1,721,041 research outputs found
Biomechanical evaluation of an absorbable fixation strap for use in total laparoscopic gastropexy in dogs
No full textOBJECTIVE To compare load-to-failure results for laparoscopic absorbable fixation straps (AFSs) deployed at various angles and for AFSs versus absorbable knotless (barbed) suture when used in simulated total laparoscopic gastro-pexy (TLG) in specimens from cadaveric dogs. SAMPLE 30 stomach and abdominal body wall specimens. PROCEDURES Specimens were assigned to 1 of 3 groups for use in simulated TLG con-structs for comparisons of load-to-failure results for single AFSs deployed at 30°, 60°, or 90° (AFS-angle group; n = 10) or for a gastropexy span of 4 to 5 cm achieved with 3-0 absorbable knotless (barbed) monofilament suture applied in a simple continuous pattern (TLG-1; 10) versus 8 AFSs applied with a deployment angle > 30° (TLG-2; 10). A 1-way ANOVA was used to compare results among AFS deployment angles (30°, 60°, or 90°) and between TLG-1 and TLG-2. RESULTS Mean ± SD load to failure for the AFS-angle group was significantly higher for the AFS deployment angles of 60° (8.00 ± 3.90 N) and 90° (12.71 ± 8.00 N), compared with 30° (5.17 ± 1.90 N). However, no substantial difference was detected in the mean ± SD load to failure for TLG-1 (39.18 ± 7.1 N) versus TLG-2 (31.43 ± 10.86 N). CONCLUSIONS AND CLINICAL RELEVANCE Results of the present study supported the potential use of AFSs in gastro-pexy in dogs; however, prospective clinical research with adequate long-term follow-up is warranted before recommendations can be made
Survival of bone marrow mesenchymal stem cells labelled with red fluorescent protein in an ovine model of collagenase-induced tendinitis
Full text linkObjective: The aim of this study was to track the survival and efficacy of allogeneic bone marrow mesenchymal stem cells (BM-MSC) marked with red fluorescent protein (BM-MSCRFP) in an ovine model of collagenase-induced tendinopathy. Methods: Bone marrow was harvested from one donor sheep and BM-MSC were isolated, cultivated and transfected with red fluorescent protein (BM-MSCRFP). Collagenase was injected into both Achilles tendons in the remaining nine sheep. After two weeks the left tendon was injected with a solution of 6 x 106 BM-MSCRFP and fibrin glue, while only fibrin glue was administered to the contra-lateral tendon in each sheep. After three, four and six weeks the tendons were harvested and evaluated for morphology, collagen I deposition, presence of CD34+ cells, and fluorescent labelled BM-MSC. Results: We demonstrated that delivery of BM-MSC into tendon lesions had positive effects on the injured tendons. The BM-MSCRFP survived at three, four and six weeks after treatment, leading to better quality healing of tendons as compared to the controls, where no labelled cells were detected. Interestingly, we demonstrated high expression of CD34+ cells in tendons that had been treated with BM-MSCRFP. Clinical relevance: Mesenchymal stem cell allografts have a positive effect on tendon healing and local injection of BM-MSC directly into the tendon allows the homing of BM-MSC for good efficiency of engraftment
Ex-Vivo Evaluation of “First Tip Closing” Radiofrequency Vessel Sealing Devices for Swine Small Intestinal Transection
No full textThis study compared burst pressure (BP), number of activations, and histological assessment of ex vivo swine small intestine loops transected by stapler, a single fulcrum radiofrequency vessel sealing (RFVS) device, and the newly-developed jaws RFVS. Fifty (n = 50) 20 cm long jejunal loops were randomly assigned to be transected with RFVS devices and linear stapler (Caiman5, Caiman Maryland, Caiman12, Ligasure Atlas, and Stapler group as control respectively). Caiman5, Caiman12 and stapler required only one activation to complete the sealing. The mean BP in Caiman5 and Caiman Maryland groups were significantly lower (p < 0.05) than the S group as control and the other RFVS devices studied. RFVS Caiman12 and Ligasure Atlas produced mean BP values that were close to the Control and did not differ between them. The lumen was totally closed in the Caiman12 and Ligasure Atlas groups. The findings of this investigation were promising; we discovered that Caiman12 and Ligasure Atlas produce comparable mechanical capabilities as well as stapled intestinal closure, however Caiman12 need a single activation to complete the transection
“Aspetti ecografici e tomografici in un gatto affetto da grave insufficienza epatica secondaria a carcinoma tiroideo”
No full textInfluence of abdominal surgery on pulmonary atelectasis formation in dogs
No full textThe aim of this study was to evaluate the influence of abdominal surgery on atelectasis formation in healthy dogs. After the induction of general anesthesia (GA), 20 dogs, scheduled for elective ovariohysterectomy, were positioned in dorsal recumbency: 10 dogs underwent immediate surgery (S group), while 10 dogs (NS group) were maintained under anesthesia for 60 min before surgery. In both groups, a helical computed tomography (CT) scan of the thorax and an arterial blood gas analysis were performed 60 min after the induction of GA. Lung aeration was estimated by analyzing the radiographic attenuation of the CT images. The atelectasic and poorly aerated lung compartments were significantly larger, and the normally aerated lung compartment was smaller in the S group compared to the NS group. The PaO2 was similar in both groups. Abdominal surgery significantly increases pulmonary atelectasis in healthy dogs under GA
COMPARISON BETWEEN OXYGEN INDICES AND COMPUTED TOMOGRAPHY (CT) FOR EVALUATION OF ATELECTASIS IN DOGS
No full textObjective - To evaluate arterial blood gas indices in dogs with and without pulmonary atelectasis.
