Portal hypertension is the main driver of liver stiffness in advanced liver cirrhosis.

Liver stiffness (LS) is a novel non-invasive parameter widely used in clinical hepatology. LS correlates with liver fibrosis stage in non-cirrhotic patients. In cirrhotic patients it also shows good correlation with Hepatic Venous Pressure Gradient (HVPG). Our aim was to assess the contribution of liver fibrosis and portal hypertension to LS in patients with advanced liver cirrhosis. Eighty-one liver transplant candidates with liver cirrhosis of various aetiologies underwent direct HVPG and LS measurement by 2D shear-wave elastography (Aixplorer Multiwave, Supersonic Imagine, France). Liver collagen content was assessed in the explanted liver as collagen proportionate area (CPA) and hydroxyproline content (HP). The studied cohort included predominantly patients with Child-Pugh class B and C (63/81, 77.8%), minority of patients were Child-Pugh A (18/81, 22.2%). LS showed the best correlation with HVPG (r=0.719, p< 0.001), correlation of LS with CPA (r=0.441, p< 0.001) and HP/Amino Acids (r=0.414, p< 0.001) was weaker. Both variables expressing liver collagen content showed good correlation with each other (r=0.574, p<0.001). Multiple linear regression identified the strongest association between LS and HVPG (p < 0.0001) and weaker association of LS with CPA (p = 0.01883). Stepwise modelling showed minimal increase in r2 after addition of CPA to HVPG (0.5073 vs. 0.5513). The derived formula expressing LS value formation is: LS = 2.48 + (1.29 x HVPG) + (0.26 x CPA). We conclude that LS is determined predominantly by HVPG in patients with advanced liver cirrhosis whereas contribution of liver collagen content is relatively low.

Acute toxic effects of telmisartan in spontaneously hypertensive rats fed a high fructose diet.

Telmisartan is an angiotensin receptor blocker (ARB) and a selective peroxisome proliferator activated receptor gamma (PPARG) modulator. Recently, we tested metabolic effects of telmisartan (5 mg/kg body weight) in spontaneously hypertensive rats (SHR) fed a diet containing 60 % fructose, a widely used model of the metabolic syndrome. Surprisingly, we observed acute toxic effects of telmisartan. Rats lost body weight rapidly and died within 2 to 3 weeks due to bleeding into the upper gastrointestinal tract. SHR fed a high fructose diet and treated with telmisartan exhibited rapid decrease in blood pressure when compared to the SHR fed a high fructose diet and treated with valsartan. Concentrations of both unconjugated telmisartan and telmisartan glucuronide in the liver of SHR rats fed a high fructose diet were approximately 4 fold higher when compared to Brown Norway (BN) rats fed the same diet. Plasma concentrations of unconjugated telmisartan in the SHR were about 5 fold higher when compared to BN rats while plasma levels of telmisartan glucuronide were similar between the strains. Testing of other rat strains, diets, and the ARB valsartan showed that toxic effects of telmisartan in combination with high fructose diet are specific for the SHR. These results are consistent with the possibility that in some circumstances, SHR are predisposed to telmisartan toxicity possibly because of a genetically determined disturbance in telmisartan metabolism.

Aldehyde dehydrogenase 2 polymorphism affects the outcome of methanol poisoning in exposed humans.

As the susceptibility of humans to xenobiotics often depends on genetic factors, we assumed that ADH1B and ALDH2 genetic variants may affect susceptibility to the acute methanol exposure. To evaluate the role of genetic variants of enzymes involved in methanol catabolism in humans, we analysed ADH1B (rs1229984) and ALDH2 (rs441) polymorphisms in 50 adults who survived acute methanol poisoning, 246 individuals with alcoholic liver cirrhosis, and in 545 healthy controls. GG homozygotes of ADH1B were more common among methanol-poisoned patients (98%) and among patients with alcoholic liver cirrhosis (98%) than among healthy controls (90%) (P = 0.08 and < 0.001, respectively). Minor C allele carriers of the ALDH2 were significantly more common among methanol-poisoned persons (46%) than among patients with alcoholic liver cirrhosis or healthy controls (31% in both groups, P < 0.05 and 0.025, respectively); the odds ratios were 1.89 (95% CI 1.02-3.52) and 1.94 (1.08-3.48), respectively. As there was a substantial amount of subjects with alcohol abuse between both groups of patients, ADH1B is unlikely to affect the susceptibility to methanol poisoning. By contrast, the genetic variant of the ALDH2 enzyme seems to specifically affect the susceptibility to methanol in acutely exposed humans and potentially plays a role in the outcome of methanol poisoning.

