[Case report: Vasa previa diagnosis and management. How to prevent Benckiser's hemorrhage?]. / Cas clinique : diagnostic et prise en charge d'un vasa praevia. Comment prévenir l'hémorragie de Benckiser ?

Benckiser's haemorrhage is a serious obstetrical complication, following a vasa previa rupture. Incidence of vasa previa is estimated between 1/1150 and 1/5000 pregnancies. This case report illustrates the consequences of a suspected vasa previa rupture. There is no French recommendation of how to treat vasa previa. Different methods of prevention are described and examined thanks to a literature review.

[Pediatric outcome after selective feticide for 30 complicated monochorionic twin pregnancies]. / Suivi pédiatrique de 30 grossesses gémellaires monochoriales consécutives traitées par fœticide sélectif.

OBJECTIVES: To describe perinatal and pediatric outcome after selective feticide for complicated monochorionic twin pregnancy. PATIENTS AND METHODS: We reviewed all consecutive cases of umbilical cord occlusion performed for complicated monochorionic twin pregnancy over a 16-year period. Pediatric follow-up was based on medical records and updated by phone calls to the parents. RESULTS: Thirty procedures were performed. Indications were: twin-to-twin transfusion syndrome (TTTS) progressing despite serial amniodrainage (n=12) ; twin reversed arterial perfusion (n=9) ; selective growth restriction (n=5) ; severe discordant structural anomalies (n=4). Mean gestational age at procedure was 21.8±3.1gestational weeks (GW) and 31.8±4.8 GW at birth. Overall survival rate was 87%, i.e. 83%, 100%, 60% and 100% for each indication, respectively. Mean pediatric follow-up was 5years (range: 6months to 15years). Medical charts and parents declared normal development in 88% of surviving children, i.e. 67%, 100%, 100%, and 100% for each indication. Cross-comparison between the four groups revealed that in the TTTS group, gestational age at procedure was more advanced (P=0.01) while delivery was slightly earlier (P=0.1), and pediatric development was poorer (P=0.02). DISCUSSION AND CONCLUSION: Pediatric outcome after selective feticide appeared to be poorer for TTTS progressing despite serial amniodrainage than for other indications.

[Uterine lipoma: A case report probably due to a surgical traumatism]. / Lipome utérin : à propos d'un cas possiblement lié à un traumatisme chirurgical.

Uterine lipomas are uncommon. Several histology hypotheses are described. Ultrasound is firstly performed but diagnosis is sometimes difficult. Magnetic resonance imaging is more specific and helpful to make a differential diagnosis with a dermoid ovarian cyst. Despite those imaging exams we detail a case of a patient where a laparoscopic hysterectomy with bilateral salpingo-oophorectomy and preliminary adhesiolysis has been necessary to establish diagnosis. Among her medical history some previous abdominal surgeries could be the cause of this lesion.

[Importance of bile acids for intra-hepatic cholestasis of pregnancy]. / Intérêt des acides biliaires dans la cholestase gravidique.

Intrahepatic cholestasis during pregnancy is a risk factor for prematurity, respiratory distress, fetal death in utero and exposure to meconium stained liquor. Treatment is based on ursodeoxycholic acid, which allows the pregnancy to continue until term. There is no consensus for labor induction criteria or for extraction of the fetus. We report a series of 10 patients who presented cholestasis during pregnancy and for whom we monitored the bile acid levels. These assays provided the means of confirming the diagnosis in patients suffering from pruritus. The threshold of 40 micromoles/L could be a way of defining a group at risk of complications. Proper management for monitoring this pathology has not yet been properly established, but assay of the bile acids is an important element.

Communication skills training in oncology: it works!

While the previous chapter by L. Fallowfield and V. Jenkins focuses on different communication skills training (CST) concepts currently being utilized, this chapter reviews and comments the scientific evidence of the impact of CST on improving communication skills. The aim of this chapter is not to provide a complete review of the evidence-this has already been done in systematic reviews-but to discuss the scientific evidence and reflect on the available results and relevant topics for further investigations.

Identification of tumor-infiltrating macrophages as the killers of tumor cells after immunization in a rat model system.

Immunization can prevent tumor growth, but the effector cells directly responsible for tumor cell killing in immunized hosts remain undetermined. The present study compares tumor grafts that progress in naive syngeneic rats with the same grafts that completely regress in hosts preimmunized with an immunogenic cell variant. The progressive tumors contain only a few macrophages that remain at the periphery of the tumor without direct contact with the cancer cells. These macrophages do not kill tumor cells in vitro. In contrast, tumors grafted in immunized hosts and examined at the beginning of tumor regression show a dramatic infiltration with mature macrophages, many of them in direct contact with the cancer cells. These macrophages are strongly cytotoxic for the tumor cells in vitro. In contrast to macrophages, tumor-associated lymphocytes are not directly cytotoxic to the tumor cells, even when obtained from tumor-immune rats. However, CD4(+) and CD8(+) T cells prepared from the regressing tumors induce tumoricidal activity in splenic macrophages from normal or tumor-bearing rats and in macrophages that infiltrate progressive tumors. These results strongly suggest that the main tumoricidal effector cells in preimmunized rats are macrophages that have been activated by adjacent tumor-immune lymphocytes.

