XUV digital in-line holography using high-order harmonics

A step towards a successful implementation of timeresolved digital in-line holography with extreme ultraviolet radiation is presented. Ultrashort XUV pulses are produced as high-order harmonics of a femtosecond laser and a Schwarzschild objective is used to focus harmonic radiation at 38 nm and to produce a strongly divergent reference beam for holographic recording. Experimental holograms of thin wires are recorded and the objects reconstructed. Descriptions of the simulation and reconstruction theory and algorithms are also given. Spatial resolution of few hundreds of nm is potentially achievable, and micrometer resolution range is demonstrated.Comment: 8 pages, 8 figure

Pancreatic Perivascular Epithelial Cell Tumor (PEComa) with Liver Metastasis: a Case Report and Literature Review

Aim: to present a clinical case of pancreatic PEComa with liver metastases with an emphasis on morphological features, radiology diagnostic methods and features of treatment tactics, allowing practitioners to get an idea about this rare mesenchymal tumors composed of “perivascular epithelioid cells”, and a review of literature data on pancreatic PEComa, including 32 author's cases.General statements. A 22-year-old woman who was surgically treated for pancreatic head PEComa with infiltration of the duct of Wirsung, common bile duct, duodenal wall, focal invasion into the blood and lymphatic vessels, and perineural space infiltration. Synchronously, metastases were detected in both liver lobes, for which she took Everolimus for 6 years under the control of radiology methods with dose adjustment and frequency of administration. At the A.V. Vishnevsky National Medical Research Center of Surgery, the patient underwent right-sided hemihepatectomy and atypical resection of II-III liver segments.Conclusion. To determine clearer criteria for the diagnosis and differential diagnosis of PEComa, to identify criteria for the malignancy of these tumors, to develop treatment tactics and further dynamic monitoring, a set of statistical data of significant group and randomized clinical trials are needed. Pancreatic PEComas in this group are extremely rare and often have a benign course. The presented clinical case demonstrates the most malignant form of this tumor with localization in the pancreas and liver metastases

Diagnostic and Treatment Errors in Biliary Cystadenomas and Cystadenocarcinomas: Clinical Cases

Background. Biliary cystadenomas and cystadenocarcinomas are rare cystic tumors of the liver. Complicated differential diagnostics for simple cysts often leads to errors in surveillance of patients with these tumors. Cystadenoma and cystadenocarcinoma should be suspected upon detection of single or multilocular cystic neoplasms of the liver with septa and blood flow loci  in the cyst wall, especially in middle-aged women. The localization of the tumor is critical. The most common localization is segment IV of the liver. Urgent intraoperative biopsy is required to determine the extent of surgery.Case description. Clinical observations with analysis of the examination and treatment data of two female patients aged 38 and 56 were presented. Both clinical observations illustrate the underestimation of the preoperative examination data that served as a ground for diagnosis of liver cysts with inadequate extent of surgery. In the first case, the resection was incomplete, and, as such, the biliary cystadenoma recurred in the resection area, the capsule of the neoplasm was ruptured and an encysted fluid collection was formed. In the second case, lack of histological examination of the excised neoplasm, due to confidence in its morphological verification as a cyst, resulted in cystadenoma recurrence in the resection zone with metastasis to the contralateral lobe of the liver.Conclusion. Hepatic cystadenomas and cystadenocarcinomas are often misdiagnosed as simple cysts. These tumors should be suspected in central localization of the tumor in the liver, especially in young women. The clinical and instrumental symptomatology and radiological semiotics of the disease require careful evaluation. The recurrence of a cystic lesion in the resection zone in a patient previously operated for a hepatic cyst serves as an additional signal for detecting biliary cystadenoma. Rational strategy for surgical management of cystic liver lesions should include hepatectomy within healthy tissues (both anatomical and atypical) with mandatory intraoperative ultrasound and urgent histological examinations

First Observation of Self-Amplified Spontaneous Emission in a Free-Electron Laser at 109 nm Wavelength

We present the first observation of Self-Amplified Spontaneous Emission (SASE) in a free-electron laser (FEL) in the Vacuum Ultraviolet regime at 109 nm wavelength (11 eV). The observed free-electron laser gain (approx. 3000) and the radiation characteristics, such as dependency on bunch charge, angular distribution, spectral width and intensity fluctuations all corroborate the existing models for SASE FELs.Comment: 6 pages including 6 figures; e-mail: [email protected]

