1.Isolation of Acanthamoeba Genotype T4 from a Non-Contact Lens Wearer from the Philippines
Corazon C. Buerano ; Abigail D. Trinidad ; Lindsay Sydney N. Fajardo ; Irwin Y. Cua ; Michael O. Baclig ; Filipinas F. Natividad
Tropical Medicine and Health 2014;42(4):145-147
We report the case of a 76-year old Filipino male who presented with pain, redness, and blurring of vision of the right eye. Corneal scraping was done and sent to the St. Luke’s Research and Biotechnology Group for detection and identification of the infectious agent. Morphological detection was performed by allowing the organism from the scraping to grow in 1.5% non-nutrient agar plate with heat-killed E. coli. Trophozoites with acanthopodia and double-walled cysts characteristic of Acanthamoeba were observed within the first and second week of observations, respectively. Molecular identification of the amoebae at the genus level based on the presence of Acanthamoeba-specific amplimer S1, ASA.S1 confirmed the morphological identification. Genotyping through sequence revealed that the organism belonged to T4, which is the genotype commonly present in the eye of keratitis patients.
2.Isolation of Acanthamoeba genotype T4 from a non-contact lens wearer from the Philippines
Corazon C. Buerano ; Abigail D. Trinidad ; Lindsay Sydney N. Fajardo ; Irwin Y. Cua ; Michael O. Baclig ; Filipinas F. Natividad
Tropical Medicine and Health 2014;():-
We report a case of a 76-year old Filipino male from the province of Porac, Pampanga who presented with pain, redness, and blurring of vision of the right eye (oculus dexter, OD) on 25 February 2009. One and a half weeks prior to consultation, patient complained of right eye discharge and lid swelling. The patient consulted an ophthalmologist and was given unrecalled topical eye medications. There was no improvement from the symptoms and patient complained of worsening pain and redness in the right eye. The patient was a non-contact lens wearer and he denied any trauma to the right eye. However, he admitted to washing both eyes with tap water. Visual acuity in the right eye was counting fingers at 3 feet. Slit lamp examination showed diffuse conjunctival injection. There was note of a ring-like infiltrate in the cornea almost extending to the limbus. There was also note of significant anterior chamber cells reaction and hypopyon. Primary working impression was Acanthamoeba keratitis (AK), OD. Corneal scraping was done and sent to the St. Luke's Research and Biotechnology for detection and identification of the infectious agent. Morphological detection was done by allowing the organism from the scraping to grow in 1.5% non-nutrient agar plate with heat-killed E. coli. Trophozoites with acanthopodia and double-walled cysts characteristic of Acanthamoeba were observed within the first and second week of observations, respectively. Molecular identification of the amoebae at the genus level based on the presence of Acanthamoeba-specific amplimer S1, ASA. S1 (a partial 18S ribosomal DNA gene) confirmed the morphological identification (band at 461-bp). Genotyping through sequence revealed that the organism belonged to T4, which is the genotype commonly present from the eye of keratitis patients.
3.Preliminary screening for microsatellite instability and loss of heterozygosity in the deleted in colorectal cancer (DCC) gene among Filipino patients with colorectal adenocarcinoma.
Arnante Michael Ernesto S ; Enriquez Ma. Luisa D ; Cao Ernelea P ; Natividad Filipinas F
Acta Medica Philippina 2014;48(4):17-22
OBJECTIVE: This study aimed to detect the presence of microsatellite (MSI) and loss of heterozygosity (LOH) of the Deleted in Colorectal Cancer (DCC) gene in normal and tumor tissues of Filipino colorectal cancer patients and examine its correlation with age, gender, tumor grade, tumor stage and site of lesion.
METHODS: Paired frozen normal and tumor tissues from thirtynine (39) patients with colorectal adenocarcinoma were used by polymerase chain reaction (PCR). Single strand conformation polymorphism - polyacrylamide gel electrophoresis (SSCP - PAGE) was used to determine MSI and restriction fragment length polymorphism (RFLP) was used to study LOH.
RESULTS: Based on our data, out of the 39 patients, 10 showed LOH of the DCC gene using the LOH markers VNTR, M2 and M3, while no MSI was detected in the samples using the MSI markers BAT25 and BAT26. Correlation with clinicopathological characteristics showed that there is significance for the site of lesion. The LOH has correclation with tumor samples from the colon but not with those from the rectum.
CONCLUSION: Preliminary screening for MSI and LOH of the DCC gene shows that occurrences of colorectal cancer among Filipino patients can be correlated with LOH of the DCC gene with colorectal cancer in a Filipino sample population.
Human ; Male ; Female ; Aged 80 And Over ; Aged ; Middle Aged ; Adult ; Genes, Dcc ; Polymorphism, Single-stranded Conformational ; Colorectal Neoplasms ; Adenocarcinoma ; Loss Of Heterozygosity
4.Concordance of hepatitis C virus subtyping by non-structural 5A and non-structural 5B sequencing.
Baclig Michael O. ; Chan Veronica F. ; Ramos John Donnie A. ; Gopez-Cervantes Juliet ; Natividad Filipinas F.
Acta Medica Philippina 2010;44(1):16-19
The non-structural 5B (NS5B) gene is the target region to identify hepatitis C virus (HCV) subtypes. However, it is not always possible to amplify this region because of inherently high sequence variability. Nucleotide sequences of the non-structural 5A (NS5A) and NS5B genes and its concordance were determined from patients infected with HCV genotype 1 (HCV-1). Among the 30 HCV-1 samples, 7 (23%) were identified as subtype 1a and 23 (77%) were identified as 1b by NS5A sequencing. Sequence analysis of the NS5B showed that 13 (43%) were identified as 1a and 17 (57%) were identified as 1b. Out of the 13 samples identified as 1a by NS5B, 6 (46%) were correctly identified by NS5A. Of the 17 samples identified as 1b by NS5B, 16 (94%) were correctly identified by NS5A. The presence of glutamic acid (E) or aspartic acid (D) at position 2225 in the NS5A differentiates 1a from 1b subtypes, respectively. This study showed that the NS5A sequencing can identify HCV-1a and 1b subtypes with predictive values of 86% and 70% of cases, respectively. The overall concordance with NS5B was 73%. NS5B sequence analysis remains to be the reference method to identify HCV-1 subtypes. NS5A sequencing may be used to complement NS5B sequencing in case the NS5B gene cannot be successfully amplified.
Human ; Male ; Female ; Aged ; Middle Aged ; Adult ; ; Aspartic Acid ; Genotype ; Glutamic Acid ; Hepacivirus ; Hepatitis C ; Nucleotides ; Sequence Analysis ; Viral Nonstructural Proteins
5.Applications of transmission electron microscopy at St. Luke's Medical Center: An eight-year experience.
Miguel Martin N. MORENO II ; Michelle Y. SO ; Dennis B. BACANI ; Ronald O. ALQUIZA ; Samuel Alan B. INOVEJAS ; Cynthia A. MAPUA ; Ronald R. MATIAS ; Filipinas F. NATIVIDAD
Journal of the Philippine Medical Association 2006;86(1):43-47
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.
None


Result Analysis
Print
Save
E-mail