Large copy-number variations in patients with statin-associated myopathy affecting statin myopathy-related loci.

Some patients are susceptible to statin-associated myopathy (SAM) either because of genetic variations affecting statin uptake and metabolism, or because they predispose their carriers to muscular diseases. Among the frequent variants examined using the genome-wide association study approach, SLCO1B1 c.521T>C represents the only validated predictor of SAM in patients treated with high-dose simvastatin. Our aim was to ascertain the overall contribution of large copy-number variations (CNVs) to SAM diagnosed in 86 patients. CNVs were detected by whole genome genotyping using Illumina HumanOmni2.5 Exome BeadChips. Exome sequence data were used for validation of CNVs in SAM-related loci. In addition, we performed a specific search for CNVs in the SLCO1B region detected recently in Rotor syndrome subjects. Rare deletions possibly contributing to genetic predisposition to SAM were found in two patients: one removed EYS associated previously with SAM, the other was present in LARGE associated with congenital muscular dystrophy. Another two patients carried deletions in CYP2C19, which may predispose to clopidogrel-statin interactions. We found no common large CNVs potentially associated with SAM and no CNVs in the SLCO1B locus. Our findings suggest that large CNVs do not play a substantial role in the etiology of SAM.

The response of hepatic transcriptome to dietary cholesterol in Prague hereditary hypercholesterolemic (PHHC) rat.

To understand the pathogenesis of hypercholesterolemia in Prague hereditary hypercholesterolemic (PHHC) rat, we analyzed the response of hepatic transcriptome to dietary cholesterol in PHHC and control Wistar rats. Male PHHC and Wistar rats were fed chow (C), 5 % fat (palm kernel oil) (CF) or 1 % cholesterol + 5 % fat (CHOL) diet for three weeks. Hepatic transcriptome was analyzed using Affymetrix GeneChip arrays. No differences were found in the effect of both control diets (C and CF) on lipid metabolism and gene expression of 6500 genes. Therefore, these data were pooled for further analysis. Dietary cholesterol induced accumulation of cholesterol and triacylglycerols in the liver in both strains and hypercholesterolemia in PHHC rats. However, there were no differences in response of hepatic transcriptome to CHOL diet. On the other hand, several genes were found to be differently expressed between both strains independently of the diet. Two of those genes, Apof and Aldh1a7, were studied in more detail, and their role in pathogenesis of hypercholesterolemia in PHHC rats could not been corroborated. In conclusion, the hypercholesterolemia in PHHC rats is due to physiological response of hepatic transcriptome to dietary cholesterol in different genetic background.

HNF-4α regulates expression of human ornithin carbamoyltransferase through interaction with two positive cis-acting regulatory elements located in the proximal promoter.

OTC encodes ornithine carbamoyltransferase, mitochondrial matrix enzyme involved in the synthesis of urea. The tissue-specific expression of OTC in the liver and intestine is dependent on the interaction of OTC promoter with an upstream enhancer. HNF-4 and C/EBPß are crucial for this interaction in the rat and mouse. In the present study we focused on characterization of elements involved in the regulation of OTC transcription in human. Using a set of 5'-deleted promoter mutants in a reporter assay we identified two positive cis-acting regulatory elements located at c.-105 and c.-136 within the human OTC promoter. Both are essential for the transcriptional activity of the promoter itself and for the interaction with the enhancer. Protein binding at the corresponding sites was confirmed by DNase I footprinting. Electromobility shift assay with a specific competitor and anti-HNF-4α antibody identified the DNA-protein binding sites as HNF-4α recognition motifs. A third HNF-4α binding site has been found at the position c.-187. All three HNF-4α binding sites are located within 35 bp upstream of the transcription start sites at positions c.-95, c.-119 (major) and c.-169 (minor). A series of C/EBPß recognition motifs was identified within the enhancer. Involvement of C/EBPß and HNF-4α in the promoter-enhancer interaction is further supported by a massive DNAprotein interaction observed in the footprinting and EMSA assays. Since the OTC promoter lacks general core promoter elements such as TATA-box or initiators in standard positions, HNF-4α most likely plays an essential role in the initiation of OTC transcription in human.

