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PubMed1981

Effects of the resin and smoke condensate of Cannabis sativa on the oestrous cycle of the rat.

This study is concerned with variations in the oestrous cycle of the Sprague-Dawley rat following the intraperitoneal administration of maize oil solutions of Cannabis sativa resin and smoke condensate in doses of 10 and 20 mg/kg. Oestrus was shortened with doses of both the resin and the smoke condensate, whereas dioestrus was lengthened with the 20 mg/kg smoke condensate. ALso observed was a lengthening of postoestrus following the administration of 20 mg/kg of either the resin or the smoke condensate.

Animals↗

PubMedDate not supplied

[Psychoanalytic process between the Scylla of "condensation" and the Charybdis of "systematic acoustic deficit." Introduction to a research project].

Both for research and for training in psychoanalysis psychoanalytic dialogues must be made publicly accessible. With traditional procedures (supervision, case seminars, publications) condensations are inevitable, for which, however, no binding rules exist. Empirical research results are quoted to show that these condensations are highly selective. We cannot see any immediately plausible external criteria to decide which kinds of selective condensations are justified and which are not. Heimann's conceptualisations of the three "positions" within which psychoanalysts function as therapists is introduced to explain why analysts especially fail to report their own interpretations. If one tries to evade the devil of selective condensation by audio-recording, one falls into the deep blue sea of the "systematic acoustic deficit". Of the "running commentary" within the analyst only the small part which is uttered as therapeutic intervention can be registered acoustically. From a discussion of the problems analysts and patients experience with audiorecordings it is argued that the analyst/patient dyads consenting to this procedure are a systematic sample and thus not representative for the total of analysts and their patients. Finally a research program is presented which tries to partly fill the systematic acoustic deficit by gathering "proning retrospectives". The latter are spoken by the analyst after each "proning" (= session) on the same cassette which recorded the therapy. In a free part the analyst free associates. In a second, the "intervention explication" part the analyst identifies roughly 3 "important" interventions and tries to formulate for each its source, its purpose and the point in time when he had conceived his formulation. An evaluation design for thus gathered information is described.

Communication↗

PubMed1994

Oxidative damage to the eye lens caused by cigarette smoke and fuel smoke condensates.

Cigarette smoking is reported to increase the risk of cataract. Likewise, the use of smoky cooking fuel is implicated in the etiology of cataract. In an effort to understand the cellular and molecular basis, the in vitro and in vivo cataractogenetic effects of these smoke condensates have been studied using isolated rat lenses and pigmented rats. Isolated capsulated rat lenses are incubated with cigarette smoke condensate (CSC) and firewood smoke condensate (FSC) for varying periods, with and without antioxidants, in the presence and absence of light. CSC and FSC permeate the lens capsule, impart colour and opacify the lens in a light- and dose-dependent manner. Antioxidants offer partial inhibition against the above damage. The condensates contain polycyclic aromatics which generate reactive oxygen species such as O2 photodynamically, and ppb levels of Fenton metal ions which induce oxidative reactions through .OH. Smoke induced damage possibly occurs through systemic absorption and transport of toxic components to several tissues, and specially into the lens, wherein the turnover is slow, leading to chronic accumulation causing oxidative damage to the constituent molecules and to consequent lenticular opacity.

Animals↗

PubMed1993

Comparison of total DNA adduct levels induced in mouse tissues and human skin by mainstream and sidestream cigarette smoke condensates.

