Peritoneal adhesions (PA) represent a major cause of morbidity in pediatric surgical patients. Th... more Peritoneal adhesions (PA) represent a major cause of morbidity in pediatric surgical patients. The pathogenesis is still largely unknown. A possible role could be played by foreign bodies (FB) accidentally contaminating the operative field during surgery. We report a histologic study of PA in a rat model and in children, investigating the role of FB in their formation. Abdominal adhesions were studied in 18 rats. In 6 (group A) we performed a laparotomy and rubbed the visceral and parietal peritoneum with a cotton bud. In 6 (group B) we performed a minimal laparotomy and injected powdered autologous and heterologous material into the peritoneal cavity, avoiding any peritoneal abrasions. In 6 (group C) we performed a laparotomy and applied both treatment methods, i.e., rubbing and injection of FB. After 1 month, at autopsy rats were classified according to the presence and grade of surgical adhesions. Twenty-two PA were also collected from seven children undergoing abdominal surgery ...
A major gene causing Hirschsprung's disease was recently mapped in 10q11.2. Its physical ... more A major gene causing Hirschsprung's disease was recently mapped in 10q11.2. Its physical localization was restricted to a 250-Kb interval containing the RET proto-oncogene (REarranged during Transfection). In 1994, point mutations affecting the RET proto-oncogene were identified in patients with Hirschsprung's disease. The authors present an immunohistochemical study on the expression and localization of the Ret protein (a receptor tyrosine kinase, which is the RET proto-oncogene product) in the intestinal plexuses of patients with Hirschsprung's disease. Ninety-two full-thickness intestinal wall pieces from 29 pediatric patients were studied (19 cases of classic Hirschsprung's disease, 5 of total colonic aganglionosis, and 5 controls). Ret protein immunohistochemical localization was obtained using c-Ret R5, anti-Ret K and anti-Ret C antibodies, respectively, against the extracellular domain, the tyrosine kinase domain, and the carboxy-terminal 20 amino acids of the Ret protein. A diffuse granular staining was present in the ganglia of normal colon, whereas the small ganglia of the hypoganglionic colon showed a reduced number of ganglion cells that were strongly stained with c-Ret R5 MoAb. A reduced synthesis of Ret protein was shown in the ganglionic and hypoganglionic segments of two cases of this series, the first with a complete deletion of the RET proto-oncogene and the second with a frameshift mutation and a stop codon in the extracellular domain. The activity of the receptor tyrosine kinases (RTKs) in intestinal ganglion cells was investigated using antiphosphotyrosine antibodies. A very low tyrosine kinase activity was shown in the small ganglia of the hypoganglionic segment.(ABSTRACT TRUNCATED AT 250 WORDS)
Neural crest (NC) cells differentiate IN VITRO into neuroblasts, precursors of the enteric nervou... more Neural crest (NC) cells differentiate IN VITRO into neuroblasts, precursors of the enteric nervous system (ENS), when stimulated by specific agents. We developed a study aimed at establishing whether NC-derived neuroblasts can survive and colonise IN VIVO when injected into a recipient mouse gut. The neuroblast precursors of the ENS were obtained from the vagal portion of the neural tubes of 296 CD-1 and GTROSA26 mouse embryos. The embryonic cells of GTROSA26 mice are identifiable through beta-galactosidase activity which allows recognition by blue staining. The host used in this study was the DOM/+ mouse, an animal model for Hirschsprung's disease (aganglionic megacolon). DOM/+ mouse pups (n = 43) received NC-derived cells inoculated into the seromuscular layer of the gut (33/43) or directly into the peritoneal abdominal cavity (10/43). All DOM/+ mice survived the procedure and were sacrificed after 7 or 14 days. Histochemical staining detected implanted cells in all mice. These showed specific myenteric colonisation into the aganglionic and ganglionic gut. The striking result of this study was the specific tropism of the injected NC-derived cells to target sites under the action of unknown chemotactic agents. This experimental procedure might represent a possible treatment option for specific forms of human ENS anomaly such as total intestinal aganglionosis.