[Neonatal hyperbilirubinemia and molecular mechanisms of jaundice]. / Vrozené hyperbilirubinemie a molekulární mechanizmy zloutenky.

The introductory summarises the classical path of heme degradation and classification of jaundice. Subsequently, a description of neonatal types of jaundice is given, known as Crigler Najjar, Gilberts, DubinJohnson and Rotor syndromes, emphasising the explanation of the molecular mechanisms of these metabolic disorders. Special attention is given to a recently discovered molecular mechanism of the Rotor syndrome. The mechanism is based on the inability of the liver to retrospectively uptake the conjugated bilirubin fraction primarily excreted into the blood, not bile. A reduced ability of the liver to uptake the conjugated bilirubin contributes to the development of hyperbilirubinemia in common disorders of the liver and bile ducts and to the toxicity of xenobiotics and drugs using transport proteins for conjugated bilirubin.

Ornithine carbamoyltransferase deficiency: molecular characterization of 29 families.

Ornithine carbamoyltransferase deficiency is the most common inherited defect of the urea cycle. We examined 28 male and 9 female patients from 29 families and identified 25 distinct mutations in OTC, 14 of which were novel. Three novel missense mutations (p.Ala102Pro, p.Pro158Ser, p.Lys210Glu) and a novel deletion of the Leu43 are not directly involved either in the enzyme active site or in the intersubunit interactions; however, the mutations include conserved residues involved in intramolecular interaction network essential for the function of the enzyme. Three novel large deletions - a 444 kb deletion affecting RPGR, OTC and TSPAN7, a 10 kb-deletion encompassing OTC exons 5 and 6 and a 24.5 kb-deletion encompassing OTC exons 9 and 10 - have probably been initiated by double strand breaks at recombination-promoting motifs with subsequent non-homologous end joining repair. Finally, we present a manifesting heterozygote carrying a hypomorphic mutation p.Arg129His in combination with unfavorably skewed X-inactivation in three peripheral tissues.

[Evaluation of variants of unknown significance in the BRCA2 gene]. / Hodnocení variant nejasného významu v genu BRCA2.

BACKGROUND: Endogenous processes and exogenous agents cause constant DNA damage. DNA double-strand breaks are among the most serious types of damage. They are mainly repaired by homologous recombination, where the BRCA2 protein plays a dominant role. Heterozygous germline BRCA2 mutations predispose to breast, ovarian, pancreatic and other types of cancer. The presence of a pathogenic mutation in patients or their family members warrants close surveillance and prophylactic surgery. Apart from clearly pathogenic mutations, variants leading only to a single amino acid substitution are often identified. Since the influence of these variants on cancer risk is unknown, they represent a major clinical problem. AIMS: The aim of this paper is to summarize the current possibilities of predicting pathogenicity of BRCA2 variants. In some cases, genetic methods are able to classify variants with high probability; however, their use is often limited by low frequency of the variants or inaccessibility of samples for mRNA isolation or DNA from family members. Alternatively, functional assays performed in various cellular models may be employed. Multiple functional tests and cellular models are presented and characterized, including their advantages and limitations. A new model of human syngeneic cell lines developed by the authors is presented, in which one BRCA2 allele is deleted and the variant is introduced into the other allele by homologous recombination. This model has the potential to evaluate function of variants without some of the unwanted effects of the other models. Currently, this model is being applied to variants identified in patients with hereditary cancer predisposition in the Masaryk Memorial Cancer Institute. CONCLUSION: Functional assays in cellular models including a new model of syngeneic cell lines described by the authors have a great potential in evaluating clinical importance of unclassified variants in the BRCA2 gene, especially in cases where genetic tests are not applicable.

Enhancement of YBCO thin film thermal stability under 1 ATM oxygen pressure by intermediate Cu2O nanolayer.

