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1.
Nature ; 585(7823): 58-62, 2020 09.
Article in English | MEDLINE | ID: mdl-32879499

ABSTRACT

Scanning probe techniques can leverage atomically precise forces to sculpt matter at surfaces, atom by atom. These forces have been applied quasi-statically to create surface structures1-7 and influence chemical processes8,9, but exploiting local dynamics10-14 to realize coherent control on the atomic scale remains an intriguing prospect. Chemical reactions15-17, conformational changes18,19 and desorption20 have been followed on ultrafast timescales, but directly exerting femtosecond forces on individual atoms to selectively induce molecular motion has yet to be realized. Here we show that the near field of a terahertz wave confined to an atomically sharp tip provides femtosecond atomic-scale forces that selectively induce coherent hindered rotation in the molecular frame of a bistable magnesium phthalocyanine molecule. Combining lightwave-driven scanning tunnelling microscopy21-24 with ultrafast action spectroscopy10,13, we find that the induced rotation modulates the probability of the molecule switching between its two stable adsorption geometries by up to 39 per cent. Mapping the response of the molecule in space and time confirms that the force acts on the atomic scale and within less than an optical cycle (that is, faster than an oscillation period of the carrier wave of light). We anticipate that our strategy might ultimately enable the coherent manipulation of individual atoms within single molecules or solids so that chemical reactions and ultrafast phase transitions can be manipulated on their intrinsic spatio-temporal scales.

2.
Nat Nanotechnol ; 12(3): 207-211, 2017 03.
Article in English | MEDLINE | ID: mdl-27941900

ABSTRACT

The possibility of hybridizing collective electronic motion with mid-infrared light to form surface polaritons has made van der Waals layered materials a versatile platform for extreme light confinement and tailored nanophotonics. Graphene and its heterostructures have attracted particular attention because the absence of an energy gap allows plasmon polaritons to be tuned continuously. Here, we introduce black phosphorus as a promising new material in surface polaritonics that features key advantages for ultrafast switching. Unlike graphene, black phosphorus is a van der Waals bonded semiconductor, which enables high-contrast interband excitation of electron-hole pairs by ultrashort near-infrared pulses. Here, we design a SiO2/black phosphorus/SiO2 heterostructure in which the surface phonon modes of the SiO2 layers hybridize with surface plasmon modes in black phosphorus that can be activated by photo-induced interband excitation. Within the Reststrahlen band of SiO2, the hybrid interface polariton assumes surface-phonon-like properties, with a well-defined frequency and momentum and excellent coherence. During the lifetime of the photogenerated electron-hole plasma, coherent hybrid polariton waves can be launched by a broadband mid-infrared pulse coupled to the tip of a scattering-type scanning near-field optical microscopy set-up. The scattered radiation allows us to trace the new hybrid mode in time, energy and space. We find that the surface mode can be activated within ∼50 fs and disappears within 5 ps, as the electron-hole pairs in black phosphorus recombine. The excellent switching contrast and switching speed, the coherence properties and the constant wavelength of this transient mode make it a promising candidate for ultrafast nanophotonic devices.

3.
Neuromuscul Disord ; 22(7): 604-16, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22520280

ABSTRACT

The pathogenesis of myotonic dystrophy type 2 includes the sequestration of MBNL proteins by expanded CCUG transcripts, which leads to an abnormal splicing of their target pre-mRNAs. We have found CCUG(exp) RNA transcripts of the ZNF9 gene associated with the formation of ribonuclear foci in human skeletal muscle and some non-muscle tissues present in muscle biopsies and skin excisions from myotonic dystrophy type 2 patients. Using RNA-FISH and immunofluorescence-FISH methods in combination with a high-resolution confocal microscopy, we demonstrate a different frequency of nuclei containing the CCUG(exp) foci, a different expression pattern of MBNL1 protein and a different sequestration of MBNL1 by CCUG(exp) repeats in skeletal muscle, vascular smooth muscle and endothelia, Schwann cells, adipocytes, and ectodermal derivatives. The level of CCUG(exp) transcription in epidermal and hair sheath cells is lower compared with that in other tissues examined. We suppose that non-muscle tissues of myotonic dystrophy type 2 patients might be affected by a similar molecular mechanism as the skeletal muscle, as suggested by our observation of an aberrant insulin receptor splicing in myotonic dystrophy type 2 adipocytes.


