Rare causes of acute appendicitis.

INTRODUCTION: A clinical diagnosis of acute appendicitis does not necessarily imply only inflammatory changes found upon histopathological examination. Even though appendiceal tumors are very rare, accounting for less than 4% of all gastrointestinal tumors‚ they need to be taken into account and require the right choices regarding subsequent onco-surgical management. METHODS: 1036 appendectomies were performed and 38 (3.7%) rare appendiceal tumor cases were identified at the department of Surgery in Pilsen from 1 January 2008 to 1 October 2018. The following text presents the difficult nature of the initial diagnosis, current therapy and principles of follow-up care in this relatively rare group of patients. CONCLUSION: Appendiceal tumors are very rare. Depending on the histopathological type of tumor, it is necessary to choose adequate therapy and also provide proper follow up care.

[Coincidence of colonic lymphoma and gallstone ileus - case report]. / Koincidence lymfomu tracníku a biliárního ileu - kazuistika.

INTRODUCTION: Primary colonic lymphoma is a very rare malignant disease of the gastrointestinal tract, accounting for 14% of all malignant diseases in this location. It is classified in the group of extranodal lymphomas; its long-term asymptomatic progression makes it different from common colorectal carcinomas making its diagnosis very difficult, more often accidental. Gallstone ileus is quite an uncommon complication of cholecystolithiasis diagnosed with difficulty. Up to 50% of cases are diagnosed during surgery. The obturated location depends on the size of the stone, location of the conjunction between the biliary and gastrointestinal tracts, and also on any preexisting stenosis due to another unknown pathology. CASE REPORT: We present a case of an 86-year-old man treated for acute diverticulitis with typical clinical symptoms. Following further examination (colonoscopy, computed tomography) revealed a tumour-like infiltration in the sigmoid colon wall and a voluminous polyp was suspected according to the colonoscopy. Computed tomography described an obstruction by a biliary stone tumbling through the cholecystocolonic fistula. Subsequent biopsy supported the suspected malignant etiology. The patient underwent resection of the sigmoid colon sec. Hartmann; an infiltration was found in the subhepatic space, which corresponded to the described fistulisation between the biliary tract and the colon. A large 40 mm gallstone was found in the resected sigmoid colon over the stenosis and the bowel wall showed diffuse thickening with several polyps; final histopathological assessment confirmed malignant lymphoma of the plasmocytoma type. No serious complications occurred in the postoperative period; after healing, the patient was transferred to hematooncology care. CONCLUSION: The article describes the presence of two rare diseases - colonic lymphoma and gallstone ileus. Clearly, without the biliary stone obstruction in the preexisting tumorous stenosis in the sigmoid colon, the malignant hematooncology disease would not have been diagnosed. KEY WORDS: primary colonic lymphoma - gallstone ileus - complication of the cholecystolithiasis - extranodal lymphoma - acute diverticulitis.

[Intestinal volvulus caused by the ingestion of magnet balls: unexpected risk in children]. / Strevní volvulus zpusobený pozitím magnetických kulicek: neocekávané riziko u detí.

INTRODUCTION: The occurrence of swallowed foreign bodies in the digestive system is a common problem in children with the highest incidence in children aged six months to five years. Most swallowed objects leave the human body per vias naturales while 10-20% of swallowed foreign bodies need to be removed with an endoscope. Serious and life-threatening situations are caused by the ingestion of foreign bodies in about 1% of all cases. CASE REPORT: The authors present a case of a two-year-old girl diagnosed with acute abdomen for which she was operated on. A small bowel volvulus and several intestinal fistulas were found intraoperatively. The cause of this finding was the ingestion of magnetic balls and a swallowed metal body drawn to them by magnetic force. CONCLUSION: If more than one magnetic body is ingested, it is necessary to admit the patient to hospital and to remove these foreign bodies using an endoscope. The position of the magnets which is not changing in a location inaccessible for an endoscope during 2448 hours is an indication for urgent operation.

Redesigning services for the management of vitreomacular traction and macular hole.

