Experimental design approach for the optimisation of a HPLC-fluorimetric method for the quantitation of the angiotensin II receptor antagonist telmisartan in urine

A high performance liquid chromatographic method with fluorimetric detection has been developed for the quantitation of the angiotensin II receptor antagonist (ARA II) 4-((2-n-propyl-4-methyl-6-(1-methylbenzimidazol-2-yl)-benzimidazol-1-yl)methyl)biphenyl-2-carboxylic acid (telmisartan) in urine, using a Novapak C18 column 3.9 x 150 mm, 4 microm. The mobile phase consisted of a mixture acetonitrile-phosphate buffer (pH 6.0, 5 mM) (45:55, v/v) pumped at a flow rate of 0.5 ml min(-1). Effluent was monitored at excitation and emission wavelengths of 305 and 365 nm, respectively. Separation was carried out at room temperature. Chromatographic variables were optimised by means of experimental design. A clean-up step was used for urine samples consisting of a solid-phase extraction procedure with C8 cartridges and methanol as eluent. This method proved to be accurate (RE from -12 to 6%), precise (intra- and inter-day coefficients of variation (CV) were lower than 8%) and sensitive enough (limit of quantitation (LOQ), ca. 1 microg l(-1)) to be applied to the determination of the active drug in urine samples obtained from hypertensive patients. Concentration levels of telmisartan at different time intervals (from 0 up to 36 h after oral intake) were monitored.

Comparative analysis and clinical value of the expression of metalloproteases and their inhibitors by intratumor stromal fibroblasts and those at the invasive front of breast carcinomas

An immunohistochemical study was performed using tissue arrays and specific antibodies against MMPs -1, -2, -7, -9, -11, -13, -14, and TIMPs -1, -2 and -3. More than 5,000 determinations on cancer specimens from 124 patients with invasive breast cancer were performed at the center of the tumor and the invasive front. Immunostaining for MMPs/TIMPs by fibroblasts was evaluated. To identify specific groups of tumors with distinct expression profiles, the data obtained from both fibroblast populations were analyzed by unsupervised hierarchical cluster analysis. Intratumor stromal fibroblasts more frequently showed expression of MMP-2, -7, and -14, and TIMP-3, but less frequently of MMP-9 than fibroblasts at the invasive front. Multivariate analysis showed that a high profile of MMPs and TIMPs staining in both fibroblast populations was the most potent predictor factor of distant metastases, whereas a low staining profile in fibroblasts was associated with a low risk of metastases.

Sheep pulmonary adenomatosis: characterization of two pathological forms associated with jaagsiekte retrovirus

Pathological and immunohistochemical studies were performed on the lungs of 10 sheep with lesions of "classical" sheep pulmonary adenomatosis (SPA) and six sheep with "atypical" lung tumours. Lung tumour samples and other tissues from the same 16 animals were tested for the presence of jaagsiekte retrovirus (JSRV) by a polymerase chain reaction (PCR) that amplified a portion of the U3 long terminal repeat. The differences in the gross appearance of the classical and atypical forms paralleled the histopathological differences. The latter mainly concerned the stroma of the tumours which in the atypical cases was more heavily infiltrated by inflammatory cells and connective tissue fibres. JSRV major capsid protein was detected immunohistochemically in the epithelial transformed cells of both classical and atypical tumours, but the immune reactivity was slightly milder in atypical SPA. Proviral U3 sequences of JSRV were detected by specific PCR in all the tumour samples. Furthermore, the sequences of amplimers obtained from the two different pathological forms of the tumour were very similar. However, the dissemination of JSRV to other organs was greater in sheep with classical SPA than in those with atypical SPA. The pathological and virological features of these two forms of tumour are compared in an attempt to clarify whether classical and atypical SPA are two separate diseases or different expressions of a single disease spectrum.

