Chromic Gut Sutures Research Articles

Factors Associated With Complications and Failure in Transoral, Mandible Fracture Repair.

Open reduction internal fixation (ORIF) of the mandible has been a well-studied topic. However, there has not been a study investigating the relationship between suture type and complications. A retrospective chart review of patients who sustained mandibular fractures was conducted at an urban level I trauma center (2010-2018). Descriptive statistics were used to categorize the sociodemographic data. χ2 and Mann-Whitney U testing were used to compare variables between the polyglactin 910 (vicryl) and chromic sutured groups. The study cohort consisted of 102 patients who underwent ORIF of the mandible through the transoral approach. Fifty-nine (57.8%) patients were closed with vicryl suture, whereas 43 (42.2%) with chromic gut suture. There were no differences in sociodemographics, immune status, substance abuse status, fracture type, time to repair, and managing care team between the two groups. Both groups had similar rates of wound dehiscence, infection, and revision surgery. Patients who were operated on earlier were more likely to experience a postoperative infection and dehiscence compared with patients operated on later (P = 0.029 and P = 0.008, respectively). Smokers were more likely to experience dehiscence compared with nonsmokers (P = 0.001). Females and immunocompromised patients were more likely to require revision surgery (P < 0.001). Suture type for transoral, ORIF of the mandible does not impact the rate of infection, wound dehiscence, and revision surgery. However, risk factors for complications can include early operative repair, smoking, female sex, and immunosuppression.

Suture material choice can increase risk of hypersensitivity in hand trauma patients

IntroductionHypersensitivity is an unfortunate potential outcome in patients undergoing surgery following traumatic injuries to their hands. In our practice, we noted that certain suture types may increase the risk of the patient developing hypersensitivity.MethodologyWe conducted a retrospective observational study to investigate if certain suture materials increase the risk of hypersensitivity when used to repair surgical wounds in hand trauma. Patients undergoing hand trauma surgery over a period of five consecutive months were included in the study. Ethics committee approval was obtained from Peninsula Health’s research office.Results184 patients were included in the study. Hypersensitivity was observed in 30 (16.3%) patients post-operatively. Chromic gut suture was used in 53.3% of the patients who experienced hypersensitivity. Patients who had chromic catgut used in their surgery were 2.82 times more likely to develop hypersensitivity than patients who did not have chromic gut used (p = 0.0015). If a patient had a nerve repaired and chromic gut sutured used, they were 6.50 times more likely to develop hypersensitivity (p < 0.0001).ConclusionSurgeons should be aware that this data indicates that suture choice in hand trauma patients can greatly impact the risk of the patient developing hypersensitivity.Level of evidence: Level IV, risk/prognostic study.

Oral Rehabilitation of an Adult Cleft Palate Patient with Zygomatic Implant-supported Obturator Prosthesis: A Case Report

IntroductionWith advancement in medical services and their accessibility across the country, as well as growing awareness among the patient population, it is rare to find an adult with an untreated cleft lip and/or palate nowadays. Treatment of these patients to restore form and function can be challenging, often yielding less-than-satisfactory outcomes. In current literature, there have been case reports of patients with atrophic maxilla or severe maxillary defects after oncologic resections, where zygomatic implants have been utilized for fabrication of a fixed maxillary prosthesis.Here, the authors present a case of an adult cleft palate patient treated with a zygomatic implant-supported removable obturator prosthesis, which has not yet been reported in literature. BackgroundThe patient is a 66-year-old female who presented to the University of Maryland Oral & Maxillofacial Surgery Associates in 2016 for management of an untreated bilateral cleft palate. She had been wearing an obturator for several years prior that had slowly lost retention over time due to ridge resorption. Patient had undergone multiple procedures for placement of endosseous implants to support a fixed prosthesis as well as sinus lift surgeries, all of which had failed. She had 1 clinically osseointegrated implant in the right maxilla that was restorable. The patient did not wish to pursue any extensive surgical interventions, so after consultation with a maxillofacial prosthodontist at the authors' unit, the decision was made to pursue a zygomatic implant-supported obturator prosthesis fabrication to restore the patient's form and function. Surgical techniqueThe patient underwent general anesthesia induction and nasotracheal intubation. Mucoperiosteal flaps were reflected bilaterally in the oral cavity along the maxillary alveolar ridge, extending up to orbital rims and laterally over the zygomatic eminence. Sinus windows were created for visualization of twist drills. Osteotomies were created in the zygomatic bone using NobelBiocare protocol, and 2 35mm implants were inserted in the left zygoma, and a 45mm implant was placed on the right-side mesial to the existing endosseous implant. Left maxillary palatal side was grafted with particulate bone, and cover screws were placed. Soft-tissue closure was with 3-0 chromic gut sutures. Implants were buried for 6 months, then uncovered and restored using locator bars to connect implants in each alveolar segments, which would, in turn, support the maxillary obturator. ResultsThe patient has been compliant with follow-ups and last seen in August 2020. She reported good function without any nasal regurgitation and was satisfied with retention and stability of her prosthesis. On examination of her oral cavity after obturator removal, the tissues were healthy-appearing, and the locator housings were evaluated and found to be in good shape and retentive. Radiographically, the implants were stable without signs of bone loss. ConclusionThe authors have found that zygomatic implants can be utilized as an alternative to support an obturator prosthesis. However, given lack of long-term follow-up in literature, some reservations must be expressed in its use, especially when other predictable alternatives are available.

