Pneumonia in stroke patients with oropharyngeal dysphagia: a six-month follow-up study

The aim of the study was to estimate the frequency of pneumonia and to determine the risk factors for this complication in poststroke patients with oropharyngeal dysphagia (OD). We prospectively followed up 67 patients (mean age 72.9+/-12.2 years) in the first 6 months after stroke, during which time we recorded gender, stroke side, type of lesion, diabetes, history of chronic obstructive pulmonary disease (COPD), smoking, level of consciousness, functional outcome, dietary history, occurrence of chest infection, and death. Degree of OD and presence/absence of reflex cough was assessed by Fiberoptic Endoscopic Evaluation of Swallowing. Sixty patients showed complete recovery of prestroke swallowing; 9 (13.4% IC 95%=5-20%) developed pneumonia, two of whom died. The first episode of pneumonia occurred in all nine patients within the first month after stroke onset. The pneumonia was associated with absence of reflex cough after swallow, COPD, and severe impairment of consciousness and poor functional outcome.     

Validity of the Ottawa rules for X-ray request in ankle and midfoot injuries in paediatric patients

The aim of the study was to analyse the validity of the Ottawa rules for the X-ray request in A&E for ankle and midfoot injuries in paediatric patients. An observational and prospective study was carried out applying the Ottawa rules to patients attending the Accident and Emergency (A&E) department in Toledo, due to ankle or midfoot injuries from the 1 July 2003 to the 1 February 2004. A total number of 190 patients were included in this study and 29 of these were found to have a fracture. Assessment of the ankle and/or midfoot injuries was made by the orthopaedic junior or senior staff, applying the Ottawa rules. An X-ray request was made for every patient seen, regardless of the Ottawa rules results. The results showed that the sensitivity for the Ottawa rules was 96.9% (95% CI, 94–99.1%). The negative predictive value was 96.6% (95% CI, 96.5–100.1%). The specificity was 36% (95% CI, 29.2–42.9%). The positive predictive value was 21.4% (95% CI, 15.5–27.2%). It can be concluded that The Ottawa rules make up valid instrument for the decision of X-ray request in patients under the age of 18 with ankle and/or midfoot injuries.     

Epoxides metabolically produced from some known carcinogens and from some clinically used drugs. I. Differences in mutagenicity

The epoxide metabolites of two clinically used drugs and an experimental psychotropic agent, carbamazepine 10,11-oxide, cyproheptadine 10,11-oxide and cyclobenzaprine 10,11-oxide, were fully devoid of any mutagenic activity under conditions where K-region-epoxide metabolites of some known carcinogens, such as benzo (a)pyrene, proved to be potent frameshift mutational agents for Salmonella typhimurium TA 1537 and TA 1538. All epoxides tested were non-mutagenic for TA 1535, designed to detect substitution mutations. The 10,11-epoxides of the three drugs, carbamazepine, cyproheptadine and cyclobenzaprine, were not cytotoxic to any of the bacterial tester strains used, precluding that mutagenicity might have been overshadowed by cytotoxicity. When the mutagen precursor, benzo (a)pyrene, was incubated together with TA 1537 and a mammalian microsomal preparation in the presence of a system generating the co-factor necessary for mono-oxygenase activity, activation to mutagenic species was observed which was dramatically increased in the presence of a potent epoxide hydratase inhibitor, 1,1,1-trichloropropene 2,3-oxide, suggesting epoxide (s) as the (or one of the) mutagenically active species metabolically produced in situ. None of these effects was observed with the three medical drugs. Moreover, the observation that the alkene oxide 4-phenylstyrene 7,8-oxide is mutagenic to the two strains TA 1537 and TA 1538 but the K-region arene oxide derived from 7,12-dimethylbenz (a) anthracene is inactive for the latter strain indicates that epoxidation of an aromatic double bond of a polycyclic hydrocarbon is neither a necessary nor a satisfying condition for frameshift mutagenesis to occur.     

Argentine hemorrhagic fever: a primate model.

Experimental Junin virus infection of a New World primate, Callithrix jacchus, was evaluated. The virus produced anorexia, loss of weight, thrombocytopenia, leukopenia, and hemorrhagic and neurological symptoms and terminated in death. Virus was recovered from urine, blood samples and all tissues taken at autopsy. These preliminary observations show that several aspects of the experimental disease in C. jacchus are quite similar to severe natural Argentine hemorrhagic fever of man.     

