Name: using q suture to enhance resistance to gap formation and tensile strength of repaired flexor tendons
Uploaded: 2020-06-03T15:00:00
Description: Watch this Scientific Journal Video about Using Q Suture to Enhance Resistance to Gap Formation and Tensile Strength of Repaired Flexor Tendons at JoVE.com

The authors acknowledge support from Graduate Research Innovation Project of Jiangsu Province (YKC16061).

All experimental procedures described were approved by the Administration Committee of Experimental Animals of the Nantong University. Thirty porcine tendons were repaired with three 2-strand repairs: 2-strand core suture, 2-strand core suture plus 2Q, and 2-strand core suture plus running peripheral sutures. The other 30 porcine tendons were repaired with three 4 strand repairs: 4-strand core suture, 4-strand core suture plus 2Q, and 4-strand core suture plus running peripheral sutures.
1. Prep...

<ol>
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F., Wu, Y. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+a+Q+Suture+Technique+on+Resistance+to+Gap+Formation+and+Tensile+Strength+of+Repaired+Tendons:+An+Ex+Vivo+Mechanical+Study.">Effects of a Q Suture Technique on Resistance to Gap Formation and Tensile Strength of Repaired Tendons: An Ex Vivo Mechanical Study.</a> Journal of Hand Surgery - American volume. 45 (3), 258 (2020).</li><li>Hirpara, K. M., Sullivan, P. J., O'Sullivan, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effects+of+freezing+on+the+tensile+properties+of+repaired+porcine+flexor+tendon.">The effects of freezing on the tensile properties of repaired porcine flexor tendon.</a> Journal of Hand Surgery - American volume. 33 (3), 353-358 (2008).</li><li>Tang, J. B., Zhang, Y., Cao, Y., Xie, R. 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K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effects+of+core+suture+purchase+on+the+biomechanical+characteristics+of+a+multistrand+locking+flexor+tendon+repair:+a+cadaveric+study.">The effects of core suture purchase on the biomechanical characteristics of a multistrand locking flexor tendon repair: a cadaveric study.</a> Journal of Hand Surgery - American volume. 35 (7), 1165-1171 (2010).</li><li>Vanhees, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+suture+preloading+on+the+force+to+failure+and+gap+formation+after+flexor+tendon+repair.">The effect of suture preloading on the force to failure and gap formation after flexor tendon repair.</a> Journal of Hand Surgery - American volume. 38 (1), 56-61 (2013).</li><li>Smith, G. H., Huntley, J. S., Anakwe, R. E., Wallace, R. J., McEachan, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tensioning+of+Prolene+reduces+creep+under+cyclical+load:+relevance+to+a+simple+pre-operative+manoeuvre.">Tensioning of Prolene reduces creep under cyclical load: relevance to a simple pre-operative manoeuvre.</a> Journal of Hand Surgery - European volume. 37 (9), 823-825 (2012).</li><li>Wu, Y. F., Tang, J. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+tension+across+the+tendon+repair+site+on+tendon+gap+and+ultimate+strength.">Effects of tension across the tendon repair site on tendon gap and ultimate strength.</a> Journal of Hand Surgery - American volume. 37 (5), 906-912 (2012).</li><li>Wu, Y. F., Tang, J. 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The results of the current study showed that Q suture not only reduced the gapping and improves tensile strength of the repaired tendons but was also timesaving and labor-saving. Nonetheless, some key points regarding tendon repair in the current study should be noted.
First, we tried to select tendon samples that were similar in shape and size because we were not sure whether tendon size would have a notable impact on tensile strength after repair. In addition, tendon samples can be preserved...

