Autologous Elastic Cartilage for Laryngoplasty: Histologic Evaluation in a Rabbit Model

A wide range of materials have been used to achieve medialization of the paralyzed vocal fold. Recently, medialization techniques using autologous cartilage have been described, but little information is available on cartilage integration and viability in this situation. In this prospective, experimental, controlled study, right vocal fold paralysis was surgically induced in 30 New Zealand rabbits. An autologous auricular cartilage transplant was inserted in the vocal fold in 15 animals. In the control group, only the laryngeal nerve was sectioned. Each group was divided into two groups with follow-ups of 6 weeks and 6 months, respectively. Histologic studies revealed no inflammatory reaction against the cartilage transplants. There were no differences in the transplant surfaces in the 6-week and 6-month groups. The results show tissue integration and a low level of initial transplant resorption that stabilizes with time. Autologous auricular cartilage appears to be an appropriate material for type I thyroplasty procedures because of the low absorption rate.

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Effect of Acute Increases in Intraocular Pressure on Corneal Pachymetry in Rabbit Eyes Treated with Timolol Maleate

The Open Ophthalmology Journal ◽

10.2174/1874364101812010314 ◽

2018 ◽

Vol 12 (1) ◽

pp. 314-321

Author(s):

Cristina Sánchez-Barahona ◽

Gema Bolívar ◽

Dimitrios G. Mikropoulos ◽

Anastasios G. Konstas ◽

Miguel A. Teus

Keyword(s):

Intraocular Pressure ◽

Anterior Chamber ◽

Central Corneal Thickness ◽

Corneal Thickness ◽

Rabbit Model ◽

Controlled Study ◽

Control Group ◽

Study Group ◽

Timolol Maleate

Objective: To evaluate in an in vivo rabbit model, the effect of topical timolol maleate therapy on the central corneal thickness response to acute intraocular pressure increases. Method: In this prospective and interventional controlled study, the central corneal thickness and intraocular pressure were measured in vivo in 12 rabbit eyes treated with topical timolol maleate for 1 month and in 12 controls at baseline, and after the intraocular pressure (measured by direct cannulation of the anterior chamber) was increased to 15 and 30 mmHg using a forced saline infusion into the anterior chamber. Results: There were no significant differences in the basal central corneal thickness values (control group, 373.2±12.9 µm; study group, 377.5±19.2 µm, p=0.5) or the central corneal thickness values when the intraocular pressure was increased to 15 mmHg (control group, 335.2±14.3 µm; study group, 330.0±32.1 µm, p=0.6) and to 30 mmHg (study group, 318.8±25.3 µm; control group, 329.8±21.0 µm, p=0.3). Conclusion: Rabbit corneas treated with topical timolol maleate for 1 month did not show a strain response to acute intraocular pressure increases that differed from control eyes. This is in contrast to a previous finding in which rabbit eyes treated with prostaglandin analogues had a greater decrease in central corneal thickness in response to a sudden intraocular pressure increase compared with untreated corneas.

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Does handwriting the name of a potential trial participant on an invitation letter improve recruitment rates? A randomised controlled study within a trial

F1000Research ◽

10.12688/f1000research.18939.1 ◽

2019 ◽

Vol 8 ◽

pp. 659 ◽

Cited By ~ 1

Author(s):

Jennifer McCaffery ◽

Alex Mitchell ◽

Caroline Fairhurst ◽

Sarah Cockayne ◽

Sara Rodgers ◽

...

