[The physicochemical characterization of the agents isolated during the outbreak of epidemic neuropathy in Cuba. I]

This paper reports on the physical and chemical characteristics of agents isolated from serum samples of patients presenting with epidemic neuropathy. The behaviour of isolated enteroviruses was as described for such viruses. Mild cytopathogenic effects-producing agents behaved in a variable form regarding sensitivity to chloroform; on the other hand they were neither sensitive to phosphonoacetic acid (PAA) nor to guanidine hydrochloride (GHC1) and grew in cells previously treated with bromodeoxyuridine (BDUR). These results suggest the presence of agents resembling enteroviruses and enveloped viruses. Further studies for the characterization of such agents need to be performed.

[Standardization of the plaque method for viruses isolated in patients with epidemic neuropathy]

This paper reports on the necessary conditions for plaque development in mild cutopathogenic effect-producing agents which were isolated from samples of the cerebrospinal fluid of patients presenting with epidemic neuropathy.

Using the national cancer institute anticancer drug screen to assess the effect of MRP expression on drug sensitivity profiles

The MRP gene contributes to one form of multidrug resistance. To identify drugs interacting with MRP, we measured MRP mRNA expression by quantitative PCR in 60 cell lines of the National Cancer Institute Anticancer Drug Screen. Expression was detected in all cell lines (highest in lung carcinomas and central nervous system tumors) with a range of 14-fold. A mean graph of MRP mRNA levels was constructed to determine Pearson correlation coefficients (PCCs) with mean graphs of >40,000 compounds using the COMPARE analysis. Only 20 compounds had PCCs of >/=0.500. The PCCs for VP-16, doxorubicin, and vincristine were 0.008, 0.13, and 0.257, respectively. Initially, 36 compounds with PCCs of >/=0.428 were analyzed using two MRP-overexpressing cell lines; low levels of cross-resistance was demonstrated for 23 compounds (1.3-9.4-fold). Twenty-four compounds also were available for further studies. Using a fluorescence activated cell sorter assay to measure competition of calcein efflux from MRP-overexpressing cells, 10 compounds were found to increase calcein retention by >/=2-fold. Ten compounds also were able to reduce ATP-dependent [3H]LTC4 transport into vesicles from MRP-overexpressing cells. These results contrast with previous studies with MDR-1 in which high correlations were found and confirmed for a large number of compounds. Although other assays may be more revealing, in these unselected cell lines, MRP mRNA expression was a poor predictor of drug sensitivity. This raises the possibility that other factors, including conjugating enzymes, glutathione levels, or other transporters, confound the MRP effect.

[Diagnosis of cytomegalovirus infections in patients with HIV infection. Comparison of the indirect immunofluorescence and viral isolation techniques]

The technique for the detection of fluorescent early antigen was compared to the classical method of viral isolation in cells from the human lung. The study was performed with the use of 85 urine samples from 64 patients presenting with HIV infection. The technique for the detection of fluorescent early antigens showed a sensitivity of 91%, an specificity of 97%, and a coincidence of 94% with respect to viral isolation. The main advantage of the technique for the detection of fluorescent early antigens with respect to viral isolation is that the former provides a quicker diagnosis of cytomegalovirus infection within 48-72 hours, besides being easy to perform.

[Detection of cytomegalovirus in urine using DNA-DNA hybridization]

A discussion is conducted on the results of the application of the technique for hybridizing nucleic acids to the detection of cytomegalovirus (CMV) in urine samples. For this purpose, 2 probes from 2 different regions of the genome of the AD169 strain of CMV were used. The results were compared with those obtained by the technique for the detection of early fluorescent antigens (DEFA) in 2 groups of patients at risk of suffering from CMV infections. After assessing the usefulness of the two probes in detecting CMV in urine samples, it was shown that probe B from the region which codes the synthesis of early viral proteins had a coincidence and specificity levels regarding the reference test (DEFA) significantly superior to that of probe A. The results of hybridization may be ready within 48 and 72 hours. The qualification of the technique fo its application to virological diagnosis is discussed.

[Serologic response to some herpesviruses in a group of HIV infected patients]

The titres of antibodies to the herpes simplex virus, cytomegalovirus, and the antigen of viral envelope of Epstein-Barr virus were determined in serum samples from patients infected by the human immunodeficiency virus (HIV) who belonged to groups II (n = 26) and IV (n = 32) according to the present Classification System of HIV infection, as well as in a group of blood donors (n = 52). The geometrical average titres obtained in the different agents were very high in patients having HIV infection with respect to the geometrical average titres observed in blood donors. Patients from group II had titres to the antigen of viral envelope of the Epstein-Barr virus significantly higher than blood donors. Levels of antibodies to these agents in patients from group IV were higher than levels obtained in blood donors. Differences regarding levels of the antigen of viral envelope of the Epstein-Barr virus were highly significant. These results suggest the possible relevance of the Epstein-Barr virus infection in the natural history of AIDS.

