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PubMed2002

Effects of exogenous nitric oxide on oral squamous cell carcinoma: an in vitro study.

PURPOSE: Nitric oxide (NO) is a newly found unstable free radical gas, serving as an important mediator, messenger, and signal transduction molecule and involved in a variety of pathophysiologic processes. Recently, NO has been reported to have cytotoxic effects on several tumor cells as an effector molecule of activated macrophage. The objective of this study was to investigate the effects of exogenous NO on oral squamous cell carcinoma cell line and to try to clarify the possible mechanisms by which it kills tumor cells. METHODS: TSCCa cell line, established from a patient with oral squamous cell carcinoma of the tongue, was exposed to various concentrations of exogenous NO that were released from an NO donor, sodium nitroprusside (SNP), for 48 hours. Nitrite/nitrate levels in the culture supernatant were determined with a commercial available NO kit. Both morphologic and ultrastructural changes were evaluated by reverse phase contrast microscopy or transmission electron microscopy. The DNA was harvested from SNP-treated or untreated TSCCa cells and assessed by agarose gel electrophoresis. RESULTS: SNP released NO into medium in a dose-dependent manner. NO had a concentration-dependent cytotoxicity against TSCCa cells. NO induced tumor cell death through apoptosis, which was characterized by incompleteness of nuclear membrane, disappearance of nucleole and nuclear condensation, chromatin margination, or chromatin homogenization. Agarose gel electrophoresis showed a typical internucleosomal DNA cleavage pattern (DNA ladder), a reliable indicator of apoptosis. CONCLUSIONS: Our results suggested that NO had a tumoricidal potential against oral cancer cells. NO might exert its cytotoxicity as an effector molecule of activated microphage through at least apoptosis.

Antineoplastic Agents↗

PubMed1998

Kartagener's syndrome: a re-visit with Chinese perspectives.

The objective of this study was to evaluate the clinical, radiological investigation profiles, and ciliary function and ultrastructure in Chinese patients with Kartagener's syndrome (presence of dextrocardia, sinusitis and bronchiectasis). All patients with dextrocardia were assessed for the presence of sinusitis and bronchiectasis in our hospital network. Patients identified with Kartagener's were assessed when they were at steady state for their bronchiectasis. Seven cases (4 males; mean age 34.9 years) were identified and systematically reviewed. The mean 24 h sputum volume was 26.6 +/- 32.77 mL/day and the patients suffered from a mean of 2.9 exacerbations/year. Nasal symptoms (anosmia in one, obstruction in six and persistent discharge in three patients) were common. Only two cases (1 M) were married and both had normal fertility. Lung function assessment showed a mean FEV1/FVC of 83.3 +/- 38.78/86.5 +/- 36.72 (% predicted) with little reversibility. High resolution computerized tomography (HRCT) revealed bronchiectactic involvement of the lower lobes in seven and middle lobe/lingula in four cases. Assessment of alpha-1-anti-trypsin, aspergillus precipitins, auto-antibodies and serology for Pseudomonas pseudomallei was normal. Sputum culture yielded Pseudomonas aeruginosa in three, Haemophilus influenzae in three and commensals in one case. Phase contrast microscopy assessment of respiratory cilia, obtained by brushing the inferior turbinate, revealed that most of the mucosa was unciliated. The mean ciliary beat frequency was 5.2 +/- 6.76 Hz (range 0-13.7; normal range 12-18 Hz). Four patients had immotile cilia whilst the rest had normal ciliary movement. Transmission electron microscopy showed the absence of dynein arms in four patients. The results of this study show that patients with Kartagener's syndrome may have normal ciliary ultrastructure and the absence of dynein arms is not necessarily associated with ciliary immotility. The presence of ciliary immotility might have prognostic value as these patients appear to have more active bronchiectasis. Our experience on this series should help clinicians in the investigation and management of these patients.

Adolescent↗

PubMed1975

Interaction of water with egg lecithin in benzene solution.

