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1.
N Z Med J ; 137(1591): 74-89, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38452235

ABSTRACT

Medical simulation has become an integral aspect of modern healthcare education and practice. It has evolved to become an essential aspect of teaching core concepts and skills, common and rare presentations, algorithms and protocols, communication, interpersonal and teamworking skills and testing new equipment and systems. Simulation-based learning (SBL) is useful for the novice to the senior clinician. Healthcare is a complex adaptive system built from very large numbers of mutually interacting subunits (e.g., different professions, departments, equipment). These subunits generate multiple repeated interactions that have the potential to result in rich, collective behaviour that feeds back into the organisation. There is a unique opportunity in New Zealand with the formation of Te Whatu Ora - Health New Zealand and Te Aka Whai Ora - Maori Health Authority and the reorganisation of the healthcare system. This viewpoint is a white paper for the integration of SBL into our healthcare system. We describe our concerns in the current system and list our current capabilities. The way SBL could be implemented in pre- and post-registration phases of practice are explored as well as the integration of communication and culture. Interprofessional education has been shown to improve outcomes and is best done with an interprofessional simulation curriculum. We describe ways that simulation is currently used in our system and describe other uses such as quality improvement, safety and systems engineering and integration. The aim of this viewpoint is to alert Te Whatu Ora and Te Aka Whai Ora of the existing infrastructure of the simulation community in New Zealand and encourage them to invest in its future.


Subject(s)
Delivery of Health Care , Simulation Training , Curriculum , New Zealand
2.
Emerg Med Australas ; 33(2): 255-261, 2021 04.
Article in English | MEDLINE | ID: mdl-32856402

ABSTRACT

OBJECTIVE: Empowering a senior nurse in a shared leadership role has been proposed as a more efficient set up for the cardiac arrest team in ED. In this model, a senior nurse leads the cardiac arrest algorithm which allows cognitive off-loading of the lead emergency physician. The emergency physician is then more available to perform tasks such as echocardiography and exclude reversible causes. Simulation provides an opportunity for training and practice of this shared leadership model. We hypothesised that a structured simulation training programme that focused on implementing a nurse and doctor shared leadership model for cardiopulmonary resuscitation (CPR), would improve leadership and teamwork quality in the setting of cardiac arrest as measured by a Trauma Non-technical Skills (T-NOTECHS) teamwork scale. METHODS: Fifteen senior ED nurses participated in this pre-interventional post-observational study. Training consisted of a didactic course on team leadership and crisis resource management (CRM) followed by 4 × 10-min resuscitation scenarios with a structured debrief focusing on team leadership skills and CRM. The primary outcome was measured on scenarios 1 and 4 using a modified T-NOTECHS teamwork scale. RESULTS: A statistically significant increase in the T-NOTECHS scale was detected for the measures of leadership (P = 0.0028), CRM (P = 0.0001), adherence to New Zealand Resuscitation Council ALS algorithm (P = 0.0088) and situational awareness (P = 0.0002). CONCLUSION: The present study shows that a short simulation training programme improved nurse leadership and teamwork performance in the setting of a shared leadership model for CPR in the ED which could easily be replicated in other departments.


Subject(s)
Cardiopulmonary Resuscitation , Heart Arrest , Simulation Training , Clinical Competence , Emergency Service, Hospital , Humans , Leadership , Patient Care Team , Resuscitation
4.
Cutis ; 102(3): E12-E14, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30372726

ABSTRACT

Acral cutaneous metastasis from internal malignancy is rare, and the pathogenesis is not completely understood. We present the case of a 54-year-old black woman with a history of breast cancer diagnosed 2 years prior who developed multiple cutaneous metastases to acral sites involving the palmar and plantar surfaces of the hands and feet. This case represents an unusual metastatic pattern of breast carcinoma that arose after treatment with bevacizumab, an angiogenesis inhibitor that binds vascular endothelial growth factor A. We propose that bevacizumab-induced vascular changes localized to acral skin may have contributed to the metastatic pattern seen in our patient.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bevacizumab/adverse effects , Breast Neoplasms/drug therapy , Paclitaxel/adverse effects , Skin Neoplasms/secondary , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bevacizumab/therapeutic use , Breast Neoplasms/secondary , Female , Humans , Middle Aged , Paclitaxel/therapeutic use , Skin Neoplasms/chemically induced
5.
JCI Insight ; 3(13)2018 07 12.
Article in English | MEDLINE | ID: mdl-29997301

