Surface enhanced Raman scattering for robust, sensitive detection and confirmatory identification of dried bloodstains.

An optimized procedure is described for the acquisition of 785 nm excited SERS spectra of dried bloodstains and shown to offer great potential for rapid, portable, highly sensitive and specific, confirmatory identification for forensic applications. Following extraction in 1 µL of 50% acetic acid, a robust, highly reproducible SERS spectrum is observed from dried bloodstains resulting from a hematin-like heme moiety (ferric, high spin). As anticipated, this blood signature can be classified with 100% specificity and sensitivity with respect to the SERS spectra of other body fluids. High quality SERS spectra can be observed from stains of blood diluted by as much as 105. Dried blood spectra acquired on Au and Ag SERS active substrates exhibit very different relative intensities at this electronically, non-resonant excitation wavelength (785 nm) indicating that a strong chemical effect contributes to the SERS enhancement of this body fluid. DFT calculations further confirm the vibrational band assignments of the features seen in these SERS spectra of dried blood.

The broad-spectrum antiviral ribonucleoside ribavirin is an RNA virus mutagen.

The ribonucleoside analog ribavirin (1-beta-D-ribofuranosyl-1,2, 4-triazole-3-carboxamide) shows antiviral activity against a variety of RNA viruses and is used in combination with interferon-alpha to treat hepatitis C virus infection. Here we show in vitro use of ribavirin triphosphate by a model viral RNA polymerase, poliovirus 3Dpol. Ribavirin incorporation is mutagenic, as it templates incorporation of cytidine and uridine with equal efficiency. Ribavirin reduces infectious poliovirus production to as little as 0. 00001% in cell culture. The antiviral activity of ribavirin correlates directly with its mutagenic activity. These data indicate that ribavirin forces the virus into 'error catastrophe'. Thus, mutagenic ribonucleosides may represent an important class of anti-RNA virus agents.

Engineering poliovirus as a vaccine vector for the expression of diverse antigens.

As a step toward developing poliovirus as a vaccine vector, poliovirus recombinants were constructed by fusing exogenous peptides (up to 400 amino acids) and an artificial cleavage site for viral protease 3Cpro to the amino terminus of the viral polyprotein. Viral replication proceeded normally. An extended polyprotein was produced in infected cells and proteolytically processed into the complete array of viral proteins plus the foreign peptide, which was excluded from mature virions. The recombinants retained exogenous sequences through successive rounds of replication in culture and in vivo. Infection of animals with recombinants elicited a humoral immune response to the foreign peptides.

Intracellular determinants of picornavirus replication.

Viruses replicate in a restricted number of hosts and tissues. In addition to viral receptors, several intracellular factors can be involved in determining tissue tropism. Many proteins have recently been implicated in picornavirus translation and RNA replication. Although the functional role of these proteins has not been established in vivo, it is possible that they determine cell-type tropism and the pathogenic outcome of the infection.

Detection of bovine herpesvirus-1 nucleic acid sequences, using a dot-blot hybridization procedure.

A sensitive and specific procedure for the detection of Argentine isolates of bovine herpesvirus-1 was developed. The procedure was based on a dot-blot, nucleic acid hybridization, using 32P, nick-translated, plasmidic probes. The probes contained cloned Bam H1 restriction fragments in the left half of the viral genome. The detection limit of the procedure was 10 pg of viral DNA.

Functional disability and mental impairment as predictors of mortality in community-dwelling elderly Puerto Ricans.

This is a prospective study that explores the role of functional impairment as predictor of one-year mortality in the elderly of rural Puerto Rico. Between September, 1987 and June 1988, 1901 elderly were interviewed at their place of residence. Besides obtaining social and demographic information, assessment of functional status using a modified Katz scale and determination of mental status using the Short Portable Mental Status questionnaire were performed. During the one-year follow-up period 43 participants died. Multiple logistic regression analysis showed that the presence of functional (OR = 5.31) and mental impairment (OR = 2.22) were independent predictors of mortality when adjusted for age, education, gender and income. These findings are consistent with those of other studies, where the presence of functional and mental impairment, detected on admission to a hospital or while living in the community, were associated to a higher mortality.

Prevalence of cognitive and functional impairment in an elderly Puerto Rican population.

Data from the Gurabo census of the elderly, 1987-1988 (n = 1890) were analyzed to determine the prevalence rates for cognitive and functional impairment in that population. Besides socio-demographic questions, the census questionnaire included the Short Portable Mental Status Questionnaire to determine cognitive dysfunction, and the modified Katz Scale to detect functional impairment. The overall prevalence rates were 18.5% and 18.4% for cognitive and functional dysfunction respectively. After multiple logistic regression analysis, cognitive impairment was found to be associated with poor education (OR = 4.0, CI = 2.31-6.93), older age (OR = 2.67, C.I. = 2.00-3.58), functional decline (OR = 2.44, C.I. = 1.83-3.25), female sex (OR = 1.82, C.I. = 1.39-2.40) and low income (OR = 1.49, C.I. = 113-1.98). Functional impairment was found to be associated with cognitive dysfunction (OR = 2.45, C.I. = 1.84-3.27) and older age (OR = 2.08, C.I.-1.59 = 2,72). These findings suggest that a substantial proportion of the elderly in Puerto Rico may require assistance to deal with the consequences of these impairments.