Randomized Controlled Trial Comparing Nylon and Chromic Gut Sutures After Minor Hand Surgery

We sought to compare overall satisfaction with treatment and satisfaction with initial wound healing after closure of office hand and upper extremity surgery wounds using polyamide compared to Chromic gut sutures. We compared 62 patients randomized to polyamide suture closure of an office hand and upper extremity incision (mostly carpal tunnel release and trigger finger release) to 50 patients closed with Chromic gut suture. Patients rated overall treatment satisfaction, satisfaction with initial healing, pain intensity, and upper extremity-specific activity tolerance. Accounting for potential confounding in multivariable linear and logistic regression analysis, we found the following: (1) overall satisfaction with care was unrelated to suture type; (2) satisfaction with initial wound healing and appearance was lower among people with no other comorbidities, but unrelated to suture type; (3) there were no factors independently associated with pain intensity; and (4) excisional biopsy was associated with greater activity tolerance. Our findings suggests that Chromic sutures are a viable alternative to polyamide sutures after office hand surgery, provided that the care team anticipates and develops strategies for concerns that may arise if the sutures take an extended period to fall off. Therapeutic II.

Modified Marionette Technique for Unassisted In-Office Access to the Submandibular Duct.

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Inferior Meatus Mucosal Flap for Septal Reconstruction and Resurfacing After Nasoseptal Flap Harvest.

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The Therapeutic Effectiveness of Full Spectrum Hemp Oil Using a Chronic Neuropathic Pain Model.

Background: Few models exist that can control for placebo and expectancy effects commonly observed in clinical trials measuring ‘Cannabis’ pharmacodynamics. We used the Foramen Rotundum Inflammatory Constriction Trigeminal Infraorbital Nerve injury (FRICT-ION) model to measure the effect of “full-spectrum” whole plant extracted hemp oil on chronic neuropathic pain sensitivity in mice. Methods: Male BALBc mice were submitted to the FRICT-ION chronic neuropathic pain model with oral insertion through an incision in the buccal/cheek crease of 3 mm of chromic gut suture (4-0). The suture, wedged along the V2 trigeminal nerve branch, creates a continuous irritation that develops into secondary mechanical hypersensitivity on the snout. Von Frey filament stimuli on the mouse whisker pad was used to assess the mechanical pain threshold from 0–6 h following dosing among animals (n = 6) exposed to 5 μL of whole plant extracted hemp oil combined with a peanut butter vehicle (0.138 mg/kg), the vehicle alone (n = 3) 7 weeks post-surgery, or a naïve control condition (n = 3). Results: Mechanical allodynia was alleviated within 1 h (d = 2.50, p < 0.001) with a peak reversal effect at 4 h (d = 7.21, p < 0.001) and remained significant throughout the 6 h observation window. There was no threshold change on contralateral whisker pad after hemp oil administration, demonstrating the localization of anesthetic response to affected areas. Conclusion: Future research should focus on how whole plant extracted hemp oil affects multi-sensory and cognitive-attentional systems that process pain.

