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1.
Heliyon ; 10(3): e25064, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38352738

ABSTRACT

Breast cancer remains a significant global health concern, necessitating the development of novel therapeutic approaches. In this study, we investigate the role of Eu3+ doped hydroxyapatite nanocomposites (Han: Eu3+) in the treatment of MCF7 and 4T1 breast cancer cell lines. Furthermore, we explored the structural and luminescent properties of these nanocomposites. Han: Eu3+ were synthesized using a modified co-precipitation method, and their morphology and crystal structure were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD) in which the average crystalline size of Han: Eu3+ was found to be 25 nm, rendering them suitable for cellular uptake and targeted therapy. To gain insights into the luminescent properties of Han: Eu3+, their excitation and emission spectra were recorded using photoluminescence spectrometer. The characteristic red emission of Eu3+ ions was observed upon excitation, validating the successful doping of Eu3+ into the Han lattice, which was confirmed by the CIE chromaticity coordinate study. These luminescent properties of Han: Eu3+ hold promise for potential applications in bioimaging. To evaluate the efficacy of Han: Eu3+ in breast cancer treatment, MCF7 and 4T1 cell lines were exposed to varying concentrations of the nanocomposites. Cell viability assays revealed a concentration-dependent reduction in cell viability, indicating the potential anticancer activity of Han: Eu3+. The findings of this study contribute to the expanding field of nanomedicine, bringing targeted breast cancer treatments and us closer to more effective.

2.
Sci Adv ; 9(20): eadg0432, 2023 05 19.
Article in English | MEDLINE | ID: mdl-37196085

ABSTRACT

Interfacial tension plays an important role in governing the dynamics of droplet coalescence and determining how condensates interact with and deform lipid membranes and biological filaments. We demonstrate that an interfacial tension-only model is inadequate for describing stress granules in live cells. Harnessing a high-throughput flicker spectroscopy pipeline to analyze the shape fluctuations of tens of thousands of stress granules, we find that the measured fluctuation spectra require an additional contribution, which we attribute to elastic bending deformation. We also show that stress granules have an irregular, nonspherical base shape. These results suggest that stress granules are viscoelastic droplets with a structured interface, rather than simple Newtonian liquids. Furthermore, we observe that the measured interfacial tensions and bending rigidities span a range of several orders of magnitude. Hence, different types of stress granules (and more generally, other biomolecular condensates) can only be differentiated via large-scale surveys.


Subject(s)
Cytoskeleton , Stress Granules
3.
Appl Radiat Isot ; 198: 110854, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37209491

ABSTRACT

To analyse the fetal dose in all three trimesters in patients treated for brain tumors during pregnancy, a modified rando phantom representing three different trimesters was used with provisions for insertion of ion-chamber and Optically Simulated Luminescence Dosimeter (OSLD). The measurement regions were chosen at the level of fundus, umbilicus and pubis. Seven different treatment plans with 6FF and 6FFF beam energies were generated. Treating pregnant patients with brain tumors is safe irrespective of planning modalities except 3DCRT plan where the dose is 10.24 cGy.


Subject(s)
Optically Stimulated Luminescence Dosimetry , Radiotherapy, Conformal , Humans , Luminescence , Radiation Dosimeters , Radiotherapy, Conformal/methods , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted/methods , Phantoms, Imaging , Optically Stimulated Luminescence Dosimetry/methods
4.
Int J Mol Sci ; 24(7)2023 Mar 29.
Article in English | MEDLINE | ID: mdl-37047429

ABSTRACT

DJ-1 is a redox sensitive protein with a wide range of functions related to oxidative stress protection. Mutations in the park7 gene, which codes for DJ-1 are associated with early onset familial Parkinson's disease and increased astrocytic DJ-1 levels are found in pathologic tissues from idiopathic Parkinson's disease. We have previously established a DJ-1 knockout zebrafish line that developed normally, but with aging the DJ-1 null fish had a lowered level of tyrosine hydroxylase, respiratory mitochondrial failure and a lower body mass. Here we have examined the DJ-1 knockout from the early adult stage and show that loss of DJ-1 results in a progressive, age-dependent increase in both motoric and non-motoric symptoms associated to Parkinson's disease. These changes coincide with changes in mitochondrial and mitochondrial associated proteins. Recent studies have suggested that a decline in NAD+ can contribute to Parkinson's disease and that supplementation of NAD+ precursors may delay disease progression. We found that the brain NAD+/NADH ratio decreased in aging zebrafish but did not correlate with DJ-1 induced altered behavior. Differences were first observed at the late adult stage in which NAD+ and NADPH levels were decreased in DJ-1 knockouts. Considering the experimental power of zebrafish and the development of Parkinson's disease-related symptoms in the DJ-1 null fish, this model can serve as a useful tool both to understand the progression of the disease and the effect of suggested treatments.


