Isolation of Helicobacter pylori in gastric mucosa and susceptibility to five antimicrobial drugs in Southern chile

Helicobacter pylori colonizes more than 50% of the world population thus, it is considered an important cause of gastric cancer. The aim of this study was to determine the isolation frequency of H. pylori in Southern Chile from patients with symptomatology compatible with gastritis or gastric ulcer and to correlate these findings with demographic parameters of infected patients and the susceptibility profiles of the isolated strains to the antimicrobial drugs used in the eradication treatments. A total of 240 patients were enrolled in the study. Each gastric biopsy was homogenized and seeded onto blood agar plates containing a selective antibiotics mixture (DENT supplement). Plates were incubated at 37° C in a microaerophilic environment for five days. The susceptibility profiles to amoxicillin, ciprofloxacin, clarithromycin, tetracycline and metronidazole were determined using the E-test method. H. pylori was isolated from 99 patients (41.3%) with slightly higher frequency in female (42% positive cultures) than male (40.2% positive cultures). With regard to age and educational level, the highest isolation frequencies were obtained in patients between 21-30 (55%) and 41-50 (52.6%) years old, and patients with secondary (43.9%) and university (46.2%) educational levels. Nineteen (21.6%) strains showed resistance to at least one antimicrobial drug. Tetracycline was the most active antimicrobial in vitro, whereas metronidazole was the less active. One strain (5.3%) showed resistance to amoxicillin, clarithomycin and metronidazole, simultaneously.

Interferon-gamma mediated up-regulation of caspase-8 sensitizes medulloblastoma cells to radio- and chemotherapy

Loss of caspase-8 expression - which has been demonstrated in a subset of Medulloblastoma (MB) - might block important apoptotic signalling pathways and therefore contribute to treatment resistance. In this study, IFN-gamma mediated up-regulation of caspase-8 in human MB cells was found to result in chemosensitization to cisplatin, doxorubicin and etoposide, and sensitisation to radiation. These effects were more prominent in D425 and D341 MB cells (low basal caspase-8 expression) when compared to DAOY MB cells (high basal caspase-8 expression). IFN-gamma mediated chemosensitization and radiosensitization effects were reduced by treatment with the caspase-8 specific inhibitor z-IETD-fmk. Treatment of IFN-gamma resulted in activation of STAT1 in DAOY MB cells and to a lesser extent in D425, but not in D341, indicating that IFN-gamma acts in MB cells through STAT1-dependent and -independent signalling pathways. Taken together, our results demonstrate that IFN-gamma mediated restoration of caspase-8 in MB cells might enhance apoptotic pathways relevant to the response to chemo- and radiotherapy.

Antisense treatment of IGF-IR induces apoptosis and enhances chemosensitivity in central nervous system atypical teratoid/rhabdoid tumours cells

Central nervous system (CNS) atypical teratoid/rhabdoid tumours (AT/RT) are among the paediatric malignant tumours with the worst prognosis and fatal outcome. Insulin-like growth factor I receptor (IGF-IR) protects cancer cells from apoptosis induced by a variety of anticancer drugs and radiation. In the present study, IGF-IR was expressed in 8/8 primary AT/RT as detected by immunohistochemistry. Moreover, we found IGF-I and IGF-II mRNA in BT-16 CNS AT/RT cells and IGF-II mRNA in BT-12 CNS AT/RT cells, and autophosphorylated IGF-IR in both cell lines, indicating the potential presence of an autocrine/paracrine IGF-I/II/IGF-IR loop in CNS AT/RT. IGF-IR antisense oligonucleotide treatment of human CNS AT/RT cells resulted in significant down-regulation of IGF-IR mRNA and protein expression, induction of apoptosis, and chemosensitisation to doxorubicin and cisplatin. These studies provide evidence for the influence of IGF-IR on cellular responses to chemotherapy and raise the possibility that curability of selected CNS AT/RT may be improved by pharmaceutical strategies directed towards the IGF-IR.