Benzene solutions of purified egg lecithin, with small amounts of water added, have been examined by 60 MGz and 100 MHz NMR spectroscopy, infrared spectrophotometry and phase contrast microscopy. The transverse relaxation times of the water, N-methyl and O--H protons are dependent on water concentration. This dependence changes sharply for the water proton at a level of one water molecule per lecithin monohydrate molecule. These results do not fully agree with those reported by other workers. Four mathematical models are examined which could account for the behaviour of the water protons. Models which assume a constant transverse relaxation time for water protons above a level of one water molecule per lecithin molecule cannot predict the behaviour observed. It is sufficient to assume that water protons above this concentration have a single relaxation time which is a linear function of water concentration. The added water associates primarily with the phosphate in the lecithin head group. Above nine water molecules per lecithin monohydrate molecule free water is present in the system.

Benzene↗

PubMed1996

Radiotherapy as a cisplatin-sensitizer in a resistant ovarian carcinoma cell line.

BACKGROUND: Stage III ovarian carcinoma has shown resistance to adjuvant chemotherapy following surgical cytoreduction. With recurrence of ovarian carcinoma, cell lines may develop resistance to previously used chemotherapy. This contributes to the fact that survival rates for patients with ovarian carcinoma have not been dramatically improved in decades. The objective of this study is to evaluate radiotherapy as a cisplatin-sensitizer in a cisplatin-resistant ovarian carcinoma cell line. METHODS: In vitro OVCAR-3 human ovarian carcinoma cells were irradiated with external beam radiation (XRT) at doses of 500, 1,500, and 4,500 centigray (cGy) in a single fractionation. Twelve hours after XRT, cells were treated with a dose of cisplatin for 2 hours (0, 1, 3, 9, and 90 micrograms/mL). Cell attachment was determined by cell counts using a hemocytometer under phase-contrast microscopy. Analysis of variance followed by the Student Newman Keuls Test were used for statistical analysis. RESULTS: Dose-response curves demonstrate the results of this study as follows: (1) XRT has a significant direct effect on cell attachment of OVCAR-3 cells in a dose-response relationship. (2) cisplatin has no effect on cell attachment in the absence of XRT. (3) When cells are exposed to XRT, cisplatin demonstrates a dose-response effect on cell attachment with a dose of XRT as low as 500 Gy. CONCLUSIONS: This in vitro study suggests that XRT sensitizes cisplatin-resistant OVCAR-3 to cisplatin. This occurred with doses of radiation low enough to suggest a potential clinical role in treating resistant ovarian carcinoma.

Analysis of Variance↗

PubMed1981

Identification of beta-adrenergic receptor binding sites in rat brain microvessels, using [125I]iodohydroxybenzylpindolol.

Brain microvessels were prepared from rat cerebral cortex. The purity was confirmed by phase-contrast microscopy and by the measurement of an enzymatic marker, gamma-glutamyltranspeptidase. The microvessel preparation was subjected to radioreceptor assay using a 125I-labelled beta-adrenergic antagonist, hydroxybenzylpindolol (IHYP). The binding was linear with protein concentration up to at least 80% microgram per tube. It was saturated at 200 pM IHYP concentration. The KD value calculated by Scatchard analysis was 69.4 +/- 9.9 pM. The maximum binding (Bmax) was 107 +/- 4 fmol/mg protein. The binding reached equilibrium within 30 min and was dissociated by addition of (-)-propranolol. The inhibitory effects of isomers of propranolol and isoproterenol on this binding showed that (-)-isomers were two orders of magnitude more potent than the (+)-isomers. Other neurotransmitters did not affect IHYP binding. The characteristics of the binding, saturability, high affinity, reversibility and stereospecificity, suggest tha IHYP is bound to beta-adrenergic receptor sites located on brain microvessels.

Animals↗

PubMed1980

Direct studies of dikaryotization in Schizophyllum commune. I. Live inter-cellular nuclear migration patterns.

Compatible matings of Schizophyllum commune were performed on glucose-peptone-yeast extract medium appended with gelatin (18%) and studied by phase contrast microscopy during nuclear migration. Three categories of nuclear migration were observed. Type I involved a pulsatile jerking of the entire cytoplasmic contents of the hypha, changed direction periodically, and, during periods of cytoplasmic tranquility, the nucleus continued to migrate. Type II A migration of nuclei occurred in the absence of visible cytoplasmic flow. Both Type I and Type II A nuclear movements exceeded the hyphal growth rate by 10--20-fold. Type II B nuclear migration also occurred in the absence of visible cytoplasmic flow and the velocity was within the range of the hyphal growth rate. No specific organelles that were detected either directed or facilitated Type II A or Type II B nuclear movements. The nucleolus could either lead or trail relative to the direction of nuclear movement. Nuclear migration can be attributed to both cytoplasmic flow and self motility, depending upon the particular regions of the migration hypha in which it occurs.

