An autonomous lab on a chip for space flight calibration of gravity-induced transcellular calcium polarization in single-cell fern spores.

This report describes the development of lab-on-a-chip device designed to measure changes in cellular ion gradients that are induced by changes in gravitational (g) forces. The bioCD presented here detects differential calcium ion concentrations outside of individual cells. The device includes sufficient replicates for statistical analysis of the gradients around multiple single cells and around control wells that are empty or include dead cells. In the data presented, the degree of the cellular response correlates with the magnitude of the g-force applied via rotation of the bioCD. The experiments recorded the longest continuous observation of a cellular response to hypergravity made to date, and they demonstrate the potential utility of this device for assaying the threshold of cells' g-force responses in spaceflight conditions.

Clinical characteristics and course of plantar vein thrombosis: a series of 22 cases.

OBJECTIVES: To evaluate the clinical presentation and disease course of symptomatic plantar vein thrombosis. PATIENTS AND METHODS: Patients with a first diagnosis of symptomatic plantar vein thrombosis at our institution were retrospectively identified from a prospectively maintained database. All patients underwent complete venous compression sonography extended to the plantar veins because of local symptoms at the sole of the foot. Clinical characteristics were obtained from the medical records. RESULTS: Between 2005 and 2013, 22 patients were diagnosed with a first episode of plantar vein thrombosis (64% women, mean age at diagnosis 58.2 years, range 32-79 years). All patients reported moderate to heavy pain of the sole of the foot. The lateral plantar veins (96%) were more frequently affected than the medial plantar veins (41%) and extension into the deep calf veins was common (27%). Half of the episodes were idiopathic, with subsequent diagnosis of occult malignancy in two of these patients. In seven patients (32%), plantar vein thrombosis occurred in association to physical strain to the foot. All patients were treated with anticoagulation. Symptomatic pulmonary embolism was not observed and during a mean follow up of 21 months, the post-thrombotic syndrome did not occur. However, recurrences were common (27%) and frequently again affected the plantar veins. CONCLUSION: Plantar vein thrombosis should be considered as an important differential diagnosis of acute foot pain.

Lack of association between venous hemodynamics, venous morphology and the postthrombotic syndrome after upper extremity deep venous thrombosis.

OBJECTIVES: To explore the association of the postthrombotic syndrome with venous hemodynamics and morphological abnormalities after upper extremity deep venous thrombosis. METHODS: Thirty-seven patients with a history of upper extremity deep venous thrombosis treated with anticoagulation alone underwent a single study visit (mean time after diagnosis: 44.4 ± 28.1 months). Presence and severity postthrombotic syndrome were classified according to the modified Villalta score. Venous volume and venous emptying were determined by strain-gauge plethysmography. The arm veins were assessed for postthrombotic abnormalities by ultrasonography. The relationship between postthrombotic syndrome and hemodynamic and morphological sequelae was evaluated using univariate significance tests and Spearman's correlation analysis. RESULTS: Fifteen of 37 patients (40.5%) developed postthrombotic syndrome. Venous volume and venous emptying of the arm affected by upper extremity deep venous thrombosis did not correlate with the Villalta score (rho = 0.17 and 0.19; p = 0.31 and 0.25, respectively). Residual morphological abnormalities, as assessed by ultrasonography, did not differ significantly between patients with and without postthrombotic syndrome (77.3% vs. 86.7%, p = 0.68). CONCLUSIONS: Postthrombotic syndrome after upper extremity deep venous thrombosis is not associated with venous hemodynamics or residual morphological abnormalities.

[Investigation of the practical use of a vaccination device ("Pullet Vaccinator") for young layers]. / Untersuchungen zum Einsatz des Impfautomaten "Pullet Vaccinator" in der Junghennenaufzucht.