Health-related quality of life in patients receiving reduced-intensity conditioning allogeneic hematopoietic stem cell transplantation

Reduced-intensity conditioning allogeneic HSCT (RIC) has less regimen-related morbidity and mortality than myeloablative allogeneic HSCT (MT) offering allogeneic transplantation to patients otherwise excluded. Whether these advantages improve health-related quality of life (HRQL) is unknown. We examined the HRQL effects of RIC and MT in patients with hematological diseases pre-transplant (baseline), days 0, 30, 100, 1 and 2 years following HSCT. HRQL was measured using the Short Form-36 Health Survey and the Functional Assessment of Cancer Therapy - General and BMT. Data were analyzed using mixed linear modeling adjusting for baseline HRQL differences. Patients (RIC=41, MT=35) were predominately male (67%), in remission/stable disease (65%) with an Eastern Cooperative Oncology Group status <or=1 (97%). HRQL progressively improved (P<0.01) in both groups with higher scores at day 100 compared to days 0 and 30; there was no difference between groups during early recovery. At 2 years, all survivors (n=43) reported HRQL similar or better than baseline. Results suggest RIC and MT patients experience a similar pattern of HRQL improvement during early recovery. Two-year survivors report a return to baseline or better in HRQL by day 100, with the exception of physical health in MT patients.

Epidemiological, biological and histological characterization of patients with indeterminate third-generation recombinant immunoblot assay antibody results for hepatitis C virus

We studied the epidemiological, laboratory and histological characteristics of a group of patients with positive antibodies against hepatitis C virus (HCV) as determined by third-generation enzyme-linked immunosorbent assay (ELISA), and with indeterminate HCV antibody positivity as established by third-generation recombinant immunoblot assay (RIBA-3). The results obtained were compared with those recorded in a group of RIBA-3-positive patients. Both groups correspond to blood donors in whom the prevalence of hepatitis C is low. There were no statistically significant intergroup differences in mean age, or in the presence of infection risk factors. RNA positivity was much more frequent in the RIBA-positive group (71%vs 10%; P < 0.05), as was transaminase elevation during the 3 years of follow-up (54%vs 13%; P < 0.05). In 46% of the RIBA-indeterminate patients the liver biopsy proved normal, or only liver steatosis or minimal changes were detected, while 33% had persistent chronic hepatitis, and 21% showed active chronic hepatitis. A mean Knodell index score of 2.28 was recorded; 50% of the subjects showed no fibrosis, 46% grade 1 fibrosis (fibrous portal expansion), 4% grade 2 fibrosis (bridging fibrosis), and none grade 3 fibrosis (liver cirrhosis). In the RIBA-positive group, a greater percentage of patients had active chronic hepatitis, a greater Knodell index, and increased-grade fibrosis. It can be concluded that the RIBA-3-indeterminate group is epidemiologically similar to the RIBA-3-positive series, although with a lesser prevalence of laboratory test alterations, a lower viral replication index, and more likely to have benign disease - particularly in subjects without viral replication.

Anti-genotoxic effect of Aloysia triphylla infusion against acrylamide-induced DNA damage as shown by the comet assay technique

Aloysia triphylla a perennial, bushy plant originally from South America has long been used in traditional medicine. Its aqueous extract contains considerable amounts of polyphenolic compounds, namely flavonoids and phenolic acids. In view of the interest in natural phenolic compounds as antioxidant in preventive medicine, this study was undertaken to investigate the chemoprotective effects of cedron leaves infusion against the genetic damage induced by acrylamide (AA) by using the alkaline version of the comet assay technique. Mice were separated in nine groups (eight animals each): (I) untreated, (II) negative control, (III) treated with infusion of cedron leaves 5%, 20 days twice a day, (IV) treated with AA (5 mg/kg b.w.), (V) treated with AA (20 mg/kg b.w.), (VI) treated with AA (30 mg/kg b.w.), (VII) treated with AA (50 mg/kg b.w.), (VIII) pretreated with infusion and treated with AA (50 mg/kg b.w.) and (IX) positive control (cyclophosphamide, 20 mg/kg b.w.). Three hundred blast cells were digitally evaluated per animal from three different slides (100 each). Media of tail moment (TM) values were analyzed by ANOVA test. No statistical differences (p>0.05) were found between untreated animals, negative control and infusion-treated mice. A single dose of AA-induced genetic damage as revealed by a statistically significant increase in TM values (p<0.01). Pretreatment with infusion prior to AA injection significantly reduces the capacity of AA to induce genetic damage. In these conditions, tail moments values did not differ from data obtained in negative control (p>0.05) and exhibit statistical differences from animals treated only with AA (p<0.01). Cell viability was at least 90% in all cases as measured by the trypan blue exclusion method. The ferric reducing ability of plasma (FRAP) method reveals that the plasma of infusion-treated mice has a significantly higher antioxidant capacity than plasma from controls (p<0.01). The results suggest that the infusion could exerts an in vivo chemo protective action, probably due to its scavenging potency towards free radicals.

