Comparisons of activity measurements with radionuclide calibrators

The correct administration to a patient of the prescribed activity of a radiopharmaceutical is an important factor to ensure the confidence in the diagnosis or the therapeutic efficiency, while at the same time keeping the unnecessary human exposure as low as possible. Comparisons of activity measurements for 131I, 201Tl and 99mTc with radionuclide calibrators were organized the first time in Cuba during 2002 with the aim of obtaining information about the quality of administration of radiopharmaceuticals. Ten Cuban nuclear medicine departments and the laboratories involved in the production of these kinds of compounds participated in the comparison runs. The results presented in this paper facilitated the identification of several problems and initiated corrective actions. In addition, they indicate the necessity of establishing Quality Systems in nuclear medicine in Cuba.

Sandpile formation by revolving rivers

Experimental observation of a new mechanism of sandpile formation is reported. As a steady stream of dry sand is poured onto a horizontal surface, a pile forms which has a thin river of sand on one side flowing from the apex of the pile to the edge of its base. The river rotates about the pile, depositing a new layer of sand with each revolution, thereby causing the pile to grow. For small piles the river is steady and the pile formed is smooth. For larger piles, the river becomes intermittent and the surface of the pile becomes undulating. The essential features of the system that produce the phenomenon are discussed, and the robustness of the phenomena is demonstrated with experiments using different boundary conditions and sands.

[Radiologic evaluation of idiopathic congenital clubfoot and its clinical correlation in Codivilla's surgical technique]

Thirty-seven patients (52 idiopathic clubfeet) were treated with Codivilla's technique between 1971 and 1985. Radiological measurements and clinical evaluation before and after surgery were performed; a correlation was carried out between these evaluations and personal satisfaction. The results were rated as follows: poor in 4 feet (7.7%), fair in 18 feet (34.6%), good in 24 feet (46.2%) and excellent in 6 feet (11.5%) with a total percentage of satisfactory results amounting to 57.7%. Our conclusion is that when the indications are properly established, Codivilla's technique is a good procedure to correct clubfoot.

Cough reflex testing with inhaled capsaicin in the study of chronic cough

OBJECTIVES

To assess the utility of capsaicin test in the differential diagnosis of non-productive causes of chronic cough and to examine the effects of treatment on this reflex.

PARTICIPANTS

86 healthy volunteers and 101 patients with chronic cough: asthma (n: 54) gastroesophageal reflux (n: 35) and post-nasal drip syndrome (n: 12).

DESIGN

Prospective intervention trial. Spirometry, bronchoprovocation test with histamine (PC20), and cough challenge with ascending concentrations of capsaicin (0.49-500 microM) were initially performed in all subjects. Patients were treated for 3 months according to the origin of the cough. Concentrations that elicited two (C2) and five or more coughs (C5) were determined before and after treatment.

RESULTS

In healthy subjects, cough sensitivity to capsaicin was not influenced by gender or smoking status; however, women with chronic cough were more sensitive to cough challenge than men. C2 and C5 were significantly lower in patients with asthma or gastroesophageal reflux than in post-nasal drip syndrome. No significant correlation was observed between the capsaicin cough threshold and PC20. Cough sensitivity did not improve significantly in most patients with asthma or gastroesophageal reflux despite adequate medical treatment during 3 months. Discriminative value of capsaicin test to differentiate healthy subjects from patients with asthma or reflux was poor.

CONCLUSIONS

Cough sensitivity to inhaled capsaicin is a safe and reproducible tool in the study of chronic cough. However, its usefulness for the management and differential diagnosis is limited.

Development of a rapid polymerase chain reaction-ELISA assay using polystyrene beads for the detection of Toxoplasma gondii DNA

AIMS

To develop a rapid colourimetric assay for the detection of Toxoplasma gondii DNA using polystyrene beads as solid support.

METHODS AND RESULTS

A nested-polymerase chain reaction (PCR)-ELISA assay for the detection of T. gondii DNA was standardized by optimizing the hybridization time and probe concentration. Its detection threshold was then determined and compared with Southern blotting hybridization. These were found to be equivalent, but the PCR-ELISA-beads test is easier to perform and the turnaround time is much shorter than with Southern blot.

CONCLUSIONS

The PCR-ELISA-beads assay is a valuable tool for the detection of T. gondii DNA.

SIGNIFICANCE AND THE IMPACT OF THE STUDY

Our results demonstrate that this PCR-ELISA assay, using polystyrene beads, can be used as a routine diagnostic test for the detection of T. gondii in clinical laboratories.