Subject(s)
Parkinson Disease , Animals , Parkinson Disease/metabolism , Zebrafish/genetics , Zebrafish/metabolism , NAD/metabolism , Brain/metabolism , Protein Deglycase DJ-1/genetics , Protein Deglycase DJ-1/metabolism
5.
J Neuropathol Exp Neurol ; 82(2): 160-168, 2023 01 20.
Article in English | MEDLINE | ID: mdl-36592076

ABSTRACT

Immune effector cell-associated neurotoxicity syndrome (ICANS) is a prevalent condition seen after treatment with chimeric antigen receptor T-cell (CAR T) therapy and other cancer cell therapies. The underlying pathophysiology and neuropathology of the clinical syndrome are incompletely understood due to the limited availability of brain tissue evaluation from patient cases, and a lack of high-fidelity preclinical animal models for translational research. Here, we present the cellular and tissue neuropathologic analysis of a patient who experienced grade 4 ICANS after treatment with anti-CD19 CAR T therapy for mantle cell lymphoma. Our pathologic evaluation reveals a pattern of multifocal demyelinating leukoencephalopathy associated with a clinical course of severe ICANS. A focused analysis of glial subtypes further suggests region-specific oligodendrocyte lineage cell loss as a potential cellular and pathophysiologic correlate in severe ICANS. We propose a framework for the continuum of neuropathologic changes thus far reported across ICANS cases. Future elucidation of the mechanistic processes underlying ICANS will be critical in minimizing neurotoxicity following CAR T-cell and related immunotherapy treatments across oncologic and autoimmune diseases.


Subject(s)
Leukoencephalopathy, Progressive Multifocal , Lymphoma, Mantle-Cell , Neurotoxicity Syndromes , Receptors, Chimeric Antigen , Animals , Immunotherapy, Adoptive , Neurotoxicity Syndromes/etiology , Neurotoxicity Syndromes/therapy , Adaptor Proteins, Signal Transducing
6.
Luminescence ; 38(1): 71-82, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36511851

ABSTRACT

Eu3+ -doped-bismuth-based phosphate glasses with chemical equation (60 - x)P2 O5 -20Bi2 O3 -10Na2 CO3 -10SrF2 -xEu2 O3 (PBNSEu), (where x = 0, 0.1, 0.5, 1.0, 1.5 and 2 mol%) were fabricated using the melt-quenching method. Obtain X-ray diffraction (XRD), energy-dispersive X-ray (EDAX), and Fourier transform infrared (FTIR) spectra were used to characterize the structure of the prepared PBNSEu glass. The J-O (Judd-Ofelt) intensity parameters (Ω2 , Ω4 ) were estimated using photoluminescence emission spectra. When excited with a xenon lamp at λexc  = 394 nm, the most intense red-emission transition occurred at ~612 nm (5 D0 →7 F2 ). J-O intensity parameters were used to calculate radiative properties, whereas the radiative branching ratio (ßR ), radiative transition probability (AR ), radiative lifetime (τR ), and total radiative transition rate (Aτ ) were calculated for the transitions 5 D0 →7 FJ (where J = 0-4) and were obtained in the emission spectra for europium ion-doped in the current glass. Using the CIE1931 chromaticity coordinates axes, the colours of various concentrations of Eu3+ ion-doped PBNS glass were evaluated using the emission spectra. Temperature-dependent luminescence spectra were recorded for the optimized PBNSEu20 glass to calculate the activation energy. These results strongly suggested red components in w-LEDs and visible display laser applications.


