C5aR1 activation in mice controls inflammatory eosinophil recruitment and functions in allergic asthma

BACKGROUND

Pulmonary eosinophils comprise at least two distinct populations of resident eosinophils (rEOS) and inflammatory eosinophils (iEOS), the latter recruited in response to pulmonary inflammation. Here, we determined the impact of complement activation on rEOS and iEOS trafficking and function in two models of pulmonary inflammation.

METHODS

BALB/c wild-type and C5ar1^-/- mice were exposed to different allergens or IL-33. Eosinophil populations in the airways, lung, or mediastinal lymph nodes (mLN) were characterized by FACS or immunohistochemistry. rEOS and iEOS functions were determined in vivo and in vitro.

RESULTS

HDM and IL-33 exposure induced a strong accumulation of iEOS but not rEOS in the airways, lungs, and mLNs. rEOS and iEOS expressed C3/C5 and C5aR1, which were significantly higher in iEOS. Initial pulmonary trafficking of iEOS was markedly reduced in C5ar1^-/- mice and associated with less IL-5 production from ILC2 cells. Functionally, adoptively transferred pulmonary iEOS from WT but not from C5ar1^-/- mice-induced airway hyperresponsiveness (AHR), which was associated with significantly reduced C5ar1^-/- iEOS degranulation. Pulmonary iEOS but not rEOS were frequently associated with T cells in lung tissue. After HDM or IL-33 exposure, iEOS but not rEOS were found in mLNs, which were significantly reduced in C5ar1^-/- mice. C5ar1^-/- iEOS expressed less costimulatory molecules, associated with a decreased potency to drive antigen-specific T cell proliferation and differentiation into memory T cells.

CONCLUSIONS

We uncovered novel roles for C5aR1 in iEOS trafficking and activation, which affects key aspects of allergic inflammation such as AHR, ILC2, and T cell activation.

Allergen-Induced C5a/C5aR1 Axis Activation in Pulmonary CD11b+ cDCs Promotes Pulmonary Tolerance through Downregulation of CD40

Activation of the C5/C5a/C5a receptor 1 (C5aR1) axis during allergen sensitization protects from maladaptive T cell activation. To explore the underlying regulatory mechanisms, we analyzed the impact of C5aR1 activation on pulmonary CD11b⁺ conventional dendritic cells (cDCs) in the context of house-dust-mite (HDM) exposure. BALB/c mice were intratracheally immunized with an HDM/ovalbumin (OVA) mixture. After 24 h, we detected two CD11b⁺ cDC populations that could be distinguished on the basis of C5aR1 expression. C5aR1⁻ but not C5aR1⁺ cDCs strongly induced T cell proliferation of OVA-reactive transgenic CD4⁺ T cells after re-exposure to antigen in vitro. C5aR1⁻ cDCs expressed higher levels of MHC-II and CD40 than their C5aR1⁺ counterparts, which correlated directly with a higher frequency of interactions with cognate CD4⁺ T cells. Priming of OVA-specific T cells by C5aR1⁺ cDCs could be markedly increased by in vitro blockade of C5aR1 and this was associated with increased CD40 expression. Simultaneous blockade of C5aR1 and CD40L on C5aR1⁺ cDCs decreased T cell proliferation. Finally, pulsing with OVA-induced C5 production and its cleavage into C5a by both populations of CD11b⁺ cDCs. Thus, we propose a model in which allergen-induced autocrine C5a generation and subsequent C5aR1 activation in pulmonary CD11b⁺ cDCs promotes tolerance towards aeroallergens through downregulation of CD40.

Tissue factor activity on microvesicles from cancer patients

PURPOSE

The expression of active tissue factor (TF) on the surface of microvesicles (MVs) is essential for the activation of the coagulation system and transduction of the signaling pathways in cancer cells. In its use as a biomarker for cancer-associated venous thromboembolism (VTE), TF has shown high expression variability. As a contribution to this discussion, we present a study investigating plasma samples from patients with various progressive tumors at high risk for VTE.

METHODS

Based on our previous study uncovering microvesicles (MVs), the larger ectosome-like extracellular vesicles (EV), as the major source of TF activity in EV preparations, we now determined TF activity on enriched MVs isolated from plasma of cancer patients and compared it with that on MVs from healthy individuals.