ABSTRACT

Cytokines play an important role in dysregulated immune responses to infection, pancreatitis, ischemia/reperfusion injury, burns, hemorrhage, cardiopulmonary bypass, trauma, and many other diseases. Moreover, the imbalance between inflammatory and antiinflammatory cytokines can have deleterious effects. Here, we demonstrated highly selective blood-filtering devices - antibody-modified conduits (AMCs) - that selectively eliminate multiple specific deleterious cytokines in vitro. AMCs functionalized with antibodies against human vascular endothelial growth factor A or tumor necrosis factor α (TNF-α) selectively eliminated the target cytokines from human blood in vitro and maintained them in reduced states even in the face of ongoing infusion at supraphysiologic rates. We characterized the variables that determine AMC performance, using anti-human TNF-α AMCs to eliminate recombinant human TNF-α. Finally, we demonstrated selective cytokine elimination in vivo by filtering interleukin 1 ß from rats with lipopolysaccharide-induced hypercytokinemia.


Subject(s)
Antibodies/blood , Antibodies/immunology , Cytokines/blood , Cytokines/immunology , Animals , Humans , Interleukin-1beta , Lipopolysaccharides/pharmacology , Male , Rats , Rats, Sprague-Dawley , Recombinant Proteins , Tumor Necrosis Factor-alpha/blood , Tumor Necrosis Factor-alpha/genetics , Vascular Endothelial Growth Factor A/blood , Vascular Endothelial Growth Factor A/genetics
6.
Memory ; 26(5): 683-690, 2018 05.
Article in English | MEDLINE | ID: mdl-29096586

ABSTRACT

Prior research by Hartwig and Dunlosky [(2012). Study strategies of college students: Are self-testing and scheduling related to achievement? Psychonomic Bulletin & Review, 19(1), 126-134] has demonstrated that beliefs about learning and study strategies endorsed by students are related to academic achievement: higher performing students tend to choose more effective study strategies and are more aware of the benefits of self-testing. We examined whether students' achievement goals, independent of academic achievement, predicted beliefs about learning and endorsement of study strategies. We administered Hartwig and Dunlosky's survey, along with the Achievement Goals Questionnaire [Elliot, A. J., & McGregor, H. A. (2001). A 2 × 2 achievement goal framework. Journal of Personality & Social Psychology, 80, 501-519] to a large undergraduate biology course. Similar to results by Hartwig and Dunlosky, we found that high-performing students (relative to low-performing students) were more likely to endorse self-testing, less likely to cram, and more likely to plan a study schedule ahead of time. Independent of achievement, however, achievement goals were stronger predictors of certain study behaviours. In particular, avoidance goals (e.g., fear of failure) coincided with increased use of cramming and the tendency to be driven by impending deadlines. Results suggest that individual differences in student achievement, as well as the underlying reasons for achievement, are important predictors of students' approaches to studying.


Subject(s)
Academic Success , Goals , Learning , Metacognition , Students/psychology , Adolescent , Adult , Culture , Female , Humans , Male , Middle Aged , Motivation , Young Adult
7.
Cogn Res Princ Implic ; 2(1): 42, 2017.
Article in English | MEDLINE | ID: mdl-29104913

ABSTRACT

Answering questions before a learning episode-"prequestions"-can enhance memory for that information. A number of studies have explored this effect in the laboratory; however, few studies have examined prequestions in a classroom setting. In the current study, the effects of prequestions were examined in an undergraduate course in chemical engineering. At the start of several class meetings, students were provided with a prequestion to answer about the upcoming lesson, and then were asked to provide ratings of confidence in their answers, familiarity with the content in the prequestion, and how much of the assigned reading they had completed. At the end of class, students were given the same question again (postquestion), along with a different question from the same lesson (new question). On a quiz at the end of each week, students were given the postquestions and new questions again, in addition to never-before-seen questions (quiz-only questions) from the same lessons. Performance on questions at the end of class revealed no difference in performance for postquestions vs. new questions. Although weekly quiz performance revealed an effect of retrieval practice-superior memory for material tested at the end of class (postquestions and new questions) compared to material not tested (quiz-only questions)-there was no difference in weekly quiz performance on postquestions vs. new questions. These results suggest that retrieval practice is beneficial to learning in the classroom. However, prequestions do not appear to enhance learning, nor to enhance the effects of retrieval practice.