Keyword(s):

Intervention Group ◽

Small Sample ◽

Controlled Study ◽

Control Group ◽

Trial Participant ◽

Invitation Letter ◽

Wide Range ◽

Study Within A Trial ◽

Secondary Outcomes ◽

Randomised Controlled

Background: Randomised controlled trials (RCTs) often fail to recruit to target, resulting in a lack of generalisability of findings. A wide range of strategies for potentially increasing recruitment have been identified; however, their effectiveness has not been established. The aim of this study within a trial (SWAT) was to evaluate the effectiveness of handwritten personalisation of an invitation letter as part of a trial recruitment pack on recruitment to a host RCT. Methods: A pragmatic, two-armed RCT was conducted, embedded within an existing falls prevention trial (OTIS) in men and women aged 65 years and over living in the community. Participants were randomised 1:1 to receive an OTIS recruitment pack containing an invitation letter on which their name was handwritten (intervention group), or one on which it was printed (control group). The primary outcome was randomisation into the host trial. Secondary outcomes related to trial eligibility and retention. Analyses were via logistic regression and Cox Proportional Hazards regression. Results: Of the 317 SWAT participants, 12 (3.8%) were randomised into the OTIS trial: 3 (handwritten: 3/159 [1.9%]; printed: 9/158 [5.7%]; difference -3.8%, 95% CI -8.0% to 0.4%). There was weak evidence, against the intervention, of a difference in the likelihood of participants being randomised into the host trial between the two groups (OR 0.32, 95% CI 0.08 to 1.20, p=0.09). There were no statistically significant differences between the intervention and control groups on any of the secondary outcomes. Conclusions: There was no evidence that personalisation of invitation letters improved recruitment to the OTIS trial. However, due to the small sample size, the results should be interpreted with caution. These findings need to be replicated across larger studies and wider populations. Registration: ISRCTN22202133.

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Anti-fibrotic effects of the antihistamine ketotifen in a rabbit model of arthrofibrosis

Bone and Joint Research ◽

10.1302/2046-3758.96.bjr-2019-0272.r2 ◽

2020 ◽

Vol 9 (6) ◽

pp. 302-310

Author(s):

Meagan E Tibbo ◽

Afton K Limberg ◽

Christopher G Salib ◽

Travis W Turner ◽

Alex R McLaury ◽

...

Keyword(s):

Gene Expression ◽

Messenger Rna ◽

Smooth Muscle Actin ◽

Fibrous Tissue ◽

Rabbit Model ◽

Control Group ◽

Gene Expression Analyses ◽

Molecular Effects ◽

Contracture Formation ◽

Surgically Induced

Aims Arthrofibrosis is a relatively common complication after joint injuries and surgery, particularly in the knee. The present study used a previously described and validated rabbit model to assess the biomechanical, histopathological, and molecular effects of the mast cell stabilizer ketotifen on surgically induced knee joint contractures in female rabbits. Methods A group of 12 skeletally mature rabbits were randomly divided into two groups. One group received subcutaneous (SQ) saline, and a second group received SQ ketotifen injections. Biomechanical data were collected at eight, ten, 16, and 24 weeks. At the time of necropsy, posterior capsule tissue was collected for histopathological and gene expression analyses (messenger RNA (mRNA) and protein). Results At the 24-week timepoint, there was a statistically significant increase in passive extension among rabbits treated with ketotifen compared to those treated with saline (p = 0.03). However, no difference in capsular stiffness was detected. Histopathological data failed to demonstrate a decrease in the density of fibrous tissue or a decrease in α-smooth muscle actin (α-SMA) staining with ketotifen treatment. In contrast, tryptase and α-SMA protein expression in the ketotifen group were decreased when compared to saline controls (p = 0.007 and p = 0.01, respectively). Furthermore, there was a significant decrease in α-SMA (ACTA2) gene expression in the ketotifen group compared to the control group (p < 0.001). Conclusion Collectively, these data suggest that ketotifen mitigates the severity of contracture formation in a rabbit model of arthrofibrosis. Cite this article: Bone Joint Res 2020;9(6):302–310.

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A New Approach Using Manganese-Enhanced MRI to Diagnose Acute Mesenteric Ischemia in a Rabbit Model: Initial Experience

BioMed Research International ◽

10.1155/2015/579639 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Da-wei Zhao ◽

Cheng Cheng ◽

Lian-qin Kuang ◽

Yu-long Zhang ◽

Hai-yun Cheng ◽

...