The melting process of YBa(2)Cu(3)O(x) (YBCO or Y123) films under an oxygen atmosphere was observed in situ by means of high-temperature optical microscopy. The films were classified by pole figure measurement as c-axis oriented, with two different in-plane orientations (denoted as 0 and 45 degrees). In the 45 degrees-oriented films, electron diffraction and high-resolution transmission electron microscopy (HRTEM) detected an intermediate Cu(2)O nanolayer in the vicinity of the interface. The melting mode and the thermal stability of the YBCO thin films with different in-plane orientations were greatly influenced by oxygen partial pressure. Notably, the thermal stability of the 45 degrees-oriented YBCO films dramatically grew with increasing oxygen partial pressure. We attributed this effect to a change in the intermediate Cu(2)O nanolayer thermal stability. We conclude and suggest that the thermal stability of YBCO films can be significantly enhanced by inserting a Cu(2)O buffer nanolayer.

Role of common canalicular transporter gene variations in aetiology of idiopathic gallstones in childhood.

Variations in genes encoding canalicular transportes, for biliary lipids may affect concentrations of biliary lipids in bile and promote cholesterol crystallization and gallstone formation. In our study we investigated the contribution of heterozygosity for common variations considered either potentially pathogenic or susceptibility alleles for cholesterol cholelithiasis in adults (c.523A>G (p.Thr175Ala) and c.1954A>G (p.Arg652Gly) in ABCB4, c.1331T>C (p.Val444Ala) in ABCB11 and c.55 G>C (p.Asp19His) in ABCG8) to the aetiology of paediatric idiopathic gallstone disease. Genotyping was performed in 35 paediatric subjects with idiopathic gallstones with positive family history for gallstones and 150 population controls. The ABCB4 variant p.Thr175Ala was found only in the controls, not in the patients. The frequency of the remaining three variant alleles and the corresponding genotypes did not differ between patients and controls. We conclude that the studied common variations in genes encoding canalicular transporters known to contribute to genetic predisposition to cholesterol gallstones in adulthood do not contribute specifically to the aetiology of paediatric idiopathic gallstones.

Regulation of diurnal variation of cholesterol 7alpha-hydroxylase (CYP7A1) activity in healthy subjects.

Cholesterol 7alpha-hydroxylase (CYP7A1), the key regulatory enzyme of bile acid synthesis, displays a pronounced diurnal variation. To better understand the regulation of CYP7A1 activity, three day-long examinations were carried out in 12 healthy men. The concentrations of 7alpha-hydroxycholest-4-en-3-one (C4), a surrogate marker of CYP7A1 activity, bile acids (BA), insulin, glucose, nonesterified fatty acids, triglycerides, and cholesterol were measured in serum in 90-min intervals from 7 AM till 10 PM. To lower and to increase BA concentration during the study, the subjects received cholestyramine and chenodeoxycholic acid (CDCA), respectively, in two examinations. No drug was used in the control examination. There was a pronounced diurnal variation of C4 concentration with a peak around 1 PM in most of the subjects. The area under the curve (AUC) of C4 concentration was five times higher and three times lower when subjects were treated with cholestyramine and CDCA, respectively. No relationship was found between AUC of C4 and AUC of BA concentration, but AUC of C4 correlated positively with that of insulin. Moreover, short-term treatment with cholestyramine resulted in about 10 % suppression of glycemia throughout the day. Our results suggest that insulin is involved in the regulation of diurnal variation of CYP7A1 activity in humans.

[Fluorescence cystoscopy in the diagnostics and treatment of superficial urinary bladder tumors]. / Fluorescencní cystoskopie a její místo v diagnostice a lécbe povrchových nádoru mocového mechýre.

BACKGROUND: 5-aminolevulinic acid induced fluorescence cystoscopy can detect more tumour lesions comparing to standard cystoscopy. The goal of our study was to assess the influence of fluorescence cystoscopy used during transurethral resection on the recurrence rate and the length of tumor-free interval in stage Ta, Tl transitional cell carcinoma of the urinary bladder. METHODS AND RESULTS: In prospective randomized study 109 patients with primary or recurrent stage Ta Tl bladder transitional cell carcinoma treated with transurethral resection were enrolled. 17 patients with high grade tumors were evaluated separately. In group A the transurethral resection was performed with standard white light endoscopy, in group B with fluorescence cystoscopy. The patients were followed using standard cystoscopy and urinary cytology. Recurrence free interval was evaluated in whole groups and also for single and multiple and for primary and recurrent tumors separately. The median time to recurrence was 8.05 months in group A and was significantly shorter than 13.54 months in group B (p = 0.04, log-rank test). In separate analyses the median time to recurrence was significantly shorter using fluorescence cystoscopy in multiple (p = 0.004) and in recurrent (p = 0.02) tumors, but not in solitary and primary tumors. CONCLUSIONS: 5-aminolevulinic acid induced fluorescence cystoscopy used during transurethral resection reduces the early recurrence rate in stage Ta Tl bladder transitional cell carcinoma.