Vitreomacular traction (VMT) and VMT with macular hole (MH) are serious conditions, being associated with visual disturbance, for example, metamorphopsia, and diminished visual acuity (VA). Pars plana vitrectomy is the routine treatment for symptomatic VMT and VMT+MH. However, ocriplasmin has demonstrated favourable efficacy and safety in specific patient groups with VMT/MH and is now recommended as a treatment option for certain patients by the National Institute of Health and Care Excellence. This means that services for managing patients with VMT/MH may need to be revised, as patients can now potentially receive treatment earlier in the course of the disease. VMT triage clinics could provide a more efficient way of managing VMT/MH patients. Patient assessment should always include high-definition optical coherence tomography, as this is the most accurate means of assessing abnormalities in the vitreoretinal (VR) interface, and an accurate measurement of best-corrected VA. It has been proposed that patients with VMT+MH be managed as a routine 6-week referral, with the complete patient journey-from initial referral to treatment-taking no longer than 6 months. It is important that patients are entered onto VR surgical lists so that there is no delay if ocriplasmin treatment is unsuccessful. Patients will need appropriate counselling about the expected outcomes and possible side effects of ocriplasmin treatment. One-year follow-up data should be collected by treatment centres in order to evaluate the new VMT service.

[Chronic abdominal pain with a rare cause]. / Chronické bolesti bricha s raritní prícinou.

The authors use a case report of a female patient with chronic abdominal pain progressing postprandially as an example to demonstrate the complexity of the diagnostic process in patients with these complaints, as well as a surprising peroperative finding in which a small neuroendocrine tumour of the small intestine was the cause of the difficulties. The ensuing discussion also deals with other possible causes of chronic abdominal pain associated with eating disorders.

[Small intestine invagination in an adult]. / Invaginace tenkého streva v dospelosti.

Bowel intussusception in adulthood is relatively rare. It is the cause of bowel movement disorders in around 1-5% of cases. In contrast to intussusception in childhood, where the cause is usually unclear, in adulthood the unequivocal causes are known in 70-90% of cases. These predominantly include benign tumours of the small intestine. The authors describe 2 case reports, where small bowel intussusception was the cause of the bowel movement disorder and non-specific abdominal pain. This clinical entity must be kept in mind as the possible cause of non-specific abdominal pain in adulthood. If a malignancy is suspected, then the rules of oncological surgery should be followed.

[Delivery, and anal incontinence later in life]. / Porodní poranení a anální inkontinence v dlouhodobé perspektive.

OBJECTIVE: Evaluation of the mutual relationship between delivery and late anal incontinence. DESIGN: Review. SETTING: Department of Gynaecology and Obstetrics, Charles University and University Hospital Pilsen. SUMMARY: Anal incontinence is a symptom often referred to by women between the ages of 40 and 60. However, it seems, that only a small number of such cases might be related to obstetric perineal trauma. According to recent data, elective Caesarean section only plays a small protective role. Its effect is restricted to the first few years after delivery. With time, the function of the anal sphincter gradually deteriorates. Subsequent deliveries might contribute to this functional impairment. The long-term effect of forceps delivery is still not clear. The extent of anal sphincter trauma (particularly the defect of the internal anal sphincter) seems to have an impact on the development of anal incontinence, even years after the event. Overlooking defects of the anal sphincter is a cause of problems long after delivery. Given the unsatisfactory results of secondary overlapping, and also, relatively good preliminary effect of primary repair, careful observence of the recommended steps leading to the correct diagnostics of obstetric perineal trauma is crucial, as is adequate repair.

A single amino acid mutation alters the capsid protein electrophoretic double-band phenotype of the Plum pox virus strain PPV-Rec.

Plum pox virus (PPV) isolates differ by their capsid protein (CP) mobility in SDS-PAGE. These electrophoretic phenotypes are likely to result from post-translational modifications of the CP. We demonstrated that the CP mobility was solely determined by the CP N-terminal region. Sequence comparison pinpointed a possible role of mutations at position 66 in determining the CP phenotype of PPV-Rec isolates. Site-directed mutagenesis of a chimeric clone demonstrated that Gly(66) in the CP resulted in the double-band phenotype, while Arg(66) led to a single-band CP pattern, possibly by preventing the phosphorylation of a nearby Ser residue by steric hindrance.

[Significance of the TPS cytokeratin marker in the postoperative follow up of colorectal carcinoma patients]. / Význam cytokeratinového markeru TPS v pooperacním sledováiní nemocných s kolorektálním karcinomem.

