Gate control of sensory neurotransmission in peripheral ganglia by proprioceptive sensory neurons

Melzak and Wall's gate control theory proposed that innocuous input into the dorsal horn of the spinal cord represses pain-inducing nociceptive input. Here we show that input from proprioceptive parvalbumin-expressing sensory neurons tonically represses nociceptor activation within dorsal root ganglia. Deletion of parvalbumin-positive sensory neurons leads to enhanced nociceptor activity measured with GCaMP3, increased input into wide dynamic range neurons of the spinal cord and increased acute and spontaneous pain behaviour, as well as potentiated innocuous sensation. Parvalbumin-positive sensory neurons express the enzymes and transporters necessary to produce vesicular GABA that is known to be released from depolarized somata. These observations support the view that gate control mechanisms occur peripherally within dorsal root ganglia

The determination of apoptosis rates on articular cartilages of ovariectomized rats with and without alendronate treatment

Osteoporosis (OP) is a major health problem characterized by compromised bone strength. Osteoarthritis (OA) is a joint disease that progresses slowly and is characterized by breakdown of the cartilage matrix. Alendronate (ALN), a nitrogencontaining bisphosphonate (BIS), inhibits bone loss and increases bone mineralization, and has been used clinically for the treatment of OP. It is still controversial whether BIS is effective in inhibiting the progression of OA. Chondrocyte apoptosis has been described in both human and experimentally induced OA models. In our study we aimed to detect whether ALN could protect articular cartilage from degeneration and reduce apoptosis rates in experimentally OA induced rats. For this rats were ovariectomized (ovex), nine weeks after operation rats were injected 30 μg/kg/week ALN subcutaneously for six weeks. After six weeks articular cartilages were obtained. We did Safranin O staining and Mankin and Pritzker scorings to evaluate degeneration and investigated the expressions of p53, cleaved caspase 3, Poly ADP-ribose (PAR), Poly ADP-ribose polymerase 1 (PARP 1), and applied TUNEL technique to determine apoptotis rates. We found a significant decrease in glycosaminoglycan (GAG) amount and increased apoptosis which indicates damage on articular cartilages of ovex rats. GAG amount was higher and apoptosis rate was lower on articular cartilages of ALN treated ovex rats compared to the ovex group. In contrary to studies showing that early ALN treatment has a protective effect, our study shows late ALN treatment has a chondroprotective effect on articular cartilage since we treated rats nine weeks after ovariectom

Stem cells combined 3D electrospun nanofibrous and macrochannelled matrices: a preliminary approach in repair of rat cranial bones

Bolgen, Nimet/0000-0003-3162-0803; Meydanli, E. Elif Guzel/0000-0001-9072-3322; Cetinkaya, Duygu Uckan/0000-0003-3593-6493; KILIC, Emine/0000-0003-2984-7638; Weeks, Jason/0000-0001-5537-6927WOS: 000463175200003PubMed: 30942631Repair of cranial bone defects is an important problem in the clinical area. The use of scaffolds combined with stem cells has become a focus in the reconstruction of critical-sized bone defects. Electrospinning became a very attracting method in the preparation of tissue engineering scaffolds in the last decade, due to the unique nanofibrous structure of the electrospun matrices. However, they have a limitation for three dimensional (3D) applications, due to their two-dimensional structure and pore size which is smaller than a cellular diameter which cannot allow cell migration within the structure. In this study, electrospun poly(epsilon-caprolactone) (PCL) membranes were spirally wounded to prepare 3D matrices composed of nanofibers and macrochannels. Mesenchymal stromal/stem cells were injected inside the scaffolds after the constructs were implanted in the cranial bone defects in rats. New bone formation, vascularisation and intramembranous ossification of the critical size calvarial defect were accelerated by using mesenchymal stem cells combined 3D spiral-wounded electrospun matrices.Turkish Academy of SciencesTurkish Academy of SciencesThis study was performed in the context of the EU-FP6-NoE Expertissues Project. Erhan Piskin is supported by Turkish Academy of Sciences as a Honorary Member. This study was a part of PhD thesis of smail Alper isoglu. The thesis was supervised by Erhan Piskin

