For the extended skew-normal distribution, which represents an extension of the normal (or Gaussian) distribution, we focus on the properties of the log-likelihood function and derived quantities in ...the the bivariate case. Specifically, we derive explicit expressions for the score function and the information matrix, in the observed and the expected form; these do not appear to have been examined before in the literature. Corresponding computing code in R language is provided, which implements the formal expressions.
The power of modelization in physics and in engineering is not in doubt, while in the biotechnological field many theoretical studies stop at the description level. It is time for theoretical ...modelization to enter the field of biotechnology, and that needs people with both physical and biological knowledge.This book introduces interested scientists with varied backgrounds to active research in different areas broadly related to what has come to be called "dynamical modeling in biology".
Inflammation and coagulation constantly influence each other and are constantly in balance. Emerging evidence supports this statement in acute inflammatory diseases, such as sepsis, but it also seems ...to be very important in chronic inflammatory settings, such as inflammatory bowel disease （IBD）. Patients with Crohn＇s disease and ulcerative colitis have an increased risk of thromboembolic events, and several abnormalities concerning coagulation components occur in the endothelial cells of intestinal vessels, where most severe inflammatory ab- normalities occur. The aims of this review are to update and classify the type of coagulation system abnormalities in IBD, and analyze the strict and delicate balance between coagulation and inflammation at the mucosal level. Recent studies on possible therapeutic applications arising from investigations on coagulation abnormalities associated with IBD pathogenesis will also be briefly presented and critically reviewed.
Glutathione S-Transferase enzymes (GSTs) constitute the principal Phase II superfamily which plays a key role in cellular detoxification and in other biological processes. Studies of GSTs have ...revealed that genetic polymorphisms are present in these enzymes and that some of these are Loss-of-Function (LoF) variants, which affect enzymatic functions and are related to different aspects of human health.
The aim of this study was to analyze functional genetic differences in GST enzymes among human populations. Attention was focused on LoF polymorphisms of GSTA1, GSTM1, GSTO1, GSTO2, GSTP1 and GSTT1 genes. These LoF variants were analyzed in 668 individuals belonging to six human groups with different ethnic backgrounds: Amhara and Oromo from Ethiopia; Colorado and Cayapa Amerindians and African Ecuadorians from Ecuador; and one sample from central Italy. The HapMap database was used to compare our data with reference populations and to analyze the haplotype and Linkage Disequilibrium diversity in different ethnic groups.
Our results highlighted that ethnicity strongly affects the genetic variability of GST enzymes. In particular, GST haplotypes/variants with functional impact showed significant differences in human populations, according to their ethnic background. These data underline that human populations have different structures in detoxification genes, suggesting that these ethnic differences influence disease risk or response to drugs and therefore have implications for genetic association studies involving GST enzymes.
In conclusion, our investigation provides data about the distribution of important LoF variants in GST genes in human populations. This information may be useful for designing and interpreting genetic association studies.
► Functional genetic differences in GST enzymes among human populations were analyzed. ► Ethnicity strongly affects the genetic variability of GST enzymes. ► Functional GST variants showed differences according to the population origin. ► These ethnic differences may influence disease risk or response to drugs.
Radical gastrectomy with an adequate lymph-adenectomy is the main procedure which makes it possible to cure patients with resectable gastric cancer(GC). A number of randomized controlled trials and ...meta-analysis provide phase Ⅲ evidence that laparoscopic gastrectomy is technically safe and that it yields better short-term outcomes than conventional open gastrectomy for early-stage GC. While laparoscopic gastrectomy has become standard therapy for early-stage GC, especially in Asian countries such as Japan and South Korea, the use of minimally invasive techniques is still controversial for the treatment of more advanced tumours, principally due to existing concerns about its oncological adequacy and capacity to carry out an adequately extended lymphadenectomy. Some intrinsic drawbacks of the conventional laparoscopic technique have prevented the worldwide spread of laparoscopic gastrectomyfor cancer and, despite technological advances in recent year, it remains a technically challenging procedure. The introduction of robotic surgery over the last ten years has implied a notable mutation of certain minimally invasive procedures, making it possible to overcome some limitations of the traditional laparoscopic technique. Robot-assisted gastric resection with D2 lymph node dissection has been shown to be safe and feasible in prospective and retrospective studies. However, to date there are no high quality comparative studies investigating the advantages of a robotic approach to GC over traditional laparoscopic and open gastrectomy. On the basis of the literature review here presented, robot-assisted surgery seems to fulfill oncologic criteria for D2 dissection and has a comparable oncologic outcome to traditional laparoscopic and open procedure. Robot-assisted gastrectomy was associated with the trend toward a shorter hospital stay with a comparable morbidity of conventional laparoscopic and open gastrectomy, but randomized clinical trials and longer follow-ups are needed to evaluate the possible influence of robot gastrectomy on GC patient survival.
