Evaluation of optimum classification measures used to define textbook outcome among patients undergoing curative-intent resection of gastric cancer.

BACKGROUND: Textbook outcome (TO) is a composite measure reflecting various aspects of services provided to patients with solid malignancies. We sought to evaluate the importance of various TO components previously proposed for gastric cancer. METHODS: Prospectively maintained electronic databases of 1,743 patients treated in two academic surgical centres were reviewed. Six candidate definitions of TO were evaluated based on their ability to accurately predict patients' prognosis by Cox proportional hazards modelling. RESULTS: TO definition combining 10 measures corresponding to complete tumour resection with an uneventful postoperative course showed the best goodness of fit by achieving the lowest values of Akaike (AIC) and Bayesian (BIC) information criteria and the best predictive performance based on the highest value of c-index. The overall median survival was significantly longer for patients with than without textbook outcome (69.0 vs 20.1 months, P < 0.001). TO maintained its prognostic value in a multivariate model controlling for age, sex, comorbidities, treatment, and tumour related variables and was associated with a 39% lower risk of death (HR 0.61, 95%CI 0.51 - 0.73, P < 0.001). Nine variables identified as predictors of TO were used to develop a nomogram showing very good correlation between the predicted and actual probability of achieving TO. The AUC of ROC obtained from the nomogram was 0.752 (95% CI 0.727 to 0.781). CONCLUSIONS: A uniform definition of textbook outcome provides clinically relevant prognostic information and could be used in quality improvement programs for gastric cancer patients.

Clustering of Tadalafil API Samples According to their Manufacturer in the Context of API Falsification Detection.

This paper reports the results of the active pharmaceutical ingredient (API) fingerprint study, organised by the General European Official Medicines Control Laboratory Network (GEON), on tadalafil. A classical market surveillance study, evaluating compliance to the European Pharmacopoeia, was combined with a fingerprint study, the latter to obtain characteristic data for the different manufacturers, allowing the network laboratories to conduct authenticity tests for future samples, as well as to detect substandard and falsified samples. In total, 46 tadalafil API samples from 13 different manufacturers were collected. For all samples fingerprint data was collected through analysis of impurities and residual solvents, mass spectrometric screening, X-ray powder diffraction and proton nuclear magnetic resonance (1H-NMR). Chemometric analysis revealed that all manufacturers could be characterised based on the impurity, residual solvent and 1H-NMR data. Future suspicious samples in the network will therefore be analysed with these techniques in order to attribute the sample to one of the manufacturers. If the sample cannot be attributed, a more profound investigation will be necessary to reveal the origin of the sample. In cases where the suspect sample is claimed to be from one of the manufacturers included in this study, analysis can be limited to the test distinguishing that manufacturer.

GEONs API fingerprint project: Selection of analytical techniques for clustering of sildenafil citrate API samples.

Through its Active Pharmaceutical Ingredient Working Group (API-WG) the General European Official Medicines Control Laboratory (OMCL) Network (GEON), co-ordinated by the European Directorate for the Quality of Medicines & HealthCare (EDQM), regularly organises market surveillance studies for specific APIs for conformity to their monograph in the European Pharmacopoeia. During the past years some studies were combined with a fingerprint study of the APIs. The idea is to obtain a fingerprint for each manufacturer of the API under investigation, allowing the OMCL network to identify future samples as well as to detect substandard and falsified APIs. This paper reports the results of the latest fingerprint study, organised on sildenafil citrate API samples. Seventy-nine samples from 14 different manufacturers were collected throughout the Network. Fingerprint data was collected through Mid-Infrared spectroscopy, Raman spectroscopy, liquid chromatography for related substances, gas chromatography for residual solvents, X-ray diffraction and Nuclear Magnetic Resonance (NMR) spectroscopy. Chemometrics applied to the collected data showed that all manufacturers could be discriminated based on the data of only three of these tests, i.e. gas chromatography for residual solvents, X-ray diffraction and proton NMR. Suspicious API samples for sildenafil citrate will therefore be analysed in the future with the selected techniques in order to link the sample to a manufacturer or demonstrate the absence of such link. If the sample cannot be attributed to one of the manufacturers, further analysis and research on provenance and identity will be required. Of course, if the suspected sample claims to originate from one of the manufacturers included in the study, analysis can be limited to the test distinguishing this manufacturer.