Effect of chloroquine wash-out period of photosensitizers in the skin and selected organs in rats.

In the last decade, photodynamic therapy has become an alternative method for the diagnosis and therapy of tumors. In human medicine hematoporphyrin derivatives, sulfonated hydrophilic meso-tetraphenylporphyrin (TPPS4) and an oligomer of hematoporphyrin (Photosan 3), are widely used. Chloroquine is used for the treatment of porphyria cutanea tarda for its power to release porphyrins from the liver tissue. The kinetics of two porphyrin photosensitizers TPPS4 and Photosan 3 in the skin and some organs as well as the effect of chloroquine on the porphyrin excretion and their accumulation in skin and organs of Wistar rats were studied. TPPS4 exhibited maximum fluorescence in skin 48 h after application with decreasing to basal level from the 8th to the 14th day. Maximum fluorescence was reached at 72 hours after Photosan 3 application and it decreased to basal level during 96 hours after application. TPPS4 caused significantly higher fluorescence compared to Photosan 3. Chloroquine after oral administration did not change the fluorescence of skin, but it significantly decreased the TPPS4 concentration in rat organs if chloroquine treatment started 3 days or 2 weeks after TPPS4 application. Chloroquine significantly decreased the serum TPPS4 concentration during the period of 28 days. Fluorescence of skin was significantly higher and lasted longer after application of TPPS4 compared to Photosan 3. Chloroquine after oral administration did not influence the fluorescence of the skin, but it significantly decreased the TPPS4 concentration in rat organs. This effect could be useful in photodynamic therapy for mobilizing exogenous porphyrins from tissues after parenteral photodynamic therapy.

[Photodynamic diagnosis and therapy in dermatology. Experience with use of TPPS4 in skin diseases]. / Fotodynamická diagnostika a terapie v dermatologii. Zkusenosti s aplikací TPPS4 u nekterých kozních afekcí.

BACKGROUND: Some skin lesions e.g. basal cell carcinomas are sometimes difficult to remove completely and frequent relapses can develop after their imperfect removal. In case the patient refuses to undergo a radical surgical intervention, more painful alternative like cryotherapy comes into consideration as a method of tumour destruction. Not even such a procedure does guarantee complete destruction of all tumour cells. During the last years new diagnostics and therapeutic methods like photodynamic diagnostic and photodynamic therapy have been developed and they became subjects of our interest. METHODS AND RESULTS: Lesions were treated with photosensitizer (meso-tetra-para-sulphonato-phenyl-porfine-TPPS4) administered in an injection or in the ointment under occlusion. Six to 24 hours later we checked presence of photosensitizer in the lesions and in positive cases we irradiated the lesions with light of suitable wave length (630 nm). CONCLUSIONS: PDD and PDT were used for diagnostics and treatment of different dermatoses (basal cell carcinomas, malignant melanoma metastases, verrucae vulgares, keratoacanthomas, solitary lesions of T lymphoma--mycosis fungoides, m. Bowen, psoriasis vulgaris, pustulosis palmoplantaris, solar keratoma) with very good medical and cosmetic effect. Results are presented in the table. Authors do not consider the PDT to be the only and miraculous method relevant to treatment of all skin tumours or other skin diseases. They are of the opinion that this technique, when properly used, can extend the scale of therapeutic methods. The advantage of PDT is its selectivity, good tolerance and generally good cosmetic effect.

[CEACAM1--a less well-known member of the family of carcinoembryonic antigens]. / CEACAM1--méne známý clen rodiny karcinoembryonálního antigenu.

CEACAM1 (carcinoembryonic antigen-related cell adhesion molecule 1) is a transmembrane glycoprotein belonging to the carcinoembryonic antigen (CEA) family and immunoglobulin superfamily. It is localized mainly in the apical domains of polarized epithelia, leukocytes and endothelia. With respect to this wide tissue distribution the research is focused on the study of its biological functions. Structural and functional analyses show that the extracellular domain of CEACAM1 participates in homotypic and heterotypic adhesion, whereas the cytoplasmic domain takes part in cell growth inhibition and signal transduction. Whereas CEA is highly expressed in adenocarcinomas, CEACAM1 expression is down regulated in many tumors and its tumor-supressive function was confirmed. CEACAM1 also takes part in insulin metabolism, acts as a promotor of cholesterol crystallization and serves as a binding receptor for certain bacterial strains in humans as well as hepatitis virus in mice.