[Progressive cranial neuropathy due to perineural spread of a facial squamous cell carcinoma]

The paper aims to present the case of a progressive and unilateral cranial polyneuropathy due to perineural spread of cutaneous squamous cell carcinoma. This is a case of a 73 year old man with a history of squamous cell carcinoma in the right temporal region that was removed in 1992. In May 2000 he first presented pain and numbness in the distribution of the first branch of right trigeminal nerve and weakness of the ipsilateral frontal muscle. Later on he presented right ophthalmoplegia, and damage of lower cranial nerves, leading to dysphagia and respiratory distress. He was admitted in March 2001 for a gastrostomy for feeding, when ataxia and recurrence of the right temporal lesion ensued. After three examinations with MRI, the fourth study showed meningeal carcinomatous and a metastatic lesion in the brainstem. Histopathologic examination demonstrated dermal and perineural invasion by squamous cell carcinoma. The necropsy also showed meningeal, perineural and endoneural infiltration of atypical epidermal cells and a pons mass composed of the same cells. We conclude that the perineural spread of the cutaneous carcinoma is an exceptional cause of cranial neuropathy, however it must be ruled out in patients with progressive and unilateral cranial neuropathy. In these cases, when no radiological abnormalities are noted, a biopsy may be performed on the peripheral branches of the cranial nerve to confirm the diagnosis.

Rapid urinary antigen test for diagnosis of pneumococcal community-acquired pneumonia in adults

Streptococcus pneumoniae is suspected to cause an important proportion of community-acquired pneumonia (CAP) whose aetiology cannot be detected with conventional tests. In this study, the authors evaluated the diagnostic yield of a new immunochromatographic membrane test (ICT) for the detection of the S. pneumoniae antigen in the urine of patients admitted with diagnosed CAP. ICT was performed in unconcentrated and concentrated urine from all the patients. ICT was repeated 1 month after discharge in a group initially testing positive. The authors also studied the ICT in clinically stable human immunodeficiency virus type 1 (HIV1)-infected patients. S. pneumoniae antigen was detected in all of the 68 (100%) patients tested with definitive pneumococcal pneumonia. In five of these cases ICT was only positive when it had been performed on the patients. The S. pneumoniae antigen was also detected in 36 (69.2%) of 52 patients with probable pneumococcal pneumonia and in 50 of 277 (18%) patients without pneumococcal pneumonia. ICT remained positive in 16 (69.5%) of 23 patients, 1 month after hospital discharge. Nasopharyngeal colonisation with S. pneumoniae was detected in 8 (12%) of 68 clinically stable HIV1 infected patients, but none tested ICT positive. The Binax NOW it immunochromatographic membrane test is a rapid, sensitive and specific test for detecting pneumococcal community-acquired pneumonia in adults. The test may remain positive for several weeks after pneumococcal pneumonia.

Comparison of the sodium dodecyl sulfate-sodium hydroxide specimen processing method with the C18-carboxypropylbetaine specimen processing method using the MB/BacT liquid culture system

The ability of physicians to diagnose tuberculosis is impacted by the use of smear and culture techniques combined with specimen processing methods. The objective of this study was to evaluate the effects of specimen processing on smear and culture sensitivity by comparing the specimen processing method that uses C(18)-carboxypropylbetaine with the method that combines sodium dodecyl sulfate and sodium hydroxide. A total of 1,201 specimens were entered into this study. Specimens were split approximately equally such that one-half of each specimen was processed with sodium dodecyl sulfate-sodium hydroxide, while the other half was processed with C(18)-carboxypropylbetaine. All sediments were subjected to acid-fast staining and then analyzed using the MB/BacT liquid culture system (bioMérieux, France) and solid media. The sensitivity of smear following processing with sodium dodecyl sulfate-sodium hydroxide and C(18)-carboxypropylbetaine was 61.2% and 58.6% (P>0.05), respectively, while the specificities were identical (99.7%). The sensitivity of culture was 84.2% and 96.1% (P<0.05), respectively. The time to detection in the MB/BacT liquid culture system was 13.2+/-5.6 and 15.0+/-8.8 days (P>0.05), respectively, and 20.0+/-7.6 and 15.7+/-8.9 days (P<0.05), respectively, on solid media. The contamination rates in the MB/BacT system were 0.8% and 8.7%, respectively, whereas the contamination rates on solid media were 2.6% and 4.3%, respectively. C(18)-carboxypropylbetaine specimen processing was less labor-intensive than sodium dodecyl sulfate-sodium hydroxide processing and improved the ability of laboratory staff to detect the presence of mycobacteria by culture.

