenging, complaints physicians encounter in the emergency department (ED). Currently, opioids are one of several pain medications given for acute pain, but given the long-term side effects and potential for abuse, alternative pain regimens are sought. Ultrasound-guided nerve blocks (UGNB) can provide quick and sufficient pain control and therefore can be considered a component of a physician's multimodal pain plan in the ED. As UGNB are more widely implemented at the point of care, guidelines are needed to assist emergency providers to acquire the skill necessary to incorporate them into their acute pain management.

Impact of the 2018 Society of Critical Care Medicine Pain, Agitation/Sedation, Delirium, Immobility, and Sleep Guidelines on Nonopioid Analgesic Use and Related Outcomes in Critically Ill Adults After Major Surgery.

We compared ICU nonopioid analgesic use, opioid use, and pain before and after Pain, Agitation/Sedation, Delirium, Immobility, and Sleep guideline publication at one academic center among critically ill adults receiving an opioid infusion and greater than or equal to 24 hours of mechanical ventilation after major surgery. The 2017 (n = 77) and 2019 (n = 57) groups were similar at baseline. The 2019 (vs 2017) patients were more likely to receive scheduled IV/oral acetaminophen (84% vs 69%; p = 0.05), less likely to receive a lidocaine patch (33% vs 50%; p = 0.05), and just as likely to receive ketamine (4% vs 3%; p = 1.0), an nonsteroidal anti-inflammatory drug (7% vs 3%; p = 0.26), or gabapentin/pregabalin (16% vs 9%; p = 0.23). Daily average opioid exposure (in IV morphine milligram equivalent) was not different (70 [42-99] [2017] vs 78 mg [49-109 mg]; p = 0.94). The 2019 (vs 2017) group spent more ICU days with severe pain (p = 0.04). At our center, Pain, Agitation/Sedation, Delirium, Immobility, and Sleep guideline publication had little effect on nonopioid analgesic or opioid prescribing practices in critically ill surgical adults.

Sympathetic Blockade for the Management of Refractory Ventricular Tachycardia: A Case Report.

A 64-year-old man with a history of nonischemic cardiomyopathy (NICM) presented with electrical storm (ES). Episodes of ventricular tachycardia (VT) persisted despite endocardial catheter ablations and exhaustive pharmacotherapy. We used alternating regional anesthesia techniques, left stellate ganglion block, and proximal intercostal block to reduce sympathetic input to the heart, resulting in a significant decrease in VT burden. By using alternating catheter locations, we were able to maintain continuous sympathetic blockade for 31 days and bridge the patient to a successful orthotopic heart transplant.

Conditioned open-label placebo for opioid reduction after spine surgery: a randomized controlled trial.

ABSTRACT: Placebo effects have traditionally involved concealment or deception. However, recent evidence suggests that placebo effects can also be elicited when prescribed transparently as "open-label placebos" (OLPs), and that the pairing of an unconditioned stimulus (eg, opioid analgesic) with a conditioned stimulus (eg, placebo pill) can lead to the conditioned stimulus alone reducing pain. In this randomized control trial, we investigated whether combining conditioning with an OLP (COLP) in the immediate postoperative period could reduce daily opioid use and postsurgical pain among patients recovering from spine surgery. Patients were randomized to COLP or treatment as usual, with both groups receiving unrestricted access to a typical opioid-based postoperative analgesic regimen. The generalized estimating equations method was used to assess the treatment effect of COLP on daily opioid consumption and pain during postoperative period from postoperative day (POD) 1 to POD 17. Patients in the COLP group consumed approximately 30% less daily morphine milligram equivalents compared with patients in the treatment as usual group during POD 1 to 17 (-14.5 daily morphine milligram equivalents; 95% CI: [-26.8, -2.2]). Daily worst pain scores were also lower in the COLP group (-1.0 point on the 10-point scale; 95% CI: [-2.0, -0.1]), although a significant difference was not detected in average daily pain between the groups (-0.8 point; 95% CI: [-1.7, 0.2]). These findings suggest that COLP may serve as a potential adjuvant analgesic therapy to decrease opioid consumption in the early postoperative period, without increasing pain.

Ultrasound-guided supraclavicular vs. retroclavicular block of the brachial plexus: comparison of ipsilateral diaphragmatic function: A randomised clinical trial.

