Effect of a combination of general anesthesia and superficial cervical plexus block with ropivacaine on patients undergoing thyroidectomy

Purpose: To investigate the effect of a combination of general anesthesia and superficial cervical plexus block (SCPB) with ropivacaine on patients undergoing thyroidectomy. Methods: Ninety-six (96) patients undergoing thyroidectomy were randomly divided into control and study group. Both groups were subjected to SCPB in combination with general anesthesia. Ropivacaine was used for SCPB in the study group. Vital signs, visual analogue scale (VAS) scores, and serum interleukin 1β (IL-1β) levels were determined at various time points (T) after tracheal intubation. Occurrence of adverse reactions was recorded. Results: Compared with the control group, mean arterial pressure (MAP), heart rate (HR), diastolic blood pressure (DBP), and systolic blood pressure (SBP) levels from T1 to T5 were declined in study group (p < 0.01). VAS scores of study group were significantly lower at 12, 24, and 48 h after thyroidectomy than in control group (p < 0.05). At 5, 10 and 15 h after surgery, serum IL-1β level in study group was down-regulated (p < 0.05). Moreover, a marked decrease in the incidence of adverse reactions was also found in the study group post-surgery (p < 0.05). Conclusion: Ropivacaine is effective for SCPB in combination with general anesthesia in patients undergoing thyroidectomy. It is safer and more feasible in SCPB when combined with general anesthesia. However, further clinical trials are required to validate this technique

Design and Characterization of a Human Monoclonal Antibody that Modulates Mutant Connexin 26 Hemichannels Implicated in Deafness and Skin Disorders

Background: Mutations leading to changes in properties, regulation, or expression of connexin-made channels have been implicated in 28 distinct human hereditary diseases. Eight of these result from variants of connexin 26 (Cx26), a protein critically involved in cell-cell signaling in the inner ear and skin. Lack of non-toxic drugs with defined mechanisms of action poses a serious obstacle to therapeutic interventions for diseases caused by mutant connexins. In particular, molecules that specifically modulate connexin hemichannel function without affecting gap junction channels are considered of primary importance for the study of connexin hemichannel role in physiological as well as pathological conditions. Monoclonal antibodies developed in the last three decades have become the most important class of therapeutic biologicals. Recombinant methods permit rapid selection and improvement of monoclonal antibodies from libraries with large diversity.Methods: By screening a combinatorial library of human single-chain fragment variable (scFv) antibodies expressed in phage, we identified a candidate that binds an extracellular epitope of Cx26. We characterized antibody action using a variety of biochemical and biophysical assays in HeLa cells, organotypic cultures of mouse cochlea and human keratinocyte-derived cells.Results: We determined that the antibody is a remarkably efficient, non-toxic, and completely reversible inhibitor of hemichannels formed by connexin 26 and does not affect direct cell-cell communication via gap junction channels. Importantly, we also demonstrate that the antibody efficiently inhibits hyperative mutant Cx26 hemichannels implicated in autosomal dominant non-syndromic hearing impairment accompanied by keratitis and hystrix-like ichthyosis-deafness (KID/HID) syndrome. We solved the crystal structure of the antibody, identified residues that are critical for binding and used molecular dynamics to uncover its mechanism of action.Conclusions: Although further studies will be necessary to validate the effect of the antibody in vivo, the methodology described here can be extended to select antibodies against hemichannels composed by other connexin isoforms and, consequently, to target other pathologies associated with hyperactive hemichannels. Our study highlights the potential of this approach and identifies connexins as therapeutic targets addressable by screening phage display libraries expressing human randomized antibodies

Experimental study on effect of inclination angles to ammonia pulsating heat pipe

In this paper, a novel study on performance of closed loop pulsating heat pipe (CLPHP) using ammonia as working fluid is experimented. The tested CLPHP, consisting of six turns, is fully made of quartz glass tubes with 6 mm outer diameter and 2 mm inner diameter. The filling ratio is 50%. The visualization investigation is conducted to observe the oscillation and circulation flow in the CLPHP. In order to investigate the effects of inclination angles to thermal performance in the ammonia CLPHP, four case tests are studied. The trends of temperature fluctuation and thermal resistance as the input power increases at different inclination angles are highlighted. The results show that it is very easy to start up and circulate for the ammonia CLPHP at an inclining angle. The thermal resistance is low to 0.02 K/W, presenting that heat fluxes can be transferred from heating section to cooling section very quickly. It is found that the thermal resistance decreases as the inclination angle increases. At the horizontal operation, the ammonia CLPHP can be easy to start up at low input power, but hard to circulate. In this case, once the input power is high, the capillary tube in heating section will be burnt out, leading to worse thermal performance with high thermal resistance

Model-Based Learning Controls And Their Comparisons Using Lyapunov Direct Method

Model-based learning control of nonlinear systems is studied. Two types of learning algorithms, described by differential equations and/or difference equations to learn unknown time functions, are designed and compared using the Lyapunov\u27s direct method. The time functions to be learned are classified into several classes according to their properties such as continuity, periodicity, and value at the origin of the state space. Conditions are found for iterative learning controls to achieve asymptotic stability and asymptotic learning convergence. For a comparative study, learning capability of a control is defined and, using the criterion, other model-based controls with learning capability such as adaptive controls and robust controls are investigated. Through the study, iterative learning control is shown to be the one best suited for learning unknown time functions of known period. Finally it is shown for the first time that an iterative learning control is directly applicable to systems described by nonlinear partial differential equation

