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One of the most common craniofacial malformations observed in newborn babies is cleft lip and palate (CLP). This syndrome presents with some anatomic variations. The aim of this study was to understand an anatomic variation of the crista galli that had not been reported previously in patients with CLP. A 17-year-old boy with CLP was referred to an orthodontic clinic for cone-beam computed tomography (CBCT) imaging before treatment. Axial and coronal sections and three-dimensional images showed that the crista galli had bifid heads that were attached to each other. Incomplete ossification had resulted in a bifid crista galli and the appearance of a suture in the anterior coronal section of the CBCT images. This anatomic variation could allow penetration of the anterior fossa during endoscopic surgery, which could be dangerous for the patient.  相似文献   
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Malignant brain tumors are characterized by destructive growth and neuronal cell death making them one of the most devastating diseases. Neurodegenerative actions of malignant gliomas resemble mechanisms also found in many neurodegenerative diseases such as Alzheimer''s and Parkinson''s diseases and amyotrophic lateral sclerosis. Recent data demonstrate that gliomas seize neuronal glutamate signaling for their own growth advantage. Excessive glutamate release via the glutamate/cystine antiporter xCT (system xc-, SLC7a11) renders cancer cells resistant to chemotherapeutics and create the tumor microenvironment toxic for neurons. In particular the glutamate/cystine antiporter xCT takes center stage in neurodegenerative processes and sets this transporter a potential prime target for cancer therapy. Noteworthy is the finding, that reactive oxygen species (ROS) activate transient receptor potential (TRP) channels and thereby TRP channels can potentiate glutamate release. Yet another important biological feature of the xCT/glutamate system is its modulatory effect on the tumor microenvironment with impact on host cells and the cancer stem cell niche. The EMA and FDA-approved drug sulfasalazine (SAS) presents a lead compound for xCT inhibition, although so far clinical trials on glioblastomas with SAS were ambiguous. Here, we critically analyze the mechanisms of action of xCT antiporter on malignant gliomas and in the tumor microenvironment. Deciphering the impact of xCT and glutamate and its relation to TRP channels in brain tumors pave the way for developing important cancer microenvironmental modulators and drugable lead targets.  相似文献   
4.
BackgroundPulmonary hypertension (PHT) and right ventricular (RV) dysfunction are among the commonly observed and potentially serious complications following heart transplantation. RV dysfunction is reported to occur in as much as half of these patients. In this study, the authors sought to examine the prevalence and the course of these prognostically important complications.MethodsThe records of 30 patients who had undergone orthotopic heart transplantation at our center were examined. Demographic and clinical variables were noted; RV dysfunction, pulmonary artery pressure on Doppler echocardiographic examination, and catheter findings were recorded.ResultsThe mean age of the study population was 31.3 years. On preoperative assessment, PHT was present in 21 (70%) patients. The average value of systolic pulmonary artery pressure was 44.5 ± 5.9 mm Hg. The mean value of pulmonary vascular resistance was 3.3 ± 1.8 hybrid reference unit (HRU). RV dysfunction was detected on postoperative assessment in 17 (56.7%) patients. The mean ischemia time was 216 ± 77 minutes; in 3 cases it exceeded 5 hours but in none of the cases did it reach 6 hours. Rejection was detected in 14 (46.7%) patients. Most of the patients received inotropic agents in the early postoperative period. When compared with preoperative values, on follow up at the end of the first year, a significant decrease in pulmonary artery pressure was observed (47.4 ± 4.8 vs 38.5 ± 7.5 mm Hg; P = .03), and the ratio of patients experiencing RV dysfunction decreased to 16.6% (n = 5).ConclusionThe findings of this study indicate that RV dysfunction and PHT are common complications following heart transplantation and improve with appropriate management over time with monitoring.  相似文献   
5.
A distinguishability measure is defined for magnetic resonance-electrical impedance tomography (MR-EIT) based on magnetic flux density measurements. This general definition is valid for 2D and 3D structures of any shape. As a specific case, a 2D cylindrical body with concentric inhomogeneity is considered and a bound of the distinguishability is analytically formulated. Distinguishabilities obtained with potential and magnetic flux density measurements are compared.  相似文献   
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Since 1939, it has been known that, silicosis and extrinsic allergic alveolitis can be seen among dental technicians. The interstitial disease caused by the exposure to complex substances used by dental technicians is classified as a special group called dental technician's pneumoconiosis. A 36-year-old man, who has no smoking history, presented with severe dyspnea. He had worked in different dental laboratories for 22 years, but he did not have respiratory symptoms until five years ago. After that date, he had hospitalized and had been examined for respiratory pathologies for many times. He had came to our clinic, because of the progression of his dyspnea. Diffuse pulmonary parenchymal infiltrates which can be related with pneumoconiosis and chronic type 1 respiratory deficiency had been diagnosed as the result of the examinations. While he has no history of smoking or any other risk factors or diseases in his medical history, the case was accepted as dental technician's pneumoconiosis. The factors related with the pathogenesis of dental technician's pneumoconiosis are; the complex compound of the substances (metal dusts, silica, plaster, wax and resins, chemical liquids, methyl methacrylate) used in this sector and their effects on the lung parenchyma. Extrinsic allergic alveolitis related with methyl methacrylate has been reported. The most important factor to acquire an occupational lung disease is a complex occupational exposure. The insufficient workplace airing and the lack of preventive measures added on this exposure, the risks become much more greater.  相似文献   
8.

