Resistance of Primary Photosynthesis to Photoinhibition in Antarctic Lichen Xanthoria elegans: Photoprotective Mechanisms Activated during a Short Period of High Light Stress.

The Antarctic lichen, Xanthoria elegans, in its hydrated state has several physiological mechanisms to cope with high light effects on the photosynthetic processes of its photobionts. We aim to investigate the changes in primary photochemical processes of photosystem II in response to a short-term photoinhibitory treatment. Several chlorophyll a fluorescence techniques: (1) slow Kautsky kinetics supplemented with quenching mechanism analysis; (2) light response curves of photosynthetic electron transport (ETR); and (3) response curves of non-photochemical quenching (NPQ) were used in order to evaluate the phenomenon of photoinhibition of photosynthesis and its consequent recovery. Our findings suggest that X. elegans copes well with short-term high light (HL) stress due to effective photoprotective mechanisms that are activated during the photoinhibitory treatment. The investigations of quenching mechanisms revealed that photoinhibitory quenching (qIt) was a major non-photochemical quenching in HL-treated X. elegans; qIt relaxed rapidly and returned to pre-photoinhibition levels after a 120 min recovery. We conclude that the Antarctic lichen species X. elegans exhibits a high degree of photoinhibition resistance and effective non-photochemical quenching mechanisms. This photoprotective mechanism may help it survive even repeated periods of high light during the early austral summer season, when lichens are moist and physiologically active.

Can injection of adipose stem cells to non-union zone increase bone union? Experimental rat study.

OBJECTIVES: This study aims to evaluate the effects of local adipose stem cell injection on non-union and diabetic non-union of rat femurs. MATERIALS AND METHODS: Forty-eight female Wistar albino rats (weighing mean 200 g and aged 8 weeks) were used in this study. The rats were divided into six groups. Group 1 was chosen as a reference for receptor activator of nuclear factor-kappa (κ) B (RANK), receptor activator of nuclear factor-κ B ligand (RANKL) and osteoprotegerin (OPG) genes and no femur osteotomy was performed in this group. Group 2 underwent femur osteotomy, the osteotomy was fixed with a 1.5 mm K-wire as retrograde from the knee joint, and no gap was left in the osteotomy line. In order to induce non-union, femurs underwent osteotomy fixed with K-wires in groups 3, 4, 5 and 6. In addition, the osteotomy line was measured as 1.8 mm gap with electronic calipers and the gap was fixed with U staple. Before osteotomy, streptozocin was injected intraperitoneally at a dose of 60 mg/kg in 0.1 mol/L citrate buffer solution (Ph 4.4) in groups 4 and 6, in order to induce diabetes mellitus. Left femur anteroposterior and lateral X-rays were taken 10 weeks after the operation and the union in group 2 and non-union in groups 3, 4, 5, and 6 were confirmed. To see if injection of adipose stem cells into the non-union site increases bone union, 2 mL 0.9% sodium chloride (NaCl) in groups 3 and 4 and 2×106 adipose stem cell in groups 5 and 6 were locally injected into the non-union area with fluoroscopy. Femur X-rays were taken eight weeks after the injection and all rats were sacrificed. Femurs of rats were removed for histopathological and gene expression evaluation. RESULTS: There were significant differences between the groups injected 0.9% NaCI and adipose stem cells in terms of bone healing according to radiological and histopathological evaluations (p<0.05). No statistically significant difference was observed between the groups in terms of gene expression levels. CONCLUSION: According to the results of our study, local adipose stem cell injection has positive radiological and histopathological effects in diabetic and non-diabetic femoral non-unions, independently of RANK, RANKL, or OPG gene expression pathways.

Icariin promotes early and late stages of fracture healing in rats.