Role of tumor cell apoptosis in tumor antigen migration to the draining lymph nodes.

Establishment of an immune response against cancer may depend on the capacity of dendritic cells to transfer tumor Ags into T cell-rich areas. To check this possibility, we used a colon cancer cell variant that yields tumors undergoing complete T cell-dependent rejection when injected into syngeneic rats. We previously demonstrated that immunogenicity of these tumors depended on the early apoptosis of a part of these tumor cells. In this paper we show that fluorescent tumor cell proteins are released from FITC-labeled tumor cells and undergo engulfment by tumor-infiltrating monocytes without a phenotype of mature dendritic cells or macrophages. Fluorescence-labeled mononuclear cells with a phenotype of MHC class II+ dendritic cells are also found in the T cell areas of the draining lymph nodes. Interestingly, no fluorescent cell can be found in lymph nodes after a s.c. injection of Bcl2-transfected apoptosis-resistant tumor cells that yielded progressive tumors. Proliferation of tumor-immune T lymphocytes was induced by dendritic cells isolated from the draining lymph nodes recovered after a s.c. injection of apoptosis-sensitive, but not apoptosis-resistant, tumor cells. These results show that tumor cell apoptosis releases proteins that are engulfed by inflammatory cells in the tumor, then transported to lymph node T cell areas where they can induce a specific immune response leading to tumor rejection.

FAS(CD95) ligand expression by tumor cell variants can be unrelated to their capacity to induce tolerance or immune rejection.

According to the results of in vitro experiments, Fas(CD95) ligand expression by cancer cells might induce apoptosis of activated T cells and contribute to immune tolerance. However, Fas ligand expression had never been explored in vivo in tumor cell models yielding either immune response or tolerance. In the present study, we analyzed the expression and function of Fas ligand in 2 clones of tumor cells originating from the same rat colon carcinoma. REGb cells were immunogenic and yielded tumors that regressed in immunecompetent syngeneic hosts, whereas PROb cells induced active tolerance and yielded progressive tumors. Fas ligand was expressed on the plasma membrane of both REGb and PROb cells, and its cDNA sequencing showed no mutation. However, neither REGb nor PROb cells induced apoptosis of co-cultured Fas-sensitive target cells. Our results show that surface expression of Fas ligand by tumor cells does not always induce killing of adjoining Fas-sensitive cells and that tumor cells may induce a protective immune response or an active tolerance independently of Fas ligand expression.

The development of murine cerebral malaria does not require nitric oxide production.

Nitric oxide (NO) production has been suggested to be required for the development of cerebral malaria. However, the importance of this molecule for the appearance of this pathology is debated. To assess whether murine cerebral malaria is NO dependent, we investigated the course of blood-stage Plasmodium berghei ANKA (PbA) infections in inducible nitric oxide synthase (iNOS)-deficient mice. Parasitaemia, haematological alterations, survival and development of cerebral malaria were not affected by the lack of iNOS. To exclude a role of NO produced by other NOS, controls included NO suppression by oral administration of aminoguanidine (AG), a NOS inhibitor. As in iNOS-deficient mice, no difference in the parasitaemia course, survival and haematological values was observed after AG treatment. Our results indicate that NO production is not a crucial factor for the development of murine cerebral malaria.

Parasite killing in murine malaria does not require nitric oxide production.

Nitric oxide (NO) production has been suggested to play a role as effector molecule in the control of the malarial infections. However, the roles of this molecule are debated. To assess whether blood-stage parasite killing is NO dependent, we investigated the course of blood-stage Plasmodium chabaudi chabaudi (Pcc) infections in inducible nictric oxide synthase (iNOS)-deficient mice. Parasitaemia, haematological alterations, and survival were not affected by the lack of iNOS. To exclude a role of NO produced by other NOS, controls included NO suppression by oral administration of aminoguanidine (AG), a NOS inhibitor. As in iNOS-deficient mice, no difference in the parasitaemia course, survival and haematological values was observed after AG treatment. Our results indicate that NO production is not required for protection against malaria in our murine experimental model. However, C57BL/6 mice treated with AG lost their resistance to Pcc infections, suggesting that the requirement for NO production for parasite killing in murine blood-stage malaria might be strain dependent.

Role of ICAM-1 (CD54) in the development of murine cerebral malaria.

