Culture-expanded mesenchymal stem cell sheets enhance extraction-site alveolar bone growth: An animal study.

BACKGROUND AND OBJECTIVES: Impaired bone formation of the buccal alveolar plate after tooth extraction during adolescence increases the difficulty of future implant restoration. This study was undertaken to assess the feasibility and efficacy of transplanting autogenous scaffold-free culture-expanded mesenchymal stem cell (MSC) sheets to the buccal alveolar bone surface to stimulate local bone growth. MATERIAL AND METHODS: Mandibular bone marrow was aspirated from 3-month-old pigs (n = 5), from which MSCs were isolated and culture expanded. Triple-layer MSC sheets were then fabricated using temperature-responsive tissue culture plates. One month after bone marrow aspirations, the same pigs underwent bilateral extraction of mandibular primary molars, immediately followed by transplantation of 3 autogenous triple-layer MSC sheets on to the subperiosteal buccal alveolar surface of 1 randomly chosen side. The contralateral side (control) underwent the same periosteal reflection surgery without receiving MSC sheet transplantation. Six weeks later, the animals were killed and specimens from both sides were immediately harvested for radiographic and histological analysis. Buccal alveolar bone thickness, tissue mineral density (TMD), mineral apposition and bone volume fraction (BV/TV) were quantified and compared between the MSC sheet and control sides using paired t-tests. RESULTS: Triple-layer MSC sheets were reliably fabricated and the majority of cells remained vital before transplantation. The thickness of buccal bone tended to increase with MSC sheet transplantation (P = .18), with 4 of 5 animals showing an average of 1.82 ± 0.73 mm thicker bone on the MSC sheet side than the control side. After being normalized by the TMD of intracortical bone, the TMD of surface cortical bone was 0.5-fold higher on the MSC sheet side than the control side (P < .05). Likewise, the BV/TV measurements of the buccal surface region were also 0.4-fold higher on the MSC sheet side than the control side (P < .05) after being normalized by measurements from the intracortical region. Mineral apposition measurements were not different between the 2 sides. CONCLUSION: Mandibular marrow-derived MSCs can be fabricated into cell sheets and autogenous transplantation of MSC sheets onto the subperiosteal buccal alveolar bone surface at the tooth-extraction site may increase local bone density.

Dental student self-assessment of a medical history competency developed by Oral and Maxillofacial Surgery Faculty.

PURPOSE: To develop a standardized competency exam to evaluate dental student knowledge of patients with complex medical histories. Analysis was performed to determine if there is a difference between dental student self-assessment of the exam compared to oral surgery faculty. The overall goal is to enhance student comprehension of advanced medical patients in the pre-doctoral oral and maxillofacial surgery clinic and make changes based on student responses. METHODS: The exam took place in a simulation laboratory containing two-way mirrors where the student could not see the evaluator. Three standardized patients (trained actors) were given different medical history scenarios to learn prior to the exam. Students were randomly assigned to interview one patient. The graders consisted of senior and junior level faculty. In real time (live) randomized manner, faculty assessed each student using a standardized rubric to assign a score of 1 to 4. Immediately afterwards, students assessed their own performance using the same scale. RESULTS: Students gave themselves significantly higher grades (P < 0.001) on the exam (10.7 ± 0.12) compared to the faculty (9.2 ± 0.17). There was no significant difference in student (P = 0.16) or faculty assessment (P = 0.29) between the three different medical scenarios. There was no significant difference between faculty in assessment of student performances (P = 0.16). CONCLUSION: These results suggested that students overestimated their performance compared to the faculty assessment. This could be due to that students assessed their performance based on memory and self-confidence; that exceeds their expectations. Internal calibration of student performances and faculty grading using standardized criteria may produce more accurate and reliable outcomes in student scoring.

Effect of valproic acid administration during pregnancy on postnatal development of cerebellar cortex and the possible protective role of folic acid.

BACKGROUND: Valproic acid (VPA), one of the most important antiepileptic drugs, proved to be inevitable for epileptic pregnant women to limit the hazards of convulsions on the foetuses and mothers. Periconceptional folic acid supple-mentation was investigated to protect against several birth defects. However, its role against VPA cerebellar toxicity was not properly investigated. The present study was conducted to evaluate the protective effect of folic acid against VPA cerebellar neurotoxicity. MATERIALS AND METHODS: Twenty-four pregnant female albino rats were divided into three groups; group I (control group, did not receive any drugs), group II (given VPA at a dose of 50 mg/kg body weight once daily) and group III (given the same dose of VPA and 400 µg/kg of body weight folic acid once daily). Ten male offspring from each group were sacrificed at two ages: at 2 and 12 weeks after birth. Samples of cerebellar cortex were taken and prepared for light, electron microscopic examination, glial fibrillary acidic protein (GFAP) immunohistochemical study and histomorphometric analysis. RESULTS: The present study confirmed the neurotoxic effect of prenatal VPA on the cerebellar cortex, especially on Purkinje cells. The cells appeared shrunken, reduced in density, disorganised and surrounded by empty haloes. Nuclear damage and axon degeneration in the form of vacuolation, loss of organelles and absence of neurofilaments with myelin sheath depletion were detected. Concomitant supply of folic acid was shown to retain the normal architecture of Purkinje cells with their axons and nuclei. In many animals receiving folic acid, the thickness of all layers of the cortex increased up to that of the control groups, after being markedly reduced in VPA-treated groups. GFAP immunoreaction was also improved against the strong positive gliosis detected in VPA-treated groups. CONCLUSIONS: The present study confirmed the protective role of folic acid against the cerebellar neurotoxic effects of VPA prenatal exposure. It is recommended that folic acid supplements should be given to every epileptic pregnant mother treated with VPA. (Folia Morphol 2018; 77, 2: 201-209).