Gap formation at tendon repair site affects tendon repair strength and gliding resistance substantially. The consequences of gapping between tendon ends may ultimately impede tendon healing in vivo1. It has been reported that the presence of a gap larger than 2 mm at the repair site lead to a significant increase in the gliding resistance of repaired intrasynovial tendon in cadaveric hands2. A study in a canine model has shown that a gap size larger than 3 mm would impair the tendon healing strength and stiffness3. Therefore, improving resistance and decreasing the risk of gapping between tendon ends are critical for tendon repair.
Addition of peripheral sutures has been shown to reduce the gapping at the tendon repair site thereby improving gliding function of the repaired tendons4,5,6. During the last few decades, a number of peripheral sutures have been developed, including the interlocking cross stitch (IXS), interlocking horizontal mattress (IHM), and cross-linked Silfverski&#246;ld and Lembert, et al7,8,9,10. These peripheral sutures have proven to be superior to running peripheral sutures with respect to gapping resistance in tendon repair. However, many of these sutures are complex in structure and difficult to perform, thereby limiting their widespread applications. An ideal suture for tendon repair should aim to prevent gap formation while avoiding the addition of bulk to the repair site after tendon repair. Currently, running peripheral suture remains a popular technique due to its simplicity.
In a recent study, a technique, alternative to peripheral suture, named Q suture, because its shape is similar to the letter &#8220;Q&#8221;, is presented11. Here, we compared this suturing technique with running peripheral suture to check for the differences in gapping resistance and the tensile strength of repaired tendons. The results showed that Q suture was more efficient in enhancing the gapping resistance and ultimate strength of the repaired tendons in the cyclic loading test. Therefore, this article aims to provide a detailed description of how to perform Q suture technique and the biomechanical settings for testing the effects of Q suture on the properties of the repaired tendons.

<table>
	<tbody>
		<tr>
			<td>4-0 suture</td>
			<td>Ethicon, Somerville, NJ</td>
			<td>Ethilon 1667</td>
			<td></td>
		</tr>
		<tr>
			<td>6-0 suture</td>
			<td>Ethicon, Somerville, NJ</td>
			<td>Ethilon 689</td>
			<td></td>
		</tr>
		<tr>
			<td>biomechanical testing machine</td>
			<td>Instron Corp, Norwood, MA</td>
			<td>Instron 3365</td>
			<td></td>
		</tr>
		<tr>
			<td>biomechanical testing software</td>
			<td>Instron Corp, Norwood, MA</td>
			<td>Bluehill 2</td>
			<td></td>
		</tr>
	</tbody>
</table>

using q suture to enhance resistance to gap formation and tensile strength of repaired flexor tendons

Peripheral epitendinous sutures are believed to enhance core suture strength in tendon repair and decrease the risk of gapping between tendon ends. Here Q suture, an alternative to peripheral sutures, is presented for the use in tendon repair. Its effects on gap formation and tensile strength of the repaired tendons were compared with conventional running peripheral sutures. Three 2-strand sutures and three 4-strand sutures were used in repairing porcine tendons. The time required for performing 2Q and running sutures were recorded. The repaired tendons were subjected to a cyclic loading test, and the cycle number, during which a 2-mm gap was formed, was determined. After the cyclic loading, the gap size at the tendon ends and the ultimate strength of the repaired tendons were measured. Augmentation with the Q sutures reduced the number of tendons showing 2-mm gaps at tendon ends during cyclic loading. With addition of Q sutures 2-strand sutures significantly increased the ultimate strength of the repaired tendons and 4-strand sutures decreased the gap distance at the repair site of tendons. The time required for performing 2Q sutures was significantly less than that for running sutures. Therefore, we conclude that the Q suture is efficient in enhancing the tensile resistance and tendon repair strength and can be an alternative to conventional peripheral sutures.

Table 1 shows that addition of Q suture reduced the number of tendons with 2-mm gapping during cyclic loading in both 2-strand and 4-strand repairs. All tendons repaired with 2-strand and 4-strand core sutures formed a 2-mm gap, whereas none of the tendons repaired with 2-strand plus 2Q and only half of those repaired with 4-strand plus 2Q had a 2-mm gapping after 10 cycles. More tendons repaired with 2-strand plus running or 4-strand plus running sutures showed a 2-mm gap than those augmented with Q sut...

