BACKGROUND: Grass pollen grains are important causes of respiratory allergies. The Philippines has a different grass flora compared to that of western countries, so pollen extracts have to be processed for use in the diagnosis and treatment of respiratory allergies. The local pollen extracts available in clinical practice have not yet been characterized, which is important in improving extract quality.
OBJECTIVE: This study aims to perform physicochemical characterization through protein content determination and gradient sodium-dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of extracts from four grasses: Cynodon dactylon (bermuda grass), Axonopus compressus (carabao grass), Imperata cylindrica (cogon), and Saccharum spontaneum (talahib) and immunologic characterization by identifying its IgE-binding component through immunoblot.
METHODS: This is a descriptive study. The pollen grains were processed into allergen extracts and protein contents were determined. The extracts were separated by gradient SDS-PAGE and subjected to immunoblotting. Bands were visualized using Fluorchem C2 aided with Alpha View Software.
RESULTS: Total protein in the pollen extracts ranged from 281.3-968.61 µg/ml. Protein bands of bermuda were in the 14.4-66.3 kDa range, carabao grass at 3.5-66.3 kDa, cogon at 3.5-200 kDA, and talahib at 21.5-66.3 kDa. A single IgE-binding protein band was seen on immunoblot at 55.4 kDa using a single serum sample.
CONCLUSION: Protein contents of the allergen extracts vary. The molecular weights of the different protein bands seem to correspond to known groups of grass pollen allergens. There was only one IgE-binding protein band seen on preliminary immunoblot.

Allergens ; Bermuda ; Cynodon ; Electrophoresis, Polyacrylamide Gel ; Galectin 3 ; Immunoblotting ; Immunoglobulin E ; Molecular Weight ; Philippines ; Poaceae ; Pollen ; Respiratory Hypersensitivity ; Saccharum ; Sodium ; Sodium Dodecyl Sulfate

OBJECTIVES:The present study aims to determine the frequency of occurrence of NAT2*4, NAT2*5A, NAT2*6B, NAT2*7A and NAT2*14A alleles by PCR-RFLP among Filipino volunteers. These alleles correspond to substitutions in the following sites: C341T, G590A, G857A and G191A, respectively, of the NAT2 gene. The presence of specific SNP combination was also used to deduce acetylation status and estimate genotype frequency and describe them in comparison with other populations based on literature.
METHODS: Genomic DNA from peripheral blood lymphocytes from 129 healthy Filipino volunteers was used to amplify the NAT2 gene segment. The RFLP analysis was done by restricting the expected PCR product with Kpn1, Taq1, BamH1 and Msp1/Al1, respectively, to detect the 4 alleles: NAT2*4, NAT2*5A, NAT2*6B, NAT2*7A and NAT2*14A.
RESULTS:The calculated allelic frequencies in Hardy-Weinberg equilibrium of NAT2*5A (C481T), NAT2*6B (G590A), NAT2*7A (G857A) and NAT2*14A (G191A) were 0.058, 0.097, 0.182 and 0.046, respectively. NAT2*4 had an allele frequency of 0.617. Nine genotypes were determined: NAT2*4/*4, NAT2*4/*5A, NAT2*4/*6B, NAT2*4/*7A, NAT2*4/*14A, NAT2*5A/*7A, NAT2*6B/*7A, NAT2*6B/*14A and NAT2*7A/*14A. From these genotypes, acetylator phenotypes were deduced. A trimodal pattern of distribution was established: rapid, intermediate and slow acetylators with the following percentages, 47.3%, 41.1 % and 11.6%. Among the slow acetylator SNPs determined, NAT2*7A was found as the most frequent allele and NAT2*14A was found as the least frequent allele.
CONCLUSION:The study showed the mutation profile and observed genotypic similarities and differences of Filipinos with other Asian populations and Americans and other Caucasians based on literature. The results also suggest a trimodal pattern of distribution of acetylators and lesser number of slow acetylators among Filipino populations, a characteristic similar to other Asian populations but significantly different from Americans and other Caucasians. The occurrence of NAT2*7A and NAT2*14A can be further sequenced to verify the observed genotype.

