A quantitative immunochemical faecal occult blood test is more efficient for detecting significant colorectal neoplasia than a sensitive guaiac test

BACKGROUND: The sensitive guaiac faecal occult blood test, Haemoccult SENSA (HOS; Beckman Coulter, Fullerton, CA, USA), is our standard screening test for significant colorectal neoplasia. We evaluated an automatically-developed, quantified human haemoglobin immunochemical faecal test, OC-MICRO (Eiken Chemical Co., Tokyo, Japan), to improve test specificity and so reduce the colonoscopy burden. AIM: To compare guaiac faecal occult blood test and immunochemical faecal test diagnostic efficacy and costs for identifying significant neoplasia. METHODS: Colonoscopies were performed on patients who prepared three daily guaiac faecal occult blood tests with or without immunochemical faecal tests. RESULTS: Total colonoscopy was performed on 151 subjects who prepared both guaiac and immunochemical faecal tests (group 1) and the positive predictive values (PPV) were also compared to those of 162 subjects undergoing colonoscopy for positive guaiac faecal occult blood tests (group 2). In group 1, comparative sensitivity, specificity, and PPVs for significant neoplasia with guaiac faecal occult blood test were 75%, 34%, and 12% (PPV, 18% for group 2) and with immunochemical faecal test were 75%, 94% and 60% (P < 0.01 for specificity). The number of colonoscopy examinations needed to detect a significant neoplasm because of positive faecal occult blood tests was six to eight with HOS and two with OC-MICRO at 21-31% the cost of evaluating a positive guaiac faecal occult blood test. CONCLUSION: An immunochemical faecal test maintains the high sensitivity of guaiac faecal occult blood test, but significantly reduces the colonoscopy burden and screening costs.     

Respiratory diseases and pesticide exposure: a case-control study in Lebanon

STUDY OBJECTIVE: To evaluate the odds of being exposed to pesticides in asthmatic adults. DESIGN: A case-control study was performed in Lebanon. SETTING: People were approached when consulting physicians as outpatients. PATIENTS: Asthmatic patients and non-asthmatic controls in several Lebanese hospitals were interviewed. MAIN RESULTS: The study included 407 subjects from 10 medical centres. Any exposure to pesticides was associated to asthma (OR = 2.11 (1.47 to 3.02); p<10(-4)). Occupational use presented the highest association (OR = 4.98 (1.07 to 23.28); p = 0.02), followed by regional exposure (OR 3.51 (2.11 to 5.85); p<10(-4)). Results were confirmed by multivariate analysis, particularly for regional exposure (OR(a) = 2.78; p = 0.02) and house exposure (OR(a) = 2.17; p = 0.001). CONCLUSIONS: Results are comparable to those found in other studies; especially for occupational exposure. Pesticides toxicological effects may explain chronic respiratory symptoms and asthma associations found with all exposure types. Pesticide exposure was associated with asthma in Lebanese adults.     

Role of mitotic, pro-apoptotic and anti-apoptotic factors in human kidney development

The expression pattern of mitotic Ki-67 and anti-apoptotic bcl-2 proteins, as well as apoptotic caspase-3 and p53 proteins, were investigated in the human mesonephros and metanephros of 5–9 week-old human conceptuses. Apoptotic cells were additionally detected using the terminal deoxynucleotidyl transferase (TdT) nick-end labelling (TUNEL) method. Between the 5th and 7th developmental weeks Ki-67, caspase-3 and TUNEL-positive cells characterized all mesonephric structures, indicating importance of cell proliferation in the growth of the mesonephros and role of apoptosis in nephrogenesis. From the 7th week on, p53 and bcl-2 positive cells appeared in the mesonephros as well. Regressive changes in the mesonephros could be regulated by activation of p53, while bcl-2 could contribute to selective survival of some tubules giving rise to adult structures. In the early human metanephros (5–7 weeks), Ki-67 positive cells characterized all metanephric structures, indicating a role of cell proliferation in branching of the ureteric bud and in nephron formation. During the same period bcl-2, caspase-3 and TUNEL-positive cells were found only in the metanephric mesenchyme and nephrons. Bcl-2 protein probably protected nephrons from apoptosis, while caspase-3 protein controlled cell death in the mesenchyme. At later stages (7–9-weeks), appearance of p53-expressing cells could participate in further morphogenesis of the metanephric collecting system. The factors investigated had a spatially and temporally restricted pattern of appearance in developing kidneys. Changes in that pattern might lead to serious disturbances of kidney formation and function in early childhood.     

