Tissue detection of natural killer cells in colorectal adenocarcinoma

BACKGROUND: Natural killer (NK) cells represent a first line of defence against a developing cancer; however, their exact role in colorectal cancer remains undetermined. The aim of the present study was to evaluate the expression of CD16 and CD57 [immunohistochemical markers of natural NK cells] in colorectal adenocarcinoma. METHODS: Presence of NK cells was investigated in 82 colorectal adenocarcinomas. Immunohistochemical analysis was performed, using 2 monoclonal antibodies (anti-Fc Gamma Receptor II, CD16 and an equivalent to Leu-7, specific for CD-57). The number of immunopositive cells (%) was evaluated by image analysis. The cases were characterized according to: patient gender and age, tumor location, size, grade, bowel wall invasion, lymph node metastases and Dukes' stage. RESULTS: NK cells were detected in 79/82 cases at the primary tumor site, 27/33 metastatic lymph nodes and 3/4 hepatic metastases; they were detected in levels similar to those reported in the literature, but their presence was not correlated to the clinical or pathological characteristics of the series, except for a negative association with the patients' age (p = 0.031). CONCLUSIONS: Our data do not support an association of NK cell tissue presence with clinical or pathological variables of colorectal adenocarcinoma, except for a negative association with the patients' age; this might possibly be attributed to decreased adhesion molecule expression in older ages

Helicobacter pylori (H pylori) infection in Greece: the changing prevalence during a ten-year period and its antigenic profile

BACKGROUND: To evaluate changes in H pylori infection prevalence in Greece during a ten-year period, and to examine its antigenic profile. METHODS: Three groups of patients were studied. Group O-87: Banked serum samples of 200 consecutive adult outpatients, from the Hepato-Gastroenterology clinic of a teaching hospital at Athens, collected in 1987. Group O-97: Serum samples of 201 similarly selected outpatients from the same Unit, collected in 1997. Group BD-97: Serum samples of 120 consecutive blood donors from the same hospital, collected in 1997. H pylori IgG antibody seroprevalence was studied by a quantitative ELISA. Antigenic profile was studied by western-blot IgG assay, in 62 IgG positive patients of O-97 and BD-97. Results were analyzed by conventional statistics and multivariate regression analysis. RESULTS: The H pylori seroprevalence increased with age in the three tested groups. In O-97, seroprevalence did not differ from that, in BD-97. On the contrary, there was a significant decrease in seropositivity between O-87 and O-97 (59.5% vs 49.2%, p = 0.039). Multiple regression analysis showed that age over 35 years (OR:3.45, 95% CI:1.59–7.49, p = 0.002) and year of patients' selection – that is 1987 or 1997 – (OR:1.73, 95% CI:1.14–2.65 for 1987, p = 0.010), were independent risk factors of H pylori infection. The seroprevalence of CagA+ and VacA+ strains was 77.4% and 58.5%, respectively, and type I(CagA+/VacA+) strains were significantly more common than type II(CagA-/VacA-) strains (59.7% vs 22.6%, p < 0.001). CONCLUSIONS: During a ten-year period, we found a significant decrease of H pylori infection in Greece and our data support the birth cohort phenomenon as an explanation for the age-dependent increase of H pylori infection. The prevalence of CagA and/or VacA positive strains is relatively high, in a country with low incidence of gastric cancer

Comparative study of helicobacter pylori infection in 1987 and 1997, in a sample of adult population in Greece