Background

Infections are an important acquired cause of cerebral arteriopathy. Tuberculous (TB) meningitis leading to infectious cerebral vasculopathy is a rare cause of acute hemiparesis.

Case report

A 14-year-old male patient was examined after acute hemiparesis developing within 1 day. Neurological examination revealed total hemiplegia on the left side. Brain MRI findings showed bilateral focal T2-weighted signal hyperintensity in the subcortical and deep white matter regions. There were also areas of restricted diffusion in the right basal ganglia. Although the father had a history of pulmonary TB, the patient had not been given TB prophylaxis because of PPD negativity. At lumbar puncture, opening cerebrospinal fluid (CSF) pressure was 50 cm/H20, CSF protein 66.9 mg/dL, and glucose 54 mg/dL (concurrent blood glucose 93 mg/dL); 170 polymorphonuclear leukocytes per cubic millimeter were present in CSF. Following tests for TB, treatment was started immediately with four anti-TB drugs. TB PCR of CSF and acid-fast bacteria (AFB) staining in gastric aspirate were positive. At clinical follow-up, the patient was able to walk with support at the end of the first month.

Conclusion

Various infectious agents have been reported as causes of cerebral vasculopathy. TB, which affects a significant number of patients worldwide, should be kept in mind in terms of cerebral vascular complications. Lumbar puncture is essential in order to diagnose TB meningitis.  相似文献   
9.
OBJECTIVES: Congenital anomalies and intrauterine fetal death (IUFD) are frequent problems in pregnancies. Detection of the etiology is important for genetic counseling, and presenting the geographic distribution of the causes of disorders is necessary for a national policy on precautions. Here, we report the findings of terminated fetuses due to IUFD and congenital anomalies in Turkish population. METHODS: Physical examinations of fetuses and genetic evaluations of families were done. X-ray studies and autopsy were done in the event of necessity. Findings of these studies were combined with prenatal ultrasound results. All cases were classified according to ICD-10. RESULTS: The number of fetuses examined was 2407. Out of these, 1268 fetuses had congenital anomalies. Neurologic anomalies and musculoskeletal system malformations were the most frequent disorders. Specific diagnoses were possible in 64% of all multiple malformation syndromes.Abnormal findings were detected in 18.8% of IUFD fetuses. Nine percent had congenital anomalies and 5.2% had cord complications. The percentage of twins and triplets was 7.5% and 13% of them had anomalies. CONCLUSION: Postmortem evaluation is useful to detect findings necessary for genetic counseling. Our protocol is effective especially in fetuses with congenital anomalies but it can detect only some of the fetal reasons in IUFD cases. A more detailed protocol is needed to investigate IUFD cases.  相似文献   
10.
The distinguishability of a discrete coil induced current electrical impedance tomography system is analysed. The solution methodology of the forward problem of this system is explained. An optimization procedure using this forward problem solution is developed to find optimum currents that maximize the distinguishability. For the concentric inhomogeneity problem, it is shown that the coil currents can be optimized to focus the current density in any desired location, in the field of view. Optimum coil currents under the constraints of limited peak coil currents and limited total power are determined. Examples that demonstrate the performance of the system are presented.  相似文献   
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