Publications by authors named "Elek G"

Ervin Bauer (1890-1938) made historical contributions to contemporary biology, provided a new definition of life, defined the contents of theoretical biology. He worked in different countries, perturbed by deep historical events. These historical events necessarily impacted his fate and finally led to the violent loss of his life and the life of his wife.

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The development of biological concepts in the 19th century was followed by the emergence of approaches to formulate the principles of theoretical biology. Ervin Bauer in 1920, and in more detail in 1935, suggested the basic principle that can be accepted as the fundamental law of biology: "The living systems are never in equilibrium; at the expense of their free energy they constantly perform work to avoid the equilibrium required by the laws of physics and chemistry under existing external conditions." Many researchers interpreted biology with the help of physical quantities but Bauer was the first to build a general and already molecular-based biological theory.

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(Borylmethyl)trimethylsilanes are important building blocks in organic synthesis displaying a unique reactivity. Yet, the synthesis of more advanced derivatives is limited by the advanced silicon intermediates required for their preparation. Herein, a one-pot synthesis of (borylmethyl)silanes is developed, sourced on available alkyl-, aryl-, alkoxy-, aryloxy-, and silyl-hydrosilane materials.

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Despite the remarkable advances in the area of asymmetric catalytic oxidations over the past decades, the development of sustainable and environmentally benign enantioselective oxidation techniques, especially with the efficiency level similar to natural enzymes, still represents a challenge. The growing demand for enantiopure compounds and high interest to industry-relevant green technological advances continue to encourage the research pursuits in this field. Among various oxidants, molecular oxygen is ubiquitous, being available at low cost, environmentally benign and easy-to-handle material.

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Oxidative fragmentation of tertiary cyclopropanols with phenyliodine(III) dicarboxylates in aprotic solvents (dichloromethane, chloroform, toluene) produces mixed anhydrides. The fragmentation reaction is especially facile with phenyliodine(III) reagents bearing electron-withdrawing carboxylate ligands (trifluoroacetyl, 2,4,6-trichlorobenzoyl, 3-nitrobenzoyl), and affords 95-98% yields of the corresponding mixed anhydride products. The latter can be straightforwardly applied for the acylation of various nitrogen, oxygen and sulfur-centered nucleophiles (primary and secondary amines, hydroxylamines, primary alcohols, phenols, thiols).

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A unified step-economical strategy for accessing histone deacetylase inhibitory peptides is proposed, based on the late-stage installation of multiple zinc-binding functionalities via the cleavage of the strained cyclopropane ring in the common pluripotent cyclopropanol precursor. The efficacy of the proposed diversity-oriented approach has been validated by short stereoselective synthesis of natural product chlamydocin, containing a challenging-to-install fragment of (2,9)-2-amino-8-oxo-9,10-epoxydecanoic acid (Aoe) and a range of its analogues, derivatives of 2-amino-8-oxodecanoic and 2-aminosuberic acids.

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Tertiary cyclopropanols undergo ring-opening oxidative sulfonylation to afford γ-keto sulfones when reacting with sulfinate salts in the presence of a copper(ii) acetate catalyst and an oxidant (tert-butyl hydroperoxide or atmospheric oxygen). Various fluoroalkyl, aryl and alkyl sulfinate salts are successfully employed as sulfonylation reagents, affording the corresponding sulfones in up to 94% yields. The experimental protocol is mild and tolerates a number of functionalities in the cyclopropanol substrate.

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An efficient, mild, and environmentally benign method was developed for the asymmetric synthesis of 2-oxyranyl ketones from easily available tertiary cyclopropanols. The one-pot protocol includes the aerobic oxidation of cyclopropanol derivatives catalyzed by Mn(III) complexes followed by the poly-l-leucine-assisted stereoselective elimination of water from the intermediate peroxides with DBU to afford the corresponding epoxy ketones in high yields and good-to-excellent enantioselectivities (up to 97%).

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Ervin Bauer is one of the first theoretical biologists distancing his ideas both from vitalism and mechanicism. He formulated the principle of permanent non-equilibrium of living systems (Bauer's principle) in terms of thermodynamics in 1920. Bauer's scientific path can be divided into three periods.

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Although stomach is a frequent site of extranodal lymphomas, histiocyte-rich TCRBCL has not yet been described there. Even histology of repeated gastrobiopsies of this uncommon, diffuse, large B-cell lymphoma may be inconclusive and partial gastrectomy cannot be avoided. It is only immunohistology (CD20, CD43, CD68) of the paraffin blocks from the resection specimen that can lead to the final diagnosis of intermediate grade malignant lymphoma.