Effects of some methodological factors on in vitro measures of gas production（GP, mL/g DM）, CH4production（mL/g DM） and proportion（% CH4 on total GP） were investigated by meta-analysis. These factors ...were considered：pressure in the GP equipment（0 = constant; 1 = increasing）, incubation time（0 = 24; 1 = ≥ 48 h）, time of rumen fluid collection（0 = before feeding; 1 = after feeding of donor animals）, donor species of rumen fluid（0 = sheep; 1 =bovine）, presence of N in the buffer solution（0 = presence; 1 = absence）, and ratio between amount of buffered rumen fluid and feed sample（BRF/FS; 0 = ≤ 130 mL/g DM; 1 = 130–140 mL/g DM; 2 = ≥ 140 mL/g DM）. The NDF content of feed sample incubated（NDF） was considered as a continuous variable. From an initial database of 105 papers, 58 were discarded because one of the above-mentioned factors was not stated. After discarding 17 papers,the final dataset comprised 30 papers（339 observations）. A preliminary mixed model analysis was carried out on experimental data considering the study as random factor. Variables adjusted for study effect were analyzed using a backward stepwise analysis including the above-mentioned variables. The analysis showed that the extension of incubation time and reduction of NDF increased GP and CH4 values. Values of GP and CH4 also increased when rumen fluid was collected after feeding compared to before feeding（＋26.4 and ＋9.0 mL/g DM, for GP and CH4）,from bovine compared to sheep（＋32.8 and ＋5.2 mL/g DM, for GP and CH4）, and when the buffer solution did not contain N（＋24.7 and ＋6.7 mL/g DM for GP and CH4）. The increase of BRF/FS ratio enhanced GP and CH4production（＋7.7 and ＋3.3 mL/g DM per each class of increase, respectively）. In vitro techniques for measuring GP and CH4 production are mostly used as screening methods, thus a full standardization of such techniques is not feasible. However, a greater harmonization of analytical procedures（i.e., a reduction in the number of available protocols） would be useful to facilitate comparison between results of different experiments.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Keratin 8 (KRT8) is one of the major intermediate filament proteins expressed in single-layered epithelia of the gastrointestinal tract. Transgenic mice over-expressing human KRT8 display pancreatic ...mononuclear infiltration, interstitial fibrosis and dysplasia of acinar cells resulting in exocrine pancreatic insufficiency. These experimental data are in accordance with a recent report describing an association between KRT8 variations and chronic pancreatitis. This prompted us to investigate KRT8 polymorphisms in patients with pancreatic disorders. The KRT8 Y54H and G62C polymorphisms were assessed in a cohort of patients with acute and chronic pancreatitis of various aetiologies or pancreatic cancer originating from Austria (n=16), the Czech Republic (n=90), Germany (n=1698), Great Britain (n=36), India (n=60), Italy (n=143), the Netherlands (n=128), Romania (n=3), Spain (n=133), and Switzerland (n=129). We also studied 4,234 control subjects from these countries and 1,492 control subjects originating from Benin, Cameroon, Ethiopia, Ecuador, and Turkey. Polymorphisms were analysed by melting curve analysis with fluorescence resonance energy transfer probes. The frequency of G62C did not differ between patients with acute or chronic pancreatitis, pancreatic adenocarcinoma and control individuals. The frequency of G62C varied in European populations from 0.4 to 3.8%, showing a northwest to southeast decline. The Y54H alteration was not detected in any of the 2,436 patients. Only 3/4,580 (0.07%) European, Turkish and Indian control subjects were heterozygous for Y54H in contrast to 34/951 (3.6%) control subjects of African descent. Our data suggest that the KRT8 alterations, Y54H and G62C, do not predispose patients to the development of pancreatitis or pancreatic cancer.
An electronic nose system, which employs an array of inexpensive commercial tin oxide odour sensors, has been used to analyse the ripeness of bananas. Readings were taken from the headspace of three ...sets of bananas during ripening over a period of 8-14 days. A principal components analysis and investigatory techniques were used to define seven distinct regions in multisensor space according to the state of ripeness of the bananas, predicted from a classification of banana skin colours. Three supervised classifiers were used to classify the samples into the observed seven states of ripeness: fuzzy ARTMAP; learning vector quantization (LVQ); and multilayer perceptron (MLP). It was found that the fuzzy ARTMAP and LVQ classifiers outperformed the MLP classifier with accuracies of 90.3% and 92%, respectively, compared with 83.4%. It is shown that the fuzzy ARTMAP classifier, unlike LVQ and MLP, is able to perform efficient online learning without forgetting previously learnt knowledge. (Original abstract - amended)
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