Agaricales↗

PubMed1987

Chemically unrelated tumor promoters induce identical morphological changes in cultured rat oral epithelium.

By use of phase contrast microscopy, transmission and scanning electron microscopy the cytomorphological effects of different known tumor promoters (TPA, teleocidin, mezerein and anthralin) were studied and compared to the cytomorphological effects of a variety of non- or weak promoting irritants (ethylphenylpropiolate (EPP), phorbol, acetone, ethanol and dimethyl sulfoxide (DMSO]. The studies were conducted in cultures of stratifying rat tongue epithelial cells. It was demonstrated that the tumor promoters induce characteristic cytomorphological alterations, the most striking changes being elongation of the cells and formation of long cytoplasmic extensions together with induction of so-called "dark cells". The non-promoting irritants exerted well-known cytotoxic reactions like cell rounding and cell sloughing. It is suggested that the characteristic tumor promotor induced cytomorphological effects partly reflects a block of the intercellular communication and thus should be paid more attention as an important characteristic event among the pleiotropic effects exerted by tumor promoters.

Animals↗

PubMed2006

Challenges in cryopreservation of clouded leopard (Neofelis nebulosa) spermatozoa.

The clouded leopard (Neofelis nebulosa) is an endangered species that is difficult to breed in captivity. Species management could benefit from the use of artificial insemination (AI) with frozen-thawed spermatozoa, but there have been no detailed studies of sperm cryosensitivity. The purposes of this study were to: (1) re-characterize seminal characteristics in the clouded leopard 20 years after the first descriptive studies Wildt et al., [Wildt DE, Howard JG, Hall LL, Bush M. Reproductive physiology of the clouded leopard. I. Electroejaculates contain high proportions of pleiomorphic spermatozoa throughout the year. Biol Reprod 1986; 34: 937-947]; and (2) conduct a comparative cryopreservation study on the feasibility of sperm from this species surviving a freeze-thawing stress. Ejaculates were collected from five adult males and subjected to standard analysis, followed by a two-step straw freezing protocol that evaluated the impact of thawing, dilution, centrifugation and in vitro culture (through 4 h) on sperm motility and acrosomal integrity. Additionally, we assessed the impact of both a traditional permeating cryoprotectant (glycerol at a final dilution of 4%) and an unconventional nonpermeating trisaccharide; raffinose (R) at a final dilution of 4% or 8%, with or without 4% glycerol on sperm cryosurvival. The clouded leopard produced an extremely poor quality ejaculate; although approximately 70% of fresh sperm were motile, >80% were malformed. Phase contrast microscopy revealed that 40% of all sperm had abnormal acrosomes, but Coomassie blue staining indicated that acrosomal abnormalities existed in almost 70% of spermatozoa. Upon freeze-thawing, sperm motility declined markedly (P < 0.05) by an average of 40%, regardless of diluent used. Interestingly, raffinose was as effective as glycerol in protecting both sperm motility and acrosomal integrity. Although no acrosomal damage was seen immediately after thawing, < 6% morphologically normal intact acrosomes were present by the last measured time point. In conclusion, the clouded leopard is a rare felid that (at least in North American zoos) is producing extraordinarily poor quality ejaculates. There are so many sperm with unexplained deranged acrosomes that it will be particularly challenging to use traditional AI with thawed sperm as an adjunct management tool.

Animals↗

PubMed2004

T lymphocyte mediated lysis of mitomycin C treated Tenon's capsule fibroblasts.

AIMS: To evaluate the effect of T cell co-culture on mitomycin C treated and untreated Tenon's capsule fibroblasts. METHODS: IL-2 dependent allogeneic T cells were incubated over a monolayer of mitomycin C treated or control fibroblasts. Fibroblast numbers were evaluated by direct counts using phase contrast microscopy. To determine whether T cell mediated lysis was a consequence of MHC mismatch, co-culture experiments were repeated with autologous T cells. The effect of Fas receptor blockade was established by co-incubation with a Fas blocking (M3) antibody. RESULTS: T cell co-culture resulted in a dramatic reduction in fibroblast survival compared to mitomycin C treatment alone (p = 0.032). T cell killing required fibroblast/lymphocyte cell to cell contact and was observed in both allogeneic and autologous co-culture experiments. Fas blocking antibodies did not significantly inhibit T cell killing (p = 0.39). CONCLUSION: T cells augment mitomycin C treated fibroblast death in vitro. Similar mechanisms may contribute to the cytotoxic effect of mitomycin C in vivo and account for the largely hypocellular drainage blebs that are observed clinically.