AIM: Examination of tumour markers conducive to follow up of the patients with colorectal carcinoma. MATERIAL AND METHODS: The tumour markers were examined in the population of patients with primarily established and histologically verified colorectal adenocarcinoma. RESULTS: The resection therapy resulted in the decrease in post-operative CEA levels. There were no changes in pre- and post-operative CA 19-9 levels; unlike with post-operative TPS levels having been significantly increased, probably due to reparation processes resulting from the surgery. It can be concluded that pre- and post-operative CEA levels are the most suitable markers to check the effect of surgery. With a 95%-specificity for the establishment of recidives, the highest sensitivity was reached with TPS (83%); the sensitivities of the classical tumour markers CEA and CA 19-9 were significantly lower (41% and 25%, respectively). The results should be interpreted with caution due to a small number of relapses regarding a short follow up and rather local-regional character of the recidives. CONCLUSION: However, TPS seems to be a promising marker for the follow up of the patients with colorectal carcinoma. Thus, an ideal combination seems to be that of CEA and TPS.

Complete DNA sequence of the linear mitochondrial genome of the pathogenic yeast Candida parapsilosis.

The complete sequence of the mitochondrial DNA of the opportunistic yeast pathogen Candida parapsilosis was determined. The mitochondrial genome is represented by linear DNA molecules terminating with tandem repeats of a 738-bp unit. The number of repeats varies, thus generating a population of linear DNA molecules that are heterogeneous in size. The length of the shortest molecules is 30,922 bp, whereas the longer molecules have expanded terminal tandem arrays (nx738 bp). The mitochondrial genome is highly compact, with less than 8% of the sequence corresponding to non-coding intergenic spacers. In silico analysis predicted genes encoding fourteen protein subunits of complexes of the respiratory chain and ATP synthase, rRNAs of the large and small subunits of the mitochondrial ribosome, and twenty-four transfer RNAs. These genes are organized into two transcription units. In addition, six intronic ORFs coding for homologues of RNA maturase, reverse transcriptase and DNA endonucleases were identified. In contrast to its overall molecular architecture, the coding sequences of the linear mitochondrial DNA of C. parapsilosis are highly similar to their counterparts in the circular mitochondrial genome of its close relative C. albicans. The complete sequence has implications for both mitochondrial DNA replication and the evolution of linear DNA genomes.

Differentiation of the yeasts Williopsis, Zygowilliopsis and Komagataea by karyotypic and PCR analyses.

We used polymerase chain reaction with universal and microsatellite primers, and molecular karyotyping to evaluate the extent of divergence between the genomes of the yeasts currently assigned to the heterogeneous genus Williopsis. Pulsed-field gel electrophoresis of chromosomal DNAs indicates that Zygowilliopsis californica, Komagataea pratensis, Williopsis mucosa, Williopsis salicorniae species and Williopsis sensu stricto complex have clearly different karyotypes. In contrast, the latter six species, Williopsis saturnus, W. beijerinckii, W mrakii, W. suaveolens, W. subsufficiens and W. sargentensis, show similar banding patterns and practically cannot be differentiated on the basis of their karyotypes. The data revealed that a PCR method employing the universal primer N21 is appropriate for the distinction of Williopsis, Zygowilliopsis and Komagataea yeasts. Unique fingerprints were generated with this primer for all 10 species studied while strains of the same species showed nearly identical profiles. The data of UP-PCR are in good agreement with genetic classification and provide support for the species status of the yeasts composing the Williopsis sensu stricto complex. Microsatellite primer (GTG)5 allowing molecular typing of individual strains of the same species may be useful for investigating population structure of the saturn-spored yeasts.

Mitochondrial single-stranded DNA-binding proteins: in search for new functions.

During the evolution of the eukaryotic cell, genes encoding proteins involved in the metabolism of mitochondrial DNA (mtDNA) have been transferred from the endosymbiont into the host genome. Mitochondrial single-stranded DNA-binding (mtSSB) proteins serve as an excellent argument supporting this aspect of the endosymbiotic theory. The crystal structure of the human mtSSB, together with an abundance of biochemical and genetic data, revealed several exciting features of mtSSB proteins and enabled a detailed comparison with their prokaryotic counterparts. Moreover, identification of a novel member of the mtSSB family, mitochondrial telomere-binding protein of the yeast Candida parapsilosis, has raised interesting questions regarding mtDNA metabolism and evolution.

Electron microscopic analysis supports a dual role for the mitochondrial telomere-binding protein of Candida parapsilosis.

