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1.

Background

In the spectrum of molecular alterations found in hepatocellular carcinoma (HCC), somatic mutations in the WNT/β-catenin pathway and the p53/cell cycle control pathway are among the most frequent ones. It has been suggested that both mutations occur in a mutually exclusive manner and they are used as molecular classifiers in HCC classification proposals.

Case presentation

Here, we report the case of a treatment-naïve mixed hepatocellular/cholangiocellular carcinoma (HCC/CCC) with morphological and genetic intratumor heterogeneity. Within the predominant part of the tumor with hepatocellular differentiation, a p.D32V mutation in exon 3 of the CTNNB1 gene occurred concomitantly with a TP53 intron 7/exon 8 splice site mutation.

Conclusion

Intratumor heterogeneity challenges the concept of CTNNB1 and TP53 gene mutations being mutually exclusive molecular classifiers in HCC, which has implications for HCC classification approaches.
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Galba truncatula snails were experimentally infected with either of two different isolates of Fasciola gigantica, originating from Egypt or China, to determine the influence of these isolates on the characteristics of snail infections. The survival rates of G. truncatula on day 30 post-exposure were 90.0% and 60.2% in the Egyptian and Chinese groups, respectively. The frequency of cercaria-shedding snails within the Egyptian group was 79.8%, whereas in the Chinese group it was 22.4%. The parasite origin had a significant effect on the durations of the prepatent and patent periods. The mean number of cercariae shed from the Egyptian group was significantly greater than that shed from the Chinese group (a mean of 275.5 per cercaria-shedding snail compared with 29.0). These results could be explained by the fact that G. truncatula might be a natural intermediate host for F. gigantica in Egypt, and the greater adaptability of the Egyptian miracidia of F. gigantica to unusual snail hosts. These results demonstrate the influence of the geographic origin of the parasite on the success of trematodes infecting snails.  相似文献   

5.
In Europe, Serbia ranks among countries with a high prevalence of Trichinella infection in pigs, which continues to be a serious human health problem. While in some Balkan countries, more than one Trichinella species/genotype has been described in both the sylvatic and domestic cycles, these data are lacking for Serbia. To date, only a few Serbian isolates of Trichinella have been genetically specified, and all were classified as T. spiralis. Although transmission of Trichinella from domestic pigs to wildlife could be assumed, neither the infection status nor the species of Trichinella circulating among wildlife in Serbia has been investigated. This study shows the presence of two Trichinella species, T. spiralis and T. britovi, in wild animals originating from five districts in Serbia, where Trichinella infections in domestic pigs and humans have been recorded. Trichinella spiralis was detected in jackals (n = 3), red foxes (n = 2) and a wild cat (n = 1). We also established that wolves (n = 4) and red foxes (n = 2) serve as sylvatic reservoirs for T. britovi. This is the first report on the presence of T. britovi in Serbia.  相似文献   

6.
Obeliscoides cuniculi is a New World nematode parasite of the Trichostrongilidae family infecting the gastric tract of different domestic and wild Lagomorph species. This parasite is reported for the first time from a European brown hare (Lepus europaeus). The nematodes isolated from the gastro-intestinal tract were identified using the primary characteristics used to differentiate the species of this genus as adults morphology (length and thickness) and other characteristics of spicules, cervical papillae, cuticular ridges and striations. In the Italian study area, the European brown hare lives in sympatry with the eastern cottontail (Sylvilagus floridanus), species in which the nematode was previously isolated; therefore, the possibility of a cross-infestation must be considered.  相似文献   

7.
Leishmania (Viannia) braziliensis is the major causative agent of American tegumentary leishmaniasis, a disease that has a wide geographical distribution and is a severe public health problem. The cysteine proteinase B (CPB) from Leishmania spp. represents an important virulence factor. In this study, we characterized and localized cysteine proteinases in L. (V.) braziliensis promastigotes. By a combination of triton X-114 extraction, concanavalin A-affinity, and ion exchange chromatographies, we obtained an enriched fraction of hydrophobic proteins rich in mannose residues. This fraction contained two proteinases of 63 and 43 kDa, which were recognized by a CPB antiserum, and were partially sensitive to E-64 in enzymatic assays with the peptide Glu-Phe-Leu. In confocal microscopy, the CPB homologues localized in the peripheral region of the parasite. This data together with direct agglutination and flow cytometry assays suggest a surface localization of the CPB homologues. The incubation of intact promastigotes with phospholipase C reduced the number of CPB-positive cells, while anti-cross-reacting determinant and anti-CPB antisera recognized two polypeptides (63 and 43 kDa) derived from phospholipase C treatment, suggesting that some CPB isoforms may be glycosylphosphatidylinositol-anchored. Collectively, our results suggest the presence of CPB homologues in L. braziliensis surface and highlight the need for further studies on L. braziliensis cysteine proteinases, which require enrichment methods for enzymatic detection.  相似文献   