Selectivity of identification of compounds from the group of phosphodiesterase-5 inhibitors (PDE-5i) in falsified products from the Polish market using attenuated total reflectance Fourier transform infrared spectroscopy and X-ray powder diffraction.

Falsified drugs are a growing problem and a great threat all over the world. Searching for easy, fast, not expensive and reproducible methods for identification of active pharmaceutical ingredients (APIs) is an important issue. The application of ATR-IR technique for identification of phosphodiesterase-5 inhibitors (PDE-5i) in falsified products from the Polish market has been demonstrated. Furthermore, the strategy of confirmation of the product's originality inaquick and easy way has been developed. The advantages of this application are: exceptional simplicity, very short measurement time, high selectivity inrelation to structurally similar substances and almost no sample preparation. After validation, developed strategy has been successfully introduced into routine analysis.

Strategy for identification of new psychoactive substances in illicit samples using attenuated total reflectance infrared spectroscopy.

New strategy has been developed for the identification of novel psychoactive substances (NPS) in illicit samples. The methodology was based on the use of attenuated total reflectance Fourier transform infrared spectroscopy (ATR-IR). First pass screening by ATR-IR allows known substances to be rapidly identified, while any non-matching samples are qualified by complementary analytical techniques and then feed back into the spectral libraries. Compounds' identification by ATR-IR was based on the correlation coefficient value. After validation, developed strategy was successfully introduced into routine analysis. Thirty one NPS have been identified in forty five samples. One new opioid was identified and new ATR-IR spectra were acquired, not reported in commercial libraries yet. ATR-IR enabled distinguishing between closely related compounds, even structural isomers. It proved to be an easy and very reproducible tool for screening analysis of NPS, in less than one minute, with no sample destruction, even for very little amount of a sample. Developed and validated strategy may be introduced by other laboratories.

The new versatile general purpose surface-muon instrument (GPS) based on silicon photomultipliers for µSR measurements on a continuous-wave beam.

We report on the design and commissioning of a new spectrometer for muon-spin relaxation/rotation studies installed at the Swiss Muon Source (SµS) of the Paul Scherrer Institute (PSI, Switzerland). This new instrument is essentially a new design and replaces the old general-purpose surface-muon (GPS) instrument that has been for long the workhorse of the µSR user facility at PSI. By making use of muon and positron detectors made of plastic scintillators read out by silicon photomultipliers, a time resolution of the complete instrument of about 160 ps (standard deviation) could be achieved. In addition, the absence of light guides, which are needed in traditionally built µSR instrument to deliver the scintillation light to photomultiplier tubes located outside magnetic fields applied, allowed us to design a compact instrument with a detector set covering an increased solid angle compared with the old GPS.

[Surveillance of West Nile fever in horses in the Czech Republic from 2011 to 2013]. / Surveillance západonilské horecky u koní v Ceské republice v letech 2011-2013.