8.
CBE Life Sci Educ ; 16(2)2017.
Article in English | MEDLINE | ID: mdl-28408408

ABSTRACT

Retrieval practice has been shown to produce significant enhancements in student learning of course information, but the extent to which students make use of retrieval to learn information on their own is unclear. In the current study, students in a large introductory biology course were provided with optional online review questions that could be accessed as Test questions (requiring students to answer the questions before receiving feedback) or as Read questions (providing students with the question and correct answer up-front). Students more often chose to access the questions as Test compared with Read, and students who used the Test questions scored significantly higher on subsequent exams compared with students who used Read questions or did not access the questions at all. Following an in-class presentation of superior exam performance following use of the Test questions, student use of Test questions increased significantly for the remainder of the term. These results suggest that practice questions can be an effective tool for enhancing student achievement in biology and that informing students about performance-based outcomes coincides with increased use of retrieval practice.


Subject(s)
Biology/education , Computer-Assisted Instruction , Educational Measurement/methods , Learning , Students , Feedback , Humans
9.
Ann Biomed Eng ; 45(2): 360-377, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27106636

ABSTRACT

Photocrosslinking hydrogel technologies are attractive for the biofabrication of cardiovascular soft tissues, but 3D printing success is dependent on multiple variables. In this study we systematically test variables associated with photocrosslinking hydrogels (photoinitiator type, photoinitiator concentration, and light intensity) for their effects on encapsulated cells in an extrusion 3D printable mixture of methacrylated gelatin/poly-ethylene glycol diacrylate/alginate (MEGEL/PEGDA3350/alginate). The fabrication conditions that produced desired hydrogel mechanical properties were compared against those that optimize aortic valve or mesenchymal stem cell viability. In the 3D hydrogel culture environment and fabrication setting studied, Irgacure can increase hydrogel stiffness with a lower proportional decrease in encapsulated cell viability compared to VA086. Human adipose derived mesenchymal stem cells (HADMSC) survived increasing photoinitiator concentrations in photo-encapsulation conditions better than aortic valve interstitial cells (HAVIC) and aortic valve sinus smooth muscle cells (HASSMC). Within the range of photo-encapsulation fabrication conditions tested with MEGEL/PEGDA/alginate (0.25-1.0% w/v VA086, 0.025-0.1% w/v Irgacure 2959, and 365 nm light intensity 2-136 mW/cm2), the highest viabilities achieved were 95, 93, and 93% live for HASSMC, HAVIC, and HADMSC respectively. These results identify parameter combinations that optimize cell viability during 3D printing for multiple cell types. These results also indicate that general oxidative stress is higher in photocrosslinking conditions that induce lower cell viability. However, suppressing this increase in intracellular oxidative stress did not improve cell viability, which suggests that other stress mechanisms also contribute.


Subject(s)
Aortic Valve/metabolism , Hydrogels , Mesenchymal Stem Cells/metabolism , Myocytes, Smooth Muscle/metabolism , Printing, Three-Dimensional , Tissue Scaffolds/chemistry , Alginates/chemistry , Alginates/pharmacology , Aortic Valve/cytology , Cell Survival , Cells, Cultured , Gelatin/chemistry , Gelatin/pharmacology , Glucuronic Acid/chemistry , Glucuronic Acid/pharmacology , Hexuronic Acids/chemistry , Hexuronic Acids/pharmacology , Humans , Hydrogels/chemical synthesis , Hydrogels/chemistry , Hydrogels/pharmacology , Materials Testing , Mesenchymal Stem Cells/cytology , Myocytes, Smooth Muscle/cytology , Photochemical Processes , Polyethylene Glycols/chemistry , Polyethylene Glycols/pharmacology
10.
N Z Med J ; 129(1444): 111-114, 2016 Oct 28.
Article in English | MEDLINE | ID: mdl-27806035

ABSTRACT

Ciguatera fish poisoning (CFP) is the most common cause of seafood-toxin poisoning in the world and is most prevalent in tropical and subtropical areas. It causes gastroenteritis but also myriad neurological and cardiovascular symptoms. We present a cluster of CFP that occurred in Wellington Hospital, New Zealand. It resulted in three patients with life threatening cardiotoxicity and a fourth case with severe gastro-intestinal symptoms. The epidemiology, clinical manifestations, diagnosis, treatment and public health issues are discussed.