Subject(s)
Muscle, Skeletal/metabolism , Myotonic Disorders , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , Actins/metabolism , Adipocytes/metabolism , Adipocytes/pathology , Analysis of Variance , Antigens, CD34/metabolism , Endothelium/metabolism , Endothelium/pathology , Humans , Microscopy, Confocal , Myotonic Disorders/diagnosis , Myotonic Disorders/genetics , Myotonic Disorders/metabolism , Myotonic Disorders/pathology , Myotonic Dystrophy , Neurofilament Proteins/metabolism , Protein Transport/physiology , RNA/metabolism , RNA Splicing/genetics , Receptor, Insulin/genetics , Repetitive Sequences, Nucleic Acid/genetics , S100 Proteins/metabolism , Skin/metabolism , Skin/pathology
4.
Vnitr Lek ; 56(8): 824-6, 2010 Aug.
Article in Czech | MEDLINE | ID: mdl-20845614

ABSTRACT

Autoimmune LgG4- associated cholangitis is a new entity among the liver and biliary tree disorders, classified among the so-called IgG4-related diseases. Even though prognosis of this disease is unclear, this type of sclerosing cholangitis is not being linked to a carcinoma. Clinical and laboratory data differ slightly from the findings associated with the usual primary sclerosing cholangitis and it is mainly the high IgG4 level and hyperbilirubinaemia that supports the diagnosis ofautoimmune disease. Unlike primary sclerosing cholangitis, this disease is not associated with a malignant prognosis and steroids represent an effective treatment. Combination of steroids with azathioprin is a possible alternative in case of a relapse. Patient's response to steroid therapy is a diagnosis-supporting criterion. This disease should always be considered as part of differential diagnosis of primary sclerosing cholangitis, especially when autoimmune aberrations or other autoimmune diseases are present. Long-term evaluations of these patients are so far lacking and thus studies on larger patient samples are required.


Subject(s)
Autoimmune Diseases/diagnosis , Cholangitis, Sclerosing/diagnosis , Immunoglobulin G/blood , Diagnosis, Differential , Humans , Male , Young Adult
5.
Genet Test ; 10(2): 85-97, 2006.
Article in English | MEDLINE | ID: mdl-16792511

ABSTRACT

Human neurodegenerative and neuromuscular disorders are associated with a class of gene mutations represented by expansion of trinucleotide repeats. DNA testing is important for the diagnosis of these diseases because clinical discrimination is complicated by their late onset and frequently overlapping symptomatology. However, detection of pathologic alleles expanded up to several thousand trinucleotides poses a challenge for the introduction of rapid, fully automatic, and simple DNA diagnostic procedures. Here we propose a simple two-step polymerase chain reaction (PCR) protocol for rapid molecular diagnostics of myotonic dystrophy, Huntington's disease, and possibly also other triplet expansion diseases. Standard PCR amplification with target repeat flanking primers is used for the detection of alleles of up to 100 repeats; next, triplet-primed PCR is applied for detection of larger expansions. Automated capillary electrophoresis of amplicons allows rapid discrimination between normal, premutated and expanded (CTG/CAG)(n) alleles. Using the suggested protocol, the expanded allele was successfully detected in all test DNA samples with known genotypes. Our experience demonstrates that the suggested two-step PCR protocol provides high sensitivity, specificity, and reproducibility; is significantly less time-consuming; is easier to perform; and provides a better basis for automation than previous methods requiring Southern analysis. Therefore, it can be used for confirmation of uncertain clinical diagnoses, for prenatal testing in at-risk families, and, generally in research on these diseases.


Subject(s)
Huntington Disease/genetics , Molecular Diagnostic Techniques/methods , Myotonic Dystrophy/genetics , Polymerase Chain Reaction/methods , Trinucleotide Repeat Expansion , Alleles , Electronic Data Processing , Genetic Carrier Screening/methods , Genomic Instability , Humans , Huntingtin Protein , Molecular Probe Techniques , Nerve Tissue Proteins/genetics , Nuclear Proteins/genetics
6.
Eur J Neurol ; 11(8): 531-4, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15272897

ABSTRACT

The X-linked Emery-Dreifuss muscular dystrophy (X-EDMD) is a hereditary muscle disorder associated with cardiac involvement. Sinus node dysfunction and atrioventricular conduction defects, typical of X-EDMD, occur in both males and females and may result in sudden cardiac death unless treated by permanent pacing. The objective of the study was to determine the frequency and relevance of X-EDMD in heart conduction system disease in young individuals treated with a pacemaker implant. The medical history of 3450 paced individuals in the region of South Moravia, Czech republic, was reviewed. Thirty-five patients, 20 males and 15 females, with idiopathic heart conduction disease of onset before age 40 were identified and screened for X-EDMD. Within these 35 individuals, only one male was found to carry a mutation in X-EDMD gene. We conclude that the clinical relevance of X-EDMD in heart conduction system disease is very low. It should, however, be included into the diagnostic work-up of young male individuals with idiopathic cardiac conduction disturbances.