Telomerase inhibition, telomere shortening, cell growth suppression and induction of apoptosis by telomestatin in childhood neuroblastoma cells

Neuroblastoma is a tumour derived from primitive cells of the sympathetic nervous system and is the most common extracranial solid tumour in childhood. Unfavourable tumours are characterised not only by structural changes, including 1p deletion and amplification of the MYCN proto-oncogene, but also by high telomerase activity. Telomeric G-rich single-stranded DNA can adopt in vitro an intramolecular quadruplex structure, which has been shown to inhibit telomerase activity. In this study, we examined telomestatin, a G-quadruplex interactive agent, for its ability to inhibit telomere maintenance of neuroblastoma cells. Telomere length was determined by the terminal restriction fragment method, telomerase activity was measured by a quantitative telomeric repeat amplification protocol, and the expression of human telomerase by quantitative real-time polymerase chain reaction (RT-PCR). Short-term treatment with telomestatin resulted in dose-dependent cytotoxicity and induction of apoptosis. Long-term treatment with telomestatin at non-cytotoxic, but still telomerase activity-inhibiting, concentrations resulted in telomere shortening, growth arrest and induction of apoptosis. These results suggest that the effect of telomestatin is dose-dependent and at least 2-fold. Prolonged low-dose treatment with telomestatin limits the cellular lifespan of NB cells through disruption of telomere maintenance.

[Demography of oncologic practitioners working in France. Projection elements for the next 30 years]

In the early eighties, French medical regulatory authorities have decided to control the access to medical studies by restricting the number of admittances. From that date, the numerous clauses was unchanged, leading the physicians to observe a deep reduction in the number of young oncologists. The goal of this study was to define precisely the demography of French medical oncologists and the needs for new specialists. Our model used data from a wide range of sources was developed under the guidance of epidemiologists. We determined current and projected numbers and demographics of oncologists in France workforce from 2002 to 2032. The number of oncologists and physicians implicated in oncology (organ specialists, radiotherapists and paediatricians) entering the marked in the next few years will not be modified. Consequently, the number of physicians will dramatically decrease in the next 15 years resulting in a 25% global working-age population reduction. Our present analysis indicates that the number of oncologists will not be sufficient to meet future demand. Our data suggests that steps should be taken to stop the ongoing decline in the number of physicians involved in oncology and the decline of physicians in training. Consideration should be given to actions designed to increase the number of oncologists in practise in the years ahead.

[Relationship between serum testosterone levels and prostatic cancer]

INTRODUCTION

The association between testosterone and prostate cancer badly is understood. The testosterone levels are not conclusive to distinguish benign prostate processes of malignant. The objective of our work is to determine the relation between levels of serum testosterone and prostate cancer.

MATERIAL AND METHOD

38 patients with prostate cancer and a control group of 32 were studied in prospective form, with ages that fluctuated between the 50 and 80 years. The total and free testosterone was determined by radio-immunoensayo. The statistical analysis was descriptive inferential, with bands of 95% confidence.

RESULTS

The average values of total and free testosterone, were significantly smaller in patients with prostate cancer. Any correlation between gleason, prostate antigen and stage with testosterone, was not demonstrated.

CONCLUSIONS

Our work demonstrated that the testosterone is significantly smaller in the patients with prostate cancer that in the controls.

[Intraprostatic BCG vaccine in patients with prostatic cancer. Expression of interferon gamma and interleukin 4 (a preliminary study)]

The BCG treatment in the superficial bladder cancer is utilized since 1976. There are some animal experiences with BCG intraprostatic in dogs with prostatic cancer.

GOAL

determine if insitu BCG vaccine increase the prostatic immunity in patients with prostatic cancer.

MATERIAL AND METHOD

Three patients with D stage prostatic cancer where injected with 0.3-0.5 mg of BCG vaccine in the prostate. An histological picture where made in the some place before and after the injection. A RT-PCR study was made for gamma Interferon and Interleukin-4.

RESULTS

In two patients we observed gamma interferon expression (67%) respect the control, this produce an increase of the cytotoxic T lymphocytes, natural killer cells and macrophagos, that have antitumoral action. One patient increased the interleukin-4 that means production of T helper lymphocytes and B lymphocytes. There wasn't complications.

CONCLUSIONS

The BCG vaccine injected in prostatic tissue of patients with prostatic cancer, produces an increase of cytotoxic T lymphocytes and natural killer cells, with antitumoral action.