Subject(s)
Ciguatera Poisoning/epidemiology , Ciguatoxins/analysis , Disease Outbreaks/prevention & control , Gastroenteritis/epidemiology , Adult , Aged , Ciguatera Poisoning/diagnosis , Ciguatera Poisoning/drug therapy , Diuretics, Osmotic/administration & dosage , Female , Gastroenteritis/etiology , Humans , Male , Mannitol/administration & dosage , Middle Aged , New Zealand/epidemiology , Public Health/standards
11.
Nano Lett ; 15(10): 6332-8, 2015 Oct 14.
Article in English | MEDLINE | ID: mdl-26158690

ABSTRACT

High-efficiency upconverted light would be a desirable stimulus for triggered drug delivery. Here we present a general strategy to achieve photoreactions based on triplet-triplet annihilation upconversion (TTA-UC) and Förster resonance energy transfer (FRET). We designed PLA-PEG micellar nanoparticles containing in their cores hydrophobic photosensitizer and annihilator molecules which, when stimulated with green light, would undergo TTA-UC. The upconverted energy was then transferred by FRET to a hydrophobic photocleavable group (DEACM), also in the core. The DEACM was bonded to (and thus inactivated) the cell-binding peptide cyclo-(RGDfK), which was bound to the PLA-PEG chain. Cleavage of DEACM by FRET reactivated the PLA-PEG-bound peptide and allowed it to move from the particle core to the surface. TTA-UC followed by FRET allowed photocontrolled binding of cell adhesion with green light LED irradiation at low irradiance for short periods. These are attractive properties in phototriggered systems.


Subject(s)
Light , Nanoparticles , Fluorescence Resonance Energy Transfer , Peptides, Cyclic/chemistry , Proton Magnetic Resonance Spectroscopy
12.
Exp Brain Res ; 233(6): 1825-35, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25827332

ABSTRACT

Genetically engineered mice are valuable models for elucidation of auditory and vestibular pathology. Our goal was to establish a comprehensive vestibular function testing system in mice using: (1) horizontal angular vestibulo-ocular reflex (hVOR) to evaluate semicircular canal function and (2) otolith-ocular reflex (OOR) to evaluate otolith organ function and to validate the system by characterizing mice with vestibular dysfunction. We used pseudo off-vertical axis rotation to induce an otolith-only stimulus using a custom-made centrifuge. For the OOR, horizontal slow-phase eye velocity and vertical eye position were evaluated as a function of acceleration. Using this system, we characterized hVOR and OOR in the caspase-3 (Casp3) mutant mice. Casp3 (-/-) mice had severely impaired hVOR gain, while Casp3 (+/-) mice had an intermediate response compared to WT mice. Evaluation of OOR revealed that at low-to-mid frequencies and stimulus intensity, Casp3 mutants and WT mice had similar responses. At higher frequencies and stimulus intensity, the Casp3 mutants displayed mildly reduced otolith organ-related responses. These findings suggest that the Casp3 gene is important for the proper function of the semicircular canals but less important for the otolith organ function.


Subject(s)
Caspase 3/deficiency , Nystagmus, Pathologic/genetics , Nystagmus, Pathologic/pathology , Otolithic Membrane/physiology , Reflex, Vestibulo-Ocular/genetics , Semicircular Canals/physiopathology , Acceleration , Analysis of Variance , Animals , Apoptotic Protease-Activating Factor 1/genetics , Apoptotic Protease-Activating Factor 1/metabolism , Biomechanical Phenomena , Caspase 3/genetics , Female , Head Movements/physiology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Mutation/genetics , Rotation , Vestibular Function Tests
13.
N Z Med J ; 128(1425): 34-42, 2015 Nov 20.
Article in English | MEDLINE | ID: mdl-26905985