Cigarette smoke condensates (CSCs) of both mainstream (MS) and sidestream (SS) smoke were used to treat mice topically in equivalent amounts. Human skin maintained in short-term culture was also treated with the condensates. DNA adducts, induced by the CSCs and detected by the nuclease P1 method of 32P-postlabelling, were quantified in a number of murine tissues and in the human skin DNA. In the five mouse tissues studied both MS-CSC and SS-CSC produced characteristic diagonal radioactive zones on TLC, indicative of the formation of multiple DNA adducts. In three tissues (skin, lung and kidney), SS-CSC induced greater total adduct levels than MS-CSC (statistically significant in skin and kidney, p < 0.05). However, greater adduct levels induced by MS-CSC were recorded for heart and bladder DNA (not statistically significant). Similar results to those found in mouse skin were obtained with human skin; SS-CSC induced a approximately 2-fold greater level of DNA adducts than MS-CSC (p < 0.05). Incubation of DNA directly with condensates in vitro demonstrated that DNA adducts could be formed without an exogenous metabolizing system. This direct interaction of condensates with DNA occurred at similar levels for both MS- and SS-CSC, although inclusion of an oxygen radical-generating system enhanced the SS-CSC binding to a greater extent than that of the MS-CSC.

Animals↗

PubMed1996

Topoisomerase II inhibitors affect entry into mitosis and chromosome condensation in BHK cells.

DNA topoisomerase II (topo II) is required at mitosis in yeast for high chromosome condensation and for chromosome segregation. Recent studies on intact mammalian cells using topo II inhibitors that do not stabilize cleavable complexes also suggest a requirement for topo II for complete chromosome condensation and perhaps also for entry into mitosis. We have investigated the effects of merbarone, ICRF-187, and aclarubicin, three topo II inhibitors that do not stabilize the cleavable complex, on entry into mitosis and on chromosome condensation in BHK and in tsBN2 cells. We have compared their effects with those of etoposide, a topo II inhibitor that stabilizes the cleavable complex. All inhibitors induced a concentration-dependent G2 delay or arrest that could be overcome with fostriecin or okadaic acid or by inactivation of RCC1 in tsBN2 cells. Mitotic chromosomes from cells treated with etoposide were extensively fragmented, whereas mitotic chromosomes from cells treated with merbarone, ICRF-187, or aclarubicin were intact but elongated and tangled. These results provide strong evidence that topo II activity is required in chromosome condensation for final coiling of the chromatids. Our results also indicate that protein phosphatases and RCC1 play a role in G2 delay induced by all inhibitors, whether they do or do not stabilize the cleavable complex.

Aclarubicin↗

PubMedDate not supplied

Wood-drying condensate from Eastern white pine induced cytotoxicity and genotoxicity in vitro.

Eastern white pine is one of the most important commercial species of wood in the Northeast. Condensates extracted from this wood were tested to detect potential cytotoxicity and genotoxicity in Chinese Hamster Ovary (CHO) cells in the absence of S-9 activation. Cytotoxicity was measured by the Trypan blue exclusion assay, mitotic index (MI) and proliferative rate index (PRI). Genotoxicity was measured by the chromosome aberration (CA) assay and sister chromatid exchange (SCE) analysis. Both cytotoxic and genotoxic effects were observed. Laboratory-generated Eastern white pine condensate reduced the viability of CHO cells. The number of viable cells was roughly inversely proportional to dosage over a range of 91 percent to 58 percent survival in treated groups as compared to 2.4 x 10(5) viable cells (100 percent) in the control. The mitotic index (MI) data also showed an inverse correlation with dosage. The highest scorable dose limited by toxicity was determined to be 1 ml of Eastern white pine condensate in a total of 10 ml of medium. Lastly, a dose response curve was observed using the CA assay and also with the SCE analysis. The present findings support results obtained from Ames testing of Eastern white pine condensate and also corroborate results derived from human peripheral-blood lymphocytes.

Animals↗

PubMed1997

[Breath condensate as a method of noninvasive assessment of inflammation mediators from the lower airways].

