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101.

Background

This study evaluates the surgical morbidity and long-term outcome of colorectal cancer surgery in an unselected group of patients treated over the period 1994–2003.

Methods

A consecutive series of 902 primary colorectal cancer patients (489 M, 413 F; mean age: 63 years ± 11 years, range: 24–88 years) was evaluated and prospectively followed in a university hospital (mean follow-up 36 ± 24 months; range: 3–108 months). Perioperative mortality, morbidity, overall survival, curative resection rates, recurrence rates were analysed.

Results

Of the total, 476 colorectal cancers were localized to the colon (CC, 53%), 406 to the rectum (RC, 45%), 12 (1%) were multicentric, and 8 were identified as part of HNPCC (1%). Combining all tumours, there were 186 cancers (20.6%) defined as UICC stage I, 235 (26.1%) stage II, 270 (29.9%) stage III and 187 (20.6%) stage IV cases. Twenty-four (2.7%) cases were of undetermined stage. Postoperative complications occurred in 38% of the total group (37.8% of CC cases, 37.2% of the RC group, 66.7% of the synchronous cancer patients and 50% of those with HNPCC, p = 0.19) Mortality rate was 0.8%, (1.3% for colon cancer, 0% for rectal cancer; p = 0.023). Multivisceral resection was performed in 14.3% of cases. Disease-free survival in cases resected for cure was 73% at 5-years and 72% at 8 years. The 5- and 8-year overall survival rates were 71% and 61% respectively (total cases). At 5-year analysis, overall survival rates are 97% for stage I disease, 87% for stage II, 73% for stage III and 22% for stage IV respectively (p < 0.0001). The 5-year overall survival rates showed a marked difference in R0, R1+R2 and non resected patients (82%, 35% and 0% respectively, p < 0.0001). On multivariate analysis, resection for cure and stage at presentation but not tumour site (colon vs. rectum) were independent variables for overall survival (p < 0.0001).