BACKGROUND: The ultrasound-guided retroclavicular block (RCB) is a recently described alternative approach to brachial plexus blockade at the level of the cords. Although more distal blockade of the brachial plexus is thought to be associated with a lower incidence of phrenic nerve block, the impact of RCB on ipsilateral diaphragmatic function has not been formally investigated. OBJECTIVE: To compare the effects of supraclavicular and retroclavicular brachial plexus block on diaphragmatic function. SETTING: A single tertiary hospital, study period from December 2017 to May 2019. DESIGN: Double-blinded, randomised study. PATIENTS: A total of 40 patients undergoing upper extremity surgery below the axilla. Exclusion criteria included significant pulmonary disease, BMI more than 40 and contra-indication to peripheral nerve block. INTERVENTIONS: Patients were randomised to supraclavicular or retroclavicular brachial plexus block with ropivacaine 0.5%. OUTCOME MEASURES: Phrenic block was assessed by measuring changes in diaphragmatic excursion using M-mode ultrasound, and maximum inspiratory volume on incentive spirometry from baseline, at 15 and 30 min postblock, and postoperatively. Comparative assessment of block characteristics included timing and distribution of sensory and motor block onset in the upper extremity, and scanning and block performance times. RESULTS: The incidence of phrenic block in the supraclavicular group was higher by ultrasound imaging (70 vs. 15%) and also by pulmonary function testing (55 vs. 5%), with both diaphragmatic excursion and maximum inspiratory volume decreasing to a greater extent after supraclavicular block (SCB) compared with RCB at 15, 30 min and postoperative time points (repeated measures analysis of variance, P < 0.001). There was no difference in timing and extent of distal arm block, but suprascapular and axillary nerves were more consistently blocked after SCB than after RCB. CONCLUSION: The current study confirms the hypothesis that a RCB is significantly less likely to affect ipsilateral diaphragmatic function than a SCB. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT02631122.

A prospective, randomized comparison of ultrasonographic visualization of proximal intercostal block vs paravertebral block.

BACKGROUND: Thoracic paravertebral blockade is an accepted anesthetic and analgesic technique for breast surgery. However, real-time ultrasound visualization of landmarks in the paravertebral space remains challenging. We aimed to compare ultrasound-image quality, performance times, and clinical outcomes between the traditional parasagittal ultrasound-guided paravertebral block and a modified approach, the ultrasound-guided proximal intercostal block. METHODS: Women with breast cancer undergoing mastectomy (n = 20) were randomized to receive either paravertebral (n = 26) or proximal intercostal blocks (n = 32) under ultrasound-guidance with 2.5 mg/kg ropivacaine prior to surgery. Block ultrasound images before and after needle placement, and anesthetic injection videoclips were saved, and these images and vidoes independently rated by separate novice and expert reviewers for quality of visualization of bony elements, pleura, relevant ligament/membrane, needle, and injectate spread. Block performance times, postoperative pain scores, and opioid consumption were also recorded. RESULTS: Composite visualization scores were superior for proximal intercostal compared to paravertebral nerve block, as rated by both expert (p = 0.008) and novice (p = 0.01) reviewers. Notably, both expert and novice rated pleural visualization superior for proximal intercostal nerve block, and expert additionally rated bony landmark and injectate spread visualization as superior for proximal intercostal block. Block performance times, needle depth, opioid consumption and postoperative pain scores were similar between groups. CONCLUSIONS: Proximal intercostal block yielded superior visualization of key anatomical landmarks, possibly offering technical advantages over traditional paravertebral nerve block. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02911168. Registred on the 22nd of September 2016.

Brachial Plexus Block with Liposomal Bupivacaine for Shoulder Surgery Improves Analgesia and Reduces Opioid Consumption: Results from a Multicenter, Randomized, Double-Blind, Controlled Trial.