The detection of mediators from the lower airways still depends on invasive or provoking sampling techniques like bronchoalveolar lavage (BAL) or induced sputum, respectively. Both methods affect the specimen itself. In contrast, the breathing condensate opens the possibility to get native specimens from lower airways during breathing at rest. The breathing condensate was obtained by freezing of exhaled air. The equipment was developed in the FILT Res. Soc. Ltd.. The method is applied for a patent. Leukotriene B4 and Leukotriene C4D4E4F4 were measured in the exhalation of asthmatics, patients with different airway disorders and healthy volunteers. In an additional study the condensate was obtained before and after of a non-specific bronchial challenge test. In asthmatics a close correlation between leukotriene concentration of the condensate and the degree of asthmatic disease according to "International Consensus Report" was found, but no correlation to lung function tests. Within a bronchial challenge test applying histamine the release of leukotrienes was shown to be more sensitive to the challenge test than a lung function test. The results of the study indicate new diagnostic possibilities in lung diseases using the detection of non volatile substances in the exhaled air.

Asthma↗

PubMed1995

Comparison of thermoplasticized gutta-percha root canal obturation technique to the lateral condensation.

This in vitro study compared the quality of filling the root canal by the conventional lateral condensation technique to the fill by the commercially available thermoplasticized gutta-percha method. Subjective radiographic evaluation of density, presence of voids, and extent of fill were made for each of the 20 freshly extracted maxillary central incisors used for this study. Voids were noted in 10% of the laterally condensed canals, versus 40% of those obturated with the thermoplasticized gutta-percha. The mean time (in seconds) to obturate the canals with lateral condensation was 387 (s = 112); of the experimental was 145 (s = 23). We conclude that thermoplastisizing and injecting the gutta-percha into the root canal was a fast and a relatively easy technique, but the resultant filling was no more dense, and was shorter apically than the laterally condensed gutta-percha.

Chi-Square Distribution↗

PubMed2026

Stem Cell Differentiation Disperses Transcriptional Clusters via a Conserved Surface-Condensate Trajectory.

Stem cells exhibit exceptionally prominent transcriptional clusters, which dissolve with progressing differentiation. Although these clusters are assigned central roles in embryonic gene regulation, their formation and loss during differentiation remain poorly understood. This study reveals that these prominent clusters disperse along a conserved trajectory in mouse embryonic stem cells, fruit fly testes, and zebrafish embryos. Imaging and lattice simulations show that these clusters form via surface condensation on H3K27ac-marked super-enhancer regions, which act as genomic scaffolds. Upon differentiation, partial loss of these active epigenetic marks and transcription-driven unfolding lead to dispersal of the prominent clusters. The block copolymer-based lattice simulations explain this process as a conserved trajectory through a three-dimensional state space, governed by surface condensation principles that extend beyond canonical liquid-liquid phase separation. This work marks surface condensation as a biophysical mechanism for the dynamic organization of stem cell-specific transcriptional hubs and demonstrates evolutionary conservation in several organisms. By uncovering a conserved biophysical mechanism for transcriptional organization in development, our work illustrates how polymer properties can contribute to the control of cell identity and fate.

Animals↗

PubMed2025

The small bacterial membrane protein YohP induces nucleoid condensation in E. coli and inhibits oligomerization of antimicrobial peptides.

Prokaryotic organisms execute multiple stress response mechanisms in order to cope with rapidly changing environments. Some mechanisms respond to specific cues, such as the OxyR-dependent response to hydrogen peroxide or the SOS-response that is induced upon DNA-damage. These specific responses complement general mechanisms that respond to multiple and diverse stressors. One example is nucleoid condensation, which is a rapid and effective mechanism for genome protection and observed in response to various stresses, including entry into stationary phase. Recently, the upregulation of small membrane proteins (SMPs) in response to stress was observed, but details on how this emerging class of proteins modulate the stress response is largely unknown. Here, we demonstrate that the production of two SMPs, YohP and YncL, cause nucleoid condensation in Escherichia coli. Nucleoid condensation is the result of YohP-/YncL-induced sublethal membrane depolarization, which induces the phage-shock response and leads to a reduction of global protein synthesis. YohP production also prevents the oligomerization of the antimicrobial peptide magainin-2 in the E. coli membrane and reduces the metabolic activity of E. coli cells. Thus, the synthesis of YohP and likely of other SMPs potentially protects bacterial cells against some unfavorable conditions by shifting them into a metabolically silent state.