Watch this Scientific Journal Video about Using Q Suture to Enhance Resistance to Gap Formation and Tensile Strength of Repaired Flexor Tendons at JoVE.com

Using Q Suture to Enhance Resistance to Gap Formation and Tensile Strength of Repaired Flexor Tendons

Here, we present a &#8220;Q&#8221; suture technique that can be performed in tendon repair and its effects on the gap formation and tensile strength of the repaired tendons. Q suture is shown to be efficient in enhancing the tensile resistance and tendon repair strength.

Peripheral epitendinous sutures are believed to enhance core suture strength in tendon repair and decrease the risk of gapping between tendon ends. Here Q ...

Peripheral sutures can enhance the core suture strength and decrease the risk for gaping between repaired tendon ends. We present Q sutures as an alternative to conventional peripheral sutures. Compared to conventional running peripheral sutures, Q sutures are very easy to perform, are time-saving, and demonstrate a superior performance in resisting gapping in tendon repair.To perform a tendon repair, begin by marking the anterior surface of one of the porcine tendon stumps with two points that are 10 millimeters from the cut tendon, one fourth of the way from the left and right sides of the tendon in the mediolateral direction. Mark each of the left and right lateral surfaces of the tendon with one point that is eight millimeters from each cut tendon end. And locate the point in the middle of the anterior-posterior direction.Then use a vernier caliper to measure all of the lengths between each set of points. Using four zero sutures, insert a needle into the cut surface of one tendon stump from the middle point in the anterior-posterior direction, and one fourth of the way from the left in the medial-lateral direction. Draw a region of interest around the selected neuron and draw a second larger region of interest around the tail that includes the first region of interest.Reinsert the needle obliquely from point three and pass the needle transversely toward point four. Pull out the suture to create a small loop at the lateral surface of the tendon, and reinsert the needle obliquely from point two, passing the needle longitudinally toward the cut end. Then pull out the suture.To form a symmetrical repair, insert the needle into the cut end of the other tendon stump and suture the other stump with the same construct. Tighten the suture with a 10%shortening of the tendon segment within the core suture. And tie the tendon ends together with three to four knots to complete the two-strand core suture.To complete a four-strand core suture, repeat the suturing process as just demonstrated. To add a Q suture, insert the same needle into the tendon anterior surface, two millimeters away from the joined tendon end. And withdraw the needle on the posterior surface of the tendon.Reinsert the needle into the posterior surface of the tendon at two millimeters away from the other side of the joined tendon end. Pull out the suture from the anterior surface of the tendon and the tie three knots to complete the first Q suture. Then repeat the procedure to complete the second Q suture.To add a running suture in the two-strand or four-strand core suture plus running group, use a six zero suture to add a running epitenon suture of nine to 10 stitches to the tendon ends, keeping a similar purchase of 1.5 millimeters and a depth of one millimeter. When all of the sutures have been placed, cover the repaired tendon with wet gauze. Before performing biomechanical testing of the repairs, open the testing software and navigate to the home screen.Click method to create a test method, and click New to open the create a new test method dialogue box. Select the tension test profile method test type and click create. Click save to name and save the test method file and click control and pretest in the navigation bar to open the control pre-test screen in the method tab.Click preload and set the control mode to tensile extension, the rate to 25 millimeters per minute, the channel to load, and the value to 5 Newtons. Enable the autobalance and add the available channels of load to the selected channels. Click test to open the setup control test screen, and click edit profile of this cyclic loading to open the test profile or dialog box.Insert four blocks. In the first block, set the mode to tensile extension, the shape to triangle, the maximum load to eight Newtons in the two-strand repairs and 15 Newtons in the four-strand repairs, the minimum load to zero Newtons, the rate to 25 millimeters per minute, and the cycle to 10. In the second block set the mode to tensile extension, the shape to absolute ramp, the rate to 25 millimeters per minute, and the end point to eight Newtons in the two-strand repairs and 15 Newtons in the four-strand repairs.In the third block, set the mode to tensile extension, the shape to hold, the criteria to duration, and the duration to eight seconds. In the fourth block, set the mode to tensile extension, the shape to absolute ramp, the rate to 25 millimeters per minute, and the end point as 100 Newtons. Then click save and exit.Next, open the control end of test screen and set criteria one to rate of load, and the sensitivity to 40%In the calculation setup screen, add available calculations of absolute peak to the selected calculations. Select load in the drop down list of channel and apply the absolute peak to the four absolute ramp. Open the results'one column screen, select a maximum load, and add load to the selected results.Then click save, and close. To perform a biomechanical test, set the initial distance between the upper and lower clamps of the testing machine to five centimeters. Wrap the tendon with dry gauzes, two to three centimeters away from the cut end, and mount the gauze wrapped then in segments into the upper and lower clamps, keeping the tendon as vertical as possible.When the tendon has been mounted, click test on the home screen and select the save to test method file. Click next and select a location, and enter a name to save the sample data file. The test tab will be displayed.Click open load cell set up dialog, calibrate and okay to remove the load from the load cell. Click open live displays set up dialogue and select tensile extension in the drop-down list of channel one. Select cycle count in the dropdown list of channel three, and select three in the live displays.Click open control panel set up dialog and select balanced load in the dropdown list of key 1, and reset gauge length of key 2. Click balance load, reset gauge length and start to run a test for each specimen in the sample. During the cyclic loading, record the number of tendons with a two millimeter gap between the two ends.During the eight-second pause at the maximum load after the 10th cycle, measure the gap distance between the tendon ends. After measuring the gap, pull the tendon upward until the repair ruptures, and record the ultimate breaking strain. Then click stop, return, and finish to save the results.As illustrated in the table, in this representative analysis, the addition of Q suture reduce the number of tendons with two millimeter gapping during cyclic loading in both two-strand and four-strand repairs. All of the tenants repaired with two and four-strand core sutures formed a two-millimeter gap, whereas none of the tendons repaired with two strand plus two Q, and only half of those repaired with four strand plus two Q had a two-millimeter gapping after 10 cycles. Further, more tendons repaired with two-strand plus running or four-strand plus running sutures showed a two millimeter gap, then those augmented with Q sutures.With two strand repairs, the addition of the Q suture or running sutures both reduce the gap distance between tendon ends after cyclic loading, but only Q suture addition significantly increase the ultimate strength of the repaired tendon. The addition of the Q suture also minimize the gap distance with four-strand repairs, although the ultimate strength of the repaired tendons was not affected. In addition, the average time required for performing two Q sutures was significantly shorter than that for a running suture.The facts of Q sutures when combined with other types of core sutures warrant for the study to confirm the efficacy of Q sutures.

