79,265 research outputs found
THE ANALYSIS OF FIVE ELECTRONIC EMISSION SYSTEMS OF NIOBIUM NITRIDE (NbN) IN THE REGION 5000{\AA} – 6200{\AA}
No full textK. H. Rao and T. M. Dunn, Nature 222, 266 (1969). J. L. Femenias, C. Athenour, and T. M. Dunn, J. Chem. Phys. 63, 2861 (1975).Author Institution:Niobium nitride emission systems have been found at 5l37{\AA}, 5582{\AA}, 5740{\AA}, 5840{\AA}, 5860{\AA}, in addition to the already systems with subbands at 5930{\AA}, 6043{\AA}, and 6192{\AA}. Most of These systems show marked nuclear hyperfine structure of the rotational lines add this has been of assistance in the analysis of all of the systems. Systems of triplet-triplet, singlet-singlet and singlet-triplet are all present and the hyperfine structure also allows assignment of the ground and excited state electron configuration to be made with some confidence
Natural history and outcome in systemic AA amyloidosis
No full textBACKGROUND:Deposition of amyloid fibrils derived from circulating acute-phase reactant serum amyloid A protein (SAA) causes systemic AA amyloidosis, a serious complication of many chronic inflammatory disorders. Little is known about the natural history of AA amyloidosis or its response to treatment.METHODS:We evaluated clinical features, organ function, and survival among 374 patients with AA amyloidosis who were followed for a median of 86 months. The SAA concentration was measured serially, and the amyloid burden was estimated with the use of whole-body serum amyloid P component scintigraphy. Therapy for inflammatory diseases was administered to suppress the production of SAA.RESULTS:Median survival after diagnosis was 133 months; renal dysfunction was the predominant disease manifestation. Mortality, amyloid burden, and renal prognosis all significantly correlated with the SAA concentration during follow-up. The risk of death was 17.7 times as high among patients with SAA concentrations in the highest eighth, or octile, (greater/equal 155 mg per liter) as among those with concentrations in the lowest octile (< 4 mg per liter); and the risk of death was four times as high in the next-to-lowest octile (4 to 9 mg per liter). The median SAA concentration during follow-up was 6 mg per liter in patients in whom renal function improved and 28 mg per liter in those in whom it deteriorated (P < 0.001). Amyloid deposits regressed in 60% of patients who had a median SAA concentration of less than 10 mg per liter, and survival among these patients was superior to survival among those in whom amyloid deposits did not regress (P=0.04).CONCLUSIONS:The effects of renal dysfunction dominate the course of AA amyloidosis, which is associated with a relatively favorable outcome in patients with SAA concentrations that remain in the low-normal range (< 4 mg per liter)
Renal AA-amyloidosis in intravenous drug users - a role for HIV-infection?
No full textBackground: Chronic renal disease is a serious complication of long-term intravenous drug use (IVDU). Recent reports have postulated a changing pattern of underlying nephropathy over the last decades.
Methods: Retrospective investigation including all patients with prior or present IVDU that underwent renal biopsy because of chronic kidney disease between 01.04.2002 and 31.03.2012 in the city of Frankfurt/Main, Germany.
Results: Twenty four patients with IVDU underwent renal biopsy because of progressive chronic kidney disease or proteinuria. Renal AA-amyloidosis was the predominant cause of renal failure in 50% of patients. Membranoproliferative glomerulonephritis (GN) was the second most common cause found in 21%. Patients with AA-amyloidosis were more likely to be HIV infected (67 vs.17%; p=0.036) and tended to have a higher rate of repeated systemic infections (92 vs. 50%; p=0.069). Patients with AA-amyloidosis presented with progressive renal disease and nephrotic-range proteinuria but most patients had no peripheral edema or systemic hypertension. Development of proteinuria preceded the decline of GFR for approximately 1--2 years.
Conclusions: AA-amyloidosis was the predominant cause of progressive renal disease in the last 10 years in patients with IVDU. The highest rate of AA-amyloidosis observed was seen in HIV infected patients with IVDU. We speculate that chronic HIV-infection as well as the associated immunosuppression might promote development of AA-amyloidosis by increasing frequency and duration of infections acquired by IVDU
Eprodisate for the treatment of renal disease in AA amyloidosis
No full textBackground: Amyloid A (AA) amyloidosis is a complication of chronic inflammatory conditions that develops when proteolytic fragments of serum amyloid A protein (SAA) are deposited in tissues as amyloid fibrils. Amyloid deposition in the kidney causes progressive deterioration in renal function. Eprodisate is a member of a new class of compounds designed to interfere with interactions between amyloidogenic proteins and glycosaminoglycans and thereby inhibit polymerization of amyloid fibrils and deposition of the fibrils in tissues.