Subject(s)
Arrhythmias, Cardiac/physiopathology , Heart Conduction System/physiopathology , Muscular Dystrophy, Emery-Dreifuss/etiology , Pacemaker, Artificial , Adolescent , Adult , Databases as Topic/statistics & numerical data , Female , Humans , Immunohistochemistry/methods , Male , Membrane Proteins/metabolism , Middle Aged , Mouth Mucosa/metabolism , Muscle, Skeletal/metabolism , Nuclear Proteins , Thymopoietins/metabolism
7.
Cesk Patol ; 40(2): 57-62, 2004 Apr.
Article in Czech | MEDLINE | ID: mdl-15233018

ABSTRACT

The congenital muscular dystrophies (CMD, MDC) represent a heterogeneous group of autosomal recessive disorders manifesting in infancy by muscle weakness and hypotonia. Approximately 40% of patients with CMD have a primary deficiency of the laminin alpha 3. chain of merosin (laminin-2) due to mutations in LAMA2 gene. Laminin-2 bound to alpha-dystroglycan forms a link between actin--associated cytoskeletal proteins and the components of extracellular matrix. Disruption of this axis is responsible for several forms of muscular dystrophy. A unique case of congenital muscular dystrophy simulating a juvenile polymyositis in a muscle biopsy is presented. A profound reduction of alpha-dystroglycan and less pronounced secondary deficiency of alpha 2-laminin were found. All known forms of CMD were excluded, and the disorder was diagnosed as so far undescribed form of CMD. The mutation in a gene encoding the protein, that seems to play a role in a glycosylation of alpha-dystroglycan, is presumed.


Subject(s)
Muscular Dystrophies/congenital , Child , Diagnosis, Differential , Female , Humans , Immunohistochemistry , Muscle, Skeletal/chemistry , Muscle, Skeletal/pathology , Muscular Dystrophies/diagnosis , Muscular Dystrophies/genetics , Muscular Dystrophies/metabolism , Muscular Dystrophies/pathology
8.
Neoplasma ; 51(2): 77-83, 2004.
Article in English | MEDLINE | ID: mdl-15190415

ABSTRACT

Overexpression of HER-2/neu was described in pancreatic intraepithelial neoplasia (PanIN) and in invasive ductal adenocarcinoma of pancreas in a variable proportion of cases. The effects of HER-2/neu overexpression on mitogenic signalling and cell cycle progression were studied in breast luminal epithelial cells and mitogen activated protein kinase-dependent induction of p21(WAF1/CIP1) was found to be necessary for G1 phase progression. Overexpression of p21(WAF1/CIP1) was described as an early event in the development of PanIN by Biankin et al. (2001) and this finding was supported by our previous study that, moreover, did not confirm the possible role of activating K-ras mutations in the induction of p21(WAF1/CIP1) overexpression. Relationship between p21(WAF1/CIP1) expression and HER-2/neu status in PanIN lesions and ductal adenocarcinoma of the pancreas was investigated in our study. Expression levels of p21(WAF1/CIP1) and HER-2/neu were examined imunohistochemically and the amplification of HER-2/neu gene was evaluated by fluorescence in situ hybridisation in HER-2/neu overexpressing adenocarcinomas. Fourty nine pancreatic resection specimens from patients with invasive adenocarcinoma were included into the study. A large spectrum of PanIN lesions adjacent to the structures of infiltrating adenocarcinoma was also examined. The possible role of HER-2/neu in an induction of p21(WAF1/CIP1) overexpression was not confirmed and p21(WAF1/CIP1) overexpression seems to be HER-2/neu independent in pancreatic ductal adenocarcinoma according to our results. Increasing levels of HER-2/neu expression were demonstrated in pancreatic intraepithelial neoplasia and in 18.75% of pancreatic adenocarcinoma. The only 2 from 9 HER-2/neu overexpressing adenocarcinomas showed the amplification of HER-2/neu gene. Based on these results, the overexpression of HER-2/neu in pancreatic adenocarcinoma seems to be a result of increased transcription rather than gene amplification. Therefore HER-2/neu represents a good target for therapy of pancreatic adenocarcinoma only in isolated cases.