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Research

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Medicine

The Measurement and Treatment of Suppression in Amblyopia

Amblyopia, a developmental disorder of the visual cortex, is one of the leading causes of visual dysfunction in the working age population. Current estimates put the prevalence of amblyopia at approximately 1-3%1-3, the majority of cases being monocular2. Amblyopia is most frequently caused by ocular misalignment (strabismus), blur induced by unequal refractive error (anisometropia), and in some cases by form deprivation.
Although amblyopia is initially caused by abnormal visual input in infancy, once established, the visual deficit often remains when normal visual input has been restored using surgery and/or refractive correction. This is because amblyopia is the result of abnormal visual cortex development rather than a problem with the amblyopic eye itself4,5 . Amblyopia is characterized by both monocular and binocular deficits6,7 which include impaired visual acuity and poor or absent stereopsis respectively. The visual dysfunction in amblyopia is often associated with a strong suppression of the inputs from the amblyopic eye under binocular viewing conditions8. Recent work has indicated that suppression may play a central role in both the monocular and binocular deficits associated with amblyopia9,10 .
Current clinical tests for suppression tend to verify the presence or absence of suppression rather than giving a quantitative measurement of the degree of suppression. Here we describe a technique for measuring amblyopic suppression with a compact, portable device11,12 . The device consists of a laptop computer connected to a pair of virtual reality goggles. The novelty of the technique lies in the way we present visual stimuli to measure suppression. Stimuli are shown to the amblyopic eye at high contrast while the contrast of the stimuli shown to the non-amblyopic eye are varied. Patients perform a simple signal/noise task that allows for a precise measurement of the strength of excitatory binocular interactions. The contrast offset at which neither eye has a performance advantage is a measure of the "balance point" and is a direct measure of suppression. This technique has been validated psychophysically both in control13,14 and patient6,9,11 populations.
In addition to measuring suppression this technique also forms the basis of a novel form of treatment to decrease suppression over time and improve binocular and often monocular function in adult patients with amblyopia12,15,16 . This new treatment approach can be deployed either on the goggle system described above or on a specially modified iPod touch device15.