Subject(s)
Bismuth , Light , Bismuth/chemistry , Glass/chemistry , Phosphates/chemistry , Lasers
7.
Adv Mater ; 34(34): e2202913, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35796384

ABSTRACT

Coacervates droplets have long been considered as potential protocells to mimic living cells. However, these droplets lack a membrane and are prone to coalescence, limiting their ability to survive, interact, and organize into higher-order assemblies. This work shows that tyrosine-rich peptide conjugates can undergo liquid-liquid phase separation in a well-defined pH window and transform into stable membrane-enclosed protocells by enzymatic oxidation and cross-linking at the liquid-liquid interface. The oxidation of the tyrosine-rich peptides into dityrosine creates a semipermeable, flexible membrane around the coacervates with tunable thickness, which displays strong intrinsic fluorescence, and stabilizes the coacervate protocells against coalescence. The membranes have an effective molecular weight cut-off of 2.5 kDa, as determined from the partitioning of small dyes and labeled peptides, RNA, and polymers into the membrane-enclosed coacervate protocells. Flicker spectroscopy reveals a membrane bending rigidity of only 0.1kB T, which is substantially lower than phospholipid bilayers despite a larger membrane thickness. Finally, it is shown that enzymes can be stably encapsulated inside the protocells and be supplied with substrates from outside, which opens the way for these membrane-bound compartments to be used as molecularly crowded artificial cells capable of communication or as a vehicle for drug delivery.


Subject(s)
Artificial Cells , Artificial Cells/chemistry , Peptides , Polymers , RNA , Tyrosine
8.
J Med Phys ; 47(3): 225-234, 2022.
Article in English | MEDLINE | ID: mdl-36684705

ABSTRACT

Aim: The aim of this study was to measure the dose to planning target and organ at risk (OAR) using Alderson Rando phantom for various treatment techniques in left breast radiotherapy and to estimate the secondary cancer incidence. Materials and Methods: Eleven different combinations of plans containing four techniques (three dimensional conformal radiotherapy, intensity-modulated radiation therapy [IMRT], volumetric modulated arc therapy [VMAT], and combination of 3DCRT and VMAT plans (HYBRID)) were created with 6 MV FF and 6 MV FFF (flattening filter and flattening filter-free) photon energies in phantom. Planned target volume and OAR doses in 23 different locations were measured using optically stimulated luminescence dosimeter (OSLD) and EBT3 films. Assuming the age of exposure as 30 years, lifetime attributable risk (LAR) was estimated based on excess absolute risk (EAR) models outlined in the Biological Effects of Ionizing Radiation VII report. Results: Film showed maximum deviations of 6.15% with IMRT_C_FF plan when compared with treatment planning system (TPS). The maximum percentage difference of 1.7% was found with OSLD measurement when compared with TPS for VMAT_T_FFF plan. EAR estimation was done for all the OARs including target. The LARs for left lung, right lung, and right breast were evaluated. The maximum LAR values of 2.92 ± 0.14 were found for left lung with VMAT_C_FFF plans. Conclusion: This study shows that both OSLD and EBT3 films are suitable for dose measurements using Rando phantom. OSLD shows superior results when compared with films, especially with relatively larger distances. Maximum LAR values were found with VMAT_C_FFF plans. Considering the secondary cancer risk associated with the patients treated in the younger age group, it is suggested that in vivo dose estimation should be a part of treatment quality audit whenever possible.

9.
Asian Pac J Cancer Prev ; 22(8): 2577-2585, 2021 Aug 01.
Article in English | MEDLINE | ID: mdl-34452573

ABSTRACT

BACKGROUND: The purpose of this study was to evaluate the surface dose (SD) of 6 and 10 MV flattening filter beam (FF) and flattening filter free (FFF) beam for different square field sizes in three Beam-matched medical linear accelerators using a parallel-plate ionization chamber. MATERIALS AND METHODS: The experiment was carried out in a phantom composed of 40×40 cm2 solid Water slabs of varying thickness. Further sheets of solid water phantom were added to take readings in the build-up region for both SSD and SAD technique. Surface doses are measured with a PPC-05 chamber and DOSE 1 electrometer, at measurement depth of 1 mm interval and all results are plotted relative to the dose measured at Dmax for various field sizes. Surface dose readings are therefore reported as relative surface dose. RESULTS: Surface dose increased linearly with field size for both FF and FFF photon beams in all three beam-matched linear accelerators in both SSD and SAD setup. The surface dose of FFF was higher than FF beams in all field sizes. For the given energy the surface dose difference (relative to 10x10 cm2 field size of 6FF) between FF and FFF beam was larger for large field size. For 6FF and 6FFF beam the surface dose difference for 5x5 cm2 is -5.27%, and for 30x30 cm2 it is 12.91%. The measured surface dose differences between linear accelerators are not statically significant (P>0.989). Similarly, the surface dose difference between SSD and SAD setup was also analysed and had no statistical significance (P>0.849). CONCLUSION: Study showed that the surface dose difference between beam-matched linear accelerators are insignificant. The surface dose difference between SSD and SAD setup were also found negligible. Most importantly, changing patients between beam-matched linear accelerators will not have any significant changes in surface dose in clinical setup.
.