Keyword(s):

Mesenteric Ischemia ◽

Rabbit Model ◽

Diagnostic Technique ◽

Acute Mesenteric Ischemia ◽

Intestinal Wall ◽

Control Group ◽

Enhanced Mri ◽

Wide Range ◽

Small Intestinal ◽

Manganese Enhanced Mri

Purpose. Manganese-enhanced MRI (MEMRI) has been applied to a wide range of biological and disease research. The purpose of the study was to use MEMRI to diagnose the acute mesenteric ischemia (AMI).Methods. The institutional experimental animal ethics committee approved this study. To optimize the dose of Mn2+infusion, a dose-dependent curve was obtained using Mn2+-enhancedT1map MRI by an intravenous infusion 2.5–20 nmol/g body weight (BW) of 50 nmol/L MnCl2. The eighteen animals were divided into control, sham-operated, and AMI groups. AMI models were performed by ligating the superior mesenteric artery (SMA).T1values were measured onT1maps in regions of the small intestinal wall and relaxation rate (ΔR1) was calculated.Results. A nonlinear relationship between infused MnCl2solution dose and increase in small intestinal wall ΔR1was observed. Control animal exhibited significant Mn2+clearance over time at the dose of 15 nmol/g BW. In the AMI model, ΔR1values (0.95 ± 0.13) in the small intestinal wall were significantly lower than in control group (2.05 ± 0.19) after Mn2+infusion (P< 0.01).Conclusion. The data suggest that MEMRI shows potential as a diagnostic technique that is directly sensitive to the poor or absent perfusion in AMI.

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Psychological characteristics and motivation of women seeking labiaplasty

Psychological Medicine ◽

10.1017/s0033291713001025 ◽

2013 ◽

Vol 44 (3) ◽

pp. 555-566 ◽

Cited By ~ 53

Author(s):

D. Veale ◽

E. Eshkevari ◽

N. Ellison ◽

A. Costa ◽

D. Robinson ◽

...

Keyword(s):

Body Dysmorphic Disorder ◽

Surgical Intervention ◽

Psychological Intervention ◽

Psychological Characteristics ◽

Controlled Study ◽

Control Group ◽

Cosmetic Procedure ◽

Wide Range ◽

Appearance Satisfaction

BackgroundLabiaplasty is an increasingly popular surgical intervention but little is known about the characteristics and motivation of women who seek the procedure or the psychosexual outcome.MethodA total of 55 women seeking labiaplasty were compared with 70 women who did not desire labiaplasty. Various general measures of psychopathology as well as specific measures (Genital Appearance Satisfaction; Cosmetic Procedure Screening for labiaplasty) were used. Labia measurements of the women seeking labiaplasty were also obtained.ResultsWomen seeking labiaplasty did not differ from controls on measures of depression or anxiety. They did, however, express increased dissatisfaction towards the appearance of their genitalia, with lower overall sexual satisfaction and a poorer quality of life in terms of body image. Women seeking labiaplasty reported a significantly greater frequency of avoidance behaviours on all the domains assessed, and greater frequency of safety-seeking behaviours for most of the domains. Key motivations reported for labiaplasty were categorized as cosmetic, functional or sexual. Of the 55 women seeking labiaplasty, 10 met diagnostic criteria for body dysmorphic disorder.ConclusionsThis is the first controlled study to describe some of the characteristics and motivations of women seeking labiaplasty. We identified a wide range of avoidance and safety-seeking behaviours, which occurred more frequently in the labiaplasty group than the control group. These could be used clinically as part of a psychological intervention for women seeking labiaplasty.

