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Biomedical subjects

M J Rossi

Publications and source records attributed to M J Rossi.

17 recordsLinked to original sources
PubMed2006

Uptake of CO2, SO2, HNO3 and HCl on calcite (CaCO3) at 300 K: mechanism and the role of adsorbed water.

All experimental observations of the uptake of the four title compounds on calcite are consistent with the presence of a reactive bifunctional surface intermediate Ca(OH)(HCO3) that has been proposed in the literature. The uptake of CO2 and SO2 occurs on specific adsorption sites of crystalline CaCO3(s) rather than by dissolution in adsorbed water, H2O(ads). SO2 primarily interacts with the bicarbonate moiety whereas CO2, HNO3 and HCl all react first with the hydroxyl group of the surface intermediate. Subsequently, the latter two react with the bicarbonate group to presumably form Ca(NO3)2 and CaCl2.2H2O. The effective equilibrium constant of the interaction of CO2 with calcite in the presence of H2O(ads) is kappa = deltaCO2/(H2O(ads)[CO2]) = 1.62 x 10(3) bar(-1), where CO2 is the quantity of CO2 adsorbed on CaCO3. The reaction mechanism involves a weakly bound precursor species that is reversibly adsorbed and undergoes rate-controlling concurrent reactions with both functionalities of the surface intermediate. The initial uptake coefficients gamma0 on calcite powder depend on the abundance of H2O(ads) under the present experimental conditions and are on the order of 10(-4) for CO2 and 0.1 for SO2, HNO3 and HCl, with gamma(ss) being significantly smaller than gamma0 for HNO3 and HCl, thus indicating partial saturation of the uptake. At 33% relative humidity and 300 K there are 3.5 layers of H2O adsorbed on calcite that reduce to a fraction of a monolayer of weakly and strongly bound water upon pumping and/or heating.

Journal Article↗
PubMed2005

The heterogeneous interaction of HOCl with solid KBr substrates: the catalytic role of adsorbed halogens.

The heterogeneous reactivity of HOCl on solid KBr at ambient temperature has been studied using a Knudsen flow reactor. On solid KBr steady-state uptake experiments reveal the formation of Br- and Cl-containing reaction products formed in secondary reactions such as Br(2), BrCl, HOBr, BrOCl, Cl(2) and Cl(2)O with the latter two predominating in the late stages of the reaction. The uptake coefficient gamma spanning a range between 0.15 and 1 x 10(-3) and product yields of HOCl strongly depend on the nature of the solid sample, whether grain, ground grain or thin sprayed film, as well as on sample processing such as pumping and/or heating. Furthermore, the presence of adsorbed halogen species such as Br(2)(a) are crucial for the kinetics of the reaction of HOCl with solid KBr substrates. The presence of surface-adsorbed water (SAW) leads to deactivation of KBr whereas mechanical stress such as grinding leads to the formation of surface defects that become reaction centers. Desorption of SAW at T > 620 K induces high reactivity of the KBr sample at ambient temperature. A reaction mechanism encompassing all significant observations including unusual autocatalytic activity is given as there is no direct reaction of HOCl with solid KBr. It stresses the importance of adsorbed Br-containing species such as Br(2)(a) and HBr(a) that initiate the heterogeneous chemistry of HOCl on solid KBr in the presence of SAW. The role of surface acidity and SAW for the extent of reaction is emphasized.

Adsorption↗
PubMed2002

Inoculum production of the ectomycorrhizal fungus Pisolithus microcarpus in an airlift bioreactor.