Spatial and temporal trends of volatile organic compounds (VOC) in a rural area of northern Spain

Ambient concentrations of volatile organic compounds (VOCs) were measured at 40 rural sampling points in Navarre (northern Spain). Air samples were collected by means of sorbent passive sampling and analyzed by thermal desorption (TD) and gas chromatography/mass-selective detector (GC/MSD). A total of 140 VOCs were identified during the study, which was carried out between May to October 2004 for a total of a 10 biweekly sampling campaigns. Concentrations of benzene, toluene, ethylbenzene, m/p-xylenes, o-xylene (BTEX) and 1,3,5-trimethylbenzene were determined in order to investigate their temporal and spatial distributions. Geostatistical analysis pointed to traffic as the main emission source of these compounds. Supporting this idea, BTEX and nitrogen oxides concentrations were found to be highly significantly correlated (r = 0.495, P = 0.001), whereas a strong negative correlation between BTEX and ozone was also observed (r = -0.355, P = 0.025). The concentrations for the BTEX group were similar to the values that have been previously reported for other rural areas.

Synthesis and antiallergic activity of pyridothienopyrimidines

The synthesis of a series of pyridothienopyrimidines and their evaluation as inhibitors or inducers of the release of histamine from rat mast cells is reported. The activity was measured after immunological stimulation with ovoalbumin and chemical stimulation with polymer 48/80 and the drugs adryamicin and vinorelbine. The experiments were carried out with and without preincubation of the stimulus with the cells before addition of the drug. Several pyridothienopyrimidines show inhibitory IC50 values in the range 2-25 microM, indicating they are up to 100 times more potent than cromoglycate (DSCG) and 10 times greater than Ketotifen. Compound 9l is a potent inhibitor in all the conditions tested and shows IC50 = 9-25 microM. Pyridothienopyrimidines 4l and 9e are very strong inducers of histamine release in the immunological (4l, 170-230%) and chemical (9e, 100-150%) assays, respectively. Compounds 4l and 9i are cytotoxic in vitro (IC50 = 0.1-0.2 microgram/mL) against P-388, A-549, HT-29, and MEL-28 tumor cell lines.

Patient dosimetry in interventional radiology using slow films

A method for the evaluation of patient doses in interventional radiology procedures is presented and discussed. The method requires the analysis of slow non-screen films such as those used in radiotherapy. Dose area product and patient skin dose can be estimated with fair accuracy depending on the interventional procedure type. The agreement between the slow film method and diamentor measurement is better than 5% after the application of appropriate corrections. The cost is reasonable (pounds 5 per film) making it a worthwhile option in patient dosimetry, especially when the X-ray equipment does not include any fixed dose-area measuring device. Additional valuable information which may be applied to optimization of procedures (e.g. irradiated areas, number and types of projections check of appropriate use of beam limiting devices) is achieved by examining the different irradiation fields on the film.

Gastrointestinal complications in liver transplant recipients: MITOS study

INTRODUCTION

Liver transplant recipients frequently suffer gastrointestinal (GI) complications but their prevalence and their influence on quality of life remain unknown.

OBJECTIVE

The objective of this study was to asses the prevalence, impact on quality of life, and management of GI complications in liver transplant recipients.

PATIENTS AND METHODS

This was an epidemiologic, cross-sectional, multicenter study. Four hundred seventeen liver recipients were recruited in 14 centers. A questionnaire was filled for every patient.

RESULTS

The median age of the patients was 55 years. The median time since transplantation was 4.1 +/- 4 years. Whereas 19.2% presented some GI disease before transplantation, 49.4% showed this type of complication after transplantation. Diarrhea was the most prevalent GI complication, and anorexia was the GI disorder that affected patients daily activities the most frequently. GI complications were more frequent among female patients, subjects with pretransplantation hiatal hernia, and those readmitted after transplantation. Of the patients with GI complications, 70.9% received pharmacological treatment (89.7% with gastric protectors). Immunosuppressive therapy was also modified because of GI complications. Immunosuppressive drug dose was reduced in 18.1%, transiently stopped in 3.4%, and definitively stopped in 3.4% of cases. The drug most frequently changed was mycophenolate mofetil: dose reduction, 23.6%; transient withdrawal, 5.7%; and definitive withdrawal, 6.6%.