8.
Serrated neoplasm of the colorectum raised many as-yet unanswered issues. To characterize serrated neoplasia pathway, we investigated BRAF and KRAS mutations in 35 traditional serrated adenomas. BRAF exons 11 and 15, and KRAS exon 2 were amplified by polymerase chain reaction and directly sequenced. BRAF V599E mutation was found in 27 serrated adenomas (77.1%), and KRAS mutations were found in 3 (8.6%) of 35 traditional serrated adenomas. In 13 cases, mixed polyps composed of traditional serrated adenomas and hyperplastic (serrated) polyps were observed, and seven of them showed the same BRAF mutations in both components. Somatic mutations of BRAF and KRAS genes were mutually exclusive. These findings suggest that BRAF mutations are early and a critical event in the serrated adenomas, and most serrated adenomas in both sides of colon may progress from microvesicular hyperplastic polyps via BRAF mutations, and some left-sided serrated adenomas develop via KRAS mutations.  相似文献   

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Environmental concerns over the cultivation of Genetically Modified (GM) crops largely centre on the ecological consequences following gene flow to wild relatives. One attractive solution is to deploy biocontainment measures that prevent hybridization. Chloroplast transformation is the most advanced biocontainment method but is compromised by chloroplast capture (hybridization through the maternal lineage). To date, however, there is a paucity of information on the frequency of chloroplast capture in the wild. Oilseed rape (Brassica napus, AACC) frequently hybridises with wild Brassica rapa (AA, as paternal parent) and yields B. rapa-like introgressed individuals after only two generations. In this study we used chloroplast CAPS markers that differentiate between the two species to survey wild and weedy populations of B. rapa for the capture of B. napus chloroplasts. A total of 464 B. rapa plants belonging to 14 populations growing either in close proximity to B. napus (i.e. sympatric <5 m) or else were allopatric from the crop (>1 km) were assessed for chloroplast capture using PCR (trnL-F) and CAPS (trnT-L-Xba I) markers. The screen revealed that two sympatric B. rapa populations included 53 plants that possessed the chloroplast of B. napus. In order to discount these B. rapa plants as F1 crop-wild hybrids, we used a C-genome-specific marker and found that 45 out of 53 plants lacked the C-genome and so were at least second generation introgressants. The most plausible explanation is that these individuals represent multiple cases of chloroplast capture following introgressive hybridisation through the female germ line from the crop. The abundance of such plants in sympatric sites thereby questions whether the use of chloroplast transformation would provide a sufficient biocontainment for GM oilseed rape in the United Kingdom.  相似文献   

10.
Pseudomonas aeruginosa is an opportunistic pathogen of immunocompromised hosts. In cystic fibrosis (CF), P. aeruginosa causes acute and chronic lung infections that result in significant morbidity and mortality. P. aeruginosa possesses several traits that contribute to its ability to colonize and persist in acute and chronic infections. These include high resistance to antimicrobials, ability to form biofilms, plethora of virulence products, and metabolic versatility. In P. aeruginosa, a cell-to-cell communication process termed quorum sensing (QS) regulates many of these factors that contribute to its pathogenesis. Recent evidence suggests that the CF lung environment presents a specialized niche for P. aeruginosa. The relationship of P. aeruginosa QS, biofilm formation, and the CF lung environment is discussed.  相似文献   

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Lemuricola (Madoxyuris) bauchoti Chabaud, Brygoo et Petter, 1965 is redescribed from material collected from the ring-tailed lemur, Lemur catta, from the Beza Mahafaly Special Reserve in Madagascar using the scanning electron microscope. This is a new host record and the first oxyurid reported from the ring-tailed lemur. Previously, records of each species of the subgenus Madoxyuris have been restricted to a single host species, but the close relationship between these nematodes and their Strepsirrhini hosts will only be proven when additional records fill in the gaps in their distribution.  相似文献   

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The notion that coronary atherosclerosis and its most severe phenotype, myocardial infarction (MI), are chronic inflammatory diseases is supported by several lines of evidence. Interleukins (ILs) are important mediators and modulators of inflammation. Specific polymorphisms in the genes encoding subunits of IL-23 (IL-12B) and its receptor (IL-23R) have recently been consistently found to be associated with chronic immune-mediated diseases. In this study, we explored the hypothesis that these variants also affect the risk of MI. We conducted a case-control association study on a cohort of 738 British Caucasian MI patients and 716 population controls. We tested four variants (rs11209026, rs7517847, rs1343151, rs10889677) of IL-23R and the A1188C polymorphism (rs3212227) of IL-12B. There was no association of any IL-23R (rs11209026, p = 0.82; rs7517847, p = 0.87; rs1343151, p = 0.85; rs10889677, p = 0.48) or IL-12B (rs3212227, p = 0.32) polymorphisms with MI. Stratification for age, gender and other cardiovascular risk factors did not affect the findings. These results indicate that unlike other chronic inflammatory diseases, the examined variants are unlikely to be major contributors to the pathogenesis of MI.  相似文献   

13.

