Coexistence of Hermansky-Pudlak syndrome and JAK2V617F-positive essential thrombocythemia.

Hermansky-Pudlak syndrome (HPS) is an autosomal recessive disorder consisting of oculocutaneous albinism, platelet storage pool deficiency, and lysosomal accumulation of ceroid lipofuscin. The storage pool deficiency of HPS is associated with the lack of dense bodies in the platelets, resulting in impaired response in the secondary phase of aggregation. Patients with HPS have normal coagulation tests; however, their bleeding time is usually prolonged despite normal or increased platelet counts. Essential thrombocythemia (ET) is an uncommon condition, with an incidence of approximately 1.1 per 100,000/year, and it is the most common cause of primary thrombocytosis. JAK2V617F positivity can be observed in approximately half of the patients with ET. Bleeding events in ET have usually been associated with acquired von Willebrand syndrome paradoxically occurring when the platelet counts are extremely high. We, herein, present a case with bleeding diathesis diagnosed as having both HPS and JAK2V617F-positive ET.

Comparison of different cryopreservation protocols for human umbilical cord tissue as source of mesenchymal stem cells.

The main purpose of this study is to establish an effective cryopreservation protocol for the umbilical cord tissue as a source of mesenchymal stem cells (MSCs). In this context, it was aimed to use a cryoprotectant that could be an alternative to dimethyl sulfoxide (DMSO) which is commonly used despite the toxic side effects. Therefore, two different cryopreservation solutions were prepared using 10% DMSO and 10% 1,2 propanediol (PrOH). The fresh tissue group that was not performed cryopreservation was used as the control group. Following the cryopreservation step, MSCs were isolated from all groups and compared with each other to assess the efficiency of the cryopreservation solutions. The comparison was performed in terms of followings: morphology, immunophenotypes, growth kinetics, differentiation, and ultrastructural features. Based on the results, there were no significant morphological and immunophenotypic differences between the MSCs isolated from cryopreserved tissue groups and the MSCs isolated from the fresh tissue group. According to the growth kinetic analysis, the cells isolated from the PrOH group had a lower proliferation rate than the cells isolated from the fresh tissue. However, there was no significant difference between the cryopreserved groups in this respect. Osteogenic and adipogenic differentiation was observed in all groups. Upon comparison of the cryopreserved groups, PrOH group was discovered to hold a minor superiority in terms of these modes of differentiation. These results suggest that PrOH, which is considered as a cryoprotectant with low toxicity, could be used as a preferred cryoprotectant instead of DMSO concerning the process of cryopreservation of the umbilical cord.

The effects of resveratrol on vasospasm after experimental subarachnoidal hemorrhage in rats.

BACKGROUND: Cerebral vasospasm remains a major cause of morbidity and mortality in patients with SAH. Although many pharmacologic agents and chemicals have been used to prevent and treat CV, the pathogenesis of that condition has not been established. We investigated the efficacy of resveratrol, a stilbene polyphenol and tyrosine kinase inhibitor that occurs naturally in grapes and red wine, in a murine basilar artery vasospasm model. METHODS: Forty-two Wistar albino rats were used in this study. The rats were divided into 3 groups of 14 animals each: the sham-operated control group (group 1), the vasospasm group (group 2), and the treatment group (group 3). In groups 2 and 3, autologous blood (0.3 mL) was injected into the cisterna magna. After that injection, the rats in group 3 received an intravenous injection of resveratrol (10 mg/kg) for 72 hours. The evaluation of the response to both the injection of autologous blood and treatment was based on biochemical markers in tissue and serum and on light microscopic findings from the basilar artery, which were collected at different intervals after experimental SAH. RESULTS: Endothelin-1 levels in brain tissue and serum were higher in the vasospasm group than in the control group (P < .05). In group 3 rats, the administration of resveratrol resulted in significantly lower ET-1 values than those in group 2. Brain and serum lipid peroxidation levels were markedly elevated in group 2 rats but decreased significantly after resveratrol treatment in group 3 rats (P < .05). Superoxide dismutase expression in brain tissue and serum was lower in group 2 rats than in sham-operated controls, and a significant increase in the SOD level was associated with resveratrol treatment. On examination via light microscopy 72 hours after SAH, the mean perimeters of the arterial lumen in groups 1, 2, and 3 were 719 +/- 16, 411.6 +/- 9, and 590.1 +/- 5.6 microm, respectively. The mean thickness of the arterial wall was as follows: in group 1, 11.1 +/- 0.8 microm; in group 2, 16.1 +/- 1.2 microm; and (after resveratrol treatment) in group 3, 13.4 +/- 0.6 microm. CONCLUSIONS: The results of our study showed that resveratrol induced the relaxation of smooth muscle in the wall of the basilar artery and may be provided with neuroprotection against cerebral ischemia in a rat model. These effects may be associated with the antioxidant and vasodilatory effects of resveratrol, which could prove to be an agent prophylactic against CV and to be therapeutic for individuals who experience that event.

