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Biomedicine & Pharmacotherapy =... Sep 2021Cancer recurrence poses a significant challenge. At the cellular level, recurrence takes place as a result of reactivation of dormant cancer cells residing at G phase....
Cancer recurrence poses a significant challenge. At the cellular level, recurrence takes place as a result of reactivation of dormant cancer cells residing at G phase. The aim of the study was to identify compounds that can trap prostate and lung cancer cells in G phase from a new Chinese herb recipe, Astringent recipe, consisting of Radix Paeoniae Alba, Agrimonia pilosa Ledeb, Fructus Mume, Fritillaria thunbergii Miq., Ganoderma Lucidum Karst, and Astragalus membranaceus (Fisch.) Bunge. Astringent recipe impeded cell cycle progression in prostate and lung cancer cells by rounding them up at G phase by flow cytometric analysis of cancer cells stained with Hoechst 33342 and Pyronin Y, respectively, for DNA and RNA. The anti-cancer efficacy of the recipe was found to be attributable to Agrimonia pilosa Ledeb. Further study established that agrimol B, a polyphenol derived from Agrimonia pilosa Ledeb, contributed to the activity of the herb. The action of agrimol B on the cancer cells was likely derived from its effect on c-MYC, SKP2 and p27 by immunoblotting and immunofluorescence. Oral administration of Agrimonia pilosa Ledeb or agrimol B reduced growth of prostate cancer cell xenograft in animal. In conclusion, Agrimol B can enrich for prostate and lung cancer cells in G state and influence key regulators that govern G status.
Topics: A549 Cells; Agrimonia; Animals; Antineoplastic Agents, Phytogenic; Butanones; Cell Cycle Checkpoints; Dose-Response Relationship, Drug; Ellagic Acid; G1 Phase Cell Cycle Checkpoints; HEK293 Cells; Humans; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Phenols; Plant Extracts; Tumor Burden
PubMed: 34098217
DOI: 10.1016/j.biopha.2021.111795 -
The Journal of Experimental Medicine Aug 1949Following the injection of various antigenic and non-antigenic materials into the foot-pads of rabbits, the draining (popliteal) lymph nodes were removed on successive...
Following the injection of various antigenic and non-antigenic materials into the foot-pads of rabbits, the draining (popliteal) lymph nodes were removed on successive days and studied histologically, chemically, and serologically. On the 2nd day after injection of antigen, nucleoli and cytoplasmic granules and crescents stained with pyronine began to appear. They were found first in somewhat altered reticulum cells, later in transitional forms, then in young lymphocytes, and finally in more mature lymphocytes. The identity of this pyronine-stained material as ribonucleic acid was demonstrated by specific digestion with protease-free ribonuclease. The concentration of ribonucleic acid was determined in aqueous extracts of the lymph nodes. It was observed that the concentration had risen to more than twice its normal value by the 2nd to 5th day following the injection of antigens into the foot, and then it declined. The peak of this change occurred at or slightly before the appearance of the maximal concentration of antibodies in the same node. Non-antigenic materials, when injected into the foot, did not give rise to an increase in the ribonucleic acid content of the lymph node. The concentration of desoxyribonucleic acid was constant in all lymph nodes, within the limits of experimental variation.
Topics: Animals; Antibodies; Antigens; DNA; Lymph Nodes; Lymphocytes; RNA; Rabbits
PubMed: 18136196
DOI: 10.1084/jem.90.2.169 -
Antimicrobial Agents and Chemotherapy Feb 2008We have identified a second resistance-nodulation-cell division (RND)-type efflux pump, AdeIJK, in clinical isolate Acinetobacter baumannii BM4454. The adeI, adeJ, and...
We have identified a second resistance-nodulation-cell division (RND)-type efflux pump, AdeIJK, in clinical isolate Acinetobacter baumannii BM4454. The adeI, adeJ, and adeK genes encode, respectively, the membrane fusion, RND, and outer membrane components of the pump. AdeJ belongs to the AcrB protein family (57% identity with AcrB from Escherichia coli). mRNA analysis by Northern blotting and reverse transcription-PCR indicated that the genes were cotranscribed. Overexpression of the cloned adeIJK operon was toxic in both E. coli and Acinetobacter. The adeIJK genes were detected in all of the 60 strains of A. baumannii tested. The two latter observations suggest that the AdeIJK complex might contribute to intrinsic but not to acquired antibiotic resistance in Acinetobacter. To characterize the substrate specificity of the pump, we have constructed derivatives of BM4454 in which adeIJK (strain BM4579), adeABC (strain BM4561), or both groups of genes (strain BM4652) were inactivated by deletion-insertion. Determination of the antibiotic susceptibility of these strains and of BM4652 and BM4579, in which the adeIJK operon was provided in trans, indicated that the AdeIJK pump contributes to resistance to beta-lactams, chloramphenicol, tetracycline, erythromycin, lincosamides, fluoroquinolones, fusidic acid, novobiocin, rifampin, trimethoprim, acridine, safranin, pyronine, and sodium dodecyl sulfate. The chemical structure of these molecules suggests that amphiphilic compounds are the preferred substrates. The AdeABC and AdeIJK efflux systems contributed in a more than additive fashion to tigecycline resistance.