Subject(s)
Filtration/instrumentation , Particle Accelerators/instrumentation , Phantoms, Imaging , Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Intensity-Modulated/methods , Humans , Radiotherapy Dosage
10.
NAR Genom Bioinform ; 3(2): lqab038, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34056595

ABSTRACT

The rate of translation can vary depending on the mRNA template. During the elongation phase the ribosome can transiently pause or permanently stall. A pause can provide the nascent protein with the time to fold or be transported, while stalling can serve as quality control and trigger degradation of aberrant mRNA and peptide. Ribosome profiling has allowed for the genome-wide detection of such pauses and stalls, but due to library-specific biases, these predictions are often unreliable. Here, we take advantage of the deep conservation of protein synthesis machinery, hypothesizing that similar conservation could exist for functionally important locations of ribosome slowdown, here collectively called stall sites. We analyze multiple ribosome profiling datasets from phylogenetically diverse eukaryotes: yeast, fruit fly, zebrafish, mouse and human to identify conserved stall sites. We find thousands of stall sites across multiple species, with the enrichment of proline, glycine and negatively charged amino acids around conserved stalling. Many of the sites are found in RNA processing genes, suggesting that stalling might have a conserved role in RNA metabolism. In summary, our results provide a rich resource for the study of conserved stalling and indicate possible roles of stalling in gene regulation.

11.
Nat Cell Biol ; 22(7): 856-867, 2020 07.
Article in English | MEDLINE | ID: mdl-32601372

ABSTRACT

The ESCRT-III membrane fission machinery maintains the integrity of the nuclear envelope. Although primary nuclei resealing takes minutes, micronuclear envelope ruptures seem to be irreversible. Instead, micronuclear ruptures result in catastrophic membrane collapse and are associated with chromosome fragmentation and chromothripsis, complex chromosome rearrangements thought to be a major driving force in cancer development. Here we use a combination of live microscopy and electron tomography, as well as computer simulations, to uncover the mechanism underlying micronuclear collapse. We show that, due to their small size, micronuclei inherently lack the capacity of primary nuclei to restrict the accumulation of CHMP7-LEMD2, a compartmentalization sensor that detects loss of nuclear integrity. This causes unrestrained ESCRT-III accumulation, which drives extensive membrane deformation, DNA damage and chromosome fragmentation. Thus, the nuclear-integrity surveillance machinery is a double-edged sword, as its sensitivity ensures rapid repair at primary nuclei while causing unrestrained activity at ruptured micronuclei, with catastrophic consequences for genome stability.


Subject(s)
Cell Nucleus/pathology , Chromatin/metabolism , Chromosome Aberrations , DNA Damage , Endosomal Sorting Complexes Required for Transport/metabolism , Genomic Instability , Membrane Proteins/metabolism , Nuclear Proteins/metabolism , Cell Nucleus/genetics , Cell Nucleus/metabolism , Chromatin/genetics , Endosomal Sorting Complexes Required for Transport/genetics , HeLa Cells , Humans
12.
J Altern Complement Med ; 24(5): 422-430, 2018 May.
Article in English | MEDLINE | ID: mdl-29356554

ABSTRACT

OBJECTIVE: To study the effect of homeopathic medicines (in higher potencies) in normal subjects, Peripheral Pulse Analyzer (PPA) has been used to record physiologic variability parameters before and after administration of the medicine/placebo in 210 normal subjects. METHODS: Data have been acquired in seven rounds; placebo was administered in rounds 1 and 2 and medicine in potencies 6, 30, 200, 1 M, and 10 M was administered in rounds 3 to 7, respectively. Five different medicines in the said potencies were given to a group of around 40 subjects each. Although processing of data required human intervention, a software application has been developed to analyze the processed data and detect the response to eliminate the undue delay as well as human bias in subjective analysis. This utility named Automatic Analysis of Intervention in the Field of Homeopathy is run on the processed PPA data and the outcome has been compared with the manual analysis. The application software uses adaptive threshold based on statistics for detecting responses in contrast to fixed threshold used in manual analysis. RESULTS: The automatic analysis has detected 12.96% higher responses than subjective analysis. Higher response rates have been manually verified to be true positive. This indicates robustness of the application software. The automatic analysis software was run on another set of pulse harmonic parameters derived from the same data set to study cardiovascular susceptibility and 385 responses were detected in contrast to 272 of variability parameters. It was observed that 65% of the subjects, eliciting response, were common. CONCLUSION: This not only validates the software utility for giving consistent yield but also reveals the certainty of the response. This development may lead to electronic proving of homeopathic medicines (e-proving).