RESULTS

We found considerably higher amounts of MVs as well as higher levels of MV-bound TF activities in the plasma of cancer patients. We also show that preparations from plasma of cancer patients have the potency to induce ERK phosphorylation in a human tumor cell line through proteinase-activated receptor two (PAR2) activation.

CONCLUSION

We suggest that MVs instead of whole EV preparations, and TF activity rather than its antigenic quantification should be used in clinical studies for identifying patients with progressive tumors at high risk for VTE.

Short-term high-fat diet feeding protects from the development of experimental allergic asthma in mice

BACKGROUND

A close association between obesity and asthma has been described. The nature of this association remains elusive, especially with respect to allergic asthma. Controversial findings exist regarding the impact of short-term high-fat diet (HFD) feeding on the development of allergic asthma.

OBJECTIVE

To delineate the impact of short-term HFD feeding on the development of experimental allergic asthma.

METHODS

Female C57BL/6JRJ mice were fed with a short-term HFD or chow diet (CD) for 12 weeks. Allergic asthma was induced by intraperitoneal OVA/alum sensitization followed by repeated OVA airway challenges. We determined airway hyperresponsiveness (AHR) and pulmonary inflammation by histologic and flow cytometric analysis of immune cells. Furthermore, we assessed the impact of HFD on dendritic cell (DC)-mediated activation of T cells.

RESULTS

Female mice showed a mild increase in body weight accompanied by mild metabolic alterations. Upon OVA challenge, CD-fed mice developed strong AHR and airway inflammation, which were markedly reduced in HFD-fed mice. Mucus production was similar in both treatment groups. OVA-induced increases in DC and CD4⁺ T-cell recruitment to the lungs were significantly attenuated in HFD-fed mice. MHC-II expression and CD40 expression in pulmonary CD11b⁺ DCs were markedly lower in HFD-fed compared to CD-fed mice, which was associated in vivo with a decreased T helper (Th) 1/17 differentiation and Treg formation without impacting Th2 differentiation.

CONCLUSIONS/CLINICAL RELEVANCE

These findings suggest that short-term HFD feeding attenuates the development of AHR, airway inflammation, pulmonary DC recruitment and MHC-II/CD40 expression leading to diminished Th1/17 but unchanged Th2 differentiation. Thus, short-term HFD feeding and associated metabolic alterations may have protective effects in allergic asthma development.

Extracellular Vesicles: Subcellular Organelles With the Potential to Spread Cancer Resistance

Although modern anticancer drugs have made great progress in disease treatment, the occurrence of drug resistance often leads to treatment failure. Understanding the molecular basis of resistance mechanisms is important to determine prognosis and develop strategies for circumvention. In this context, subcellular vesicles released by cancer cells have been identified to mediate cellular resistance by various mechanisms. Such extracellular vesicles (EVs) can be subdivided into exosomes and ectosomes based on their size, cargo, and mechanism of formation. The unveiling of EV-targeted treatment options depends on a sound knowledge on EV biology including biogenesis, release, targeting to recipient cells, and uptake. In this review, we focus on EVs as mediators of cancer drug resistance with a particular emphasis on the distinction of exosomes and ectosomes.

Heterogeneity of microvesicles from cancer cell lines under inflammatory stimulation with TNF-α

Microvesicles (MVs) represent a subgroup of extracellular vesicles (EVs) emerging from various cells by blebbing of their outer membrane. Therefore, they share features such as membrane composition and antigenicity with their parental cells. Released by many immune and tumor cells, MVs act as intercellular messengers, account for horizontal gene transfer and can activate the coagulation system. With the aim to investigate their relevance for tumor cell biology, we characterized MVs released by human tumor cell lines of various origins in the absence or presence of TNF-α. After stimulation, we used the combination of low and high-speed centrifugation to enrich MVs from cell culture supernatants. We analyzed the presentation of phosphatidylserine (PS) and tissue factor (TF) activity on the cell surface and investigated their potency to induce tumor cell migration. In all tumor cell lines, TNF-α stimulation enhanced the release of MVs. While the expression of PS was universally increased, an elevated activity of procoagulant TF could be detected on MVs from lung, pancreatic, and colon carcinoma, but not from breast and ovarian cancer cell lines. Functionally, TNF-α stimulation significantly increased the potency of MVs to induce tumor cell migration. In conclusion, inflammatory conditions promote the release of MVs with increased procoagulant activity from tumor cell lines in vitro. PS-containing and TF-expressing MVs may account for systemic activation of the coagulation system as seen in cancer patients and, since they induce tumor cell migration, they may serve as biomarkers for tumor progression.