Topics: Acinetobacter baumannii; Anti-Bacterial Agents; Bacterial Proteins; Cloning, Molecular; Drug Resistance, Bacterial; Drug Resistance, Multiple, Bacterial; Humans; Membrane Transport Proteins; Microbial Sensitivity Tests; Molecular Sequence Data; Multigene Family; Sequence Analysis, DNA; Substrate Specificity
PubMed: 18086852
DOI: 10.1128/AAC.00732-07 -
Experimental Hematology Sep 2007Although increased expression of CD38 on the surface of human CD34(+) cells is associated with differentiation, we reported recently that both lineage-negative (Lin(-))...
OBJECTIVE
Although increased expression of CD38 on the surface of human CD34(+) cells is associated with differentiation, we reported recently that both lineage-negative (Lin(-)) CD34(+)CD38(-) and Lin(-)CD34(+)CD38(lo) fractions of cord blood contain primitive severe combined immunodeficient (SCID)-repopulating cells (SRC). Thus, it is important to determine if a hierarchical relationship exists between the SRC from these two populations or if CD38 is reversibly expressed.
MATERIALS AND METHODS
To determine if SRC from the CD34(+)CD38(-) and CD34(+)CD38(lo) cell fractions could generate SRC of the same and/or alternate CD38 expression, cells from primary nonobese diabetic/SCID mice transplanted with CD34(+)CD38(-) cells were resorted into both CD34(+)CD38(-) and CD34(+)CD38(lo) fractions and injected into separate secondary recipients, which were evaluated for human cell engraftment 7 to 10 weeks later. As primary mice transplanted with CD34(+)CD38(lo) cells also contained cells of both immunophenotype, these cells were also resorted and transplanted into separate secondary recipients. The cell-cycle status of various CD34(+) SRC fractions were evaluated using Hoechst 33342 and Pyronin Y staining in order to determine if CD38 expression was coordinated with divisional activation.
RESULTS
Each cell fraction obtained from primary recipients was able to reconstitute secondary mice, indicating that CD38 expression reversibly oscillates between negative and low levels on CD34(+) repopulating cells. CD38 expression on repopulating cells correlated with a transition between the G(0) and G(1) phases of the cell cycle.
CONCLUSION
CD38 is reversibly expressed on CD34(+) SRC between negative and low levels and corresponds to a change in the cell-cycle state. These observations establish a foundation to uncover the molecular program of stem cell regulation and underscore the importance of functional assessments when isolating and characterizing human hematopoietic stem cells.
Topics: ADP-ribosyl Cyclase 1; Animals; Antigens, CD34; Cell Culture Techniques; Cell Cycle; Hematopoiesis; Hematopoietic Stem Cell Transplantation; Hematopoietic Stem Cells; Humans; Mice; Mice, SCID; Receptors, Cell Surface; Transplantation, Heterologous
PubMed: 17656009
DOI: 10.1016/j.exphem.2007.05.017 -
ACS Omega Sep 2023Membrane-permeable fluorescent dyes that stain DNA are useful reagents for microscopic imaging, as they can be introduced into living cells to label DNA. However, the...
Membrane-permeable fluorescent dyes that stain DNA are useful reagents for microscopic imaging, as they can be introduced into living cells to label DNA. However, the number of these dyes, such as Hoechst 33342, is limited. Here, we show that the icosahedral dodecaborate BBr, a superchaotropic carrier that delivers different types of molecules into cells, functions as an excellent carrier for membrane-impermeable fluorescent dyes. Propidium iodide (PI) and 4',6-diamidino-2-phenylindole (DAPI), dicationic membrane-impermeable fluorescent dyes that stain DNA, can permeate cell membranes in the presence of boron clusters. Methyl green (MG), a dicationic dye used in the histological and fluorescent staining of DNA, permeated cell membranes in the presence of boron clusters. In contrast, monocationic membrane-permeable fluorescent dyes, such as acridine orange and pyronin Y, exhibited reduced fluorescence in cells in the presence of boron clusters. Boron clusters do not quench dicationic fluorescent dyes in water in vitro but have quenching effects on monocationic fluorescent dyes. We have demonstrated that the addition of BBr to impermeable dicationic fluorescent DNA-staining dyes, such as DAPI, PI, and MG, which have been widely used for numerous years, imparts membrane permeability to introduce these dyes into living cells.
