The role of neural stem cells in regulating glial scar formation and repair

Glial scars are a common pathological occurrence in a variety of central nervous system (CNS) diseases and injuries. They are caused after severe damage and consist of reactive glia that form a barrier around the damaged tissue that leads to a non-permissive microenvironment which prevents proper endogenous regeneration. While there are a number of therapies that are able to address some components of disease, there are none that provide regenerative properties. Within the past decade, neural stem cells (NSCs) have been heavily studied due to their potent anti-inflammatory and reparative capabilities in disease and injury. Exogenously applied NSCs have been found to aid in glial scar healing by reducing inflammation and providing cell replacement. However, endogenous NSCs have also been found to contribute to the reactive environment by different means. Further understanding how NSCs can be leveraged to aid in the resolution of the glial scar is imperative in the use of these cells as regenerative therapies. To do so, humanised 3D model systems have been developed to study the development and maintenance of the glial scar. Herein, we explore the current work on endogenous and exogenous NSCs in the glial scar as well as the novel 3D stem cell–based technologies being used to model this pathology in a dish.

Driving regeneration, instead of healing, in adult mammals: the decisive role of resident macrophages through efferocytosis

Tissue repair after lesion usually leads to scar healing and thus loss of function in adult mammals. In contrast, other adult vertebrates such as amphibians have the ability to regenerate and restore tissue homeostasis after lesion. Understanding the control of the repair outcome is thus a concerning challenge for regenerative medicine. We recently developed a model of induced tissue regeneration in adult mice allowing the comparison of the early steps of regenerative and scar healing processes. By using studies of gain and loss of function, specific cell depletion approaches, and hematopoietic chimeras we demonstrate here that tissue regeneration in adult mammals depends on an early and transient peak of granulocyte producing reactive oxygen species and an efficient efferocytosis specifically by tissue-resident macrophages. These findings highlight key and early cellular pathways able to drive tissue repair towards regeneration in adult mammals.

Tissue Regeneration: The Dark Side of Opioids

Opioids are regarded as among the most effective analgesic drugs and their use for the management of pain is considered standard of care. Despite their systematic administration in the peri-operative period, their impact on tissue repair has been studied mainly in the context of scar healing and is only beginning to be documented in the context of true tissue regeneration. Indeed, in mammals, growing evidence shows that opioids direct tissue repair towards scar healing, with a loss of tissue function, instead of the regenerative process that allows for recovery of both the morphology and function of tissue. Here, we review recent studies that highlight how opioids may prevent a regenerative process by silencing nociceptive nerve activity and a powerful anti-inflammatory effect. These data open up new perspectives for inducing tissue regeneration and argue for opioid-restricted strategies for managing pain associated with tissue injury.

Evaluation of uterine scar healing by transvaginal ultrasound in 607 nonpregnant women with a history of cesarean section

Background Caesarean scar defect (CSD) seriously affects female reproductive health. In this study, we aim to evaluate uterine scar healing by transvaginal ultrasound (TVS) in nonpregnant women with cesarean section (CS) history and to build a predictive model for cesarean scar defects is very necessary. Methods A total of 607 nonpregnant women with previous CS who have transvaginal ultrasound measurements of the thickness of the lower uterine segment. The related clinical data were recorded and analyzed. Results All patients were divided into two groups according to their clinical symptoms: Group A (N = 405) who had no cesarean scar symptoms, and Group B (N = 141) who had cesarean scar symptoms. The difference in frequency of CS, uterine position, detection rate of CSD and the residual muscular layer (TRM) of the CSD were statistically significant between groups; the TRM measurements of the two groups were (mm) 5.39 ± 3.34 versus 3.22 ± 2.33, P < 0.05. All patients were divided into two groups according to whether they had CSDs: Group C (N = 337) who had no CSDs, Group D (N = 209) who had CSDs on ultrasound examination. The differences in frequency of CS, uterine position, TRM between groups were statistically significant (P < 0.05). In the model predicting CSDs by TRM with TVS, the area under the ROC curve was 0.771, the cut-off value was 4.15 mm. The sensitivity and specificity were 87.8% and 71.3%, respectively. Conclusions Patients with no clinical symptoms had a mean TRM on transvaginal ultrasonography of 5.39 ± 3.34 mm, which could be used as a good reference to predict the recovery of patients with CSDs after repair surgery.