Monitoring C5aR2 Expression Using a Floxed tdTomato-C5aR2 Knock-In Mouse

The biological significance of C5a receptor [(C5aR)2/C5L2], a seven-transmembrane receptor binding C5a and C5adesArg, remains ill-defined. Specific ligation of C5aR2 inhibits C5a-induced ERK1/2 activation, strengthening the view that C5aR2 regulates C5aR1-mediated effector functions. Although C5aR2 and C5aR1 are often coexpressed, a detailed picture of C5aR2 expression in murine cells and tissues is still lacking. To close this gap, we generated a floxed tandem dye (td)Tomato-C5aR2 knock-in mouse that we used to track C5aR2 expression in tissue-residing and circulating immune cells. We found the strongest C5aR2 expression in the brain, bone marrow, and airways. All myeloid-derived cells expressed C5aR2, although with different intensities. C5aR2 expression in blood and tissue neutrophils was strong and homogeneous. Specific ligation of C5aR2 in neutrophils from tdTomato-C5aR2 mice blocked C5a-driven ERK1/2 phosphorylation, demonstrating functionality of C5aR2 in the reporter mice. In contrast to neutrophils, we found tissue-specific differences in C5aR2 expression in eosinophils, macrophages, and dendritic cell subsets. Naive and activated T cells stained negative for C5aR2, whereas B cells from different tissues homogeneously expressed C5aR2. Also, NK cell subsets in blood and spleen strongly expressed C5aR2. Activation of C5aR2 in NK cells suppressed IL-12/IL-18-induced IFN-γ production. Intratracheal IL-33 challenge resulted in decreased C5aR2 expression in pulmonary eosinophils and monocyte-derived dendritic cells. In summary, we provide a detailed map of murine C5aR2 immune cell expression in different tissues under steady-state conditions and upon pulmonary inflammation. The C5aR2 knock-in mouse will help to reliably track and conditionally delete C5aR2 expression in experimental models of inflammation.

Monitoring C3aR Expression Using a Floxed tdTomato-C3aR Reporter Knock-in Mouse

C3a exerts multiple biologic functions through activation of its cognate C3a receptor. C3^-/- and C3aR^-/- mice have been instrumental in defining important roles of the C3a/C3aR axis in the regulation of acute and chronic inflammatory diseases, including ischemia/reperfusion injury, allergic asthma, autoimmune nephritis, and rheumatoid arthritis. Surprisingly little is known about C3aR expression and function in immune and stromal cells. To close this gap, we generated a floxed tandem-dye Tomato (tdTomato)-C3aR reporter knock-in mouse, which we used to monitor C3aR expression in cells residing in the lung, airways, lamina propria (LP) of the small intestine, brain, visceral adipose tissue, bone marrow (BM), spleen, and the circulation. We found a strong expression of tdTomato-C3aR in the brain, lung, LP, and visceral adipose tissue, whereas it was minor in the spleen, blood, BM, and the airways. Most macrophage and eosinophil populations were tdTomato-C3aR⁺ Interestingly, most tissue eosinophils and some macrophage populations expressed C3aR intracellularly. BM-derived dendritic cells (DCs), lung-resident cluster of differentiation (CD) 11b⁺ conventional DCs (cDCs) and monocyte-derived DCs, LP CD103⁺, and CD11b⁺ cDCs but not pulmonary CD103⁺ cDCs and splenic DCs were tdTomato-C3aR⁺ Surprisingly, neither BM, blood, lung neutrophils, nor mast cells expressed C3aR. Similarly, all lymphoid-derived cells were tdTomato-C3aR^-, except some LP-derived type 3 innate lymphoid cells. Pulmonary and LP-derived epithelial cells expressed at best minor levels of C3aR. In summary, we provide novel insights into the expression pattern of C3aR in mice. The floxed C3aR knock-in mouse will help to reliably track and conditionally delete C3aR expression in experimental models of inflammation.