Alterations in mouse spinal cord and sciatic nerve microRNAs after the chronic constriction injury (CCI) model of neuropathic pain

Pain is one of the most common reasons to seek medical attention and chronic pain is a worldwide epidemic. There are currently no relevant biomarkers for the diagnosis of chronic pain, and new therapeutic strategies for chronic pain treatment are desperately needed. The chronic constriction injury (CCI) of the sciatic nerve is a widely used preclinical model of pathological neuropathic pain. Over the past decade, investigators have come to appreciate the many contributions of noncoding RNA including microRNA (miRNA), and other long and short noncoding (nc) RNAs. The development and/or maintenance of chronic pain could be controlled epigenetically through ncRNAs. Here we seek to characterize CNS tissues in a mouse model of neuropathic pain as this may serve to elucidate potential biomarkers relevant to pathological pain in humans. Male C57BL6/J mice (6 CCI and 6 sham procedure) underwent surgery for sciatic nerve ligation with chromic gut sutures. Following 7 days, mechanical allodynia was quantified using the von Frey assay. Mice were then euthanized for collection of spinal cord and sciatic nerve. cDNA was synthesized to 627 unique mature miRNAs from the total RNA. In the CCI mice that displayed mechanical allodynia, 11 and 125 miRNAs were differentially expressed (i.e., greater than 1.5-fold increase or decrease; P < 0.05) in the spinal cord and sciatic nerve, respectively, as compared to sham controls. Among those differentially expressed miRNAs in the sciatic nerve of CCI mice, the following passed the more stringent Bonfferoni correction: miR-138-3p, miR-138-5p and miR-676-3p, reduced and miR-142-5p, increased. Our data support miRNAs as promising therapeutic targets for the treatment of pathological pain.

Effect of Hysterotomy Closure With Polyglactin 910 Versus Chromic Gut Suture on Secondary Cesarean Deliveries [12P

INTRODUCTION: The objective of this was study was to determine if hysterotomy closure with polyglactin 910 (PG) versus chromic gut (CG) suture material is associated with differences in development of adhesions and surgical complications in secondary cesarean deliveries (CD). METHODS: We conducted a 3 year retrospective cohort study and reviewed charts on all women who received a secondary CD. Operative notes were reviewed and charts were separated depending if closure of the hysterotomy was performed with PG or CG. Charts were excluded if at time of primary CD, a double layer closure of hysterotomy, closure of peritoneum and rectus muscle were not performed, or additional procedure was performed. Appropriate IRB approval was obtained. Primary outcomes included operating time, surgical blood loss, and report of “dense” or “extensive” adhesions (DEA) requiring lysis of adhesions and/or enterolysis as a separate procedure. RESULTS: The study included 313 patients, where 181 patients had hysterotomy closures with PG and 132 had closures with CG. Baseline characteristics were not significantly different between groups including previous abdominal surgery. The CG group was associated with lower rates of DEA (19% versus 21%, P=.031) and shorter total operative time (1.1 hours versus 1.9 hours, P=.024). No difference was noted in surgical blood loss or rates of postpartum hemorrhage. After controlling for perceived confounding factors, these differences remained significant. CONCLUSION: In this retrospective study, hysterotomy closures with CG suture were associated with lower rates of reported adhesions and decreased total operative time when compared with PG closures.

Minimally Invasive Oral Surgery Induction of the FRICT-ION Chronic Neuropathic Pain Model.