STUDY AIM: The West Nile virus (WNV) is an important mosquito-borne flavivirus occurring around the world. Occasionally found in Central Europe, the virus spread massively through whole Hungary between 2008 and 2009. The aim of our study was to determine the recent prevalence of the WNV infection in horses in the Czech Republic. MATERIAL AND METHODS: Overall, 2349 serum samples, collected from healthy unvaccinated adult horses in the Czech Republic between 2011 and 2013, were tested. A commercially available competitive ELISA kit (cELISA) was used for this purpose and positive samples were confirmed by virus neutralisation tests using WNV and tick-borne encephalitis virus (TBEV). RESULTS: Altogether 271 of 2348 samples (11.5%) were positive by cELISA. Confirmatory VNT revealed 16 WNV positive samples, 11 of which had titres from 8 to 1024; VNTs with TBEV were negative. Three samples had antibodies against both viruses and the WNV antibody titres were less than or equal to the TBEV antibody titres. A cross reactivity of flaviviruses might have had an impact on the results, but in samples with similar WNV and TBEV titres, co-infection with both pathogens cannot be ruled out either. VNT antibody titres in two horses were inconclusive (cut-off titre 4). The place of birth and transfers (if any) were checked for each WNV seropositive horse. Five WNV positive/TBEV negative samples (0.2%) came from five administrative regions (South Bohemian, Karlovy Vary, Central Bohemian, South Moravian, and Moravian-Silesian) and the respective animals were never moved to a foreign country. Four of these horses never left the farm. Other six WNV positive/TBEV negative horses were imported to the Czech Republic from North America or Central and West Europe and therefore, it is not possible to tell unambiguously whether their infection is autochthonous or imported. CONCLUSION: The results of the present study confirm that WNV antibodies occur sporadically in horses in the Czech Republic. WNV was found to circulate in different parts of the Czech Republic and not only in the South of Moravia.

Direct spectroscopic observation of a shallow hydrogenlike donor state in insulating SrTiO3.

We present a direct spectroscopic observation of a shallow hydrogenlike muonium state in SrTiO(3) which confirms the theoretical prediction that interstitial hydrogen may act as a shallow donor in this material. The formation of this muonium state is temperature dependent and appears below ∼ 70K. From the temperature dependence we estimate an activation energy of ∼ 50 meV in the bulk and ∼ 23 meV near the free surface. The field and directional dependence of the muonium precession frequencies further supports the shallow impurity state with a rare example of a fully anisotropic hyperfine tensor. From these measurements we determine the strength of the hyperfine interaction and propose that the muon occupies an interstitial site near the face of the oxygen octahedron in SrTiO(3). The observed shallow donor state provides new insight for tailoring the electronic and optical properties of SrTiO(3)-based oxide interface systems.

Seroprevalence and risk factors of Neospora spp. in donkeys from Southern Italy.

In some European countries there is an increasing interest on donkey. Despite there are few data regarding the donkey's parasitic diseases especially those with a protozoal etiology as neosporosis. Samples used in the study were collected from 238 domestic donkeys during year 2010 in Southern Italy from 207 females and 31 males of five breeds (Martina-Franca, Amiata, Sicilian-Grey, Ragusano, Sardinian) and crossbreeds with the average age 9 years (1 month - 24 year). Sera were tested by a competitive-inhibition enzyme-linked immunosorbent assay for antibodies against Neospora caninum; the sera were marked positive, if more than 30% inhibition was found. Out of a total 238 donkeys, 28 (11.8%) were found positive for Neospora antibodies with 12% in females and 6% in males. Different seroprevalence 15.4%, 16%, 12% and 8.8% were found in age categories <1 year, 1-4 years, 5-9 years and ≥10 years, respectively. The seroprevalence ranged in different breeds from 36% (Sicilian-Grey) to 0% (Sardinian) and in different use from 17% (for breeding) to 0% (for meat production). Logistic regression analysis demonstrated evidence of a significant (P<0.05) association between crossbreed origin of samples and risk of protozoan infection; age of donkeys was also significant risk factor for protozoan infection. No statistical significant difference (P>0.05) was found among genders and use of donkeys and risk of N. caninum infection. This is the first serological survey for Neospora spp. performed in donkeys.

Importance of spin-orbit interaction for the electron spin relaxation in organic semiconductors.

Despite the great interest organic spintronics has recently attracted, there is only a partial understanding of the fundamental physics behind electron spin relaxation in organic semiconductors. Mechanisms based on hyperfine interaction have been demonstrated, but the role of the spin-orbit interaction remains elusive. Here, we report muon spin spectroscopy and time-resolved photoluminescence measurements on two series of molecular semiconductors in which the strength of the spin-orbit interaction has been systematically modified with a targeted chemical substitution of different atoms at a particular molecular site. We find that the spin-orbit interaction is a significant source of electron spin relaxation in these materials.

Seroprevalence of Toxoplasma gondii and Neospora caninum in slaughtered pigs in the Czech Republic.