Accumulation of pulmonary vacuolated eosinophils in experimental allergic asthma that synergize with dendritic cells to induce Th-17 cells

Eosinophils are considered a homogenous cell population, contributing to the allergic asthma phenotype by promoting mucus hypersecretion and airway hyperresponsiveness. Here, we identified a previously unrecognized vacuolated CD11cdim eosinophilic population (vEOS) which accmulates exclusively in the lung tissue and in mediastinal lymph nodes but not in the airways in a house dust mite-mediated allergic asthma model and an IL-33 mediated pulmonary inflammation. In addition to the vEOS, we found classical SiglecF+CD11c− eosinophils (EOS) in the airways and the lung. Both cell types shared typical structural features of eosinophils and expressed CCR3. In contrast to EOS, vEOS expressed higher levels of the CD11a, CD11b and CD18 integrins. Immunofluorescence microscopy revealed that vEOS were located exclusively near arteries and airways, where they were in close contact with T cells. Moreover, vEOS took up antigen and expressed costimulatory molecules more efficiently than EOS. Consequently, in co-culture experiments with OVA-TCR transgenic T cells, vEOS and dendritic cells (DCs) drove T cell proliferation. However, in the presence of vEOS, T cells divided more frequently than in co-culture with DCs. Further, T cell activation in response to co-culture with vEOS together with DCs markedly enhanced IL-17 but not IL-13 production.

Collectively, our data demonstrate that vEOS are an important subset of eosinophils, which differ from EOS in their location and their ability to activate T cells. Further, they suggest that cross-talk between vEOS and DCs might be a crucial step for the induction of Th17 cells in allergic asthma. Thus, vEOS may serve as an important target for Th17-associated steroid-resistant asthma.

Differential regulation of C5a receptor 1 in innate immune cells during the allergic asthma effector phase

C5a drives airway constriction and inflammation during the effector phase of allergic asthma, mainly through the activation of C5a receptor 1 (C5aR1). Yet, C5aR1 expression on myeloid and lymphoid cells during the allergic effector phase is ill-defined. Recently, we generated and characterized a floxed green fluorescent protein (GFP)-C5aR1 knock-in mouse. Here, we used this reporter strain to monitor C5aR1 expression in airway, pulmonary and lymph node cells during the effector phase of OVA-driven allergic asthma. C5aR1 reporter and wildtype mice developed a similar allergic phenotype with comparable airway resistance, mucus production, eosinophilic/neutrophilic airway inflammation and Th2/Th17 cytokine production. During the allergic effector phase, C5aR1 expression increased in lung tissue eosinophils but decreased in airway and pulmonary macrophages as well as in pulmonary CD11b⁺ conventional dendritic cells (cDCs) and monocyte-derived DCs (moDCs). Surprisingly, expression in neutrophils was not affected. Of note, moDCs but not CD11b⁺ cDCs from mediastinal lymph nodes (mLN) expressed less C5aR1 than DCs residing in the lung after OVA challenge. Finally, neither CD103⁺ cDCs nor cells of the lymphoid lineage such as Th2 or Th17-differentiated CD4⁺ T cells, B cells or type 2 innate lymphoid cells (ILC2) expressed C5aR1 under allergic conditions. Our findings demonstrate a complex regulation pattern of C5aR1 in the airways, lung tissue and mLN of mice, suggesting that the C5a/C5aR1 axis controls airway constriction and inflammation through activation of myeloid cells in all three compartments in an experimental model of allergic asthma.