The role of the adipose tissue-derived mesenchymal stem cells enriched with melatonin in pancreatic cellular regeneration.

BACKGROUND: Adipose tissue-derived mesenchymal stem cells (AD-MSCs) were proved to differentiate into insulin-producing cells (IPCs), but the amount of insulin secreted was relatively low compared to the insulin secreted by mature pancreatic islets. Enrichment of MSCs culture with melatonin (MT) was found to promote cartilage matrix synthesis, osteogenic and neuronal differentiation. Therefore, the present study was conducted to evaluate the potential role of MT pre-treated AD-MSCs in enhancing the treatment and regeneration of the islet cells of Langerhans in rats with diabetes induced by streptozotocin (STZ). MATERIALS AND METHODS: Forty adult male Sprague Dawley albino rats were divided equally into groups; group I (control group), group II (STZ group), group III (STZ + AD-MSCs) and group IV (STZ+MT pre-treated AD-MSCs). Biochemical studies were implemented including measurements of the body weight, fasting blood glucose and serum insulin levels, Interleukin 17 (IL-17) and IL-10. Samples of the pancreas were taken and prepared for light, fluorescent microscopic examination, proliferating cell nuclear antigen and caspase-3 immunohistochemical studies and histomorphometric analysis. RESULTS: The present study confirmed the regenerative and therapeutic effects of AD-MSCs on the pancreatic cells. Concomitant supply of MT to the culture of AD-MSCs, in group IV, was shown to retain the normal architecture of the islet cells of Langerhans. They appeared well-defined and lightly stained, surrounded by classical pancreatic acini and contained a large number of islet cells with vesicular nuclei and prominent nucleoli. Improvement of all the biochemical parameters, in the same group, was demonstrated by increased body weight and serum insulin levels with a decrease in the fasting blood glucose levels. Significant decrease in the pro-inflammatory cytokine; IL-17 and increase in the anti-inflammatory cytokine; IL-10, compared to the STZ group, were also discovered. Significant increase in the proliferating cell nuclear antigen proliferation index, decrease in caspase-3 and increase in PKH26 labelled MSCs area per cent was recorded in the group of AD-MSCs enriched with MT compared to the group of AD-MSCs without MT. CONCLUSIONS: The present study confirmed the potential therapeutic and protective role of MT pre-treated AD-MSCs against the STZ-induced pancreatic islet cells damage. Further studies are recommended to investigate the efficacy of MT and AD-MSCs over longer experimental durations.

Clinical and radiological outcomes of corrective exercises and neuromuscular electrical stimulation in children with flexible flatfeet: A randomized controlled trial.

BACKGROUND: Flexible flatfeet are common among children being scarcely symptomatic requires no specific treatment and resolves spontaneously. However, flexible flatfoot tends to advance and deteriorate overtime and eventually resulting in significant impairments such as plantar fasciitis and patellofemoral pain syndrome. RESEARCH QUESTION: What is the effect of corrective exercises and neuromuscular electrical stimulation in children with flexible flatfeet? METHOD: This is a randomized controlled trial with 72 children, seven to twelve yearsold, randomly assigned to either intervention or control group (36 children for each group) and engaged in a four months (3 sessions/week) of corrective exercise and neuromuscular electrical stimulation or corrective exercise and sham neuromuscular electrical stimulation respectively. Assessments of Staheli's arch index (through foot print), navicular drop (through navicular drop test) and radiographic indexes (through anterior-posterior and medio-lateral X-ray) of both feet were performed before and after the intervention programs. RESULTS: Study groups were comparable with respect to all outcome measures at entry (P > 0.05). Within group comparison showed significant improvements in all measured variables. Further, between groups comparison revealed significant higher improvements (P < 0.05) in right and left feet Staheli's arch index, navicular drop as well as the radiographic indexes in favor of the intervention group. SIGNIFICANCE: Integration of corrective exercises and neuromuscular electrical stimulation is more effective than exercises alone for providing clinical and radiological improvements in children with flexible flatfeet.

