The feasibility of ultrasound-guided latex labeling of the anterolateral ligament in anatomical dissection - A cadaveric study.

BACKGROUND: The present study aims to investigate the feasibility of labeling ligaments using ultrasound-guided injections. On formalin-fixed cadavers, the anterolateral ligament was selected and targeted for demonstration. The development of portable ultrasound machines and the ability to connect them to tablets via Bluetooth or WLAN makes it an accessible tool to implement into the anatomical dissection courses in order to associate medical imaging (MRI and ultrasound), anatomical structures and their subsequent dissection. METHODS: 8 formalin fixed human cadavers were used for the ultrasound-guided injections of 1 mL of blue latex into the anterolateral ligament. 8 cadavers were not injected with latex for comparative purposes. The injections were performed by an experienced ultra-sonographer. After approximately 10 months, five dissections were carried out by students during the dissection course and three specimens were dissected by anatomists. RESULTS: The anterolateral ligament was successfully marked and demonstrated in 7 out of 8 cases. In 4 out of 5 cases, the dissection was primarily conducted by students, while in 3 out of 3 cases, it was performed by anatomists. The accuracy was 80 % and 100 %, respectively. CONCLUSION: The present study demonstrated that labeling obscure ligaments, such as the anterolateral ligament, using ultrasound guidance is feasible on formalin-fixed cadavers. It also showed that students can successfully perform the dissections as the structure is highlighted and that the time between injection and dissection (approximately 10 months) has little impact on the outcome. The use of ultrasound in dissection courses should be further encouraged.

Review of ultrasound-guided labeling: exploring its potential in teaching cadaveric ligaments during anatomical dissection courses.

Objectives: This scoping review aimed to give an overview of the existing literature about ultrasound-guided labeling techniques of human cadaver ligaments and tried to work out the possibilities of integrating ultrasound into dissection courses. Methods: A literature review was carried out on the 3rd of January 2023, with relevant studies discovered in the following databases: MEDLINE, EMBASE, CENTRAL, BIOSIS Previews and Web of Science Core Collection. Grey literature was also considered. The reference lists of all relevant papers were scanned. Only ultrasound studies on human cadaver ligaments were included. The included studies' general characteristics and ultrasound-guided approaches to label the ligaments were taken from them and examined. Results: The search found 8899 matches, but only 96 of them met the criteria. The transverse carpal ligament (15.62%) and the annular pulleys (19.79%) were the ligaments that had received the greatest research attention. Twenty-three studies are included in the methodological analysis. Both the marking substrate and the injected volume were diverse. Although 65% of the included studies achieved 100% accuracy using the ultrasound directed labeling approaches. Conclusions: Ultrasound-guided labeling techniques achieve a high accuracy. Therefore, this methodology could be a potential teaching tool for students during the dissection course. But caution is advised in drawing general conclusions because of the small sample sizes and different methodologies in the studies. Future larger-scale research is necessary.

Oligoprotective effect of metformin through the AMPK-dependent on restoration of mitochondrial hemostasis in the cuprizone-induced multiple sclerosis model.

Oxidative stress with mitochondrial defects has a central role in the development and deterioration of Multiple sclerosis (MS). According to new findings of the effects of metformin on mitochondrial function, has attracted a lot of attention. Furthermore, it is suggested that metformin exerts its beneficial influence through AMP-activated protein kinase (AMPK) pathway. In the current study, we investigated the possible protective effects of metformin on oxidative stress and mitochondrial function by activating the AMPK pathway in the cuprizone-induced demyelination. Mice were fed with cuprizone for 6 weeks. Animals simultaneously received metformin. After sacrificing animals, myelinations, and gliosis, changes in transcription factor and biochemical analysis were assessed. Transmission electron microscopy and luxol fast blue staining revealed that the myelinated axons within corpus callosum of cuprizone-induced demyelination animals increased after administration of metformin. Metformin also upregulated the expression of mitochondrial biogenesis genes. Furthermore, the biochemical analysis demonstrated that metformin ameliorated the oxidative stress induced by cuprizone. Immunohistochemistry analysis showed that astrogliosis and microgliosis were decreased after metformin administration while it enhanced the number of oligodendrocytes. Our data implicated that metformin exerts its therapeutic effects on MS by AMPK signaling improved mitochondrial homeostasis and protected oligodendrocytes.

Therapeutic effect of perinatal exogenous melatonin on behavioral and histopathological changes and antioxidative enzymes in neonate mouse model of cortical malformation.