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Particulate Silicone for Vocal Fold Medialization: Histologic Evaluation in a Rabbit Model

Otolaryngology ◽

10.1016/j.otohns.2004.06.392 ◽

2004 ◽

Vol 131 (2) ◽

pp. P207-P207

Author(s):

Miguel Caballer ◽

Carlos Calvo ◽

Juan Domenech ◽

Manuel S Berna Sprekelsen

Keyword(s):

Vocal Fold ◽

Rabbit Model ◽

Histologic Evaluation

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Rapid Ischemic Preconditioning with a Short Reperfusion Time Prevents Delayed Paraplegia in a Rabbit Model

The Heart Surgery Forum ◽

10.1532/hsf98.20111039 ◽

2011 ◽

Vol 14 (5) ◽

pp. 317

Author(s):

Mehmet Ozkokeli ◽

Mehmet Ugur Es ◽

Ugur Filizcan ◽

Murat Ugurlucan ◽

Ahmet Sasmazel ◽

...

Keyword(s):

Spinal Cord ◽

Ischemic Preconditioning ◽

Spinal Cord Ischemia ◽

Rabbit Model ◽

Aortic Aneurysms ◽

Aortic Occlusion ◽

Control Group ◽

Protective Mechanisms ◽

Group 13 ◽

Histologic Evaluation

Background: Surgery for thoracic and thoracoabdominal aortic aneurysms can be complicated by a significant incidence of neurogenic deficits due to spinal cord ischemia. In this study, we investigated whether ischemic preconditioning (IPC) improves neurologic outcome in a rabbit model.Methods: Forty rabbits underwent infrarenal aortic occlusion. The IPC group (n = 20) had 10 minutes of aortic occlusion to induce spinal cord ischemia, 40 minutes of reperfusion, and 30 minutes of ischemia, whereas the control group (n = 20) had only 30 minutes of ischemia. Tarlov scoring (0, paraplegia; 4, normal) was used to evaluate neurologic functions 7 days later, and spinal cord segments (L4-L6) were stained with hematoxylin and eosin for histologic evaluation.Results: Complete paraplegia (grade 0) occurred in 15 (75%) of the 20 control animals, whereas in the IPC group, 13 (65%) of 20 animals were completely normal (grade 4) (P < .05).Conclusion: IPC is beneficial for protecting against neurologic damage after transient aortic occlusion in a rabbit model; however, the protective mechanisms are not clear.

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In vivo Evaluation of Fibrous Collagen Dura Substitutes

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.628129 ◽

2021 ◽

Vol 9 ◽

Author(s):

Wenbo Liu ◽

Xin Wang ◽

Jinlei Su ◽

Qingsong Jiang ◽

Jing Wang ◽

...

Keyword(s):

Type I Collagen ◽

Rabbit Model ◽

Surrounding Tissue ◽

Control Group ◽

Regeneration Ability ◽

Type I ◽

Blank Control Group ◽

In Vivo Evaluation ◽

And Performance

Dura substitutes are applied in duraplasty to repair lost or damaged dura. Collagen-based dura substitutes are mainstream products in both the US and Chinese markets. In this study, dura substitute devices with potential dura regeneration ability are evaluated. The dura substitutes are composed of fibrous type I collagen that were purified from bovine tendon. Physical and chemical characterization demonstrated that the tested dura substitute has desirable porous scaffolding structures and is composed of highly purified type I collagen. The collagen dura substitutes were further investigated in vivo with a rabbit model for 6 months to evaluate their safety and performance to repair and regenerate dura. No inflammation or infection was observed during the course of in vivo study. The integration of the collagen dura substitutes with surrounding tissue was normal as compared to native tissue. The macroscopic and microscopic histological assessments of the sampled animal tissue showed that the damaged dura were regenerated. The collagen dura substitutes were resorbed between 3 and 6 months along with newly regenerated dura. Both tissue adhesion and dura repair was the worst in blank control group as compared to those in the collagen dura substitutes. Taken together, regenerative collagen dura substitutes demonstrated with suitable physicochemical properties. The in vivo evaluation in a rabbit model further demonstrated the safety and performance of such substitutes for dura repair and regeneration.