OBJECTIVES: This study aims to evaluate the effects of locally applied icariin on bone fracture healing in femur fractured rat model. MATERIALS AND METHODS: The study included 64 male Sprague-Dawley rats (mean age 6 months; weighing, 280-490 g) in eight main study groups. Fracture healing process and level were evaluated with radiography, histopathology and dual energy X-ray absorptiometry to investigate the effects of local administration of icariin at varying doses, which is an exogenous osteo-inductive substance. Activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were measured in the peripheral blood in addition to glutathione (GSH) and myeloperoxidase (MPO) levels to investigate the effects of icariin on the oxidant-antioxidant systems. RESULTS: Radiological bone mineral density measurements and histopathological findings revealed that icariin improved all these parameters in the two healing periods tested. Superoxide dismutase activity decreased in association with local icariin application to the fractured side whereas GPx and GSH increased and MPO remained unchanged. Icariin increased the GPx and GSH levels which are responsible from scavenging hydroxyl radical and hydrogen peroxide. CONCLUSION: Locally administered icariin to the fracture accelerated bone healing by reducing the oxidative stress.

The chondrotoxic and apoptotic effects of levobupivacaine and bupivacaine on the rabbit knee joint / Os efeitos condrotóxicos e apoptóticos de levobupivacaína e bupivacaína na articulação do joelho de coelhos

Abstract Background: A single dose injection or continuous infusion of local anesthetics into the joint space is considered to be a well-defined analgesia technique. The aim of this study was to investigate the chondrotoxic and apoptotic effects of single-dose intra-articular injection of levobupivacaine and bupivacaine on rabbit knee joint tissues. Materials and methods: The animals were allocated into two groups each containing 20 rabbits. 0.5% levobupivacaine (Group L) and 0.5% bupivacaine (Group B) were applied intra-articularly to the left posterior joints of rabbits. At the same time, normal saline was applied to the right posterior leg knee joints of rabbits in both groups and used as a control (Group S). At the end of the 7th and 28th days after the intraarticular injections, ten randomly chosen rabbits in each group were killed by applying intraperitoneal thiopental. Sections of cartilage tissue samples were stained for light microscopic examinations and the TUNEL method was used to investigate apoptotic cells. Results: As a result of immunofluorescence microscopic examination, the number of apoptotic cells in Group B at day 7 and day 28 were both significantly higher than Group L and S (p < 0.05). Also, the number of apoptotic cells in Group L at day 7 and day 28 were both significantly higher than Group S (p < 0.05). Conclusions: We found that bupivacaine is more chondrotoxic than other anesthetic agent and increases the number of apoptotic cells. These results indicated that bupivacaine caused high chondrotoxic damage and it led to more apoptotic activation than levobupivacaine.

Resumo Justificativa: Uma injeção em dose única ou infusão contínua de anestésicos locais no espaço articular é considerada uma técnica de analgesia bem definida. O objetivo deste estudo foi investigar os efeitos condrotóxicos e apoptóticos da injeção intra-articular com dose única de levobupivacaína e bupivacaína em tecidos articulares do joelho de coelho. Material e métodos: Os animais foram alocados em dois grupos, cada um contendo 20 coelhos. Levobupivacaína a 0,5% (Grupo L) e bupivacaína a 0,5% (Grupo B) foram aplicadas intra-articularmente nas articulações posteriores esquerdas de coelhos. Ao mesmo tempo, solução salina normal foi aplicada nas articulações do joelho da perna posterior direita de coelhos em ambos os grupos e usada como controle (Grupo S). Ao fim do 7° e 28° dias após as injeções intra-articulares, 10 coelhos escolhidos aleatoriamente em cada grupo foram mortos por aplicação de tiopental intraperitoneal. Seções de amostras de tecido cartilaginoso foram coradas para exames de microscopia de luz, e o método TUNEL foi usado para investigar células apoptóticas. Resultados: Como resultado do exame microscópico de imunofluorescência nos dias 7 e 28, o número de células apoptóticas no Grupo B foi significativamente maior que nos grupos L e S (p < 0,05). Além disso, o número de células apoptóticas nos dias 7 e 28 foi significativamente maior no Grupo L do que no Grupo S (p < 0,05). Conclusões: Demonstramos que a bupivacaína é mais condrotóxica do que o outro agente anestésico e aumenta o número de células apoptóticas. Esses resultados indicaram que a bupivacaína causou intensa lesão condrotóxica e levou a uma ativação apoptótica maior do que a levobupivacaína.

[The chondrotoxic and apoptotic effects of levobupivacaine and bupivacaine on the rabbit knee joint]. / Os efeitos condrotóxicos e apoptóticos de levobupivacaína e bupivacaína na articulação do joelho de coelhos.