Conclusion

A prospective, uniform follow-up policy used in a single institution over the last decade provides evidence of quality assurance in colorectal cancer surgery with high rates of resection for cure where only stage at presentation functions as an independent variable for cancer-related outcome.  相似文献   
102.
103.
Multiple myeloma (MM) is the paradigmatic proteasome inhibitor (PI) responsive cancer, but many patients fail to respond. An attractive target to enhance sensitivity is (macro)autophagy, recently found essential to bone marrow plasma cells, the normal counterpart of MM. Here, integrating proteomics with hypothesis-driven strategies, we identified the autophagic cargo receptor and adapter protein, SQSTM1/p62 as an essential component of an autophagic reserve that not only synergizes with the proteasome to maintain proteostasis, but also mediates a plastic adaptive response to PIs, and faithfully reports on inherent PI sensitivity. Lentiviral engineering revealed that SQSTM1 is essential for MM cell survival and affords specific PI protection. Under basal conditions, SQSTM1-dependent autophagy alleviates the degradative burden on the proteasome by constitutively disposing of substantial amounts of ubiquitinated proteins. Indeed, its inhibition or stimulation greatly sensitized to, or protected from, PI-induced protein aggregation and cell death. Moreover, under proteasome stress, myeloma cells selectively enhanced SQSTM1 de novo expression and reset its vast endogenous interactome, diverting SQSTM1 from signaling partners to maximize its association with ubiquitinated proteins. Saturation of such autophagic reserve, as indicated by intracellular accumulation of undigested SQSTM1-positive aggregates, specifically discriminated patient-derived myelomas inherently susceptible to PIs from primarily resistant ones. These aggregates correlated with accumulation of the endoplasmic reticulum, which comparative proteomics identified as the main cell compartment targeted by autophagy in MM. Altogether, the data integrate autophagy into our previously established proteasome load-versus-capacity model, and reveal SQSTM1 aggregation as a faithful marker of defective proteostasis, defining a novel prognostic and therapeutic framework for MM.  相似文献   
104.
The parasitic protists in the genus Tritrichomonas cause significant disease in domestic cattle and cats. To assess the genetic diversity of feline and bovine isolates of Tritrichomonas foetus (Riedmüller, 1928) Wenrich and Emmerson, 1933, we used 10 different genetic regions, namely the protein coding genes of cysteine proteases 1, 2 and 4–9 (CP1, 2, 4–9) involved in the pathogenesis of the disease caused by the parasite. The cytosolic malate dehydrogenase 1 (MDH1) and internal transcribed spacer region 2 of the rDNA unit (ITS2) were included as additional markers. The gene sequences were compared with those of Tritrichomonas suis (Davaine, 1875) Morgan and Hawkins, 1948 and Tritrichomonas mobilensis Culberson et al., 1986. The study revealed 100% identity for all 10 genes among all feline isolates (=T. foetus cat genotype), 100% identity among all bovine isolates (=T. foetus cattle genotype) and a genetic distinctness of 1% between the cat and cattle genotypes of T. foetus. The cattle genotype of T. foetus was 100% identical to T. suis at nine loci (CP1, 2, 4–8, ITS2, MDH1). At CP9, three out of four T. suis isolates were identical to the T. foetus cattle genotype, while the T. suis isolate SUI-H3B sequence contained a single unique nucleotide substitution. Tritrichomonas mobilensis was 0.4% and 0.7% distinct from the cat and cattle genotypes of T. foetus, respectively. The genetic differences resulted in amino acid changes in the CP genes, most pronouncedly in CP2, potentially providing a platform for elucidation of genotype-specific host-pathogen interactions of T. foetus. On the basis of this data we judge T. suis and T. foetus to be subjective synonyms. For the first time, on objective nomenclatural grounds, the authority of T. suis is given to Davaine, 1875, rather than the commonly cited Gruby and Delafond, 1843. To maintain prevailing usage of T. foetus, we are suppressing the senior synomym T. suis Davaine, 1875 according to Article 23.9, because it has never been used as a valid name after 1899 and T. foetus is widely discussed as the cause of bovine trichomonosis. Thus bovine, feline and porcine isolates should all be given the name T. foetus. This promotes the stability of T. foetus for the veterinary and economically significant venereal parasite causing bovine trichomonosis.  相似文献   
105.
The leader gene approach is a data mining method based on the systematic search for genes involved in a specific process and their ranking according to the number of interconnections with the other genes identified. The genes with the strongest interconnections are termed leader genes, since they may be supposed to play an important role in the process. The potential of malignant progression of OLP to oral squamous cell carcinoma (OSCC) is still not completely clear. In this study, the leader gene approach is applied to investigate the association between OLP and OSCC at a molecular level. Results were integrated with those obtained in an experimental analysis (see paper 1 of this series). Genes involved in OLP and OSCC were identified by systematic queries to dedicated databases. Interconnections among identified genes were calculated and given a confidence value using STRING database. Leader genes were identified by clustering genes according to their interconnections. This theoretical analysis shows that OLP and OSCC share two leader genes: TP53 and CDKN1A, involved in the PI3K signalling events mediated by AKT pathway. This finding and those obtained in the experimental analysis suggest the possible involvement of some key genes/proteins LCK, PIK3CA, BIRC5, TP53 and CDKN1A in the malignant progression from OLP to OSCC. Moreover, these findings support the role of some molecular pathways, namely IL2 signalling events mediated by PI3K, PI3K signalling events mediated by AKT, and, possibly, Aurora A signalling in the association between OLP and OSCC.  相似文献   