Aim of this study was to investigate, for the first time, whether isolated newborn mouse enteric ... more Aim of this study was to investigate, for the first time, whether isolated newborn mouse enteric plexus could induce in vitro differentiation of the vagal neural crest-derived cells into enteric neuroblasts. Fragments of the myenteric plexus were isolated from the small intestine of 6-day-old Swiss mice and were collected and stored in DMEM-F12 medium, then cultured on polymerized human fibronectin layer. The vagal portion of the neural tube, isolated from a 9.5-day-old Swiss mouse embryo, was put in the same chamber slides where the isolated myenteric plexus had been cultured for 3 days. The vagal neural crest-derived cells migrated onto the polymerized human fibronectin layer and formed a crown of cells around the neural tube. After 6 days, the cultures were stopped and studied immunohistochemically for anti-NF160 KD, anti-TH, and RetR5 antibodies to analyse the differentiation stage of the cultured cells. Analysis of results included the comparison of two culture groups: Group 1, used as control, in which vagal neural crest-derived cells were put in DMEM-F12, supplemented only with 10 % of FCS; Group 2, in which vagal neural crest-derived cells were put in the same medium as Group 1, with the addition of myenteric plexus fragments isolated from newborn mice to form the co-culture. The following results were obtained: in Group 1 the neural tubes originated a cell population strongly positive for anti-NF160 and anti-TH Ab, but negative for RetR5 Ab. This positivity was found both in the cells adjacent to the neural tube and in those migrating from it distally. The Group 2 originated cells, which after migration were positive for anti-NF160 and for anti-TH antibodies. In addition, in this culture group, the cells which migrated from the neural tube were positive for anti-RetR5 antibody. The co-culture used in this study induces the differentiation of vagal stem cells into enteric neuroblasts, cells TH+ and RetR5+. These cells, after reaching the embryonic intestine, migrate to colonize the hindgut and form the ENS. Therefore this biotechnology seems a good method to obtain in vitro enteric precursors of ENS.
T lymphocytes arise in the thymus and seed to peripheral lymphoid organs as fully functional cell... more T lymphocytes arise in the thymus and seed to peripheral lymphoid organs as fully functional cells at the time of exit. In humans, the thymus begins to function very early in ontogeny and releases large numbers of T cells before the time of birth. However, the vast majority of developing thymocytes (>95%) die within the thymus as a result of stringent selection processes. Positive selection imposes self-MHC-restriction on thymocytes and dictates the MHC-restricted repertoire of post-thymic T cells. Negative selection results in deletion of autoreactive cells. Both types of selection depend on cell to cell contracts and on the presence of appropriate growth factors which are still largely undetermined. Cell to cell contacts occur between developing thymocytes and cells of the thymic microenvironment (accessory cells), and are mediated by several receptor/ligand interactions which subserve the function of establishing and stabilizing these contacts. Besides MHC-TCR interactions, adhesion molecules are important for thymocyte maturation, selection and activation, and for the export and peripheral homing of mature T cells produced in the thymus. Here we describe a novel integrin involved in thymocyte-thymic epithelial cell interactions.
Background Breast cancer is a major malignancy affecting females worldwide. It is the most common... more Background Breast cancer is a major malignancy affecting females worldwide. It is the most common cause of death from cancer in women. Cell lines are widely used in laboratory research and particularly as in vitro models in cancer research. But we found that the routinely used breast cancer cell lines were mostly derived from Caucasians or African-Americans. There were few standard models to study the pathogenic mechanism at molecular level and cell signaling pathway of breast cancer for Asian patients. It is quite necessary to establish new breast cancer cell lines from xanthoderm to study the pathogenic mechanism and therapeutic methods. Results Three new breast cancer cell lines, designated BC-019, BC-020 and BC-021, were successfully established and characterized from breast invasive ductal carcinoma tissues of three Chinese female patients. These new cell lines growing as adherent monolayer with characteristic epithelial morphology could be maintained continuously in vitro, and...