Many important tree species in reforestation programs are dependent on ectomycorrhizal symbiosis in order to survive and grow, mainly in poor soils. The exploitation of this symbiosis to increase plant productivity demands the establishment of inoculum production methods. This study aims to propose an inoculum production method of the ectomycorrhizal fungus Pisolithus microcarpus (isolate UFSC-Pt116) using liquid fermentation in an airlift bioreactor with external circulation. The fungus grew as dark dense pellets during a batch fermentation at 25.5 degrees C and air inlet of 0.26-0.43 vvm. The maximum biomass (dry weight) achieved in the airlift bioreactor was approximately 5 g.l(-1) after 10-11 days. The specific growth rate (micro(x)) in the exponential phase was 0.576 day(-1), the yield factor (Y(X/S)) 0.418, and the productivity (P(X)) 0.480 g.l(-1).day(-1). This specific growth rate was higher than that observed by other authors during fermentation processes with other Pisolithus isolates. The method seems to be very suitable for biomass production of this fungus. However, new studies on the fungus growth morphology in this system, as well as on the efficiency of the process for the cultivation of other ectomycorrhizal fungi, are necessary. It is also necessary to test the infectivity and efficiency of the inoculum towards the hosts.

Biomass↗
PubMed1998

Prostaglandin f2alpha treatment in vivo, but not in vitro, stimulates protein kinase C-activated superoxide production by nonsteroidogenic cells of the rat corpus luteum.

Luteal regression is associated with the generation of reactive oxygen species (ROS). To determine the nature of the ROS generator, cells isolated from luteinized rat ovaries were examined for ROS production using luminol-amplified chemiluminescence (LCL). Cells cultured for 2-48 h exhibited minimal LCL, but there was a significant (30- to 50-fold), rapid (maximum at 3-5 min), and dose-dependent increase in LCL in response to phorbol ester (phorbol 12-myristate 13-acetate; TPA; ED50 = 0.03 microM) and diacylglycerol (1,2-dioctanoyl-glycerol; ED50 = 30 microM). The TPA-induced response was cell number dependent and was virtually abolished by superoxide dismutase, freezing, or heating (95 degrees C for 5 min). Zymosan, known to induce a phagocytic response in leukocytes, stimulated a superoxide (O2-.) response with a slow onset (maximum at 40 to 60 min) and a maximum about one third of that observed for TPA. The response to TPA and zymosan was inhibited by the NADPH/NADH-oxidase inhibitor, diphenylene iodonium (ID50 = 5 microM for TPA), but not by the mitochondrial inhibitors, potassium cyanide, rotenone, or sodium azide. Fractionation of cells by centrifugal elutriation showed that TPA-stimulated O2-. production coeluted with the nonsteroidogenic cells and that little, if any, O2-. generation coeluted with the steroidogenic cells. Cells isolated 1, 2, and 4 h after in vivo treatment with a luteolytic dose of prostaglandin F2alpha (PGF2alpha) showed a significant increase in TPA-stimulated O2-. production at 2 h, whereas luteal cells or corpora lutea incubated directly with 1 microM PGF2alpha did not show any increase in response. Corpora lutea isolated from naturally regressed ovaries (18 days after ovulation) showed a significantly elevated level of TPA-stimulated O2-. production. In conclusion, there is a superoxide generator in luteinized ovaries that is activated through a protein kinase C pathway, localized in nonsteroidogenic cells, transiently increased during PGF2alpha-induced luteolysis in vivo, and elevated during natural luteal regression.

Animals↗
PubMed1994

The effect of surgical glove powder on proliferation of human skin fibroblast and monocyte/macrophage.