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Proteins in tissues and biofluids and their many attributes define the proteome. Proteome can be directly correlated to known diseases and histological regions allowing the diagnosis and monitoring of disease progression as well predicting the patient's response to specific treatments. Proteomics performs large-scale, high-throughput characterization of the human proteome, among others by biological mass spectrometry.

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Two hundred and five preoperative intraductal samplings (brushing and biopsy) were evaluated from 113 patients with biliary or Wirsung duct strictures. One hundred and three strictures could be specified by histology of the operative specimens, autopsy, or by the patients' clinical course. Preoperative diagnostic efficacy depended on the tumor location (it was the best for ampullary and para-papillary tumors), but the average quantitative indices for sensitivity, absolute sensitivity, specificity, positive and negative predictive values, diagnostic accuracy of cytology were 53%, 20%, 100%, 100%, 25%, 59%, respectively.

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A big gallstone penetrating through a bilio-digestive fistula into the bowel can make a complete obstruction of it in the majority of the cases requiring an urgent operation. It is a rare situation that a fistula like this leads into the colon and the stone makes a large bowel obstruction. A 72-year-old male patient was admitted to our department with the symptoms of colon obstruction.

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Frequency of the lesions of the papilla Vateri is increasing in Hungary because of epidemiological reasons. Over two years nearly 300 ampullary endoscopic biopsies were taken in our hospital. In 36 percent of the patients the papillary specimens demonstrated acute or chronic inflammation, in 44 percent adenoma, including 5 percent with severe dysplasia, in 5 percent adenomatous hyperplasia and in 7 percent adenomyosis or other benign tumors (2%) were found.

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Introduction: Sphincter of Oddi dysfunction is a real challenge from both diagnostic and therapeutic point of view.

Patients And Methods: In the last two years the authors have performed ERCP and EST in 29 patients with positive evocative test results, who had important enzyme elevations and/or did not respond to prolonged medical treatment.

Results: Endoscopic findings were positive in 25/29 patients (86.

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Aim: To determine whether assays of carcinoembryonic antigen (CEA) and cholesterol in ascites add diagnostic value to cytology.

Methods: The additional diagnostic efficacy of the biochemical assays was studied in the ascitic fluid from 130 patients, of whom 57 had peritoneal carcinomatosis. All diagnoses were verified by subsequent necropsy and/or histology.

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About ten cases of filariosis have recently been recorded in the Hungarian medical literature, six of them caused by Dirofilaria repens. Dirofilaria repensis a mosquito-transmitted filaroid worm in the subcutaneous tissue of dogs and cats in the temperate areas of the Old World. It accidentally infects man, too, and can remain unidentified due to physicians, poor knowledge of the parasite.

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Central neurocytoma is a benign neuronal tumor of young adults in the lateral cerebral ventricles with characteristic X ray and light microscopic findings. In many respects typical central neurocytoma is reported below, with recurrence in the third month requiring reoperation. Death ensued in the fifth postoperative month.

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Orchiectomy was performed in a 37-year-old Hungarian man exhibiting a swelling in his right testicle. Histology revealed a nodule attached to the spermatic cord, consisting of a granulomatous tissue around sections of a nematode. The worm was identified as Dirofilaria repens, an uncommon parasite in Hungary.

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We propose and investigate new types of neural network models. They can be viewed as discrete linear systems operating on closed and bounded, that is, compact, convex domains. We first analyze the dynamic behavior of a neural network model on an arbitrary convex domain.

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Methods of microwave and vacuum-accelerated fixation, dehydration, and paraffin embedding are described, using a new type of vacuum and temperature stabilizable microwave histoprocessor: MFX-800. The whole histoprocessing cycle lasts 3.5-5.

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Methods of microwave and vacuum accelerated fixation, dehydration and paraffin embedding are described. They can be carried out in a new type of vacuum and temperature stabilizable microwave histoprocessor: MFX-800. The whole histoprocessing lasts 3.

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Conventional cytological evaluation of serous effusions often yields border line result: apart from positive (malignant) or negative (benign) diagnoses, a relatively large part of the findings are "suspicious for malignancy" (P3). In the present paper the authors have analysed to what extent contributes the determination of cholesterol and CEA levels of ascites and pleural effusion to the diagnostic accuracy of cytologically "suspicious" (P3) cases. In 155 histologically controlled cases, specificity, sensitivity and diagnostic efficiency were assessed on the basis of cytology as well as the determination of CEA and cholesterol levels.

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