CONCLUSIONS

The prevalence of GI complications in the liver transplant population was approximately 50%. GI complications showed a significant impact on the quality of life of the patients. They were related to female gender, to pretransplantation GI pathology, and posttransplantation hospital admission. These complications were frequently managed with pharmacological therapy or with changes in immunosuppressive therapy.

Pathology of ovine pulmonary adenocarcinoma

Clinical, gross pathology, histopathology and electron microscopy of the ovine pulmonary adenocarcinoma (OPA, jaagsiekte) either natural or experimentally induced in sheep, goat and moufflon are described. OPA is caused by an oncogenic betaretrovirus,jaagsiekte sheep retrovirus (JSRV). Most natural cases of OPA appear in animals 1-4 years old. There is no evidence of sex or breed susceptibility. Sheep affected by OPA show an afebrile respiratory illness associated with loss of weight. A very characteristic clinical sign is moist rales caused by the accumulation of fluid in the respiratory airways which is discharged from the nostrils when the head is lowered. Gross lesions are confined to the lungs but occasionally thoracic or extrathoracic structures are also affected. Two pathologic forms of OPA are currently recognized, classical and atypical. In classical forms the neoplastic lesions occurs particularly in the cranioventral parts of all lung lobes. They are diffuse or nodular, light grey or light purple in colour. On the cut surface the tumour is moist, and frothy fluid may pour from the airways on slight pressure. Atypical forms tend to be more nodular in both early and advanced tumours. They are pearly white in colour, very hard in consistency, very well demarcated from the surrounding parenchyma and their surface is dry. Histology of the lung sections reveals the presence of several foci of epithelial cell neoplastic proliferation in both alveolar or bronchiolar regions. The tumours, derived from type II pneumocytes and Clara cells, proliferate into mostly papillary but also acinar or occasionally solid growths. The tumour generally shows a benign histological pattern but intra- and extrathoracic metastases have been detected in some cases. Several considerations suggest that the tumour should be classified as an adenocarcinoma of the lung. The histology of atypical OPA is similar to that of the classical disease, with an increase in the stromal reaction accompanying the epithelial proliferations. Pathological features of OPA induced experimentally in sheep, or of OPA in goats and moufflon are similar to those described in sheep. Detailed electron microscopy of tumour material confirms that type II pneumocytes and Clara bronchiolar epithelial cells are the origin of the neoplasia. Also included in this chapter is a description of the morphology of the viral particles associated with OPA.

Helicobacter pylori eradication: proton pump inhibitor vs. ranitidine bismuth citrate plus two antibiotics for 1 week-a meta-analysis of efficacy

OBJECTIVE

To compare the efficacy of proton pump inhibitor vs. ranitidine bismuth citrate (RBC) with two antibiotics for 1 week in Helicobacter pylori eradication.

METHODS

Randomized trials comparing 1-week regimens with (i) proton pump inhibitor plus two antibiotics [clarithromycin (C) and amoxycillin (A) or a nitroimidazole (N)]; or (ii) RBC plus the same antibiotics. Eradication was confirmed by histology or 13C-urea breath test at least 4 weeks after therapy. Data sources included PubMed database and abstracts from congresses until October 1999. Statistical analysis was by meta-analysis combining the odds ratios (OR) of the individual studies in a global OR (Peto method).