In susceptible mouse strains, infection of mice with Plasmodium berghei ANKA (PbA) results in a lethal complication, cerebral malaria. Cerebral malaria is due to the immune response induced by the parasite, which results in an increased production of TNF, known to increase the expression of adhesion molecules on the endothelia. To investigate the role of the adhesion molecule ICAM-1 (CD54), we infected wild-type (+/+) and ICAM-1-deficient (-/-) mice with PbA. While +/+ mice died 6-8 days after infection, -/- mice survived > 15 days. Parasitaemia was similar in +/+ and -/- mice. Serum TNF concentration was increased by the infection and was significantly higher in infected +/+ than in -/- mice. However, TNF mRNA levels in spleen, lungs, and brain were elevated in both infected +/+ and -/- mice. For IFN-gamma, serum levels were similar in both groups. A breakdown of the blood-brain barrier was evident in infected +/+ mice only. Interestingly, thrombocytopenia was profound in infected +/+, but practically absent in -/- mice. Moreover, macrophage sequestration was evident in brain venules and lung capillaries of +/+ mice and was significantly less important in the alveolar capillaries of infected -/- mice. In contrast, neutrophil sequestration in the lung was similar in both +/+ and -/- mice. Sequestration of parasitized red blood cells was significantly greater in the alveolar capillaries from +/+ than -/- mice. These results indicate that while the immune response is similar in both +/+ and ICAM-1(-/-) mice, the absence of mortality in ICAM(-/-) mice correlates with a decrease of macrophage and parasitized RBC trapping and a less severe thrombocytopenia.

Heat shock protein 27 enhances the tumorigenicity of immunogenic rat colon carcinoma cell clones.

The REG and PRO cell clones were obtained from a colon adenocarcinoma induced in a BDIX rat by 1,2-dimethylhydrazine. When injected s.c. into syngeneic hosts, REG cells induce tumors that regress in less than 3 weeks, whereas PRO cells, like parental cells, induce progressive tumors. Here, we show that compared to PRO cells, REG cells are more sensitive to cell death induced by anticancer drugs. The small heat shock protein (HSP) 27 is not expressed or inducible in REG clones, whereas it is abundantly expressed and inducible by heat shock in PRO clones. The expression of HSP27 in REG cells increases their resistance to apoptosis in vitro and dramatically enhances their tumorigenicity when injected s.c. into syngeneic rats. HSP27 expression in REG cells both increases tumor size and delays tumor regression. This increased tumorigenicity is associated with a substantial decrease of in vivo tumor cell apoptosis. We conclude that HSP27 expression in malignant cells increases their tumorigenicity in syngeneic animals. In combination with the role of HSP27 in tumor cell resistance to cytotoxic agents, its contribution to tumorigenicity makes this protein a potential target for antitumoral therapy.

Immunization of mice with phosphatidylcholine drastically reduces the parasitaemia of subsequent Plasmodium chabaudi chabaudi blood-stage infections.

It has been suggested that phospholipids and antibodies directed against phospholipids are important in the pathology of malaria. We have investigated the influence of immunizations with phospholipids on the course of subsequent blood-stage Plasmodium chabaudi chabaudi infections in ICR inbred mice. We observed a significant reduction in the parasitaemia following immunization with phosphatidylcholine (PC), but not with phosphatidylethanolamine (PE) immunization. At the peak of the infection, PC-immunized mice displayed a T-helper 2 (Th2)-type cytokine production pattern, whereas PE-immunized or non-treated controls displayed a cytokine production pattern of the T-helper 1 (Th1) type. Serum immunoglobulin transfer from PC-immunized mice protected naive mice in a similar fashion to PC-immunization, demonstrating that the observed reduction of parasitaemia was caused by the presence of PC-specific antibodies.

Bcl-2-mediated inhibition of apoptosis prevents immunogenicity and restores tumorigenicity of spontaneously regressive tumors.

Tumor cell clones from a rat colon carcinoma differ in their tumorigenicity and immunogenicity. The PRO clones give rise to progressive tumors, whereas the REG clones yield tumors that regress in a few weeks through a specific immune response. REG cells were more sensitive than PRO cells to apoptosis triggered by serum withdrawal in vitro. Furthermore, a fraction of REG cells, but no PRO cells, underwent apoptosis in the hours following injection into syngeneic rats. To further analyze the role of apoptosis, we overexpressed the antiapoptotic protein Bcl-2 in REG cells. Unlike parental or fake-transfected REG cells, Bcl-2-overexpressing REG cells resisted serum withdrawal-induced apoptosis, did not undergo apoptosis at 48 h postinjection into naive syngeneic rats, and gave rise to progressive, metastatic, and lethal tumors. Interestingly, REG-bcl2 cells were rejected by syngeneic hosts that had been preimmunized by an injection of parental REG cells, indicating that Bcl-2 overexpression did not alter tumor cell sensitivity to the effector cells of the immune response. Taken together, these observations indicate that tumor cell apoptosis may contribute to immunogenicity.

