31 research outputs found
Exceptionally Preserved Cambrian Trilobite Digestive System Revealed in 3D by Synchrotron-Radiation X-Ray Tomographic Microscopy
The Cambrian ‘Orsten’ fauna comprises exceptionally preserved and phosphatised microscopic arthropods. The external morphology of these fossils is well known, but their internal soft-tissue anatomy has remained virtually unknown. Here, we report the first non-biomineralised tissues from a juvenile polymerid trilobite, represented by digestive structures, glands, and connective strands harboured in a hypostome from the Swedish ‘Orsten’ fauna. Synchrotron-radiation X-ray tomographic microscopy enabled three-dimensional internal recordings at sub-micrometre resolution. The specimen provides the first unambiguous evidence for a J-shaped anterior gut and the presence of a crop with a constricted alimentary tract in the Trilobita. Moreover, the gut is Y-shaped in cross section, probably due to a collapsed lumen of that shape, another feature which has not previously been observed in trilobites. The combination of anatomical features suggests that the trilobite hypostome is functionally analogous to the labrum of euarthropods and that it was a sophisticated element closely integrated with the digestive system. This study also briefly addresses the preservational bias of the ‘Orsten’ fauna, particularly the near-absence of polymerid trilobites, and the taphonomy of the soft-tissue-harbouring hypostome
IgG Antibodies against Measles, Rubella, and Varicella Zoster Virus Predict Conversion to Multiple Sclerosis in Clinically Isolated Syndrome
BACKGROUND:Multiple sclerosis (MS) is characterized by a polyspecific B-cell response to neurotropic viruses such as measles, rubella and varicella zoster, with the corresponding antibodies measurable in CSF as the so-called "MRZ reaction" (MRZR). We aimed to evaluate the relevance of MRZR to predict conversion of patients with clinically isolated syndrome (CIS) to MS, and to compare it to oligoclonal bands (OCB) and MRI. METHODOLOGY/PRINCIPAL FINDINGS:MRZR was determined in a prospective study over 2 years including 40 patients that remained CIS over follow-up (CIS-CIS) and 49 patients that developed MS (CIS-RRMS) using ELISA. Using logistic regression, a score (MRZS) balancing the predictive value of the antibody indices included in MRZR was defined (9 points measles, 8 points rubella, 1 point varicella zoster, cutpoint: sum of scores greater 10). MRZR and MRZS were significantly more frequent in CIS-RRMS as compared to CIS-CIS (p=0.04 and p=0.02). MRZS showed the best positive predictive value (PPV) of all parameters investigated (79%, 95%-CI: 54-94%), which could be further increased by combination with MRI (91%, 95%-CI: 59-99%). CONCLUSIONS/SIGNIFICANCE:Our data indicate the relevance of MRZR to predict conversion to MS. It furthermore shows the importance of weighting the different antibody indices included in MRZR and suggest that patients with positive MRZR are candidates for an early begin of immunomodulatory therapy
Targeted antiangiogenic agents in combination with cytotoxic chemotherapy in preclinical and clinical studies in sarcoma
Sarcomas are a heterogeneous group of mesenchymal malignancies. In recent years, studies have demonstrated that inhibition of angiogenic pathways or disruption of established vasculature can attenuate the growth of sarcomas. However, when used as monotherapy in the clinical setting, these targeted antiangiogenic agents have only provided modest survival benefits in some sarcoma subtypes, and have not been efficacious in others. Preclinical and early clinical data suggest that the addition of conventional chemotherapy to antiangiogenic agents may lead to more effective therapies for patients with these tumors. In the current review, the authors summarize the available evidence and possible mechanisms supporting this approach
In vivo relationship of interleukin-2 and soluble IL-2 receptor to blood-brain barrier impairment in patients with active multiple sclerosis
Interleukin (IL)-2 has well-recognized effects on cerebral endothelial cells and, therefore, may mediate disruption of the blood-brain barrier in patients with multiple sclerosis (MS). To evaluate the in vivo relationship of the IL-2 system to blood-brain barrier impairment in MS, levels of IL-2 and soluble IL-2 receptors (sIL-2R) in cerebrospinal fluid (CSF) and serum samples from 50 patients with active MS and 49 controls were correlated with values of the CSF to serum albumin ratio. Intrathecal levels of IL-2 and sIL-2R were significantly higher in MS compared with the control groups and correlated with albumin ratios in MS patients. Intrathecal levels of IL-2 and sIL-2R also correlated with the degree of barrier damage in these patients. It is suggested that intrathecal levels of IL-2 and sIL-2R are related to barrier impairment in MS and may be important in understanding some of the pathological changes of this condition. © 1993 Springer-Verlag.SCOPUS: ar.jinfo:eu-repo/semantics/publishe