Linear mitochondrial genomes exist in several yeast species which are closely related to yeast that harbor circular mitochondrial genomes. Several lines of evidence suggest that the conversion from one form to another occurred accidentally through a relatively simple mechanism. Previously, we (L.T. & J.N.) reported the identification of the first mitochondrial telomere-binding protein (mtTBP) that specifically binds a sequence derived from the extreme end of Candida parapsilosis linear mtDNA, and sequence analysis of the corresponding nuclear gene MTP1 revealed that mtTBP shares homology with several bacterial and mitochondrial single-stranded (ss) DNA-binding (SSB) proteins. In this study, the DNA-binding properties of mtTBP in vitro and in vivo were analyzed by electron microscopy (EM). When M13 ssDNA was used as a substrate, mtTBP exhibited similar DNA binding characteristics as human mitochondrial SSB: mtTBP formed protein globules along the DNA substrate, and the bound proteins were randomly distributed, indicating that the binding of mtTBP to M13 ssDNA is not highly cooperative. EM analysis demonstrated that mtTBP is able to recognize the 5' single-stranded telomeric overhangs in their natural context. Using isopycnic centrifugation of mitochondrial lysates of C. papsilosis we show that mtTBP is a structural part of mitochondrial nucleoids of C. parapsilosis and is predominantly bound to the mitochondrial telomeres. These data support a dual role of mtTBP in mitochondria of C. parapsilosis, serving both as a typical mitochondrial SSB and as a specific component of the mitochondrial telomeric chromatin.

Quartz strip resonators as a temperature sensor.

The miniature frequency-temperature sensor in the form of a small quartz strip vibrating in the thickness-shear mode with the resonant frequency in the range from 4 to 8 MHz is considered. Y-cut strips rotated in the range from 0 degrees to 27 degrees are the subject of the study. The temperature coefficients of the resonance frequency for the different rotation angles are given. The different temperature dependence of the resonant frequency of the quartz temperature sensors vibrating on the fundamental and harmonic frequency of the thickness-shear modes is pointed out.

Extragenomic double-stranded DNA circles in yeast with linear mitochondrial genomes: potential involvement in telomere maintenance.

Although the typical mitochondrial DNA (mtDNA) is portrayed as a circular molecule, a large number of organisms contain linear mitochondrial genomes classified by their telomere structure. The class of mitochondrial telomeres identified in three yeast species, Candida parapsilosis, Pichia philodendra and Candida salmanticensis, is characterized by inverted terminal repeats each consisting of several tandemly repeating units and a 5' single-stranded extension. The molecular mechanisms of the origin, replication and maintenance of this type of mitochondrial telomere remain unknown. While studying the replication of linear mtDNA of C.parapsilosis by 2-D gel electrophoresis distinct DNA fragments composed solely of mitochondrial telomeric sequences were detected and their properties were suggestive of a circular conformation. Electron microscopic analysis of these DNAs revealed the presence of highly supertwisted circular molecules which could be relaxed by DNase I. The minicircles fell into distinct categories based on length, corresponding to n x 0.75 kb (n = 1-7). Similar results were obtained with two other yeast species (P.philodendra and C. salmanticensis) which possess analogous telomeric structure.

The respiratory complex I in yeast: isolation of a gene NUO51 coding for the nucleotide-binding subunit of NADH:ubiquinone oxidoreductase from the obligately aerobic yeast Yarrowia lipolytica.

We have isolated a gene NUO51 coding for a homologue of the nucleotide-binding subunit of mitochondrial respiratory chain linked NADH:ubiquinone oxidoreductase from the obligately aerobic yeast Yarrowia lipolytica. DNA sequencing revealed a 1464 bp open reading frame encoding a protein with predicted molar mass of about 53.7 kDa. The sequence is highly conserved with its counterparts from filamentous fungi and represents the first yeast homologue of the NADH-binding subunit (51 kDa) of the respiratory complex 1. In addition, PFGE and Southern hybridization analysis indicate that NUO51 is a single copy gene in the genome of Y. lipolytica. The expression of NUO51 by Northern blot analysis was also examined.

Isolation and expression of the gene encoding mitochondrial ADP/ATP carrier (AAC) from the pathogenic yeast Candida parapsilosis.

