Pregnancy associated plasma protein-A (PAPP-A) is not a marker of the vulnerable atherosclerotic plaque.

OBJECTIVE: To investigate if pregnancy associated plasma protein-A (PAPP-A) was present in the vulnerable plaque, and if not, to find alternative hypothesis for the release of PAPP-A. DESIGN AND METHODS: Vulnerable plaques and control tissues were examined by immunohistochemistry. Volunteers and patients with non-atherosclerotic disease were examined for release of PAPP-A during ischemia and medical treatment. Non-atherosclerotic tissue samples were examined after incubation with heparins. RESULTS: We were not able to detect PAPP-A in vulnerable plaques. Patients and volunteers experiencing ischemic events without atherosclerotic lesions only had elevated PAPP-A when treated with heparin. When tissue from normal artery wall was incubated with heparin, PAPP-A was eluted. This was not the case for non-arterial tissue samples. CONCLUSION: Elevation of PAPP-A in patients with acute coronary syndromes seems to be caused by heparin induced release of PAPP-A from the arterial wall and not due to excretion from vulnerable plaques.

Success and spontaneous pregnancy rates following systemic methotrexate versus laparoscopic surgery for tubal pregnancies: a randomized trial.

OBJECTIVE: To determine which treatment should be offered to women with a non-ruptured tubal pregnancy: a single dose of methotrexate (MTX) or laparoscopic surgery. DESIGN: Prospective, randomized, open multicenter study. SETTING: Seven Danish departments of obstetrics and gynecology. SAMPLE: A total of 106 women diagnosed with ectopic pregnancy (EP). METHODS: Between March 1997 and September 2000, 1,265 women were diagnosed with EP, 395 (31%) were eligible, 109 (9%) were randomized of whom 106 had an EP. The study was originally powered to a sample size of 422 patients. The women were randomized to either medical (MTX; 53) or surgical (laparoscopic salpingotomy; 53) treatment. Follow-up by questionnaire and through national patient databases for a maximum of 10 years. MAIN OUTCOME MEASURES: Uneventful decline of plasma-human chorionic gonadotropin to less than 5 IU/L, rates of spontaneous, subsequent intrauterine, and recurrent ectopic pregnancies. RESULTS: The success rates were 74% following MTX treatment and 87% after surgery (n.s.); the subsequent spontaneous intrauterine pregnancy rate was 73% after MTX and 62% after surgery; and the EP rate was 9.6% after MTX and 17.3% following surgery (n.s.). CONCLUSIONS: In women with an EP, who are hemodynamically stable and wishing to preserve their fertility, medical treatment with single dose MTX tends to be equal to treatment with laparoscopic surgery regarding success rate, complications, and subsequent fertility. Although the two treatment modalities seemed to be similar in outcome, it is crucial that the diagnosis is based on a high-quality ultrasonographic evaluation, as two patients had intrauterine pregnancies despite fulfilling the diagnostic algorithm for EP.

Multimeric and trimeric subunit SP-D are interconvertible structures with distinct ligand interaction.

Surfactant protein-D (SP-D) is a calcium dependent lectin in the innate immune system that facilitates clearance of microbes. The protein is associated with mucosal surfaces, and also found in bronchoalveolar lavage, serum and amniotic fluid. Human SP-D includes trimeric subunits and multimeric assemblies of trimeric subunits, which are stabilized by N-terminal interchain disulfide crosslinks. An N-terminal structural polymorphism (Met11Thr) and associated O-glycosylation are previously shown accompanied by incomplete multimerization and with a relative low proportion of multimeric Thr11 SP-D compared to Met11 SP-D. Multimerization has proven important for enhancement of microbial phagocytosis. In the present study defined multimeric forms of Met11Thr SP-D were isolated from human amniotic fluid. Implementation of ManNAc-affinity chromatography allowed high recovery of natural trimeric SP-D subunits. However, affinity chromatography increased the relative proportion of multimers at the expense of natural trimeric subunits. Multimeric SP-D partially disassembled to form trimeric subunits. The resulting distribution of structural forms was independent of the Met11Thr genotype. Trimeric and multimeric SP-D appeared with distinct patterns of disulphide crosslinking, which partly changed according to interconversion between the structural forms. Solid phase assays demonstrated that trimeric SP-D subunits showed greater binding to LPS and PGN, but lower binding to mannan and LTA, than SP-D multimers. Trimeric SP-D subunits also showed greater binding to endogenous lipoproteins: LDL, oxLDL, and HDL, than multimeric SP-D. In conclusion, purified trimeric and multimeric SP-D represent separate and only partly interconvertible molecular populations with distinct biochemical properties.

Expression and tissue localization of collectin placenta 1 (CL-P1, SRCL) in human tissues.

Collectin placenta-1 (CL-P1), also known as scavenger receptor with C-type lectin (SRCL), is a type II membrane glycoprotein that shares structural features with both collectins and type A scavenger receptors. CL-P1 was originally cloned from the placenta and found to be associated with endothelial cells. It binds via its lectin domain to desialyated Lewis X containing glycoproteins and it is able to facilitate internalization of bound ligands. Via positively charged residues in the collagen-like region it binds to negatively charged components of microbial membranes. It has previously been proposed that CL-P1 plays a role in the host defense system and in the clearance of glycoproteins from the blood. With the aims of determining the detailed tissue expression of human CL-P1 we expressed CL-P1 recombinantly in both E. coli and CHO cells, and raised monoclonal antibodies against human CL-P1. Three monoclonal antibodies were characterized and used in immunohistochemical analyses of a panel of cryo- and formalin-fixed sections. We find that CL-P1 mainly associates with cytotrophoblasts and syncytiotrophoblasts of the placenta, alveolar macrophages and to a less degree with macrophage-like and stromal cells of the tonsils. By real-time RT-PCR we verified that the placenta is also the main organ of CL-P1 synthesis. The only source of endothelial cells whereto CL-P1 associates are umbilical cord vein endothelial cells (human umbilical vein endothelial cells, HUVEC). In vitro cultured HUVECs express both the CL-P1 mRNA and show anti-CL-P1 immunoreactivity but CL-P1 locates mainly to the cytosol and not to the membrane of these cells. We conclude that CL-P1 is not a common membrane protein on endothelial cells found in normal tissues under steady state conditions.

Activin B mediated induction of Pdx1 in human embryonic stem cell derived embryoid bodies.

Human embryonic stem cells (hESCs) have the potential to provide alternative sources for pancreatic islet grafts. In the present study we have investigated the influence of Activin A and Activin B on the expression of the pancreas marker gene Pdx1 in hESCs differentiated as embryoid bodies (EBs). We report here that Activin B in a dose depend manner markedly up-regulates Pdx1 expression as compared to Activin A and untreated cultures. Pdx1(+) cells co-express FOXA2 but lacks, however, co-expression with nkx6.1, a marker combination that in the present study is shown precisely to identify embryonic and fetal pancreas anlage in humans. Pdx1(+) cells are found in cell clusters also expressing Serpina1 and FABP1, suggesting activation of intestinal/liver developmental programs. Moreover, Activin B up-regulates Sonic Hedgehog (Shh) and its target Gli1, which during normal development is suppressed in the pancreatic anlage. In conclusion, Activin B is a potent inducer of Pdx1 as well as Shh in differentiating hESCs. The data suggest that additional suppression of Shh signaling may be required to allow for proper specification of pancreatic cell lineages in hESCs.