ABSTRACT

AIM: To investigate the effects on lung function of IV magnesium in acute exacerbations of COPD (AECOPD), when given in conjunction with standard bronchodilator therapy. METHODS: This was a pilot study to a randomised, double-blinded, placebo-controlled trial. 30 patients presenting to ED with AECOPD were included. In addition to standard bronchodilator therapy, 17 patients were given saline, and 13 received 2 g of magnesium sulphate intravenously. Spirometry was carried out at presentation (TA), after initial standard bronchodilator therapy (TB) and immediately (T0), at 60 minutes (T60) and 120 minutes (T120) after trial drug infusion. Primary outcomes were percentage change in FEV1 and FVC at T0, T60 and T120. Secondary outcomes were admission rates, length of stay and requirement for NIV or mechanical ventilation. Trial registration (ANZCTR), ACTRN12613000837729. RESULTS: Greater improvements were seen in FEV1 at T0, T60 and T120 compared to TB in magnesium group (at T120, mean percentage change in FEV1 was 27.07% with magnesium versus 11.39% in the placebo group, 95%CI 3.7 to 27.7, p=0.01). Similar significantly greater improvements were noted with FVC in the magnesium group, compared to TB. CONCLUSIONS: IV magnesium sulphate used as an adjunct therapy to standard bronchodilators in AECOPD presenting to ED may improve lung function in the short term.


Subject(s)
Bronchodilator Agents/therapeutic use , Glucocorticoids/therapeutic use , Magnesium Sulfate/therapeutic use , Oxygen Inhalation Therapy , Pulmonary Disease, Chronic Obstructive/therapy , Administration, Inhalation , Administration, Intravenous , Aged , Aged, 80 and over , Albuterol/therapeutic use , Disease Progression , Double-Blind Method , Drug Therapy, Combination , Female , Forced Expiratory Volume , Humans , Hydrocortisone/therapeutic use , Ipratropium/therapeutic use , Male , Middle Aged , Pilot Projects , Prednisone/therapeutic use , Pulmonary Disease, Chronic Obstructive/physiopathology , Vital Capacity
14.
Clin Lymphoma Myeloma Leuk ; 14(6): 518-24, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25442486

ABSTRACT

BACKGROUND: The purpose of this study was to determine the prevalence of vitamin D deficiency in CTCL patients and whether supplementation corrects vitamin D deficiency or treatment outcome. PATIENTS AND METHODS: Three hundred eleven CTCL patients including 27/311 (8.7%) with Sézary syndrome (SS), 169 cancer controls, and 69 normal controls from the M.D. Anderson clinics had 25(OH)D3 levels determined and categorized as deficient (< 20 ng/mL),insufficient (20-29 ng/mL), or sufficient (≥ 30 ng/mL). Clinical response was determined according to a change in percent body surface area involvement. RESULTS: Low 25(OH)D3 (< 30 ng/mL) levels were present in 76.9% of mycosis fungoides/SS patients, 75.2% of cancer controls, and 66.7% of healthy controls (P » .05, .07) and in 30% to 39% of historical normal controls. Correction of deficiency was successful in 35% or 55 of 156 patients who were given dealer's choice of either vitamin D2 at 50,000 IU orally (p.o.) biweekly or D3 1000 IU p.o. daily. Correction of vitamin D levels was noted in 27 of 100 (27%) patients given D3 and 28 of 56 (50%) given D2. Responses to standard CTCL therapy was similar among patients with corrected and persistently low levels (P » .51). CONCLUSION: To our knowledge,this is the first study of vitamin D status in CTCL patients. Vitamin D deficiency was present in CTCL and other cancer patients compared with normal and historical controls. Correction of vitamin D deficiency and type of vitamin D supplementation used did not affect the overall clinical disease response.


Subject(s)
Mycosis Fungoides/complications , Neoplasms/complications , Sezary Syndrome/complications , Vitamin D Deficiency/complications , Adult , Aged , Case-Control Studies , Dietary Supplements , Female , Humans , Male , Middle Aged , Mycosis Fungoides/diagnosis , Mycosis Fungoides/therapy , Neoplasm Staging , Neoplasms/diagnosis , Neoplasms/therapy , Sezary Syndrome/diagnosis , Sezary Syndrome/therapy , Treatment Outcome , Vitamin D/administration & dosage , Vitamin D/blood , Vitamin D Deficiency/diagnosis , Vitamin D Deficiency/drug therapy , Young Adult
16.
Skeletal Radiol ; 42(9): 1225-33, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23715887

