Bacteriuria and colonization of double-pigtail ureteral stents: long-term experience with 237 patients

We prospectively studied 266 patients with indwelling double-pigtail ureteral stents to determine the incidence of stent colonization and associated bacteriuria. A urine culture was obtained just prior to stent insertion and was repeated at the time of its removal. The stent itself was also cultured. Of the 237 evaluable patients, 71 (29.9%) developed bacteriuria. Of the 237 stents, 161 (67.9%) became colonized with microorganisms. Pseudomonas aeruginosa was the most common pathogen isolated from the urine and the stents. Stents in female patients had a higher rate of colonization than those used in males (74.4% v 66.5%). The longer the duration of stenting, the higher was the rate of colonization (58.6% for stents left for < 1 month v 75.1% for those left for > 3 months). The rate of colonization according to catheter type was as follows: C-flex 55.5%, silicone 62.6%, urethane 100%, and Urosoft 56%. Long-term ureteric stenting is associated with a high rate of bacteriuria and stent colonization. The duration of stenting and the type of stent influence the results. We recommend that patients with double-J ureteral stents who could be at risk from bacteremia be covered by appropriate antibiotics, and the stents should be kept indwelling for the shortest possible time. If a patient with a stent develops symptomatic infection, an antibiotic should be started that covers the Pseudomonas species.     

Chemotherapy of gastrointestinal carcinomas and non-small-cell pulmonary carcinoma: a controversy

Patients with metastatic gastrointestinal cancers and metastatic non-small cell lung cancer present an important challenge in medical oncology and palliative care. Symptoms caused by tumor progression should undoubtedly be treated. The management of asymptomatic patients, however, is still controversial. A clinical decision on whether an asymptomatic patient should be treated with chemotherapy at an early or at a late stage in the evolution of the disease must often be reached on an individual basis. Ongoing clinical research to improve treatment results is still urgently needed. Research programs should aim at (a) evaluating new drugs and (b) testing new multi-modal treatment strategies.     

A comparative study of palatal height in a Saudi and Egyptian population

The present study constitutes an attempt to compare normal traits for palatal height and width at different stages of dentition development of two ethnic groups of the Middle East. The observations were obtained from 346 randomly selected normal subjects, 188 Saudis and 158 Egyptians. The stone models were divided into three categories in both groups--primary, mixed and permanent dentitions. Palatal index values were calculated at two levels. Vernier calipers were used to measure the palatal width. Palatal depth was measured by profile Gauge by Vitrex. The results of this study demonstrate no significant difference between ethnic groups at levels 1 and 2 in relation to the palatal height, width and index. For both groups, palatal index increased significantly from the primary to mixed and permanent dentition at level 1. At level 2, palatal index and height showed decreases in measurement in the mixed dentition compared with the primary and the permanent dentitions. Subjective assessment of the palatal height correlated with palatal index. The casts were then labelled so that the shallow group had the smallest palatal index followed by the normal and the deep group had the largest palatal index. The results contribute to the information available on the development of palatal shape within two Middle Eastern populations. Knowledge of the normal range in shape can act as a baseline for studies of certain oral developmental abnormalities.     

Prenatal diagnosis of holoprosencephaly. A series of twelve cases

OBJECTIVE OF THE STUDY: To determine the prenatal ultrasound criteria of holoprosencephaly and their correlation with embryogenesis. MATERIAL AND METHODS: We report 12 cases of holoprosencephaly that have been discovered between January 1990 and June 1996 (eleven alobar holoprosencephalies and one semilobar holoprosencephaly) at La Grave Hospital, Toulouse. RESULTS: In all cases, severe facial anomalies have been (cyclopia, cebocephaly or ethmocephaly). Prenatal ultrasound diagnosis was based on the association of brain anomalies (wide monoventricular cavity, thalami fusion, lacking of median structures) and facial dysmorphia (hypotelorism, orbital anomalies, median cleft lip ...). Finding microcephaly was a frequent sign of holoprosencephaly (64% of all cases). Chromosomal abnormalities have been found in 36% of the fetuses (Trisomy 13 is the most common). All patients underwent therapeutic abortions. CONCLUSION: Transvaginal sonography diagnosis can be made around the 14th to 16th week amenorrhea. An early diagnosis allows an easier pregnancy termination, when such severe anomalies are found. In order to provide genetic counseling, a cytogenetic study of the fetus is necessary.     

Increased 3-nitrotyrosine in both sporadic and familial amyotrophic lateral sclerosis

The pathogenesis of neuronal degeneration in both sporadic and familial amyotrophic lateral sclerosis (ALS) associated with mutations in superoxide dismutase may involve oxidative stress. A leading candidate as a mediator of oxidative stress is peroxynitrite, which is formed by the reaction of superoxide with nitric oxide. 3-Nitrotyrosine is a relatively specific marker for oxidative damage mediated by peroxynitrite. In the present study, biochemical measurements showed increased concentrations of 3-nitrotyrosine and 3-nitro-4-hydroxyphenylacetic acid in the lumbar and thoracic spinal cord of ALS patients. Increased 3-nitrotyrosine immunoreactivity was observed in motor neurons of both sporadic and familial ALS patients. Neurologic control patients with cerebral ischemia also showed increased 3-nitrotyrosine immunoreactivity. These findings suggest that peroxynitrite-mediated oxidative damage may play a role in the pathogenesis of both sporadic and familial ALS.     