NK cell-mediated lysis of autologous antigen-presenting cells is triggered by the engagement of the phosphatidylinositol 3-kinase upon ligation of the natural cytotoxicity receptors NKp30 and NKp46

Interleukin-2 (IL-2)-activated polyclonal or clonal NK cells lysed autologous antigen presenting cells (APC) through the engagement of the natural cytotoxicity receptors (NCR) NKp30 and NKp46. NK cell-mediated cytolysis of APC correlated with the surface density of these NCR. Indeed, NK cell clones bearing low amounts of NKp30 and NKp46 did not lyse autologous APC, whereas NK cell clones with bright expression of these NCR efficiently killed autologous APC. Upon masking of NKp30 or NKp46 by specific monoclonal antibodies a strong reduction (by 50%) of APC lysis could be detected and the complete inhibition was achieved by the simultaneous masking of these NCR. Interestingly, NK cell-mediated APC lysis was impaired by the phosphatidylinositol 3-kinase (PI-3 K) inhibitors LY294002 or wortmannin. Similarly, these drugs strongly reduced NK cell activation triggered by NKp30 or NKp46 in a re-directed killing assay as well as the activation of Akt/PKB, substrate of PI-3 K, induced by the engagement of these receptors. Altogether, these findings strongly suggest that NCR are responsible for the killing of autologous APC through the activation of PI-3 K.

Role of NKG2D in tumor cell lysis mediated by human NK cells: cooperation with natural cytotoxicity receptors and capability of recognizing tumors of nonepithelial origin

NKG2D is a recently described activating receptor expressed by both NK cells and CTL. In this study we investigated the role of NKG2D in the natural cytolysis mediated by NK cell clones. The role of NKG2D varied depending on the type of target cells analyzed. Lysis of various tumors appeared to be exclusively natural cytotoxicity receptors (NCR) dependent. In contrast, killing of another group of target cells, including not only the epithelial cell lines HELA and IGROV-1, but also the FO-1 melanoma, the JA3 leukemia, the Daudi Burkitt lymphoma and even normal PHA-induced lymphoblasts, involved both NCR and NKG2D. Notably, NK cell clones expressing low surface densities of NCR (NCR(dull)) could lyse these tumors in an exclusively NKG2D-dependent fashion. Remarkably, not all of these targets expressed MICA/B, thus implying the existence of additional ligands recognized by NKG2D, possibly represented by GPI-linked molecules. Finally, we show that the engagement of different HLA class I-specific inhibitory receptors by either specific antibodies or the appropriate HLA class I ligand led to inhibition of NKG2D-mediated NK cell triggering.

[Helicobacter pylori antibiotic sensitivity by microdilution]

The gastric pathogen Helicobacter pylori has been recognized as the major aetiologic agent of chronic gastritis and peptic ulcers and also a risk factor for gastric cancer; eradication of H pylori prevents peptic ulcer recurrence and may also decrease the prevalence of gastric cancer in high risk populations around the world. Currently the only accepted indication for treatment is ulcer disease and maltosa, infected with Helicobacter pilory. However treatment is difficult and easily develops resistance. The elaboration of an antibiotic profile is recommended after a treatment failure. There is a lack of information in developing countries so the aim of this work was to determine the antibiotic profile of 51 strains isolated from patients gastric biopsies attended at Hospital San Juan de Dios in Costa Rica, using egg yolk broth and finding a resistance of 63.0% to metronidazole with a breakpoint of 8.0 microg/ml and 20.0% resistance to tetracycline (MIC1.0 microg/ml), 6.0% to clarithromicyn with a MIC of 0.125 microg/ml. There was no resistance to amoxicilin (MIC 0.015 microg/ml). The microdilution technique is very laborious, but highly reproducible with results accordingly to previous work, and we recommended it for the designing of therapeutical scheme.

[Our experience with 1 mg BCG vaccine instillation in T1 stage cancer of the bladder]

We studied 67 patients with bladder cancer in stage T1, with terminated BCG treatment and in pursuit. No stage Ta neither carcinoma in situ was included. The protocol was: beginning of treatment upon retiring vesical catheter, instilation of 1 mg of liofilized BCG vaccine (16 x 10(6) bacilles) in 40-50 ml of intravesical saline solution. A weekly instilation during the first month. An instilation each 15 days during the second and third month and one monthly until complete 12 months of treatment. Also was carried out an study of T lymphocites and cytokines.

RESULTS

The average followup of the 67 patients treated was 51.3 months. 17 patients relapses (25.4%). A 33% were grade 3 and 27% grade 2. Like complications there was a case of inguinal TBC adenititis, 2 TBC prostatitis, 2 TBC cistitis and 5 cases of slight disuric syndrome. The study of subpopulations of lymphocites in peripheral blood demonstrated a significant increase of CD3 and CD4/CD8 ratio. The interleukin 2 measurement in serum also increased significantly after the BCG instilations.

