Human Papilloma Virus DNA Detection in Clinical Samples Using Fluorogenic Probes Based on Oligonucleotide Gated Nanoporous Anodic Alumina Films

In this work, fluorogenic probes based on oligonucleotide capped nanoporous anodic alumina films are developed for specific and sensitive detection of human papilloma virus (HPV) DNA. The probe consists of anodic alumina nanoporous films loaded with the fluorophore rhodamine B (RhB) and capped with oligonucleotides bearing specific base sequences complementary to genetic material of different high-risk (hr) HPV types. Synthesis protocol is optimized for scale up production of sensors with high reproducibility. The sensors' surfaces are characterized by scanning electron microscopy (HR-FESEM) and atomic force microscopy (AFM) and their atomic composition is determined by energy dispersive X-ray spectroscopy (EDXS). Oligonucleotide molecules onto nanoporous films block the pores and avoid diffusion of RhB to the liquid phase. Pore opening is produced when specific DNA of HPV is present in the medium, resulting in RhB delivery, that is detected by fluorescence measurements. The sensing assay is optimized for reliable fluorescence signal reading. Nine different sensors are synthesized for specific detection of 14 different hr-HPV types in clinical samples with very high sensitivity (100%) and high selectivity (93-100%), allowing rapid screening of virus infections with very high negative predictive values (100%).

Effects of soil organic matter content on cadmium toxicity in Eisenia fetida: implications for the use of biomarkers and standard toxicity tests

Bioavailability is affected by soil physicochemical characteristics such as pH and organic matter (OM) content. In addition, OM constitutes the energy source of Eisenia fetida, a well established model species for soil toxicity assessment. The present work aimed at assessing the effects of changes in OM content on the toxicity of Cd in E. fetida through the measurement of neutral red uptake (NRU) and mortality, growth, and reproduction (Organisation for Economic Co-operation and Development [OECD] Nos. 207 and 222). Complementarily, metallothionein (MT) and catalase transcription levels were measured. To decrease variability inherent to natural soils, artificial soils (Organization for Economic Cooperation and Development 1984) with different OM content (6, 10, and 14%) and spiked with Cd solutions at increasing concentrations were used. Low OM in soil decreased soil ingestion and Cd bioaccumulation but also increased Cd toxicity causing lower NRU of coelomocytes, 100 % mortality, and stronger reproduction impairment, probably due to the lack of energy to maintain protection mechanisms (production of MT).Cd bioaccumulation did not reflect toxicity, and OM played a pivotal role in Cd toxicity. Thus, OM content should be taken into account when using E. fetida in in vivo exposures for soil health assessment.

[Clinical management of patient with benign prostatic hyperplasia in Spain]

OBJECTIVES

To identify clinical management of benign prostatic hyperplasia (BPH) in Spain and its associated health care resources.

MATERIAL AND METHODS

A qualitative cross-sectional study was conducted through telephone interviews to general practitioners (GP) and urologists. Information about diagnosis, pharmacologic treatment and follow-up was collected. Results were clustered according to the key variables considered as drivers of clinical practice patterns: BPH diagnosis, severity classification, treatment initiation and follow up of patients.

RESULTS

153 GP and 154 urologists participated in the study. 7 different clinical patterns were identified in primary care (PC). Resource use during diagnosis is relatively homogeneous, reporting a range of 2.0 to 2.6 visits employed and being the most frequent test performed PSA and urine test. Follow-up is heterogeneous; frequency of follow-up visits oscillates from 3.2 to 7.0 visits/patient/year and type of tests performed is different among patterns and within the same pattern. In Urology, 3 clinical patterns were identified. Resource use is homogeneous in the diagnosis and in the follow-up; urologists employed 2 visits in diagnosis and a range of 2.1 to 3.2 visits/patient/year in the follow-up. The most frequent tests both in diagnosis and follow-up are PSA and digital test.

CONCLUSIONS

BPH management shows variability in PC, identifying 7 different clinical practice patterns with different resource use during the follow-up among patterns and within the same pattern. The implementation of clinical guidelines could be justified to reduce heterogeneity.