Skin manifestations of chronic hepatitis C virus infection in Cairo, Egypt.

We assessed the dermatological manifestations associated with chronic hepatitis C virus (HCV) infection and their association with liver status. Of 155 patients with chronic HCV infection in Cairo, Egypt, 71 (45.8%) had dermatological manifestations: pruritus without evident skin lesions (21.3%), pigmented purpuric eruption (5.2%), aphthous ulcer and lichen planus (3.9% each), leukocytoclastic vasculitis (2.6%), psoriasis (1.9%), tinea versicolor (1.3%) and other conditions (5.8%). Shrunken liver, splenomegaly and ascites were significantly associated with the presence of skin lesions (relative risk 8.0, 2.7 and 1.8 respectively), and shrunken liver was significantly associated with pruritus (relative risk 2.1). Sex was not associated with any of the skin lesions.

The efficacy of a tissue-engineered xenograft in conjunction with sodium hyaluronate carrier in maxillary sinus augmentation: a clinical study.

PepGen P-15 Putty comprises anorganic bovine bone matrix (ABM) coupled with a synthetic cell-binding peptide, suspended in a sodium hyaluronate carrier. The P-15 portion exhibits a similar structure and properties to the cell-binding region of type I collagen. This study was performed to evaluate ABM/P-15 putty as the sole graft in sinus augmentation. Ten patients for whom both a sinus augmentation and two implants were indicated in the posterior maxilla were enrolled. Bone cores were harvested at 8 and 16 weeks, followed by placement of one implant at 8 weeks and the second at 16 weeks. Twenty collected bone cores were evaluated histologically and by micro-computed tomography. Results showed a significant increase (P<0.05) in bone mineral density at 8 weeks (0.70±0.13g/cm(3)) and 16 weeks (0.97±0.08g/cm(3)) in the graft compared to native (control) bone (0.04±0.02g/cm(3)). There was no significant difference (P>0.05) in the percentage bone volume at the two time intervals (PBV 21.14±4.56 at 8 weeks and 26.33±5.60 at 16 weeks). The average increase in bone height at 16 weeks was 10.55±0.53mm. It is concluded that PepGen P-15 Putty is capable of conducting and accelerating new bone formation and can successfully support dental implants.

Synthesis and antimicrobial activities of novel naphtho[2,1-b]pyran, pyrano[2,3-d]pyrimidine and pyrano[3,2-e][1,2,4]triazolo[2,3-c]-pyrimidine derivatives.

The synthesis of new naphtho[1',2':5,6]pyrano[2,3-d]pyrimidines and related heterocycles has been reported. The key intermediate 3-amino-8-bromo-1-(p-methoxyphenyl)-1H-naphtho[2,1-b] pyran-2-carbonitrile (3c) was obtained in one pot synthesis by treating alpha-cyanocinnamonitrile (1c) with 6-bromo-2-naphthol (2). Antimicrobial activity was shown for some of the synthesized compounds.

Kinesio arm taping as prophylaxis against the development of Erb's Engram.

An Erb's Engram is a common debility that develops in recovering children with Erb's palsy. The purpose of this study was to investigate the effect of kinesiotaping over the deltoid and the forearm on the development of proper upper extremity function in children recovering from Erb's palsy. Thirty patients with Erb's palsy participated for 3 months in this study and were equally divided into two groups; control group A and study group B. The two groups received the same designed physical therapy program, while group B along the program, received kinesiotaping over the deltoid and the forearm. The subjects were evaluated, pre and post-treatment, and scored functionally, using the Toronto Active Motion Scale, and objectively, using an EMG device utilized to obtain the percentages of degeneration of the deltoid and the biceps muscles. Post-treatment values of six out of nine measured variables, between the two groups, revealed significant difference in favor of group B. The obtained results strongly support the introduction of kinesiotaping of the deltoid and the forearm as an adjunct to the treatment program of Erb's palsied children.

Skin manifestations of chronic hepatitis C virus infection in Cairo, Egypt

We assessed the dermatological manifestations associated with chronic hepatitis C virus [HCV] infection and their association with liver status. Of 155 patients with chronic HCV infection in Cairo, Egypt, 71 [45.8%] had dermatological manifestations: pruritus without evident skin lesions [21.3%], pigmented purpuric eruption [5.2%], aphthous ulcer and lichen planus [3.9% each], leukocytoclastic vasculitis [2.6%], psoriasis [1.9%], tinea versicolor [1.3%] and other conditions [5.8%]. Shrunken liver, splenomegaly and ascites were significantly associated with the presence of skin lesions [relative risk 8.0, 2.7 and 1.8 respectively], and shrunken liver was significantly associated with pruritus [relative risk 2.1]. Sex was not associated with any of the skin lesions