Amblyopia is a developmental disorder of the visual cortex that is often accompanied by strong suppression of one eye. We present a new technique for measuring and treating interocular suppression in patients with amblyopia that can be deployed using virtual reality goggles or a portable iPod Touch device.

Amblyopia, a developmental disorder of the visual cortex, is one of the leading causes of visual dysfunction in the working age population. Current ...

Adapted Resistance Training Improves Strength in Eight Weeks in Individuals with Multiple Sclerosis

Hip weakness is a common symptom affecting walking ability in people with multiple sclerosis (MS). It is known that resistance strength training (RST) can improve strength in individuals with MS, however; it remains unclear the duration of RST that is needed to make strength gains and how to adapt hip strengthening exercises for individuals of varying strength using only resistance bands. This paper describes the methodology to set up and implement an adapted resistance strength training program, using resistance bands, for individuals with MS. Directions for pre- and post-strength tests to evaluate efficacy of the strength-training program are included. Safety features and detailed instructions outline the weekly program content and progression. Current evidence is presented showing that significant strength gains can be made within 8 weeks of starting a RST program. Evidence is also presented showing that resistance strength training can be successfully adapted for individuals with MS of varying strength with little equipment.

Hip weakness is a common symptom affecting walking ability in people with multiple sclerosis. Isolated muscle strengthening is a useful method to target specific weaknesses. This protocol describes a progressive resistance-training program using exercise bands to increase hip muscle strength.

Hip weakness is a common symptom affecting walking ability in people with multiple sclerosis (MS). It is known that resistance strength training (RST) can ...

Murine Flexor Tendon Injury and Repair Surgery

Tendon connects skeletal muscle and bone, facilitating movement of nearly the entire body. In the hand, flexor tendons (FTs) enable flexion of the fingers and general hand function. Injuries to the FTs are common, and satisfactory healing is often impaired due to excess scar tissue and adhesions between the tendon and surrounding tissue. However, little is known about the molecular and cellular components of FT repair. To that end, a murine model of FT repair that recapitulates many aspects of healing in humans, including impaired range of motion and decreased mechanical properties, has been developed and previously described. Here an in-depth demonstration of this surgical procedure is provided, involving transection and subsequent repair of the flexor digitorum longus (FDL) tendon in the murine hind paw.&#160;This technique can be used to conduct lineage analysis of different cell types, assess the effects of gene gain or loss-of-function, and to test the efficacy of pharmacological interventions in the healing process. However, there are two primary limitations to this model: i) the FDL tendon in the mid-portion of the murine hind paw, where the transection and repair occur, is not surrounded by a synovial sheath. Therefore this model does not account for the potential contribution of the sheath to the scar formation process. ii) To protect the integrity of the repair site, the FT is released at the myotendinous junction, decreasing the mechanical forces of the tendon, likely contributing to increased scar formation. Isolation of sufficient cells from the granulation tissue of the FT during the healing process for flow cytometric analysis has proved challenging; cytology centrifugation to concentrate these cells is an alternate method used, and allows for generation of cell preparations on which immunofluorescent labeling can be performed. With this method, quantification of cells or proteins of interest during FT healing becomes possible.

Flexor tendons in the hand are commonly injured, leading to impaired hand function. However, the scar-tissue healing response is not well characterized. A murine model of flexor tendon healing is demonstrated here. This model can enhance overall understanding of the healing process and assess therapeutic approaches to improve healing.

Tendon connects skeletal muscle and bone, facilitating movement of nearly the entire body. In the hand, flexor tendons (FTs) enable flexion of the fingers ...