Origin, Localization, and Immunoregulatory Properties of Pulmonary Phagocytes in Allergic Asthma

Allergic asthma is a chronic inflammatory disease of the airways that is driven by maladaptive T helper 2 (Th2) and Th17 immune responses against harmless, airborne substances. Pulmonary phagocytes represent the first line of defense in the lung where they constantly sense the local environment for potential threats. They comprise two distinct cell types, i.e., macrophages and dendritic cells (DC) that differ in their origins and functions. Alveolar macrophages quickly take up most of the inhaled allergens, yet do not deliver their cargo to naive T cells sampling in draining lymph nodes. In contrast, pulmonary DCs instruct CD4(+) T cells develop into Th2 and Th17 effectors, initiating the maladaptive immune responses toward harmless environmental substances observed in allergic individuals. Unraveling the mechanisms underlying this mistaken identity of harmless, airborne substances by innate immune cells is one of the great challenges in asthma research. The identification of different pulmonary DC subsets, their role in antigen uptake, migration to the draining lymph nodes, and their potential to instruct distinct T cell responses has set the stage to unravel this mystery. However, at this point, a detailed understanding of the spatiotemporal resolution of DC subset localization, allergen uptake, processing, autocrine and paracrine cellular crosstalk, and the humoral factors that define the activation status of DCs is still lacking. In addition to DCs, at least two distinct macrophage populations have been identified in the lung that are either located in the airway/alveolar lumen or in the interstitium. Recent data suggest that such populations can exert either pro- or anti-inflammatory functions. Similar to the DC subsets, detailed insights into the individual roles of alveolar and interstitial macrophages during the different phases of asthma development are still missing. Here, we will provide an update on the current understanding of the origin, localization, and function of the diverse pulmonary antigen-presenting cell subsets, in particular with regard to the development and regulation of allergic asthma. While most data are from mouse models of experimental asthma, we have also included available human data to judge the translational value of the findings obtained in experimental asthma models.

Monitoring and cell-specific deletion of C5aR1 using a novel floxed GFP-C5aR1 reporter knock-in mouse

Many of the biological properties of C5a are mediated through activation of its receptor (C5aR1), the expression of which has been demonstrated convincingly on myeloid cells, such as neutrophils, monocytes, and macrophages. In contrast, conflicting results exist regarding C5aR1 expression in dendritic cells (DCs) and lymphoid lineage cells. In this article, we report the generation of a floxed GFP-C5aR1 reporter knock-in mouse. Using this mouse strain, we confirmed strong C5aR1 expression in neutrophils from bone marrow, blood, lung, and spleen, as well as in peritoneal macrophages. Further, we show C5aR1 expression in lung eosinophils, lung- and lamina propria-resident and alveolar macrophages, bone marrow-derived DCs, and lung-resident CD11b(+) and monocyte-derived DCs, whereas intestinal and pulmonary CD103(+) DCs stained negative. Also, some splenic NKT cells expressed GFP, whereas naive NK cells and B2 cells lacked GFP expression. Finally, we did not observe any C5aR1 expression in naive or activated CD4(+) Th cells in vitro or in vivo. Mating the floxed GFP-C5aR1 mouse strain with LysMCre mice, we were able to specifically delete C5aR1 in neutrophils and macrophages, whereas C5aR1 expression was retained in DCs. In summary, our findings suggest that C5aR1 expression in mice is largely restricted to cells of the myeloid lineage. The novel floxed C5aR1 reporter knock-in mouse will prove useful to track C5aR1 expression in experimental models of acute and chronic inflammation and to conditionally delete C5aR1 in immune cells.

Distinct roles of the anaphylatoxins C3a and C5a in dendritic cell-mediated allergic asthma

Conventional dendritic cells (cDC) are necessary and sufficient to drive mixed maladaptive Th2/Th17 immune responses toward aeroallergens in experimental allergy models. Previous studies suggest that the anaphylatoxin C3a promotes, whereas C5a protects from the development of maladaptive immunity during allergen sensitization. However, only limited evidence exists that such effects are directly mediated through anaphylatoxin-receptor signaling in cDCs. In this study, we assessed the impact of C3a and C5a on cDC-mediated induction pulmonary allergy by adoptively transferring house dust mite (HDM)-pulsed bone marrow-derived DCs (BMDC) from wild-type (WT) C3aR(-/-), C5aR1(-/-), or C3aR(-/-)/C5aR1(-/-) into WT mice. Transfer of HDM-pulsed WT BMDCs promoted a strong asthmatic phenotype characterized by marked airway resistance, strong Th2 cytokine, and mucus production, as well as mixed eosinophilic and neurophilic airway inflammation. Surprisingly, C3aR(-/-) cDCs induced a strong allergic phenotype, but no IL-17A production, whereas HDM-pulsed C5aR1(-/-) cDCs failed to drive pulmonary allergy. Transfer of C3aR(-/-)/C5aR1(-/-) cDCs resulted in a slightly reduced allergic phenotype associated with increased IFN-γ production. Mechanistically, C3aR and C5aR1 signaling is required for IL-23 production from HDM-pulsed BMDCs in vitro. Furthermore, C3aR(-/-) BMDCs produced less IL-1β. The mechanisms underlying the failure of C5aR1(-/-) BMDCs to induce experimental allergy include a reduced capability to migrate into the lung tissue and a decreased potency to direct pulmonary homing of effector T cells. Thus, we uncovered a crucial role for C5a, but only a minor role for C3a in BMDC-mediated pulmonary allergy, suggesting that BMDCs inappropriately reflect the impact of complement on lung cDC-mediated allergic asthma development.