OBJECTIVE: To evaluate the safety of layer vaccination of the vaccination device "Pullet Vaccinator", its publicised increased operational safety and the practicality of the device using serological monitoring of the vaccination success. MATERIALS AND METHODS: In a first trial, two veterinarians experienced in the syringe method vaccinated hens using the syringe and the vaccination device, respectively. After 1 hour, the equipment was switched and both veterinarians continued to vaccinate for a further hour. The second trial proceeded as in the first trial, except with untrained persons. For each of the four vaccination groups (experienced/syringe; experienced/device; untrained/syringe; untrained/device), the number of vaccinated hens was counted and 20 hens were dissected from each group to compare the impact of both inoculation methods on the animals. To monitor vaccination success, blood was collected for serological screening. On the final blood collection day, further hens per group were dissected to evaluate possible long-term injuries. RESULTS: The vaccination device offers greater occupational safety compared to the syringe method. Vaccination injuries to the hens' breast muscles were more pronounced with the syringe application. For experienced persons, the number of vaccinated animals per hour was approximately doubled using the syringe compared to the device. For the untrained, a comparable number of vaccinated animals was recorded for both methods. Serological monitoring did not show any significant differences in antibody response to the vaccination between both methods. CONCLUSION AND CLINICAL RELEVANCE: In certain points, the device proved technically imperfect and should be revised for improved use in the field.

Sonographic and clinical pattern of extracranial and cranial giant cell arteritis.

OBJECTIVES: The aim of our study was to describe the sonographic pattern and clinical manifestations of extracranial (i.e. carotid and proximal arm arteries) and cranial arterial involvement in patients with giant cell arteritis (GCA). METHODS: One hundred and ten consecutive patients with an established diagnosis of GCA between January 2002 and June 2010 were identified retrospectively from a database. All patients underwent colour duplex sonography (CDS) of the superficial temporal, carotid, and proximal arm arteries at the time of diagnosis. Circumferential, homogeneous, hypoechogenic wall thickening was regarded as a typical sign for GCA. Sonographic and clinical characteristics of patients with and without extracranial vessel involvement were compared. RESULTS: Extracranial GCA was observed in 59 of 110 subjects (53.6%). The axillary artery (48.2%) was most frequently affected and bilateral vessel involvement was present in almost all patients (94.8%). Compared to patients with cranial GCA, patients with extracranial GCA were significantly younger, frequently did not meet the American College of Rheumatology (ACR) criteria for classification of cranial GCA, exhibited a lower rate of permanent visual impairment, and were diagnosed later after onset of clinical symptoms (all p < 0.01). With increasing age, a continuous shift from GCA with extracranial arterial involvement to cranial GCA was observed. CONCLUSION: Using CDS, extracranial GCA is a common finding, most frequently observed in the axillary arteries. The clinical pattern of GCA with extracranial arterial involvement differs from that of cranial GCA.

Pseudoaneurysm of the popliteal artery due to osteochondroma of the distal femur.

Osteochondroma is the most common type of benign bone tumour, and is most often found in the knee region. The lesion is usually clinically silent although it may cause different complications such as fractures of the tumour, bone deformities, neurological disorders, malignant transformation and in rare cases vascular disorders. Vascular disorders include stenosis, occlusions, thrombosis, arteriovenous fistula and in rare cases pseudoaneurysm formation. A delay in diagnosis especially of pseudoaneurysm formation may result in life-threatening situations, extensive operations and lengthy hospital stays. We report the case of a 22-year-old woman with an osteochondroma of the distal femur which caused pseudoaneurysm of the popliteal artery.

Fever of unknown origin as initial manifestation of large vessel giant cell arteritis: diagnosis by colour-coded sonography and 18-FDG-PET.

OBJECTIVES: To evaluate the clinical characteristics and imaging results (CDS, 18-FDG-PET) of patients with large vessel giant cell arteritis (LV-GCA) presenting as fever of unknown origin (FUO). METHODS: From a series of 82 patients with GCA we identified 8 patients with FUO as initial disease manifestation. Clinical characteristics and results of CDS and 18-FDG-PET were analysed. Patients with FUO and those with other clinical manifestations of GCA were compared. RESULTS: 18-FDG-PET-scans were available for 6/8 patients, revealing enhanced tracer uptake of the thoracic aorta and the aortic branches in all patients. CDS was performed in 8/8 patients, with detection of hypoechogenic wall thickening related to LV-GCA in 7/8 patients. Subjects with FUO were significantly younger (60.9 vs. 69.3 years, p<0.01) and had a stronger humoral inflammatory response (CRP 12.6 vs. 7.1 mg/dl, p<0.01; ESR 110 vs. 71 mm/hour, p<0.01), when compared to the other GCA-patients. CONCLUSIONS: LV-GCA should be considered as important differential diagnosis in patients with FUO. In addition to 18-FDG-PET, which is known to be a valuable method in the diagnostic work-up of FUO, we recommend CDS of the supraaortal and femoropopliteal arteries for the initial diagnostic work-up.