Full visualization and startup performance of an ammonia pulsating heat pipe

In this paper, a novel study on full visualization and startup performances of pulsating heat pipe using ammonia as working fluid are experimented. The tested pulsating heat pipe, consisting of 6 turns, is fully made of quartz glass tubes with 6 mm outer diameter and 2 mm inner diameter. The filling ratio is 70%. Wall temperature fluctuations of several key positions are recorded under a series charge of heat inputs. The visualization investigation is conducted to observe the oscillations and circulation flows with the advantage of high quality digital video camera, by which the unique thermodynamic behaviors are able to recognize and analyze more easily. The experimental results show that the startup power required by the ammonia Pulsating Heat Pipe (PHP) is very small, owing to particular identities of ammonia. It is observed that there are also some unevenly distributions in slug-train during initial and operating state. Phenomena such as circulation flows and local oscillations coupling breaking up of bubbles and formation of slugs are observed

Design of Radial Flow Channel Proton Exchange Membrane Fuel Cell Based on Topology Optimization

In this paper, the flow channel of the radial proton exchange membrane fuel cell (PEMFC) is optimized by the topological optimization method. Using the SNOPT algorithm, a two-dimensional stable constant temperature model is freely constructed in the cyclic sector design domain. Topology optimization aims to maximize the efficiency of PEMFC and minimize the energy dissipation of reaction gas. We analyze radial topology flow channels’ mass transfer capacity and cell performance with different maximum volume constraints. The results show that under high current density, the performance of the optimized channel is significantly better than that of the traditional channel. Increasing the maximum volume constraint is beneficial for improving the mass transfer of PEMFC. At 0.6 V, the cell performance of Scheme 4 is 14.9% higher than the serpentine flow channel and 9.5% higher than the parallel flow channel. In addition, in the optimal selection, 3D simulation modeling is carried out for more accurate verification

Fully human antibody specifically inhibiting connexin 26

(EN)Disclosed is a fully human antibody specifically inhibiting a connexin 26. The antibody is a recombinant immunoglobulin having the structure of scFv-Fc. scFv refers to a single-chain antibody comprising a heavy chain variable region and a light chain variable region, wherein the amino acid sequence of the heavy chain variable region is set forth in SEQ ID NO: 1 and the amino acid sequence of the light chain variable region is set forth in SEQ ID NO: 2. Fc refers to a constant region. An amino acid sequence from the 41st to the 56th amino acids in an extracellular region of human connexin 26, i.e., KEVWGDEQADFVCNTL, is used as an antigen. The invention is obtained by employing a single-chain antibody phage display library and a screening technique. A biochemical analysis and an immunofluorescent identification of the antibody indicated that the antibody specifically recognizes the connexin 26 and inhibits an activity of a hemichannel formed by the connexin 26. An animal test showed that the antibody exerted a significant inhibitory effect on the activity of a hemichannel in a murine cochlear tissue slice. Therefore, the antibody can be used for the treatment of a disease associated with connexin mutation. (FR)La pr\ue9sente invention concerne un anticorps enti\ue8rement humain inhibant en particulier une connexine 26. L'anticorps est une immunoglobuline recombin\ue9e poss\ue9dant la structure de scFv-Fc. scFv d\ue9signe un anticorps monocat\ue9naire comprenant une r\ue9gion variable de cha\ueene lourde et une r\ue9gion variable de cha\ueene l\ue9g\ue8re, la s\ue9quence d'acides amin\ue9s de la r\ue9gion variable de cha\ueene lourde \ue9tant pr\ue9sent\ue9e dans SEQ ID NO: 1 et la s\ue9quence d'acides amin\ue9s de la r\ue9gion variable de cha\ueene l\ue9g\ue8re \ue9tant pr\ue9sent\ue9e dans SEQ ID NO: 2. Fc d\ue9signe une r\ue9gion constante. Une s\ue9quence d'acides amin\ue9s entre le 41\ue8me et le 56\ue8me acide amin\ue9 dans une r\ue9gion extracellulaire de la connexine 26 humaine, c'est-\ue0-dire, KEVWGDEQADFVCNTL, est utilis\ue9e comme antig\ue8ne. L'invention est obtenue par l'utilisation d'une banque d'expression phagique d'anticorps monocat\ue9naires et d'une technique de criblage. Une analyse biochimique et une identification par immunofluorescence de l'anticorps ont indiqu\ue9 que l'anticorps reconna\ueet sp\ue9cifiquement la connexine 26 et inhibe une activit\ue9 d'un demi-canal form\ue9 par la connexine 26. Une exp\ue9rience sur des animaux a montr\ue9 que l'anticorps exer\ue7ait un effet inhibiteur notable sur l'activit\ue9 d'un demi-canal dans une lamelle de tissu cochl\ue9aire murin. Par cons\ue9quent, l'anticorps peut \ueatre utilis\ue9 dans le traitement d'une maladie associ\ue9e \ue0 une mutation de la connexin