[How do intraoperative complications effect adhesion formation after laparoscopic cholecystectomy: a comparative animal study]

BACKGROUND

The aim of this study was to evaluate the extent of postoperative formation of adhesions following laparoscopic and open cholecystectomy.

MATERIAL AND METHODS

60 experimental laparoscopic cholecystectomies (LC) were performed in dogs by qualified surgeons to learn laparoscopic technique. To assess the relationship between complications occurred during the operation (bleeding, laceration of the liver bed or gallbladder perforation) and the formation of adhesions surviving animals were divided into 4 groups according to the type of complication. We assessed the results during second-look laparoscopy 4 weeks following LC using the adhesion index (AI: 0-4 score). Animals were then sacrificed to measure the extent of adhesions. As a control group open cholecystectomy was performed in 15 dogs without intraoperative complications. Mann-Whitney Rank Sum test and Dunn's Method were used for statistical analysis.

RESULTS

No adhesions were observed in the laparoscopic group without intraoperative complications. In all dogs with bleeding or laceration of the liver bed maintained by electrocoagulation, adhesions developed. Formation of adhesion in these groups was significantly higher than in "ideal LC" or in case of gallbladder perforation (P < 0.01). All animals in the control group developed significantly more adhesions compared to the experimental group (p < 0.05).

CONCLUSION

LC produces less adhesion compared to conventional open technique. Complications such as bleeding or laceration of the liver bed during LC can increase the formation of adhesions. No formation of adhesions can be related to gallbladder perforation during LC.

[Effect of pentoxifylline on the healing of experimental anastomosis of the left colon in rats]

The healing of colonic anastomoses is determined by several factors such as microcirculation, the strength of the inflammatory response, and the time required for regeneration. We investigated the effects of pentoxifylline--a drug which improves microcirculation and modulates leukocyte functions--on the healing of experimental anastomosis on the left colon of rats. As a result of drug treatment (0.25 mg/100 g, i.p.) in Group I anastomosis bursting pressure (ABP) was by 56 +/- 17% higher at day 2 than in controls with no pentoxifylline treatment. On the 5th postoperative day in Group I, ABP reached 80 +/- 8% the value for the intact colon (218 +/- 21 mmHg), whereas respective value in the control (untreated) group was only 47 +/- 7%. In Group II (pentoxifylline: 2 mg/100 g, i.p.) ABP was by 55 +/- 10% and by 73 +/- 8% higher than control values at postoperative days 1 and 2, respectively. At day 2, in Group I colonic blood flow measured at the anastomosis line by 86Rb uptake technique was significantly higher than in the untreated controls (0.18 +/- 0.01 ml/min vs. 0.14 +/- 0.01 ml/min, (p < 0.02). Blood flow measured in colon tissue above and below the anastomosis changed differently. Pentoxifylline treatment also suppressed the peritoneal inflammatory response assessed with peritoneal reaction index (2.0 +/- 0.3 vs. 1.1 +/- 0.2, p < 0.01). The results of the present study show that pentoxifylline treatment shortens the time needed for the healing of colonic anastomosis. These observations suggest that pentoxifylline medication can prevent failure of colonic anastomoses.