RESULTS

Twelve studies met the selection criteria. Nine compared proton pump inhibitor vs. RBC plus C and A, and five compared proton pump inhibitor vs. RBC plus C and N. With RBC, C and A, mean H. pylori eradication efficacy by intention-to-treat analysis (pooled data) was 76.6% (95% CI: 72-81%) and 73.7% (95% CI: 69-78%) with proton pump inhibitor, C and A. The OR for the effect of RBC vs. proton pump inhibitor (plus C and A) on H. pylori eradication was 1.15 (95% CI: 0.8-1.64%). Mean H. pylori eradication with RBC, C and N was 87. 2% (95% CI: 83-91%), and 74.9% (95% CI: 74-84%) with proton pump inhibitor plus these two antibiotics. The OR for the effect of RBC vs. proton pump inhibitor (plus C and N) on H. pylori eradication was 1.76 (95% CI: 1.08-2.85%).

CONCLUSION

RBC and proton pump inhibitor have similar efficacy for H. pylori eradication when given with C and A for 1 week, but RBC seems to have a higher efficacy than proton pump inhibitor when C and N are the co-prescribed antibiotics.

Comparison of the diagnosis of malaria by microscopy, immunochromatography and PCR in endemic areas of Venezuela

Whole blood samples (N = 295) were obtained from different locations in Amazonas and Sucre States, in Venezuela. Malaria was diagnosed by microscopy, OptiMAL and polymerase chain reaction (PCR), with Plasmodium vivax, P. falciparum, and P. malariae being detected when possible. We identified 93 infections, 66 of which were caused by P. vivax, 26 by P. falciparum, and 1 was a mixed infection. No infection caused by P. malariae was detected. The sensitivity and specificity of each diagnostic method were high: 95.7 and 97.9% for microscopy, 87.0 and 97.9% for OptiMAL, and 98.0 and 100% for PCR, respectively. Most samples (72.2%) showed more than 5000 parasites/microL blood. The sensitivity of the diagnosis by microscopy and OptiMAL decreased with lower parasitemia. All samples showing disagreement among the methods were reevaluated, but the first result was used for the calculations. Parasites were detected in the 6 false-negative samples by microscopy after the second examination. The mixed infection was only detected by PCR, while the other methods diagnosed it as P. falciparum (microscopy) or P. vivax (OptiMAL) infection. Most of the false results obtained with the OptiMAL strip were related to the P. falciparum-specific band, including 3 species misdiagnoses, which could be related to the test itself or to genetic variation of the Venezuelan strains. The use of the microscopic method for malaria detection is recommended for its low cost but is very difficult to implement in large scale, population-based studies; thus, we report here more efficient methods suitable for this purpose.

Accelerated extraction for determination of polycyclic aromatic hydrocarbons in marine biota

A rapid and simple method is proposed for determination of polycyclic aromatic hydrocarbons (PAH) in complex matrices such as marine biota. The method uses sonication, by means of an ultrasonic probe, as a new tool for assisted extraction, coupled with reversed-phase liquid chromatography (RP-LC) with fluorescence detection (FL) for determination of 16 US EPA priority PAH. Separation and detection of the 16 PAH were complete in 45 min by RP-LC with a C18 column and acetonitrile-water gradient elution. Multivariate optimisation of the variables affecting extraction (ultrasound radiation amplitude, sonication time, and temperature of the water-bath in which the extraction cell was placed) was conducted. The accuracy of the method was determined by analysis of a certified reference material and comparison of the results obtained with those from another method (microwave-assisted extraction and GC-MS). The new technique avoids the main problems encountered in the determination of PAH in complex matrices such as marine biota, and no clean-up step is necessary. The method was applied to determination of PAH in estuarine biota samples from the Urdaibai estuary (Biscay, Spain).

Jaagsiekte sheep retrovirus can be detected in the peripheral blood during the pre-clinical period of sheep pulmonary adenomatosis

Peripheral blood leukocytes (PBLs) and tissue samples from 36 sheep were examined for jaagsiekte sheep retrovirus (JSRV) by hemi-nested PCR. Animals were classified according to the status of sheep pulmonary adenomatosis (SPA), which was confirmed by pathological examination, as follows: (i) sheep with classical SPA (cSPA, n=10), (ii) sheep with atypical SPA (aSPA, n=6), (iii) non-affected sheep from SPA-affected flocks (in-contact, n=10) and (iv) non-affected sheep from SPA-free flocks (control, n=10). JSRV proviral DNA was detected in the PBLs of 10/10 cSPA, 5/6 aSPA, 4/10 in-contact and 0/10 control sheep. Lung tumours and lymphoid organs were also found to be JSRV-positive. The number of positive PCR results was greater for sheep in the cSPA group than for those in the aSPA and in-contact groups. For the first time, it is concluded that JSRV can be detected in naturally infected sheep before the onset of clinical disease and even before the development of discernible tumours.

