Variable-sagittal-radii elliptical x-ray crystal spectrometers for high-neutron-yield plasma diagnostics.

Sagittally focusing x-ray crystal spectrometers with elliptical profiles in the meridional (x-ray dispersion) plane are proposed for plasma diagnostics in experiments accompanied by high neutron yields. The spectrometers feature a variable sagittal radius of curvature to ensure the sagittal focusing of rays for each photon energy in a chosen detection plane. The detector is placed after the ray crossing point at the second ellipse focus, and the source-to-detector distance is maximized to reduce the neutron-induced background. The elliptical shape imposes a limitation on the spectrometer geometry such that the influence of the source size on the spectral resolution can be avoided only for a demagnifying spectrometer (the source-to-crystal distance is larger than that of crystal-to-detector). Hence, two designs are proposed. The first design, featuring high magnification and limited spectral resolution can be suitable for x-ray continuum spectroscopy. The second design of high demagnification is optimized for spectral resolution, and can be used for time-resolved spectroscopy of plasma's characteristic emission lines using streak cameras. The key performance characteristics of the two designs are verified using ray tracing.

A new class of variable-radii diffraction optics for high-resolution x-ray spectroscopy at the National Ignition Facility (invited).

A new class of crystal shapes has been developed for x-ray spectroscopy of point-like or small (a few mm) emission sources. These optics allow for dramatic improvement in both achievable energy resolution and total throughput of the spectrometer as compared with traditional designs. This class of crystal shapes, collectively referred to as the Variable-Radii Spiral (VR-Spiral), utilize crystal shapes in which both the major and minor radii are variable. A crystal using this novel VR-Spiral shape has now been fabricated for high-resolution Extended X-ray Absorption Fine Structure (EXAFS) experiments targeting the Pb-L3 (13.0 keV) absorption edge at the National Ignition Facility. The performance of this crystal has been characterized in the laboratory using a microfocus x-ray source, showing that high-resolution high-throughput EXAFS spectra can be acquired using this geometry. Importantly, these successful tests show that the complex three-dimensional crystal shape is manufacturable with the required precision needed to realize the expected performance of better than 5 eV energy resolution while using a 30 mm high crystal. An improved generalized mathematical form for VR-Spiral shapes is also presented allowing improved optimization as compared to the first sinusoidal-spiral based design. This new formulation allows VR-Spiral spectrometers to be designed at any magnification with optimized energy resolution at all energies within the spectrometer bandwidth.

CBETA: First Multipass Superconducting Linear Accelerator with Energy Recovery.

Energy recovery has been achieved in a multipass linear accelerator, demonstrating a technology for more compact particle accelerators operating at higher currents and reduced energy consumption. Energy delivered to the beam during the first four passes through the accelerating structure was recovered during four subsequent decelerating passes. High-energy efficiency was achieved by the use of superconducting accelerating cavities and permanent magnets. The fixed-field alternating-gradient optical system used for the return loop successfully transported electron bunches of 42, 78, 114, and 150 MeV in a common vacuum chamber. This new kind of accelerator, an eight-pass energy recovery linac, has the potential to accelerate much higher current than existing linear accelerators while maintaining small beam dimensions and consuming much less energy per electron.

Nuclear mapping in parathyroidectomy: the impact on operative time.

BACKGROUND: Precise intraoperative localization and identification of hyperactive parathyroid tissue remains one of the most challenging tasks for surgeons performing parathyroidectomies. Among a few adjuvant methods tested recently, a novel technique called nuclear mapping may become a real breakthrough in parathyroid surgery. It is based on intraoperative detection of radioactivity after previous intravenous administration of 99mTc Sestamibi, which is accumulated in hyperactive parathyroid tissue. The purpose of this study was to assess the impact of nuclear mapping on operative time in parathyroidectomy. METHODS: The study was conducted as a retrospective univariable and multivariable analysis of clinical factors potentially influencing the operative time in a group of 27 patients undergoing parathyroidectomy. RESULTS: Univariable analysis revealed that nuclear mapping was associated with significant reduction in operative time (79.4 +/- 62.2 min vs. 135.8 +/- 49.2 min; p = 0.0186); whereas, bilateral neck exploration, partial sternotomy and reoperative neck prolonged the procedure by mean 70.7 +/- 12.9 min (p = 0.0035); 100,9 +/- 50.36 min (p = 0.0154) and 73.3 +/- 22.8 min (p = 0.0081), respectively. Multivariable analysis using a multiple regression model identified nuclear mapping, sternotomy and reoperative neck as independent variables significantly influencing the duration of parathyroidectomy. CONCLUSIONS: Nuclear mapping is an efficient intraoperative adjuvant technique facilitating localization of hyperactive parathyroid tissues in vivo and instantly confirming their identity ex vivo. It guides the surgeon throughout the parathyroidectomy and is associated with significant reduction in operative time.