BACKGROUND: A single dose injection or continuous infusion of local anesthetics into the joint space is considered to be a well-defined analgesia technique. The aim of this study was to investigate the chondrotoxic and apoptotic effects of single-dose intra-articular injection of levobupivacaine and bupivacaine on rabbit knee joint tissues. MATERIALS AND METHODS: The animals were allocated into two groups each containing 20 rabbits. 0.5% levobupivacaine (Group L) and 0.5% bupivacaine (Group B) were applied intra-articularly to the left posterior joints of rabbits. At the same time, normal saline was applied to the right posterior leg knee joints of rabbits in both groups and used as a control (Group S). At the end of the 7th and 28th days after the intraarticular injections, ten randomly chosen rabbits in each group were killed by applying intraperitoneal thiopental. Sections of cartilage tissue samples were stained for light microscopic examinations and the TUNEL method was used to investigate apoptotic cells. RESULTS: As a result of immunofluorescence microscopic examination, the number of apoptotic cells in Group B at day 7 and day 28 were both significantly higher than Group L and S (p<0.05). Also, the number of apoptotic cells in Group L at day 7 and day 28 were both significantly higher than Group S (p<0.05). CONCLUSIONS: We found that bupivacaine is more chondrotoxic than other anesthetic agent and increases the number of apoptotic cells. These results indicated that bupivacaine caused high chondrotoxic damage and it led to more apoptotic activation than levobupivacaine.

Characterisation of α-chitin extracted from a lichenised fungus species Xanthoria parietina.

Lichens are symbiotic associations formed mainly by ascomycete fungi and green algae or cyanobacteria. The presence of chitin in the fungal cell wall has been revealed by previous studies. Considering the presence of fungi in the lichens, this work determines the presence of chitin in a cosmopolitan lichen species Xanthoria parietina. In this study, chitin was derived from a lichen species for the first time and its physicochemical properties were determined by Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy and elemental analysis. The dry weight chitin content of X. parietina was 4.23%, and this chitin was in the α-form. The crystalline index value of the lichen chitin was calculated as 70.1%. The chitin from X. parietina had a smooth surface.

Mid-term results of the elastic intramedullary nailing in paediatric long bone shaft fractures: a prospective study of 102 cases.

The aim of this study was to evaluate the mid-term results of a large series of paediatric patients with long bone shaft fractures who were treated with elastic intramedullary nailing. Between November 2009 and November 2010, 108 long bone shaft fractures in 102 patients were treated with elastic intramedullary nails. The number of nails used, admission time, nail diameter/medullary canal diameter ratio of the nontraumatized extremity, weeks until radiological consolidation, weeks until full weight bearing for the femur and tibia shaft fractures, weeks until the nails were removed, number of radiographs from the diagnosis time to the removal time of nail(s), clinical complications and radiological results were recorded; the union rate, time to union, nonunion, delayed union, malrotation, malalignment, follow-up time and functional outcomes (Flynn outcome scoring) were also recorded. The mean follow-up time was 22.2 (14-30) months. The mean age of the patients was 9.6 (6-15) years for all cases. The mean nail removal time for all cases was 19.2 (17-29) weeks. Eighteen patients developed complications: six had insufficient reductions; two had refractures; four developed a deep infection; one had delayed union that needed revision; two had lower extremity length discrepancies of more than 15 mm; and three had skin impingements. The mean admission time was 19 (6-32) h; the mean number of radiographs from the diagnosis time to the removal time of nail(s) was 14 (8-20) for each fracture. All patients showed excellent or satisfactory results according to Flynn's criteria. The mean time to full weight bearing for the femur and tibia shaft fractures was 62.4 (52-88) days. A nail diameter/medullary canal diameter ratio of over 0.4 showed good results; short union time, less lower extremity length discrepancy and less malalignment were recorded. When patients were informed about possible complications as well as the advantages, almost all chose the operative approach. According to our experience and opinion, elastic intramedullary nailing is the best choice for diaphyseal fractures in children with skeletal immaturity compared with other surgical choices such as osteosynthesis with a plate.

Intrapelvic pin migration after Salter innominate osteotomy and laparoscopic removal: a case report.