PubMed: 37779949
DOI: 10.1021/acsomega.3c05156 -
Journal of Bacteriology Apr 2000Genes (ebrAB) responsible for ethidium resistance were cloned from chromosomal DNA of Bacillus subtilis ATCC 9372. The recombinant plasmid produced elevated resistance...
Genes (ebrAB) responsible for ethidium resistance were cloned from chromosomal DNA of Bacillus subtilis ATCC 9372. The recombinant plasmid produced elevated resistance against ethidium bromide, acriflavine, pyronine Y, and safranin O not only in Escherichia coli but also in B. subtilis. It also caused an elevated energy-dependent efflux of ethidium in E. coli. EbrA and EbrB showed high sequence similarity with members of the small multidrug resistance (SMR) family of multidrug efflux pumps. Neither ebrA nor ebrB was sufficient for resistance, but introduction of the two genes carried on different plasmids conferred drug resistance. Thus, both EbrA and EbrB appear to be necessary for activity of the multidrug efflux pump. In known members of the SMR family, only one gene produces drug efflux. Thus, EbrAB is a novel SMR family multidrug efflux pump with two components.
Topics: Acriflavine; Antiporters; Bacillus subtilis; Biological Transport, Active; Cloning, Molecular; Drug Resistance, Microbial; Drug Resistance, Multiple; Escherichia coli; Escherichia coli Proteins; Ethidium; Genes, Bacterial; Membrane Proteins; Microbial Sensitivity Tests; Molecular Sequence Data; Phenazines; Pyronine; Sequence Analysis, DNA
PubMed: 10735876
DOI: 10.1128/JB.182.8.2307-2310.2000 -
The Journal of Cell Biology May 1962Chromosome segments of urodele cells lose some substance after irradiation with about 10(-1) ergs/micro(2) of heterochromatic ultraviolet light. These segments stain...
Chromosome segments of urodele cells lose some substance after irradiation with about 10(-1) ergs/micro(2) of heterochromatic ultraviolet light. These segments stain faintly or negatively with the Feulgen and pyronine-methyl-green methods and weakly with the Alfert-Gesch-wind stain for basic protein. In the living cells, Perry found in these chromosome segments a decrease of 50 to 60 per cent in absorption at 2400, 2600, and 2800 A, i.e., in the region of intense chromosomal absorption that is maximal at 2600 A. Apparently the material lost contains DNA (?DNP) and we call the process DNA-steresis. In such cells, fixed in neutral formalin in Tyrode's solution and stained with phosphotungstic acid, electron microscopy shows that the unirradiated parts of the chromosomes consist of (a) a homogeneous or finely fibrillar material (component-A) filling the meshes of (b) an irregular network with bars 40 to 300 A in diameter, some of which continue into a similar interchromosomal network. DNA-steretic portions of the chromosomes consist mainly of this network and only small amounts of component-A, which presumably contains the DNA. We have not been able to demonstrate DNA-steresis with the electron microscope after primary fixation with OsO(4) or KMnO(4). Structural changes due to DNA-steresis are compared with certain nuclear changes in the mitotic cycle.
Topics: Chromosomes; DNA; Electrons; Microscopy; Microscopy, Electron; Mitosis; Staining and Labeling; Ultraviolet Rays
PubMed: 13870145
DOI: 10.1083/jcb.13.2.269 -
Antimicrobial Agents and Chemotherapy Mar 2000Kidney cortex apoptosis was studied with female Wistar rats treated for 10 days with gentamicin and netilmicin at daily doses of 10 or 20 mg/kg of body weight and...