Acute limb ischemia after femoral arterial closure with a vascular sealing device: successful endovascular treatment.

We report on successful catheter therapy of acute occlusions of popliteal and crural arteries due to distal embolization from a vascular sealing device. A 45 years-old male patient underwent percutaneous coronary angiography. After primary successful closure of the right femoral artery by a sealing device the patient developed acute ipsilateral lower limb ischemia, most probably due to embolization of a collagen/thrombin plug. Occlusions of the popliteal and crural vessels were successfully treated by percutaneous thrombectomy, thrombolysis and ballon angioplasty. Combined percutaneous catheter therapy is a therapeutic option for occlusions of popliteal and crural vessels due to embolization from a vascular sealing device.

In a pig model ePTFE grafts will sustain for 6 weeks a confluent endothelial cell layer formed in vitro under shear stress conditions.

OBJECTIVE: to investigate in a pig model whether small diameter ePTFE grafts will sustain a confluent endothelial cell layer formed in vitro under shear stress conditions. MATERIALS AND METHODS: thirteen ePTFE (4 mm) grafts were implanted end to end in the right femoral artery of; 8 grafts had been endothelialized in vitro. Grafts were left in situ for 6 weeks then evaluated with ultrasound and histology. RESULTS: seven endothelialized graft were patent with confluent endothelial cell lining. None of the control grafts were patent or showed evidence of an endothelial lining. CONCLUSION: in this pig model ePTFE grafts sustained for 6 weeks a confluent endothelial cell layer formed in vitro under shear stress.

[Duplex ultrasound for diagnosis of carotid stenosis. Detecting stroke candidates]. / Duplexsonographie zur Diagnostik von Karotisstenosen. So lassen sich Schaganfallkandidaten aufspüren.

In the hands of an experienced examiner, and with consideration being given to defined criteria, duplex sonography of the extracranial arteries supplying the brain is a valid, noninvasive, nonstressful, reproducible and comparatively inexpensive examination procedure. The indication for this examination is established after a cerebral ischemic event, or in patients with an appropriate risk profile. Nevertheless, anatomical variants or technical problems make necessary a further diagnostic work-up in the form of MR or conventional angiography.

Endothelialization of PTFE vascular grafts under flow induces significant cell changes.

BACKGROUND: To minimize thrombogeneity of small diameter PTFE grafts they are usually coated in vitro with endothelial cells under static culture conditions. The disadvantage of this technique is that a cell layer is formed that fails to withstand shear stress typical in normal blood flow. METHOD: Since the in vivo functional and structural status of endothelial cells correlates with the applied shear stress, we developed a computer-controlled perfusion system to seed and culture cells on PTFE-grafts up to a confluent monolayer under the influence of increasing shear stress. The confluence of endothelial coating was defined by immunohistological staining of cross sections, and by upper light microscopy of flattened graft samples. In addition, the expression of fibronectin as an important adhesion molecule was estimated. RESULTS AND DISCUSSION: The application of pulsatile shear stress (6.6 dyn/cm2, 5 min) to grafts endothelialized under perfusion (n = 7) did not lead to a disruption of the confluent cell layer. In contrast, a 5 min long shear stress of 3 dyn/cm2 was sufficient to wash more than 50% of cells off the PTFE-graft cultured under static conditions (n = 6). The perfusion cultures showed a significantly higher proliferation rate in comparison with static cultures. This effect was reproducibile in both serum-containing and serum-free culture media. The expression of fibronectin by endothelial cells was significantly higher in the perfused graft compared to the static one. These results suggest the practicability of endothelialized PTFE vascular grafts, preconditioned to shear rates similar to the in vivo situation, as an alternative bypass material in cardiac surgery.

["Vibration white finger" syndrome in 8 grinders of a large metal manufacturing industry]. / "Vibration-White-Finger"-Syndrom bei acht Schleifern eines grossen metallverarbeitenden Betriebes.

PATIENTS: Eight patients with vibration white finger syndrome (VWF) were seen in our angiological outpatient department. They were all turbine grinders working in the same large factory. One patient presented with a pronounced Raynaud's phenomenon only, while all the others additionally complained of numbness, weakness and pain affecting both hands. FINDINGS: We requested an intra-arterial DSA of the right hand of all patients, which in some patients revealed, in addition to severe vasospasm, also blood vessel breaks. The patient who apparently was exposed to vibration the longest also had aneurysms affecting the capillaries of all fingers.