Although there are many methods for the treatment of developmental dysplasia of the hip, Salter innominate osteotomy is a surgical technique presently used successfully worldwide. However, several complications can be found after Salter innominate osteotomy. Kirschner (K) wire migration into the pelvic cavity is not a common occurrence and is also rarely reported in the literature. Here, we report the case of a patient who was admitted to the emergency department of our hospital with acute abdominal pain because of K wire migration into the pelvis. We recommend bending the proximal end of the K wires or using threaded K wires to prevent this complication.

Closed reduction and fixation of locked symphysis pubis using tubular external fixator: a case report.

Locked symphysis pubis is a kind of pelvic injury in which one pubic bone is jammed in the back of the other or opposite the obturator foramen following lateral compression forces. In this article, we present a 31-year-old female case of locked symphysis pubis which was treated by closed reduction using tubular external fixator. We believe that tubular external fixators are useful devices to perform closed reduction maneuvers for locked pelvic injuries and also help to reduce the need for open reduction and internal implant usage.

Fondaparinux versus nadroparin for prevention of venous thromboembolism after elective hip and knee arthroplasty.

OBJECTIVE: To evaluate the efficacy and safety of fondaparinux compared with nadroparin for prevention of venous thromboembolism after arthroplasty. PATIENTS AND METHODS: One hundred fifteen patients were randomized into 2 treatment groups. Patients were given fondaparinux in Group I and nadroparin in Group II. Measurements were performed on Days 1, 5, and 21. The wound area was assessed with a subjective visual analog scale. RESULTS: The blood counts, clinical biochemical tests, and coagulation tests (ie, thrombin time, partial thromboplastin time, activated partial thromboplastin time, fibrinogen, prothrombin time-International Normalized Ratio, and antithrombin III activity) did not show statistically significant differences between Group I and Group II. In both study groups, anti-factor Xa activities increased significantly on the fifth and 21st day. The scores of the subjective visual analog scale showed significance on Day 21. CONCLUSIONS: Our results confirm the safety and efficacy of both fondaparinux and nadroparin for prophylaxis after major orthopedic surgery.

Congenital total absence of the quadriceps muscle and patella: a case report with computed tomography scan and three-dimensional reconstructions.

In this study, we present three-dimensional computed tomography (CT) scan image findings of a case with congenital total absence of the quadriceps muscle and patella and partial absence of the sartorius muscle, which caused fixed flexion contracture of the knee joint. Physical examination, radiography, three-dimensional CT scan, and chromosome analysis of the patient were done. On physical examination, the knee joint was at 85 degree fixed flexion contracture. Radiographic views demonstrated soft tissue defects around left femur. Chromosome analysis was normal. CT scan showed total absence of the quadriceps femoris muscle and patella. Congenital absence of the extensor mechanism and patella are very rare anomalies. This case differed from other patellar aplasia or dysplasia syndromes with the presence of fixed flexion knee contracture and aplasia of the extensor mechanism.

An unusual initial presentation of Proteus syndrome: macrosyndactyly.

Proteus syndrome is a complex disorder characterized by a wide variety of deformities including macrodactyly. In the present report, we present a case with complex macrosyndactyly in his hand. The patient was surgically treated. However, he admitted with lymphangiomas on his body during the follow-up period, leading to the diagnosis of Proteus syndrome. This article discusses the differential diagnosis of Proteus syndrome and the treatment methods used for macrodactyly along with the presentation of the case.

Effect of intraarticular propolis in an experimental septic arthritis model.

To evaluate the efficacy and safety of intraarticular propolis compared with systemic antibiotic treatment in an experimental septic arthritis model. Thirty-two rabbits were infected intraarticularly by Staphylococcus aureus. The rabbits were randomly divided into four groups, including a control group and three experimental groups. Drainage was the only procedure performed in group I (control group). The animals were treated with daily intramuscular cefazolin sodium (75 mg/kg) for 7 days in group II. In group III, intraarticular ethanolic extract of propolis (0.5 mg/ml) was injected to the infected knees under sterile conditions on days 7, 14, and 21 after drainage. In group IV, the rabbits received both intramuscular cefazolin sodium as in group II and intraarticular ethanolic extract of propolis as in group III. After 8 weeks, the animals were killed and joint histopathological and scanning electron microscopic parameters were assessed. The best clinical score was obtained in group IV. There were statistically significant differences among all the groups (P<0.05). The highest total score of the histological examination was found in group I and the best total score was obtained in group IV. There were statistically significant differences among the groups when we evaluated the scores of the parameters as loss of chondrocytes, loss of matrix, and pannus in-growth (P<0.05). But there was no significant difference among the groups for the scores of cloning of the chondrocytes (P>0.05). The highest scanning electron microscopy score was found in group I and the best score was obtained in group IV. Our results confirm the safety and efficacy of intraarticular propolis and synergistic effect of propolis when used with cefazolin in an experimental septic arthritis model.