Seizure and memory outcome following temporal lobe surgery: selective compared with nonselective approaches for hippocampal sclerosis

OBJECT: The aim of this study was to compare seizure and memory outcome in patients with medically refractory mesial temporal lobe epilepsy due to hippocampal sclerosis (MTLE/HS) treated using an anterior temporal lobectomy (ATL) or a selective amygdalohippocampectomy (SA). METHODS: Surgical outcome data were prospectively collected for 2 to 11 years in 161 consecutive patients with MTLE/ HS. Eighty patients underwent an ATL and 81 an SA. Seizure control achieved with each technique was compared using the Engel classification scheme. Postoperative memory testing was performed in 86 patients (53%). At the last follow up, 72% of the patients who had undergone an ATL (mean follow up 6.7 years) and 71% of those who had undergone an SA (mean follow up 4.5 years) were seizure free (Engle Class IA). Estimated survival in patients in Engel Classes I, IA, and I and II combined did not differ between the two surgical techniques. Preoperatively, 58% of the patients had verbal memory scores one standard deviation (SD) below the normal mean. One third of the patients with preoperative scores in the normal range worsened after surgery, although this outcome was not related to the surgical technique. In contrast, one third of those whose preoperative scores were less than -1 SD experienced improvement after surgery. Nine (18%) of the 50 patients whose left side had been surgically treated improved their verbal memory scores by more than one SD. Seven (78%) of these nine underwent an SA (p = 0.05). CONCLUSIONS: Both ATL and SA can lead to similar favorable seizure control in patients with MTLE/HS. Preliminary data suggest that postoperative verbal memory scores may improve in patients who undergo selective resection of a sclerotic hippocampus in the dominant temporal lobe.     

Cataract surgery after injection of silicone]

Thirty eyes were studied retrospectively, after cataract surgery following intraocular silicone oil injection. Cataract surgery took place before silicone oil removal in 9 eyes, at the same time as silicone oil removal in 2 eyes, and after silicone oil removal in 19 eyes. Extracapsular extraction was performed in 27 eyes, and intracapsular extraction was performed in 3 eyes. A posterior chamber intraocular lens was placed in 14 cases, and an anterior chamber intraocular lens in one case. Capsular fibrosis was observed in 19 cases, and it was treated with YAG laser in 10 eyes during follow-up. Twenty five eyes had a postoperative follow up of 3 to 37 months. Total retinal detachment occurred in 2 eyes.     

Oral tolerance and its relation to food hypersensitivities

The gastrointestinal tract is the largest immunologic organ in the body. It is constantly bombarded by a myriad of dietary proteins. Despite the extent of protein exposure, very few patients have food allergies because of development of oral tolerance to these antigens. Once proteins contact the intestinal surface, they are sampled by different cells and, depending on their characteristics, result in different responses. Antigens might be taken up by Microfold cells overlying Peyer's patches, dendritic cells, or epithelial cells. Different cells of the immune system participate in oral tolerance induction, with regulatory T cells being the most important. Several factors can influence tolerance induction. Some are antigen related, and others are inherent to the host. Disturbances at different steps in the path to oral tolerance have been described in food hypersensitivity. In this review we provide an overview of oral tolerance and cite data related to food hypersensitivity wherever evidence is available.     