In the Czech Republic, sera from 551 clinically healthy adult slaughtered pigs (females, 6-8 months old) were collected during the first half of June in 2010. Sera were tested for Toxoplasma gondii-specific IgG antibodies by an enzyme-linked immunosorbent assay; samples with more than 50% S/P were considered as positive. The same samples were also analysed for Neospora caninum antibodies using a commercial competitive-inhibition enzyme-linked immunosorbent assay; samples with more than 30% inhibition were considered as positive. Antibodies against T. gondii were found in 198 pigs (36%) in all districts with prevalences ranging from 18% to 75%. Antibodies against N. caninum were found in 16 pigs (3%); positive animals were found in 4 districts with prevalences ranging from 1% to 20%. Indication of mixed infections (concurrent presence of both N. caninum and T. gondii antibodies) was found in 8 (1·5%) pigs. The results of our study indicate that pigs in the Czech Republic have a relatively high seroprevalence for T. gondii, while they have only a low seroprevalence for N. caninum. Therefore, natural infection with T. gondii seems to be very common in Czech pigs. It is the first evidence of N. caninum antibodies in pigs in the Czech Republic. These results complete data about N. caninum infection in pigs in Europe.

Toxoplasma gondii and Neospora caninum antibodies in sheep in the Czech Republic.

In the Czech Republic, serum from 547 sheep coming from nine farms was examined for antibodies against parasites Toxoplasma gondii and Neospora caninum by screening ELISA. Antibodies against T. gondii were found in 325 sheep (59%) with prevalence ranging from 11% to 96% in different farms. Antibodies against N. caninum were found in 63 sheep (12%) with prevalence ranging from 4% to 21% in different farms. Mixed infections were found in 53 sheep (10%). It was the first evidence of N. caninum antibodies in sheep from the Czech Republic.

Prevalence of Neospora caninum and Toxoplasma gondii antibodies in wild ruminants from the countryside or captivity in the Czech Republic.

In the Czech Republic, sera from 720 wild ruminants were examined for antibodies to Neospora caninum by screening competitive-inhibition enzyme-linked immunosorbent assay and confirmed by indirect fluorescence antibody test (IFAT); the same sera were also examined for antibodies to Toxoplasma gondii by IFAT. Neospora caninum antibodies were found in 14% (11 positive/79 tested) roe deer (Capreolus capreolus), 14% (2/14) sika deer (Cervus nippon), 6% (24/ 377) red deer (Cervus elaphus), 1% (2/143) fallow deer (Dama dama), 3% (3/105) mouflon (Ovis musimon), and none of 2 reindeer (Rangifer tarandus). Toxoplasma gondii antibodies were found in 50% (7/14) sika deer, 45% (169/377) red deer, 24% (19/79) roe deer, 17% (24/143) fallow deer, 9% (9/105) mouflon, and 1 of 2 reindeer. In 42 samples of wild ruminants that tested positive for N. caninum antibodies, 28 (67% of the positive N. caninum samples) reacted solely to N. caninum. This is the first evidence of N. caninum infection in mouflon, the first N. caninum seroprevalence study in farmed red deer, and the first survey of N. caninum in wild ruminants from the Czech Republic.

Serological survey of Neospora caninum in dogs in the Czech Republic and a long-term study of dynamics of antibodies.