YncL↗

PubMed2003

Increased detection rate of glaucomatous visual field damage with locally condensed grids: a comparison between fundus-oriented perimetry and conventional visual field examination.

OBJECTIVE: To compare detection rates of glaucomatous visual field defects (VFDs) between the conventional 6 degrees x 6 degrees stimulus grid and locally condensed target arrangements in morphologically suspicious regions. METHODS: A total of 66 eyes of 66 patients with glaucoma or patients suspected of having glaucoma (34 females and 32 males; age range, 14-85 years) were enrolled in this study. Individual, local target condensation was realized by fundus-oriented perimetry (FOP) using a campimeter and compared with the results of conventional automated perimetry (CAP), obtained with the Humphrey Field Analyzer (30-2 grid). RESULTS: Twenty-three of the 66 patients showed normal findings with both methods; 27 had concordantly pathological results. In 15 patients we obtained normal findings with CAP, whereas FOP revealed early glaucomatous VFDs. Only one patient showed VFDs with CAP, whereas FOP results were normal. Scotoma detection rates significantly differed between the 2 methods (P<.001, sign test). Test duration with FOP was more than doubled compared with CAP. When considering only FOP points coinciding with the 6 degrees spacing of the 30-2 grid, there was no longer a significant difference between FOP and CAP (P>.25, sign test). This indicated that the target pattern, rather than the perimetric device, was most relevant for detecting glaucomatous VFDs. Follow-up throughout a series of 3 subsequent sessions at 6-month intervals revealed repeatable results in more than two thirds of all eyes for both FOP and CAP. CONCLUSIONS: Fundus-oriented perimetry that uses individually condensed test grids significantly increases the detection rate of glaucomatous VFDs in morphologically conspicuous areas compared with CAP using equidistant (6 degrees x 6 degrees) target arrangements. Repeatability is comparable between both methods.

Adolescent↗

PubMed1997

Apoptotic condensations in M-phase cells.

BACKGROUND: Apoptosis is a morphologically distinctive form of programmed cell death/cell suicide in which genomic DNA degradation/fragmentation and variegated dense chromatin aggregates are characteristic hallmarks that have never been demonstrated in mitotic cells. Perceptions of mutual exclusivity between apoptosis and mitosis imply that M-phase cells cannot be apoptotic. However, in the present study we show apoptotic morphologies in M-phase cells after an acute oxidative stress and endonuclease digestion. METHODS: Degradation of genomic DNA in human Chang liver cells (American Type Culture Collection, ATCC CCL13) was demonstrated by flow cytometric cell-by-cell evaluation of (a) propidium iodide intercalative binding to DNA and (b) terminal deoxynucleotidyl transferase (TdT)-mediated 3'OH nick end labeling (TUNEL) of fragmented DNA. Oxidative stress was imposed by a 30-min prepulse with 200 microM vanadyl(4), which produces hydroxyl free radicals (OH*), the most reactive of the free radical species. Oxidative stress in the cells was demonstrated by evaluating glutathione-S-transferase (GST)-mediated monochlorobimane-glutathione adduct fluorescence for glutathione content, the main reducing agent of a cell, and methylene blue redox metachromasia, which is a deep color when oxidized and colorless when reduced. Cells with DNA fragmentation were highlighted by TUNEL. Apoptotic morphologies were visualized by staining with Giemsa and neutral red dyes and by DNA-propidium iodide binding to chromatin. Direct endonuclease induction of apoptotic morphologies in permeabilized M-phase cells was produced by 1 hr incubation (37 degrees C) with 16 units/ml of micrococcal nuclease. RESULTS: The genomic DNA of proliferative cells, namely in G2/M phase of the cell cycle, was degraded by vanadyl(4) prepulsing and by micrococcal nuclease digestion, concomitantly with DNA fragmentation shown by TUNEL. Cytological profiles showed GSH depletion and M-phase cells with particularly high oxidative reactivity indicated by methylene blue redox metachromasia. DNA fragmentation in M-phase cells was highlighted by TUNEL. Characteristic apoptotic condensations, ranging from single-ball condensations to "pulverized" aggregates of a mitotic catastrophe, buddings, and "apoptotic bodies," were found in prophase, metaphase, anaphase, and telophase mitotic cells. The observed separation of condensed chromatin aggregates from the main chromosome mass in prophase and metaphase cells could explain micronuclei, linking it with apoptosis. Direct endonuclease digestion readily produced apoptotic morphologies in interphase and in M-phase cells. CONCLUSION: Apoptotic morphologies in M-phase cells can be induced indirectly via oxidative stress or directly via endonuclease activity, which has long been established as a pervading hallmark of apoptosis.