CONCLUSIONS

Our protocol gets similar results to the higher doses, but with minimal complications diminishing the relapses of the tumors in stage T1. A monthly maintenance dose would help to maintain immunity.

Melatonin and the reduction or alleviation of stress

In a double blind and placebo controlled study designed to investigate the effect of melatonin administration at 13:00 hr on menstrual characteristics, prolactin, and premenstrual syndrome-like symptoms during simulated eastward travel, it was noted that melatonin reduces or alleviates the stress associated with the simulated travel. Bright lights were utilized to simulate eastward movement across six time zones. Melatonin (10 mg) was given to healthy females for 5 consecutive days during the late follicular and early luteal phases of the menstrual cycle. Hourly blood samples, used for analysis of melatonin and prolactin levels, were obtained for 24 hr before entering the dose administration phase of the study and again on the last dose day. Volunteers also completed a profile of moods state questionnaire upon waking on each of 8 days which overlapped the in-house dose administration days. The placebo group showed a prolactin peak at 13:00 hr (dose time) on the last dose day/blood draw, while the melatonin group showed a prolactin peak at 15:00 hr. The prolactin peak at 13:00 hr is likely the result of stress, since stress is known to elicit the release of prolactin. The peak at 15:00 hr in the melatonin group was likely elicited by the administration of melatonin. Stress reduction in the melatonin group was supported by results from the profile of moods state questionnaire. The melatonin group consistently demonstrated scores indicative of less stress.

[Evaluation of a fast urease test for the detection of Helicobacter pylori]

Helicobacter Pylori colonize the gastric mucosa and their adaptation to this environment is related with its high activity urease. This enzyme hydrolyzes the gastric urea, neutralizing the acid environment of the bacteria. Based on that reaction numerous presumptive diagnosis tests, have been developed using a solution of urea (usually 6%) with a pH indicator (usually 0.05% fenol-red); nevertheless, the color changes are so light that some persons do not detect it. For that reason, a modification of that reaction was proposed using a mix of pH indicators (0.05% fenolred and 0.002 bromothymol blue) which induces a color change from light green to deep purple. Also, the reaction of urease was evaluated using only bromothymol blue. The reaction using fenol red as indicator showed the higher values for sensitivity of 58.8% and the specificity of 66.6%; whereas using only bromothymol-blue those values were 46 y 71.4% respectively. The efficiency of the test using fenol-red or the mix of this bromothymol- was 64.2 y 62.2%, respectively; however, the mix of indicators induce a change color easily detected, because of changes from ligh-green to deep-purple.

[Non-aneurysmatic aortic dysphagia]

Esophageal compression by a vascular structure is a rare cause of dysphagia, the aberrant right subclavian artery being the most common congenital abnormality. Aortica dysphagia is usually observed in the elderly, especially in hypertensive women with cardiopathy and degenerative osteopathy. We report a 73-year-old woman with dysphagia, caused by a non-aneurysmatic aortic elongation, who presented progressive dysphagia, which ended in aphagia associated with heart failure. The diagnostic approach to these patients is discussed. The patient received cinitapride and, following treatment for heart failure, remains asymptomatic after a 3-year follow-up period, although manometric alterations persist.

[Focal nodular liver hyperplasia of atypical presentation]

Focal nodular hyperplasia is a benign hepatic tumor that usually appears in young women. Diagnosis of focal nodular hyperplasia is often incidental when an ultrasonography or computed tomography is performed by other reasons, because its course is generally asymptomatic; the presence of a central fibrous scar is characteristic. Management in focal nodular hyperplasia must be conservative, with ultrasonographic follow-up, and it only must be treated when patients are symptomatics or in case of tumoral enlargement. We report a case of FNH in which symptomatic presentation and the absence of central stellate scar in ultrasonography, computed tomography and magnetic resonance leads to a misdiagnostic of hepatic adenoma, that conditioned a surgical resection. The later examination was diagnostic of focal nodular hyperplasia.

Jejunogastric intussusception: a rare complication of gastric surgery

Jejunogastric intussusception is a rare complication of gastric surgery. We report a case in a 41-year-old woman subjected to gastrojejunostomy with truncal vagotomy 3 years before for pyloric stenosis. The jejunogastric intussusception was diagnosed by upper gastrointestinal series, ultrasonography, and computed tomography. Surgical management consisted of reduction and fixation. Treatment should be as early as possible to prevent gangrene of the invaginated segment.