104 research outputs found
Form and formation of flares and parabolae based on new observations of the internal shell structure in lytoceratid and perisphinctid ammonoids
The ultrastructure of pristine shells of Jurassic and Cretaceous lytoceratid
and perisphinctid ammonoids indicates that flares and parabolae represent
homologous structures. Both mark an interruption of shell growth. We dismiss
earlier interpretations of parabolae as actual aperture, relics of resorbed
apophyses or superstructure of the musculature associated to a semi-internal
shell. Instead we propose an episodic growth model including several growth
stops at the aperture during the formation of a frill-like aperture for
parabolae and flares. Such an aperture is composed of the outer prismatic
layer, the nacreous layer and an apertural prismatic coating. Here, we
observed the apertural prismatic coating for the first time as an integral
part of flares and parabolae. The apertural prismatic coating covers only the
inner surface of the frill and was secreted by a permanent mantle cover
indicating a prolonged period without the production of new shell material.
Parabolae differ from flares by their general shape and the presence of
ventro-lateral parabolic notches and nodes. The notches were formed by folding
of the frill and had the potential to form semi-open spines. The corresponding
parabolic nodes are caused by an outward swelling of the shell-secreting
mantle tissue producing new shell material at the position of the folding. New
shell material that belongs to the conch tube is attached to the base of
flares and parabolae after withdrawal of the mantle edge representing the
continuation of shell growth. Usually, the frilled aperture associated with
flares and parabolae were removed during lifetime. This study reports on
flares in Argonauticeras for the first time. In this genus they are typically
associated with varices
The Isolated Orbital Floor Fracture from a Transconjunctival or Subciliary Perspective-A Standardized Anthropometric Evaluation
Background: The influence of orbital fractures and their repair on the rate of deformities of the lower eyelid is an ongoing source of discussion in the literature. Most of the present studies include isolated blow-out as well as combined orbital fractures. Material and Methods: We present a retrospective evaluation of a series of 100 patients after isolated blow-out fracture repair using reference anthropometric data on standardized photographs. Analysis included eye fissure width and height, lid sulcus height, upper lid height, upper and lower iris coverage, position of cornea to palpebra inferior, canthal tilt, scleral show, ectropion and entropion. It was clearly distinguished between operated and contralateral eyelid, whether a transconjunctival or a subciliary approach was performed and amount of fracture. Our main interests were changes of the aforementioned parameters with regards to eyelid deformities. Results: Surgery per se did not significantly influence eyelid deformities. However, the surgical approach selected significantly affected eye fissure index, lower iris coverage and rate of scleral show, indicating retraction of the lower eyelid. Conclusions: The standardized measurements described here are accurate and objective to evaluate postoperative results. The subciliary approach included the highest risk of lower lid retraction as compared to transconjunctival approaches
Transfusion of Target Antigens to Pre-Immunized Recipients:A New Mechanism in Transfusion-Related Acute Lung Injury
Transfusion-related lung injury (TRALI) is a serious side effect of blood transfusion. Exclusion of antibody carriers from the donor pool has significantly decreased the number of cases, but TRALI remains the leading cause of transfusion-related morbidity and mortality in industrialized countries. Here, we show that proteins released from donor cells during processing of blood components are capable of inducing a new type of reverse TRALI when transfused to preimmunized recipients. First, we show that soluble neutrophil surface protein CD177 in complex with proteinase 3 (sCD177/PR3) is not only present in human plasma but also in packed red blood cell (PRBC) supernatant. Filtration or storage enhances the concentration of sCD177/PR3 in PRBCs. Second, we show that sCD177/PR3 specifically binds to PECAM-1 on stimulated (but not on unstimulated) endothelial cells (ECs). Third, we provide evidence that the sCD177/PR3/PECAM-1 complex is functional. In the presence of monoclonal or human antibodies against CD177 or PR3, ECs produce reactive oxygen species and become apoptotic. Albumin flux through an EC monolayer increases significantly whenever antibodies and the cognate antigens are present. Finally, we describe a clinical case in which anti-CD177 present in a transfusion recipient precipitated TRALI after the transfusion of CD177-positive, but not CD177-negative, PRBCs. In conclusion, we introduce a new TRALI mechanism based on the specific binding of transfused, soluble antigens to activated ECs in preimmunized recipients. We suggest that further studies and clinical work-up of TRALI should also include antibody investigation of the recipient
a protocol for developing a patient-reported outcome measurement instrument
Introduction: There is no consensus about what constitutes the most
appropriate patient-reported outcome measurement (PROM) instrument for
measuring physical function in patients with rheumatic hand conditions.
Existing instruments lack psychometric testing and vary in feasibility and
their psychometric qualities. We aim to develop a PROM instrument to assess
hand-related physical function in rheumatic hand conditions. Methods and
analysis: We will perform a systematic search to identify existing PROMs to
rheumatic hand conditions, and select items relevant for hand-related physical
function as well as those items from the Patient Reported Outcomes Measurement
Information System (PROMIS) Physical Function (PF) item bank that are relevant
to patients with rheumatic hand conditions. Selection will be based on
consensus among reviewers. Content validity of selected items will be
established through the use of focus groups. If patients deem necessary, we
will develop new items based on the patients' input. We will examine whether
it is valid to score all selected and developed items on the same scale as the
original items from the PROMIS PF item bank. Our analyses will follow the
methods used for calibrating the original PROMIS PF item bank in US samples,
which were largely based on the general PROMIS approach. Ethics and
dissemination: This study will be carried out in accordance with the Helsinki
Declaration. Ethics approvals will be obtained where necessary, and signed
informed consent will be obtained from all participants. We aim to disseminate
the results of the study through publication in international peer-reviewed
journals and at international conferences
Hand-related physical function in rheumatic hand conditions:a protocol for developing a patient-reported outcome measurement instrument
Introduction: There is no consensus about what constitutes the most appropriate patient-reported outcome measurement (PROM) instrument for measuring physical function in patients with rheumatic hand conditions. Existing instruments lack psychometric testing and vary in feasibility and their psychometric qualities. We aim to develop a PROM instrument to assess hand-related physical function in rheumatic hand conditions.