An easily induced preclinical trigeminal neuropathic nerve injury model is described here for the study of chronic pain, the model acronym FRICT-ION (Foramen Rotundum Inflammatory Constriction Trigeminal InfraOrbital Nerve). In patients, neuropathic pain is thought to be related to vascular alignment or multiple sclerosis along this small trigeminal nerve branch (V2) innervating the maxillary teeth and middle third of the face. With no detectable outward physical signs, the FRICT-ION model is ideal for blinded studies. The acronym FRICT-ION applied relates to the persistence of the trigeminal neuropathic pain model likely due to sliding irritation with normal chewing in the mice. A step-by-step method to induce the mild chronic rodent neuropathic pain model is described here. The surgery is performed orally through a tiny surgical slit inside the cheek crease to align a chromic gut suture irritant along the nerve as it passes into the skull. The model allows testing of non-evoked subjective measures and evoked quantitative mechanical hypersensitivity (allodynia) testing with von Frey filaments through at least 10-14 weeks (100 days). Anxiety and depression behaviors develop within 3-6 weeks relevant to the affective component of chronic pain. While many pain drugs have failed based on testing performed in the acute animal models available, the more stable and easily replicated trigeminal inflammatory compression model is the better suited for understanding both mechanistic and affective components of nerve injury-induced chronic neuropathic pain states as well as the more ideal for preclinical trials of novel non-opioid pain relief therapies.

Which Stitch? Replacing Anecdote with Evidence in Minor Hand Surgery.

Summary:There is currently no consensus on the optimal suture type for palmar skin closure following open carpal tunnel release and trigger finger release. We performed a retrospective analysis of patients in the Palo Alto Veterans Affairs (PAVA) Health Care System who underwent these procedures over a 2-year period to compare 30-day wound outcomes following closure with poliglecaprone 25 (Monocryl), nylon, and chromic gut suture. Out of 312 PAVA cases (133 carpal tunnel release, 179 trigger finger release), incisions closed with Monocryl were significantly less likely to develop dehiscence (Monocryl 2.1%, nylon 10.5%, chromic 10.3%; P = 0.006) and infection (Monocryl 1.6%, nylon 7.4%, chromic 13.8%; P = 0.003), or lead to additional wound-related encounters (Monocryl 8.0%, nylon 16.8%, chromic 24.1%; P = 0.012). On multivariable logistic regression, suture type and diabetes were independent predictors of 30-day wound complications and extra encounters. At PAVA, compared with Monocryl, closures with nylon and chromic were significantly more likely to dehisce and/or become infected [nylon: odds ratio (OR), 5.0; 95% CI, 1.9–13.3 and chromic: OR, 9.3; 95% CI, 2.7–32.4; P = 0.002], and to be associated with an additional encounter (nylon: OR, 2.4; 95% CI, 1.1–5.3 and chromic: OR, 4.5; 95% CI, 1.6–12.9; P = 0.007). This has led to using Monocryl as the standard closure for these cases at PAVA.

Non‐coding RNAs as Markers of Neuropathic Pain

Pain is one of the most common reasons to seek medical attention and chronic pain is a worldwide epidemic. Under some circumstances, incoming protective nociceptive signaling is prolonged leading to clinical manifestations of pathological neuronal signaling. The chronic constriction injury (CCI) of the sciatic nerve is a widely used preclinical model of pathological neuropathic pain. Over the past decade, investigators have come to appreciate the extracellular actions of RNA located within cells such as mRNA, micro (mi) RNA, and other long and short noncoding (nc) RNAs. The development and/or maintenance of chronic pain could be controlled epigenetically through ncRNAs. Here we seek to characterize ncRNAs in blood, sciatic nerve, and spinal cord in a mouse model of neuropathic pain as this may serve to elucidate potential biomarkers relevant to pathological pain in humans. Male C57BL6/J mice (6 CCI and 6 sham procedure) underwent surgery for sciatic nerve ligation with chromic gut sutures. Following 7 days, mechanical allodynia was quantified using the von Frey assay. Mice were then euthanized for collection of spinal cord, sciatic nerve, and blood. cDNA was synthesized to 322 unique mature miRNAs from the total RNA. Of the 627 miRNAs examined, 414 and 376 were detectable (CT ≤ 35) in the spinal column and sciatic nerve, respectively. In the CCI mice that displayed mechanical allodynia, 11 and 126 miRNAs were differentially expressed (i.e., greater than 1.5‐fold increase or decrease; P &lt; 0.05) in the spinal column and sciatic nerve, respectively, as compared to sham controls. Three members of the miR‐183 cluster (miR‐183, miR‐182 and miR‐96) were reduced in both the spinal column and sciatic nerve. Our data support the use of miRNAs as biomarkers to identify subpopulations of patients with neuropathic pain. Further, targeting miRNAs may hold promise for the treatment of pathological pain.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

