Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

[First post-graduate training course in applied genetics]

Dr. Ma. Luisa Enriquez of the Physics Department spoke during the First Post-Graduate Training Course in Applied Genetics of the Flora M. Pascasio, MD Research Foundation, Inc. (FMPRF, Inc.). Enriquez was also Cytogenetics Consultant at St. Luke\u27s Medical Center. DLSU System President Bro. Andrew Gonzalez, FSC serves as Chair of the Board of Trustees of FMPRF, Inc

Diagnostic significance of Philadelphia chromosome BCR-ABL fusion gene detected by GTG-banding and reverse-transcription polymerase chain reaction (RT-PCR) in Filipino patients with chronic myelogenous leukemia (CML)

Introduction. Chronic myelogenous leukemia (CML) is a good clinicla model for showing the capabilities and limitations of cytogenetic and molecular tools in the detection and progress surveillance of the disease. Its hallmark at the level of the chromosomes is the reciprocal translocation of chromosomes 9 and 22 producing the so-called Philadelphia chromosome (shortened chromosome 22). At the molecular level it is characterized by the presence of a BCR-ABL fusion gene believed to be responsible for the malignant transformation of cells. Objectives. 1)To detect the Ph chromosome using the routine cytogenetic GTG banding; 2) To detect BCR-ABL fusion gene by nested RT-PCR; 3) To compare the detection rate of cytogenetic tool with RT-PCR int he diagnosis of CML and disease progression Methods. Peripheral blood samples or bone marrow aspirates were collected from 29 Filipinos with clinically diagnosed CML. The samples were processed both for cell culture and RNA extraction. Chromosomes harvested from primary cultures were differentially stained and analyzed. Qualitative RT-PCR detection of BCR-ABL gene fusion was doe using 2 primers specific for detecting b2a2 and b2a3 fusion. Results. Cytogenetic analyses revealed the presence of the Philadelphia chromosome in 17 (58.62%) patients. Using the RT-PCR method, amplified BCR-ABLL transcripts were detected in 28 (96.55%) patients. Of these, 15 patients have the b3a2 fusion gene, 7 are the b2a2 fusion type and 6 have both the b3a2 and b2a2 fusion. Conclusion. Data obtained from this study show that RT-PCR technique has comparatively higher detection rate than cytogenetic analysis. Thus, the use of RT-PCR proved more sensitive in detecting CML

Preliminary screening for microsatellite instability and loss of heterozygosity in the deleted in colorectal cancer (dcc) gene among Filipino patients with colorectal adenocarcinoma

Objective. This study aimed to detect the presence of microsatellite instability (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 thirty-nine (39) patients with colorectal adenocarcinoma were used in this study. Genomic DNA was extracted and amplified 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 correlation 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 occurrence of colorectal cancer among Filipino patients can be correlated with LOH of the DCC gene but not with MSI. This may be the first study to examine the correlation or lack thereof of MSI and LOH of the DCC gene with colorectal cancer in a Filipino sample population

Determining the apoptotic-inducing property of isothiocyanates extracted from three cultivars of Raphanus sativus Linn. using the comet assay

The apoptotic inducing property of three cultivars of Raphanus sativus L.: white or daikon, red or cherry belle, and large red, were tested on three cancer cell lines: MCF-7, K562, and HT-29. The wild type PAE cells were also incubated with radish extracts for genotoxicity. Each cell line was cultured and treated with either one kind of juice extract or enzymatically hydrolyzed radish sample for 24 hours before harvesting and processing for single cell gel electrophoresis. For each culture set-up, 50 images of cells were captured and analyzed for DNA damage based on three parameters: tail length (TL), percent DNA in the tail (D), and tail moment (TM). Multiple comparisons using Tukey\u27s HSD procedure showed that juice extracts resulted to substantial genotoxicity in MCF-7 cells among the cancer lines based on the superior TL, D, and TM of the comets having 95% CI of [161.16, 231.44], [33.85, 46.63], and [99.97, 157.91], respectively. The juice extracts exhibited no genotoxicity towards normal PAE cells. Extracts from a β-thioglucosidase assisted hydrolysis of white tubers manifested significant disruption of DNA integrity of MCF-7 cells than that of the red tubers (p \u3c 0.0001). Furthermore, DNA fragmentation for MCF-7 cells treated with juice and semi-purified preparations of the white tuber were found to be similar with 95% CI for mean differences of [-112.81, 24.21] for TL, [-18.03, 5.93] for D and [-56.72, 52.15] for TM. From the results, it can be construed that preparations of R. sativus L. can be a substantial source of biologically active constituents that have the ability to cleave DNA in mutant cell lines while being non-genotoxic to wild type immortalized cells. © 2017 Maria Carmen S. Tan et al

CD4+/CD56+ hematodermic neoplasm: Blastic NK cell lymphoma in a 6-year-old child: Report of a case and review of literature

A 6-year-old girl presented with disseminated polymorphous skin lesions of several months\u27 duration, joint pains, recurrent fever, anemia, and inguinal adenopathy. Subsequent evaluation of skin, lymph node, and bone marrow morphology showed infiltration of atypical lymphocytic cells. Immunohistochemical and flow cytometric analysis showed findings consistent with the rare but highly malignant blastic Natural killer cell lymphoma/leukemia also termed CD4/CD56 hematodermic neoplasm. © 2007 Lippincott Williams & Wilkins, Inc

The genotoxic potential of alugbati leaf extracts on MCF-7 cells

To determine the genotoxicity of alugbati (Basella alba Linn. var. rubra) leaf extracts on breast adenocarcinoma, the Comet assay was employed on MCF-7 cells incubated with the following: lyophilized alugbati juice extracts reconstituted with 2 % DMSO (AJ) and in aqueous media (AJ2), and lyophilized alugbati hydrolysate (exogenous myrosinase (E.C. 3.2.3.1) assisted) re- dissolved with 2 % DMSO in culture media (AH). Untreated MCF-7 cells in 2 % DMSO served as the negative control. MANOVA and Post hoc Tukey\u27s HSD were employed to determine statistically significant differences among the samples. First, mutant cells in AJ and AH formed pronounced comet tails indicating that DNA damage had occurred significantly compared to that of the control. Post hoc comparisons between AJ and AH indicated that both samples exhibited comparable effects to MCF-7 cells. Due to the similarity of AJ to AH, it was presumed that hydrolysis occurred during the mechanical process of juice extraction. Second, AJ2 exhibited analogous results with the control; whereas, AJ was found to be statistically different. Aberrant cells incubated with the control and AJ2 trials exhibited relatively minimal genotoxicity as evidenced by intact nuclei. Overall, multiple comparisons illustrated that the most prominent DNA damage was observed by extracts AJ and AH in all parameters. The results of this study suggested that alugbati leaves subjected to enzyme-assisted hydrolysis or juice extractions prepared in DMSO caused considerable DNA damage in MCF-7 cells. © 2019 Jordan Journal of Biological Sciences