Retrospective Multivariate Analysis of Data from Children with Suspected Appendicitis: A New Tool for Diagnosis

Background. Decision-making for management may sometimes be difficult in acute appendicitis (AA). Various diagnostic scoring systems exist, but their sensitivity and specificity rates are far from ideal. In this study, the determination of the predictors and the effect of radiological data and developing a new scoring system were aimed. Methods. Medical records of patients who were hospitalized for AA between February 2012 and October 2016 were retrospectively reviewed. All data were compared between patients with and without appendicitis. The multivariate analysis was performed to define significant variables and to examine the sensitivity and specificity of each group of predictors including radiological data. A new scoring system (NSS) was formed and was compared with two existing scoring systems: pediatric appendicitis score (PAS) and Alvarado scoring system (ASS) by using reclassification method. Results. Negative appendectomy rate was 11.3%. Statistical analysis identified 21 independently significant variables. The heel drop test had the highest odds ratio. Sensitivity and specificity rates of clinical predictors were 84.6% and 94.8%, respectively. Radiological predictors increased the sensitivity rate to 86.9%. Sensitivity and specificity rates for PAS, ASS, and NSS were 86.8% and 83.9%, 84.7% and 81.6%, and 96.8% and 95.6%, respectively. The “re-assessed negative appendectomy rate” was 6.2% and false positive results were remarkably more common in patients with duration of symptoms less than 24 hours. Conclusion. Radiological data improves the accuracy of diagnosis. Containing detailed clinical and radiological data, NSS performs superiorly to PAS and ASS, regarding sensitivity and specificity without any age limitation. The efficiency of NSS may be enhanced by determining different predictors for different phases of the inflammatory process

Stem Cells Combined 3D Electrospun Nanofibrous And Macrochannelled Matrices: A Preliminary Approach In Repair Of Rat Cranial Bones

Repair of cranial bone defects is an important problem in the clinical area. The use of scaffolds combined with stem cells has become a focus in the reconstruction of critical-sized bone defects. Electrospinning became a very attracting method in the preparation of tissue engineering scaffolds in the last decade, due to the unique nanofibrous structure of the electrospun matrices. However, they have a limitation for three dimensional (3D) applications, due to their two-dimensional structure and pore size which is smaller than a cellular diameter which cannot allow cell migration within the structure. In this study, electrospun poly(epsilon-caprolactone) (PCL) membranes were spirally wounded to prepare 3D matrices composed of nanofibers and macrochannels. Mesenchymal stromal/stem cells were injected inside the scaffolds after the constructs were implanted in the cranial bone defects in rats. New bone formation, vascularisation and intramembranous ossification of the critical size calvarial defect were accelerated by using mesenchymal stem cells combined 3D spiral-wounded electrospun matrices.WoSScopu

Gelatin-Hydroxyapatite Cryogels with Bone Morphogenetic Protein-2 and Transforming Growth Factor Beta-1 for Calvarial Defects

Over recent years, several tissue engineering techniques are used for bone regeneration. In this study gelatin-hydroxyapatite (Gelatin-HA) cryogel scaffolds were used with/without bone morphogenetic protein-2 (BMP-2) and transforming growth factor beta-1 (TGF-beta 1) to heal critical sized bone defects. Release of growth factors from the cryogels were performed up to 28 days in vitro. Moreover, in vivo study were performed by 6 groups and results were evaluated by micro computerized tomography (mu-CT) and histology on 2 months and 4 months after surgery. Gene expression studies were also performed on 2 weeks and 4 weeks after surgery. Collagen type I (Col I), alkaline phosphatase (ALP) and osteocalcin (OSC) gene expression levels were analyzed. According to histology and mu-CT results, there was a significant bone healing in the BMP-2 containing gelatin-HA cryogel group (Group I) as compared to other groups except autograft applied group (Group IV). Moreover, significant increases were observed for Col I, ALP and OSC in Group I and Group IV. However there was no significant increase in the group of BMP-2 and TGF-beta 1 applied together (Group II). The results reveal that combination of gelatin-HA cryogels with BMP-2 is a promising candidate for healing in critical sized craniofacial bone defects