Subject(s)
Homeopathy/methods , Monitoring, Physiologic/methods , Software , Automation , Humans , Pulse/methods
13.
J Med Eng Technol ; 41(6): 437-443, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28585476

ABSTRACT

Power spectral density (PSD) of peripheral pulses in human has been investigated in the past for its clinical applications. Continuing the efforts, data acquired using Peripheral Pulse Analyser in research projects sponsored by Board of Research in Nuclear Sciences in 207 control subjects, 18 descendants of diabetic patients and 22 patients with systemic hypertension have been subjected to PSD analysis for its study of harmonics. Application software, named Pulse Harmonic Analyser specifically developed for this work, selected 131,072 samples from each data file, obtained PSD, derived 52 PHA parameters and saved them in an Excel sheet. Coefficient of variation in control data was reduced significantly by application of Central Limit Theorem, which enabled use of parametric methods for statistical analysis of the observations. Data in hypertensive patients have shown significant difference in comparison to that of controls in eight parameters at low values of α and ß. Data in offspring of diabetic patients also have shown significant difference in one parameter indicating its usefulness in screening subjects with genetic disposition of acquiring Type-II Diabetes. PHA analysis has also yielded sub-harmonic components, which are related to combined variability in the heart rate, pulse volume and pulse morphology and has a potential to become method of choice for real time variability monitoring.


Subject(s)
Diabetes Complications/diagnosis , Diabetes Complications/physiopathology , Diagnosis, Computer-Assisted/methods , Hypertension/diagnosis , Hypertension/physiopathology , Plethysmography, Impedance/methods , Pulse Wave Analysis/methods , Adolescent , Adult , Female , Humans , Male , Mass Screening/methods , Middle Aged , Reproducibility of Results , Risk Assessment , Sensitivity and Specificity , Young Adult
14.
Luminescence ; 32(5): 772-778, 2017 Aug.
Article in English | MEDLINE | ID: mdl-27860121

ABSTRACT

A trivalent rare-earth ion (Sm3+ )-doped LiNa3 P2 O7 (LNPO) phosphor was synthesized using a conventional high-temperature solid-state reaction route. A predominant orthorhombic phase of LNPO was observed in all X-ray diffraction patterns. The surface states of the LNPO:Sm phosphor were confirmed by X-ray photoelectron spectroscopy. Under 401 nm excitation, the Sm-doped LNPO phosphors showed sharp emission peaks at 563, 600 and 647 nm that are related to the f-f transition of Sm3+ ions. The optimum concentration of Sm3+ (9 mol%) produced Commission Internationale de l'Eclairage chromaticity coordinates, color rendering index and correlated color temperature of (0.564, 0.434), 42 and 1843 K, respectively.


Subject(s)
Diphosphates/chemistry , Luminescent Agents/chemistry , Color , Diphosphates/chemical synthesis , Luminescent Agents/chemical synthesis , Luminescent Measurements , Microscopy, Electron, Scanning , Photoelectron Spectroscopy , Samarium/chemistry , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
15.
Nat Commun ; 7: 10355, 2016 Jan 13.
Article in English | MEDLINE | ID: mdl-26758068