CD95 is not functional in human erythrocytes.

INTRODUCTION: The CD95 pathway is a potent inducer of apoptosis in nucleated cells and this death receptor is important for proper blood cell development. Although it is expressed in red blood cells, its functional role in erythrocytes is not well documented. These anucleated cells can undergo cell death via eryptosis, a process showing similarities to apoptosis of nucleated cells. This mode of cell death is mainly triggered by oxidative stress or energy depletion. METHODS: CH11 was added to the purified human erythrocytes for induction of phosphatidylserine (PS) exposure. AnnexinV-FITC was used as a probe for PS detection. RESULTS: No significantly enhanced PS-positive cell fraction could be observed after erythrocytes were treated with CH11. CONCLUSION: Based on some key features for an activated CD95 system, this death receptor has been considered to induce PS exposure. However, we give evidence, that CD95 is not functional in red blood cells and that activation of this death receptor does not lead to the exposure of phosphatidylserine.

Altered signaling of TNFalpha-TNFR1 and SODD/BAG4 is responsible for radioresistance in human HT-R15 cells.

Radioresistance in pre-irradiated human HT-R15 cells is associated with changes of the TNFR1-dependent death pathway. HT-R15 cells are characterized by elevated protein levels of TNFR1 and TNF and by increased sensitivity to exogenous TNFalpha compared to their parental HT-29 cells. Alterations are also observed downstream in the signaling cascade, such as the activation of NF-kappaB or the overexpression of the death domain kinase RIP and reduced caspase 8 activity. However, these changes seem to be a consequence of defective upstream TNFalpha signaling rather than the primary cause of cellular resistance in HT-R15 cells. Of major importance for resistance in HT-R15 cells is the silencer of death domain, SODD/BAG4. Following gamma-irradiation, the membrane-associated 49 kDa SODD decreases in the parental but not in the resistant cells, whereas after TNFalpha treatment, SODD expression declines only in the resistant cells. A 42 kDa cytoplasmic SODD protein is detected, which is elevated only in the resistant cells. This SODD protein is not involved in the regulation of cell survival after radiation or TNFalpha treatment but rather in altered TNFR1 shedding. Inhibition of TNFR1 release by the metalloprotease inhibitor BB-2516 results in a significant increase of the 42 kDa SODD protein without affecting cell survival in sensitive or resistant HT cells. Moreover, TNFR1 release into the culture medium is augmented in the resistant cells. These results suggest that defective TNFalpha signaling and/or altered silencing by SODD/BAG4 in HT-R15 cells are involved in the radiation resistance of HT-R15 cells and also affect the paracrine functions of TNFR1. Resistance is circumvented by TNFalpha treatment, independent of cytoplasmic TNFalpha/TNFR1 functions.

Principles of induction chemotherapy for non-small cell lung cancer.

The results of lung cancer treatment have not significantly improved for many years. About 35% of patients with non-small cell lung cancer (NSCLC) are in clinical stage IIIA. Clinically asymptomatic distant metastases occur in the majority of these patients. In such cases only combined treatment offers a chance of cure. In the Chest Surgery Center in Lublin a clinical trial was carried out aimed to assess late results of combined treatment in patients with IIIA NSCLC. Over 700 patients were enrolled in the study. The results of the trial disclosed, that neoadjuvant chemotherapy prolonged life of the operated patients and improved their life quality. However, a question of qualification for this complex treatment and complexity of assessment criteria, still remain to be answered.

IkappaB/NF-kappaB mediated cisplatin resistance in HeLa cells after low-dose gamma-irradiation is associated with altered SODD expression.

Fractionated gamma-irradiation (15 x 2 Gy in 3 weeks) induces a cellular resistance in HeLa cells against cisplatin exposure but not against irradiation. The mechanisms underlying this cellular resistance are associated with major changes in the TNFR1-dependent transduction pathway. The resistant HeLa/B cells exhibit increased levels of NF-kappaB with temporally independent regulation of the subunits NF-kappaB50 and NF-kappaB65. Blocking IkappaB degradation by the proteasome inhibitor PSI, which abolishes the release of the active NF-kappaB protein, induces cell death much more effectively in the parental than in the resistant HeLa/B cells. The translocation of NF-kappaB does not seem to be affected in a similar manner since masking of the translocation sequence by NF-kappaB SN50 enhances cisplatin toxicity to the same degree in both cell lines and overcomes drug resistance. Changes in upstream signaling are suggested by increased sensitivity of the parental HeLa cells to cisplatin in the presence of neutralizing anti-TNFR1. In HeLa/B cells, reduced expression of the 50 kDa silencer of death domain, SODD, is accompanied by constitutive overexpression of a 40-42 kDa SODD-like protein. A possible involvement of SODD in cisplatin resistance is discussed, which may shift the balance between life and death in the TNF receptor pathway to increased NF-kappaB activation.