The main aim of the present study was to establish the prevalence of antibodies against Neospora caninum dogs from the Czech Republic and to examine the dynamics of antibody titers during a long-term period. For this purpose, sera of 858 dogs were examined for the presence of anti-N. caninum antibodies using an indirect immunofluorescent antibody test (IFAT). Four groups of dogs of various origins were included in the survey: the first group (A, n=470) comprised dogs purchased by the Czech Army from the civilian sector throughout the Czech Republic, with 22 (4.7%) N. caninum-positive dogs, second group (B, n=115) represented police dogs with no seropositive animal, third group (C, n=195) were pet dog sera collected for veterinary clinic with 5 (2.6%) anti-N. caninum sera and the fourth group (D, n=78) of canine shelter dogs with the seroprevalence of 19.2%. The differences in seroprevalence were significant (P< or =0.01) between groups B and A, and between D and A. None of the serologically positive animals had clinical signs of neurological disorders. Coprological examination did not reveal any dog shedding N. caninum oocysts. The seropositivity rates for N. caninum were analyzed in relation to other data, such as age, breed and gender. Increased prevalence rates of anti-N. caninum antibodies were found in the older age strata of the dog population sample tested in the present study. We found significantly higher (P=0.02) prevalence in 3-3.5-year-old dogs (11.1% of 36), as compared to 1-1.5-years-old dogs (2% of 98). A longitudinal study of antibody dynamics was carried out in 19 initially seropositive dogs over a period of 4 years. The second and third examinations revealed that antibody titers decreased in majority of positive dogs (10, 52.6%), of which in seven cases (36.8%) the titers fell to levels that are currently considered as being seronegative (titer <1:50), or even became undetectable (titer <1:25).

Prevalence of Toxoplasma gondii and Neospora caninum antibodies in wild boars in the Czech Republic.

Sera collected from hunter-killed wild boars (Sus scrofa) during 1999-2005 from seven different regions of the Czech Republic were assayed for antibodies to Toxoplasma gondii by indirect fluorescence antibody test and to Neospora caninum by competitive-inhibition enzyme-linked immunosorbent assay and by indirect fluorescence antibody test. Antibodies to T. gondii were detected in 148 (26.2%) of 565 wild boars with serum dilutions of 1:40 in 40, 1:80 in 40, 1:160 in 27, 1:320 in 19, 1:640 in 18 and 1:1280 in 4 wild boars. Antibodies to N. caninum were detected in 102 (18.1%) of 565 wild boars with 30.1-94.6% inhibition in ELISA; statistical significant differences were observed between sampling regions, ranging from 0% to 31.8%. Sera, positive in ELISA, were examined in IFAT; 58 of 102 (56.9%) were positive with titres 1:40-1:160. Mixed infection (concurrent presence of both T. gondii and N. caninum antibodies) was found in 38 wild boars. It is the first report of antibodies to N. caninum in wild boar. Serological results indicate a common exposure to T. gondii and to N. caninum among wild boars in the Czech Republic.

Seroprevalences of antibodies to Neospora caninum and Toxoplasma gondii in zoo animals.

Neospora caninum is an apicomplexan parasite that causes neuromuscular disease in dogs and abortions in cattle. Little is known about the prevalence of antibodies to this parasite in zoo animals. Sera from 556 animals, from 13 Czech and Slovak zoos were tested for antibodies to N. caninum and Toxoplasma gondii by indirect fluorescent antibody test. Antibodies to N. caninum were found in 31 of 556 zoo animals (5.6%), representing 18 of 114 species tested: Eurasian wolf (Canis lupus lupus), Maned wolf (Chrysocyon brachyurus), fennec (Vulpes zerda), cheetah (Acinonyx jubatus), jaguarundi (Herpailurus yaguarondi), Eurasian lynx (Lynx lynx), Indian lion (Panthera leo goojratensis), fisher (Martes pennanti), blackbuck (Antilope cervicapra), European bison (Bison bonasus), lechwe (Kobus leche), African buffalo (Syncerus caffer caffer), eland (Taurotragus oryx), sitatunga (Tragelaphus spekei gratus), Thorold's deer (Cervus albirostris), Eastern elk (C. elaphus canadensis), Vietnam sika deer (C. nippon pseudaxis) and Père David's deer (Elaphurus davidianus). Titres ranged from 1:40 to 1:2560. The highest prevalence 50% was found in family mustelidae of the order carnivora. Antibodies to T. gondii were detected in 193 of 556 zoo animals (34.7%) representing 72 of 114 species tested, with titres ranging from 1:40 to 1:40960. The highest prevalence 100% was found in families: hyaenidae, mustelidae, ursidae and viveridae of the order carnivora. The results of this study indicate that zoo animals have more exposure to T. gondii than to N. caninum. It is the first report of seroprevalence of antibodies to N. caninum in European zoo animals.