[Esophageal anastomosis--based on the experience with 1460 operations]

The authors reviewed the clinical records of 1460 patients with esophageal anastomoses, the operations performed in their institute between 1973 and 2000. Surgical outcome was assessed with incidence of anastomotic leaks and overall mortality. Hand-sewn anastomoses were performed by inserting single layer interrupted monofil steel wire (507), PDS (232) or Vicryl (65) sutures and circular stapler (EEA, Ethicon) was used in 656 patients. 453 (65 cervical, 293 thoracic, and 95 abdominal) anastomoses performed between 1995 and 2000 were analyzed separately. During this 6-year period, the majority of operations (88%) were performed because of esophageal malignancy (squamous cell carcinoma of the esophagus or adenocarcinoma of the cardia). Surgery was performed for benign disease (e.g. stricture, perforation, and stage IV achalasia) in 12%. The incidence of anastomotic leak was the highest (20%) after cervical anastomosis, compared to a 4.4% or 1% associated with thoracic or abdominal anastomoses. These differences are statistically significant (p < 0.001). The rate of anastomotic leakage was strongly connected to surgical technique: it was 15% in hand-sewn anastomoses and only 4.4% with stapled anastomosis. During the 6-year period overall mortality was 6.6%t.

[Rare late complication after subtotal esophagectomy]

We report a case of a peptic ulcer developed in the stomach tube used for the replacement of the esophagus. The patient was a 60 years old female who had undergone subtotal esophagectomy for mid esophageal malignancy, with intrapleural stomach replacement. Urgent endoscopy revealed an excavated, bleeding ulcer in the thoracic part of the stomach. After unsuccessful medical treatment urgent operation was performed via right thoracotomy. Opening the stomach an ulcer was found on the posterior wall of the stomach, it was penetrating to the right atrium of the heart. The bleeding was controlled by suturing the atrium wall. The patient treated with i.v. Omeprazol in the postoperative period. On the 21st postoperative day a rebleeding occurred causing shock. After reoperation the patient died. This complication is very rare. We emphasise the importance of postoperative pH measurement investigations showing the presence of duodenogastric reflux disease.

Response to the sexual pheromone and wounding in the green alga volvox: induction of an extracellular glycoprotein consisting almost exclusively of hydroxyproline

The extracellular matrix (ECM) of Volvox is modified during development or in response to external stimuli, like the sex-inducing pheromone. It has recently been demonstrated that a number of genes triggered by the sex-inducing pheromone are also inducible by wounding. By differential screening of a cDNA library, a novel gene was identified that is transcribed in response to the pheromone. Its gene product was characterized as an ECM glycoprotein with a striking feature: it exhibits a hydroxyproline content of 68% and therefore is an extreme member of the family of hydroxyproline-rich glycoproteins (HRGPs). HRGPs are known as constituents of higher plant ECMs and seem to function as structural barriers in defense responses. The Volvox HRGP is also found to be inducible by wounding. This indicates that the wound response scenarios of higher plants and multicellular green algae may be evolutionary related.

Therapeutic results with Cerebrolysin in the treatment of dementia

BACKGROUND

In the present study patients suffering from dementia were treated with an infusion therapy using the neurotrophic drug Cerebrolysin. The effectiveness of the therapy was examined under conditions of daily clinical practice.

METHODS

645 Patients were treated with 30 ml Cerebrolysin daily. The average period of treatment was 17.8 days. Prior to treatment patients were diagnosed according to DSM-III-R. In addition a differential diagnostic examination using the Hachinski Ischemic Score was performed. Clinical symptoms and the Clinical Global Impression (CGI) were determined before and after therapy.

RESULTS

Cerebrolysin therapy led to a significant (p < 0.001) improvement in memory for 62% of the patients. 65% showed improvement in concentration, 50% in mood and fatigue, and 47% improved in vertigo. An improvement in the Clinical Global impression was observed in approximately 80% of the patients. The improvement of symptoms was significantly larger (p < 0.05) in younger, less afflicted patients than in the older, more seriously ill patients. The unusual good tolerance of Cerebrolysin was especially noteworthy.

CONCLUSIONS

The present study confirms the results of earlier clinical studies with Cerebrolysin in the treatment of Alzheimer patients and patients with vascular dementia in which similar responder rates were observed. The significant dependence of therapeutic success on the length and severity of illness confirms that timely pharmacological intervention leads to best therapeutic results.