Subject(s)
Carcinoma in Situ/metabolism , Carcinoma, Pancreatic Ductal/metabolism , Cyclins/biosynthesis , Pancreatic Neoplasms/metabolism , Receptor, ErbB-2/biosynthesis , Adenocarcinoma/metabolism , Cell Cycle , Cell Differentiation , Cyclin-Dependent Kinase Inhibitor p21 , G1 Phase , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Pancreas/metabolism , Pancreas/pathology , Transcription, Genetic
9.
Pathol Res Pract ; 200(1): 59-65, 2004.
Article in English | MEDLINE | ID: mdl-15157052

ABSTRACT

Oncocytic cardiomyopathy is a rare arrhythmogenic disorder usually associated with female sex, difficult-to-control arrhythmias, or sudden death of infants and children. Morphologically, it is characterized by the presence of oncocytic cells, which are diffusely distributed or form the nodular structures within the myocardium, occasionally involving the valves, with a large number of mitochondria in cytoplasms. We present two cases of oncocytic cardiomyopathy. The first case had a fatal clinical outcome, and the other case was surgically treated. The nuclear expression of skeletal muscle transcription factor MyoD1 was demonstrated in the first case, supporting the theory that oncocytic cardiomyopathy is a conduction system developmental disorder. To confirm this hypothesis, it is necessary to further investigate myogenic transcription factor program in human cardiac conduction system cells.


Subject(s)
Cardiomyopathies/metabolism , Cardiomyopathies/pathology , Heart Defects, Congenital/metabolism , MyoD Protein/biosynthesis , Oxyphil Cells/pathology , Child , Female , Heart Defects, Congenital/pathology , Humans , Immunohistochemistry , Infant , Infant, Newborn , Microscopy, Electron , Myocardium/metabolism , Myocardium/pathology , Myocardium/ultrastructure
10.
Cesk Patol ; 40(1): 3-6, 2004 Jan.
Article in Czech | MEDLINE | ID: mdl-15035052

ABSTRACT

Marsh' classification of celiac disease or malabsorption syndrome sensu stricto is based on increased number of intraepithelial lymphocytes, as the first and constant sign/feature of the disease. Thereafter follow structural alterations of the mucous membrane, particularly of villous architecture, crypt height and enterocytes. According to the Marsh' classification, type 0 corresponds to normal mucous membrane, and type 1, the infiltrative type, is characterised by an increase in intraepithelial lymphocytes (IEL), which amount to more than 40 lymphocytes/100 enterocytes. Type 2 has normal villous architecture, an increase in IEL numbers and crypt hyperplasia. Type 3, the destructive type, is characterised by villous atrophy and may be divided into three sub-groups depending on the degree of the atrophy-mild, marked, and total (flat mucosa). Combination of these histopathological findings, patient's history and clinical course may result in the definition of six "states" of celiac disease. Marsh' classification is helpful for an early diagnosis of the disease and should be applied in any case of the bioptical examination of the malabsorption syndrome. The disadvantage of this system, applied on formol-paraffin tissue sections, is impossibility of revealing disacharidases (particularly lactase) deficiency. From this point of view, histochemical detection of disacharidases should accompany the bioptical examination of jejunal mucosa.


Subject(s)
Celiac Disease/diagnosis , Biopsy, Needle , Celiac Disease/classification , Celiac Disease/metabolism , Celiac Disease/pathology , Diagnosis, Differential , Humans , Intestinal Mucosa/chemistry , Intestinal Mucosa/pathology
11.
Cesk Patol ; 39(4): 168-73, 2003 Oct.
Article in Czech | MEDLINE | ID: mdl-14663927

ABSTRACT

Apoptosis plays a central role in the development and/or progression of cancer. There are several methods for detection of apoptotic cells in tissue sections including light and electron microscopy, in situ nick end-labeling (ISEL), TdT-mediated dUTP nick-end labeling (TUNEL) and immunohistochemical detection of proteins associated with apoptosis. Apoptosis was assessed by the monoclonal antibody M30 CytoDEATH (M30), which is specific for neo-epitope in cytokeratin 18 that becomes available at an early caspase cleavage during apoptosis. Expression of bcl-2 protein was evaluated, because bcl-2 protein plays an important role in the regulation of apoptosis. Twenty-six invasive ductal adenocarcinomas of the pancreas were studied immunohistochemically with antibodies M30 and bcl-2. The mean apoptotic index (AI, the percentage of apoptotic cells of the total tumor cells number) was 2.75%. High AI (> 10%) was observed in 4 cases of the 26 pancreatic carcinomas (15%). Protein bcl-2 was expressed in 3 cases (11.5%). The AI did not correlate with the expression of protein bcl-2. In conclusion, the detection of neo-epitope in cytokeratin 18 by monoclonal antibody M30 can be used for quantification of apoptotic cells with immunohistochemical techniques in tissue sections. It is a new approach to evaluate apoptosis in pancreatic carcinomas. The low positivity of bcl-2 expression in pancreatic adenocarcinomas suggests that bcl-2 protein does not play a central role in pancreatic tumorigenesis and cancer progression.


