Colonic adenosquamous carcinoma and mucinous adenocarcinoma with microsatellite instability

A 43-year-old man presented with two-month history of fatigue, weakness, paleness, rectal bleeding, sweating, and weight loss of 10 kg in the past one month. A complete blood count revealed anaemia. The patient underwent a right hemicolectomy. The microscopic examination revealed an adenosquamous carcinoma associated with a mucinous adenocarcinoma in a patient with microsatellite instability due to loss of MLH1 and PMS2 expression and retention of MSH2 and MSH6 expression in both the squamous and glandular components. We also observed an atypical immunohistochemical phenotype in the adenocarcinoma component showing CK7 expression and reduced CK20 and CDX2 expression.

Population structure of Squatina guggenheim (Squatiniformes, Squatinidae) from the south-western Atlantic Ocean

Population genetic analyses based on both mitochondrial cytochrome b and the internal transcribed spacer 2 of recombinant (r)DNA genes were implemented to examine hypotheses of population differentiation in the angular angel shark Squatina guggenheim, one of the four most-widespread endemic species inhabiting coastal ecosystems in the south-western Atlantic Ocean. A total of 82 individuals of S. guggenheim from 10 sampling sites throughout the Río de la Plata mouth, its maritime front, the outer shelf at the subtropical confluence and the coastal areas of the south-west Atlantic Ocean, were included. The analysis of molecular variance (AMOVA) based on the second internal transcribed spacer (its-2) region supports that the samples from the outer shelf represent an isolated group from other sites. Historical gene flow in a coalescent-based approach revealed significant immigration and emigration asymmetry between sampling sites. Based on the low level of genetic diversity, the existence of a long-term population decline or a past recent population expansion following a population bottleneck could be proposed in S. guggenheim. This demographic differentiation suggests a degree of vulnerability to overexploitation in this endemic and endangered south-west Atlantic Ocean shark, given its longevity and low reproductive potential.

Factors affecting the distribution of copulatory plugs in rhesus monkeys (Macaca mulatta) on Cayo Santiago

Although the proximate mechanisms behind the formation of copulatory plugs are well understood, their distribution and function among primates remain largely unstudied. During a study of female rhesus macaque (Macaca mulatta) mating behaviour on Cayo Santiago, we examined the pattern of the distribution of visible copulatory plugs among females and their potential relationship to female reproductive traits and sexual skin colouration. Our results indicate that non-pregnant females were observed more frequently with visible copulatory plugs than were pregnant females. Female parity status, age and rank were unrelated to copulatory plug observation. Genital colouration components were higher among females observed with copulatory plugs. We suggest that although copulatory plugs are generally thought of in terms of male physiology, plug observation may also be affected by female reproductive status.

Phase II trial of erlotinib maintenance therapy after platinun-based chemotherapy in advanced non-small cell lung cancer (NSCLC)

e19013

Background: phase II trial-efficacy & toxicity of sequential erlotinib in advanced NSCLC after platinum-based CT Methods: Pts with adv NSCLC, PS 0/1, adequate renal, hepatic and bone marrow function, no PD after CT. Treatment: erlotinib 150 mg/day starting 3–4 weeks after CT until progression. Safety was evaluated monthly and tumor evaluation bimonthly. Results: 47 pts enrrolled:42(89%)stageIV & 5(11%)wet IIIB, all valid for response & toxicity. Median age 62 y(r:39 -77): 39(83%) males and 8(17%) females. Histology: adenocarcinoma 8(61.7%), bronquioloalveolar 3(6.4%), large cell 3(6.4%), squamous12(25.5%). PS 0: 23(49%), PS 1:24(51%). 38(81.9%) completed 6 cycles of CT. Response: CR: 1(2.1%), PR: 2(51.1%), EE: 22 (46%). Sequential erlotinib improved RR in 6 (12.8%), 23 (48.9) prolonged stabilization, 18 (38.3%) had progression. Median TTP and OS were 9.4 m (95% CI, 4.96–13–84), and 19.23 m (95% CI, 8.82–29.64). No significant differences in TTP according to age, sex, PS, histology or previous response to CT, but yes depending on RR to erlotinib: PR: 31.5 m (95% CI 15.37–47.63), EE: 12.8 m (95% CI, 10.58–15.03), PD: 6.3 m (95% CI, 5.36–7.3), p < 0.001; and moreover depending on smoking status: Never: 21.67 m(95% CI, 5.39–37.94), previous smoker > 5 years: 14.03 m(95% CI, 10.77–17.30), previous smoker 1 year: 7.77 m(95% CI, 7.62–7.91), current smoker: 5.9 m(95% CI, 5.12–6.34), p <0.001. In Cox-regression model, smoking status ( p< 0.001), and response to erlotinib (p=0.002) were associated with a significant difference in TTP. Similar results in OS, although in Cox-regression model only never smoker or > 5 years previous smoker pts had a significant better survival. Toxicity: The most frequent was skin rash, grade (g) 1 in 11(23.4%), g 2: 16(34%) and g 3: 3(6.4%). Only 1 p had diarrea g 3, and no other side effects were observed. We found a significant benefit in p with g 2–3 skin toxicity respect g 0–1, in both TTP( p= 0.0003) and OS (p= 0.0014). Conclusions: Erlotinib-maintenance therapy after platinum-based CT had promising results. Pts with the best benefit were those with response to erlotinib, in never or past (> 5 years) smokers and with g 2–3 skin toxicity.

No significant financial relationships to disclose.