Clinical, metabolic and psychological outcomes and treatment costs of a prospective randomized trial based on different educational strategies to improve diabetes care (PRODIACOR)

AIM

To evaluate the effect of system interventions (formalized data collection and 100% coverage of medications and supplies) combined with physician and/or patient education on therapeutic indicators and costs in Type 2 diabetes.

METHODS

This was a randomized 2 × 2 design in public health, social security or private prepaid primary care clinics in Corrientes, Argentina. Thirty-six general practitioners and 468 adults with Type 2 diabetes participated. Patients of nine participating physicians were selected randomly and assigned to one of four structured group education programmes (117 patients each): control (group 1), physician education (group 2), patient education (group 3), and both physician education and patient education (group 4), with identical system interventions in all four groups. Outcome measures included HbA(1c), BMI, blood pressure, fasting glucose, lipid profile, drug consumption, resource use and patient well-being at baseline and every 6 months up to 42 months.

RESULTS

HbA(1c) decreased significantly from 4 mmol/mol to 10 mmol/mol by 42 months (P < 0.05); the largest and more consistent decrease was in the groups where patients and physicians were educated. Blood pressure and triglycerides decreased significantly in all groups; the largest changes were recorded in the combined education group. The World Health Organization-5 Lowe score showed significant improvements, without differences among groups. The lowest treatment cost was seen in the combined education group.

CONCLUSIONS

In a primary care setting, educational interventions combined with comprehensive care coverage resulted in long-term improvement in clinical, metabolic and psychological outcomes at the best cost-effectiveness ratio.

Fetal development of the human tympanic ossicular chain articulations

OBJECTIVES

To obtain further knowledge on the morphogenesis of the articulations in the tympanic ossicular chain in humans.

MATERIAL AND METHODS

In 25 temporal bones of human fetuses the structural development of incudomallear, incudostapedial and stapediovestibular articulations was studied. The chronological ages were between the 7th week (21 mm) and the 29th week (270 mm).

RESULTS AND DISCUSSION

Incudomallear articulation showed diarthrosis and sellar joint characteristics. It showed a homogenous interzone in the 7th week of development, a three-layered interzone in the 8th week, the first cavitation signs in the 9th week and the presence of an articular cavity in the 10th week. The presence of a hyaline cartilage covering articular surfaces was observed starting in the 20th week of development. Incudostapedial articulation showed typical characteristics of a diarthrosis and spheroidal joint with a homogenous interzone at the 7th week, showing similar characteristics for 12 weeks, and completed its cavitation at the 16th week. We observed hyaline cartilage on articular surfaces from 29 weeks. Stapediovestibular articulation showed typical characteristics of syndesmosis. The annular ligament primordium derived from cartilage differentiation, both from stapedial footplate and from the surrounding otic capsule, into mesenchyme and its subsequent transformation into fibrous tissue, reaching definitive characteristics from the 12th week.

NARP-MILS syndrome caused by 8993 T>G mitochondrial DNA mutation: a clinical, genetic and neuropathological study

The 8993 T>G mutation in mitochondrial DNA has been associated with variable syndromes of differing severity ranging from maternally inherited Leigh's syndrome (MILS) to neuropathy, ataxia, retinitis pigmentosa (NARP), depending on the mutation loads in affected patients. We report a kindred with several members in the same generation suffering NARP or Leigh's syndrome due to a 8993 T>G mutation. Post-mortem studies of the brain in one affected member clinically presenting with a neurological disorder intermediate between adult Leigh's syndrome and NARP showed symmetrical lesions of the basal ganglia and brainstem closely resembling those usually described in typical Leigh's syndrome. Analysis of mtDNA in different tissues showed a high proportion of mutant genome in brainstem, cerebral cortex, putamen, cerebellum and thalamus. These observations illustrate the continuum of clinical and neuropathological manifestations associated with the 8993 T>G mutation of the mtDNA.