Threonines at position 174 and 235 of the angiotensinogen polypeptide chain are related to familial history of hypertension in a Spanish-Mediterranean population

This study investigates the association between the allelic distribution of two polymorphisms of the angiotensinogen (AGT) gene (T174M and M235T in the polypeptide chain) and blood pressure (BP) in a Mediterranean population in the south-west of Europe. The sample consists of 1322 participants from urban and rural areas, from the province of Albacete (218,462 inhabitants), located in the south-east of Spain. The subsample of this study, adjusted by age (over 18 years old) and sex, consists of 401 individuals. A case-control study is conducted which analyses 205 individuals from the group with the highest BP (fifth quintile) and 196 from the group with the lowest BP (first quintile). In addition, a comparative and associated analysis of these polymorphisms with BP level and family history of hypertension is carried out. The T174 allele proved to be more common in the fifth quintile group, although not statistically so. When the presence of threonine was analysed in both polymorphism positions (174 and 235), the TTTT genotype was found to be more common in the fifth quintile than in the first quintile. Moreover, the TTTT genotype was significantly more common in individuals with a family history of hypertension, indicating that it could be considered a predisposing factor to high BP in individuals from such families. In addition, the T174M-T235T genotype was more common in the first quintile group, and showed significant association (P=0.05) with the group that had no family history of hypertension.

Analysis of NLS and rRNA binding motifs in the L25 ribosomal protein from Leishmania (viannia) braziliensis: investigation of its diagnostic capabilities

A cDNA clone codifying ribosomal protein L25 was isolated from a Leishmania braziliensis cDNA gene library. The alignment of the amino acid sequence deduced from this gene with other proteins revealed that this protein is related to the L23/25 rihosomal protein family. This is so because this protein shows, in its C-terminal end, the rRNA binding domains characteristic of these proteins and at the N-terminal end the NLS sequence necessary for its entry into the nucleus. Southern blot analysis showed 2 copies of gene L25 per genome arranged in tandem position and pointing in the same direction. Northern blot analysis showed that this gene is transcribed in 2 mRNAs when parasite promastigotes are in the logarithmic phase. In order to analyse the antigenic properties of L. braziliensis RPL25, it was purified as a recombinant protein and ELISA-tested against cutaneous, mucocutaneous and Chagasic sera. The results indicate that the recombinant RPL25 from L. braziliensis presents a non-specific reaction that disqualifies it for the diagnosis of cutaneous leishmaniasis. In contrast, some of the synthetic peptides derived from its sequence may serve as promising tools for the diagnosis of this disease.

The EORTC QLQ-C30 (version 3.0) Quality of Life questionnaire: validation study for Spain with head and neck cancer patients

The EORTC Quality of Life Study Group has developed a questionnaire for evaluating Quality of Life in international clinical trials: QLQ-C30. The purpose of the present work is to validate the third version of this questionnaire (3.0) for use in Spain. Two hundred and one head and neck cancer patients completed the QLQ-C30 at one or two time points during the treatment and follow-up periods, and a subsample completed the questionnaire on three occasions. Psychometric evaluation of the structure, reliability and validity of the questionnaire was undertaken. The data support the structure and the reliability of the scales. Validity was confirmed in three ways: the interscale correlations are statistically significant and moderate, several scales and items discriminate among groups of patients with different scores on the clinical variables, and some scales reflect significant changes during treatment and the follow-up period. The EORTC QLQ-C30 (version 3.0) is a reliable and valid questionnaire when applied to a sample of Spanish head and neck cancer patients. These results are in line with previous studies.

Cloning and molecular characterization of the cDNA encoding histone H1 from Leishmania braziliensis

The isolation and molecular characterization of the histone H1-encoding gene from Leishmania braziliensis was carried out. The gene is present in the genome as a single copy and transcribed as a polyadenylated transcript of 830 nucleotides. The deduced amino acid sequence has in its central region the DNA binding K-[K/R]-A-A-[A/P] motif, which is repeated in tandem 9 times.

Thermoluminescent response of ZrO2 + PTFE prepared in Mexico to 90Sr/90Y beta particles

Results of studying the thermoluminescent response of undoped ZrO2 + PTFE pellets irradiated with 90Sr/90Y beta particles are presented. Previously, TL characteristics of ZrO2 films doped with rare earths were studied. Phosphor powder was obtained by evaporating a solution of zirconium nitrate in ethanol. In order to stabilise the traps in ZrO2 this phosphor was submitted to different thermal treatments. Optimal thermal treatment consisted in heating at 1100 degrees C for 24 h. With this powder. pressing at room temperature a mixture (2:1) of ZrO2 and polytetrafluoroethylene (PTFE), pellets of 5 mm diameter and 0.8 mm thickness were made. The glow curve of ZrO2 + PTFE pellets exhibited two peaks at 200 and 250 degrees C: its TL response as a function of beta particles dose was linear in the range from 2 to 60 Gy. Repeatability over 10 cycles was 1.8%. Fading at room temperature was 3.8% per month.