Methods and analysis: We will perform a systematic search to identify existing PROMs to rheumatic hand conditions, and select items relevant for hand-related physical function as well as those items from the Patient Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF) item bank that are relevant to patients with rheumatic hand conditions. Selection will be based on consensus among reviewers. Content validity of selected items will be established through the use of focus groups. If patients deem necessary, we will develop new items based on the patients' input. We will examine whether it is valid to score all selected and developed items on the same scale as the original items from the PROMIS PF item bank. Our analyses will follow the methods used for calibrating the original PROMIS PF item bank in US samples, which were largely based on the general PROMIS approach.
Ethics and dissemination: This study will be carried out in accordance with the Helsinki Declaration. Ethics approvals will be obtained where necessary, and signed informed consent will be obtained from all participants. We aim to disseminate the results of the study through publication in international peer-reviewed journals and at international conferences
Understanding tumor localization in multiparametric MRI of the prostate—effectiveness of 3D printed models
IntroductionUnderstanding tumor localization in multiparametric MRI (mpMRI) of the prostate is challenging for urologists but of great importance in mpMRI-fused prostate biopsy or radical prostatectomy. The aim was to evaluate the effectiveness of 3D printed models of the prostate to help urologists to locate tumors.Methods and Participants20 urologists from University Medical Center Mainz (Germany) were asked to plot the location of a cancer suspicious lesion (PI-RADS ≥ 4) on a total of 30 mpMRI on a prostate sector diagram. The following 3 groups (as matched triplets) were divided into: mpMRI only, mpMRI with radiological report and mpMRI with 3D printed model (scaled 1:1). Statistical analysis was performed using one-way and two-way ANOVA (with bonferroni post-test).ResultsOverall, localization of the suspicious lesion was superior with the radiological report (median of max. 10 [IQR]: MRI 2 [IQR 1;5], MRI + report: 8 [6.3;9], MRI + 3D model 3 [1.3;5.8]; p < 0.001). Residents with <1 year of experience had a significantly higher detection rate using a 3D printed model [5 (5;5.8)] compared to mpMRI alone [1.5 (1;3.5)] (p < 0.05). Regarding the estimation of index lesion extension, the 3D model showed a significant benefit (mean percentage difference [95% CI]: MRI alone 234% [17.1;451.5], MRI + report 114% [78.5;149.6], MRI + 3D model 17% [−7.4;41.3] (p < 0.01).ConclusionUrologists still need the written radiological report for a sufficient understanding of tumor localization. The effectiveness of the 3D printed model regarding tumor localization is particularly evident in young residents (<1 year) and leads to a better overall assessment of the tumor extension
Magyar Geofizika 1988
Introduction
Bipolar disorder (BD) is a chronic psychiatric disease which can take most different and unpredictable courses. It is accompanied by unspecific brainstructural changes and cognitive decline. The neurobiological underpinnings of these processes are still unclear. Emerging evidence suggests that tryptophan catabolites (TRYCATs), which involve all metabolites of tryptophan towards the kynurenine (KYN) branch, are involved in the etiology as well as in the course of BD. They are proposed to be mediators of immune-inflammation and neurodegeneration. In this study we measured the levels of KYN and its main catabolites consisting of the neurotoxic hydroxykynurenine (3-HK), the more neuroprotective kynurenic acid (KYNA) and anthranilic acid (AA) and evaluated the ratios between end-products and substrates as proxies for the specific enzymatic activity (3-HK/KYN, KYNA/KYN, AA/KYN) as well as 3-HK/KYNA as a proxy for neurotoxic vs. neuroprotective end-product relation in individuals with BD compared to healthy controls (HC).
Methods
We took peripheral TRYCAT blood levels of 143 euthymic to mild depressive BD patients and 101 HC. For statistical analyses MANCOVA's controlled for age, sex, body mass index, cardiovascular disease and smoking were performed.
Results
The levels of KYNA (F=5,579; p<.05) were reduced in BD compared to HC. The enzymatic activity of the kynurenine-3-monooxygenase (KMO) reflected by the 3-HK/KYN ratio was increased in BD individuals compared to HC (F=5,394; p<.05). Additionally the ratio of 3-HK/KYNA was increased in individuals with BD compared to healthy controls (F=11,357; p<.01).
Discussion
In conclusion our findings subserve the concept of KYN -pathway alterations in the pathophysiology of BD. We present evidence of increased breakdown towards the neurotoxic branch in KYN metabolism even in a euthymic to mild depressive state in BD. From literature we know that depression and mania are accompanied by inflammatory states which should be capable to produce an even greater imbalance due to activation of key enzymes in the neurotoxic direction of KYN -conversion. These processes could finally be involved in the development of unspecific brain structural changes and cognitive deficits which are prevalent in BD. Further research should focus on state dependent changes in TRYCATs and its relation to cognition, brain structure and staging parameters
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