Helicobacter pylori, the cause of active chronic gastritis, is a risk factor for pepticulcer and gastric malignancies. Persisting serum antibodies against H pylori are characteristic ofthis chronic infection and many studies have shown that the IgG antibody test is positive in morethan 90% of culture-positive patients. Serological data from various parts of the world show that Hpylori infection is a disease associated with low living standards, and everywhere, includingGreece, the prevalence of infection increase with age. Long-term follow-up studies in developedcountries suggest that the age-dependent increase of seropositivity is mainly due to the decreasingrate of childhood infections, often referred as a cohort phenomenon. In contrast, in a populationwith a higher rate of infection, there is also evidence suggesting a constant rate of new infections atall ages, which could result in a similar age-dependent increase of seropositivity. Nevertheless, ithas been shown that some Hpylori genes ( vacA, cagA ) confer different biological properties,which could enhance the in vivo pathogenicity of the bacteria. Thus, recently, there has beeninterest in detecting the Hpylori immunophénotype and in particular, the CagA and VacA statusof Hpylori infection.Aim: The aim of this study was to determine if the birth cohort phenomenon theory or a constantrate of new H pylori infections could better explain the age-dependent increase of H pyloriseropositivity in Greece. We also studied the seroprevalence of Hpylori infection in relation with HBV and HCV and the antigenic profile of H pylori infection in a sample of Greek adultpopulation.Patients and Methods : H pylori seroprevalence was studied determining IgG antibodies byELISA. The estimated sensitivity, specificity, positive and negative predictive value of ELISA testwere 87%, 94%, 95% and 84%, respectively, using histology ( Giemsa stain ) as gold standard.Banked serum samples of 200 consecutive adult outpatients ( 107 men and 93 women ) of theHepato-Gastroenterology Unit of 1st Departement of Propedeutic Medecine ( Athens GeneralHospital, "Laikon" ), in 1987 ( group 0-87 ), aged 15-82 years ( mean age 44.3+17 years ), werecompared with 201 serum samples of similarly selected outpatients of the same Unit ( 123 menand 78 women ), in 1997 ( group 0-97 ), aged 16-85 years ( mean age 45.9+15 years),regardless of the cause of admission, personal history and socio-economic status, in both groupsof patients. The serum samples of 0-97 group of patients were compared with the serum samplesof 120 consecutive blood donors in 1997 ( group EA-97 ), aged 18 - 62 years ( mean age 40+11years ). The HBsAg and anti-HCV status were determined using ELISA tests ( Sorin DiagnosticsSri ) and the antigenic profile was studied in 70 IgG positive patients by western-blot IgG assay(Hycor Biomadical Gmbh, Germany ).Statistical analysis : Both univariate ( t-test, chi-square test, Fisher's exact test, one-way analysisof variance ) and multivariate ( logistic regression ) methods were used to analyze categoricalvariables.Results :I. Age-dependent increase in the prevalence of IgG antibodies was obvious in both crosssectional samples ( 0-87 and 0-97 ). In 1997, this increase continued to the age group 55- 64 years, but in 1987 the prevalence was highest in a younger age group (45-54 years ) ( table 2.21, fig. 2.8 ). A lower rate of infection was noticed in the oldest age groups in bothsamples.II. During the 10-year period the prevalence of Hpylori antibodies fell significantly by 10%units ( from 59.5% in 1987 to 49.2% in 1997 )( p=0.039 ) and this decrease was obvious inall age groups. In 1987, the H pylori prevalence distribution began at 38.7% in theyoungest age group (15-24 years ) and reached 78.1% in the group aged 45 - 54 years,with increase rate at an average of 26% with each decade of age ( table 2.5 ). Ten yearslater, the prevalence increased from 14.2% in the