Antibiotics, Antineoplastic↗

PubMed2003

In vitro study on the closure of posterior capsulorrhexis in the human eye.

PURPOSE: An unexplained clinical observation is the development of posterior capsular opacification (PCO), even when the central part of the posterior capsule has been removed. The purpose of this study was to investigate in vitro the mechanisms involved in the closure of the posterior capsulorrhexis in a capsular bag model. METHODS: A sham extracapsular cataract extraction was performed in 71 human donor eyes, followed by a central posterior capsulorrhexis 3 to 4 mm in diameter. Each capsular bag was pinned to a PMMA ring with a central hole of 5 mm and placed in a Petri dish. The capsular bags were cultured and monitored for 3 to 7 weeks by phase-contrast microscopy, after which they were prepared for light, transmission, and scanning electron microscopy. RESULTS: Proliferation of lens epithelial cells (LECs) within the posterior rhexis area was found in 22 cases (31%) of which 3 had a complete closure. In the absence of the posterior capsule, a monolayer of LECs was observed growing on a basal lamina, consisting of loosely arranged fibers. Further observations on noncultured capsular bags revealed that this basal lamina corresponds to the anterior hyaloid membrane. CONCLUSIONS: This study corroborates the clinical observation that LECs that remain after cataract extraction have the potential to proliferate, in the absence of their natural substrate, on a basal lamina of vitreous origin and are able to close the posterior capsulorrhexis partially or totally in approximately one third of cases.

Adolescent↗

PubMed1990

In vitro toxicity of gentamicin to corneal epithelial cells.

We report morphologic and viability changes in the rabbit corneal epithelium exposed in vitro to gentamicin sulfate. Rabbit corneal epithelial cells (3 x 10(5)) were seeded in replicate 24-well plates at their first in vitro passage, and gentamicin in concentrations of 0, 50, 250, 500, 1,000, or 5,000 micrograms/ml was added to the tissue culture medium beginning 7 days after subculture. By phase contrast microscopy, changes in cell morphologic appearance, particularly increased cytoplasmic granularity, were observed in the 5,000-micrograms/ml groups as early as 24 h after introduction of the drug. At 48 h, similar findings were observed in the 250-micrograms/ml group and at all higher concentrations. The cytoplasmic granularity was not noted in the 0- or 50-micrograms/ml groups. By electron microscopy, these observations correlated with ultrastructural findings of increased accumulations of intralysosomal bodies beginning in the 250-micrograms/ml group after 48 h of exposure to gentamicin. Furthermore, a statistically significant difference (p = 0.001) was demonstrated between the total number of viable cells in the low-dose group (50-micrograms/ml) and the high-dose groups (greater than or equal to 250-micrograms/ml) for exposure periods of 48 h or more. These findings demonstrate aminoglycoside toxicity to corneal epithelial cells in vitro similar to that seen in the human kidney and conjunctiva.

Animals↗

PubMed1988

Formation of flagella during interphase in secondary spermatocytes from Xenopus laevis in vitro.

In cell culture, single motile flagella, 1 micron in length, were observed to grow from secondary spermatocytes of Xenopus laevis within 2-3 hours after telophase I, at 22 degrees C. About 90% of the secondary spermatocytes formed flagella as observed by phase-contrast microscopy. The flagella grew up to 2-6 microns in length during interphase II, which lasted about 18 hours. The presence of the "9 + 2" microtubular structure of the flagellar axonemes of secondary spermatocytes was confirmed by electron microscopy. When chromosomal condensation began (prophase II), the flagella were resorbed into the cells and, after the second meiotic division, a flagellum was formed again by each of the round spermatids. Thus, there appears to be a close relationship between the meiotic division cycle and the formation of flagella. The possible contribution of Sertoli cells to the formation of flagella in secondary spermatocytes was examined by reducing the number of Sertoli cells to less than ten per culture. Under these conditions, flagella formed in secondary spermatocytes with very high efficiency. It is very likely that secondary spermatocytes form flagella in vivo, since the secondary spermatocytes were observed to have flagella immediately after dissociation of the testes.