Experimental infection of budgerigars (Melopsittacus undulatus) with a low virulent K21 strain of Toxoplasma gondii.

In total 53 budgerigars (Melopsittacus undulatus) were divided into six groups and orally infected with a suspension of oocysts of low virulent Toxoplasma gondii K21 strain in the doses of 10(2), 10(3), 10(4), 10(5) and 10(6), respectively. Blood was collected from the birds prior to the inoculation and then on days 10, 20 and 30 post infection. Latex-agglutination test (LAT) was used for the detection of antibodies in the inoculated birds. The infected birds showed no apparent signs of disease. The antibodies were found in all but two birds inoculated a dose of 10(2) oocysts. Haematological values remained unchanged after infection. T. gondii was isolated by bioassay in mice from all 37 birds fed 10(3) or more oocysts and 6 of 9 fed 10(2) oocysts. The results demonstrate that budgerigars are resistant to T. gondii infection.

Low virulence of oocysts of Czech Toxoplasma gondii isolates on the basis of biological and genetic characteristics.

The virulence of the oocysts of 7 Czech Toxoplasma gondii isolates was tested. The oocysts were obtained by experimental infection of cats with the tissue cysts of T. gondii isolates from dogs, cats, and rabbits. The cats shed the oocysts in feces, with prepatent periods of 3-5 days postinfection (PI); the patent period was 7-18 days. The number of oocysts shed varied between 0.94 million and 47 million, with 0.66 million-39 million oocysts found in the daily samples of excrement. The cats ceased oocyst production at 11-22 days PI. Sporulated oocysts were used to prepare infective doses of 1 to 10(5) oocysts for oral infection of 10 mice. Deoxyribonucleic acid isolated from 4 T. gondii isolates was used in polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for amplification of the ROP1 gene and restriction of the product of amplification by restriction endonuclease DdeI. On the basis of their biological characteristics, all 7 isolates belonged to the group of "avirulent" strains. In the PCR-RFLP tests, 2 isolates, K9 and K19, showed an "avirulent" strain pattern.

Seroprevalence of Neospora caninum in aborting dairy cattle in the Czech Republic.

A serological survey for antibodies against Neospora caninum in aborting cattle was carried out in the Czech Republic. Serum samples from 463 aborting dairy cows originated from 137 farms from different parts of the Czech Republic were tested for presence of N. caninum antibodies by use of an enzyme-linked immunosorbent assay (ELISA) and an indirect fluorescent antibody test (IFAT). Antibodies (> or = 1:640) to N. caninum were found in 18 (3.9%) of 463 aborting cows. Farm prevalence in aborting cows was 12.4% (17/137). The antibody titres of cows were 1:200 (9 cows), 1:640 (7 cows), 1:1280 (3 cows), 1:2560 (3 cows), 1:5120 (3 cows), 1:10,240 (2 cows) and 1:20,480 (0 cow). A case-control study was conducted to estimate the association of N. caninum infection and abortion. For this 407 serum samples were collected from cows on five dairy farms with repeated occurrence of endemic and sporadic abortion of unidentified etiology. These samples were obtained from aborting cattle (n=44) and normally calving cattle (control group; n=363) and tested for N. caninum antibodies by an immunofluorescent antibody test (IFAT). Overall, 3.19% (13/407) of cows sampled had positive N. caninum fluorescence with a cut-off titre of 1:200. The prevalence of N. caninum was significantly higher (P<0.05) in the aborting group (13.64%; 95% confidence interval (CI): 5.2, 27.4) than in the control group (1.93%; 95% CI: 0.8, 3.9). A strong association between seropositivity and abortion was found, with seropositive cows being eight times more likely to abort than seronegative cows (odds ratio=8; 95% CI: 2.6, 25.1). This first report on the serological prevalence of N. caninum in cows in the Czech Republic verified a strong association between N. caninum infection and abortions in five dairy farms. Thus, the neosporosis should be considered in differential diagnosis of bovine abortion.