Complicated granulomatous colitis in a patient with Hermansky-Pudlak syndrome, successfully treated with infliximab.

Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder which is characterised by the triad of oculocutaneous albinism, platelet dysfunction and accumulation of ceroidlike pigment in tissues. Complications of the syndrome, such as fatal pulmonary fibrosis, renal failure and cardiomyopathy have been described. Granulomatous colitis has been documented in several families with the HPS. The bowel disease of the HPS is a unique type of inflammatory bowel disease with clinical features suggestive of idiopathic ulcerative colitis (UC) and pathologic features suggestive of Crohn's disease. We report a patient with HPS which was complicated by granulomatous colitis with perineal and rectovaginal fistulas refractory to antibiotics and azathioprine but dramatically responded to repeated infusions of infliximab.

Dose-dependent neuroprotective effects of melatonin on experimental spinal cord injury in rats.

BACKGROUND: This report examines the dose-dependent effects of melatonin on early lipid peroxidation levels, ultrastructural changes, and neurological function in experimental spinal cord injury (SCI) by comparing them with therapeutic levels of methylprednisone in rats. METHODS: SCI was performed by an aneurysm clip placed extradurally at the level of T10. Rats were randomly divided into six groups of 10 rats each. Group 1 (sham) received only laminectomy; group 2 (control) received SCI; group 3 (placebo) received SCI and physiological saline; group 4 received methylprednisone (30 mg/kg); groups 5 and 6 received melatonin at doses of 50 or 100 mg/kg, respectively, after SCI. Rats were neurologically tested 24 hours after trauma. Spinal cord samples were harvested for both lipid peroxidation levels and ultrastructural histopathological evaluation. RESULTS: Neurological scores of rats were not different in SCI groups. Lipid peroxidation levels are significantly restricted only in methylprednisone group at 24 hours. Melatonin-treated groups showed more ultrastructural improvement on electron microscope studies when compared with methylprednisone group. However, the therapeutic effects of melatonin were mainly observed on white matter of spinal cord in ultrastructural investigation. There was significant difference between melatonin dose groups increasing with dose. CONCLUSIONS: Results showed that melatonin has no significant dose-dependent effects on early lipid peroxidation bur rather some neuroprotective effects on both axons and myelin sheaths of white matter in ultrastructural observations when compared with methylprednisone. These effects significantly augmented with dose increase.

Neuroprotection and functional recovery after application of the caspase-9 inhibitor z-LEHD-fmk in a rat model of traumatic spinal cord injury.

OBJECT: Apoptosis is considered one of the most significant mechanisms in the pathogenesis of neuronal damage after spinal cord injury (SCI). This form of cell death occurs via mediators known as caspases. The aim of this study was to evaluate the neuroprotective effect of the caspase-9 inhibitor, z-LEHD-fmk, in a rat model of spinal cord trauma. METHODS: Fifty-four Wistar albino rats were studied in the following three groups of 18 animals each: sham-operated controls (Group 1); trauma-only controls (Group 2); and trauma combined with z-LEHD-fmk-treated animals (0.8 microM/kg; Group 3). Spinal cord injury was produced at the thoracic level by using the weight-drop technique. Responses to SCI and the efficacy of z-LEHD-fmk treatment were determined on the basis of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling staining and light and electron microscopy findings in cord tissue at 24 hours and 7 days posttrauma. Six rats from each group were also assessed for functional recovery at 3 and 7 days after SCI. This was conducted using the inclined-plane technique and a modified version of the Tarlov motor grading scale. At 24 hours postinjury, light microscopic examination of Group 2 tissue samples showed hemorrhage, edema, necrosis, polymorphonuclear leukocyte infiltration, and vascular thrombi. Those obtained in Group 3 rats at this stage showed similar features. At 24 hours postinjury, the mean apoptotic cell count in Group 2 was significantly higher than that in Group 3 (90.25 +/- 2.6 and 50.5 +/- 1.9, respectively; p < 0.05). At 7 days postinjury, the corresponding mean apoptotic cell counts were 49 +/- 2.1 and 17.7 +/- 2.6, also a significant difference (p < 0.05). Electron microscopy findings confirmed the occurrence of programmed cell death in different cell types in the spinal cord and showed that z-LEHD-fmk treatment protected neurons, glia, myelin, axons, and intracellular organelles. CONCLUSIONS: Examination of the findings in this rat model of SCI revealed that apoptosis occurs not only in neurons and astrocytes but also in oligodendrocytes and microglia. Furthermore, immediate treatment with the caspase-9 inhibitor z-LEHD-fmk blocked apoptosis effectively and was associated with better functional outcome. More in-depth research of the role of programmed cell death in spinal cord trauma and further study of the ways in which caspases are involved in this process may lead to new strategies for treating SCI.