BACKGROUND: Melatonin, which is an antioxidant and neuroprotective agent, can be an effective treatment for neurological disorders. We assessed the effect of melatonin administration on histological changes, antioxidant enzyme levels, and behavioral changes in a neonate mouse model of cortical malformation. MATERIALS AND METHODS: Cortical malformation was induced by two injections of 15 mg/kg methylazoxymethanol (MAM) on gestational day 15 (E15). Pregnant Balb/c mice were randomly divided into the following six groups: Control (CO), Melatonin (MEL), Luzindole (LUZ), MAM, MEL + MAM1 (co-treatment), and MEL + MAM2 (pretreatment). Melatonin was intraperitoneally injected at a dose of 10 mg/kg daily (from E15 until delivery of from E6 for 20 days after delivery). On postnatal day 31, the activity and anxiety of mice were assessed by open field and elevated plus maze tests, respectively. Histopathological changes in the neonate cortex were studied using hematoxylin and eosin staining and neurofilament immunohistochemistry. Enzyme-linked immunosorbent assays were used to measure the activity of nitric oxide (NO), malondialdehyde (MDA), and antioxidant enzymes, including catalase (CAT), super oxide dismutase (SOD), and glutathione peroxidase (GPX). RESULTS: In the behavioral assessment of neonate mice, a significant increase in the crossing activity and decrease in anxiety were recorded in groups treated with MAM plus melatonin. In histological examination, heterotopic, dysmorphic, and ectopic cells, as well as dyslamination, were seen in the MAM and LUZ groups. However, these defects were attenuated in the MAM plus melatonin groups. Significant reductions were recorded in the SOD and GPX levels in the MAM and LUZ groups compared to the control, while the NO level was increased in these groups. Groups that received MAM plus melatonin showed significant increases in the levels of SOD and GPX and a significant decrease in the level of NO, compared to the MAM group. CONCLUSION: Melatonin increased the crossing activity and decreased the anxiety in the treated mice of the neonate mouse model of cortical malformation. Histologically, the administration of exogenous melatonin in pregnant mice and their neonates had a protective effect on the cerebral cortex of neonates. Also, this effect is elicited by decreasing NO and increasing antioxidative enzymes.

Progesterone therapy induces an M1 to M2 switch in microglia phenotype and suppresses NLRP3 inflammasome in a cuprizone-induced demyelination mouse model.

Demyelination of the central nervous system (CNS) has been associated to reactive microglia in neurodegenerative disorders, such as multiple sclerosis (MS). The M1 microglia phenotype plays a pro-inflammatory role while M2 is involved in anti-inflammatory processes in the brain. In this study, CPZ-induced demyelination mouse model was used to investigate the effect of progesterone (PRO) therapy on microglia activation and neuro-inflammation. Results showed that progesterone therapy (CPZ+PRO) decreased neurological behavioral deficits, as demonstrated by significantly decreased escape latencies, in comparison to CPZ mice. In addition, CPZ+PRO caused a significant reduction in the mRNA expression levels of M1-markers (iNOS, CD86, MHC-II and TNF-α) in the corpus callosum region, whereas the expression of M2-markers (Trem-2, CD206, Arg-1 and TGF-ß) was significantly increased, in comparison to CPZ mice. Moreover, CPZ+PRO resulted in a significant decrease in the number of iNOS+ and Iba-1+/iNOS+ cells (M1), whereas TREM-2+ and Iba-1+/TREM-2+ cells (M2) significantly increased, in comparison to CPZ group. Furthermore, CPZ+PRO caused a significant decrease in mRNA and protein expression levels of NLRP3 and IL-18 (~2-fold), in comparison to the CPZ group. Finally, CPZ+PRO therapy was accompanied with reduced levels of demyelination, compared to CPZ, as confirmed by immunofluorescence to myelin basic protein (MBP) and Luxol Fast Blue (LFB) staining, as well as transmission electron microscopy (TEM) analysis. In summary, we reported for the first time that PRO therapy causes polarization of M2 microglia, attenuation of M1 phenotype, and suppression of NLRP3 inflammasome in a CPZ-induced demyelination model of MS.

Cell therapy in spinal cord injury: a mini- reivew.

Spinal cord injury (SCI) is a debilitating disease which leads to progressive functional damages. Because of limited axonal regeneration in the central nervous system, there is no or little recovery expected in the patients. Different cellular and molecular approaches were investigated in SCI animal models. Cellular transplantation of stem cells can potentially replace damaged tissue and provide a suitable microenvironment for axons to regenerate. Here, we reviewed the last approaches applied by our colleagues and others in order to improve axonal regeneration following SCI. We used different types of stem cells via different methods. First, fetal olfactory mucosa, schwann, and bone marrow stromal cells were transplanted into the injury sites in SCI models. In later studies, was applied simultaneous transplantation of stem cells with chondroitinase ABC in SCI models with the aid of nanoparticles. Using these approaches, considerable functional recovery was observed. However, considering some challenges in stem cell therapy such as rejection, infection, and development of a new cancer, our more recent strategy was application of cytokines. We observed a significant improvement in motor function of rats when stromal derived factor-1 was used to attract innate stem cells to the injury site. In conclusion, it seems that co-transplantation of different cells accompanies with other factors like enzymes and growth factors via new delivery systems may yield better results in SCI.