(346) Manganese Enhanced MRI in Experimental Chronic Trigeminal Neuropathic Pain and Anxiety

A chronic constriction trigeminal nerve injury model (CCI-ION) was utilized for comparisons to healthy naive male rats using manganese-enhanced magnetic resonance imaging. The CCI-ION model was induced by unilaterally placing 2 ties of chromic gut suture around the infraorbital nerve within the orbital cavity. Throughout the study, mechanical sensitivity was tested weekly on the whisker pad, the receptive field of the ION. In week 8 when hypersensitivity was chronic, anxiety-like behavior were assayed using the light-dark place preference and elevated plus maze tests. In week 10, animals were injected with 62mg/kg MgCl2 dissolved in saline 24hrs prior to the scan with a 7-Tesla MRI machine. Animals were anesthetized with 2-2.5% isoflurane, positioned within a small bore quadrature RF coil (inner diameter = 86mm), and a phase array surface coil employed for signal excitation and detection, respectively. Respiration and heart rate were monitored, and body temperature was maintained at 37.0 ± 0.5°C. T1-weighted images were acquired with a fast sequence producing signals (gradient echo) with low flip angles sequence (FLASH). Repetition Time (TR)/Echo Time (TE) = 500 ms/3ms, Field of View (FOV)=3.5cm × 3.5cm, slice thickness=0.5mm, inter-slice distance=0.5mm, number of slice =40, matrix=256 × 256, number of average=21. Within 3wks after CCI-ION model induction, reflexive mechanical hypersensitivity was maximal and persisted until experiment's end. Rats with the chronic pain model displayed anxiety-like behavior, spending significantly more time in the dark chamber and preferentially staying in the closed arm without looking into the open arms of the elevated plus maze. CCI-ION rats had increased MEMRI signals within the anterior cingulate cortex, amygdala, habenula, and thalamus, while signals in the periaqueductal grey, dentate gyrus, pyriform cortex, and ventral tegmental area were not different compared to naive rats. These studies will assist understanding of neuropathic chronic pain associated process and changes in the brain.

Characterization of neuromas in peripheral nerves and their effects on heterotopic bone formation.

The formation of neuromas involves expansion of the cellular components of peripheral nerves. The onset of these disorganized tumors involves activation of sensory nerves and neuroinflammation. Particularly problematic in neuroma is arborization of axons leading to extreme, neuropathic pain. The most common sites for neuroma are the ends of transected nerves following injury; however, this rodent model does not reliably result in neuroma formation. In this study, we established a rodent model of neuroma in which the sciatic nerve was loosely ligated with two chromic gut sutures. This model formed neuromas reliably (∼95%), presumably through activation of the neural inflammatory cascade. Resulting neuromas had a disorganized structure and a significant number of replicating cells. Quantification of changes in perineurial and Schwann cells showed a significant increase in these populations. Immunohistochemical analysis showed the presence of β-tubulin 3 in the rapidly expanding nerve and a decrease in neurofilament heavy chain compared to the normal nerve, suggesting the axons forming a disorganized structure. Measurement of the permeability of the blood–nerve barrier shows that it opened almost immediately and remained open as long as 10 days. Studies using an antagonist of the β3-adrenergic receptor (L-748,337) or cromolyn showed a significant reduction in tumor size and cell expansion as determined by flow cytometry, with an improvement in the animal’s gait detected using a Catwalk system. Previous studies in our laboratory have shown that heterotopic ossification is also a result of the activation of neuroinflammation. Since heterotopic ossification and neuroma often occur together in amputees, they were induced in the same limbs of the study animals. More heterotopic bone was formed in animals with neuromas as compared to those without. These data collectively suggest that perturbation of early neuroinflammation with compounds such as L-748,337 and cromolyn may reduce formation of neuromas.

LFA-1 antagonist (BIRT377) similarly reverses peripheral neuropathic pain in male and female mice with underlying sex divergent peripheral immune proinflammatory phenotypes.