The trental treatment prevents the reduction of superoxide dismutase enzyme (SOD) activity in rats after colon surgery

The authors tested the effects of the pentoxiphyllin (px, Trental) pre-treatment upon the superoxide dismutase activity of the left colonpart anastomosis of rats. It has been found that the SOD activity of the proximal (4.9 U/g), the anastomical area (1.9 U/g) and the distal (3.1 U/g) intestinal segments considerably decreased, compared to the control (9.16 U/g). In the operated and pre-treated animals with Trental, the SOD activity of all the three intestinal segments increased (proximal 15.5-anastomosis 5.7-distal 8.9 U/g) compared to the non treated group.

Effects of streptozotocin-induced diabetes on neurogenic inflammation of gingivomucosal tissue in rat

It has been suggested that the unmyelinated small diameter afferent nociceptive C-fibres are impaired in diabetes mellitus. We have recently demonstrated that these fibres are the prerequisite for neurogenic inflammation induced by mechanical or chemical irritations. These experiments were designed to characterize the neurogenic inflammatory responses of gingivomucosal tissue in the early phase of experimental induced diabetes mellitus in rat. Effect of dental ligature on the gingivomucosal (GM) vascular permeability was studied in control rats and in rats pretreated with streptozotocin at d 7 and 14 following streptozotocin administration. In separate groups of control and streptozotocin diabetic rats studies were also performed to investigate the effect of local capsaicin application on GM vascular permeability on d 14. Vascular permeability was assessed by means of Evans blue extravasation. The ligature placed around the mandibular left first molar caused a significant increase vascular permeability of GM tissue on the ipsilateral side on both d 7 and 14 after the ligation in control rats. In streptozotocin diabetic rats on d 7, there was also a significant elevation of Evans blue extravasation in the tissue tested on the ligature side. However, on d 14 the ligation failed to produce any changes in Evans blue extravasation on the ipsilateral side, i.e. no difference in GM vascular permeability could be recorded between the two sides in streptozotocin diabetic rats. Topical capsaicin administration produced significant Evans blue extravasation in GM tissue of control rats compared to that observed in diabetic rats on d 14 after streptozotocin treatment. Electron microscopic and light microscopic studies demonstrated fibre degeneration of the C neurones and less inflammatory cells in streptozotocin-induced diabetes in the gingivomucosal tissue. These findings appear to indicate that the inflammatory responses induced by mechanical (dental ligature) and/or chemical irritants (topical application of capsaicin) in the gingivomucosal tissue are altered in streptozotocin diabetic rats and this alteration is due to the diabetes-induced damage to the unmyelinated C fibres.

Neurogenic component in ligature-induced periodontitis in the rat

Effect of ligation on the vascular permeability in the gingiva and alveolar mucosa encircling the mandibular left 1st molar was studied in rats with and without capsaicin pretreatment. Vascular permeability was assessed by the Evans blue extravasation. Ligation caused a significant augmentation in vascular permeability of the gingivomucosal tissue at day 8 (right: 18.14 +/- 1.68 micrograms g-1; left (ligature): 38.21 +/- 2.43 micrograms g-1, n = 8, p < 0.001) and at day 14 (right: 20.31 +/- 1.71 micrograms g-1: left (ligature): 36.98 +/- 2.73 micrograms g-1, n = 8, p < 0.001). 4 days after ligation, no difference could be observed in vascular permeability in the oral mucosa of the ligated side (left: 23.14 +/- 1.21 micrograms g-1) as compared to the side without ligature (right: 23.5 +/- 1.45 micrograms g-1, n = 8, NS). There was no elevation of vascular permeability of gingivomuscosal tissue around the ligation in rats pretreated with capsaicin either in newborn age (right: 23.92 +/- 1.76 micrograms g-1; left (ligature): 23.51 +/- 2.16 micrograms g-1, n = 8, NS) or in adult age (right: 20.61 +/- 1.62 micrograms g-1; left (ligature): 20.85 +/- 1.07 micrograms g-1, n = 8, NS). Light microscopical studies of oral mucosa revealed, that 8 and 14 days after the ligature placed around the mandibular left 1st molar of the rat, there resulted an accumulation of inflammatory cells in the connective tissue.(ABSTRACT TRUNCATED AT 250 WORDS)