ABSTRACT

Sam68 and T-STAR are members of the STAR family of proteins that directly link signal transduction with post-transcriptional gene regulation. Sam68 controls the alternative splicing of many oncogenic proteins. T-STAR is a tissue-specific paralogue that regulates the alternative splicing of neuronal pre-mRNAs. STAR proteins differ from most splicing factors, in that they contain a single RNA-binding domain. Their specificity of RNA recognition is thought to arise from their property to homodimerize, but how dimerization influences their function remains unknown. Here, we establish at atomic resolution how T-STAR and Sam68 bind to RNA, revealing an unexpected mode of dimerization different from other members of the STAR family. We further demonstrate that this unique dimerization interface is crucial for their biological activity in splicing regulation, and suggest that the increased RNA affinity through dimer formation is a crucial parameter enabling these proteins to select their functional targets within the transcriptome.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Alternative Splicing , DNA-Binding Proteins/metabolism , RNA-Binding Proteins/metabolism , Amino Acid Sequence , Animals , Dimerization , HEK293 Cells , Humans , Male , Mice , Molecular Sequence Data , Nucleotide Motifs , Protein Structure, Tertiary , RNA/metabolism , Structure-Activity Relationship
16.
J Nanosci Nanotechnol ; 15(2): 1280-6, 2015 Feb.
Article in English | MEDLINE | ID: mdl-26353644

ABSTRACT

Exploitation of green chemical procedures for the synthesis of metal nanoparticles by biological process has received great attention in the field of nanotechnology. To demonstrate a biogenic method that involves the reduction of aqueous gold ions by the extract of Piper longum leaves leading to the formation of different morphological gold nanoparticles (AuNPs). The formation of gold nano-structures has been characterized by UV-Vis absorption spectroscopy. The X-ray diffraction (XRD) and selected area electron diffraction (SAED) patterns indicates the AuNPs are highly crystalline nature with the face-centered cubic (111), (200), (220) and (311) facets, respectively. The AuNPs have different sizes and morphologies that are identified by TEM studies. The involvement of water soluble bio-molecules such as carboxylic acids, flavonoids, proteins and terpenoids were identified by Fourier transform infrared (FT-IR) and Raman spectrum. The responsible mechanism of improving acidic nature and the process of encapsulation of gold nanoparticles by Piper longum extract was discussed. Additionally, we have demonstrated the modified carbon paste electrode using gold nanoparticles by means of cyclic voltammetry in a solution of 1 M KCI and 1 mM [Fe(CN)6]3-/4-. The analysis of cyclic voltammetry shows electronic transmission rate between modified Au-CPE and Bare-CPE electrode increased.


Subject(s)
Gold/chemistry , Green Chemistry Technology/methods , Metal Nanoparticles/chemistry , Metal Nanoparticles/ultrastructure , Piper/chemistry , Plant Extracts/chemistry , Biological Products/chemical synthesis , Biomimetic Materials/chemical synthesis , Electric Conductivity , Excipients/chemistry , Materials Testing , Particle Size , Plant Leaves/chemistry , Surface Properties
17.
RNA ; 20(10): 1507-18, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25147239

ABSTRACT

Ribo-Seq maps the location of translating ribosomes on mature mRNA transcripts. While during normal translation, ribosome density is constant along the length of the mRNA coding region, this can be altered in response to translational regulatory events. In the present study, we developed a method to detect translational regulation of individual mRNAs from their ribosome profiles, utilizing changes in ribosome density. We used mathematical modeling to show that changes in ribosome density should occur along the mRNA at the point of regulation. We analyzed a Ribo-Seq data set obtained for mouse embryonic stem cells and showed that normalization by corresponding RNA-Seq can be used to improve the Ribo-Seq quality by removing bias introduced by deep-sequencing and alignment artifacts. After normalization, we applied a change point algorithm to detect changes in ribosome density present in individual mRNA ribosome profiles. Additional sequence and gene isoform information obtained from the UCSC Genome Browser allowed us to further categorize the detected changes into different mechanisms of regulation. In particular, we detected several mRNAs with known post-transcriptional regulation, e.g., premature termination for selenoprotein mRNAs and translational control of Atf4, but also several more mRNAs with hitherto unknown translational regulation. Additionally, our approach proved useful for identification of new transcript isoforms.