Methods: We performed a multicenter, randomized, double-blind, placebo-controlled trial to evaluate the efficacy and safety of eprodisate in patients with AA amyloidosis and kidney involvement. We randomly assigned 183 patients from 27 centers to receive eprodisate or placebo for 24 months. The primary composite end point was an assessment of renal function or death. Disease was classified as worsened if any one of the following occurred: doubling of the serum creatinine level, reduction in creatinine clearance by 50% or more, progression to end-stage renal disease, or death.
Results: At 24 months, disease was worsened in 24 of 89 patients who received eprodisate (27%) and 38 of 94 patients given placebo (40%, P=0.06); the hazard ratio for worsening disease with eprodisate treatment was 0.58 (95% confidence interval, 0.37 to 0.93; P=0.02). The mean rates of decline in creatinine clearance were 10.9 and 15.6 ml per minute per 1.73 m2 of body-surface area per year in the eprodisate and the placebo groups, respectively (P=0.02). The drug had no significant effect on progression to end-stage renal disease (hazard ratio, 0.54; P=0.20) or risk of death (hazard ratio, 0.95; P=0.94). The incidence of adverse events was similar in the two groups.
Conclusions: Eprodisate slows the decline of renal function in AA amyloidosis
AA-deficient <i>sfx</i> mice had decreased articular cartilage.
No full text(A) Representative sections of articular cartilage from control sfx/+ mice and AA-deficient sfx/sfx mice stained with Safranin-O. Articular cartilage was quantitated using the OsteoMeasure software, and sfx/sfx mice had less articular cartilage area (B) and width (C) at the femur and tibia. OARSI scores (D) are shown for sfx/+ and sfx/sfx mice. Results are presented as mean ± SEM. *P t-test), n = 6 per group.</p
Cu(II)-catalyzed reactions in ternary [Cu(AA)(AA - H)]+ complexes (AA = Gly, Ala, Val, Leu, Ile, t-Leu, Phe).
No full textInternational audienceThe unimolecular chemistry of [Cu(II)AA(AA - H)](+) complexes, composed of an intact and a deprotonated amino acid (AA) ligand, have been probed in the gas phase by tandem and multistage mass spectrometry in an electrospray ionization quadrupole ion trap mass spectrometer. The amino acids examined include Gly, Ala, Val, Leu, Ile, t-Leu and Phe. Upon collisionally-activated dissociation (CAD), the [Cu(II)AA(AA - H)](+) complexes undergo decarboxylation with simultaneous reduction of Cu(II) to Cu(I); during this process, a radical site is created at the alpha-carbon of the decarboxylated ligand (H(2)N(1) - (*)C(alpha)H - C(beta)H(2) - R; R = side chain substituent). The radical site is able to move along the backbone of the decarboxylated amino acid to form two new radicals (HN(1)(*) - C(alpha)H(2) - C(beta)H(2) - R and H(2)N(1) - C(alpha)H(2) - (*)C(beta)H - R). From the complexes of Gly and t-Leu, only C(alpha) and N(1) radicals can be formed. The whole radical ligand can be lost to form [Cu(I)AA](+) from these three isomeric radicals. Alternatively, further radical induced dissociations can take place along the backbone of the decarboxylated amino acid ligand to yield [Cu(II)AA(AA - 2H - CO(2))](+), [Cu(I)AA((*)NH(2))](+), [Cu(I)AA(HN = C(alpha)H(2))](+), or [Cu(I)AA(H(2)N - C(alpha)H = C(beta)H - R'](+) (R' = partial side chain substituent). The sodiated copper complexes, [Cu(II)(AA - H + Na)(AA - H)](+), show the same fragmentation patterns as their non-sodiated counterparts; sodium ion is retained on the intact amino acid ligand and is not involved in the CAD pathways. The amino groups of both AA units, the carbonyl group of the intact amino acid, and the deprotonated hydroxyl oxygen coordinate Cu(II) in square-planar fashion. Ab initio calculations indicate that the metal ion facilitates hydrogen atom shuttling between the N(1), C(alpha) and C(beta) atoms of the decarboxylated amino acid ligand. The dissociations of the decarboxylated radical ions unveil important insight about the so far largely unknown intrinsic chemistry of alpha-amino acid and peptide radicals, which are implicated as intermediates in numerous pathogenic biological processes
Distinguishing diffuse alopecia areata (AA) from pattern hair loss (PHL) using CD3+ T cells
No full textDistinguishing between diffuse subacute alopecia areata (AA), in which the peribulbar infiltrate is absent, and pattern hair loss is challenging, particularly in cases that lack marked follicular miniaturization and a marked catagen/telogen shift. Objective We sought to distinguish diffuse AA from pattern hair loss using CD3+ T lymphocytes. Methods A total of 28 cases of subacute AA and 31 cases of pattern hair loss were selected and a 4-mm punch biopsy was performed. All the specimens were processed using the "HoVert" (horizontal and vertical) technique. In all cases, hematoxylin-eosin and immunohistochemical stains for CD3, CD4, CD8, and CD20 were performed. Results The presence of CD3+ lymphocytes within empty follicular fibrous tracts (stela), even without a concomitant peribulbar infiltrate, is a reliable histopathological clue in supporting a diagnosis of AA (sensitivity 0.964, specificity 1, P ≤.001). Limitations Limited tissue for analysis remained in the clinical sample tissue blocks. Conclusion The presence of CD3+ T-cells within empty follicular fibrous tracts (stela) supports a diagnosis of AA.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
AA-deficient <i>sfx</i> mice had less trabecular bone at the femoral primary and secondary spongiosa.