Transplantation of Schwann Cells Inside PVDF-TrFE Conduits to Bridge Transected Rat Spinal Cord Stumps to Promote Axon Regeneration Across the Gap

Among various models for spinal cord injury in rats, the contusion model is the most often used because it is the most common type of human spinal cord injury. The complete transection model, although not as clinically relevant as the contusion model, is the most rigorous method to evaluate axon regeneration. In the contusion model, it is difficult to distinguish regenerated from sprouted or spared axons due to the presence of remaining tissue post injury. In the complete transection model, a bridging method is necessary to fill the gap and create continuity from the rostral to the caudal stumps in order to evaluate the effectiveness of the treatments. A reliable bridging surgery is essential to test outcome measures by reducing the variability due to the surgical method. The protocols described here are used to prepare Schwann cells (SCs) and conduits prior to transplantation, complete transection of the spinal cord at thoracic level 8 (T8), insert the conduit, and transplant SCs into the conduit. This approach also uses in situ gelling of an injectable basement membrane matrix with SC transplantation that allows improved axon growth across the rostral and caudal interfaces with the host tissue.

This article describes a technique to insert a hollow conduit between the spinal cord stumps after complete transection and fill with Schwann cells (SCs) and injectable basement membrane matrix in order to bridge and promote axon regeneration across the gap.

Among various models for spinal cord injury in rats, the contusion model is the most often used because it is the most common type of human spinal cord ...

Micro-dissection of Enamel Organ from Mandibular Incisor of Rats Exposed to Environmental Toxicants

Enamel defects resulting from environmental conditions and ways of life are public health concerns because of their high prevalence. These defects result from altered activity of cells responsible for enamel synthesis named ameloblasts, which present in enamel organ. During amelogenesis, ameloblasts follow a specific and precise sequence of events of proliferation, differentiation, and death. A rat continually growing incisors is a suitable experimental model to study ameloblast activity and differentiation stages in physiological and pathological conditions. Here, we describe a reliable and consistent method to micro-dissect enamel organ of rats exposed to environmental toxicants. The micro-dissected dental epithelia contain secretion- and maturation-stage ameloblasts that may be used for qualitative experiments, such as immunohistochemistry assays and in situ hybridization, as well as for quantitative analyses such as RT-qPCR, RNA-seq, and Western blotting.

Understanding enamel formation and possible alterations requires the study of ameloblast activity. Here, we describe a reliable and consistent method to micro-dissect enamel organs containing secretion- and maturation-stage ameloblasts that may be used for further quantitative and qualitative experimental procedures.

Enamel defects resulting from environmental conditions and ways of life are public health concerns because of their high prevalence. These defects result ...

A Clinical Trial Assessing the Safety, Efficacy, and Delivery of Olive-Oil-Based Three-Chamber Bags for Parenteral Nutrition

Limited evidence exists to precisely estimate efficacy and safety differences between parenteral nutrition (PN) prepared using olive-oil-based three-chamber bags (3CBs) and soybean-oil-based compounded bags (CoBs) in hospitalized adult patients. We designed a multicenter, randomized, prospective, open-label, noninferiority protocol to compare the efficacy, safety, and distribution of olive-oil-based 3CBs and soybean-oil-based CoB formulations in adult Chinese patients requiring PN during surgical intervention. Subjects were randomized to receive either one of the study treatments using an interactive voice or web-based recognition system in accordance with the randomization code. Randomization was further stratified based on the study site and surgical category. Both treatment groups received similar amounts of calories and protein. In addition, the two study treatments contained a similar composition of the amino-acid component. The only difference between the two PN formulations was the lipid constitution. The duration of administration of study treatments was a minimum of 5 days up to a maximum of 14 days after the surgical procedure. The primary efficacy endpoint was serum prealbumin levels on day 5 of the study. Noninferiority was proved if the anti-log of the lower bound of the 95% confidence interval (CI) of the treatment difference was at least 0.80. Other efficacy measures included treatment preparation time; duration to achieve tolerability of oral nutrition; associated infectious complications; length of hospitalization; and laboratory assessment of markers of nutrition, inflammation, metabolism, and oxidative stress. A total of 458 patients were enrolled in the study. The results showed that olive-oil-based 3CBs were non-inferior to soybean-based CoBs, besides being well tolerated. The infection rate was found to be significantly lower in the olive-oil-based 3CB group. Thus, this study may be used as a reference for future research on lipid emulsion and 3CBs.