A gene homologous to Saccharomyces cerevisiae AAC genes coding for mitochondrial ADP/ATP carriers has been cloned from the pathogenic yeast Candida parapsilosis. A probe obtained by PCR amplification from C. parapsilosis DNA, using primers derived from the conserved transmembrane region of yeast ADP/ATP carriers, was used for screening of the C. parapsilosis genomic library. The cloned gene was sequenced and found to encode a polypeptide of 303 amino acids that shows homology with other yeast and fungal mitochondrial ADP/ATP carriers. The gene was designated CpAAC1 and was able to complement the growth phenotypes of S. cerevisiae double deletion mutant (Deltaaac2; Deltaaac3). The expression of the CpAAC1 gene was reduced under semi-anaerobic conditions and it was affected at normal aerobic conditions by the nature of carbon sources used for growth. Hybridization experiments indicate that C. parapsilosis possesses a single gene encoding a mitochondrial ADP/ATP carrier.

Linear DNA plasmid pPK2 of Pichia kluyveri: distinction between cytoplasmic and mitochondrial linear plasmids in yeasts.

The linear plasmids frequently found in plants and filamentous fungi are associated with mitochondria or chloroplasts. In contrast, all the linear plasmids known in yeasts are cytoplasmic elements. From a strain of the yeast Pichia kluyveri, we have isolated a new linear plasmid, pPK2, which was found to be associated with mitochondria. This 7.1 kilobase pairs-long DNA contained only two genes, which code for DNA and RNA polymerases, as judged from their nucleotide sequences translated by a mitochondrial genetic code. When we examined several recently isolated yeast plasmids for their subcellular localization, we found that two linear plasmids, pPH1 from Pichia heedii, as well as pPK1 from another strain of P. kluyveri, were also localized in mitochondria. These plasmids are the first examples of mitochondria-associated linear plasmids in yeast. All other linear plasmids we examined were of cytoplasmic origin. Whilst the cytoplasmic type linear plasmids were efficiently eliminated by ultraviolet irradiation of host cells, the mitochondria-associated plasmids were highly resistant. The mitochondrial pPK2 plasmid was rapidly lost by treatment of the host cells with ethidum bromide.

Mitochondrial telomere-binding protein from Candida parapsilosis suggests an evolutionary adaptation of a nonspecific single-stranded DNA-binding protein.

The mitochondrial genome in a number of organisms is represented by linear DNA molecules with defined terminal structures. The telomeres of linear mitochondrial DNA (mtDNA) of yeast Candida parapsilosis consist of tandem arrays of large repetitive units possessing single-stranded 5' extension of about 110 nucleotides. Recently we identified the first mitochondrial telomere-binding protein (mtTBP) that specifically binds a sequence derived from the extreme end of C. parapsilosis linear mtDNA and protects it from attack by various DNA-modifying enzymes (Tomáska, L'., Nosek, J., and Fukuhara, H. (1997) J. Biol. Chem. 272, 3049-3059). Here we report the isolation of MTP1, the gene encoding mtTBP of C. parapsilosis. Sequence analysis revealed that mtTBP shares homology with several bacterial and mitochondrial single-stranded DNA-binding proteins that nonspecifically bind to single-stranded DNA with high affinity. Recombinant mtTBP displays a preference for the telomeric 5' overhang of C. parapsilosis mtDNA. The heterologous expression of a mtTBP-GFP fusion protein resulted in its localization to the mitochondria but was unable to functionally substitute for the loss of the S. cerevisiae homologue Rimlp. Analysis of the MTP1 gene and its translation product mtTBP may provide an insight into the evolutionary origin of linear mitochondrial genomes and the role it plays in their replication and maintenance.

Drive level dependence of the resonant frequency in BAW quartz resonators and his modeling.

The influence of the excitation current on the resonant frequency and its mathematical description makes necessary the introduction of a nonlinear impedance characteristic of the piezoelectric resonator. This influence was modeled by the nonlinear electrical equivalent circuit; the equivalent series resistance and equivalent motional capacitance are taken to be functions of the amplitude of the excitation current by means of the relations derived in the work. The equivalent circuit was analyzed by the method of equivalent linearization. The relationships between the amplitudes of voltage applied on the AT-cut resonator and the first current harmonics or phase-frequency dependence of the excited resonator, respectively, are derived. Amplitude jumps and dynamic temperature change phenomena are discussed.