Peritoneal adhesions (PA) represent a major cause of morbidity in pediatric surgical patients. Th... more Peritoneal adhesions (PA) represent a major cause of morbidity in pediatric surgical patients. The pathogenesis is still largely unknown. A possible role could be played by foreign bodies (FB) accidentally contaminating the operative field during surgery. We report a histologic study of PA in a rat model and in children, investigating the role of FB in their formation. Abdominal adhesions were studied in 18 rats. In 6 (group A) we performed a laparotomy and rubbed the visceral and parietal peritoneum with a cotton bud. In 6 (group B) we performed a minimal laparotomy and injected powdered autologous and heterologous material into the peritoneal cavity, avoiding any peritoneal abrasions. In 6 (group C) we performed a laparotomy and applied both treatment methods, i.e., rubbing and injection of FB. After 1 month, at autopsy rats were classified according to the presence and grade of surgical adhesions. Twenty-two PA were also collected from seven children undergoing abdominal surgery ...
A major gene causing Hirschsprung's disease was recently mapped in 10q11.2. Its physical ... more A major gene causing Hirschsprung's disease was recently mapped in 10q11.2. Its physical localization was restricted to a 250-Kb interval containing the RET proto-oncogene (REarranged during Transfection). In 1994, point mutations affecting the RET proto-oncogene were identified in patients with Hirschsprung's disease. The authors present an immunohistochemical study on the expression and localization of the Ret protein (a receptor tyrosine kinase, which is the RET proto-oncogene product) in the intestinal plexuses of patients with Hirschsprung's disease. Ninety-two full-thickness intestinal wall pieces from 29 pediatric patients were studied (19 cases of classic Hirschsprung's disease, 5 of total colonic aganglionosis, and 5 controls). Ret protein immunohistochemical localization was obtained using c-Ret R5, anti-Ret K and anti-Ret C antibodies, respectively, against the extracellular domain, the tyrosine kinase domain, and the carboxy-terminal 20 amino acids of the Ret protein. A diffuse granular staining was present in the ganglia of normal colon, whereas the small ganglia of the hypoganglionic colon showed a reduced number of ganglion cells that were strongly stained with c-Ret R5 MoAb. A reduced synthesis of Ret protein was shown in the ganglionic and hypoganglionic segments of two cases of this series, the first with a complete deletion of the RET proto-oncogene and the second with a frameshift mutation and a stop codon in the extracellular domain. The activity of the receptor tyrosine kinases (RTKs) in intestinal ganglion cells was investigated using antiphosphotyrosine antibodies. A very low tyrosine kinase activity was shown in the small ganglia of the hypoganglionic segment.(ABSTRACT TRUNCATED AT 250 WORDS)
Neural crest (NC) cells differentiate IN VITRO into neuroblasts, precursors of the enteric nervou... more Neural crest (NC) cells differentiate IN VITRO into neuroblasts, precursors of the enteric nervous system (ENS), when stimulated by specific agents. We developed a study aimed at establishing whether NC-derived neuroblasts can survive and colonise IN VIVO when injected into a recipient mouse gut. The neuroblast precursors of the ENS were obtained from the vagal portion of the neural tubes of 296 CD-1 and GTROSA26 mouse embryos. The embryonic cells of GTROSA26 mice are identifiable through beta-galactosidase activity which allows recognition by blue staining. The host used in this study was the DOM/+ mouse, an animal model for Hirschsprung's disease (aganglionic megacolon). DOM/+ mouse pups (n = 43) received NC-derived cells inoculated into the seromuscular layer of the gut (33/43) or directly into the peritoneal abdominal cavity (10/43). All DOM/+ mice survived the procedure and were sacrificed after 7 or 14 days. Histochemical staining detected implanted cells in all mice. These showed specific myenteric colonisation into the aganglionic and ganglionic gut. The striking result of this study was the specific tropism of the injected NC-derived cells to target sites under the action of unknown chemotactic agents. This experimental procedure might represent a possible treatment option for specific forms of human ENS anomaly such as total intestinal aganglionosis.