OBJECTIVE: The utility of single-injection and continuous peripheral nerve blocks is limited by short duration of analgesia and catheter-related complications, respectively. This double-blind, multicenter trial evaluated the efficacy, safety, and pharmacokinetics of single-injection, ultrasound-guided brachial plexus block (BPB) with liposomal bupivacaine (LB) added to a standardized pain management protocol for shoulder surgery. METHODS: Adults undergoing total shoulder arthroplasty or rotator cuff repair were randomized to receive LB 133 mg, LB 266 mg (pharmacokinetic and safety analyses only), or placebo, added to a standardized analgesia protocol. The primary end point was area under the curve (AUC) of visual analog scale pain intensity scores through 48 hours postsurgery. Secondary end points were total opioid consumption, percentage of opioid-free patients, and time to first opioid rescue through 48 hours. Pharmacokinetic samples were collected through 120 hours and on days 7 and 10. Adverse events were documented. RESULTS: One hundred fifty-five patients received treatment (LB 133 mg, N = 69; LB 266 mg, N = 15; placebo, N = 71). BPB with LB 133 mg was associated with significantly improved AUC of pain scores (least squares mean [SE] = 136.4 [12.09] vs 254.1 [11.77], P < 0.0001), opioid consumption (least squares mean [SE] = 12.0 [2.27] vs 54.3 [10.05] mg, P < 0.0001), median time to opioid rescue (4.2 vs 0.6 h, P < 0.0001), and percentage of opioid-free patients (treatment difference = 0.166, 95% confidence interval = 0.032-0.200, P = 0.008) through 48 hours vs placebo. Adverse event incidence was comparable between groups. CONCLUSIONS: Single-injection BPB with LB 133 mg provided analgesia through 48 hours postsurgery with reduced opioid use compared with placebo after shoulder surgery.

Proof of Concept for a Novel Curriculum: Learning a Second Language during Anesthesiology Residency.

This article describes a novel curriculum for anesthesiology residents matriculating through Brigham and Women's Department of Anesthesiology. It is offered electively and provides physician residents with time to acquire language skills through a medically-focused immersion program abroad. It is designed for them to learn or improve a second language and then to speak it while practicing perioperative medicine. Ultimately, the elective curriculum will equip future anesthesiologists with the communication tools to deliver professional and compassionate patient care both within the United States and internationally.

Randomised, double-blind, parallel group, placebo-controlled study to evaluate the analgesic efficacy and safety of VVZ-149 injections for postoperative pain following laparoscopic colorectal surgery.

INTRODUCTION: In spite of advances in understanding and technology, postoperative pain remains poorly treated for a significant number of patients. In colorectal surgery, the need for developing novel analgesics is especially important. Patients after bowel surgery are assessed for rapid return of bowel function and opioids worsen ileus, nausea and constipation. We describe a prospective, double-blind, parallel group, placebo-controlled randomised controlled trial testing the hypothesis that a novel analgesic drug, VVZ -149, is safe and effective in improving pain compared with providing opioid analgesia alone among adults undergoing laparoscopic colorectal surgery. METHODS AND ANALYSIS: Based on sample size calculations for primary outcome, we plan to enrol 120 participants. Adult patients without significant medical comorbidities or ongoing opioid use and who are undergoing laparoscopic colorectal surgery will be enrolled. Participants are randomly assigned to receive either VVZ-149 with intravenous (IV) hydromorphone patient-controlled analgesia (PCA) or the control intervention (IV PCA alone) in the postoperative period. The primary outcome is the Sum of Pain Intensity Difference over 8 hours (SPID-8 postdose). Participants receive VVZ-149 for 8 hours postoperatively to the primary study end point, after which they continue to be assessed for up to 24 hours. We measure opioid consumption, record pain intensity and pain relief, and evaluate the number of rescue doses and requests for opioid. To assess safety, we record sedation, nausea and vomiting, respiratory depression, laboratory tests and ECG readings after study drug administration. We evaluate for possible confounders of analgesic response, such as anxiety, depression and catastrophising behaviours. The study will also collect blood sample data and evaluate for pharmacokinetic and pharmacodynamic relationships. ETHICS AND DISSEMINATION: Ethical approval of the study protocol has been obtained from Institutional Review Boards at the participating institutions. Trial results will be disseminated through scientific conference presentations and by publication in scientific journals. TRIAL REGISTRATION NUMBER: NCT02489526; pre-results.

Identificación y Antibiograma de Pseudomonas aeruginosa y Staphylococcus aureus en el Pabellón Infantil de Quemados del Hospital Viedma Agosto-2013 / Identification and Susceptibility of Pseudomonas aeruginosa and Staphylococcus aureus in Children's Hospital Viedma Burn Hall in August- 2013

