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1.
David Simon Koray Tascilar Sara Unbehend Sara Bayat Andreas Berlin Anna-Maria Liphardt Timo Meinderink Juergen Rech Axel J Hueber Georg Schett Arnd Kleyer 《Journal of bone and mineral research》2020,35(9):1695-1702
The impact of primary hand osteoarthritis (HOA) on bone mass, microstructure, and biomechanics in the affected skeletal regions is largely unknown. HOA patients and healthy controls (HCs) underwent high-resolution peripheral quantitative computed tomography (HR-pQCT). We measured total, trabecular, and cortical volumetric bone mineral densities (vBMDs), microstructural attributes, and performed micro–finite element analysis for bone strength. Failure load and scaled multivariate outcome matrices from distal radius and second metacarpal (MCP2) head measurements were analyzed using multiple linear regression adjusting for age, sex, and functional status and reported as adjusted Z-score differences for total and direct effects. A total of 105 subjects were included (76 HC: 46 women, 30 men; 29 HOA: 23 women, six men). After adjustment, HOA was associated with significant changes in the multivariate outcome matrix from the MCP2 head (p < .001) (explained by an increase in cortical vBMD (Δz = 1.07, p = .02) and reduction in the trabecular vBMD (Δz = −0.07, p = .09). Distal radius analysis did not show an overall effect of HOA; however, there was a gender-study group interaction (p = .044) explained by reduced trabecular vBMD in males (Δz = −1.23, p = .02). HOA was associated with lower failure load (−514 N; 95%CI, −1018 to −9; p = 0.05) apparent in males after adjustment for functional status. HOA is associated with reduced trabecular and increased cortical vBMD in the MCP2 head and a reduction in radial trabecular vBMD and bone strength in males. Further investigations of gender-specific changes of bone architecture in HOA are warranted. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research. 相似文献
2.
Murat Hamit Aytar Fikret Doğulu Berker Cemil Ertan Ergün Gökhan Kurt Kemali Baykaner 《Child's nervous system》2007,23(6):719-721
Introduction Iniencephaly, a neural tube defect involving occiput and inion and combined with rachischisis of the cervical, thoracic spine,
and retroflexion position of the head is a very rare congenital abnormality of the fetus–newborn with a 0.1–10 of 10,000 prevalence.
This abnormality’s prognosis is thought to be dismal. This abnormality can be associated with other abnormalities such as
anencephaly, encephalocele, hydrocephalus, cyclopia, absence of the mandible, cleft lip and palate, cardiovascular disorders,
diaphragmatic hernia, renal abnormalities, overgrowth of the arms compared to the legs, and club food and gastrointestinal
atresia.
Discussion Most of the patients are dead born, and the others die in a few hours. There are only six previously documented long-term
survivors. In our case, our patient with iniencephalic signs and findings is still living. She is 2 years old now. We think
that this patient presents a mild form of iniencephaly. 相似文献
3.
Murat Kuloglu Murad Atmaca Bilal Ustündag Halit Canatan Omer Gecici Ertan Tezcan 《European neuropsychopharmacology》2003,13(2):67-71
The pathophysiology of akathisia still remains controversial. Iron deficiency was proposed to be an important factor in the development of akathisia. In the present study, it was aimed to compare levels of serum iron and linked variables in chronic akathisic (n=30), and non-akathisic patients (n=30) with schizophrenia and healthy controls (n=30) because of the controversy in the association of iron and akathisia. The Barnes Akathisia Scale for akathisia and Simpson-Angus Rating Scale for extrapyramidal side effects were used. Serum iron and linked variables and hematological profile of the patients and control subjects were determined. Serum iron levels were significantly lower both in akathisic and non-akathisic groups compared to the control group (P<0.001). Moreover, akathisic patients had significantly lower iron levels than non-akathisic patients (P<0.05). Total iron binding capacity was significantly higher in patients with akathisia compared to the control group (P<0.01). Although non-akathisic patients had a mild increase in total iron binding capacity, it was not statistically significant compared to the control group (P>0.05). Ferritin levels were determined to be significantly lower in both groups compared to the control group (P<0.01). In addition, there was a significant difference in ferritin levels between the patients with and without akathisia (P<0.05). In conclusion, our results support the hypothesis that an association between akathisia and iron metabolism exists. 相似文献
4.