Animals↗

PubMed2005

Anti-endothelial cell antibodies from lupus patients bind to apoptotic endothelial cells promoting macrophage phagocytosis but do not induce apoptosis.

OBJECTIVE: Anti-endothelial cell antibodies (AECA) have been reported to induce apoptosis. We investigated the induction of apoptosis by these autoantibodies and their involvement in the removal of apoptotic cells. METHODS: AECA isolated from patients with active systemic lupus erythematosus (SLE) were incubated with human umbilical vein endothelial cells (HUVECs). AECA-positive sera were identified using a cell-based ELISA. Apoptosis was measured by morphology and phosphatidylserine externalization using flow cytometry with fluorescein isothiocyanate (FITC)-conjugated annexin V. Flow cytometry was used to investigate AECA binding to apoptotic cells using FITC-conjugated anti-human immunoglobulin G (IgG). Apoptotic endothelial cells were stained with a red dye (PKH26) and co-cultured with macrophages, and phagocytosis was visualized under phase contrast microscopy. RESULTS: AECA from patients with SLE did not induce apoptosis compared with normal IgG (nIgG) at any time point, as assessed by morphology (at 24 h, P = 0.167) or phosphatidylserine externalization (at 24 h, P = 0.098). However, there was increased binding of AECA to apoptotic endothelial cells (48.8 +/- 11.9 compared with 25.8 +/- 6.7% AECA binding to freshly isolated cells, P< 0.001). These opsonized endothelial cells showed greater phagocytosis by macrophages (mean phagocytic index 24.9 +/- 4.5%) when cells opsonized with nIgG were compared with AECA (34.8 +/- 3.4% n = 5, P = 0.01). CONCLUSION: In conclusion, AECA bind to apoptotic endothelial cells but do not induce endothelial cell apoptosis. Macrophage phagocytosis is increased by opsonization of apoptotic endothelial cells by AECA, a proinflammatory mechanism of cell removal.

Adolescent↗

PubMed1996

Does the HMG-CoA reductase inhibitor pravastatin influence nucleation of cholesterol crystals in supersaturated model bile?

OBJECTIVE: To assess whether the presence in bile of HMG-CoA reductase inhibitors, which are secreted predominantly into the bile, influences biliary lithogenicity. DESIGN: Physiologic biliary concentrations of the hydrophilic HMG-CoA reductase inhibitor pravastatin were added to supersaturated model bile (cholesterol saturation index 1.4) and vesicles, the latter with and without the concomitant addition of the nucleation-promoting bile salt taurodeoxycholate. OUTCOME MEASURES: Nucleation time, defined as the number of days after which cholesterol monohydrate crystals are visible by phase contrast microscopy in filtered samples of model bile and vesicles, was assessed. RESULTS: The addition of pravastatin 0.01-1 mg/ml did not influence the nucleation time of supersaturated model bile (mean nucleation time without pravastatin: 8.3 +/- 2.2 days (SD), with pravastatin 1 mg/ml 9.3 +/- 0.4 days and pravastatin 0.01 mg/ml 7.6 +/- 2.3 days). The addition of similar concentrations of pravastatin to vesicle fractions alone did not influence nucleation time (> 20 days), nor could it prevent the nucleation-promoting effect of taurodeoxycholate (nucleation time with or without pravastatin 1 day). CONCLUSION: The results from this in-vitro study indicate that the presence of pravastatin in bile may not influence gallbladder bile lithogenicity. It can be hypothesized that this also applies to other HMG-CoA reductase inhibitors.

Anticholesteremic Agents↗

PubMedDate not supplied

Effect of heparin-reduced glutathione on hamster sperm DNA unpacking and nuclear swelling.