Subject(s)
Apoptosis , Carcinoma, Pancreatic Ductal/pathology , Pancreatic Neoplasms/pathology , Proto-Oncogene Proteins c-bcl-2/analysis , Adult , Aged , Aged, 80 and over , Carcinoma, Pancreatic Ductal/chemistry , Female , Humans , Immunohistochemistry , Keratins/analysis , Male , Middle Aged , Pancreatic Neoplasms/chemistry , Prognosis
12.
Neoplasma ; 50(5): 319-25, 2003.
Article in English | MEDLINE | ID: mdl-14628083

ABSTRACT

Overexpression of p21WAF1/CIP1 was recently described as an early event in the development of pancreatic intraepithelial neoplasia. Since activating K-ras mutations are described in more than 80% of pancreatic cancers and are known to increase intracellular levels of p21WAF1/CIP1 in experimental models, the possible role of activating K-ras mutations in an induction of the p21WAF1/CIP1 expression was investigated in our study. We examined 71 surgical specimens, 29 of chronic pancreatitis and 42 of invasive ductal adenocarcinoma both having a large spectrum of PanIN (pancreatic intraepithelial neoplasia) lesions. Expression of p53 and p21WAF1/CIP1 was examined immunohistochemically and codon 12 K-ras mutational analysis was performed using the very sensitive mutant-enriched PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) analysis. Our study demonstrated the overexpression of p21WAF1/CIP1 as an early event in the development of pancreatic intraepithelial neoplasia in the group of chronic pancreatitis and invasive adenocarcinoma as well. Overexpression of p21WAF1/CIP1 increased progressively from normal ducts through the spectrum of PanIN lesions to invasive carcinomas. The p53 overexpression increased again progressively according to the severity of the lesion and seems to be a later event in the development of pancreatic intraepithelial neoplasia if compared to p21WAF1/CIP1 expression. Our results confirmed also the possible p53 independent p21WAF1/CIP1 expression in some PanIN2, PanIN3 lesions and invasive carcinomas. K-ras mutations were not revealed in samples with only low grade PanIN lesions (PanIN1a and PanIN1b). K-ras mutations were detected in 69,4% adenocarcinomas and in only one case of chronic pancreatitis. Two codon 12 K-ras positive pancreatic carcinomas showed K-ras mutations in the surrounding normal pancreatic tissue. In adenocarcinomas, no statistically significant correlation was found between K-ras mutational status and p21WAF1/CIP1 and p53 expression, respectively. The possible role of activating K-ras mutations in an induction of p21WAF1/CIP1 expression was not confirmed in this study.


Subject(s)
Adenocarcinoma/genetics , Cyclins/genetics , Gene Expression Regulation, Neoplastic/genetics , Genes, p53 , Genes, ras , Mutation/genetics , Pancreatic Neoplasms/genetics , Pancreatitis/genetics , Adenocarcinoma/surgery , Chronic Disease , Cyclin-Dependent Kinase Inhibitor p21 , Humans , Neoplasm Invasiveness , Pancreatic Ducts/pathology , Pancreatic Ducts/physiology , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/surgery , Pancreatitis/surgery , Reference Values
13.
Vnitr Lek ; 49(8): 637-41, 2003 Aug.
Article in Czech | MEDLINE | ID: mdl-14518088

ABSTRACT

UNLABELLED: The Emery-Dreifuss muscular dystrophy is caused by muscular lesions and disorders of cardial rhythm and/or by cardiomyopathy. An autosomal dominant form is related to mutations of genes, which are coding for lamins A/C. GROUP AND METHODS: In the group A the authors examined 37 patients with the diagnosis of dilatation cardiomyopathy (DKMP) and the mean ejection fraction 28.4; 8.8%. In the group B of 13 patients a cardiac stimulator was implanted for a rhythm disorder. Both groups were subjected to cardiological, neurological, clinical and electromyographic (EMG) examinations. A muscle biopsy from m. vastus lateralis was made and the sample was evaluated by histology, histochemistry and immunohistochemistry. The coding sequences of genes for lamins were amplified by polymerase chain reaction and the products were analyzed by the DHPLC method (denaturing higher performance liquid chromatography). RESULTS: In the group A there was a clinically myopathic picture in three patients, while EMG examination revealed a myogenic finding in 12 patients and a marginally myogenic one in five patients. The histological finding in 12 patients was evaluated as myogenic and marginally myogenic in six. In one patient the mutation analysis revealed mutation in the gene for lamin A/C. A myogenic finding in this patient was determined by EMG as well as by histological examination and the autosomal dominant form of the Emery-Dreifuss muscular dystrophy was therefore diagnosed. In the group B one patient displayed a myopathic neurological finding and a myogenic finding during EMG. A subsequent mutation analysis revealed a mutation in the gene for lamin A/C. The case was therefore the autosomal dominant form of the Emery-Dreifuss muscular dystrophy. In the other patients the clinically marginal myopathic finding was observed once, a marginally myogenic finding during EMG was seen five times, histology and immunochemistry revealed a myogenic finding once and a marginally myogenic finding also once. The other findings were within normal range. CONCLUSIONS: A careful neurological examination including EMG determined symptoms of skeletal muscle myopathies in a surprisingly high percentage of our cardiological patients. This observation draws attention to the need of neurological examination in patients with DKMP in order to discovered disorder in this area in time. In two patients mutations in genes coding lamins A/C were detected. It would be useful to analyze also genes coding for other cytoskeletal proteins in the future.