[Direct sequencing of an amplified product from a serum sample]

It is reported the nucleotide and amino acidic sequence of a great variability region in the dengue 2 virus genome, starting from the RNA of the original virus with no passage in the isolation systems. It is compared with the first strain of dengue 2 isolated during the 1981 epidemic with 4 passages in lactating mouse. Results show that the nucleotide sequence of serum and of strain A15 are the same.

[Genetic relatedness of the dengue 3 virus isolated in the outbreak of dengue hemorrhagic fever in Nicaragua, 1994]

It is reported the isolation of 2 dengue strains, 3 in samples from Nicaraguan patients suffering from dengue with hemorrhagic manifestations, which showed the reintroduction of this serotype in the region after being 17 years out of circulation. It is also reported the genetic characterization of the isolated strain, which, according to its classification, belongs to the group of dengue 2 strains isolated in Southeast Asi and which have been associated to hemorrhagic dengue. These results suggest the origin of this strain.

[Inhibition of the multiplication of a Coxsackie A9 strain isolated from a patient with epidemic neuropathy by the interferons alfa and gamma]

We present the results of the in vitro action of alpha and gamma interferons and of Intacglobin and Igegam against the 47/93/IPK (Coxsackie A9) strain isolated from the cerebrospinal fluid of a patient with epidemic neuropathy. The in vitro studies showed that the two interferons inhibited the replication of this agent; they also showed the presence of antibodies to it in the Intacglobin and Igegam. The results attained demonstrated that the use of these compounds could be effective for the treatment of this entity.

Chromosome-6-mediated suppression of metastatic ability increases basal expression of UV-inducible superoxide dismutase and induction of p53

Since response to radiation and markers capable of distinguishing metastatic from non-metastatic cells are important, we now use high-stringency mRNA differential display with immune blotting and protein-activity assays, to identify genes induced after exposure to UV in human metastatic C8161 melanoma and its counterpart neo 6.3, in which metastatic ability is suppressed by introduction of neo-tagged chromosome-6 fragments. We cloned and sequenced a 600-bp cDNA 99% homologous to Cu/Zn superoxide dismutase, which was up-regulated after UV irradiation in both metastatic variants, and showed increased basal expression at the mRNA, protein and activity levels in non-metastatic cells. The latter cells also showed greater basal activity of chromosome-6-associated MnSOD, slower proliferation and greater UV-mediated inducibility of the p53 tumor-suppressor protein than did its metastatic counterpart. Our data suggest that suppression of metastatic ability by introduction of neo-tagged chromosome-6 fragments promotes basal expression of superoxide dismutases and increases inducibility of p53 in response to DNA damage.

Carica papaya pollen allergy

BACKGROUND

Carica papaya (CP) trees are widely cultivated in tropical and subtropical areas; however, CP pollen allergy has not been previously described.

OBJECTIVE

To study patients with CP pollen hypersensitivity.

METHODS

A CP pollen extract was elaborated. Skin prick tests (SPTs) with this extract, as well as with commercial papaya fruit and papain extracts, were performed. Specific IgE levels to CP pollen, papaya fruit, and papain were determined. Specific conjunctival challenge tests to the CP pollen extract were also performed. RAST inhibition studies among CP pollen, papaya fruit, and papain were carried out. Twenty atopic patients were used as a control group for in vivo and in vitro tests.

RESULTS

Six patients with clinical histories of seasonal rhinoconjunctivitis or bronchial asthma in relation to CP trees exposure, suggestive of IgE-mediated respiratory allergy, were studied. Commercial SPT and specific serum IgE to papaya fruit and papain were positive in our patients. An IgE-mediated hypersensitivity to a CP pollen extract was demonstrated in all patients, by means of SPTs, specific serum IgE determinations, and conjunctival challenge tests. Control atopic subjects showed negative SPTs, specific IgE, and conjunctival challenge tests to the CP pollen extract. On RAST inhibition studies using CP pollen extract in solid phase, a significant crossreactivity was found among CP pollen, papaya fruit, and papain.

CONCLUSIONS

Our study suggests that papaya flower pollen is able to induce respiratory IgE-mediated allergy. The existence of common allergens among papaya flower pollen, papaya fruit, and papain has been demonstrated by RAST inhibition.