group aged 15-24 years to 67.4% in the55 - 64 years age group and the average increase per decade was 50%, primarily due tothe lower rate of infection in younger age groups.III. In 1997, the total seroprevalence of infection and the prevalence distribution of our sampleresembled that of the blood donors in the same period.IV. In a multivariate model, age over 35 years old, HBsAg seropositivity and patients class(1987) were independent risk factors for seropositivity ( table 2.22 ). On the contrary,gender and anti-HCV seropositivity were not found as independent risk factors. The higherrisk for H pylori seropositivity was found in patients who were born in the decade 1933-1942, in both cross-sectional groups ( 0-87, 0-97 )( table 2.23 ).V. The seroprevalence of CagA and VacA antigens was 77.4% and 58.5%, respectively, andthese rates were relatively constant across gender, age and group of patients (0-87,0-97and EA-97). Type I (CagA+IVacA+) strains were significantly more common than type II(CagA-IVacA-) strains ( 59.7% vs. 22.6% , pO.001 ). The prevalence of the other antigensranged from 41.4% (FlaA) to 84.3% {UreB). Conclusions :I. Although increasing age does increase the risk of Hpylori infection, the fact that patientsfrom early class ( 0-87 ) had higher rates of infection than comparable age patients fromlater class ( 0-97 ), mainly supports the birth cohort phenomenon theory as an explanationfor the increased occurrence of Hpylori infection seen with age.II. The reduction in the infection rate during this 10-years period is compatible with thehypothesis that better socio-economic circumstances and improved hygiene have reducedthe risk of Hpylori infection.III. Chronic HBV infection, but not chronic HCV infection, is an independent risk factor for Hpylori seropositivity.IV. In a country with low rates of gastric cancer, we found a disproportional high rate of CagA+and type I strains of H pylori and these data suggest that CagA and/or VacA status arenot the major factors influencing gastric cancer rates.Η Η pylori λοίμωξη είναι η κύρια αιτία της χρόνιας ενεργούγαστρίτιδος και αποτελεί παράγοντα κινδύνου εμφάνισης πεπτικού έλκους και γαστρικώνκακοηθειών. Η παρουσία για μεγάλο χρονικό διάστημα στον ορό των ασθενών αντισωμάτωνέναντι του βακτηριδίου, αποτελεί χαρακτηριστικό της χρόνιας λοίμωξης και πολλές μελέτες έχουνδείξει ότι η ορολογική δοκιμασία ανίχνευσης IgG αντισωμάτων έναντι του Ηpylori είναι θετική σεποσοστό άνω του 90% μεταξύ των ασθενών με θετική ιστολογική εξέταση. Ορολογικά δεδομένααπό διάφορα μέρη του κόσμου, μεταξύ των οποίων και η χώρα μας, δείχνουν ότι η λοίμωξησυνδυάζεται με χαμηλό επίπεδο διαβίωσης και ότι ο επιπολασμός της λοίμωξης αυξάνει με τηναύξηση της ηλικίας. Συγκριτικές - διαχρονικές μελέτες σε αναπτυγμένες χώρες υποδηλώνουν ότι ηαύξηση του επιπολασμού της λοίμωξης με τη πάροδο της ηλικίας, οφείλεται κυρίως σε ελάττωσητου ποσοστού των λοιμώξεων της παιδικής ηλικίας και άρα σε άθροιση παλαιοτέρων λοιμώξεων,αφού είναι γνωστό ότι στους ενηλίκους το ποσοστό νεομόλυνσης εξουδετερώνεται από τοποσοστό αυτόματης ίασης, θεωρία που συχνά αναφέρεται ως «cohort phenomenon». Σεαντίθεση, σε πληθυσμούς με υψηλό ποσοστό λοίμωξης, υπάρχουν επίσης ενδείξεις ότι ένασταθερό ποσοστό νέων λοιμώξεων κατά την ενήλικο ζωή, έχει ως αποτέλεσμα την αύξηση τηςλοίμωξης με τη πάροδο της ηλικίας.Σκοπόζ : Σκοπός της παρούσης μελέτης είναι να διερευνηθεί εάν η «birth cohort phenomenontheory» ή ο συνεχιζόμενος κίνδυνος λοίμωξης στην ενήλικη ζωή, ερμηνεύουν καλύτερα τηπαρατηρούμενη στη χώρα μας αύξηση του επιπολασμού της Η pylori λοίμωξης με την αύξησητης ηλικίας. Μελετήσαμε επίσης τον συσχετισμό της Ηpylori λοίμωξης με τις χρόνιες HBV και HCV λοιμώξεις, καθώς και τον ανοσοφαινότυπο της λοίμωξης σε δείγμα ενήλικου Ελληνικούπληθυσμού.