[Fluorescence cystoscopy using 5-aminolevulinic acid]. / Fluorescencní cystoskopie za pouzití 5-aminolevulové kyseliny.

BACKGROUND: Fluorescence diagnosis has an increasing importance in different medical fields. In the presented paper, comparison of cystoscopy in white light with fluorescence cystoscopy after intravesical administration of 1 g of 5-aminolevulinic acid is presented. METHODS AND RESULTS: From the group of 63 persons examined, no difference between findings in white and blue light was found in 39 cases. In 21 patients more pathological spots were found in blue light (10 cases) or, in agreement with histology, pathology was detected in the blue light only (11 cases). CONCLUSIONS: The intravesical administration of 5-aminolevulinic acid had no side effects. Our study has definitely proved the advantages of fluorescence cystoscopy.

Effect of acute hyperglycaemia on selected plasma and urinary cytokine antagonists in Type 1 diabetes mellitus.

AIMS/HYPOTHESIS: Several cytokines have been implicated in the pathogenesis of diabetic nephropathy. Their ability to generate a biological response in vivo is modulated by specific antagonists and soluble receptors. The aims of the study were firstly, to measure the interleukin 1 receptor antagonist (IL-1ra) and tumour necrosis factor alpha soluble receptors p55 (TNFsr1) and p75 (TNFsr2) in plasma and urine, and secondly to test their response to acutely induced hyperglycaemia in Type 1 diabetes mellitus (DM 1). METHODS: Plasma concentrations and urinary excretions of IL-1ra, TNFsr1 and TNFsr2 were measured in two 90-min periods of glycaemic clamp-induced normoglycaemia and hyperglycaemia (5 and 12 mmol/l; study 1) and during time-controlled normoglycaemia (5 and 5 mmol/l; study 2) in 20 Type 1 diabetic patients with normal albumin excretion and normal glomerular filtration rate, and in 11 weight-, age- and sex-matched healthy control subjects. RESULTS: The plasma concentrations of IL-1ra, TNFsr1 and TNFsr2 were comparable in Type 1 diabetic patients and control subjects, and no significant changes during study 1 and study 2 were found. Urinary IL-1ra excretion measured during normoglycaemia was higher in Type 1 diabetic patients compared to control subjects ( p<0.05). In diabetic patients, it decreased in study 1 compared to study 2 ( p<0.05), while it did not change in control subjects. The urinary excretions of TNFsr1 and TNFsr2 during normoglycaemia were comparable in diabetic patients and controls. In diabetic patients, hyperglycaemia decreased TNFsr1 excretion (study 1 vs study 2; p<0.01), while TNFsr1 excretion did not change in control subjects. Hyperglycaemia did not affect TNFsr2 excretion in diabetic patients, while it led to an increase in TNFsr2 excretion in control subjects (study 1 vs study 2; p<0.05). Despite comparable renal haemodynamics, diabetic patients had lower fractional excretion of sodium compared to control subjects ( p<0.01). No significant relationships between cytokine antagonists and renal functions have been found. CONCLUSION/INTERPRETATION: Type 1 diabetic patients with normal renal haemodynamics are associated with impaired regulation of renal IL-1ra, TNFsr1 and TNFsr2 production with a potential impact on local control of cytokine activity in the kidneys.

New type of vortex pinning structure effective at very high magnetic fields.

We report on a new type of correlated nanometer-scale pinning structure observed in a melt-processed (Nd0.33Eu0.38Gd0.28)Ba(2)Cu(3)O(y) (NEG-123). It consists of NEG/Ba-rich clusters in the stoichiometric NEG-123 matrix forming a lamellar array with a period of a few nanometers. These lamellas appear within regular twins, thus representing their fine substructure-sometimes straight, sometimes wavy. This new material structure correlates well with the significant enhancement of pinning at high fields, represented by irreversibility field above 14 T at 77 K (B parallel c). We believe that the new pinning medium enables one to significantly broaden the limits for high-field applications.