Aim:The majority of preclinical studies investigating aberrant glial-neuroimmune actions underlying neuropathic pain have focused on male rodent models. Recently, studies have shown peripheral immune cells play a more prominent role than glial cells in mediating pathological pain in females. Here, we compared the onset and duration of allodynia in males and females, and the anti-allodynic action of a potentially novel therapeutic drug (BIRT377) that not only antagonizes the action of lymphocyte function-associated antigen-1 (LFA-1) to reduce cell migration in the periphery, but may also directly alter the cellular inflammatory bias.Methods:Male and female mice were subjected to peripheral nerve injury chronic constriction injury (CCI) applying two methods, using either 4–0 or 5–0 chromic gut suture material, to examine potential sex differences in the onset, magnitude and duration of allodynia. Hindpaw sensitivity before and after CCI and application of intravenous BIRT377 was assessed. Peripheral and spinal tissues were analyzed for protein (multiplex electrochemiluminescence technology) and mRNA expression (quantitative real-time PCR). The phenotype of peripheral T cells was determined using flow cytometry.Results:Sex differences in proinflammatory CCL2 and IL-1β and the anti-inflammatory IL-10 were observed from a set of cytokines analyzed. A profound proinflammatory T cell (Th17) response in the periphery and spinal cord was also observed in neuropathic females. BIRT377 reversed pain, reduced IL-1β and TNF, and increased IL-10 and transforming growth factor (TGF)-β1, also an anti-inflammatory cytokine, in both sexes. However, female-derived T cell cytokines are transcriptionally regulated by BIRT377, as demonstrated by reducing proinflammatory IL-17A production with concurrent increases in IL-10, TGF-β1 and the anti-inflammatory regulatory T cell-related factor, FOXP3.Conclusion:This study supports that divergent peripheral immune and neuroimmune responses during neuropathy exists between males and females. Moreover, the modulatory actions of BIRT377 on T cells during neuropathy are predominantly specific to females. These data highlight the necessity of including both sexes for studying drug efficacy and mechanisms of action in preclinical studies and clinical trials.

Простой подход к хирургии сенильного заворота нижних век

Introduction. The everting sutures in the correction of lower eyelid in case of involutional entropion, known since the time of Hippocrates, is a simple and accessible technique. However, the recurrences of lower eyelid entropion occur in 7.3% to 49.3% of cases. In all cases, the everting sutures are applied in a single row and using different materials from the 4/0 chromic gut sutures to the 5/0 monofilament sutures. Purpose. To assess the efficacy of single- and multi-row everting sutures in the correction of lower eyelid involutional entropion using absorbable sutures 6/00 (PGA Resorba®, Germany). Material and methods. The clinical trial included 26 eyelids in 23 patients with involutional entropion of lower eyelids. Patients were assessed 2 weeks and 1,3,6,12 months postoperatively. Results. The average age was 74.13±9.2 years (57-87 years). The entropion of lower eyelid in the moderate degree was diagnosed in 16/26 (61.54%), mild – in 6/26 (23.08%), severe – in 4/26 (15.38%) patients. The Pinch-test value (test for distraction) was 8.12±1.45mm. The vertical excursion of lower eyelid averaged 4.38±1.17mm. All the patients during the examination had a discrepancy between the retractor of the lower eyelid. The mean duration of post-operative follow-up was 10.5±3.1 months (1-12 months). recurrences were detected in 5/23 (21.74%) of patients after single-row of sutures within the 1-year follow-up. Patients who were treated with multi-row eversion sutures had no recurrences. Any complications in the form of inflammatory reactions to the sutures were not detected in all observed patients. Conclusion. The single- and multi-row everting sutures in the correction of lower eyelid involutional entropion using absorbable sutures 6/0 showed their effeciency in the form of a stable position of the eyelid in 78.26% of cases during the entire follow-up period.