O Koray Coskunfirat Omer Ozkan 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(12):1336-1341
Reversed flaps from the forearm have been firmly established for hand coverage. Each has its own advantages and disadvantages. The reversed anterior interosseous flap is one option with special advantages in hand reconstruction. From January 2002 to July 2003 we used this flap in five consecutive male patients aged between 36 and 59. The defects were located on the first web space (2), on the dorsal side of the thumb (1), on the first metacarpal bone (1), and on the volar side of the wrist (1). Flap size was between 6 x 3 cm and 11 x 7 cm. All flaps healed without any problem and no complication was observed during the postoperative period. The major advantage of this flap is the preservation of the main arteries of the upper limb. Other advantages are as follows: good texture and colour for hand reconstruction, satisfactory rotation arc, and availability of composite and fascial flaps. Besides its advantages, the major disadvantages are unsightly donor area scar and the need for meticulous technique. As a conclusion, we found this flap very useful in hand reconstruction for coverage of small and moderate sized soft tissue defects of the hand. 相似文献
5.
Omer Ozkan O Koray Co?kunfirat Ozlenen Dogan H Ege Ozgenta? 《Journal of plastic, reconstructive & aesthetic surgery》2007,60(5):556-562
Reverse-flow flaps are currently particularly used for the reconstruction of defects of the distal part of the extremities. Despite their common usage there have been many reports of postoperative complications, especially resulting in partial or total flap necrosis. There is insufficient knowledge of flap haemodynamics, physiology and wound healing properties in reverse-flow flaps. Development of the proper experimental models is needed to investigate these issues. The purpose of this study was to describe a new reverse-flow flap model in the rat. A total of 20 adult Wistar rats weighing 200-250 g were used in this experiment. In five rats, the vascular anatomy of the auricle of the rat was determined by anatomic dissection and microangiography. In the experimental group (N=5), 1x1 cm reverse-flow composite flaps were harvested as a semi-island shape, based on the distal course of the medial branch of the anterior auricular artery. In the control group, consisting of five rats, the flap was designed and raised based on the proximal course of the medial auricular artery, again in a semi-island shape. In the remaining five animals, a square-shaped composite tissue of the whole layer of the auricle, 1x1 cm in size, was harvested dividing all the bases circumferentially. The composite tissue was replaced in situ. While the former was considered a conventional antegrade-flow flap subgroup, the latter was designated as a graft subgroup. All flaps were replaced in situ. The survival of the flap was evaluated on postoperative day 7 by direct observation and microangiography. The skin island of all the reverse-flow flaps and conventional antegrade-flow flaps survived completely giving a success rate of 100%, whereas all grafts in the control group underwent complete necrosis. Microangiographic studies revealed the vascularity of the reverse-flow and antegrade-flow flaps, identifying the course of the auricular arteries. In conclusion, with its evident advantages of easy to design and harvesting, reliable survival pattern and consistent vascular structure, our new flap model will provide a means for future studies on flap haemodynamics, physiology in reverse-flow flaps. 相似文献
6.
A microcapsule form of nitrofurantoin was prepared by a simple coacervation method with carboxymethylcellulose and aluminium sulfate. 33 factorial design was performed for three independent variables, namely, the particle size of the drug, the size of the microcapsules and the pH of the dissolution medium. The dissolution tests with the formulated microcapsules were carried out according to the United States Pharmacopeia XXII rotating basket method at pH 1.2, 5 and 7.5, which represent the pH of gastrointestinal fluids. Release data were examined kinetically and the ideal kinetic models were estimated and t 63.2 values obtained from RRSBW distribution were used in the factorial design experiment. The influence of the independent variables on the dissolution of nitrofurantoin microcapsules could be expressed as the pH of the dissolution medium > particle size of the microcapsule > particle size of nitrofurantoin. The other aim of this study was to evaluate microcapsule formulation in terms of the United States Pharmacopeia criteria with a minimum of experiments. Our findings suggest that dosage forms which comply with the pharmacopoeia criteria for dissolution can be prepared and selected by factorial design. 相似文献
7.