Ασθενεκ και Μεθοδολογία : Η ανίχνευση της Η pylori λοίμωξης έγινε με μέθοδο ELISA (Ηpylori IgG). Η ευαισθησία, ειδικότητα, θετική προγνωστική αξία και αρνητική προγνωστική αξίατης ELISA, με μέθοδο αναφοράς την ιστολογική εξέταση (χρώση Giemsa), βρέθηκε 87%, 94%,95% και 84%, αντίστοιχα. Δείγματα ορών 200 διαδοχικών ασθενών, που προσήλθαν στο Η/Γ Εξ.Ιατρείο της Α'ΠΠΚ, το 1987 (0-87), ηλικίας 15-82 ετών (μέσης ηλικίας 44.3+17 έτη), συγκρίθηκανμε 201 δείγματα ορών διαδοχικών ασθενών, ηλικίας 16-85 ετών (μέσης ηλικίας 45.9+15 έτη), πουπροσήλθαν στο ίδιο ιατρείο το 1997 (0-97), ανεξαρτήτως αιτίας προσέλευσης, ατομικούαναμνηστικού και κοινωνικο-οικονομικού επιπέδου των ασθενών και των δύο ομάδων. Ταδείγματα 0-97 συγκρίθηκαν με 120 δείγματα ορών διαδοχικών εθελοντών αιμοδοτών, ηλικίας 18-62 ετών (μέσης ηλικίας 40+11 έτη), που προσήλθαν το ίδιο χρονικό διάστημα στην αιμοδοσία τουίδιου νοσοκομείου. Ο προσδιορισμός του HBsAg και των anti-HCV αντισωμάτων έγινε με μέθοδοELISA. Ο ανοσοφαινότυπος της Η pylori λοίμωξης μελετήθηκε σε 70 Η pylori IgG θετικάδείγματα ορών, χρησιμοποιώντας τη μέθοδο western-blot IgG. Για τη στατιστική επεξεργασία τωνδεδομένων χρησιμοποιήθηκαν μονοπαραγοντικές (t-test, x2-test και one way analysiw of variance)και πολυπαραγοντικές ( logistic regression ) μέθοδοι.Αποτελέσιιατα :I. Ο επιπολασμός των IgG H pylori αντισωμάτων βαίνει αυξανόμενος με τη πάροδο τηςηλικίας και στις δύο ομάδες ασθενών του Η/Γ Εξ. Ιατρείου που συγκρίθηκαν ( 0-87 και 0-97 ). Το 1997, παρατηρείται συνεχής αύξηση έως την ηλικία των 55-64 ετών όπουπαρατηρείται και το υψηλότερο ποσοστό λοίμωξης , αλλά το 1987 το υψηλότερο ποσοστόλοίμωξης παρατηρείται σε μικρότερες ηλικίες (45-54 ετών). Στις μεγάλες ηλικίεςπαρατηρείται σταθερή πτώση του επιπολασμού της λοίμωξης και στις δύο ομάδες Τη δεκαετία 87 - 97 ο επιπολασμός των Ηpylori αντισωμάτων έχει ελαττωθεί κατά 10%(από 59.5% το '87, σε 49.2% το '97, ρ= 0.039) και η μείωση είναι εμφανής σε όλες τιςομάδες ηλικιών. Το 1987, ο επιπολασμός της λοίμωξης από 38.7% στις ηλικίες των 15-24ετών, φθάνει το 78.1% στις ηλικίες των 45-54 ετών, με μέσο ρυθμό αύξησης το 26% ανάδεκαετία. Δέκα έτη αργότερα, ο επιπολασμός από 14.2% στις ηλικίες των 15-24 ετών,φθάνει το 67.4% στις ηλικίες των 55-64 ετών, με μέσο ρυθμό αύξησης το 50% ανάδεκαετία.III. Το 1997, τόσο ο επιπολασμός της λοίμωξης των ασθενών του Η/Γ Εξωτερικού Ιατρείου,όσο και η κατανομή της ανά ηλικία, σχεδόν συμπίπτουν με τις παρατηρούμενες στοδείγμα των εθελοντών αιμοδοτών της ίδιας περιόδου.IV. Η πολυπαραγοντική ανάλυση έδειξε ότι ηλικία άνω των 35 ετών, χρόνια HBV λοίμωξη καιχρονική περίοδος (1987), αποτελούν ανεξάρτητους παράγοντες κινδύνου Η pyloriλοίμωξης. Αντιθέτως το φύλο και η χρόνια HCV λοίμωξη δεν αποτελούν παράγοντεςκινδύνου λοίμωξης. Άτομα γεννημένα την δεκαετία 1933-1942, εμφανίζουν τον υψηλότεροκίνδυνο οροθετικότητος.V. Το ποσοστό CagA+ και VacA+ στελεχών Ηpylori ήταν 77.4% και 58.5%, αντίστοιχα καιτα ποσοστά αυτά ήταν σταθερά, ανεξάρτητα φύλου, ηλικίας και ομάδος ασθενών. Ταστελέχη τύπου I ( CagA+ / VacA+ ) απαντώνται συχνότερα από τα στελέχη τύπου II(CagA- / VacA-) (57.2% έναντι 22.6%, ρ<0.001). Η συχνότητα των υπολοίπων αντιγόνωνκυμαίνεται από 41.4% (FlaA) έως 84.3% (UreB).Συυπεράσυατα :I. Αν και αυξανόμενης της ηλικίας αυξάνει ο κίνδυνος Η pylori λοίμωξης, το εύρημα ότιασθενείς της ομάδος 0-87 είχαν υψηλότερα ποσοστά Η pylori λοίμωξης απόαντίστοιχους ασθενείς της ομάδος 0-97, υποστηρίζει τη θεωρία του "birth cohort phenomenon" ως κύρια αιτία της παρατηρούμενης αύξησης του επιπολασμού τηςλοίμωξης με την αύξηση της ηλικίας στο δείγμα μας.Ο επιπολασμός της έχει μειωθεί σημαντικά τη τελευταία δεκαετία στους ασθενείς του Η/ΓΕξωτερικού Ιατρείου και αυτό οφείλεται κυρίως στην ελάττωση του επιπολασμού τηςλοίμωξης στις μικρές ηλικίες.Η χρόνια HBV λοίμωξη αποτελεί παράγοντα κινδύνου Ηpylori λοίμωξης, ανεξάρτητο τουφύλου και της ηλικίας των ασθενών.Το ποσοστό των CagA θετικών στελεχών στη χώρα μας είναι δυσανάλογα υψηλό για τοπαρατηρούμενο ποσοστό γαστρικής κακοήθειας και αυτό θέτει σε αμφισβήτηση τηνσχέση ανοσοφαινότυπου και κλινικής έκφρασης της λοίμωξης