The effect of surgical glove powders (Biosorb, Keoflo, and CaCO3) and Hydrocote (powder-free lubricating agent, Biogel) was examined on human skin fibroblasts and monocyte/macrophage cell lines (U937 and HL-60). Glove powders (0.1-100 micrograms/ml) in the presence of 10% fetal bovine serum (FBS) had no significant effect on the rate of 3H-thymidine uptake and proliferation of these cells after 48 h and 7 days of exposure, respectively. However, they inhibited HL-60 growth after 10 days, and Biosorb and CaCO3 inhibited U937 after 10-21 days of exposure compared with control. In the presence of low serum (0.5%), Biosorb, but not Keoflo, CaCO3, and Hydrocote, inhibited HL-60 cells after the third day of exposure (p < 0.05), whereas they were without any effect on U937 cells. Further incubation resulted in a significant decrease in cell density in all treatments, as well as controls, because of cell death. In the presence of 2% serum, glove powder-treated HL-60 significantly increased in cell numbers during the first 3 days, and the cells became stationary thereafter, whereas Keoflo and CaCO3-stimulated U937 reached a maximal by 9 days of treatment. Coculturing of fibroblasts directly with macrophages (0.4-5 x 10(5) cells per dish) or incubation with macrophage culture-conditioned media (CCM) stimulated quiescent fibroblast growth equal to that induced by 10% and 0.5% serum, respectively (p < 0.05). However, incubation of fibroblasts with glove powder-treated HL-60 CCM (except CaCO3) inhibited (p < 0.05) and CCM from Biosorb-treated U937 stimulated (p < 0.05) fibroblast proliferation. The CCM from glove powder-treated HL-60 and U937 did not have any significant effect on the rate of 3H-thymidine incorporation into fibroblasts compared with controls. The present observations suggest that glove powder action on fibroblast and macrophage growth in vitro depends on both the serum concentration of the culture medium and the length of exposure. The results imply that glove powders may have an adverse effect in vivo by directly influencing the biologic activity of macrophages, as well as other cell types, leading to alterations in the early phases of wound healing.

Calcium Carbonate↗
PubMed1994

Insulin-like growth factor I (IGF-I), IGF-I receptors, and IGF binding proteins 1-4 in human uterine tissue: tissue localization and IGF-I action in endometrial stromal and myometrial smooth muscle cells in vitro.

The objective of the present study was to elucidate the presence and cellular distribution of insulin-like growth factor I (IGF-I), IGF-I receptor (IGF-IR), and IGF binding proteins (IGFBPs) in human uterine tissue at various reproductive stages, and to determine the effect of IGF-I and its interaction with epidermal growth factor (EGF) and platelet-derived growth factor (PDGF) in endometrial stromal and myometrial smooth muscle cells in primary culture. Using specific antibodies, immunohistochemical observations indicated that luminal and glandular epithelial cells were the major sites of immunoreactive IGF-I, IGF-IR, and IGFBPs 1-4, followed by myometrial smooth muscle and endometrial stromal cells. The immunostaining intensity of IGF-I, IGF-IR, and IGFBPs in endometrial but not myometrial tissue was cycle-dependent and higher in the late proliferative and early/mid-secretory periods than in the late secretory and postmenopausal periods, with little immunostaining at the early proliferative phase of the menstrual cycle. Stromal and smooth cells in primary cell culture also contained immunoreactive IGF-I, IGF-IR, and IGFBPs. IGF-I at 10-100 ng/ml stimulated 3H-thymidine incorporation in quiescent stromal and smooth muscle cells with maximal effect at 100 ng/ml (p < 0.05). However, in the presence of 2% serum, which induces half-maximal stimulation, IGF-I (100 ng/ml) further increased the rate of 3H-thymidine incorporation in stromal but not smooth muscle cells (p < 0.05). The effect of IGF-I was significantly lower than that induced by EGF (10 ng/ml), PDGF-BB (10 ng/ml) and their combination (p < 0.005), and higher in stromal cells from proliferative, than secretory phase of the cycle in the presence of 2% fetal bovine serum, but not serum-free condition (p < 0.005). The effect of IGF-I on myometrial smooth muscle cells was significantly higher than that induced by EGF, but lower than that induced by PDGF-BB or by EGF+PDGF-BB, without the cycle specificity seen with stromal cells. EGF, PDGF-BB, and their combination with IGF-I, but not IGF-I alone, stimulated stromal and smooth muscle cell growth as determined by a cell proliferation assay. The results indicate that human uterine tissue at various reproductive stages contains immunoreactive IGF-I, IGF-IR, and IGFBPs 1-4. Although IGF-I alone was found to be a weak mitogenic factor for stromal and smooth muscle cells, by interacting with EGF and PDGF-BB in a cycle-dependent manner it may regulate the growth and differentiation of these and other uterine cell types.