[Description of health status and functional capacity of the 65-year-old and older population residing in the University Region of Health of Puerto Rico]. / Descripción del estado de salud y la capacidad funcional de la población de 65 años o más residente en la Región Universitaria de Salud de Puerto Rico.

This study intended to describe the health and functional status of the population 65 years and over resident in the Puerto Rico University Health Region (municipalities of Canóvanas, Loiza, Carolina and Trujillo Alto, Puerto Rico). Four ninety one hundred elderly subjects selected from a random sample of households, were interviewed. A questionnaire was designed to gather data of the following variables: health conditions, functional capacity, health services utilization, social support and preventive measures. Descriptive measures and chi-square were utilized for the statistical analysis. Findings revealed a population composed mostly of women with a higher prevalence of health conditions than their male counterparts. More than half of the sample report visual problems, arthritis or hypertension. Almost a quarter had diabetes mellitus. The prevalence of these conditions was higher in the age group over 75, with the exception of diabetes. Thirty percent of the sample was classified as functionally dependent, condition that increased with the subject's age. Findings evidence the need of an early assessment in this population in order to intervene with potentially modifiable factors to prevent future disability and improve quality of life of the aged.

[Health status and functional limitations in the elderly population of the University Region of Health of Puerto Rico: methodologic aspects and prevalence estimates]. / Condiciones de salud y limitaciones funcionales en la población de edad avanzada de la Región Universitaria de Salud de Puerto Rico: aspectos metodológicos y estimación de prevalencias.

In order to plan the health services for the elderly population, it is necessary to quantify their health status and their functional capacity. In Puerto Rico, few epidemiological studies have been conducted regarding functional capacity and chronic diseases in the elderly population. One of the difficulties to undertake these studies is the high cost and risks to move this population for clinical exams, in addition to the methodology limitation of self-report in the elderly population. This study shows the use of logistic regression to estimate the prevalence of chronic diseases and functional capacity, when the observed data are not consisted with the planed sampling scheme. Four hundred and eighty-seven elderly persons (65 yr. and over) were interviewed in the municipalities of Canóvanas, Carolina, Loíza and Trujillo Alto in Puerto Rico, using a cross-sectional design. More than half of the elderly had visual problems (IC 95%: 54.8%, 63.8%), arthritis (IC 95%: 52.7%, 61.5%) and hypertension (IC 95%: 47.3%, 56.3%). In the case of hypertension, significant differences (p < 0.05) by sex were observed, where women reported a higher prevalence than men. One of the higher prevalences in the functional capacity status was with urine accidents. More than one-third of the population is estimated to have this problem (IC 95%: 34.7%, 43.4%). One-fourth of the population had limitations with going out for shopping (IC 95%: 23.9%, 31.9%) and using public and private transportation (IC 95%: 19.5%, 26.9%). We conclude that the applied methodology was consistent with the estimation presented in the literature and statistics from the Puerto Rico Health Department. However, it is necessary to continue assessing the design and analytical methodology, in order to undertake consistent and periodic evaluations of the elderly population.

Differences in patient mix: a partial explantation for the excessive Medicare mortality observed in some Puerto Rican hospitals.

Data from a census in a Puerto Rican community were used to retrospectively compare patients admitted to government hospitals in terms of demographic variables, mental status and functional status in the community prior to admission. A total of 268 patients admitted to a hospital at least once during the study period were identified. Patients admitted to government hospitals were poorer, less educated, less functional and had a higher level of mental impairment. However, in comparison to private hospitals, stratified analysis showed consistently higher in-hospital mortality rates among patients admitted to government hospitals when other variables were taken into account.

Increased alanine aminotransferase (ALT-SGPT) activity in Puerto Rican blood donors.

Data was obtained from 4189 volunteer blood donation records in two hospital-based blood banks in Puerto Rico to determine whether Hispanics have higher serum alanine aminotransferase (ALT-SGPT) activity than donors from other racial-ethnic groups. The overall mean value of ALT-SGPT in the study population was 36.84 u/l (range 1-910, standard deviation 37.8). When the logarithm of ALT-SGPT (log ALT) was calculated for all subjects, the overall, mean for log ALT was 1.47 (range 1-2.96, standard deviation 0.27). Analysis of each blood bank's donation records at two different time periods showed a consistently high ALT-SGPT activity even when donations positive for hepatitis B surface antigen or other serologic markers were excluded. Though the causal factor of this finding is not clear, non-infectious environmental such as alcohol consumption should be considered as a probable explanation.

[The aging person in Gurabo: a bio-psychosocial profile of the aging person in a community in Puerto Rico]. / El envejeciente de Gurabo: un perfil biosicosocial del envejeciente en una comunidad de Puerto Rico.