Apoptosis↗

PubMed1996

Induction of micronuclei in cultured mammalian cells by fume condensates of roofing asphalt.

A considerable number of workers in the United States are employed in asphalt industries and are potentially exposed to asphalt fumes. The information regarding the potential carcinogenic hazards of such fumes to exposed workers is still limited. Studies have been conducted to determine the cytogenetic effects of roofing asphalt fume using cultured mammalian cells. Exponentially growing Chinese hamster lung fibroblasts (V79 cells) were exposed to different concentrations of condensates of type I and type III roofing asphalt fumes, generated at temperatures similar to actual roofing operation (316 +/- 10 degrees C). The frequencies of micronucleated cells in the treated and control cultures were determined. Additionally, immunofluorescent staining of kinetochore with human anti-kinetochore primary antibody and flouresceinated goat anti-human IgG was used to investigate the potential mechanism of micronucleus formation. The results show that both types of roofing asphalt fume condensates caused a significant increase in the frequency of micronucleated cells, and that 70% of micronucleated cells induced by asphalt fume condensates carried kinetochore-positive micronuclei. These findings indicate that both type I and type III roofing asphalt fumes are capable of causing principally cytogenetic damage by spindle apparatus alterations in cultured mammalian cells.

Animals↗

PubMed1996

Trivalent counterion condensation on DNA measured by pulse gel electrophoresis.

Pulse gel electrophoresis was used to measure the reduction of mobilities of lambda-DNA-Hind III fragments ranging from 23.130 to 2.027 kilobase pairs in Tris borate buffer solutions mixed with either hexammine cobalt(III), or spermidine3+ trivalent counterions that competed with Tris+ and Na+ for binding onto polyion DNA. The normalized titration curves of mobility were well fit by the two-variable counterion condensation theory. The agreement between measured charge fraction neutralized and counterion condensation prediction was good over a relatively wide range of trivalent cation concentrations at several solution conditions (pH, ionic strength). The effect of ionic strength, trivalent cation concentration, counterion structure, and DNA length on the binding were discussed based on the experimental measurements and the counterion condensation theory.

DNA, Viral↗

PubMed1996

A novel method for detecting apoptosis shows that hepatocytes undergo a time dependent increase in DNA cleavage and chromatin condensation which is augmented after TGF-beta 1 treatment.

This study describes a new method for quantitating apoptosis in hepatocyte monolayers in which nuclei were isolated from the cells and DNA strand breaks detected by in situ end-labeling and flow cytometry. Most (97%) nuclei from untreated hepatocytes had low end-labelling and were derived from non-apoptotic cells. Approximately 2-3% of the nuclei had high end-labelling and originated from apoptotic hepatocytes. The numbers of these nuclei increased linearly from 3 to 85% between 0 and 48 h after treatment with transforming growth factor-beta 1 (TGF-beta 1). However, a morphological assessment of apoptosis with Hoechst H33258 showed that the proportion of apoptotic nuclei plateaued at 18-19% between 24 and 48 h after TGF-beta 1 treatment. Thus, the in situ end-labeling technique also detected DNA cleavage in nuclei which did not have an obvious apoptotic morphology. Confocal microscopy of low and high end-labelled nuclei which had been separated by fluorescent cell sorting showed that nuclei with high levels of end-labeling exhibited a wide diversity of morphologies. These included nuclei with little or no chromatin condensation and nuclei with characteristic apoptotic morphology. In addition, nuclei from untreated hepatocytes contained low levels of DNA cleavage, which were localized in areas of condensed chromatin and increased according to the time in culture. Thus, hepatocytes undergo a progressive and cumulative process of DNA cleavage/chromatin condensation which is markedly enhanced by TGF-beta 1.