Adult↗
PubMed1994

Expression of transforming growth factor-beta (TGF beta) isoforms and TGF beta type II receptor messenger ribonucleic acid and protein, and the effect of TGF beta s on endometrial stromal cell growth and protein degradation in vitro.

Reverse transcription-polymerase chain reaction analysis of total RNA and immunocytochemical observations revealed that human endometrial glandular epithelial and stromal cells in primary culture express messenger RNAs and proteins for transforming growth factor-beta 1 (TGF beta 1), TGF beta 2, and TGF beta 3 as well as TGF beta type II receptor. The epithelial and stromal cells synthesize and secrete into their culture-conditioned medium 2.6 +/- 0.3 and 1.4 +/- 0.2 ng TGF beta 1/10(6) cells, respectively; after transient acidification of the medium, the TGF beta 1 levels were 18.1 +/- 0.4 and 7.8 +/- 0.7 ng/10(6) cells. These cells also contain specific binding sites for [125I]TGF beta 1, indicated by light microscope autoradiography. TGF beta s at 0.01-10 ng/ml neither stimulated or inhibited subconfluent quiescent stromal cells under serum-free condition nor altered the mitogenic action of 10% fetal bovine serum. However, in the presence of 2% fetal bovine serum, which induced half-maximal stimulation of [3H]thymidine incorporation, TGF beta 1 and TGF beta 2 at 0.1-0.5 ng/ml and TGF beta 3 at 0.1-2.5 ng/ml significantly stimulated the rate of [3H]thymidine incorporation into quiescent stromal cells (P < 0.005); they were ineffective at higher concentrations. TGF beta s did not have any effect on cell proliferation, as determined by cell counting; however, at 0.1 ng/ml and higher concentrations, TGF beta s significantly reduced the metabolic activity of stromal cells, as determined by colorimetric 3-(4,5-dimethylthiazol-2-yl)2, 5-diphenyltetrazolium bromide assay (P < 0.05). The stimulatory and inhibitory actions of TGF beta s in both assays were reversible using 5-10 micrograms/ml TGF beta 1- and TGF beta 2- and 3-6 micrograms/ml TGF beta 3-specific neutralizing antibodies. TGF beta 1 at 1 ng/ml had no significant effect on long-lived protein degradation, assayed by incorporation of [14C]valine into newly synthesized protein by stromal cells, and was similar to the effect of epidermal growth factor or platelet-derived growth factor-BB (10 ng/ml). The data suggest that the TGF beta expression by various endometrial cell types in an autocrine/paracrine manner acts as a negative regulator essential for restraining endometrial growth and transition from proliferation to differentiation stages during the secretory phase after mitogenic stimulation during the proliferative phase of the menstrual cycle.

Adult↗
PubMed1993

Cellular distribution of epidermal growth factor, transforming growth factor-alpha, and epidermal growth factor receptor in fascia and peritoneum during healing in the rat: an autoradiographic and immunohistochemical study.

The presence and cellular distribution of epidermal growth factor (EGF), TGF-alpha, and EGF-R were determined in the rat fascial and peritoneal tissue during healing of an incisional injury by means of immunohistochemistry and autoradiographic techniques. The immunostaining intensity for EGF in the regenerating wound area was substantially higher during the first 14 days, then decreased to near prewound levels during 14 to 35 days after surgery. Within the wound area, the most intense immunostaining occurred with inflammatory cells, followed by fascial striated muscle and arterioles, whereas fibroblasts in the regenerating area contained very low immunostaining intensity. The immunostaining pattern for TGF-alpha with the use of three separate polyclonal antibodies that were directed against the amino and carboxy termini of TGF-alpha precursor and a fragment of the mature 50-amino-acid form of TGF-alpha was similar to that seen with EGF and persisted until 28 days after injury. However, fibroblasts in the regenerating area immunostained intensely for TGF-alpha but not for EGF. Quantitative autoradiography of iodine 125-labeled EGF binding and immunohistochemical studies of the EGF-R with monoclonal antibodies that were directed against the extracellular binding domain of EGF-R demonstrated the presence of specific EGF-R in regenerating fascial and peritoneal tissue. Net grain density (100 microm(2)), representing specific binding of (125)I-EGF, was calculated for different cell types in the wound. The grain density over fascial striated muscle, migratory fibroblasts and peritoneal fibroblasts increased by two and one half, three, and four times, respectively, at 7 days and decreased to the values in adjacent unwounded tissue by 21 days after injury (p < 0.05). Immunostaining for the EGF-R generated similar patterns, which persisted for 14 days after injury. The grain density and immunostaining for EGF-R over the arterioles in the wound did not change during the course of healing and was similar to that of the uninjured regions. In summary, these observations indicate that the local levels of EGF, TGF-alpha, and EGF-R increase during the early phases of healing in fascial and peritoneal injury, which suggests a role for these growth factors in the normal mechanism of fascial/peritoneal wound healing and fibrous adhesion formation.