Imaging of lipoma of the pericardium

Pericardial lipoma is a benign mediastinal tumours. Its location into the pericardial space is well demonstrated by MRI or CT if pericardium is visible; otherwise, diagnosis is evoked on the displacement or compression of cardiac cavities.     

Glutamine extraction by the gut is reduced in depleted [corrected] patients with gastrointestinal cancer

In order to investigate the expression of MUC5AC mucin in normal gastric mucosa and gastric carcinomas, we produced 3 monoclonal antibodies (MAbs) using a MUC5AC synthetic peptide. The immunohistochemical study was performed using one of these MAbs (CLH2) which reacted with the different designs of peptides based on the MUC5AC tandem repeat and with native and deglycosylated mucin extracted from gastric tissues. CLH2 immunoreactivity was restricted to foveolar and mucopeptic neck cells in normal gastric mucosa. No reactivity was observed in type-I intestinal metaplasia. Out of 66 gastric carcinomas, 42 (63.6%) expressed MUC5AC. Most diffuse carcinomas were positive (83.3%), whereas only 59.3% of intestinal and 40.0% of atypical carcinomas expressed MUC5AC (p < 0.05). Gastric carcinomas with mixed pattern showed immunoreactivity in diffuse areas and decreased immunoreactivity in intestinal areas. Every early gastric carcinoma expressed MUC5AC, in contrast to 58.6% of advanced carcinomas (p < 0.05). A trend toward decreased immunoreactivity was observed in deep areas of advanced carcinomas in comparison with the respective superficial areas. Taking together the specific staining of foveolar and mucopeptic neck cells and the absence of immunoreactivity in intestinal metaplasia, we conclude that MUC5AC expression may be used as a marker of gastric differentiation. This assumption is further supported by the finding of MUC5AC immunoreactivity in most diffuse carcinomas, which usually display morphologic and histochemical signs of gastric differentiation. The expression of MUC5AC in early gastric carcinomas, regardless of their histologic type, suggests that all gastric carcinomas retain at least some cells with a gastric phenotype during the first steps of neoplastic development.     

Guanylin, an endogenous ligand for C-type guanylate cyclase, is produced by goblet cells in the rat intestine

BACKGROUND & AIMS: Guanylin activates an intestinal guanylate cyclase (GCC) and stimulates electrolyte movement across the gut epithelium. Cells expressing guanylin messenger RNA have been localized to the epithelial cell layer of the intestine; however, the identity of the guanylin-producing cells has not been determined. The aim of this study was to identify cells that express guanylin in the rat intestine. METHODS: Antibodies were raised against defined proguanylin epitopes, evaluated by Western blotting, and used for immunoperoxidase histochemistry. RESULTS: Guanylin-like immunoreactivity was localized to a subset of goblet cells. In the small intestine, most, perhaps all, goblet cells in the villi were immunopositive, as were some goblet cells in upper crypts; however, goblet cells deep within crypts were unlabeled. In the colon, goblet cells clustered in the necks and around the openings of crypts were immunopositive, whereas (as in the small intestine) goblet cells in deeper crypt regions were unlabeled. In some animals, immunoreactive columnar epithelial cells were also observed in the colon (although such cells were not apparent in the small intestine). Relative labeling of columnar cells varied from animal to animal. CONCLUSIONS: Guanylin is expressed in mature goblet cells. If secreted in conjunction with mucin, it could play a role in the hydration of mucus.     

5-Fluorouracil-resistant colonic tumors are highly responsive to sodium butyrate/interleukin-2 bitherapy in rats

Advanced colorectal cancer is generally refractory to 5-fluorouracil (5-FU) chemotherapy. This is linked to the emergence of resistant cell populations, probably due to a selection process. The identification of molecular markers and the improvement of alternative therapies thus remain important. We have used as an experimental model a rat colon cancer cell line (PROb), which exhibits features similar to those of the human situation. 5-FU treatment of rats bearing PROb tumors enhanced their survival but did not lead to cure. A PROb 5-FU-resistant subline (PRObR1) was obtained by continuous in vitro exposure to 5-FU. Resistance to 5-FU was accompanied by a 2-fold increase in thymidylate synthase activity and a substantially higher incorporation of thymidine in the presence of 5-FU, compared with parental PROb cells. Unexpectedly, in syngeneic rats, PRObR1 tumors exhibited delayed growth when compared with parental PROb tumors. This was ascribed to an increased sensitivity of PRObR1 cells to host immune response since no growth delay was observed in immunocompromised nude mice and since there was no detectable difference in proliferation rates between PROb and PRObR1 cells. 5-FU treatment was inefficient in prolonging the survival of rats bearing PRObR1 tumors. In contrast, an immunotherapeutic protocol combining sodium butyrate and recombinant interleukin-2 (NaBut/rIL-2) cured 80% of the rats bearing established PRObR1 tumors. Our results suggest that NaBut/rIL-2 treatment is efficient against 5-FU-chemoresistant rat colon cancer.