106.
Obligate psychrophilic, facultative psychrophilic, and mesophilic yeasts were cultured in a carbon-rich medium at different temperatures to investigate whether growth parameters, lipid accumulation, and fatty acid (FA) composition were adaptive and/or acclimatory responses. Acclimation of facultative psychrophiles and mesophiles to a lower temperature decreased their specific growth rate, but did not affect their biomass yield (YX/S). Obligate and facultative psychrophiles exhibited the highest YX/S. Acclimation to lower temperature decreased the lipid yield (YL/X) in mesophilic yeasts, but did not affect YL/X in facultative psychrophilic ones. Similar YL/X were found in both groups of psychrophiles, suggesting that lipid accumulation is not a distinctive characteristic of adaptation to permanently cold environments. The unsaturation of FAs was one major adaptive feature of the yeasts colonizing permanently cold ecosystems. Remarkable amounts of α-linolenic acid were found in obligate psychrophiles at the expense of linoleic acid, whereas it was scarce or absent in all the other strains. Increased unsaturation of FAs was also a general acclimatory response of facultative psychrophiles to a lower temperature. These results improve the knowledge of the responses enabling psychrophilic yeasts to cope with the cold and may be of support for potential biotechnological exploitation of these strains.  相似文献   
107.
108.
There are extensive data indicating that some glacial refuge zones of southern Europe (Franco-Cantabria, Balkans, and Ukraine) were major genetic sources for the human recolonization of the continent at the beginning of the Holocene. Intriguingly, there is no genetic evidence that the refuge area located in the Italian Peninsula contributed to this process. Here we show, through phylogeographic analyses of mitochondrial DNA (mtDNA) variation performed at the highest level of molecular resolution (52 entire mitochondrial genomes), that the most likely homeland for U5b3—a haplogroup present at a very low frequency across Europe—was the Italian Peninsula. In contrast to mtDNA haplogroups that expanded from other refugia, the Holocene expansion of haplogroup U5b3 toward the North was restricted by the Alps and occurred only along the Mediterranean coasts, mainly toward nearby Provence (southern France). From there, ∼7,000–9,000 years ago, a subclade of this haplogroup moved to Sardinia, possibly as a result of the obsidian trade that linked the two regions, leaving a distinctive signature in the modern people of the island. This scenario strikingly matches the age, distribution, and postulated geographic source of a Sardinian Y chromosome haplogroup (I2a2-M26), a paradigmatic case in the European context of a founder event marking both female and male lineages.  相似文献   
109.
Resistance against synthetic pyrethroid (SP) products for the control of cattle ticks in Australia was detected in the field in 1984, within a very short time of commercial introduction. We have identified a mutation in the domain II S4-5 linker of the para-sodium channel that is associated with resistance to SPs in the cattle tick Rhipicephalus (Boophilus) microplus from Australia. The cytosine to adenine mutation at position 190 in the R. microplus sequence AF134216, results in an amino acid substitution from leucine in the susceptible strain to isoleucine in the resistant strain. A similar mutation has been shown to confer SP resistance in the whitefly, Bemisia tabaci, but has not been described previously in ticks. A diagnostic quantitative PCR assay has been developed using allele-specific Taqman® minor groove-binding (MGB) probes. Using the assay to screen field and laboratory populations of ticks showed that homozygote allelic frequencies correlated highly with the survival percentage at the discriminating concentration of cypermethrin.  相似文献   
110.
Background  The vast majority of non-human primates used for experimental activities are purpose-bred. However, in case of particular procedures or specific projects, it may still be necessary to use animals captured in the wild.
Methods  Sixty cynomolgus monkeys were randomly selected on the basis of breeding origin, and assigned to two groups, each of fifteen males and fifteen females. Analyses included the most frequently investigated parameters for hematology, coagulation, and biochemistry.
Results  Differences were observed in some parameters, particularly in eosinophils, basophils and monocytes, and in fibrinogen, total protein, globulins, alanine amino-transferase, creatinine, aspartate amino-transferase, alkaline phosphatase, γ-glutamyl transferase, lactate dehydrogenase, α-hydroxybutyrate dehydrogenase, iron, potassium, and phosphorus.
Conclusions  Some values in the cynomolgus monkey may show significant differences according to the breeding background of the animals. Only data obtained from animals of similar origin have to be compared, to avoid misinterpretation during the evaluation of the experimental results.  相似文献   
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