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Characterization of Vocal Fold Vibration in Sulcus Vocalis Using High-Speed Digital Imaging

Journal of Speech Language and Hearing Research ◽

10.1044/2016_jslhr-s-14-0285 ◽

2017 ◽

Vol 60 (1) ◽

pp. 24-37 ◽

Cited By ~ 5

Author(s):

Akihito Yamauchi ◽

Hisayuki Yokonishi ◽

Hiroshi Imagawa ◽

Ken-Ichi Sakakibara ◽

Takaharu Nito ◽

...

Keyword(s):

Digital Imaging ◽

Healthy Subjects ◽

Vocal Fold ◽

High Speed ◽

Control Group ◽

Type I ◽

Strong Correlations ◽

Vocal Fold Vibration ◽

Sulcus Vocalis

Purpose The aim of the present study was to qualitatively and quantitatively characterize vocal fold vibrations in sulcus vocalis by high-speed digital imaging (HSDI) and to clarify the correlations between HSDI-derived parameters and traditional vocal parameters. Method HSDI was performed in 20 vocally healthy subjects (8 men and 12 women) and 41 patients with sulcus vocalis (33 men and 8 women). Then HSDI data were evaluated by assessing the visual–perceptual rating, digital kymography, and glottal area waveform. Results Patients with sulcus vocalis frequently had spindle-shaped glottal gaps and a decreased mucosal wave. Compared with the control group, the sulcus vocalis group showed higher open quotient as well as a shorter duration of the visible mucosal wave, a smaller speed index, and a smaller glottal area difference index ([maximal glottal area – minimal glottal area]/maximal glottal area). These parameters deteriorated in order of the control group and Type I, II, and III sulcus vocalis. There were no gender-related differences. Strong correlations were noted between the open quotient and the type of sulcus vocalis. Conclusions HSDI was an effective method for documenting the characteristics of vocal fold vibrations in patients with sulcus vocalis and estimating the severity of dysphonia.

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Pathologic Effects of External-Beam Irradiation on Human Vocal Folds

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348941112001109 ◽

2011 ◽

Vol 120 (11) ◽

pp. 748-754 ◽

Cited By ~ 7

Author(s):

Eric E. Berg ◽

Vasantha Kolachala ◽

Ryan C. Branski ◽

Susan Muller ◽

Michael M. Johns

Keyword(s):

Muscle Fiber ◽

Vocal Fold ◽

Type I Collagen ◽

Smooth Muscle Actin ◽

Vocal Folds ◽

Collagen Content ◽

Controlled Study ◽

Collagen Type Iv ◽

Type I ◽

External Beam Irradiation

Objectives: We sought to better characterize pathologic changes that occur in the human vocal fold after radiotherapy for head and neck cancer. Methods: In a blinded, controlled study of archived tissue, we evaluated postirradiation salvage laryngectomy vocal fold tissue without evidence of malignant disease. Clinical and demographic patient data were collected. In a blinded fashion, irradiated tissue was compared to nonirradiated, benign control tissue. Histomorphometric analysis was used to assess muscle and collagen organization, superficial lamina propria (SLP) and vocal ligament thickness, vocalis muscle fiber area, collagen content, and hyaluronic acid content. Immunohistochemical analysis was used to assess the content of type I collagen, type IV collagen, vimentin, fibronectin, α–smooth muscle actin, matrix metalloproteinase 9, and laminin. Results: Twenty irradiated vocal folds were evaluated and compared to control specimens. Collagen and muscle disorganization was noted in the irradiated specimens. The SLP and vocal ligament thicknesses and the mean muscle fiber diameters did not differ significantly. The SLP fibronectin and the vocalis muscle and SLP collagen content were significantly increased in the irradiated vocal folds, and the SLP collagen content increased significantly with time between irradiation and resection. The laminin content of irradiated vocalis muscles was significantly decreased. Conclusions: Radiotherapy results in significant vocal fold tissue changes. Having more precisely defined these changes, we plan continued investigation seeking targeted preventive and therapeutic interventions for improved vocal quality following radiotherapy.

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