Prenatal alcohol exposure is a risk factor for adult neuropathic pain via aberrant neuroimmune function

BackgroundClinical studies show that prenatal alcohol exposure (PAE) results in effects that persist into adulthood. Experimental animal models of moderate PAE demonstrate that young adults with PAE display potentiated sensitivity to light touch, clinically termed allodynia, following sciatic nerve chronic constriction injury (CCI) that coincides with heightened spinal glial, spinal macrophage, and peripheral immune responses. However, basal touch sensitivity and corresponding glial and leukocyte activation are unaltered. Therefore, the current study explored whether the enduring pathological consequences of moderate PAE on sensory processing are unmasked only following secondary neural insult.MethodsIn middle-aged (1 year) Long Evans rats that underwent either prenatal saccharin exposure (control) or moderate PAE, we modified the well-characterized model of sciatic neuropathy, CCI, to study the effects of PAE on neuro-immune responses in adult offspring. Standard CCI manipulation required 4 chromic gut sutures, while a mild version applied a single suture loosely ligated around one sciatic nerve. Spinal glial immunoreactivity was examined using immunohistochemistry. The characterization and functional responses of leukocyte populations were studied using flow cytometry and cell stimulation assays followed by quantification of the proinflammatory cytokines interleukin-1beta (IL-1β) and tumor necrosis factor-alpha (TNF-α). Data were statistically analyzed by ANOVA and unpaired t tests.ResultsThe current report demonstrates that mild CCI generates robust allodynia only in PAE rats, while the pathological effects of PAE following the application of a standard CCI are revealed by enhanced allodynia and elevated spinal glial activation. Additionally, mild CCI increases spinal astrocyte activation but not microglia, suggesting astrocytes play a larger role in PAE-induced susceptibility to aberrant sensory processing. Leukocyte populations from PAE are altered under basal conditions (i.e., prior to secondary insult), as the distribution of leukocyte populations in lymphoid organs and other regions are different from those of controls. Lastly, following in vitro leukocyte stimulation, only PAE augments the immune response to antigen stimulation as assessed by heightened production of TNF-α and IL-1β.ConclusionsThese studies demonstrate PAE may prime spinal astrocytes and peripheral leukocytes that contribute to enduring susceptibility to adult-onset neuropathic pain that is not apparent until a secondary insult later in life.

Quality of Adhesions After Sutured Paramedian vs. Laparoscopic Toggle Abomasopexy in an Ovine Model.

To evaluate adhesions created by abomasopexies using either chromic gut or polydioxanone suture through a right paramedian approach and determine whether a laparoscopic toggle technique is an acceptable alternative to open abomasopexy using an ovine model. Experimental study. Mature ewes (n=30). Ewes received 1 of 3 abomasopexy techniques (n=10): right paramedian approach using chromic gut or polydioxanone, or a laparoscopic toggle technique. After euthanasia 8 weeks postoperatively, adhesions were removed en bloc and adhesion cross-sectional area (width × length) and depth (distance from abdominal wall to abomasum) were measured and given a grade of 0-3 based on the quality of adhesion. Surgical time was recorded and compared for each technique. Significance was set at P≤.05. Abomasopexies performed with either suture material resulted in a significantly larger mean cross-sectional area and higher adhesion grades compared to those performed using the toggle. Width and length of adhesions formed using chromic gut or polydioxanone were not significantly different; however, both were significantly wider and longer than those formed using the toggle. The laparoscopic toggle technique required significantly less surgical time than the sutured techniques. Polydioxanone is as effective as chromic gut suture material in inducing abomasal adhesion formation in our sheep model. The clinical significance of the size and grade of adhesions formed is unknown and requires further investigation before the laparoscopic toggle technique can be recommended as a replacement for paramedian abomasopexy in cattle for the treatment of displaced abomasum.

Evaluating the effects of recombinant human bone morphogenetic protein-2 on pain-associated behaviors in a rat model following implantation near the sciatic nerve.