Aim of this study was to investigate, for the first time, whether isolated newborn mouse enteric ... more Aim of this study was to investigate, for the first time, whether isolated newborn mouse enteric plexus could induce in vitro differentiation of the vagal neural crest-derived cells into enteric neuroblasts. Fragments of the myenteric plexus were isolated from the small intestine of 6-day-old Swiss mice and were collected and stored in DMEM-F12 medium, then cultured on polymerized human fibronectin layer. The vagal portion of the neural tube, isolated from a 9.5-day-old Swiss mouse embryo, was put in the same chamber slides where the isolated myenteric plexus had been cultured for 3 days. The vagal neural crest-derived cells migrated onto the polymerized human fibronectin layer and formed a crown of cells around the neural tube. After 6 days, the cultures were stopped and studied immunohistochemically for anti-NF160 KD, anti-TH, and RetR5 antibodies to analyse the differentiation stage of the cultured cells. Analysis of results included the comparison of two culture groups: Group 1, used as control, in which vagal neural crest-derived cells were put in DMEM-F12, supplemented only with 10 % of FCS; Group 2, in which vagal neural crest-derived cells were put in the same medium as Group 1, with the addition of myenteric plexus fragments isolated from newborn mice to form the co-culture. The following results were obtained: in Group 1 the neural tubes originated a cell population strongly positive for anti-NF160 and anti-TH Ab, but negative for RetR5 Ab. This positivity was found both in the cells adjacent to the neural tube and in those migrating from it distally. The Group 2 originated cells, which after migration were positive for anti-NF160 and for anti-TH antibodies. In addition, in this culture group, the cells which migrated from the neural tube were positive for anti-RetR5 antibody. The co-culture used in this study induces the differentiation of vagal stem cells into enteric neuroblasts, cells TH+ and RetR5+. These cells, after reaching the embryonic intestine, migrate to colonize the hindgut and form the ENS. Therefore this biotechnology seems a good method to obtain in vitro enteric precursors of ENS.
T lymphocytes arise in the thymus and seed to peripheral lymphoid organs as fully functional cell... more T lymphocytes arise in the thymus and seed to peripheral lymphoid organs as fully functional cells at the time of exit. In humans, the thymus begins to function very early in ontogeny and releases large numbers of T cells before the time of birth. However, the vast majority of developing thymocytes (>95%) die within the thymus as a result of stringent selection processes. Positive selection imposes self-MHC-restriction on thymocytes and dictates the MHC-restricted repertoire of post-thymic T cells. Negative selection results in deletion of autoreactive cells. Both types of selection depend on cell to cell contracts and on the presence of appropriate growth factors which are still largely undetermined. Cell to cell contacts occur between developing thymocytes and cells of the thymic microenvironment (accessory cells), and are mediated by several receptor/ligand interactions which subserve the function of establishing and stabilizing these contacts. Besides MHC-TCR interactions, adhesion molecules are important for thymocyte maturation, selection and activation, and for the export and peripheral homing of mature T cells produced in the thymus. Here we describe a novel integrin involved in thymocyte-thymic epithelial cell interactions.
Background Breast cancer is a major malignancy affecting females worldwide. It is the most common... more Background Breast cancer is a major malignancy affecting females worldwide. It is the most common cause of death from cancer in women. Cell lines are widely used in laboratory research and particularly as in vitro models in cancer research. But we found that the routinely used breast cancer cell lines were mostly derived from Caucasians or African-Americans. There were few standard models to study the pathogenic mechanism at molecular level and cell signaling pathway of breast cancer for Asian patients. It is quite necessary to establish new breast cancer cell lines from xanthoderm to study the pathogenic mechanism and therapeutic methods. Results Three new breast cancer cell lines, designated BC-019, BC-020 and BC-021, were successfully established and characterized from breast invasive ductal carcinoma tissues of three Chinese female patients. These new cell lines growing as adherent monolayer with characteristic epithelial morphology could be maintained continuously in vitro, and...
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Papers by Anna Favre