Subject(s)
Cardiomyopathy, Dilated/genetics , Lamin Type A/genetics , Muscular Dystrophy, Emery-Dreifuss/genetics , Adult , DNA Mutational Analysis , Female , Humans , Male
14.
Vnitr Lek ; 49(7): 559-62, 2003 Jul.
Article in Czech | MEDLINE | ID: mdl-12931440

ABSTRACT

Present diagnostic possibilities virtually do not make it possible to diagnose early stages of pancreatic cancer. Likewise, it is very difficult to differentiate between pancreatic cancer and chronic pancreatitis. The methods of visualization are insufficiently sensitive and the determination of certain genes could enrich our diagnostic opportunities. Considerable attention in this direction has been devoted to the determination and evaluation of the presence of oncogene K-ras. Our initial experience with the determination of K-ras in preparations from patients with pancreatic cancer or with chronic pancreatitis confirmed that K-ras in an oncomarker associated with adenocarcinoma of pancreas, whereas in patients with chronic pancreatitis it occurs in about 10% of the examined samples.


Subject(s)
Adenocarcinoma/diagnosis , Genes, ras , Pancreatic Neoplasms/diagnosis , Biomarkers, Tumor/analysis , Chronic Disease , Diagnosis, Differential , Female , Humans , Male , Pancreatitis/diagnosis
15.
Cesk Patol ; 38(1): 18-23, 2002 Jan.
Article in Czech | MEDLINE | ID: mdl-11933457

ABSTRACT

Duchenne and Becker muscular dystrophies (DMD/BMD) are X-linked recessive disorders caused by mutations in the dystrophin gene. A large intragenic deletion has been described in about 65% of DMD/BMD patients. Mothers of affected males are DMD/BMD carriers in two thirds of the cases. Routine deletions detection in DMD/BMD males is performed using multiplex polymerase chain reaction (mPCR), RT-PCR with a protein truncation test (PTT) or using Southern blotting. In females the deletions detection is complicated by the presence of a normal gene copy on the second X-chromosome. We are presenting the diagnostic strategy using FISH for the deletions detection in the dystrophin gene of female DMD/BMD carriers. We have used a set of six cosmid probes for the detection of the most frequently deleted areas of the dystrophin gene from the Department of Human Genetics, Leiden University Medical Center. We have examined 14 mothers of DMD/BMD males with a deletion in the dystrophin gene identified using mPCR. Four mothers of affected males have been diagnosed as carriers of a deletion in the dystrophin gene. We have revealed no deletion mutations in the exons examined in a control group of four healthy females. No discrepancy has been found between the FISH analysis results and the results of mPCR. Our results indicate that FISH is an effective and direct method for the identification of DMD/BMD carriers and we suggest this method as a method of a first choice in the identification of DMD/BMD carriers.


Subject(s)
Genetic Carrier Screening , Muscular Dystrophy, Duchenne/genetics , Dystrophin/genetics , Female , Gene Deletion , Humans , In Situ Hybridization, Fluorescence , Male , Muscular Dystrophy, Duchenne/diagnosis , Reverse Transcriptase Polymerase Chain Reaction
16.
Cesk Patol ; 37(2): 69-71, 2001 Apr.
Article in Czech | MEDLINE | ID: mdl-11455917

ABSTRACT

An atypical case of congenital myopathy characterised by a low frequency of hypoplastic type 2A fibres, type 2B fibre deficiency and type 1 fibre predominance is reported. Our patients are siblings, a 10 year old girl and a 7 year old boy. Both children suffered from ophthalmoplegia and muscle weakness, and the boy also showed signs of psychomotoric retardation. A muscle biopsy from musculus trapezius has shown type 1 fibre predominance and hypoplastic type 2 fibres.