Serum thyroglobulin levels in patients with well-differentiated thyroid cancer during suppression therapy: study on 429 patients

Serum thyroglobulin (Tg) was measured in 429 patients with well-differentiated thyroid carcinoma, during thyroid hormone suppression therapy. 324 patients out of 429 were considered free of disease; 44 had only remnants in the thyroid bed; 61 had metastases, of them 40 were detected by TBS and 21 were nonfunctioning and were detected by other diagnostic procedures. Tg was measured by a RIA method in 257 patients and by an IRMA method in 277 patients. The correlation between the two methods was very good (r=0.914) for values higher than 25 ng/ml with the RIA method. The cut-off limit to distinguish pathological from nonpathological values was considered the mean value found in the patients free of disease plus 2SD. The cut-off limit for the RIA method was 24.2 ng/ml and 3.0 ng/ml for the IRMA method. Of patients with high Tg levels 92% had metastases, either nodal or distant; only 8% had remnants in the thyroid bed. Tg levels were high in 80% of the patients with metastases, all but two of the patients with metastases and low Tg levels had nodal metastases. Moreover, Tg levels were high in 76% of the patients with metastases unable to take up radioidine. In conclusion: patients with low levels of serum Tg during suppression therapy have a high probability of being free of disease, even though the presence of tumors cannot be excluded. On the other hand a value greater than the cut-off limit suggests the presence of metastases despite a negative scan.     

Pregnancy after high therapeutic doses of iodine-131 in differentiated thyroid cancer: potential risks and recommendations

Seventy female patients who had been treated with high doses of iodine-131 for differentiated thyroid cancer (DTC) and who had a subsequent pregnancy were evaluated. The total ¹³¹I dose ranged from 1.85 to 16.55 GBq (mean±SD=4.39±25.20 GBq). Age at first therapy ranged from 15 to 36 years (mean±SD = 24.3±5.0 years) and the interval from ¹³¹I therapy topregnancy varied from 2to 10 years (mean±SD = 5.3±2.8 years). The estimated radiation doseto the gonads ranged from 10 to 63 cGy (mean±SD = 24.0±13.5 eGy). All patients were treated with l-thyroxine at doses capable of suppressing thyroid-stimulating hormone. Seventy-three children were followed-up and seven pregnancies are still in progress. One child was affected by Fallot's trilogy and three had a low birth weight though with subsequent normal growth; the others were healthy with subsequent normal growth. No newborn with clinical or biochemical thyroid dysfunctions was found. Two spontaneous abortions during the second month of pregnancy were recorded. One of two patients in question subsequently had two healthy children. On the basis of these data, previous administration of high ¹³¹I doses does not appear to be a valid reason for dissuading young female DTC patients from considering pregnancy. However, patients should be advised to avoid pregnancy after ¹³¹I administration for a period sufficient to ensure complete elimination of the radionuclide and to permit confirmation of complete disease remission, i.e. at least 1 year in our opinion.     

Antigen unmasking on formalin-fixed,paraffin-embedded tissue sections

Enzymatic and non-enzymatic treatments for antigen unmasking on formalin-fixed, paraffin-embedded, dewaxed sections were optimized and compared by the use of a panel of antibodies of diagnostic relevance (anti-cytokeratins, vimentin. S-100. T- and B-cell receptors, Ki-67/MIB 1, muscle actin). Non-enzymatic unmasking was obtained by boiling the slides in a microwave oven in 0.01 M salt solution (pH 6) or in 6 M urea. Trypsin or pronase digestion was used for comparison and found to be necessary for some of the reagents. The investigation was then extended to 256 antibodies; the epitopic amino acid sequence was known for 48 of them. We found that enzymatic and non-enzymatic antigen unmasking are not dependent on the epitope sequence, but some antigens benefit selectively from one treatment but not from the other. Denaturation of proteins is the likely mechanism which leads to immunodetection on microwave oven-boiled slides; this suggestion is supported by the use of denaturating solutions and by the observation that endogenous enzymes were inactivated and a few antigens were no longer immunodetectable after boiling. Non-enzymatic methods for antigen unmasking are a powerful new tool for broadening the use of antibodies for immunostaining formalin-fixed, paraffin-embedded sections and should be used in parallel with the traditional enzymatic methods.     

Effect of lysosomotropic agents on the foot-and-mouth disease virus replication

The effect of two lysosomotropic agents, NH₄Cl and chloroquine, on the foot-and-mouth disease virus (FMDV) replicative cycle was studied. When the drugs were present throughout the viral replicative cycle, an important inhibition of viral RNA synthesis and virus production was detected. The inhibition of viral RNA synthesis was maximal when the drugs were present from 30 min before virus infection up to 30 min after that. Otherwise, if the agents were added once the viral synthesis has started (150 min p.i.) the effect was not evident. The agents neither exerted direct virucidal effects, nor did they affect viral adsorption. The results indicate that the lysosomotropic agents affect preferentially an early intracellular event during the viral infective cycle.