Journal Article↗
PubMed1992

Five-minute treatments with fluorouracil, floxuridine, and mitomycin have long-term effects on human Tenon's capsule fibroblasts.

Proliferating human Tenon's capsule fibroblasts were exposed for 5 minutes to a wide range of concentrations of fluorouracil, floxuridine, and mitomycin. High concentrations of all three agents had prolonged effects on cell proliferation and morphologic characteristics compared with untreated control cells up to 36 days. The highest concentrations of both floxuridine (15,000 micrograms/mL) and mitomycin (1000 micrograms/mL) had an apparent cidal effect, reducing cell numbers below initial cell density. In contrast, although the highest concentration of fluorouracil (25,000 micrograms/mL) inhibited cell proliferation by more than 50% relative to the untreated control cells at 36 days, the cell numbers still increased fourfold compared with the initial cell density. These results demonstrate that 5-minute treatments with high concentrations of these drugs have prolonged effects on the proliferation of human Tenon's capsule fibroblasts in vitro. Single-dose regimens using high concentrations of these drugs at the time of operation may achieve results similar to those of protocols that involve repeated applications.

Cell Division↗
PubMed1992

Presence of epidermal growth factor, platelet-derived growth factor, and their receptors in human myometrial tissue and smooth muscle cells: their action in smooth muscle cells in vitro.

Immunohistochemical observations indicate that human myometrial smooth muscle cells express epidermal growth factor (EGF) and platelet-derived growth factor (PDGF)-AB and contain EGF and PDGF-beta receptors with no variation in intensity with phases of the menstrual cycle. Furthermore, immunofluorescent microscopic studies revealed that primary myometrial smooth muscle cell cultures also express EGF, PDGF-AB, and contain EGF and PDGF-beta, but not alpha-receptor. Incubation of subconfluent smooth muscle cells in serum-free medium leads to quiescence within 48 h as demonstrated by 3H-thymidine incorporation and labeling index. Exposure of quiescent cells to 10% fetal bovine serum stimulates resumption of DNA synthesis and proliferation in a time-dependent manner with a doubling time of 41.6 h. EGF (1.5-50 ng/ml) and PDGF-AB (1-10 ng/ml) in a dose- and time-dependent manner significantly stimulated 3H-thymidine incorporation by quiescent myometrial smooth muscle cells (P less than 0.05). Combinations of EGF (15 ng/ml) and PDGF-AB (10 ng/ml) significantly increased 3H-thymidine incorporation induced by either growth factor alone (P less than 0.05). PDGF-BB at 10 ng/ml also stimulated 3H-thymidine incorporation and its effect was similar to that induced by PDGF-AB at the same concentration. 17 beta-Estradiol (E2) at 1 microM inhibited 3H-thymidine incorporation by the smooth muscle cells (P less than 0.05). E2 also reduced the stimulatory effect of EGF (15 ng/ml) and PDGF (3 ng/ml). Progesterone at 1 microM either alone or in combination with E2 did not have any effect on 3H-thymidine incorporation or alter the mitogenic action of EGF and PDGF. The effect of EGF and PDGF on cell growth and 3H-thymidine incorporation by myometrial smooth muscle cells was independent of phases of the menstrual cycle. In summary, the results of present studies indicate that human myometrial tissue and myometrial smooth muscle cells in primary culture locally produce EGF and PDGF-AB and contain EGF and PDGF-beta, but not alpha-receptors. Moreover, the myometrial smooth muscle cells in culture respond to the mitogenic action of EGF and PDGF.