Objective  

The present study was designed to investigate the role of X-ray cross-complementing group 1 (XRCC1) and apurinic/apyrimidinic endonuclease 1 (APE1) polymorphisms in apoptosis and the risk of ulcerative colitis (UC).  相似文献   

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A 14-year-old boy who was neutropenic following chemotherapy for leukemia developed fungemia caused by the yeast Kodomaea ohmeri (Pichia ohmeri). The infection was cured by catheter removal and the use of fluconazole. A 74-year-old man who had undergone surgeries for a subcutaneous tumor developed polymicrobic cellulitis involving Kodomaea ohmeri. Despite surgical debridement and antibiotic therapy, the patient died of complications. Including these 2 cases, there have been 10 Kodomaea ohmeri infections reported thus far, all occurring in patients with pre-existing conditions. There have been seven cases of fungemia and one case each of peritonitis, funguria, and cellulitis. The treatment employed varied depending on the site/source of infection. Seven patients recovered and three died. The microbiological data available suggest that Kodomaea ohmeri can be identified definitively by biochemical tests and is susceptible to amphotericin B and either susceptible to or dose dependently susceptible to itraconazole and fluconazole.  相似文献   

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Genomic in-situ hybridization (GISH) was applied to study the behaviour of addition chromosomes in first and second backcross (BC) progenies of hybrids between Brassica napus ssp. napus L. (AACC, 2n = 38) and Sinapis alba L. (SS, 2n = 24) produced by electrofusion. With GISH using genomic DNA of S. alba was used as probe it was possible to clearly distinguish both of the parental genomes and effectively monitor the fate of S. alba chromosomes in the BC1 and BC2 progenies. GISH analysis confirmed the sesquidiploid genome composition (AACCS) of the BC1 progenies, which contained 38 chromosomes from B. napus and 12 chromosomes from S. alba. Genome painting in the pollen mother cells (PMCs) of the BC1 plants revealed intergenomic association between B. napus and S. alba chromosomes, whereby a maximum of 4 trivalents between AC and S chromosomes were identified at metaphase I. In the BC2 progenies, aneuploids with different numbers of additional chromosomes from S. alba, ranging from 1 to 7, were confirmed. Three putative monosomic alien addition lines were characterized, and the results are discussed with respect to the potential for intergenomic chromosome recombination.  相似文献   

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The deletion of thiazide-sensitive Na–Cl cotransporter (TSC, SLC12A3) causes Gitelmans syndrome characterized by low blood pressure, while deletions of the WNK1 (PRKWNK1) and WNK4 (PRKWNK4) genes cause familial hypertension known as pseudohypoaldosteronism type II. Recent studies have revealed that cell surface expression of TSC is regulated by WNK1 and WNK4. We hypothesized that molecular variations in TSC, WNK1, and WNK4 could lead to an increased morbidity of hypertension. We identified 52, 35, and 21 polymorphisms in Japanese hypertensives by sequencing the entire coding regions of TSC, WNK1 and WNK4, respectively. Twenty-one representative polymorphisms were genotyped in 1,818 Japanese individuals (771 subjects with hypertension and 1,047 controls) randomly sampled in Suita city. The results indicated that the systolic blood pressure in men with the CT+TT genotype in WNK4 C14717T was 3.1 mmHg higher than those with the CC genotype (p=0.042) after adjustment with confounding factors such as age, BMI, hyperlipidemia, diabetes mellitus, antihypertensive drug use, smoking, and drinking. Multivariate logistic regression analysis (with adjustment for the same parameters) in men revealed that the odds ratio for the presence of hypertension of the CT+TT genotype in C14717T to the CC genotype was 1.62 (p=0.010, 95% confidence interval, 1.12–2.33). Association of TSC and WNK1 with hypertension was not observed. In conclusion, our study suggests the possible involvement of WNK4 in essential hypertension in a Japanese general population.  相似文献   

20.

Background  

The current treatment of onchocerciasis relies on the use of ivermectin which is only microfilaricidal and for which resistant parasite strains of veterinary importance are increasingly being detected. In the search for novel filaricides and alternative medicines, we investigated the selective activity of crude extracts of Margaritaria discoidea and Homalium africanum on Onchocerca ochengi, a model parasite for O. volvulus. These plants are used to treat the disease in North West Cameroon.  相似文献   

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