When Crohn′s disease is in remission, more patients complete capsule endoscopy study but less lesions are identified

Background and Aims: Wireless capsule endoscopy (WCE) is used in Crohn′s disease (CD) to define disease extent. We aimed to define WCE detection rate of small bowel ulcerative lesions and completion rate in CD patients. Patients and Methods: A total of 102 consecutive CD patients, who successfully passed patency capsule, were matched to 102 controls. WCE was performed in both patients (in acute phase and CD clinical remission) and controls. Results: Eighty-six (84%) controls versus 62 (61%) patients in the acute phase ( P = 0.003) and 96 (94%) in remission ( P = 0.02) completed WCE study. Gastric passing time was 48 ± 66 min in controls, 66 ± 82 min in CD acute phase ( P = 0.03) and 30 ± 21 min in remission ( P = 0.07). Small bowel passing time was 276 ± 78 min in controls, 299 ± 78 min in the acute phase of CD ( P = 0.04) and 248 ± 89 min in remission ( P = 0.01). Mean capsule endoscopy Crohn′s disease activity index (CECDAI) score was 14 ± 6 in acute small bowel CD, 12 ± 7 in acute small-large bowel CD ( P = 0.08) and 2 ± 2 in both CD types while in remission ( P = 1.00). Small bowel ulcerative lesions in the acute phase were more frequently in distal small bowel. Aphthous ulcers were frequent a month after entering clinical remission and tend to disappear gradually later on. No ulcerative lesions were present in deep remission. Patency capsule is rather safe to exclude small bowel obstruction. Conclusions: (1) A high percentage of patients with active CD do not complete small bowel study with WCE. (2) Small bowel ulcerative lesions in clinical remission were less severe, although at least 6 months are needed in order for them to disappear