Here, we present a protocol for a study comparing the efficacy, safety, and delivery of olive-oil-based 3CB and soybean-oil-based CoB formulations in adults requiring parenteral nutrition. The results revealed that olive-oil-based 3CBs is non-inferior and well tolerated compared to soybean formulations.

Limited evidence exists to precisely estimate efficacy and safety differences between parenteral nutrition (PN) prepared using olive-oil-based ...

Improved Renal Denervation Mitigated Hypertension Induced by Angiotensin II Infusion

The benefits of renal sympathetic denervation (RDN) on blood pressure have been proved in a large number of clinical trials in recent years. However, the regulatory mechanism of RDN on hypertension remains elusive. Thus, it&#39;s essential to establish a simpler RDN model in mice. In this study, osmotic mini pumps filled with Angiotensin II were implanted in 14-week-old C57BL/6 mice. One week after the implantation of the mini-osmotic pump, a modified RDN procedure was performed on bilateral renal arteries of the mice using phenol. Age-sex-matched mice were given saline and served as sham group. Blood pressure was measured at baseline and every week subsequently for 21 days. Then, renal artery, abdominal aorta and heart were collected for histological examination using H&#38;E and Masson staining. In this study, we present a simple, practical, repeatable, and standardized RDN model, which can control hypertension and alleviate cardiac hypertrophy. The technique can denervate peripheral renal sympathetic nerves without renal artery damage. Compared to previous models, the modified RDN facilitates the study of the pathobiology and pathophysiology of hypertension.

Here, we present a protocol for renal sympathetic denervation (RDN) in mice with hypertension induced by Angiotensin II infusion. The procedure is repeatable, convenient and allows to study the regulatory mechanisms of RDN on hypertension and cardiac hypertrophy.

The benefits of renal sympathetic denervation (RDN) on blood pressure have been proved in a large number of clinical trials in recent years. However, the ...

Network Pharmacology Prediction and Experimental Validation of Trichosanthes-Fritillaria thunbergii Action Mechanism Against Lung Adenocarcinoma

We aimed to study the mechanism of Trichosanthes-Fritillaria thunbergii in treating lung adenocarcinoma (LUAD) based on network pharmacology and experimental verification. The effective components and potential targets of Trichosanthis and Fritillaria thunbergii were collected by high-throughput experiment and reference-guided (HERB) database of traditional Chinese medicine and a similarity ensemble approach (SEA) database, and the LUAD-related targets were queried by the GeneCards and Online Mendelian Inheritance in Man (OMIM) databases. A drug-component-disease-target network was constructed by Cytoscape software. Protein-protein interaction (PPI) network, gene ontology (GO) function, and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analyses were conducted to obtain core targets and key pathways. An aqueous extract of Trichosanthes-Fritillaria thunbergii and A549 cells were used for the subsequent experimental validation. Through the HERB database and literature search, 31 effective compounds and 157 potential target genes of Trichosanthes-Fritillaria thunbergii were screened, of which 144 were regulatory targets of Trichosanthes-Fritillaria thunbergii in the treatment of lung adenocarcinoma. The GO functional enrichment analysis showed that the mechanism of action of Trichosanthes-Fritillaria thunbergii against lung adenocarcinoma is mainly protein phosphorylation. The KEGG pathway enrichment analysis suggested that the treatment of lung adenocarcinoma by Trichosanthes-Fritillaria thunbergii mainly involves the PI3K/AKT signaling pathway. The experimental validation showed that an aqueous extract of Trichosanthes-Fritillaria thunbergii could inhibit the proliferation of A549 cells and the phosphorylation of AKT. Through network pharmacology and experimental validation, it was verified that the PI3K/AKT signaling pathway plays a vital role in the action of Trichosanthes-Fritillaria thunbergii in treating lung adenocarcinoma.