Functional expression cloning reveals a central role for the receptor for activated protein kinase C 1 (RACK1) in T cell apoptosis

Mammalian cDNA expression cloning was used to identify novel genes that regulate apoptosis. Using a functional screen, we identified a partial cDNA for the receptor for activated protein kinase C 1 (RACK1) through selection for resistance to phytohemagglutinin and gamma-irradiation. Expression of this partial cDNA in T cell lines using a mammalian expression vector produced an increase in RACK1 expression and resulted in resistance to dexamethasone- and ultraviolet-induced apoptosis. Down-regulation of RACK1 using RNA interference abolished the resistance of the transfected cells to apoptosis. Overexpression of full-length RACK1 also resulted in the suppression of apoptosis mediated by several apoptotic stimuli, and this effect was quantitatively consistent with the effects of the original cDNA isolated on endogenous RACK1 levels. Together, these findings suggest that RACK1 plays an important role in the intracellular signaling pathways that lead to apoptosis in T cells.     

Humoral immune response to p53 correlates with clinical course in colorectal cancer patients during adjuvant chemotherapy

Background and aims Overexpression of p53 protein in malignancies induces an immune response in some cancer patients. We investigated whether production of serum antibodies against p53 (p53-Ab) is associated with pathohistological parameters of colorectal carcinoma and whether p53-Ab can serve as a tumor marker during cancer treatment.Patients and methods Serum samples from 220 colorectal cancer patients during surgery and adjuvant chemotherapy and 42 healthy controls were tested for the presence of p53-Ab by ELISA. Expression of p53 protein in tumors was determined using mouse anti-human p53-Ab.Results Serum p53-Ab were detected in 18% of patients while all controls were negative. A strong correlation between p53-Ab production and p53 protein expression was observed: 70% of p53-Ab positive cases had tumors positive for p53 vs. 52% of p53-Ab negative cases. There was also a significant predominance of p53-Ab positive cases in Dukes stages B and C over stage A. Although surgery alone reduced p53-Ab levels, decreases in p53-Ab titer became significant midterm through chemotherapy compared to both pre- and postoperative values and remained decreased until the completion of treatment.Conclusion The presence of p53-Ab in sera of patients with colorectal cancer indicates tumors in more advanced histopathologic stages (Dukes B, C). Due to low sensitivity (18%) p53-Ab are not recommendable as a preoperative marker for colorectal cancer. However, due to high specificity (100%), their monitoring after surgery and adjuvant chemotherapy has potential for early diagnosis of tumor relapse in p53-Ab positive cases.     

Influence of predisposing, enabling, and health care need variables on the use of dental health services among Mexican adolescents from a semi-rural location

Objective: The purpose of this study was to quantify the influence of some of the predisposing, enabling, and healthcare need variables on dental health services utilization (DHSU) among Mexican adolescents. Material and methods: This is a cross-sectional analytical study including 1,538 Mexican teenagers 12 and 15 years of age. The dependent variable was DHSU in the previous 12 months. Data were collected through a questionnaire and included demographic, socioeconomic, and behavioral factors. The study included an oral examination. The analysis included nonparametric statistics and a logistic regression model. Results: Of the 1,538 adolescents, 688 were 12 years old and 850 were 15 years old. Girls accounted for 49.9%. The prevalence of DHSU was 15%. In the final model we found that having moved at least once from the community in which the child was born was associated with DHSU (OR: 1.24; 95% CI: 1.10-1.40; p > 0.05), just as it was observed for purchasing purified water for home consumption instead of relying on piped water supplies (OR: 1.52; 95% CI: 1.03-2.25), higher educational attainment of the mother (OR: 1.39; 95% CI: 1.02-1.91) and of the father (OR: 1.87; 95% CI: 1.09-3.19). Having more sound teeth (OR: 0.96; 95% CI: 0.94-0.98), and having at least one tooth with caries (OR: 1.10; 95% CI: 1.01-1.18) were also associated with DHSU (p > 0.05). Conclusion: The percentage of subjects with DHSU in the prior 12 months was low compared with other studies. Our identification of the variables associated with DHSU (often surrogates of socioeconomic position) indicated the existence of oral health inequalities and the need to develop strategies to reduce the gaps identified.