Human ; Male ; Female ; Aged ; Middle Aged ; Adult ; Young Adult ; Adolescent ; Acetylation ; Alleles ; Asian Continental Ancestry Group ; Base Sequence ; Dna ; Gene Frequency ; Genomics ; Genotype ; Lymphocytes ; Merozoite Surface Protein 1 ; Mutation ; Phenotype ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Polymorphism, Single Nucleotide ; United States ; Volunteers ; Genes ; Polymorphism, Genetic

Although statins reduced cardiovascular mortality, these drugs did not prevent myocardial infarction in some patients. Previous studies showed that genetic variation in cholesteryl ester transfer protein (CETP) gene was linked to this response. The identified gene is characterized by two different variants: B1 and B2 alleles identified by the presence and absence, respectively, of a restriction site for the enzyme Taq1 in intron 1. The present study identified the variation in Taq1B of the gene using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) in 130 patients. An association study of Taq1B with the response of 24 middle-aged dyslipidemic patients to simvastatin treatment for 8 weeks was also done. The overall allele frequencies of B1 and B2 alleles were 0.548 and 0.462, respectively. The genotype frequencies were in Hardy-Weinberg equilibrium. The distinguishing feature of individuals with B1B1 genotype when treated with simvastatin was their rapid increase in high density lipoprotein (HDL) observed after 2 weeks which continued till the 8th week treatment. The expected HDL elevation among individuals with B1B2 genotype was observed only after the 8th week simvastatin treatment.

Human ; Middle Aged ; Alleles ; Cholesterol Ester Transfer Proteins ; Gene Frequency ; Genotype ; Hydroxymethylglutaryl-coa Reductase Inhibitors ; Introns ; Lipoproteins, Hdl ; Myocardial Infarction ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Simvastatin

Introduction. The Research and Biotechnology Division of St. Luke's Medical Center (SLMC-RBD) acquired a transmission electron microscope (TEM) in 1996. As a joint facility with the Institute of Pathology, the Electron Microscope Facility (EMF) is used for both research and clinical purposes. This paper aims to establish the clinical and research usage, as well as identify the most common referring institutions. Methodology. Data records of the EMF at the SLMC-RBD from January 1997 to December 2004 were reviewed. All submitted samples for TEM were initially categorized according to type of request (clinical or research). Thereafter, the samples under each category were classified according to (1) tissue type or site of biopsy and (2) its referring hospital or institution. Yearly data of these classifications were plotted and reviewed, and from this data, we evaluated the trend of clinical and research TEM usage. Results. This study has shown that the trend of clinical electron microscopy in the local setting is comparable to that of other institutions where renal, muscular, nerve, and skin samples dominate the scene in this particular order. This finding is also the same with other Asian electron microscopy institutions. The rise and steady decline in the requests for both clinical and research TEM has been attributed to the use of newer diagnostic techniques such as immunohistochemistry and molecular pathology. The economic situation and long turnaround time in processing may also be a factor in TEM usage. Conclusion and Recommendations. With the steady decline of electron microscopy use worldwide, strategies have been introduced to enhance its usage. Examples of these strategies include continuous information dissemination to clinicians, research scientists and the layman about the usefulness of TEM and its ever-growing applications for use, monthly newsletters containing "a case for the month" feature, which may be circulated within the physicians practicing within the center and the medical staff organizations in the locality. Such information dissemination has proven to be effective in increasing the knowledge that electron microscopy is useful both as a diagnostic tool and an ancillary procedure. Likewise, since research TEM is seemingly geared towards viral identification, negative staining should be introduced as a diagnostic and screening tool per se, capable of producing results in a matter of minutes; hence a high level of expertise in tracking these problems should be maintained.

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