Las infecciones nosocomiales constituyen un factor que aumenta la morbimortalidad sobre todo en el paciente inmunosuprimido como los infantiles quemados. Es por ello que este trabajo tiene como objetivo identificar Pseudomonas aeruginosa y Staphylococcus aureus en el pabellón infantil de quemados del Hospital Viedma. El estudio es de tipo descriptivo transversal, el universo fue el pabellón infantil de quemados y la muestra los materiales y equipos que estén en frecuente contacto con los niños quemados: Batas de visita, grifo del baño, manguera del equipo de suero, agarrador de cama, sábanas, manija de la puerta, sillón, paredes, agua de hidroterapia, tina de hidroterapia, frazadas estériles, estantes, tina de baño, balanza, máscara de respirador, uniforme del personal de salud, manos de las enfermeras y medio ambiente. Se realizó un hisopado, se sembró en Agar Sangre y Agar Mckoney para identificar Staphylococcus aureus y Pseudomonas aeruginosa adicionado el método de la coagulasa en las colonias de Staphylococcus aureus; posteriormente se realizó el perfil antimicrobiano. Los resultados evidenciaron la identificación de Staphylococcus aureus, no así de Pseudomonas aeruginosa, en frazadas, sábanas, frazadas estériles y manos del personal de salud. El antibiograma dio como resultado que son resistentes a la Meticilina y la colonia identificada en las frazadas estériles también es resistente a Vancomicina. Se concluye que Staphylococcus aureus coloniza varios elementos del pabellón de quemados, por otro lado hay que tener en cuenta su perfil de resistencia para tratar infecciones por esta causa dentro el pabellón de quemados del Hospital Viedma.

Nosocomial infections are factors that increase morbidity and mortality especially in the immunosuppressed patient and burned children.This study is to identify Staphylococcus aureus and Pseudomonas aeruginosa in the burn ward at the Children's "Viedma Hospital". Moreover, the study is descriptive, transversal and the universe were children's burn ward and sample materials, equipment that are in frequent contact with burned children:check robes, bathroom faucet, hose physiologic solution, grippers, bed sheets, door handle, chair, walls, water hydrotherapy, hydrotherapy tub, sterile blankets, shelves, bath tub, balance, respirator mask, uniform health person, nurses hands' and the environment. A swab test was carried out on blood agar seeded agar and Mckoney to identify Staphylococcus Aureus and Pseudomona Aeruginosa. Coagulase method was added in colonies of Staphylococcus aureus; subsequent antimicrobial profile was performed. The results showed the identification of Staphylococcus aureus, Pseudomonas aeruginosa (except this), in blankets, sheets, sterile blankets and health personnel's hands.The antibiogram showed that are resistant to Methicillin, and the colony that was identified in sterile blankets is also resistant to Vancomycin. It is concluded that Staphylococcus aureus colonizes several elements in the burn ward. On the other hand we must take account of their resistance profile in treatment of infections due to this cause in the burn ward at Viedma Hospital.

The ultrasound-guided retrolaminar block.

PURPOSE: Paravertebral blocks have gained in popularity and offer the possible benefit of reduced adverse effects when compared with epidural analgesia. Nevertheless, pulmonary complications in the form of inadvertent pleural puncture are still a recognized risk. Also, the traditional paravertebral blocks are often technically difficult even with ultrasound guidance and constitute deep non-compressible area injections. We present our experience with the first three patients receiving ultrasound-guided retrolaminar blocks for managing the pain associated with multiple rib fractures. CLINICAL FEATURES: The vertebral laminae are identified by ultrasound imaging in a paramedian sagittal plane by sequentially visualizing the pleura and ribs, transverse processes, and the corresponding laminae (from lateral to medial). The block needle is guided to contact the lamina, and the local anesthetic injectate is visualized under real-time imaging. A catheter is inserted and used for continuous analgesia. In three consecutive patients, verbal rating scale (VRS) pain scores were reduced from 10/10 to less than 5/10, and no technical difficulties, complications, or adverse effects were encountered. CONCLUSIONS: Successful analgesia was achieved in all three cases utilizing continuous infusion and intermittent boluses with ultrasound-guided retrolaminar blocks. These results show the feasibility of this approach for patients with multiple rib fractures.

La ayuda humanitaria internacional en casos de desastres / International humanitarian assistance in disaster situations

Los desastres naturales y antrópicos generan enormes pérdidas para los damnificados y afectan el desarrollo de los países, la comunidadinternacional siempre ha respondido de manera espontánea y solidaria para asistir a los damnificados en las etapas más críticas proporcionando asistencia médica, alimentación y abrigo. En este artículo se revisa en particular la respuesta del sistema de las NacionesUnidas, la participación de la Organización Panamericana de la Salud en el terremoto de Pisco, Perú y las limitaciones y dificultades parauna ayuda humanitaria efectiva.