ABSTRACT

PURPOSE: Indirect magnetic resonance arthrography (I-MRA) confers significant logistical advantages over direct MRA and does not require articular injection. In this study, we determined the diagnostic performance of I-MRA in relation to conventional MRI and arthroscopy or surgery in detecting tears of the glenoid labrum, including Bankart lesions and superior labral antero-posterior (SLAP) tears in a standard clinical setting. PATIENTS AND METHODS: Ninety-one symptomatic patients underwent conventional MRI and I-MRA of the affected shoulder, followed by either arthroscopy or open surgery. The scans were interpreted independently by two experienced radiology consultants with a special interest in musculoskeletal radiology. Using the surgical findings as the standard of reference, sensitivity, specificity, and diagnostic accuracy of conventional non-contrast MRI and I-MRA in the detection of labral tears were calculated. RESULTS: The sensitivity of I-MRA was 95 and 97 %, respectively, for two radiologists as opposed to 79 and 83 % for conventional MRI. For both radiologists, the specificity of I-MRA, as well as MRI, was 91 % for detection of labral tears of all types. Accuracy of diagnosis was 93 and 95 %, respectively, for two radiologists with indirect MRA, compared to 84 and 86 % with non-contrast MRI. CONCLUSIONS: This retrospective study shows that I-MRA is a highly accurate and sensitive method for the detection of labral tears. The data obtained supports the use of I-MRA as standard practice in patients with shoulder instability due to suspected labral pathology where further investigative imaging is indicated.


Subject(s)
Fibrocartilage/injuries , Fibrocartilage/pathology , Magnetic Resonance Imaging/methods , Shoulder Injuries , Shoulder Joint/pathology , Adult , Aged , Female , Humans , Male , Middle Aged , Reproducibility of Results , Rupture/pathology , Sensitivity and Specificity
17.
J Couns Psychol ; 60(2): 303-310, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23458605

ABSTRACT

Researchers have found that the stigma associated with seeking therapy--particularly self-stigma--can inhibit the use of psychological services. Yet, most of the research on self-stigma has been conducted in the United States. This is a considerable limitation, as the role of self-stigma in the help-seeking process may vary across cultural groups. However, to examine cross-cultural variations, researchers must first develop culturally valid scales. Therefore, this study examined scale validity and reliability of the widely used Self-Stigma of Seeking Help scale (SSOSH; Vogel, Wade, & Haake, 2006) across samples from 6 different countries (England, Greece, Israel, Taiwan, Turkey, and the United States). Specifically, we used a confirmatory factor analysis framework to conduct measurement invariance analysis and latent mean comparisons of the SSOSH across the 6 sampled countries. Overall, the results suggested that the SSOSH has a similar univariate structure across countries and is sufficiently invariant across countries to be used to explore cultural differences in the way that self-stigma relates to help-seeking behavior.


Subject(s)
Counseling , Cross-Cultural Comparison , Patient Acceptance of Health Care/psychology , Self Concept , Social Stigma , Surveys and Questionnaires , Adolescent , Adult , Cultural Characteristics , Female , Humans , Male , Middle Aged , Psychometrics/statistics & numerical data , Reproducibility of Results , Young Adult
18.
Biomaterials ; 33(32): 8026-33, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22898181

ABSTRACT

Tissue engineering-based approaches have the potential to improve stem cell engraftment by increasing cell delivery to the myocardium. Our objective was to develop and characterize a naturally-derived, autologous, biodegradable hydrogel in order to improve acute stem cell retention in the myocardium. HA-blood hydrogels (HA-BL) were synthesized by mixing in a 1:1(v/v) ratio, lysed whole blood and hyaluronic acid (HA), whose carboxyl groups were functionalized with N-hydroxysuccinimide (NHS) to yield HA succinimidyl succinate (HA-NHS). We performed physical characterization and measured survival/proliferation of cardiosphere-derived cells (CDCs) encapsulated in the hydrogels. Hydrogels were injected intra-myocardially or applied epicardially in rats. NHS-activated carboxyl groups in HA react with primary amines present in blood and myocardium to form amide bonds, resulting in a 3D hydrogel bound to tissue. HA-blood hydrogels had a gelation time of 58±12 s, swelling ratio of 10±0.5, compressive and elastic modulus of 14±3 and 1.75±0.6 kPa respectively. These hydrogels were not degraded at 4 wks by hydrolysis alone. CDC encapsulation promoted their survival and proliferation. Intra-myocardial injection of CDCs encapsulated in these hydrogels greatly increased acute myocardial retention (p=0.001). Epicardial application of HA-blood hydrogels improved left ventricular ejection fraction following myocardial infarction (p=0.01). HA-blood hydrogels are highly adhesive, biodegradable, promote CDC survival and increase cardiac function following epicardial application after myocardial infarction.