Subject(s)
Muscle Fibers, Fast-Twitch/pathology , Myopathies, Structural, Congenital/pathology , Child , Female , Humans , Male , Myopathies, Structural, Congenital/diagnosis , Myopathies, Structural, Congenital/genetics
17.
Neuromuscul Disord ; 11(4): 411-3, 2001 May.
Article in English | MEDLINE | ID: mdl-11369194

ABSTRACT

A screening for mutation in the X-linked Emery-Dreifuss muscular dystrophy (X-EMD) gene was performed among patients affected with severe heart rhythm defects and/or dilated cardiomyopathy. Patients were selected from the database of the Department of Cardiology of the University Hospital Brno. One patient presented a mutation in the X-EMD gene and no emerin in his skeletal muscle. The patient had a severe cardiac disease but a very mild muscle disorder that had not been diagnosed until the mutations was found. This case shows that mutations in X-EMD gene, as it was shown for autosomal-dominant EMD, can cause a predominant cardiac phenotype.


Subject(s)
Cardiomyopathies/genetics , Cardiomyopathies/physiopathology , Genetic Linkage , Heart Conduction System/physiopathology , Muscular Dystrophy, Emery-Dreifuss/genetics , Mutation , X Chromosome/genetics , Adult , Humans , Male , Membrane Proteins/deficiency , Muscle, Skeletal/metabolism , Muscle, Skeletal/physiopathology , Muscular Dystrophy, Emery-Dreifuss/metabolism , Muscular Dystrophy, Emery-Dreifuss/physiopathology , Nuclear Proteins , Thymopoietins/deficiency
18.
Neuromuscul Disord ; 11(2): 133-8, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11257468

ABSTRACT

The complete dystrophin mRNA sequence has been analyzed in 20 Duchenne muscular dystrophy and Becker muscular dystrophy patients. In 13 cases, deletions in mRNA were detected using reverse transcription-polymerase chain reaction and in another seven cases, point mutations were found using the protein truncation test. Sixteen patients diagnosed with Duchenne muscular dystrophy showed the presence of deletions or of nonsense point mutations. From four patients with the Becker muscular dystrophy phenotype, three cases were associated with deletions conserving the translational frame and one was associated with a nonsense mutation E1110X. In the case of the E1110X mutation, an alternative splicing of dystrophin mRNA (3485-3640del) was detected in this patient which included the E1110X mutation site (nucleotide 3536) and did not change the translation reading frame. Individual nonsense point mutations were characterized by sequence analysis, which showed five novel mutations with respect to those reported in the Cardiff Human Gene Mutation Database http://uwcm.web.cf.ac.uk/uwcm/mg/hgmd0.html and the Leiden muscular dystrophy pages http://www.dmd.nl/.


Subject(s)
Alternative Splicing/genetics , Codon, Nonsense/genetics , Dystrophin/genetics , Muscular Dystrophies/genetics , RNA, Messenger/analysis , Adolescent , Adult , Child , Child, Preschool , DNA Mutational Analysis , Dystrophin/metabolism , Humans , Immunohistochemistry , Muscle, Skeletal/metabolism , Muscle, Skeletal/pathology , Muscle, Skeletal/physiopathology , Muscular Dystrophies/metabolism , Muscular Dystrophies/physiopathology , Phenotype , Point Mutation/genetics , Reverse Transcriptase Polymerase Chain Reaction
19.
Vnitr Lek ; 47(2): 74-80, 2001 Feb.
Article in Czech | MEDLINE | ID: mdl-15635850

ABSTRACT

UNLABELLED: In recent years evidence is increasing on the usefulness of physical loads and controlled physical training in patients with chronic heart failure (CHSS). In the presented work the authors assessed changes of the functional capacity and muscular strength after training on a bicycle ergometer. The group comprised 38 patients with CHSS due to IHD or dilatation cardiomyopathy NYHA II-III, EF lower than 40%, with a peak oxygen consumption (pVO2) lower than 20 ml/kg/min. The group was subdivided in a random fashion to subjects participating in training (T) and the control group (K). The patients were subjected to clinical examination, examination by common laboratory methods, spiroergometry, dynamometry. By the puncture technique a specimen of the m. vastus lateralis was taken for histological and histochemical examination of the muscle. The patients trained on the bicycle ergometer three times per week for a period of eight weeks, one exercise session lasted 30 minutes and was at the level of the anaerobic threshold. After completion of the training period the examinations were repeated. RESULTS: Before the onset of training the groups did not differ in any indicators. After termination of training they increased in group T: pVO2 from 18.9 +/- 4.8 to 22.13 +/- 15.72 ml/kg/min. (p < 0.0004), the oxygen consumption at the level of the anaerobic threshold (VO2AT) from 13.4 +/- 3.4 to 15.96 < or = 3.75 ml/kg/min. (p < 0.0006), the respiratory quotient (RQ) from 0.93 +/- v0.09 to 0.97 +/- 0.006 (p < 0.05), the maximal tolerated load from 0.72 +/- 0.72 to 1.08 +/- 0.33 W/kg (p <0.002), the maximal voluntary contraction of the femoral quadriceps muscle (MVC START) from 291.2 +/- 70.1 to 328.1 +/- 66.0 N (p<0.01), the maximal voluntary contraction of this muscle after 20 mins. of repeated contractions (MVC END) from 157.6 +/- 109 to 290.1 +/- 64.9 N (p < 0.01), the decrease of the maximal contraction after 20 minutes of repeated contractions was from 52.8 +/- 32.1 to 12.4 +/- 5.0% (p < 0.01). After training there were statistically significant differences between groups in VO2AT (p < 0.01), in pVO2 (p < 0.03) and in the decrement of the maximal muscular contraction (p < 0.01). The authors found a trend towards normalization of the diameter of muscle fibres I and II and of their ratio. The ventilation equivalent for carbon dioxide VE/VCO2 during the maximal tolerated load correlated significantly with the systemic and pulmonary vascular resistance, with RQ, VO2AT, pVO2, with the maximal tolerated load and with the blood level of prostaglandin F. CONCLUSION: Controlled physical training in patients with CHSS was safe, led to a significant improvement of spiroergometric indicators, load tolerance and muscular strength. After training there was a trend towards normalization of pathological changes in skeletal muscle. Based on the authors' experience and findings of other authors it is advisable to recommend training as part of treatment of patients with CHSS.