Network Pharmacology Prediction and Experimental Validation of Trichosanthes-Fritillaria thunbergii Action Mechanism Against Lung Adenocarcinoma

This study reveals the mechanism of Trichosanthes-Fritillaria thunbergii in treating lung adenocarcinoma based on network pharmacology and experimental verification. The study also demonstrates that the PI3K/AKT signaling pathway plays a vital role in the action of Trichosanthes-Fritillaria thunbergii in treating lung adenocarcinoma.

We aimed to study the mechanism of Trichosanthes-Fritillaria thunbergii in treating lung adenocarcinoma (LUAD) based on network pharmacology and ...

Standardized Tuina Manipulation for Knee Osteoarthritis in Rats

Tuina Manipulation to Reduce Inflammation and Cartilage Loss in Knee Osteoarthritis Rats

Clinical trials suggest that Tuina manipulation is effective in treating knee osteoarthritis (KOA), while further studies are required to discover its mechanism. Therefore, the manipulation of animal models of knee osteoarthritis is critical. This protocol provides a standard process for Tuina manipulation on KOA rats and a preliminary exploration of the mechanism of Tuina for KOA. The press and kneading manipulation method (a kind of Tuina manipulation that refers to pressing and kneading the specific area of the body surface) is applied on 5 acupoints around the knee joint of rats. The force and frequency of the manipulation were standardized by finger pressure recordings, and the position of the rat during manipulation is described in detail in the protocol. The effect of manipulation can be measured by pain behavior tests and microscopic findings in synovial and cartilage. KOA rats showed significant improvement in pain behavior. The synovial tissue inflammatory infiltration was reduced in the Tuina group, and the expression of tumor necrosis factor (TNF)-&#945; was significantly lower. Compared to the control group, chondrocyte apoptosis was less in the Tuina group. This study provides a standardized protocol for Tuina manipulation on KOA rats and preliminary proof that the therapeutic effects of Tuina may be related to reducing synovial inflammation and delayed chondrocyte apoptosis.

Author Spotlight: Understanding the Mechanism of Tuina Manipulation in Rats 

We present a protocol for Tuina manipulation performed on plaster-immobilized-induced knee osteoarthritis rats. Based on the preliminary results, it suggested that the efficacy of the method relied on the reduction of inflammation and cartilage loss.

Clinical trials suggest that Tuina manipulation is effective in treating knee osteoarthritis (KOA), while further studies are required to discover its ...

Standardized Tuina Protocol for Rat DRG Compression Model

Analgesic Effect of Tuina on Rat Models with Compression of the Dorsal Root Ganglion Pain

Neuropathic pain is a prevalent condition that affects 6.9%-10% of the population and results from nerve damage due to various etiologies, such as lumbar disc herniation, spinal canal stenosis, and intervertebral foramen stenosis. Although Tuina, a traditional Chinese manual therapy, has shown analgesic effects in clinical practice for the treatment of neuropathic pain, its underlying neurobiological mechanisms remain unclear. Animal models are essential for elucidating the basic principles of Tuina. In this study, we propose a standardized Tuina protocol for rats with compression of the dorsal root ganglion (DRG), which involves inducing DRG compression by inserting a stainless steel rod into the intervertebral foramen, performing Tuina manipulation with specific parameters of location, intensity, and frequency in a controlled environment, and assessing the behavioral and histopathological outcomes of Tuina treatment. This article also discusses the potential clinical implications and limitations of the study and suggests directions for future research on Tuina.

Author Spotlight: Analgesic Effect of Tuina on Rat Models with Compression of the Dorsal Root Ganglion Pain  

This article presents a manipulation for treating chronic compression of the dorsal root ganglion in rats using Tuina therapy, along with a method for evaluating its effectiveness based on pain behavior and histopathological results.

Neuropathic pain is a prevalent condition that affects 6.9%-10% of the population and results from nerve damage due to various etiologies, such as lumbar ...