Description of a new kind of MHC DNA sequence in Saguinus oedipus (cotton-top tamarin)

The MHC class I genes of the New World primate the cotton-top tamarin (Saguinus oedipus) are an exception to the high polymorphism and variability usually displayed by this multigene family. In the present work, the cloning and sequencing of a new pseudogene, tentatively named Saoe-Mhc-N4, in this primate species are reported. This new sequence has two characteristic deletions at exon 2, making it very unlikely that any putative protein from this sequence was an antigen-presenting molecule. Comparison of intron 1, intron 2, partial exon 1, exon 2 and partial exon 3 showed little similarity with those of classical class I genes and pseudogenes in S. oedipus and in other primates. Phylogenetic analysis grouped this Saoe-Mhc-N4 sequence with other pseudogenes in S. oedipus. Thus, it seems that Saoe-Mhc-N4 is an inactivated gene or a pseudogene which has been originated by the common process of duplication and subsequent inactivation of MHC class I loci in this primate species.

[Virological diagnosis of an outbreak of fever and rashes caused by parvovirus B19, Cuba, 1995]

The results obtained in the study of an a outbreak of fever and rash occurred in Havana City in March, 1995, are reported. Dengue, measles, rubella, herpes simplex, and Epstein Barr were discarded as causal agents of the outbreak in the samples of 35 patients. Parvovirus B19 was identified as the causing agent of the outbreak by the detection of IgM antibodies and the polymerase chain reaction technique (PCR). The infection produced by this agent was confirmed in 14/18 samples (77.7%) by some of the techniques used. This study makes reference to the first outbreak of Parvovirus B19 that was proved in Cuba.

[Western blot study of sera from patients with epidemic neuropathy]

The immune response of a group of patients with epidemical neuropathy and of controls was studied by the immunoblotting technique against proteins of the Coxsackie virus and the proteins of slow effect isolated in our laboratory. 13 sera of patients with epidemical neuropathy and 9 sera of controls were studied. Of the 13 sera studied, 8 (61.5%) recognized protein VPI and 2 sera (15.3%) protein VP0 of the strain 47.93. Of the 9 controls studied, 4 (44.4%) recognized protein VPI and 3 (33.3%) protein VP0 only. With the antigen prepared from the slow effect strain it was obtained a specific signal in 5 (38.5%) sera of patients and in 2 sera (22.5%) of controls. It should be stressed that in this last case the protein observed had a molecular weight of 41,300 D, and that its size was smaller than that of the preceding protein detected against the strain 47.93 was of 45,000 D.

Lack of HLA-G soluble isoforms in Graves-Basedow thyrocytes and complete cDNA sequence of the HLA-G*01012 allele

The presence of HLA-G mRNA has been studied in thyroid follicular cells from autoimmune patients with Graves' disease. Investigating the possible role of the expression of the HLA-G gene in tissue inflammation, we have found four of the six HLA-G mRNA isoforms described: G1, G2, G3 and G4, but not the soluble ones G5 and G6. Soluble G isoforms may be responsible for inducing tolerance and inflammation control and their absence in autoimmune thyroid follicular cells may induce failure of such control. In addition, the complete coding sequence of HLA-G*01012 has been obtained from thyrocytes and it shows only four synonymous changes with respect to the HLA-G*01011 allele; this further supports the existence of an evolutionary pressure for invariance on HLA-G genes.

Comparison of skin-prick test and specific serum IgE determination for the diagnosis of latex allergy

BACKGROUND

Latex IgE-mediated hypersensitivity has been recognized as an international health problem. However, there is poor information on the efficiency of the diagnostic methods available.

OBJECTIVE

The purpose of this study was to specify the efficiency of several diagnostic methods for latex allergy.

METHODS

We designed a prospective study involving 50 adult patients with latex allergy, as diagnosed by a suggestive clinical history and a positive skin-prick test (SPT) to a latex extract. One control group of 50 subjects paired for age, sex, total IgE levels and latex exposure, and another control group of 30 subjects with pollen allergy were used. A low-ammoniated natural-latex and several glove-latex extracts were elaborated. SPTs with these extracts, as well as with four different commercial-latex extracts were performed. Latex-specific serum IgE was determined by the CAP and the AlaSTAT methods.

RESULTS

Diagnostic sensitivity was 98% for the natural-latex extract SPT, from 90% to 98% for the commercial-latex extract SPT, and from 64% to 96% for the glove-latex extract SPT. Diagnostic specificity of SPT was 100%, and no severe adverse reactions were observed during skin testing. With respect to the latex-specific serum IgE determinations, sensitivity was 86% for the CAP system and 84% for the AlaSTAT assay, and specificity was dependent on the population considered.

CONCLUSION

SPT with natural latex extracts has shown a diagnostic efficiency close to 100%, significantly higher than that of latex-specific serum IgE determination.

[Mechanism of Enterovirus participation in epidemic neuropathy. Physiopathological hypothesis]

During the epidemic neuropathy occurred in Cuba from 1992 to 1993, viral isolations antigenically connected with Coxsackie viruses were obtained from the cerebrospinal fluid of patients. Virological, epidemiological, toxicologic, nutritional, immunological and histopathological investigations were made. Though the disease was related to toxic and nutritional factors, it has been impossible to identify the cause of the epidemic. Taking into consideration the results of the different investigations, we have formulated a comprehensive and multifactorial hypothesis to explain the physiopathological mechanism of the participation of the isolated viruses as mediators in a process of autoimmunity of the pathogeny of the disease.