No full textRepresentative microCT images of (A) primary and (B) secondary spongiosa from control sfx/+ mice and AA-deficient sfx/sfx mice. Scans were quantitated by (C) bone volume adjusted for tissue volume (BV/TV), (D) trabecular number, (E) trabecular thickness, and (F) trabecular separation. Results are presented as mean ± SEM. *P t-test), n = 6 per group.</p
MCs in lesional AA skin up-regulate co-stimulatory molecules for CD8+ T-cells.
No full text<p>Immunohistochemical identification of OX40L+/tryptase+ MCs, detected using OX40L/CD8/tryptase staining (A–E) and CD30L+/c-Kit+ MCs, detected using CD30L/c-Kit (M), showing the expression pattern of OX40L (A–E) and CD30L (M) within MCs, in human scalp skin of controls (A,B,D,M) and AA patients (C,E). Higher magnification of OX40L+/tryptase+ (F) and CD30L+/c-Kit+ (N) MCs. Representative pictures of OX40L+ (G) and OX40L− (H) (detected by tryptase) and CD30L− (O) and CD30L+ (P) (detected by c-Kit) MCs interacting with CD8+ T-cells. Immunohistochemical identification of OX40L+/tryptase+ (I,J) and CD30L+/c-Kit+ (Q,R) MCs and CD8+ T-cells in human HFs from lesional (I,Q), non-lesional (J) AA and healthy (R) skin. Brown cells are OX40L+ (A–J) or CD8+ (M–R) cells (brown arrows), blue cells are CD8+ (A–J) or c-Kit+ (M–R) cells (blue arrows), pink cells are tryptase+ cells (A–J) (pink arrows), red cells are CD30L+ cells (M–R) (red arrows), pink-brown cells are OX40L+/tryptase+ cells (A-J) and blue-red cells are CD30L+/c-Kit+ cells (M–R) (green arrows). Quantitative analysis of the % of OX40L+/tryptase+ MCs among all MCs (K), OX40L+/tryptase+ MCs interacting with CD8+ T-cells (L) and the % of CD30L+/c-Kit+ MCs among all MCs (S) in AA patients compared to controls. Analysis derived from 17–21 areas of 6–14 HFs of 6–7 healthy control and of 11–21 areas of 4–12 HFs of 3 AA patients for non-lesional skin and of 17–21 areas of 16–17 HFs of 7 AA patients for lesional skin. ±SEM ***p≤0.001, **p≤0.01, *p≤0.05 ±SEM, One-Way ANOVA or Kruskal-Wallis test followed respectively by Bonferroni's or Dunn's multiple comparison tests. Immunohistochemical identification of 4–1BBL+/c-Kit+ and 4-1BBL-/c-Kit+ MCs, detected using 4–1BBL/c-Kit/CD8 staining (T–W) and of ICAM-1+/tryptase+ and ICAM-1-/tryptase+ MCs, detected using ICAM-1/CD8/Tryptase staining (X-AA), around the HF bulb of AA patient (T,X) and control (W,Z). Representative pictures of 4–1BBL+/c-Kit+ (U), 4–1BBL-/c-Kit+ MCs (V), ICAM-1-/tryptase+ (Y) and ICAM-1+/tryptase+ (AA) MCs interacting with CD8+ T-cells. Brown cells are CD8+ (T–W) or ICAM-1+ (X-AA) cells (brown arrows), blue cells are c-Kit+ MCs (T–W) or CD8+ cells (X-AA) (blue arrows), red cells are 4–1BBL+ cells (T–W) (red arrows), pink cells are tryptase+ cells (X-AA) (pink arrows), blue-red cells are 4–1BBL+/c-Kit+ MCs (T–W) and pink-brown cells are ICAM-1+/tryptase+ MCs (X-AA) (green arrows). These stainings were observed in one section/subject of 6–8 healthy individuals and non-lesional skin from 4 AA patients and lesional skin from 11 AA patients. Scale bars: 20 µm (A–C, N–P,AA), 10 µm (D–E,U,V,Y), 5 µm (F–H), 50 µm (I–J,M,Q,R,T,W,X,Z). Connective tissue sheath (CTS), dermal papilla (DP), hair follicle (HF), hair matrix (HM), perifollicular dermis (PFD).</p
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