The healing of full-thickness articular cartilage defects in rabbits: successful results with fibroblast growth factor.

OBJECTIVES: This experimental study aims to compare the effects of three techniques; free autogenous periosteal graft, demineralized bone matrix (DBM) and basic fibroblast growth factor (bFGF) combined with periosteal graft on the healing of full thickness joint cartilage defects in rabbits. MATERIALS AND METHODS: This study used 87 adolescent 16 week-old New Zealand rabbits of both sexes, with an approximate weight of 2500-3750 g. The rabbits were randomly divided into four groups including a control group and three experimental groups. Cartilage defects were created in the posterior weight-bearing area of the medial femoral condyles of the rabbits. The surfaces of the osteochondral defects were covered with free autogenous periosteal graft, DBM and periosteal graft combined with bFGF in the experimental groups respectively. The rabbits were sacrificed at 4, 8 and 12 weeks postoperatively. Macroscopic and microscopic evaluations were performed. RESULTS: Periosteal grafts and DBM respond to the repair of cartilage defects in varying degrees. Although the macroscopic evaluation scores were higher in the bFGF group, there was no statistically significant difference between groups (p>0.05). The total scores on the histological grading scale were significantly higher in the bFGF group and control group than the other groups at 4(th) and 8(th) weeks (p<0.05). At the 12(th) week the total score was significantly higher in the bFGF group than the other three groups (p<0.05). CONCLUSION: The application of bFGF promoted regeneration of articular cartilage and led to successful cartilaginous resurfacing of defects within 12 weeks. We suggest that bFGF when combined with periosteal grafts may have excellent repair capacity in the restoration of osteochondral defects.

Melatonin promotes fracture healing in the rat model.

OBJECTIVES: In this study, we investigated the effect of melatonin on fracture healing in the rat tibia model by using biochemical and histopathologic methods. MATERIALS AND METHODS: In this study 80 male Sprague-Dawley rats were randomized into two groups, a control group (Group 1) and melatonin group (Group 2) with eight rats per group according to the day of sacrifice (Days 1, 3, 7, 14 and 28). The fractures were produced by the manual breakage using plate-bending devices, placed at the distal 3(rd) of the right tibia. Group 2 received 30 mg/kg/day melatonin and group 1 1% alcohol in saline 5 ml/kg/day intraperitoneally during the experiment. Plasma Malondialdehyde (MDA) levels, activity of superoxide dismutase (SOD) and myeloperoxidase (MPO) were measured biochemically. The fracture healing was evaluated using a five-point scale defined by Allen et al. RESULTS: Malondialdehyde levels in group 2 decreased at days 3, 7, 14, and 28 compared to control values (p<0.05). Superoxide dismutase activity in group 2 decreased at days 3, 7 and 14, and returned to the 1(st) day value after 28 days. Myeloperoxidase values in group 2 decreased at days 1, 3, and 7 (p<0.001). Histopathological specimens of healed tibias showed two animals with complete cartilaginous union, five with incomplete bony union and one with complete bony union in the group 2. In contrast, in the group 1, six rats showed complete cartilaginous union and two showed incomplete cartilaginous union (p<0.05). CONCLUSION: The administration of melatonin maybe beneficial in suppressing the effects of free oxygen radicals and regulating antioxidant enzyme activity in the fracture healing process.

Biomechanical properties of a new multilocking loop peripheral suture technique for the repair of flexor tendons: a comparative experimental study.