Thomas Meissner Michael Leichsenring Ertan Mayatepek 《Clinical chemistry and laboratory medicine》2004,42(9):1005-1008
Odd-numbered long-chain fatty acids (OLCFAs) increase in total erythrocyte lipids or plasma in patients with propionic acidemia and have been proposed as a useful parameter of metabolic control. However, up to now no parameter for long-term metabolic control has been available for this disorder. In contrast to previous investigations, we investigated OLCFAs with particular reference to differences for two phospholipid fractions of erythrocyte lipids. The phosphatidylethanolamine (PE) fraction of erythrocyte lipids has a slow turnover rate and might reflect the metabolic propionyl-CoA burden over a period of some weeks. Distinct increases in OLCFA of up to 200% in the phosphatidylcholine fraction were observed after episodes of metabolic decompensation and maximum OLCFA levels were found 3 weeks after the onset of a crisis. As a sign of poor metabolic control, OLCFA levels in PE steadily increased after recurrent episodes of decompensation, but not in clinically stable patients. However, in one patient with clinically good metabolic control, OLCFAs continually increased after the second year of life for an as yet unknown reason. In conclusion, data from this study indicate the usefulness of OLCFA analysis in the PE fraction of erythrocyte lipids, in particular with regard to the need for such a parameter for evidence-based improvement of management strategies in propionic acidemia. 相似文献
8.
Progressive motor syndrome in a welder with pallidal T1 hyperintensity on MRI: A two-year follow-up.
Chronic exposure to manganese (Mn) fume during welding may lead to mainly extrapyramidal syndrome that is resistant to treatment. We present a 32-year-old patient who developed severe postural instability, Parkinsonism, dystonia, and pyramidal signs in the 10th year of welding. The neurological condition of the patient worsened markedly in the following 3 years, resulting in severe disability rendering him to be assisted in all his daily activities and he did not benefit from any dopaminergic agent. T1 sequences of the MRI of the brain showed pallidal hyperintensity symmetrically. Welders in our country often protect their eyes but ignore to use tools that protect them from inhalation of the fume. Since chronic Mn toxicity may cause serious disability and irreversible neurological disturbances, we strongly believe that it is necessary to inform welders and their employers about this potential hazard. 相似文献
9.
A mature cystic teratoma in pineal region mimicking parietal encephalocele in a newborn 总被引:1,自引:0,他引:1
M. Kemali Baykaner Ertan Ergun Berker Cemil Pelin Bayik Hakan Emmez 《Child's nervous system》2007,23(5):573-576
Objective Teratoma is the most frequently encountered intracranial tumor at birth and constitutes 18–20% of all germ cell tumors. They
are usually located in pineal and suprasellar regions. The authors aim to report an extremely unusual presentation, location,
and appearance of a teratoma in a newborn.
Case report A soft tissue swelling in the vertex was detected in a 1-month-old girl. Neurological examination was normal. A big, cystic–solid
lesion beginning from pineal region and extending to the scalp was detected in magnetic resonance imaging. It is interesting
to note that cerebral venous angiography showed that the superior sagittal sinus (SSS) was divided into three branches at
the level of the lesion and they joined together distally. The tumor was excised totally. Histopathological examination revealed
the diagnosis of a mature cystic teratoma.
Conclusion A mature cystic teratoma mimicking parietal encephalocele is extremely rare. Germ cell tumors should be kept in mind in the
differential diagnosis of all midline lesions with unusual radiographic appearance. Cerebral venous angiography or MR angiography
must be performed for the diagnosis and the surgical planning in lesions located near SSS. 相似文献
10.
Mahmut Koç Ömer Yoldaş Yusuf Alper Kılıç Erdal Göçmen Tamer Ertan Hayrettin Dizen Mesut Tez 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(5):581-585
Background and aims The aim of this study is to evaluate the predictive accuracy of different scoring systems on surgery for perforated peptic
ulcer referred to an academic department of general surgery in a tertiary reference center.
Patients and methods Seventy-five consecutive patients (Male/female ratio = 64:11; mean age, 44 years; range, 16–85) with perforated peptic ulcer
disease were investigated. Disease severity scores and mortality predictions were calculated using the collected data during
admission. Discrimination and calibration characteristics of each system, namely, the acute physiology and chronic health
evaluation II and III, the simplified acute physiology score II, and the mortality probability models (MPM) II, were determined
by using the area under receiver operating characteristics curve and the Hosmer–Lemeshow goodness-of-fit test, respectively.
Results Among the 75 patients included, there were eight (10.6%) mortalities. All systems had a reliable power of discrimination and
calibration. Among the systems tested, MPM II was the best performing as far as discrimination and calibration characteristics
were considered. The parameters of MPM II system that were related to systemic perfusion of the patient were significantly
positive in patients who died compared to those who survived.
Conclusions MPM II that predicted mortality at admission is better than the other systems in predicting mortality. Results also indicate
the importance of maintenance of systemic perfusion of the patient at the early phases of peptic ulcer perforation. 相似文献