Antimicrobial susceptibility of Helicobacter pylori determined by the E test using tetrazolium egg yolk agar

Metronidazole and tetracycline E tests were compared to an agar dilution method for the antimicrobial susceptibility testing of Helicobacter pylori. Sixteen strains were tested by using tetrazolium egg yolk (TEY) agar. The characteristic E test inhibition ellipse was clearer on TEY agar than on standard blood agar and gave results comparable to those of the agar dilution test. The use of TEY medium is preferable to that of blood agar medium in E test MIC determinations for H. pylori.

Tumor necrosis factor alpha-induced apoptosis in cardiac myocytes. Involvement of the sphingolipid signaling cascade in cardiac cell death

In the present study, it was shown that physiologically relevant levels of the proinflammatory cytokine TNFalpha induced apoptosis in rat cardiomyocytes in vitro, as quantified by single cell microgel electrophoresis of nuclei ("cardiac comets") as well as by morphological and biochemical criteria. It was also shown that TNFalpha stimulated production of the endogenous second messenger, sphingosine, suggesting sphingolipid involvement in TNFalpha-mediated cardiomyocyte apoptosis. Consistent with this hypothesis, sphingosine strongly induced cardiomyocyte apoptosis. The ability of the appropriate stimulus to drive cardiomyocytes into apoptosis indicated that these cells were primed for apoptosis and were susceptible to clinically relevant apoptotic triggers, such as TNFalpha. These findings suggest that the elevated TNFalpha levels seen in a variety of clinical conditions, including sepsis and ischemic myocardial disorders, may contribute to TNFalpha-induced cardiac cell death. Cardiomyocyte apoptosis is also discussed in terms of its potential beneficial role in limiting the area of cardiac cell involvement as a consequence of myocardial infarction, viral infection, and primary cardiac tumors.

Metronidazole and clarithromycin resistance in Helicobacter pylori determined by measuring MICs of antimicrobial agents in color indicator egg yolk agar in a miniwell format. The Gastrointestinal Physiology Working Group of Universidad Peruana Cayetano Heredia and the Johns Hopkins University

Resistance of Helicobacter pylori to metronidazole often causes failure of commonly used combination drug treatment regimens. We determined the MICs of metronidazole and clarithromycin against 18 H. pylori strains from Peru using tetrazolium egg yolk (TEY) agar. The MIC results obtained by agar dilution with petri dishes were compared with the results found through a miniwell format. The results of the two protocols for measuring drug susceptibility differed by no more than 1 dilution in all cases. On TEY agar, bright-red H. pylori colonies were easy to identify against a yellow background. Sixty-one percent (11 of 18) of the strains were resistant to metronidazole (MIC, > or = 4 micrograms/ml) and 50% (9 of 18) were resistant to clarithromycin (MIC, > or = 0.125 micrograms/ml), whereas none (0 of 5) of the strains tested were resistant to tetracycline (MIC, > or = 1 micrograms/ml). Thus, the prevalence of metronidazole and clarithromycin resistance in Peru is higher than that in developed regions of the world. The miniwell plate with TEY agar allows easy H. pylori colony identification, requires about one-third less of the costly medium necessary for petri dish assaying, conserves space, and yields MICs equivalent to those with agar dilution in petri dishes.

Airway responsiveness to methacholine and risk of asthma in patients with allergic rhinitis

To find out whether airway hyperresponsiveness is associated with a greater risk of asthma in subjects with allergic rhinitis, 66 nonasthmatic patients with allergic rhinitis underwent inhalation challenge with methacholine. Each patient was reevaluated prospectively at least once each year and a diagnosis of asthma was accepted if the subject developed episodic wheezing and/or cough plus airway obstruction and at least a 15% increase in FEV1 after inhaled salbutamol. Those subjects who developed asthma and ten individuals who did not develop asthma were rechallenged after the first asthma symptoms or at the end of the followup period, respectively. Risk of developing asthma during the followup period (mean of 43.8 months, range 36 to 70) was similar (P > .05) in those individuals who previously had airway hyperresponsiveness (2 of the 19 patients), when compared with subjects who were previously nonresponders (4 of the 47 patients). Further, in those subjects who developed asthma, geometric mean (range) PC20 decreased from 11.75 (0.40 to 50) during the initial evaluation to 1.66 (0.15 to 11.07) mg/mL after the first asthma symptoms (P < .05). No significant modifications of PC20 were detected in subjects who did not develop asthma. We conclude that a single determination of methacholine PC20 is not a reliable marker of the subsequent development of asthma in patients with allergic rhinitis.

Specific IgE antibodies in nasal secretions: correlation with serum values and clinical tests

The presence of specific IgE in external secretions and the possibility of quantifying it has aroused the interest of many research workers. Nevertheless, there is still disagreement with regard to how useful this practice is from a clinical point of view. We have compared the presence of Dermatophagoides pteronyssinus (Dp) specific-IgE in the nasal secretion of 17 patients suffering from rhinitis with the results of prick tests and nasal and/or conjunctival challenge tests. As a preliminary step we have updated techniques and made a correlation between the parameters mentioned. The results for total IgE (n = 17) show a correlation coefficient (r = .39, NS) between serum values (251 +/- 239) U/L and those obtained in nasal secretion (28 +/- 36) U/L. (2) Serum and nasal-Dp-specific-IgE values (13 +/- 15 and 5 +/- 9, respectively: (r = .72, P = .0011) match in 14 of the 17 determinations. In two of them, the serum values of Dp-specific-IgE, but not the nasal ones, match the in vivo tests. In the others, it is the nasal secretion determination that matches the in vivo tests while the serum and nasal determinations match (82%). These results match in 86% of cases with prick tests and in 93% with nasal/conjunctival challenge tests.(ABSTRACT TRUNCATED AT 250 WORDS)