Subject(s)
Blood Cells/chemistry , Hyaluronic Acid/chemistry , Hydrogels/chemistry , Myocardium/cytology , Plasma/chemistry , Stem Cell Transplantation , Tissue Scaffolds/chemistry , Animals , Blood Cells/metabolism , Cell Proliferation , Cell Survival , Cells, Cultured , Elastic Modulus , Female , Humans , Hyaluronic Acid/metabolism , Hydrogels/metabolism , Male , Myocardial Infarction/pathology , Myocardial Infarction/surgery , Myocardium/pathology , Plasma/metabolism , Rats , Rats, Inbred WKY , Rats, Nude , Succinimides/chemistry
19.
J Arthroplasty ; 27(3): 331-40, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21944371

ABSTRACT

A tourniquet is often used in total knee arthroplasty resulting in improved visualization of structures, reduced intraoperative bleeding and better cementation. The risks include deep vein thrombosis and pulmonary embolism. To quantify the case for or against tourniquet use, we carried out a systematic review and meta-analysis of selected randomized controlled trials. Ten studies were included in the meta-analysis. Of the 8 outcomes analyzed (surgery duration; total, intraoperative, and postoperative blood losses; deep vein thrombosis; pulmonary embolism; and minor/major complications), the total and intraoperative blood losses were less using a tourniquet. Minor complications were more common in the tourniquet group. The remaining outcomes showed no difference between the groups. Using a tourniquet may be beneficial, but long-term studies of outcome are needed.


Subject(s)
Arthroplasty, Replacement, Knee/methods , Tourniquets , Humans , Randomized Controlled Trials as Topic , Treatment Outcome
20.
BMC Neurosci ; 12: 102, 2011 Oct 12.
Article in English | MEDLINE | ID: mdl-21988729

ABSTRACT

BACKGROUND: Caspase-3 is one of the most downstream enzymes activated in the apoptotic pathway. In caspase-3 deficient mice, loss of cochlear hair cells and spiral ganglion cells coincide closely with hearing loss. In contrast with the auditory system, details of the vestibular phenotype have not been characterized. Here we report the vestibular phenotype and inner ear anatomy in the caspase-3 deficient (Casp3(-/-)) mouse strain. RESULTS: Average ABR thresholds of Casp3(-/-) mice were significantly elevated (P < 0.05) compared to Casp3(+/-) mice and Casp3(+/+) mice at 3 months of age. In DPOAE testing, distortion product 2F1-F2 was significantly decreased (P < 0.05) in Casp3(-/-) mice, whereas Casp3(+/-) and Casp3(+/+) mice showed normal and comparable values to each other. Casp3(-/-) mice were hyperactive and exhibited circling behavior when excited. In lateral canal VOR testing, Casp3(-/-) mice had minimal response to any of the stimuli tested, whereas Casp3(+/-) mice had an intermediate response compared to Casp3(+/+) mice. Inner ear anatomical and histological analysis revealed gross hypomorphism of the vestibular organs, in which the main site was the anterior semicircular canal. Hair cell numbers in the anterior- and lateral crista, and utricle were significantly smaller in Casp3(-/-) mice whereas the Casp3(+/-) and Casp3(+/+) mice had normal hair cell numbers. CONCLUSIONS: These results indicate that caspase-3 is essential for correct functioning of the cochlea as well as normal development and function of the vestibule.


Subject(s)
Caspase 3/deficiency , Ear, Inner/enzymology , Ear, Inner/physiopathology , Vestibular Diseases/enzymology , Vestibular Diseases/physiopathology , Animals , Behavior, Animal/physiology , Caspase 3/genetics , Disease Models, Animal , Mice , Mice, Inbred C57BL , Mice, Knockout , Phenotype , Vestibular Diseases/genetics , Vestibule, Labyrinth/enzymology , Vestibule, Labyrinth/metabolism , Vestibule, Labyrinth/physiopathology
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