[Polymerase chain reaction for rapid detection and serotyping of dengue virus in clinical samples]

This study describes the benefits of using reverse transcriptase polymerase chain reaction (RT-PCR) for the rapid detection and typing of dengue virus in clinical samples. Twenty-seven serum specimens from patients with dengue fever and dengue hemorrhagic fever in Colombia, Nicaragua, and Panama were directly subjected to RT-PCR for the detection of dengue virus. The resulting double-stranded DNA product was typed by a second round of PCR amplification (nested PCR) with type-specific primers, viral culture/indirect immunofluorescence (IIF), and enzyme-linked electroimmunoassay for IgM anti-dengue antibodies. The amplified virus genome was detected and typed within 8 hours. Nested RT-PCR, using viral culture and IIF as the gold standard, showed 100% sensitivity; 78% specificity; 69% positive predictive value, and 100% negative predictive value. It is noteworthy that two of the specimens whose results were positive with nested RT-PCR and negative with viral culture showed specific IgM antibodies. The results of the RT-PCR were in close agreement with those obtained through viral culture. This suggests PCR can greatly facilitate the rapid and early diagnosis of dengue infection.

[Consumption of medications in people over age of 65 years: potential problems and associated factors]

OBJECTIVE

To determine the percentage of patients over 65 years of age with potential problems derived from the consumption of medications, and identify associated variables.

DESIGN

A descriptive cross-sectional study.

SETTING

Otero y Paulino Prieto Health Centers (Oviedo).

PATIENTS

A randomly selected group of 298 patients over 65 years.

MEASUREMENTS AND RESULTS

A questionnaire using both interview and clinical case notes provided data about sociodemographic details, perceived state of health, and functional status of patients, and qualitative and quantitative aspects of pharmacological treatment. 222 valid questionnaires were obtained. Once having identified patients with potential treatment problems, the associated variables were studied using bivariant and multivariant analysis. The mean consumption of medications was 3.1. 32.9% of patients had treatment problems (95% CI, 26.7-39.1), identified as drug interactions (54.8%), inappropriate use (36.9%) or both (8.3%). The bivariant analysis showed an association between the presence of problems and number of medications consumed (p < 0.001), prescribers (p < 0.001), diagnostic (p < 0.001), number of visit/year (p < 0.004), patient's own perception of health (p = 0.006), age (p = 0.018), socioeconomic status (p = 0.024) and cultural level (p = 0.039); the associations was not significative for functional status (p = 0.150), sex (p = 0.246), and number of UTB (Use Therapeutic Low) drug used (p = 0.751). Logistic regression showed an association between the presence of problems and patient's perceived state of health (OR, 1.56; 95% CI, 1.03-2.36) and the number of medications consumed (OR, 1.67; 95% CI, 1.41-2).

CONCLUSIONS

A third of the population studied showed potential problems derived from the consumption of medications, through drug interactions and/or inappropriate use. Variables associated with this problems are the patient's perceived ill-health, and the highest consumption of medications.

PTH-responsive osteoblast nuclear matrix architectural transcription factor binds to the rat type I collagen promoter

In connective tissue, cell structure contributes to type I collagen expression. Differences in osteoblast microarchitecture may account for the two distinct cis elements regulating basal expression, in vivo and in vitro, of the rat type I collagen alpha1(I) polypeptide chain (COL1A1). The COL1A1 promoter conformation may be the penultimate culmination of osteoblast structure. Architectural transcription factors bind to the minor groove of AT-rich DNA and bend it, altering interactions between other trans-acting proteins. Similarly, nuclear matrix (NM) proteins bind to the minor groove of AT-rich matrix-attachment regions, regulating transcription by altering DNA structure. We propose that osteoblast NM architectural transcription factors link cell structure to promoter geometry and COL1A1 transcription. Our objective was to identify potential osteoblast NM architectural transcription factors near the in vitro and in vivo regulatory regions of the rat COL1A1 promoter. Nuclear protein-promoter interactions were analyzed by gel shift analysis and related techniques. NM extracts were derived from rat osteosarcoma cells and from rat bone. The NM protein, NMP4, and a soluble nuclear protein, NP, both bound to two homologous poly(dT) elements within the COL1A1 in vitro regulatory region and proximal to the in vivo regulatory element. These proteins bound within the minor groove and bent the DNA. Parathyroid hormone increased NP/NMP4 binding to both poly(dT) elements and decreased COL1A1 mRNA in the osteosarcoma cells. NP/NMP4-COL1A1 promoter interactions may represent a molecular pathway by which osteoblast structure is coupled to COL1A1 expression.