Nicotine improves learning and memory in rats: morphological evidence for acetylcholine involvement.

It has been suggested that nicotine improves rapid information processing (learning and memory) tasks. However, it is not clear which aspects of cognition actually underlie these improvements because relatively less attention has been given to nicotinic cholinergic systems compared to muscarinic systems. The authors therefore studied the effects of nicotine on the learning and memory performance by a step-through passive avoidance task. Nicotine (0.4 mg/kg) was administered s.c. single dose (acute group), once a day for 3 days (subchronic group) or 21 days (chronic group). Nicotine treated and control rats were trained in one trial learning step-through passive avoidance task, where retention latencies were carried out 1 h, 24 h, and 3 days after learning trial. Treatment with nicotine before training session prolonged the latencies significantly (p < .01). Control group, acute, subacute and chronic nicotine treatment groups showed latencies 4.75 +/- 0.6, 69.4 +/- 14, 116.2 +/- 30, and 118.5 +/- 23 s, respectively. In addition, to prove the actual contribution of nicotinic cholinergic system in improvement of learning and memory processing, histological methods that permit the visualization and quantification of ACh levels were used. Electron microscopic evaluation revealed increased numbers of Ach-containing vesicles especially in hippocampus in chronic nicotine-treated rats; although frontal and temporal cortex in addition to hippocampus showed increment in Ach vesicles in a lesser extent in all nicotine treatment groups. These results indicate that long-term nicotine treatment can be important for improving cognitive function in regard to increased cholinergic activity.

Neuroprotective effects of GYKI 52466 on experimental spinal cord injury in rats.

OBJECT: The toxic effects of glutamate in the central nervous system are well known. This neurotoxicity occurs through metabotropic and ionotropic receptors, the latter group composed of N-methyl-D-aspartate, alpha-amino-3-hydroxy-5-methylisoxazole-4-proprionic acid (AMPA), and kainate receptors. The authors investigated the neuroprotective effects of GYKI 52466, a 2,3-benzodiazepine that is a selective and potent AMPA receptor antagonist, in a rat spinal cord trauma model. METHODS: Sixty Wistar albino rats were studied in three groups of 20 animals each: sham-operated controls (Group 1); spinal cord-injured rats (Group 2); and spinal cord-injured plus GYKI 52466-treated rats (Group 3). In Groups 2 and 3, spinal cord injury (SCI) was induced at the thoracic level by applying an aneurysm clip to the cord for 1 minute. One minute after the clip was removed, the rats in Group 3 received an intraperitoneal injection of 15 mg/kg GYKI 52466. Responses to injury and treatment were evaluated based on biochemical parameters (lipid peroxidation and adenosine 5'-triphosphate [ATP] levels in tissue), and on light and transmission electron microscopy findings in cord tissue collected at different times post-SCI. Five rats from each group underwent assessment of functional recovery at 1, 3, and 5 days after SCI; evaluation was performed using the inclined-plane technique and Tarlov motor grading scale. The mean lipid peroxidation levels in Groups 1 and 2 were 21.73 +/- 4.35 and 35.53 +/- 2.99 nmol/g of wet tissue, respectively. The level in Group 3 was 27.98 +/- 3.93 nmol/g of wet tissue, which was significantly lower than that in Group 2 (p < 0.01). The mean ATP levels in Groups 1 and 2 were 166.21 +/- 25.57 and 41.72 +/- 12.28 nmol/g of wet tissue, respectively. The ATP level in Group 3 was 85.82 +/- 13.92 nmol/g of wet tissue, which was significantly higher than that in Group 2 (p < 0.01). Light microscopic examination of Group 2 tissues showed hemorrhage, necrosis, polymorphonuclear leukocyte infiltration, and vascular thrombi. In contrast, the examination of Group 3 tissues showed limited hemorrhage and no necrosis or vascular thrombi. The most prominent findings in Group 2 were hemorrhage and necrosis, whereas the most prominent findings in Group 3 were focal hemorrhage and leukocyte infiltration. Electron microscopy demonstrated that GYKI 52466 protected the neurons, myelin, axons, and intracellular organelles. The mean inclined-plane angles in Groups 1, 2, and 3 were 65 degrees, 40 to 45 degrees, and 55 degrees, respectively. Motor scale results in all groups showed a similar trend. CONCLUSIONS: The findings in this rat model suggest that GYKI 52466 may provide significant therapeutic protection from secondary damage after acute SCI. This agent may be a viable alternative treatment for SCI.