Sequence and diversity of T-cell receptor alpha V, J, and C genes of the owl monkey Aotus nancymaae.

We cloned and sequenced TcR alpha chain cDNA of three healthy Aotus nancymaae monkeys. Fifteen different TRAJ segments and 9 different TRAV genes were identified in the 29 rearrangements analyzed. As expected from the greater phylogenetic distance, A. nancymaae TRA gene sequences diverged more from the human sequences than those of the chimpanzee or the rhesus macaque. However, no Aotus TRAJ segment or TRAV gene was found which lacked a human counterpart. These counterparts were AJ02, AJ05, AJ09, AJ15, AJ22, AJ23, AJ28, AJ30, AJ32, AJ34, AJ37, AJ40, AJ42, AJ45, AJ52 and AV2S1, AV2S3, AV3S1, AV8S1, AV12S1, AV15S1, ADV21S1/DV5, AV22S1S and AV23S1, respectively. In most cases the identity of amino acid sequences between corresponding Aotus and human genes was greater than 80%. This marked conservation of TRA gene sequences indicates a close structural relationship of Aotus and human TcR and demonstrates that the TcR repertoire in primates is remarkably stable. The results support the concept of using Aotus monkeys, which are susceptible to infection with the human malaria parasite Plasmodium falciparum, as an animal model for the evaluation of molecularly defined malaria vaccine candidates.

Cancer cell sensitization to fas-mediated apoptosis by sodium butyrate.

Cancer cells often resist Fas-mediated apoptosis even when the Fas receptor is expressed at the cell surface. We show here that human and rat colon cancer cells undergo massive apoptosis when they are exposed to soluble Fas ligand in the presence of sodium butyrate, an agent that induces by itself only a low rate of apoptosis. Sodium butyrate potentiates Fas-dependent apoptosis in seven out of eight colon cancer cell lines. Sodium butyrate does not increase Fas receptor cell surface expression and does not modify cell levels of Bcl-2, Bcl-xL, Bcl-xS and Bax. Sodium butyrate also induces tumor cell sensitization to the apoptotic effect of the combination of TNF-alpha and IFN-gamma, but it does not modify the level of the FADD/Mort1 adaptator molecule, at the connection between Fas- and TNF-dependent apoptosis pathways. Because the clinical toxicity of butyrate is low, its ability to enhance Fas-signal delivery in cancer cells could be of therapeutic interest.

Malaria toxins from P. chabaudi chabaudi AS and P. berghei ANKA cause dyserythropoiesis in C57BL/6 mice.

The lack of correlation between parasitaemia and anaemia in severe malaria indicates that factors in addition to schizont rupture or erythrophagocytosis contribute to anaemia. We asked whether malaria toxin (MT) from Plasmodium berghei or P. chabaudi might impair erythropoiesis. Daily intraperitoneal injection of MT into C57BL/6 mice induced a transient reduction of RBC values by 25-30% after about 2 weeks, followed by increased haematopoiesis in the spleen as compared to mice receiving uninfected RBC preparations. There was a 3 (P. berghei) to 8-fold (P. chabaudi) increase of total proliferative activity in the spleen. Flow cytometric analyses showed that this was accompanied by some differentiation of TER-119 positive erythroid cells and of Gr-1 positive myeloid cells. Erythroid and myeloid progenitor cell-derived colony assays confirmed these results and revealed an increase in the number of CFU-E (< or = 200-fold), BFU-E (< or = 10-fold) and CFU-GM (< or = 20-fold) in the spleen of MT treated mice, as compared to controls.

Malaria toxins: effects on murine spleen and bone marrow cell proliferation and cytokine production in vitro.

The ability of deproteinated malaria exoantigens from Plasmodium falciparum (Pf-MT) and P. berghei ANKA (PbA-MT) to activate murine haematopoietic cells was analysed in vitro. Malaria toxins (MT) of both plasmodium species induced cell proliferation and the production of IFN-gamma in overnight and long-term (5 days) spleen and bone marrow cultures and a reduction of the number of TNF-alpha spot forming cells (SFC). When added to cells of malaria-experienced animals, MT decreased the number of IL-4 SPC and increased the number of IL-5 SPC. However, the same proliferative and IFN-gamma induction properties as in naive cells were observed. Simultaneous addition of IL-2 and PbA-MT to spleen cells inhibited the proliferation but increased the IFN-gamma production usually induced by IL-2. Flow cytometric analysis revealed that the addition of MT triggered an expansion of CD3+ and GR1+ cell populations. Our results suggest that malaria toxins of different species can induce an immediate and strong proliferation and a TH1-type cytokine release by murine cells, independently of previous in vivo priming.