Spongious encephalopathy (1920–2010)

U radu se istražuju prve prionske bolesti od kojih je većina genetskog podrijetla. Uključuju točkaste mutacije (promjena jedno baznog para, change in a single base pair Adenine/Guanine, Thymin/Cytosine) DNA, insercija oktapeptida u N-ti dio prionskog proteina (3 do 216 oktapeptida), delecije (samo dva ili tri su poznata do sada). Tri ili više insercija potrebna za ovu bolest. To je 35 točkastih mutacija (najčešće su na kodonima 102, 178 i 200). Najnovija varijanta CJB, koja nastaje konzumacijom mesa zaraženog goveda, karakterizira polimorfizam Metionin/Metionon (M/M) na kodonu 129 u 98 posto slučajeva. U ostalih oblika prionske bolesti nema zabilježenih promjena u prionskom genomu. Točkaste mutacije karakterizira jedna promjena u jednom baznom paru od 109 postojećih u ljudskom genomu. Genetske prionske bolesti čine 10-15 posto svih slučajeva prionske bolesti. Ne-genetske prionske bolesti čine 85-90 posto slučajeva, a zajedno se javljaju u 1,5-2,5 slučaja na milijun stanovnika. Genetske prionske bolesti su istovremeno i infektivne. Patološki prionski protein (PrPSc) potreban je za postavljanje dijagnoze. Klinička dijagnoza genetskih i ne-genetskih prionskih bolesti čini se vrlo kompliciranom. U bolesnika s genetskim prionskim bolestima ponekad postoje anamnestički podaci o sličnim slučajevima koji su se pojavili u ovoj ili prijašnjim generacijama. Genetske prionske bolesti mogu se dijagnosticirati analizom baznih parova laboratorijskom metodom ili automatskim uređajem ili citokemijom, metodom lančane reakcije polimerazom, Western blot metodom, imunoenzimskim testom (ELISA). Za izvođenje ovih metoda potrebno je konstruirati tzv. „primere“ ili početnice za kodone 102, 178 i 200. Rade se i obdukcije, biopsije, elektroneurodijagnostika i analiza cerebrospinalnih markera prionskih bolesti. Diferencijalna dijagnostika na druge bolesti je također vrlo važna. Najviše publikacija objavio je Prusiner, koji je dobio i Nobelovu nagradu. On je nedavno promijenio svoje mišljenje o eliminaciji proteina X i prihvatio tezu o utjecaju stranih čimbenika. Patološki prionski protein PrPSc ne može nastati iz prionskog proteina PrPC jer PrPSc, kao protein, ne može stvarati nove proteine. PrPSc je proizvod gena, što znači da je nukleoprotein. U radu smo sažeto prikazali njegove ideje o genetskim prionskim bolestima. Infektivnost genetskih i ne-genetskih prionskih bolesti čini se vrlo niska. U posljednjih 40 godina analizirana je kultura tkiva: mnogo puta je bila pozitivna i uzročnik je mogao proći “pasaže”. Godine 2007. objavljen je rad o virusnoj etiologiji prionskih bolesti. Međutim, mnogi sojevi otkriveni do danas mogli su se uspoređivati samo elektronskim mikroskopiranjem. Pronađene su čestice veličine 20 do 50 nanometra, koje su se smatrale virusima, ali usporedba nije bila moguća. Nekoliko drugih neurotropnih virusa također je detektirano, čime se zakomplicirala dijagnostika prionskog uzročnika. Potrebna su daljnja istraživanja kulture tkiva, što je razvidno iz brojne do sada objavljene literature.We have studied the first prion diseases of which most cases were of genetic origin. They include point mutations (change in a single base pair Adenine/Guanine, Thymin/Cytosine) in the DNA, insertions of octapeptides in the N-part of the prion protein (3 to 216 octapeptide) and deletions (only two or three have been known until now). Three or more insertions are needed for the disease. They are 35 point mutations (the most frequent are at codon 102, 178 and 200). The newest variant CJD, which is caused by eating infected meat from infected beef is characterized by polimorphism Methionine/Methionone (M/M) at codon 129 in 98 percent of cases. The other cases of prion disease have no change in the prion genome. Point mutations are characterized by a single change in one base pair of 109 available in the human genome. Genetic prion diseases make up to 10-15 percent of all prion disease cases. Non genetic prion diseases are 85-90 percent; they together make up to 1,5-2,5 per million of inhabitants. Genetic prion diseases are simultaneously also infectious. PrPSc is needed for the diagnosis. Clinical diagnosis of genetic and nongenetic prion diseases appears very complicated. Genetic disease has sometimes anamnestic information on similar cases appearing in this or earlier generation. Genetic prion disease can be diagnosed by the study of base pairs by a laboratory method or by an automatic device or by Cytochemistry, Polymerase chain reaction, Western blot, Enzyme immunoassay (ELISA). Genetic methods need primers for the codon 102, 178 and 200. There are also autopsy, biopsy, electroneurodiagnostic and substances in the cerebrospinal fluid. The differential diagnostic to other diseases is very important. Most publications are from Prusiner, who received the Nobel prize. He changed recently his mind in eliminating the protein X and accepted clearly effects of foreign factors. PrPSc cannot originate from PrPC because both are proteins. The PrPSc is a product of the gene, i.e. that means it is nucleoprotein. We have summarized his ideas on genetic prion disease in the text. The infectivity of genetic and nongenetic prion diseases appears very low. The last 40 years tissue culture was tried: they were many times positive and the agents could be passaged. In 2007 a publication appeared as the virus of prion diseases was found. But many strains detected until now could only be compared with electron microscopic appearance. 20 to 50 nanometer great formations were found but the tissue itself did not function and a comparison was not possible. Several other neurotropic viruses were also found and this complicates the diagnosis of the prion agent. The tissue culture studies should be helped as evident from numerous publications in the world literature