This study examined the kinetics of sperm nuclear decondensation induced by the action of physiological concentrations of heparin and glutathione in hamster sperm nuclei as a chromatin model that contains protamine P1 and P2. Sperm suspension was incubated at different temperatures (37, 40, 43, and 46 degrees C) in media, keeping constant the concentration of either heparin or GSH and increasing concentrations of the other reagent. Spermatozoa nuclei without any treatment, incubated for 72 h, appear densely condensed. Swelling of hamster spermatozoa nuclei was observed after 30 min of incubation in the presence of efficient concentrations of heparin-GSH. The extent of this time lag was significantly reduced at higher temperatures. DNA presence was verified by the use of ethidium bromide, acridine orange, and Feulgen stain. Phase-contrast microscopy shows that nuclear decondensation begins at the equatorial levels, with DNA highly condensed at the acrosome pole, and the basal pole as the DNA attachment point. Electron microscopy observations showed that hamster sperm nuclei initiates its decompaction at the peripheral regions and this behavior remains until late stages of decondensation, nevertheless, the chromatin is organized into "hub-like" nuclear bodies that measured 10-100 nm in diameter, joined by a network of chromatin fibers with apparent reduction in number. At the decondensation full stage, the network seems to be wide open with a reduced number of hub-like nuclear bodies present in the interlace. DNA is not organized into topologically constrained loop domains and is attached to the basal plate instead of to the nuclear matrix or any other structure.

Animals↗

PubMed1995

Microbiological features of gingivitis in pubertal children.

The subgingival microflora of 42 pubertal children (aged 12-15 years) and 18 young adults (aged 21-25 years) was investigated by anaerobic culture and phase contrast microscopy. Motile rods, spirochetes and Prevotella intermedia were elevated proportionately in pubertal children with gingivitis (median GI > or = 1); however, no statistically significant differences in enumerated organisms on selective media were observed between pubertal children and young adults. These organisms were positively correlated with the index of bleeding on probing and the gingival index of pubertal children. Pubertal children were divided into 3 distinct subject clusters according to the similarity of subgingival microbial features, and the subjects who were then selected for the gingivitis group were distributed into clusters 1 and 2. The proportions of motile rods, P. intermedia and Eikenella corrodens were significantly higher in cluster 2 than in cluster 1. These results suggest that these 2 species and motile rods which differentiated features of clusters, are useful for screening of high-risk subjects for worsening of inflammation.

Actinomyces↗

PubMed1988

[Exact description of non-glomerular and glomerular erythrocyte forms in pediatric hematuria].

We examined 70 urinary sediments of 35 children with non-glomerular hematuria (NGH) and 65 urinary sediments of 17 children with glomerular hematuria (GH) by phase-contrast microscopy at 1,000 X magnification. In each urinary sediment 200 erythrocytes were classified into 18 types of "non-glomerular erythrocytes" and 15 types of "glomerular erythrocytes". According to the percentage of greatly altered erythrocytes the urinary finding was termed isomorphic, mixed or dysmorphic. In 91% of the urinary sediments of patients with NGH the erythrocyte pattern was isomorphic, and in 91% of the urinary sediments of children with GH it was dysmorphic. 9 types of non-glomerular erythrocytes and 10 types of glomerular erythrocytes constituted 94.5% of all 26,809 erythrocytes examined. Torocytes (doughnut-like cells) can be considered characteristic for GH. This study demonstrates a high specificity of this method in discriminating NGH from GH. The exact morphological description of urinary erythrocytes allows the method to be reproducible. For future use examiners can concentrate on the 19 commonest erythrocyte types.

Adolescent↗

PubMed1988

Cytoprotective effect of acetaminophen against taurocholate-induced damage to rat gastric monolayer cultures.

Acetaminophen has recently been reported to protect against drug damage to gastric mucosa in vivo. The present study tested acetaminophen protection in cultured rat gastric mucous cells against sodium taurocholate-induced damage and assessed the role of endogenous prostaglandins. Cell damage was assessed by phase-contrast microscopy and quantitated by Chromium-51 release assay which positively correlated with the trypan blue dye exclusion test (r = 0.98). The effect of acetaminophen on the production of PGE2 and 6-keto-prostaglandin F1a (6KF) was also studied. Sodium taurocholate caused cell death in a dose-dependent manner as indicated by increased 51Cr release. Preincubation with 5 mM acetaminophen significantly reduced 51Cr release caused by 5 mM sodium taurocholate, producing a 40% increase in cell survival. This cytoprotection was not blocked by indomethacin. PGE2 and 6KF of the media did not change after preincubation with nondamaging concentrations of acetaminophen or taurocholate. These results indicate that: (1) acetaminophen exerts a direct protective effect on gastric mucous cells cultured in vitro independent of indirect factors such as blood flow and (2) this protection is not associated with increased prostaglandin production.

6-Ketoprostaglandin F1 alpha↗