Autoradiography↗
PubMed1992

Platelet-derived growth factor (PDGF), epidermal growth factor (EGF), and EGF and PDGF beta-receptors in human endometrial tissue: localization and in vitro action.

Human endometrial tissue and primary stromal cell culture contain immunoreactive epidermal growth factor (EGF), platelet-derived growth factor (PDGF)-AB as well as EGF and PDGF-beta receptors. The immunostaining for EGF, EGF receptor, and PDGF beta-receptor were associated with endometrial luminal and glandular epithelial and stromal cells, whereas only the stromal cells contain immunoreactive PDGF-AB. The immunostaining intensity of EGF, EGF receptor, and PDGF-AB was similar in both phases of the menstrual cycle, whereas, PDGF-beta receptor immunostaining was highest in proliferative phase and considerably reduced, particularly in luminal and glandular epithelial cells in the secretory phase. In addition primary stromal cell cultures express EGF, PDGF-AB, and contain EGF and PDGF-beta receptors, and very low levels of PDGF-alpha receptor. 3H-Thymidine incorporation indicate that after 48 h of incubation in serum-free medium approximately 75-80% of stromal cells are quiescent. Incubation of quiescent stromal cells with 10% fetal bovine serum stimulate 3H-thymidine incorporation in a time-dependent manner reaching maximal after 30-48 h, with a doubling time of 38.2 h. EGF (1.5-15 ng/ml) stimulates 3H-thymidine incorporation by quiescent stromal cells (P less than 0.001). This effect was significantly reduced at concentrations above 15 ng/ml (P less than 0.005). PDGF-AB (3-10 ng/ml) and PDGF-BB (0.5-10 ng/ml) also stimulate 3H-thymidine incorporation in quiescent stromal cells compared to controls (P less than 0.005). The action of EGF (15 ng/ml) and PDGF-AB (10 ng/ml) was time dependent, reaching maximal after 36 and 48 h of incubation (P less than 0.002). Addition of PDGF-AB (10 ng/ml) to EGF (15 ng/ml) significantly enhanced the action of EGF or PDGF-AB used individually (P less than 0.001). 17 beta-estradiol or progesterone at 1 microM did not stimulate 3H-thymidine incorporation, although they were stimulatory in combination (P less than 0.001), they did not alter the action of EGF or PDGF when added in combination. These observations provide further evidence that human endometrial tissue contains specific immunoreactive EGF receptors. It also demonstrates the presence of immunoreactive EGF, PDGF-AB, and PDGF-beta receptors in endometrial tissue as well as stromal cells in primary culture. Both EGF and PDGF are mitogenic for endometrial stromal cells, suggesting an autocrine/paracrine role in modulation of endometrial cell growth and differentiation.

Cell Division↗
PubMed1989

Possible role of prostaglandins in the regulation of mouse myoblasts.

A differentiation-defective mouse myoblast subclone (DD-1), cells of which do not fuse into myotubes nor synthesize muscle-specific proteins, was employed to help define the role of eicosanoids in mouse myoblast differentiation. We observed by hplc, tlc, and radioimmunoassay that the DD-1 cells release strikingly higher levels of cyclooxygenase pathway products prostaglandin E2 and F2 alpha into the culture medium than the parental non-differentiation-defective cells (DZ). In contrast, the levels of 15-hydroxyeicosatetraenoic acid (15-HETE), a lipoxygenase product, and a putatively identified second lipoxygenase product (LLP) did not differ greatly in the two cell types. The DD-1 cells also have strikingly higher levels of cyclooxygenase activity than the parental cells as determined by intact and broken cell assays. Additional fusion-defective clones were isolated on the basis of their flattened appearance and ability to grow in "mitogen-poor" medium and these cells also released strikingly higher levels of prostaglandins E2 and F2 alpha into the growth medium. The "turn on" of the cyclooxygenase pathway in the DD-1 cells and other fusion-defective cells is consistent with the hypothesis that the products of this pathway contribute to the inability of myoblasts to fuse with one another. This hypothesis is supported by the observation that there is a dose-dependent decrease in fusion of DZ cells when PGE2 is added to commitment medium.