Methods - Retrospective study conducted on dogs anesthetized for pulmonary computed tomography (CT) scan; inclusion criteria were the presence of normal arterial blood gas analysis before anesthesia (T0), a blood gas analysis during or immediately after the pulmonary scan (T1), and the absence of cardiopulmonary alterations revealed by CT. On the basis of pulmonary density with the region of interest (ROI), animals were divided into groups with atelectasis (GA), in which at least one evaluated area showed values between −100 and −500 HU, and without atelectasis (GNA) with all evaluated areas lower than −500. PaO2/FiO2, P[A-a]O2 gradient, dead-space/tidal volume ratio (Vd/Vt = [PaCO2 − EtCO2] / PaCO2) and the F-Shunt ([(CcO2 − CaO2) / (CcO2 − CaO2 + 3.5 mL/dL)] × 100 were calculated. A Kolmogorov–Smirnov test was used to evaluate the distribution of data, expressed as mean ± standard deviation and a Student t-test for unpaired values was used to compare results. P-value < 0.05 was considered significant.
Results - Thirty-six animals met the inclusion criteria: 21 in GNA and 15 in GA. P[A-a]O2 gradient measured prior to anesthesia was 6.4 ± 4.3 mm Hg in GNA and 9 ± 4 mm Hg in GA. Mean ROI value was −542 ± 72 HU in GA and −666 ± 22 HU in GNA. Vd/Vt at T1 resulted 0.42 ± 0.03 for GNA and 0.45 ± 0.07 for GA. PaO2/FiO2 was significantly higher in GNA at T1 versus T0 (474 ± 27 mm Hg vs. 545 ± 41 mm Hg); no differences were detected in GA [452 ± 77 mm Hg (T0) vs. 491 ± 52 mm Hg (T1)] or between the 2 groups. A significant increase in F-shunt during anesthesia occurred in both GA [−2 ± 4.6% (T0) and 28.2 ± 4.3% (T1)] and GNA [−1 ± 4.4% (T0) and 11.40 ± 3.9% (T1)].
Conclusion: F-shunt, calculated on arterial blood samples, may be a sensitive and useful index to detect pulmonary shunt due to atelectasis. Further studies are needed to verify how this index changes in patients with contextual pulmonary alterations
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Cardiovascular effects of continuous positive airway pressure (CPAP) in dogs under anesthesiaassessed by Doppler echocardiography
No full textGeneral anesthesia impairs respiratory functionby the development of atelectasis in association with alteredventilation at pulmonary bases1. Applying Continuous Positive Airways Pressure (CPAP) in spontaneously breathing patients reduce the work of breathing, increases functional residualcapacity and is often recommended to prevent orreduce alveolar collapse1. In human medicine it has been widely recognized that an increase in intra-thoracic pressure is associated with a decrease in cardiac outputbecause of the reduction of venous return2. Nevertheless, conflictingresults (increases, decreases, or no change) in CO have beenreported and it was studied that the effects of CPAP on cardiac function were influenced by increasing CPAP levels. Doppler echocardiography represents a way to investigate how cardiac parameters can be affected and can change during CPAP application. What about CPAP application and its cardiovascular consequences in dogs?
Aim of the study
The aim of this study is to investigate by Doppler echocardiographythe cardiovascular effects of a low level of CPAP(5 cm H2O) in dogs under anesthesia.
Materials and Methods
20 dogs have been enrolled in the study and divided into two groups. Both groups underwent anesthesia with a standard protocol and in Group A (10 dogs) CPAP was administered (5 cmH2O). Group B (10 dogs) served as control group and did not receive CPAP. Cardiovascular parameters (heart rate, mean arterial pressure and echocardiographic indices) were registered before (T0) and 15 minutes after anesthesia induction (T1), during anesthesia with or without CPAP(T2) and during recovery (T3).All patients were anesthetizedwith acepromazine (20 μg/kg), morphine (0.3 mg/kg), propofol (4 mg/kg) and isoflurane (end-tidal concentration 1.3 %)in spontaneous ventilation. Standard echocardiography (Esaote ultrasound system MyLab30) was performed usinga 2.5 MHz transducer. The following parameters were calculated as indicators of cardiovascular function: ejection fraction (EF%), left and right cardiac index (CI), left ventricle end diastolic volume index (LV-EDVI ml/m2), ratio of isovolumetric contraction time to ejection time (IVCT/ET), ratio of early rapid filling peak to atrial peak filling of transatrioventricular inflow (E/A), time velocity integral of atrioventricular inflow (TVI), aortic max velocity (AoVmax) and pulmonary max velocity (P Vmax).
Results and Conclusions
On the whole no statistical differences have been revealed in cardiovascular parameters at T2 compared to T1 in both groups.Interestingly a significant difference was revealed in EF between CPAP group and control group at T2. Myocardial diastolic properties remained unchanged. The right cardiac index do not change.Results of this study suggest not only that application of low levels of CPAP during anesthesia of healthy dogs does not negatively affect cardiac function and hemodynamic parameters, but also that it could positivelyinfluence the global left ventricular systolic function. In conclusion the application of this level of CPAP during anesthesia in healthy dogs could be considered safe.
References
1Russo et al, 2013. J. CLIN. ANESTH. 25, 314-320.2Huemer et al, 1994. CHEST 106, 67-7
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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