Animals↗

PubMed2000

Biodistribution, metabolism, and in vivo gene expression of low molecular weight glycopeptide polyethylene glycol peptide DNA co-condensates.

The biodistribution, metabolism, cellular targeting, and gene expression of a nonviral peptide DNA gene delivery system was examined. (125)I-labeled plasmid DNA was condensed with low molecular weight peptide conjugates and dosed i.v. in mice to determine the influence of peptide DNA formulation parameters on specific gene targeting to hepatocytes. Optimal targeting to hepatocytes required the combined use of a triantennary glycopeptide (Tri-CWK(18)) and a polyethylene glycol-peptide (PEG-CWK(18)) to mediate specific recognition by the asialoglycoprotein receptor and to reduce nonspecific uptake by Kupffer cells. Tri-CWK(18)/PEG-CWK(18) DNA co-condensates were stabilized and protected from metabolism by glutaraldehyde crosslinking. An optimized formulation targeted 60% of the dose to the liver with 80% of the liver targeted DNA localized to hepatocytes. Glutaraldehyde crosslinking of DNA condensates reduced the liver elimination rate from a t((1/2)) of 0.8 to 3.6 h. An optimized gene delivery formulation produced detectable levels of human alpha1-antitrypsin in mouse serum which peaked at day 7 compared to no expression using control formulations. The results demonstrate the application of formulation optimization to improve the targeting selectivity and gene expression of a peptide DNA delivery system.

Animals↗

PubMed2000

The greater negative charge density of DNA in tris-borate buffers does not enhance DNA condensation by multivalent cations.

As indicated by recent measurements of the electrophoretic free solution mobility, DNA appears to have a greater helical charge density in Tris-borate-EDTA (TBE) buffers than in Tris-acetate-EDTA (TAE) buffers. Since electrostatic forces play a major role in DNA packaging processes, we have investigated the condensation of closed circular plasmid DNA using total intensity and dynamic light scattering in Tris-borate, Tris-acetate, and Tris-cacodylate buffers with cobaltic hexa-amine (III) [Co(NH(3))(3+)(6)]. We find that neither the critical concentration of Co(NH(3))(3+)(6) nor the hydrodynamic radii of the resulting condensates vary significantly in the buffer systems studied here despite the prediction that DNA condensation should occur at significantly lower Co(NH(3))(3+)(6) concentrations in Tris-borate buffers. Assuming a persistence length behavior similar to B-DNA in the presence of multivalent cations, a decrease in the attractive counterion correlation pressure decay length in Tris-borate buffers does not account for our observations. It is possible that the binding of multivalent cations to DNA may hinder borate association with the DNA double helix.

Amines↗

PubMed2002

Bose-Einstein condensation in a dilute gas: the first 70 years and some recent experiments (Nobel Lecture).

Bose-Einstein condensates of dilute gases offer a rich field to study fundamental quantum-mechanical processes, manipulation of the speed at which light propogates, observation of atomic pair-formation and superfluidity, or even simulating white dwarf stars. Still more radical applications are on the horizon. However, their initial creation was a masterpiece of experimental physics. After an initial process of laser cooling (which itself won its developers the 1997 Nobel Prize), atoms in a magnetic-optical trap must be safely transferred into a purely magnetic trap, where the condensation process begins at 170 nK and 20 nK a pure condensate of 2000 atoms could be created. More astonishingly, Wieman and Cornell showed these low temperatures could be achieved in "bench scale" equipment rather than the massive pieces normally demanded by cryoscience. For their 1995 discovery of this new state of matter, they were awarded the 2001 Nobel Prize in Physics.

Chemistry, Physical↗