Making caesarean myomectomy safe and feasible: a 12 year single center experience

Background: To standardize our protocol of caesarean myomectomy to make it safe and feasible for all patients.Methods: This prospective study was conducted in Aarogya Hospital and test tube baby Centre, Raipur from 1st January 2008 to 1st August 2020. Total 45 patients who had documented fibroid in index pregnancy and consented for the procedure were included. B- Lynch sutures were prophylactically applied in all cases to prevent PPH.Results: Our maximum patients were between the age of 20-30 years (66.67%) and 75.56% were primigravida. 44.45% cases were of intramural fibroids and in 53.34% cases the size of myoma was >5 cm. Malpresentation was seen in 15.56% cases. 62.22% myomas were removed through single incision. 33.33% patients had uneventful second CS with us with excellent scar healing in 93.33% cases. 20% cases had secondary infertility and are advised further evaluation to find cause of infertility.Conclusions: The decision to proceed with elective myomectomy at time of CS should be approached with proper pre-operative evaluation of the patient, thorough counseling for hysterectomy if required, expert team, arrangement of blood and adequate correction of medical factors like anemia, hypertension, and diabetes mellitus. Prophylactic application of B -Lynch sutures in all the cases made a dramatic improvement in tone of uterus which we observed intra operatively.

Evaluation of uterine scar healing by transvaginal ultrasound in 607 nonpregnant women with a history of cesarean section

Background: Caesarean scar defect (CSD) seriously affects female reproductive health. In this study, we aim to evaluate uterine scar healing by transvaginal ultrasound（TVS）in nonpregnant women with cesarean section（CS）history and to build a predictive model for cesarean section defects is very necessary. Methods: A total of 607 nonpregnant women with previous CS who have transvaginal ultrasound measurements of the thickness of the lower uterine segment . The related clinical data were recorded and analyzed. Results: All patients were divided into two groups according to their clinical symptoms: Group A (N=405) who had no cesarean scar symptoms, and Group B (N=141) who had cesarean scar symptoms. The difference in frequency of CS, uterine position, detection rate of CSD and the the residual muscular layer (TRM) of the CSD were statistically significant between groups; the TRM measurements of the two groups were (mm) 5.39±3.34 vs 3.22±2.33, P<0.05.All patients were divided into two groups according to whether they had CSDs: Group C (N=337) who had no CSDs , Group D (N=209) who had CSDs on ultrasound examination. The differences in frequency of CS, uterine position, TRM between groups were statistically significant (P<0.05). In the model predicting CSDs by TRM with TVS, the area under the ROC curve was 0.771, the cut-off value was 4.15 mm. The sensitivity and specificity were 87.8% and 71.3%,respectively.Conclusions: Patients with no clinical symptoms had a mean TRM on transvaginal ultrasonography of 5.39 ± 3.34 mm, which could be used as a good reference to predict the recovery of patients with CSDs after repair surgery.

Double vest lipodermal flaps for depressed facial scars

Introduction Depressed tethered scar is a common problem that can cause emotional, social and behavioural problems, especially when it involves the exposed body parts. Several techniques have been described for treating these depressed scars, but none of these can fulfil the optimal results. Aim Evaluating the aesthetic outcome of using a double vest lipodermal flaps for treating depressed facial scars. Materials and methods The study included 25 patients with depressed facial scars who underwent scar revision. Their mean age was 31 years. Under local anaesthesia, the scarred area was de-epithelialised and double dart lipodermal flaps were used for revision. Visual analogue and Vancouver scar scales were used as subjective and objective parameters of evaluation, respectively. Results All the patients followed up for five to eight months. No complications were observed during the scar healing period. Patients satisfaction according to the visual analogue scale showed an average value of 8. The mean total scale according to the Vancouver scar scale was 2.6. Conclusion The new technique of using double vest lipodermal flaps is simple and offers a promising alternative for revising depressed scars.

Effect of Botulinum Toxin A on Scar Healing after Thyroidectomy: A Prospective Double-blind Randomized Controlled Trial

The persistence of neck scarring is a common concern among patients undergoing thyroidectomy. Botulinum toxin A (BTA (Botox)) has been shown to suppress scar enlargement at the incision site. The objective of this study was to evaluate the effect of intraoperative Botox administration on neck scarring after thyroidectomy. A prospective double-blind randomized clinical trial was performed in patients undergoing conventional thyroidectomy. Forty patients were randomly allocated to a Botox or a control group (both, n = 20). The wound was closed after injection into the platysma muscle of 50 U of Botox diluted in 1 mL of normal saline or 1 mL of saline alone. Skin scars were assessed using the modified Stony Brook Scar Evaluation Scale (SBSES) and Manchester Scar Scale (MSS) at 1, 12, and 24 weeks postoperatively. The SBSES and MSS scores of the Botox group were significantly better than those of the control group (p = 0.034 and p = 0.039). At 24 weeks postoperatively, the SBSES and MSS scores were significantly better in the Botox group (p = 0.006 and p = 0.030). BTA injected into the incision site can suppress postoperative scar formation and thereby improve the cosmetic outcome.