Preparation and thermoluminescence properties of aluminium oxide doped with europium

There is little information concerning the use of rare earths as dopants of Al2O3. This paper presents the preparation method and the results of studying the thermoluminescence characteristics of Al2O3:Eu exposed to ultraviolet light. Phosphor powder was obtained by the evaporation method. Optimum dopant concentration was 10% at an evaporation temperature of 700 degrees C. The powder obtained was submitted to thermal treatments at high temperatures in order to stabilise the traps. Diffraction patterns showed amorphous powder up to 500 degrees C; as the temperature was raised crystalline phases of Al2O3 appeared. The photoluminescence spectrum induced by 250 nm UV light exhibited four well defined peaks characteristic of the Eu3+ ion. The glow curve exhibited two peaks at 180 and 350 degrees C. The sensitivity of Al2O3:Eu was 10 times lower than Al2O3:C. The thermoluminescence response was linear from 2.4 to 3000 microJ.cm(-2) of spectral irradiance, and the fading 2% in a month. From these results it can be concluded that Al2O3:Eu has potential as an UV dosemeter.

Polyamine metabolism and glutamate receptor agonists-mediated excitotoxicity in the rat brain

Putrescine (PUT) increases have been seen in a range of models of neuropathological disturbances. The present study was designed to compare the ability of various types of glutamate receptor agonist to promote excitotoxic brain damage and to examine whether a PUT increase is a general marker of excitotoxic brain damage. To that end, we evaluated features of brain damage associated with the excitotoxicity induced by both ionotropic glutamate receptor (iGluR) and metabotropic glutamate receptor (mGluR) agonists in the conscious rat and the changes produced in the regulation of polyamine metabolism. Intracerebroventricular infusion of N-methyl-D-aspartate (NMDA; 80 nmol), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA; 15 nmol), kainic acid (KA; 2.3 nmol), (R,S)-3,5-dihydroxyphenylglycine (3,5-DHPG; 1.5 micromol), and (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD; 2 micromol) produced similar seizure incidences (76-84%) in the rat. The convulsant episodes appeared sooner after iGluR (13-22 min) than after mGluR agonists (50-179 min). Histological analysis of the hippocampus 24 hr after seizures indicated several degrees of excitotoxic injury after equiconvulsive doses of the iGluR and mGluR agonists assayed. The agonists can be placed in the following order, according to the degree of damage they produce: AMPA > 3,5-DHPG approximately KA > NMDA > 1S,3R-ACPD. In the frontal cortex, moderate to low levels of damage were observed after all GluR agonists. Both iGluR- and mGluR-induced seizures produced an overshoot in the hippocampal and cortical PUT concentration, whereas spermidine and spermine levels were similar to control. Moreover, a concurrence of increased PUT levels and brain damage was observed, indicating that PUT is a general marker of excitotoxic brain damage.

Erectile dysfunction in a primary care setting: results of an observational, no-control-group, prospective study with sildenafil under routine conditions of use

In order to assess the effectiveness of sildenafil under routine conditions of use in primary care settings and to evaluate its impact on patient's life satisfaction and partner's satisfaction with treatment for erectile dysfunction (ED), an open, multicentre, observational, prospective study was designed in which 2816 patients were treated with sildenafil for at least 10 weeks. Effectiveness was assessed using the International Index of Erectile Dysfunction (IIEF), life satisfaction was measured with 'Life-satisfaction Check List' (LISAT 8), and EDITS was optionally used to assess the partner's satisfaction with ED therapy. Sildenafil was effective in 86.6% of patients. All dimensions of IIEF significantly increased with sildenafil, particularly erectile domain which overall sample mean score improved was 13.2 points (P < 0.001). The greatest increases in satisfaction with all aspects of life were seen in sex life and relationship with partner dimensions. The patients' partners, answered by a minority of partners, were highly satisfied with the treatment and its rapid action, therefore they were in favour of continuing with same. The adverse events occurring were similar to those seen in clinical research on sildenafil in the premarketing phase. No control group was included in this study.

Pulmonary reactions during treatment with amphotericin B: review of published cases and guidelines for management

Acute respiratory events occasionally have been observed during the infusion of amphotericin B. Herein we analyze the 21 cases that have been reported, including a fatal reaction observed by us. Some useful guidelines are provided that likely will allow treatment to be continued safely for patients who have experienced such reactions.

Adult and nymphs of Microtriatoma trinidadensis (Lent, 1951) (Hemiptera: Reduviidae) caught from peridomestic environment in Bolivia

This is the first report of adult and nymphs (20 nymphs of all stages and 4 adults) of Microtriatoma trinidadensis (Lent 1951) (Hemiptera: Reduviidae: Triatominae) collected in peridomestic environment, in the department of La Paz, Bolivia. These specimens were associated to Rhodnius stali Lent, Jurberg & Galvão 1993. The exceptional finding of M. trinidadensis in peridomestic environment, illustrates the general tendency of triatominae to adapt to human dwellings and dependences.