OBJECTIVE It has been hypothesized that the recombinant human bone morphogenetic protein-2 (rhBMP-2) amplification of the host inflammatory response interacts with nerves in the spine and contributes to the occurrence of new, postoperative complaints of radiculitis. This in vivo rat study was conducted to assess the capacity for rhBMP-2/ACS (rhBMP-2 applied to absorbable collagen sponge [ACS]) to stimulate pain-associated behaviors in the rat chronic constriction injury (CCI) model. METHODS Rats were randomly assigned to one of 14 treatment groups. Half of the animals underwent a sham procedure in which the left sciatic nerve was exposed and manipulated but no ligature was placed (Sham cohort), while the remaining animals had chromic gut sutures tied around the sciatic nerve to induce CCI (CCI cohort). The following test articles were applied to the sciatic nerve in each cohort: saline alone, saline applied to ACS, 0.1 mg/ml rhBMP-2 applied to ACS, or 1.0 mg/ml rhBMP-2 applied to ACS. The ACS was either wrapped around the sciatic nerve or implanted adjacent to the nerve. Thermal withdrawal latency was assessed on Days 7, 14, 21, and 28 postoperatively. Isolated nerves from selected rats in each group were examined and assessed for histopathological changes on Days 3, 7, 14, and 28. RESULTS CCI produced a significant pain behavioral response for all treatment groups at all time points. In the Sham cohort, 0.1 mg/ml rhBMP-2/ACS wrapped around the nerve (WRP) decreased thermal withdrawal on Day 28, and 1.0 mg/ml rhBMP-2/ACS placed adjacent to the nerve (ADJ) decreased thermal withdrawal on Days 21 and 28. Conversely, in the CCI cohort, 0.1 mg/ml rhBMP-2/ACS ADJ increased thermal withdrawal latencies on Day 7; 1.0 mg/ml rhBMP-2/ACS ADJ increased thermal withdrawal latencies on Day 7; and 1.0 mg/ml rhBMP-2/ACS WRP increased thermal withdrawal on Days 7 and 14. Histologically, the effect of rhBMP-2 on nerve inflammation was unclear, as inflammatory cell infiltration was similar in the rhBMP-2/ACS and saline/ACS groups. rhBMP-2 was variably associated with bone formation within the epineurium at 14 days, and more prevalently at 28 days, with no clear relationship between dose or ACS positioning. CONCLUSIONS In this study, rhBMP-2/ACS did not appear to induce pain independent of grossly visible ectopic bone formation. At the earliest time points, rhBMP-2 appeared to have a neuroprotective effect as evidenced by decreased pain exhibited by the rhBMP-2-treated animals in the CCI cohort, but this effect diminished over time, and by Day 28, the pain behavioral responses in the rhBMP-2-treated group were comparable to those in the group in which saline was applied to the nerve. In the Sham cohort, there was a dose-independent induction of pain at later time points, presumably due to new bone formation mechanically irritating the nerve. Histological examination revealed nerve lesions that appeared to be caused by mechanical trauma associated with surgical manipulation of the nerve during placement of the ACS and/or CCI sutures.

Tissue reactivity and suture handling characteristics of "jimat" against silk and chromic gut in cat thigh muscle: A comparative study.

Aim:This study was conducted to evaluate and compare the tissue reactivity and suture handling characteristics of chromic gut, silk, and ‘jimat’ suture materials in cat thigh muscle.Materials and Methods:This experimental study was conducted from November, 2013 to April, 2014 in Kombolcha Animal Diseases Survey, Research and Diagnostic Laboratory, Kombolcha, Ethiopia. A total of 36 local breed male cats were randomly assigned into chromic gut, silk, and “jimat” groups of 12 cats each as A, B, and C, respectively. The hind leg muscle biceps femoris was incised and sutured with suture materials according to their groups. The muscle samples with its suture were collected at six different days interval i.e. 1, 3, 7, 14, 21, and 28 and processed histopathologically to assess the degree of leukocytic infiltration and fibrous and granulation tissue formation (GTF). In addition, all suture materials were evaluated intraoperatively about their handling characteristics, by rating the precision of knot tying, square knot positioning, and resistance to knot slippage. The statistical analysis was done with two-way ANOVA, Kruskal–Wallis, and Chi-square tests.Results:The histopathology showed that “jimat” thread (2.4±1.2) had produced least leukocytic infiltration than chromic gut (4.5±1.9) and silk (4.3±1.5) sutures during the study period. Higher GTF was seen at day 3 (6 [100%]), 7 (6 [100%]) and day 14 (4 [66.7%]) in all sutures, whereas “jimat” showed significantly (p<0.05) higher fibrous tissue formation (10 [83.3%]) than others. Moreover, “jimat” suture had equal suture handling characteristics (p>0.05) with both chromic gut and silk.Conclusion:The result indicated that a single strand “jimat” thread appears to be the most satisfactory suture material as regards to both tissue reaction and suture handling characteristics for skeletal muscle approximation in cats and provided that studies on its carcinogenic effects should be done.