Bovine Spongiform Encephalopathy (BSE) and Milk

Bovina spongiformna encefalopatija (BSE) je prionska bolest goveda, koja se pojavila 1985. godine u Velikoj Britaniji i izazvala veliku epidemiju izrokovanu hranom. Oboljelo je više od milijun životinja. Bolest se širila izvozom britanskih prehrambenih proizvoda za goveda (mesno i koštano brašno), najviše u europske zemlje, zatim Kanadu, Sjedinjene Američke Države i Japan. BSE je prenosiva na ljude konzumacijom inficiranog mesa; više od 160 slućajeva ove »varijante« Creutzfeldt-Jacobove bolesti je bila potvrđena u Velikoj Britaniji, 26 u Francuskoj i rijetki slučajevi u drugim zemljama. Konatalna infekcija u potomaka inficiranih goveda se javlja u nekih 10 %. Mlijeko je od ogromne važnosti u ljudskoj prehrani, osobito djece, a infektivnost mlijeka u ovom času još nije sasvim jasna, i premda je malo vjerojatna, ipak najnovija istraživanja pokazuju, da je moguća u određenim uvjetima, i stoga su potrebna dalja istraživanja, te epidemiološke mjere za izolaciju mogućih rizičnih životinja. Za jednu drugu sličnu prionsku bolest, a to je scrapie, infektivnost mlijeka je dokazana. Situacija na svjetskom tržištu mlijeka je danas kaotična i zahtijevala bi usku suradnju odgovornih političara i ekonomista, uz stručni nadzor veterinara i liječnika u svijetu i u Hrvatskoj.BSE, a prion disease of cattle, started about in 1985 and caused a large food epidemic in Great Britain with over a million of infected animals. The disease has spread, by British foodstuff export, involving most of the European countries, Canada, United States of America and Japan. BSE was transmissible for humans by infected meat consumation; over 160 cases of this »variant« Creutzfeldt-Jacob disease were confirmed in Great Britain, 26 in France and rare cases in many other countries. Connatal infection in cattle ocurrs in some 10 percent. Milk appears of enormous importance for humans in general, but particularly for children. Its BSE infectivity has not been clear at present as shown by recent studies in another similar prion disease, scrapie. The situation in the world milk market appears actually chaotic requiring a close cooperation between authorithies in politic and economy as well as between veterinary and human medical officers studying the situation in Croatia

Factor interaction analysis for chromosome 8 and DNA methylation alterations highlights innate immune response suppression and cytoskeletal changes in prostate cancer

BACKGROUND: Alterations of chromosome 8 and hypomethylation of LINE-1 retrotransposons are common alterations in advanced prostate carcinoma. In a former study including many metastatic cases, they strongly correlated with each other. To elucidate a possible interaction between the two alterations, we investigated their relationship in less advanced prostate cancers. RESULTS: In 50 primary tumor tissues, no correlation was observed between chromosome 8 alterations determined by comparative genomic hybridization and LINE-1 hypomethylation measured by Southern blot hybridization. The discrepancy towards the former study, which had been dominated by advanced stage cases, suggests that both alterations converge and interact during prostate cancer progression. Therefore, interaction analysis was performed on microarray-based expression profiles of cancers harboring both alterations, only one, or none. Application of a novel bioinformatic method identified Gene Ontology (GO) groups related to innate immunity, cytoskeletal organization and cell adhesion as common targets of both alterations. Many genes targeted by their interaction were involved in type I and II interferon signaling and several were functionally related to hereditary prostate cancer genes. In addition, the interaction appeared to influence a switch in the expression pattern of EPB41L genes encoding 4.1 cytoskeleton proteins. Real-time RT-PCR revealed GADD45A, MX1, EPB41L3/DAL1, and FBLN1 as generally downregulated in prostate cancer, whereas HOXB13 and EPB41L4B were upregulated. TLR3 was downregulated in a subset of the cases and associated with recurrence. Downregulation of EPB41L3, but not of GADD45A, was associated with promoter hypermethylation, which was detected in 79% of carcinoma samples. CONCLUSION: Alterations of chromosome 8 and DNA hypomethylation in prostate cancer probably do not cause each other, but converge during progression. The present analysis implicates their interaction in innate immune response suppression and cytoskeletal changes during prostate cancer progression. The study thus highlights novel mechanisms in prostate cancer progression and identifies novel candidate genes for diagnostic and therapeutic purposes. In particular, TLR3 expression might be useful for prostate cancer prognosis and EPB41L3 hypermethylation for its detection