Demolition of a hospital building by controlled explosion: the impact on filamentous fungal load in internal and external air

The demolition of a maternity building at our institution provided us with the opportunity to study the load of filamentous fungi in the air. External (nearby streets) and internal (within the hospital buildings) air was sampled with an automatic volumetric machine (MAS-100 Air Samplair) at least daily during the week before the demolition, at 10, 30, 60, 90,120, 180, 240, 420, 540 and 660 min post-demolition, daily during the week after the demolition and weekly during weeks 2, 3 and 4 after demolition. Samples were duplicated to analyse reproducibility. Three hundred and forty samples were obtained: 115 external air, 69 'non-protected' internal air and 156 protected internal air [high efficiency particulate air (HEPA) filtered air under positive pressure]. A significant increase in the colony count of filamentous fungi occurred after the demolition. Median colony counts of external air on demolition day were significantly higher than from internal air (70.2 cfu/m(3) vs 35.8 cfu/m(3)) (P < 0.001). Mechanical demolition on day +4 also produced a significant difference between external and internal air (74.5 cfu/m(3) vs 41.7 cfu/m(3)). The counts returned to baseline levels on day +11. Most areas with a protected air supply yielded no colonies before demolition day and remained negative on demolition day. The reproducibility of the count method was good (intra-assay variance: 2.4 cfu/m(3)). No episodes of invasive filamentous mycosis were detected during the three months following the demolition. Demolition work was associated with a significant increase in the fungal colony counts of hospital external and non-protected internal air. Effective protective measures may be taken to avoid the emergence of clinical infections.

Prevalence estimates for hypertension in Latin America and the Caribbean: are they useful for surveillance?

OBJECTIVE

To apply a recently proposed model and assessment tool created by the authors for critically evaluating the data available on the prevalence of hypertension in LAC and assessing their usefulness for surveillance.

METHODS

A bibliographic search to identify all publications that estimated the prevalence of hypertension was performed. Each of the papers located was assessed using a critical appraisal tool.

RESULTS

Of the 58 studies published between 1966 and 2000, only 28 of them (48%) met the critical threshold to be considered useful for surveillance purposes. The distribution of the 28 studies in terms of their usefulness for surveillance was as follows: minimally useful, 16 studies; useful, 8 studies; and very useful, 4 studies. Several methodological shortcomings were identified, from inadequate sampling procedures and sample size to the poor quality of the primary data for planning purposes.

DISCUSSION

Published studies on the prevalence of hypertension in Latin America and the Caribbean have, as a whole, limited usefulness for surveillance activities.

Variation of density, species composition and dominance of rotifers at a shallow tropical reservoir (Broa reservoir, SP, Brazil) in a short scale time

Rotifers are the predominant group of zooplankton found in the majority of reservoirs, constituting more than 60% of the total zooplankton present. Being opportunistic organisms, they easily adapt to changes in environmental conditions, and it is therefore difficult to establish a constant level of composition and occurrence of a species in specific areas at specific times. In order to establish how changes in composition and predominance of a species occurs within a dynamic system, the daily variation in the total density of rotifers and that of the dominant species were studied at short intervals during a period of 20 days at Lobo (Broa) reservoir. Filinia pejleri and Keratella americana were the predominant species, making up 64.3% of the total rotifers. However, during the first five days of the study, there was a predominance of two genera, Conochilus (C. coenobasis and C. unicornis) and Keratella (K. americana and K. cochlearis), with the genus Conochilus being substituted by the genus Filinia from the seventh day onwards, which, together with the genus Keratella, was predominant until the end of the study period. The increase in density of Filinia pejleri and Keratella americana was found to be associated with increased wind speed. The resulting turbulence could cause changes in the behavior and metabolism of the organisms, increasing the rate of reproduction, which in turn could be attributed to the greater availability of food through the suspension of material from the lake bed.

Analysis of enterovirus sequences recovered from the cerebrospinal fluid of patients with epidemic neuropathy

An outbreak of a previously unknown disease, termed epidemic neuropathy (EN), occurred in Cuba between 1991 and 1993. Although nutritional and oxidative stress in the population were rapidly associated with the disease, several findings were not compatible with such stress being the only cause. In the search for biological factors, samples of the cerebrospinal fluid (CSF) from patients with EN were studied and found to have a slowly progressing cytopathic effect (CPE) on VERO cells. Although the results of several studies indicate the presence of enteroviruses, the CPE and other physico-chemical characteristics are not typical of these viruses. Viral sequences have now been amplified from patients' CSF, using oligonucleotide primers homologous to the enterovirus 5' non-coding region. The sequences of the amplified region showed a high degree of variability (7%-69%) when compared with the coxsackievirus (Cox)A9 Griggs used as the reference strain. Furthermore, sequences differing by > 55% (58%-70%) were isolated from a single individual. These results indicate the generation in stressed individuals of enterovirus quasispecies with altered biological properties, and these could have played a major role in the neurological injury of EN.