We aimed to evaluate the biomechanical properties of a new multilocking loop peripheral suture technique. For this aim, 40-deep digital flexor tendons of adult male sheep front limb were divided and then repaired using one of the following methods: simple peripheral suture plus 2- or 4-strand Kessler core suture or a new multilocking loop peripheral suture combined with either 2- or 4-strand Kessler core suture. Intact tendons were used as controls. The following biomechanical parameters were tested: ultimate tensile strength, energy to failure, 2-mm gap formation force, stiffness, and mechanism of failure. Regardless of the number of core suture strands, the new technique resulted in greater ultimate tensile strength, energy to failure, 2-mm gap formation force, and stiffness values, compared with simple running peripheral suture. In conclusion, the new multilocking loop peripheral suture technique represents a biomechanically strong and technically suitable method for flexor tendon repair.

Short- and mid-term results of plica excision in patients with mediopatellar plica and associated cartilage degeneration.

This study aimed to evaluate the short- and mid-term results of plica excision in patients with mediopatellar plica and associated cartilage degeneration. Seventy-six surgically treated patients with mediopatellar plica and associated cartilage degeneration at medial femoral condyle (MFC) and/or medial pole of patella were included. Patients were evaluated at baseline, at 6 weeks and 6 months after the operation for their clinical outcomes and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores. The frequency of all signs and symptoms, including all pain parameters, and WOMAC scores were significantly improved compared to baseline, at 6 weeks and 6 months after the operation (P < 0.017). Based on mean WOMAC scores, results of most patients were rated as excellent both at 6 weeks (88%) and at 6 months (94%). Surgical excision of mediopatellar plica associated with cartilage degeneration appears to result in substantial clinical improvement, thus it represents an effective treatment modality.

Assessment of air pollution genotoxicity by molecular markers in the exposed samples of Pseudevernia furfuracea (L.) Zopf in the province of Kayseri (Central Anatolia).

In living organisms heterogenous air pollutants are considered as a major source of DNA damage. In this study, we aimed to describe the DNA changes in Pseudevernia furfuracea (L.) Zopf samples exposed to pollution at various sites in Kayseri by RAPD (random amplified polymorphic DNA) analysis in order to reveal the pattern of genetic variation influenced by the environmental pollution. The study area is characterized by the presence of numerous industrial activities, such as steel works, glassworks, shipbuilding, and metallurgical, mechanical, chemical and food industries. Control samples were collected from Cat forest (Sivas) and exposed to pollution in dry and wet seasons in the province of Kayseri located in Central Anatolia. Results indicated that heterogeneous pollutants might have contributed to the changes in the band patterns obtained by RAPD analysis, reflecting the occurrence of DNA damage in the control samples.

[Evaluation of visual functions in elderly patients with femoral neck fracture]. / Femur boyun kirigi olan ileri yas olgularda görsel fonksiyonlarin degerlendirilmesi.

OBJECTIVES: We aimed at assessing the visual functions in elderly patients with femoral neck fracture and to compare the results with age-matched controls in this three-year prospective study. PATIENTS AND METHODS: Seventy-one patients with a history of fall related hip fracture (39 females, 32 males; mean age 76.3+/-9.7 years; range 64 to 90 years) and who were diagnosed with femoral neck fracture after direct graphy were treated by means of bipolar partial prosthesis and they were contacted postoperatively or prior to discharge to participate in the study. Visual acuity, depth perception, the presence of cataract in the red reflex were evaluated. A dilated fundus and slit-lamp examination were performed if possible. On completion of the examination, the ophthalmologist documented the causes of any visual impairment found. Control group was comprised of age-matched 40 subjects (22 females, 18 males; mean age 73.2+/-7.6 years; range 62 to 90 years) who applied to ophtalmology clinic for routine examination. RESULTS: The visual acuity was significantly decreased in the patient group as was stereopsis (p<0.05). We found no difference between the study group and the controls when we evaluate the distribution of self reported eye disease and eye disease found on ocular examination. The rate of cases who reported not usually wearing glasses was 35% while it was 5% in the control group. When we evaluate the time since last examination, 38% of cases had not had an eye examination for over four years, as compared with 22.5% of controls. CONCLUSION: This study shows that elderly people should have their eyes tested at least once every two years, refractive errors should be corrected and eye diseases should be treated to decrease the risk of fall-related femoral neck fractures.