Subject(s)
Embryonic Stem Cells/metabolism , Gene Expression Regulation , Models, Theoretical , Polyribosomes/genetics , Protein Biosynthesis , RNA, Messenger/genetics , Ribosomes/genetics , Algorithms , Animals , Cells, Cultured , Embryonic Stem Cells/cytology , Genome , High-Throughput Nucleotide Sequencing , Mice , Polyribosomes/metabolism , RNA, Messenger/metabolism , Ribosomes/metabolism
18.
Indian J Surg ; 76(2): 127-30, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24891777

ABSTRACT

This study was undertaken to assess whether a routine histopathologic examination of two common surgical specimens (appendix and gallbladder) is needed and whether routine histopathologic examination has an impact on further management of patients. Histopathology reports of patients who had undergone appendicectomy and cholecystectomy, between 2006 and 2010, were analyzed retrospectively in the department of pathology of a tertiary care hospital. The case notes were retrieved in all cases of malignancies. Patients having a clinical diagnosis or suspicion of malignancy were excluded. The incidence and impact of unexpected pathologic diagnosis on postoperative management were noted. The study period included a total of 1,123 and 711 appendicectomy and cholecystectomy specimens, respectively. Fifteen (1.336 %) cases of appendicectomy specimens revealed incidental unexpected pathological diagnoses, which included tubercular appendicitis (n = 2), parasite (n = 8), neuroma (n = 1), carcinoid (n = 2), pseudomyxoma (n = 1), and adenocarcinoma (n = 1). About 88 % of such unexpected appendiceal findings had an impact on postoperative treatment. Unexpected pathologic gallbladder findings were found in 12 (1.68 %) of 711 cholecystectomy specimens. In 6 (0.84 %) cases, gallbladder cancer (GBC) was detected. Additional further management was required in 50 % of patients with unexpected gallbladder findings. Twenty of the total 1,834 specimens (1.090 %) had an impact on patient management or outcome and were not suspected on macroscopic examination at the time of surgery. These would have been missed had the specimens not been examined microscopically. The intraoperative diagnosis of the surgeon is therefore sometimes doubtful in detecting abnormalities of the appendix and gallbladder. This study supports the sending of all appendicectomy and cholecystectomy specimens for routine histopathological examination. Appendix and gallbladder should undergo routine histopathological examination. This is important in patients with advanced age and gallstones. Also, it is of great value in identifying unsuspected conditions which require further postoperative management. Selectively sending specimens for histopathological examination can result in reduced workload on the histopathology department without compromising patient safety.

20.
PLoS One ; 6(12): e29088, 2011.
Article in English | MEDLINE | ID: mdl-22194994

ABSTRACT

Androgens drive the onset and progression of prostate cancer (PCa) by modulating androgen receptor (AR) transcriptional activity. Although several microarray-based studies have identified androgen-regulated genes, here we identify in-parallel global androgen-dependent changes in both gene and alternative mRNA isoform expression by exon-level analyses of the LNCaP transcriptome. While genome-wide gene expression changes correlated well with previously-published studies, we additionally uncovered a subset of 226 novel androgen-regulated genes. Gene expression pathway analysis of this subset revealed gene clusters associated with, and including the tyrosine kinase LYN, as well as components of the mTOR (mammalian target of rapamycin) pathway, which is commonly dysregulated in cancer. We also identified 1279 putative androgen-regulated alternative events, of which 325 (∼25%) mapped to known alternative splicing events or alternative first/last exons. We selected 30 androgen-dependent alternative events for RT-PCR validation, including mRNAs derived from genes encoding tumour suppressors and cell cycle regulators. Of seven positively-validating events (∼23%), five events involved transcripts derived from alternative promoters of known AR gene targets. In particular, we found a novel androgen-dependent mRNA isoform derived from an alternative internal promoter within the TSC2 tumour suppressor gene, which is predicted to encode a protein lacking an interaction domain required for mTOR inhibition. We confirmed that expression of this alternative TSC2 mRNA isoform was directly regulated by androgens, and chromatin immunoprecipitation indicated recruitment of AR to the alternative promoter region at early timepoints following androgen stimulation, which correlated with expression of alternative transcripts. Together, our data suggest that alternative mRNA isoform expression might mediate the cellular response to androgens, and may have roles in clinical PCa.


Subject(s)
Androgens/pharmacology , Exons/genetics , Gene Expression Profiling , Genome, Human/genetics , Prostatic Neoplasms/genetics , Signal Transduction/drug effects , Transcriptome/genetics , Cell Line, Tumor , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Epithelial Cells/pathology , Gene Expression Regulation, Neoplastic/drug effects , Genes, Neoplasm/genetics , Humans , Ligands , Male , Promoter Regions, Genetic/genetics , Prostatic Neoplasms/pathology , RNA Isoforms/genetics , RNA Isoforms/metabolism , Receptors, Androgen/metabolism , Signal Transduction/genetics , Tuberous Sclerosis Complex 2 Protein , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism
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