The Department of Family Medicine of the University of Puerto Rico Medicine School performed a census of the inhabitants 60 years and older in the community of Gurabo. A total of 1,890 elderly were interviewed 51% were female and 49% male. Sixty percent were married and twenty-five percent were widowed. Eighty two percent still lived within a family setting and only seventeen percent lived alone 86% owned their own home despite ninety percent reporting incomes below $400.00 per month. Ninety five percent have access to medical services but 63% receive services in multiples sites. Eighteen percent were functionally impaired, fourteen percent intellectually impaired and five percent had impairment in both areas. Preliminary data show that the latter group had an annual mortality rate of 15% compared to only 3.6% and 1.3% respectively in the other two group. We concluded that: 1) functional and mental impairment are indicators of increased mortality. 2) although access to health care is not a problem this health care is episodic and interrupted being provided in multiple different sites.

Reacción adversa a medicamentos (RAM) fija generalizada, debido a gemfibrozilo (GMZ): A propósito de un caso / Case report: generalized fixed drug eruption due to gemfibrozil

El abuso de la ingestión de drogas y la creación de nuevos medicamentos, ha producido un aumento en la aparición de reacción adversa a medicamentos (RAM), los que deben ser siempre informados dada la importancia de su registro. Un tipo de RAM es la erupción fija medicamentosa (EFM). Se revisará un caso de EFM asociada al gemfibrozilo (GMZ) en un paciente chileno de 75 años, quien presentó en dos ocasiones lesiones dermatológicas en la misma localización anatómica, tras la ingestión de GMZ. EFM representa el 5-10% de las RAM y pueden manifestarse en piel y/o mucosas y suelen recurrir en el mismo sitio, cada vez que el paciente consume la droga. Los medicamentos más comunes que producen esta reación son: los antibióticos, analgésicos-anti-inflamatorios no esteroides e hipnóticos. No hemos encontrado publicados casos de EFM a causa de GM. Una EFM ampollar generalizada, es importante diferenciarla clínica e histológicamente del síndrome de Stevens-Johnson o de la necrólisis epidérmica tóxica. Los síntomas, signos, evolución y la histología del caso, nos hace pensar en una EFM bulosa generalizada debido a GMZ.

Poliovirus RNA replication requires genome circularization through a protein-protein bridge.

The mechanisms and factors involved in the replication of positive stranded RNA viruses are still unclear. Using poliovirus as a model, we show that a long-range interaction between ribonucleoprotein (RNP) complexes formed at the ends of the viral genome is necessary for RNA replication. Initiation of negative strand RNA synthesis requires a 3' poly(A) tail. Strikingly, it also requires a cloverleaf-like RNA structure located at the other end of the genome. An RNP complex formed around the 5' cloverleaf RNA structure interacts with the poly(A) binding protein bound to the 3' poly(A) tail, thus linking the ends of the viral RNA and effectively circularizing it. Formation of this circular RNP complex is required for initiation of negative strand RNA synthesis. RNA circularization may be a general replication mechanism for positive stranded RNA viruses.

Poliovirus requires a precise 5' end for efficient positive-strand RNA synthesis.

Poliovirus infectious RNA can be synthesized in vitro using phage DNA-dependent RNA-polymerases. These synthetic transcripts contain several extra nucleotides at the 5' end, which are deleted during replication to generate authentic viral genomes. We removed those 5'-end extra nucleotides utilizing a hammerhead ribozyme to produce transcripts with accurate 5' ends. These transcripts replicate substantially more rapidly in cell culture, demonstrating no lag before replication; they also replicate more efficiently in Xenopus laevis oocytes and in in vitro translation-replication cell extracts. In both systems, an exact 5' end is necessary for synthesis of positive-strand RNA but not negative-strand RNA.

An RNA sequence of hundreds of nucleotides at the 5' end of poliovirus RNA is involved in allowing viral protein synthesis.

Twenty-one mutations were engineered in the 5' noncoding region of poliovirus type 1 RNA, using an infectious cDNA copy of the viral genome. RNA was made from these constructs and used to transfect HeLa cells. Viable virus was recovered from 12 of these transfection experiments, including six strains with a recognizable phenotype, mapping in four different regions. One mutant of each site was studied in more detail. Mutant 5NC-11, having a 4-base insertion at nucleotide 70, was dramatically deficient in RNA synthesis, suggesting that the far 5' end of the genome is primarily involved in one or more steps of RNA replication. Mutants 5NC-13, 5NC-114, and 5NC-116, mapping at nucleotides 224, 270, and 392, respectively, showed a similar behavior; they made very little viral protein, they did not inhibit host cell translation, and they synthesized a significant amount of viral RNA, although with some delay compared with wild type. These three mutants were efficiently complemented by all other poliovirus mutants tested, except those with lesions in protein 2A. Our results imply that these three mutants map in a region (region P) primarily involved in viral protein synthesis and that their inability to shut off host cell translation is secondary to a quantitative defect in protein 2A. The exact function of region P is still to be determined, but our data supports the hypothesis of a single functional module allowing viral protein synthesis and extending over several hundred nucleotides.