Capsule endoscopy retention as a helpful tool in the management of a young patient with suspected small-bowel disease

Capsule endoscopy is an easy and painless procedure permitting visualization of the entire small-bowel during its normal peristalsis. However, important problems exist concerning capsule retention in patients at risk of small bowel obstruction. The present report describes a young patient who had recurrent episodes of overt gastrointestinal bleeding of obscure origin, 18 years after small bowel resection in infancy for ileal atresia. Capsule endoscopy was performed, resulting in capsule retention in the distal small bowel. However, this event contributed to patient management by clearly identifying the site of obstruction and can be used to guide surgical intervention, where an anastomotic ulcer is identified. (c) 2007 The WJG Press. All rights reserved

Evaluation of the direct economic cost per eradication treatment regimen against helicobacter pylori infection in Greece: Do national health policy-makers need to care?

Helicobacter pylori (Hp) management has undoubtedly resulted in a notable economic burden on healthcare systems globally, including Greece. Its cost has never been estimated so far, especially during the recent 10-year unprecedented financial crisis. Direct medical and procedural costs for one attempt "outpatient" Hp eradication treatment were estimated as the following: (I) first-line regimens: 10 and 14 days standard triple, 10 and 14 days sequential, 10 and 14 days concomitant non-bismuth quadruple, 14 days hybrid, (II) second-line salvage regimens: 10 and 14 days levofloxacin-containing triple regimens. Treatment costs using prototypes and/or generic drugs were calculated. Drug prices were collected and confirmed from two official online medical databases including all medicines approved by the Greek National Organization for Medicines. Regimens based on generics were more affordable than prototypes and those including pantoprazole yielded the lowest prices (mean: 27.84 €). Paradoxically, 10-day concomitant and 14-day hybrid regimens (currently providing good (90-94%) first-line eradication rates in Greece) cost the same (mean: 34.76 €). The expenditures for Hp eradication treatment regimens were estimated thoroughly for the first time in Greece. These data should be taken into account by Public Health policymakers both in Greece and the European Union, aiming for a better and less expensive therapeutic approach

Supercontinuum generation in tantalum pentoxide waveguides for pump wavelengths in the 900 nm to 1500 nm spectral region

We characterize the spectral broadening performance in silica clad and uncladTantalum pentoxide (Ta2O5) waveguides as a function of the input pulse central wavelength and polarization, sweeping over a wavelength range from 900 nm to 1500 nm, with an average incident power of 110 mW. The waveguides are 0.7 µm high and between 2.2 and 3.2 µm wide, and the SiO2 top cladding layer is 2 µm thick. We model the dispersion of the higher order spatial modes, and use numerical simulations based on the generalized nonlinear Schrödinger equation to analyze the nonlinear behaviour of the spatial modes within the waveguides as well as the dispersive effects observed in the experiments. We achieve octave spanning supercontinuum with an average power of 175 mW incident on the waveguide at 1000 nm pump wavelength