Brady- and tachyarrhythmias detected by continuous rhythm monitoring in paroxysmal atrial fibrillation

Objective: Atrial fibrillation (AF) is associated with adverse events including conduction disturbances, ventricular arrhythmias and sudden death. The aim of this study was to examine brady- and tachyarrhythmias using continuous rhythm monitoring in patients with paroxysmal self-terminating AF (PAF). Methods: In this multicentre observational substudy to the Reappraisal of Atrial Fibrillation: interaction between hyperCoagulability, Electrical remodelling and Vascular destabilisation in the progression of AF (RACE V), we included 392 patients with PAF and at least 2 years of continuous rhythm monitoring. All patients received an implantable loop recorder, and all detected episodes of tachycardia ≥182 beats per minute (BPM), bradycardia ≤30 BPM or pauses ≥5 s were adjudicated by three physicians. Results: Over 1272 patient-years of continuous rhythm monitoring, we adjudicated 1940 episodes in 175 patients (45%): 106 (27%) patients experienced rapid AF or atrial flutter (AFL), pauses ≥5 s or bradycardias ≤30 BPM occurred in 47 (12%) patients and in 22 (6%) patients, we observed both episode types. No sustained ventricular tachycardias occurred. In the multivariable analysis, age &gt;70 years (HR 2.3, 95% CI 1.4 to 3.9), longer PR interval (HR 1.9, 1.1-3.1), CHA2DS2-VASc score ≥2 (HR 2.2, 1.1-4.5) and treatment with verapamil or diltiazem (HR 0.4, 0.2-1.0) were significantly associated with bradyarrhythmia episodes. Age &gt;70 years was associated with lower rates of tachyarrhythmias. Conclusions: In a cohort exclusive to patients with PAF, almost half experienced severe bradyarrhythmias or AF/AFL with rapid ventricular rates. Our data highlight a higher than anticipated bradyarrhythmia risk in PAF. Trial registration number: NCT02726698.</p

Brady- and tachyarrhythmias detected by continuous rhythm monitoring in paroxysmal atrial fibrillation

Objective: Atrial fibrillation (AF) is associated with adverse events including conduction disturbances, ventricular arrhythmias and sudden death. The aim of this study was to examine brady- and tachyarrhythmias using continuous rhythm monitoring in patients with paroxysmal self-terminating AF (PAF). Methods: In this multicentre observational substudy to the Reappraisal of Atrial Fibrillation: interaction between hyperCoagulability, Electrical remodelling and Vascular destabilisation in the progression of AF (RACE V), we included 392 patients with PAF and at least 2 years of continuous rhythm monitoring. All patients received an implantable loop recorder, and all detected episodes of tachycardia ≥182 beats per minute (BPM), bradycardia ≤30 BPM or pauses ≥5 s were adjudicated by three physicians. Results: Over 1272 patient-years of continuous rhythm monitoring, we adjudicated 1940 episodes in 175 patients (45%): 106 (27%) patients experienced rapid AF or atrial flutter (AFL), pauses ≥5 s or bradycardias ≤30 BPM occurred in 47 (12%) patients and in 22 (6%) patients, we observed both episode types. No sustained ventricular tachycardias occurred. In the multivariable analysis, age &gt;70 years (HR 2.3, 95% CI 1.4 to 3.9), longer PR interval (HR 1.9, 1.1-3.1), CHA2DS2-VASc score ≥2 (HR 2.2, 1.1-4.5) and treatment with verapamil or diltiazem (HR 0.4, 0.2-1.0) were significantly associated with bradyarrhythmia episodes. Age &gt;70 years was associated with lower rates of tachyarrhythmias. Conclusions: In a cohort exclusive to patients with PAF, almost half experienced severe bradyarrhythmias or AF/AFL with rapid ventricular rates. Our data highlight a higher than anticipated bradyarrhythmia risk in PAF. Trial registration number: NCT02726698.</p