Kidney cortex apoptosis was studied with female Wistar rats treated for 10 days with gentamicin and netilmicin at daily doses of 10 or 20 mg/kg of body weight and amikacin or isepamicin at daily doses of 40 mg/kg. Apoptosis was detected and quantitated using cytological (methyl green-pyronine) and immunohistochemical (terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling) staining, in parallel with a measurement of drug-induced phospholipidosis (cortical phospholipids and phospholipiduria), cortical proliferative response ((3)H incorporation in DNA and histoautoradiography after in vivo pulse-labeling with [(3)H]thymidine), and kidney dysfunction (blood urea nitrogen and creatinine). Gentamicin induced in proximal tubules a marked apoptotic reaction which (i) was detectable after 4 days of treatment but was most conspicuous after 10 days, (ii) was dose dependent, (iii) occurred in the absence of necrosis, and (iv) was nonlinearly correlated with the proliferative response (tubular and peritubular cells). Comparative studies revealed a parallelism among the extents of phospholipidosis, apoptosis, and proliferative response for three aminoglycosides (gentamicin >> amikacin congruent with isepamicin). By contrast, netilmicin induced a marked phospholipidosis but a moderate apoptosis and proliferative response. We conclude that rats treated with gentamicin develop an apoptotic process as part of the various cortical alterations induced by this antibiotic at low doses. Netilmicin, and still more amikacin and isepamicin, appears safer in this respect. Whereas a relation between aminoglycoside-induced tubular apoptosis and cortical proliferative response seems to be established, no simple correlation with phospholipidosis can be drawn.
Topics: Amikacin; Animals; Anti-Bacterial Agents; Apoptosis; Blood Urea Nitrogen; Cell Division; Creatinine; Female; Gentamicins; In Situ Nick-End Labeling; Kidney Cortex; Kidney Tubules, Proximal; Netilmicin; Phospholipids; Rats; Rats, Wistar
PubMed: 10681336
DOI: 10.1128/AAC.44.3.665-675.2000 -
Chemical Science Jul 2022Charge transfer (CT) interaction induced formation of a hierarchical supramolecular assembly has attracted attention due to its wide diversity of structural and...
Hierarchical supramolecular co-assembly formation employing multi-component light-harvesting charge transfer interactions giving rise to long-wavelength emitting luminescent microspheres.
Charge transfer (CT) interaction induced formation of a hierarchical supramolecular assembly has attracted attention due to its wide diversity of structural and functional characteristics. In the present work, we report the generation of green luminescent microspheres from the charge transfer interaction induced co-assembly of a bis-naphthyl dipicolinic amide (DPA) derivative with tetracyanobenzene (TCNB) for the first time. The properties of these self-assemblies were studied both in solution and the solid-state using spectroscopic and a variety of microscopy techniques. The X-ray crystal structure analysis showed a mixed stack arrangement of DPA and TCNB. The molecular orbital and energy level calculations confirm the charge transfer complex formation between DPA and TCNB. Furthermore, energy transfer was observed from the green luminescent CT complex to a red-emitting dye, pyronin Y, in the microsphere matrix, leading to the formation of a light-harvesting tri-component self-assembly.
PubMed: 35865882
DOI: 10.1039/d2sc02097a -
Cytometry Mar 1987Chinese hamster ovary (CHO) cells or isolated nuclei were stained with pyronin Y(PY) and analyzed by absorption or fluorescence microscopy, as well as by flow cytometry....
Chinese hamster ovary (CHO) cells or isolated nuclei were stained with pyronin Y(PY) and analyzed by absorption or fluorescence microscopy, as well as by flow cytometry. Specificity of the staining reaction was assayed by testing sensitivity of the stainable material to RNase or DNase. The colored complexes detected by light absorption in fixed cells stained with PY are nonfluorescent and are most likely the products of condensation of single-stranded (ss) RNA by PY; the poly(rA) and poly(rA,rG) are the most sensitive to condensation. The products of PY interaction with double-stranded (ds) nucleic acids are fluorescent and can be detected in cells by cytofluorometry. PY used alone stains both DNA and RNA, and the staining capabilities of these nucleic acids vary depending upon the PY concentration at equilibrium; at a concentration above 330 microM, the RNA stainability decreases, perhaps due to its denaturation and condensation caused by the dye. In the presence of Hoechst 33342, PY can specifically stain RNA in fixed cells or isolated cell nuclei. Because only complexes of PY with ds RNA are fluorescent, this dye can be used as a probe of RNA conformation, e.g., to monitor denaturation of RNA in situ. The RNA stainability of mitotic cells is about 25% lower than that of cells in G2 phase, which indicates that during mitosis proportionately less cellular RNA is in the ds conformation. The advantages and limitations of the two cytochemical methods for DNA/RNA detection, one based on the use of Hoechst 33342 and PY, and another employing the metachromatic properties of acridine orange, are compared.
Topics: Animals; Benzimidazoles; Cell Cycle; Cell Line; Cell Nucleus; Cricetinae; DNA; Flow Cytometry; Histocytochemistry; Microscopy, Fluorescence; Nucleic Acid Conformation; Nucleic Acids; Proteins; Pyronine; RNA; Xanthenes
PubMed: 2438101
DOI: 10.1002/cyto.990080206