Animals↗
PubMed1987

Reconstruction of the chest wall. Procedures and nursing care.

Large defects of the chest wall can be reconstructed with healthy, well-vascularized soft tissue flaps from adjacent areas of the torso. Such treatment extends the capabilities of surgeons and operating room staff and improves the quality of life for many patients with complicated clinical problems. It requires close cooperation among surgeons, operating room staff, and consulting personnel.

Female↗
PubMed1976

Attributional change and the importance of baseline recording a case illustration.

This single case study illustrates how attention to baseline measures prevented premature conclusions regarding the impact of a conditioning procedure upon aggressive, acting-out behavior. Five disruptive behaviors were initially delineated so that frequency distributions could be obtained. During the course of this 15-day observational period, a significant reduction in the number of these aggressive responses was noted. The proposed conditioning procedure was therefore never required. Explanations as well as implications regarding the observed alteration in behavior were discussed.

Acting Out↗
PubMedDate not supplied

Cellular distribution of 5-lipoxygenase and leukotriene receptors in postsurgical peritoneal wound repair.

Products of the eicosanoid pathways, namely prostaglandins and leukotrienes, are known to play a key role in inflammatory and immune responses, as well as other wound cellular activities of wounded tissue. The objective of this study was to determine whether surgically induced intraperitoneal and incisional wounds in the rat express 5-lipoxygenase and contain binding sites for leukotrienes and whether their levels change during the course of healing. With the use of a specific monoclonal antibody generated against 5-lipoxygenase, the enzyme was immunohistochemically localized in various wound cells during postsurgical days 2 to 35. The inflammatory cells within the wound were the major cell types containing 5-lipoxygenase immunoreactive protein, followed by fibroblasts in the incisional and peritoneal fibrous adhesions, striated muscle, and the vasculature. The greatest level of immunostaining was observed during the first 2 weeks after surgery, which decreased to near unwounded levels by day 35. Light microscope autoradiographic binding studies using (3)H-leukotrienes indicated that the peritoneal/incisional wounds and unwounded tissues contain specific (3)H-leukotriene C(4) and (3)H-leukotriene D(4) but not (3)H-leukotriene B(4) binding sites. Quantitative grain analysis (net grain density/100 microm(2)), representing specific (3)H-leukotriene C(4) and (3)H-leukotriene D(4) binding sites calculated for different cell types in the wound and unwounded regions showed that (3)H-leukotriene C(4) binding was highest over the striated muscle proximal to the injury and incisional and peritoneal granulation tissue fibroblasts. The net grain density over these cells increased by 3-, 2.5-, and 2-fold by day 14, respectively, and declined to the control values by day 21 after injury (p < 0.05). The pattern of (3)H-leukotriene D(4) binding was similar to that observed for (3)H-leukotriene C(4), but with a lower density. The grain density for (3)H-leukotriene C(4) and (3)H-leukotriene D(4) in arteriolar endothelial and smooth muscle cells remained unchanged. These data suggest that the products of the lipoxygenase pathway through the presence of their specific receptors may play an important role in peritoneal wound repair and adhesion formation.

Journal Article↗
PubMedDate not supplied

[The "Participatory" Movement].

This study reports the trajectory of the Participatory Movement (MP), which was created in opposition to the policies carried out by the Brazilian Association of Nursing (ABEn). This article, written by the first president elected of the "participatory" movement, presents the principles of the movement, its organization, the struggle for leadership, and the work developed in the first administration.

Brazil↗