COMORBIDITY IN HEMICONVULSION-HEMIPLEGIA-EPILEPSY SYNDROME IN CHILDREN

Hemiconvulsion-hemiplegia-epilepsy (HHE) syndrome is a rare consequence of focal status epilepticus (SE) in childhood. The major discerning feature of the syndrome is the unilateral brain lesion during SE with subsequent development of hemiparesis and drug-resistant epilepsy. The unilateral brain damage in SE is not fully understood. We hypothesized that comorbidity could be the cause of this the hemisphere damage; to that end, we searched for the evidence of comorbidity in patients with HHE.Objective: to analyze the concomitant pathology in patients with HHE, which was the possible cause of unilateral brain damage.Materials and methods. Four patients with HHE syndrome (aged from 1 year 2 months to 6 years; three boys and a girl) were examined.Results. The course of the disease in all patients met the criteria of HHE; various manifestations of comorbidity were found in all four patients. Thus, patient A.A. (6 years old) had hypothyroidism, the history of consciousness loss, acetone smell from the mouth, and spontaneous generalized seizure attacks starting from the age of 11 months. Patient V.S. (6 years old) had adrenogenital syndrome and inborn glaucoma. Patient D.Sh. (1 year 10 months old) had a structural heart defect, a high degree of stigmatization, and suspected Wolf-Hirschhorn syndrome. Patient V.Kh. (3 years old) had cerebral palsy and post-hemorrhagic occlusion hydrocephaly.Conclusion. We propose that comorbidity can be the cause of hidden or obvious lesions in one hemisphere, which can explain the unilateral brain damage in HEE syndrome

FOCAL CORTICAL DYSPLASIA: ALGORITHM OF PREOPERATIVE EXAMINATION

In this paper we are discussing the issues of diagnosis, classification, features of preoperative evaluation and surgical treatment of focal cortical dysplasia in children. Particular attention is paid to the complexities of visualization of FCD, as well as the reasons of frequent poor postoperative outcomes in epilepsy associated with FCD

MODERN TREATMENT OF DRUG-RESISTANT EPILEPSY, AVAILABLE IN RUSSIAN

Treatment of drug-resistant epilepsy is an extremely difficult task. Unfortunately, in Russia there are no regulations containing the algorithm of actions to help the practical neurologist in management of drug-resistant patients. It is obvious that there is an urgent need to establish a network of specialized epilepsy centers of level 4 (classification of the National Association of Epilepsy Centers, USA) in the territory of the Russian Federation, united by a common ideology and methodology.Objective: to increase the quality of care for patients with refractory forms of epilepsy, by combined use of non-drug treatments such as surgery, ketogenic diet and chronic vagus nerve stimulation (VNS Therapy).Material and methods. We observed 168 patients aged 1 to 18 years with refractory epilepsy.Results. Surgical treatment was performed in 63 patients, ketogenic diet — 73, VNS therapy — 32 patients. Analysis of the combined effectiveness showed the following results: complete seizure control was observed in 59 (35.1%) patients; reducing the number of seizures of more than 75% — in 19 (11.3%), 50% — and 53 (31.5%), no effect, — 37 (22%). Thus, the significant improvement was observed on the whole in 131 (78%) patients of 168. Conclusions. An integrated approach, involving a differentiated choice of a non-drug treatment allows to achieve significant positive results, despite the resistance of epilepsy to drug therapy

SEVERE EPILEPTIC ENCEPHALOPATHY OF EARLY CHILDHOOD DUE TO SCN2A MUTATION

SCN2A mutations are traditionally described in benign infantile seizures. We are describing rather rare case of epileptic encephalopathy associated with incertion of ctg/ctGg in SCN2A. The female child was born at term by normal delivery after non-complicated pregnancy. Seizures started when she was 3 months old as focal tonic, later on myoclonic seizures developed. They were refractory to all used antiepileptic drugs including valproic acid, topiramate, lamotrigine, ethosuximide and tetracoside. At age of two child is mentally retarded and autistic, unable to walk (because of muscular hypotonia), has no active speech and still has asymmetrical tonic and myoclonic seizures. Unspecific modest brain atrophy was revealed by MRI. Metabolic screening, including urine and serum amino acids, organic acids, lactate, was normal. Our case (alongside with others depicted in literature) confirms that spectrum of phenotypes, associated with mutations in SCN2A, is very wide – from benign infantile seizures to severe epileptic encephalopaties leading to mental retardation, motor and speech disorders