Natural and man-made disasters huge losses for the victims and affected developing countries, the international community has alwaysresponded spontaneously and solidarity to assist the earthquake victims in the most critical stages providing medical care, food and shelter. This article reviews in particular the response of the United Nations system, the participation of the Pan American Health Organization in the earthquake in Pisco, Peru and the limitations and difficulties for effective humanitarian assistance.

Microvascular anastomosis using a photochemical tissue bonding technique.

BACKGROUND AND OBJECTIVES: Photochemical tissue bonding (PTB) combines photoactive dyes with visible light to create fluid-tight seals between tissue surfaces without causing collateral thermal damage. The potential of PTB to improve outcomes over standard of care microsurgical reanastomoses of blood vessels in ex vivo and in vivo models was evaluated. STUDY DESIGN: The mechanical strength and integrity of PTB and standard microsurgical suture repairs in ex vivo porcine brachial arteries (n = 10) were compared using hydrostatic testing of leak point pressure (LPP). Femoral artery repair in vivo was measured in Sprague-Dawley rats using either standard microvascular sutures (n = 20) or PTB (n = 20). Patency was evaluated at 6 hours (n = 10) and 8 weeks post-repair (n = 10) for each group. RESULTS: PTB produced significantly higher LPPs (1,100+/- 150 mmHg) than suture repair (350+/-40 mmHg, P<0.001) in an ex vivo study. In an in vivo study all femoral arteries in both suture and PTB repair groups were patent at 6 hours post-repair. At 8 weeks post-repair the patency rate was 80% for both groups. No evidence of aneurysm formation was seen in either group and bleeding was absent from the repair site in the PTB-treated vessels, in contrast to the suture repair group. CONCLUSION: PTB is a feasible microvascular repair technique that results in an immediate, mechanically robust bond with short- and long-term patency rates equal to those for standard suture repair.

Embryonic stem cell-derived motor neurons preserve muscle after peripheral nerve injury.

BACKGROUND: The potential of motor neuron progenitor cell transplants to preserve muscle tissue after denervation was studied in in vivo and in vitro adult mammalian model of peripheral nerve injury. METHODS: Embryonic stem cells were differentiated to induce cholinergic motor neuron progenitors. Flourescent-labeled progenitor cells were injected into the gastrocnemius muscle of Sprague-Dawley rats (n = 10) after denervation by ipilateral sciatic nerve transection. Control rats received injections of either a phosphate-buffered saline solution only (n = 12), murine embryonic fibroblast (STO) cells (n= 6), or undifferentiated embryonic stem cells (n= 6). Muscles were weighed and analyzed at 7 and 21 days using histology, histomorphometry, and immunostaining. RESULTS: Seven days after progenitor cell transplant, both muscle mass and myocyte cross-sectional area were preserved, compared with control muscles, which demonstrated muscle mass reduction to 70 percent and reduction of cross-sectional area to 72 percent of normal. Fluorescent microscopy of transplanted muscles confirmed the presence of motor neuron progenitors. Presynaptic neuronal staining of the transplants overlapped with alpha-bungarotoxin-labeled muscle fibers, revealing the presence of new neuromuscular junctions. By 21 days, muscle atrophy in the experimental muscles was equal to that of controls and no transplanted cells were observed. Co-culture of the motor neuron progenitor cells and myocytes also demonstrated new neuromuscular junctions by immunofluorescence. CONCLUSIONS: Transplanted motor neuron progenitors prevent muscle atrophy after denervation for a brief time. These progenitor cell transplants appear to form new neuromuscular junctions with denervated muscle fibers in vivo and with myocytes in vitro.

Catálogo de Ocas Bolivianas

La oca (Oxalis tuberosa Mol.), al igual que otros tubérculos, es originaria de la zona andiana.Bolivia cuenta con una grna variabilidad de esta especie, sin embargo su impotancia es sóolo relevante a nivel de algunas poblaciones donde agricultores aymaras y quechuas han mantenido esta gran riqueza genética, porque forma parte de su dieta alimenticia y del elgado cultural que van trasmitiendo de generación en generación.La oca, a difereincia de la papa, no se ha desiminado por el mundo a pesar de su agradable sabor, sus cualidades nutricionales y el potencial agroindustrial que ofrece: es considerado una especie aúun muy autóctona de la zoan andina y ha sido muy poco explorada, probablemente porque se desconoce su gran riqueza genética