[Importance of scintigraphy in the evaluation of surgical treatment outcome in differentiated cancer of the thyroid gland]. / Znachenie stsintigrafii v otsenke iskhoda khirurgicheskogo lecheniia differentsirovannogo raka shchitovidnoi zhelezy.

Experience of radionuclide investigation in 493 patients with differentiated cancer of thyroid gland is summarized. The consequences due to incorrect conducting of patients with cancer after the operation were adduced on distinct examples. The program for conducting and observation of patients with thyroid gland cancer after the operation conduction was proposed directed on the early diagnosis of recurrencies and metastases, determination of indications for radioiodine therapy.

[Changes in the beta 2-microglobulin levels of the blood serum in patients with benign and malignant neoplasms]. / Izmenenie urovnia beta 2-mikroglobulina v syvorotke krovi bol'nykh s dobrokachestvennymi i zlokachestvennymi novoobrazovaniiami.

Radioimmunological examination of beta 2-microglobulin in the blood serum of 525 patients revealed that increased protein levels were observed in patients with malignant tumours of the pancreas, duodenal papilla, ovaries, soft tissues, lymphomas. In benign diseases (pancreatitis, ovarian cysts) the beta 2-microglobulin concentration did not significantly exceed the discrimination value. Due to the low sensitivity and specificity this protein has dubious significance as a tumour marker. It is suggested that in some cases of malignant tumours changes of the beta 2-microglobulin level may be related to hepatorenal insufficiency, spread of the disease. These data may provide supplementary information on the prognosis and evolution of the tumour process after combined treatment.

[CA 125 in the diagnosis and evaluation of the efficacy of the treatment of cancer of the ovaries]. / CA 125 dlia diagnostiki i otsenki éffektivnosti terapii raka iachnikov.

The paper is concerned with the results of CA-125 radioimmunoassay in 163 patients (584 tests) with benign and malignant ovarian diseases and other small pelvic diseases which were diagnosed before operation as ovarian tumors. CA-125 radioimmunoassay can be used in combination with other methods for investigation of patients with suspected ovarian cancer and for differential diagnosis of malignant ovarian tumors to distinguish them from other malignant tumors of the small pelvis. The total accuracy of the method, its sensitivity and specificity were 94.6%, 96.9 and 93.2%, respectively. CA-125 levels were considerably increased in malignant ovarian tumors irrespective of their histological structure. The investigation of CA-125 indices in the course of disease was indicative of the effectiveness of antitumor therapy.

Cannibal's relief: the origins of sex.

Microorganisms in the gut of a cockroach resemble those that lived on earth 2000 million years ago. One of their activities, eating each other, may hold the key to the history of sexual reproduction in today's animals and plants.

Community living long before man: fossil and living microbial mats and early life.

Microbial mats are layered communities of bacteria that form cohesive structures, some of which are preserved in sedimentary rocks as stromatolites. Certain rocks, approximately three and a half thousand million years old and representing the oldest known fossils, are interpreted to derive from microbial mats and to contain fossils of microorganisms. Modern microbial mats (such as the one described here from Matanzas, Cuba) and their fossil counterparts are of great interest in the interpretation of early life on Earth. Since examination of microbial mats and stromatolites increases our understanding of long-term stability and change, within the global environment, such structures should be protected wherever possible as natural science preserves. Furthermore, since they have existed virtually from the time of life's origin, microbial mats have developed exemplary mechanisms of local community persistence and may even play roles in the larger global environment that we do not understand.

Order amidst animalcules: the Protoctista kingdom and its undulipodiated cells.

The eukaryotic microorganisms have always been studied and described in the context of Zoology (as tiny animals), Botany (as tiny plants), Mycology (as water molds) or Microbiology (as disease agents). Because their extent (as a group of about 200,000 species) and differences from the rest of life (worthy of Protoctista kingdom status) only recently has been recognized, their classification within the Plant and Animal kingdoms remains in scandalous disarray. Admitting this problem, this paper represents a step toward achieving nomenclatural order based on ultrastructural, biochemical and evolutionary considerations.