Reference doses in dental radiodiagnostic facilities

The present work describes an experiment undertaken using thermoluminescent dosemeters to obtain a local reference dose level in orthopantomography, based on patient measurements in 11 dentistry installations. In addition, a critical audit of the dose recommended by the International Atomic Energy Agency for intraoral X-ray diagnostics is performed, based on data gathered from over 300 intraoral X-ray facilities. The provisional local reference levels proposed are 0.7 mGy entrance surface dose at the occipital region for orthopantomography and 3.5 mGy entrance surface dose for intraoral radiology.

Serological markers during dengue 3 primary and secondary infections

BACKGROUND

The detection of the IgM antibody for the dengue virus in serum by ELISA has become one of the most important and useful methods for diagnosis of dengue using a single acute-phase serum sample. Currently, this system is an invaluable tool for the surveillance of dengue fever (DF) and dengue hemorrhagic fever (DHF). The usefulness of other serological markers such as IgA and IgE have been less studied.

OBJECTIVE

To study the IgM, IgA and IgE specific antibody response in dengue 3 infected patients with different clinical picture and type of infection.

STUDY DESIGN

One hundred and twenty-seven serum samples collected on days 5-7 at the onset of fever from clinically and serologically confirmed dengue cases were studied. Forty-two were classified as primary dengue fever cases, 48 as secondary dengue fever cases and 37 as secondary dengue hemorrhagic fever cases. All samples were tested by capture ELISA in order to detect dengue IgM, IgA and IgE antibodies.

RESULTS AND CONCLUSIONS

In this study, significant differences were observed in the IgM, IgA and IgE response between the study groups. High IgA and IgE OD ratios in secondary dengue cases were found. The usefulness of serotype specific IgM antibody detection is also analyzed and discussed. A priority for future dengue research in terms of protection, recovery of infection and immunopathogenesis is to elucidate the role of these immunoglobulins. The cross reactivity response to IgM between dengue virus serotypes in primary and secondary cases should also be more studied.

Transcranial Doppler sonography in fulminant hepatic failure

The clinical course of patients with fulminant hepatic failure (FHF) is often worsened by the presence of cerebral edema and endocranial hypertension. In spite of the multiple studies using Transcranial Doppler Sonography (TCDS), few have shown the cerebral blood flow (CBF) pattern among patients with encephalopathy resulting from FHF.

OBJECTIVE

Our objective was to characterize the CBF pattern in these patients through the use of TCDS to provide therapeutic strategies.

METHOD

The TCDS pattern was assessed in five patients diagnosed with FHF and compared with a control group who displayed critical neurologic conditions not associated with FHF. Pulsatile index, systolic, diastolic, and mean velocity of the middle cerebral artery were measured.

RESULTS

The mean age of patients with FHF was 45.4 years. One hundred percent were women, with viral hepatitis as the predominant etiology. A cerebral hypoperfusion pattern was found in 80% of the FHF group and 40% of the control group. In the former group there was no evidence of hyperemia, as there was among 20% of the control group. The mean values of velocity and pulsatile index were 36.6 cm/sec and 2.4, respectively, in the FHF group and 47.8 cm/s and 1.8 in the control group (P=0.268, P=0.402).

CONCLUSIONS

FHF patients show a predominance of cerebral hypoperfusion pattern with mean velocities lower than normal values and an increased pulsatile index. We recommend that clinicians take appropriate measures to improve cerebral perfusion and avoid hypoxia. Hyperventilation as a first level measure is contraindicated.