Calcium signals in cell lines derived from the cerebral cortex of normal and trisomy 16 mice

We established two immortalized cell lines from cerebral cortex of normal (CNh) and trisomy 16 (CTb) mouse fetuses, an animal model of human trisomy 21. Those cells loaded with the fluorescent Ca2+ dyes, Indo-1 and Fluo-3, exhibited increments of intracellular Ca2+ ([Ca2+]i) in response to external glutamate, NMDA, AMPA and kainate. CTb cells exhibited higher basal Ca2+ concentrations and had higher amplitude and slower time-dependent kinetics in the decay than CNh cells, suggesting an impaired Ca2+ buffering capacity in the trisomy 16-derived cell line. Nicotine also induced increments of [Ca2+]i. The CTb cell line could represent a model for studying cellular alterations related to Down syndrome.

Characterization of a virus isolated from the cerebrospinal fluid of patients with epidemic neuropathy

A previously unknown disease, termed epidemic neuropathy (EN), occurred in Cuba between 1991 and 1993. When samples of cerebrospinal fluid (CSF) from 45 patients with EN and 11 controls were inoculated into cultures of VERO cells, almost all (93%) of the samples from the cases of EN but only one (9%) of the control samples produced a slowly progressing cytopathological effect (CPE). Although the results of other studies indicated the presence of a picornavirus-like virus in CSF samples from EN cases, the CPE and other physico-chemical characteristics observed were not those expected of picorn-viruses. Several aetiological factors may have contributed to EN but at least one virus could have played a major role.

Viral isolation from cases of epidemic neuropathy in Cuba

OBJECTIVE

To investigate the possibility of a viral agent in the central nervous system of patients with epidemic neuropathy.

DESIGN

Virus isolation attempts, in cell cultures and suckling mice, from cerebrospinal fluid (CSF) of neuropathy patients and controls undergoing lumbar puncture for unrelated reasons. Serologic studies in patients, contacts, and controls.

SETTING

An epidemic of optic and peripheral neuropathy affected more than 50,000 people in Cuba in 1991 through 1993. Illness was associated with dietary limitations and increased physical demands accompanying the shortages of food and fuel experienced in Cuba since 1989. Most patients responded to parenteral vitamin therapy, and the epidemic began to subside when oral vitamin supplementation was begun for the entire Cuban population.

RESULTS

Coxsackievirus A9 (five isolates) and a similar, less cytopathic virus (100 isolates) were recovered from 105 (84%) of 125 CSF specimens from neuropathy patients. The strains with light cytopathic effect were antigenically related to Coxsackieviruses A9 and B4 by cross-neutralization and immunoblotting assays. Virus persisted in CSF of some patients for 1 to 12 months. Cerebrospinal fluid from patients and both types of virus from cell culture produced illness, including complete posterior flaccid paralysis, in newborn mice, and virus was reisolated from the mice. Mouse tissues and sural nerve biopsy specimens from patients were stained by immunoperoxidase and colloidal gold techniques using hyperimmune rabbit antisera against the virus with light cytopathic effect.

CONCLUSIONS

Coxsackievirus A9 or an antigenically related agent with a light cytopathic effect was present in CSF of 84% of 125 patients with epidemic neuropathy. The role of these agents, probably in combination with nutritional factors, in the pathophysiology of the disease requires further investigation.

Genetics of the HL-A system in a venezuelan heterogeneous population

HL-A antigen and gene frequencies of 206 unrelated adults living in the cities of Caracas and Maracaibo have shown that this heterogeneous Venezuelan population sample possess 11 specificities of the first (LA) HL-A series and 15 specificities of the second (Four) series. HL-A2, HL-A9, HL-A5 and W5 showed frequencies higher than those observed in caucasoid populations. The most frequent haplotypes were 2, W5; 2, 5; 9, 12; 2, 12 and 2, X2. No outstandingly high value for gametic association between the alleles of the 2 HL-A series was observed, but haplotypes formed by antigens with dissimilar frequencies in Caucasoids, Negroids and American Indian tribes have shown statistically significant D values. Genetic distance calculated using the HL-A system alone showed that this population is closer to the average Caucasoid and Negroid population tested at the 5th International Histocompatibility Workshop than to 2 American Indian tribes living in the same country.