Subject(s)
Exercise Therapy , Heart Failure/therapy , Muscle, Skeletal/physiopathology , Physical Fitness , Biopsy, Needle , Exercise Tolerance , Female , Heart Failure/pathology , Heart Failure/physiopathology , Humans , Male , Middle Aged , Muscle Contraction , Muscle, Skeletal/pathology , Oxygen Consumption
20.
Cesk Patol ; 37(4): 137-45, 2001 Nov.
Article in Czech | MEDLINE | ID: mdl-11813630

ABSTRACT

Complex diagnosis of muscular dystrophies including clinical, bioptical and molecular genetic approaches has been provided in a limited extent in this country. Our group of neurologists, pathologists and geneticists has examined approximately 240 patients suspected of having muscular dystrophies, mostly coming from Southern and Northern Moravia. The patients were sent to the examination most often from departments of neurology and clinical genetics, and less frequently from departments of internal medicine. According to the final diagnosis, the patients were divided into groups: with dystrophinopathies and carriers of dystrophinopathies (DMD/BMD), merosin deficient form of congenital muscular dystrophy, and Emery-Dreifuss muscular dystrophy including the carriers of this disease. Some relatives of patients with dystrophinopathies were also examined using the methods of segregation analysis. High proportion of the DMD/BMD patients can be detected by the methods of molecular genetics. Analysis of mRNA using RT PCR and PTT enables the detection of deletions, duplications, and point mutations in dystrophin gene and encompasses a larger diagnostic scope in comparison with examinations of DNA level by the multiplex PCR method from the peripheral blood which enables only deletion detections. Immunophenotyping of the dystrophin protein plays an important role especially using antibodies against carboxyterminal (DYS2) and rod domain (DYS1) of dystrophin. Deficient sarcolemmal expression of DYS2 and DYS1 reveals unambiguously a pathological dystrophin. On the other hand, less pronounced deficiencies in dystrophin expression in BMD patients and DMD/BMD carriers may not always be detected in muscle biopsies. In this case, it is necessary to supplement the examination by Western blotting and genotype analysis. The examination of patients with clinically diagnosed muscular dystrophy should start with a muscle biopsy which enables the estimation of presence and degree of structural changes. Application of antibodies against the components of DGC and emerin may reveal a deficiency in expression of these proteins. Immunohistochemical examination completed by Western blotting leads to the subsequent molecular genetic analysis of DNA or mRNA. Secondary deficiencies in expression of other DGC proteins are often revealed in muscle biopsies of dystrophinopathies and this fact must be taken into account in the evaluation of immunohistochemical findings. There is a possibility of replacement of invasive muscle biopsy by skin biopsy or buccal mucosal smears in cases of merosin and emerin deficiencies. Commercially available antibodies against merosin, emerin, calpain and sarcoglycans enable extensive identification and detailed classification of muscular dystrophies. Screening of the patients based on the application of methods described and discussed in this report is the task of the forthcoming period.


Subject(s)
Dystrophin/genetics , Muscular Dystrophies/genetics , Mutation , Adolescent , Adult , Biopsy , Blotting, Western , Child , Child, Preschool , Dystrophin/analysis , Female , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Infant , Male , Muscle, Skeletal/chemistry , Muscle, Skeletal/pathology , Muscular Dystrophies/diagnosis , Muscular Dystrophies/metabolism , Point Mutation , Polymerase Chain Reaction , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA , Sequence Deletion
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