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1.
The effects of Captopril, an angiotensin-converting enzyme inhibitor, on pulmonary hemodynamics and blood gases were studied in 9 patients with chronic obstructive lung disease (COLD) and pulmonary hypertension (PA-P greater than 20 mm Hg). Hemodynamic data were recorded prior to Captopril administration (50 mg per os) and for the next 60 min. Following Captopril administration, significant reductions in mean pulmonary artery pressure (PA-P) (p less than 0.05), in mean pulmonary wedge pressure (PW-P) (p less than 0.05), and in total pulmonary resistance (TPR) were noted; significant reductions in mean brachial artery pressure (BA-P) and systemic vascular resistance (SVR) were also recorded, while cardiac output, heart rate and blood gas tensions showed no significant changes. Furthermore, the higher the hypoxemia, the greater was the reduction in BA-P (p less than 0.05). We therefore feel that Captopril, when administered to COLD patients with pulmonary hypertension, may protect the pulmonary circulation from hypoxic pulmonary vasoconstriction.  相似文献   
2.
The cause(s) of sarcoidosis is unknown. Mycobacterium spp. are suspected in Europe and Propionibacterium spp. are suspected in Japan. The present international collaboration evaluated the possible etiological links between sarcoidosis and the suspected bacterial species. Formalin-fixed and paraffin-embedded sections of biopsy samples of lymph nodes, one from each of 108 patients with sarcoidosis and 65 patients with tuberculosis, together with 86 control samples, were collected from two institutes in Japan and three institutes in Italy, Germany, and England. Genomes of Propionibacterium acnes, Propionibacterium granulosum, Mycobacterium tuberculosis, Mycobacterium avium subsp. paratuberculosis, and Escherichia coli (as the control) were counted by quantitative real-time PCR. Either P. acnes or P. granulosum was found in all but two of the sarcoid samples. M. avium subsp. paratuberculosis was found in no sarcoid sample. M. tuberculosis was found in 0 to 9% of the sarcoid samples but in 65 to 100% of the tuberculosis samples. In sarcoid lymph nodes, the total numbers of genomes of P. acnes or P. granulosum were far more than those of M. tuberculosis. P. acnes or P. granulosum was found in 0 to 60% of the tuberculosis and control samples, but the total numbers of genomes of P. acnes or P. granulosum in such samples were less than those in sarcoid samples. Propionibacterium spp. are more likely than Mycobacteria spp. to be involved in the etiology of sarcoidosis, not only in Japanese but also in European patients with sarcoidosis.  相似文献   
3.
G Rizzato  P Fraioli  L Montemurro 《Chest》1991,99(2):301-309
PURPOSE: To evaluate the long-term action of deflazacort (DF), a new calcium-sparing and bone-saving corticosteroid, in chronic sarcoidosis patients needing prolonged therapy. PATIENTS AND METHODS: 40 patients with chronic histologically proved sarcoidosis requiring long-term corticosteroid therapy were treated with DF and followed for a mean period of 958 +/- 515 days (range 382-2, 068). The indication for giving corticosteroid therapy was pulmonary impairment in most (36), but also other events including hypercalcemia (2), kidney stones (5, 2 with recurrent colic), uveitis (2), lupus pernio (3), suspected heart impairment (5), hypersplenism (1), and other causes. Follow-up examination included serial ACE, chest x-ray, 67Ga lung scan, pulmonary function data, serum and urinary calcium levels. Eleven patients (UT group) were not receiving glucocorticoids when first seen at our clinic; 29 patients (PT group) were on therapy with glucocorticoids (27 wity prednisone, 2 with DF) for 870 +/- 1,128 days (range 27-4,310) RESULTS: In the PT group, DF maintained the good results previously obtained with prednisone; in this group, chest x-ray film showed improvement in 16 patients, 67Ga lung scan was better in 13, while worsening chest x-ray film findings in 1 and 67Ga lung scan in 2 was seen coincident with DF tapering. Respiratory function data showed a mild nonsignificant improvement. SACE decreased significantly from 114.6 +/- 38.7 to 91.5 +/- 37.9 nM/ml/min (p less than .05). In the UT group the results were better, as expected in a population where the action of corticosteroids did not influence the first observation. FVC increased significantly from 76.3 +/- 13.0 to 89.9 +/- 19.5 percent predicted (p less than .01); the 67Ga lung scan and chest x-ray film findings improved in all but 1 patient, and ACE dropped significantly (p less than .01) from 131.8 +/- 46.3 to 83.7 +/- 25.0. In both groups the side effects were mild, and only 2 patients discontinued the treatment, 1 for gastric ulcer, and the other for amenorrhea plus a 14 kg weight gain. CURRENT STATUS: One patient died of cancer, 9 discontinued treatment (5 because therapy was no longer necessary, 2 for the above described side effects, 2 for non-drug-related reasons), 4 dropped out and were last seen when taking DF 22.5, 18, 12 and 6 mg daily respectively. Twenty-six are continuing the drug on a long-term basis at the current mean daily dose of 12.1 +/- 7.3 mg (range 3-30). In a number of these, an attempt to discontinue DF resulted in a sarcoid relapse, and DF was restarted. CONCLUSION: DF is a good and safe approach to the long-term corticosteroid therapy of sarcoidosis.  相似文献   
4.
The Italian national transplantation network has set up programs for liver, heart, and lung transplantation in urgent conditions. The aim of this study was to analyze the capability of these programs to meeting needs and their quality.  相似文献   
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6.
NMR is a noninvasive, molecular-level spectroscopic technique widely used for chemical characterization. However, it lacks the sensitivity to probe the small number of spins at surfaces and interfaces. Here, we use nitrogen vacancy (NV) centers in diamond as quantum sensors to optically detect NMR signals from chemically modified thin films. To demonstrate the method’s capabilities, aluminum oxide layers, common supports in catalysis and materials science, are prepared by atomic layer deposition and are subsequently functionalized by phosphonate chemistry to form self-assembled monolayers. The surface NV-NMR technique detects spatially resolved NMR signals from the monolayer, indicates chemical binding, and quantifies molecular coverage. In addition, it can monitor in real time the formation kinetics at the solid–liquid interface. With our approach, we show that NV quantum sensors are a surface-sensitive NMR tool with femtomole sensitivity for in situ analysis in catalysis, materials, and biological research.

The characterization of surface processes at the molecular level is essential for understanding fundamental processes in industrial catalysis, energy conversion, electronic circuits, targeted drug delivery, and biosensing (1). However, many analytical techniques used in surface science are inaccessible under ambient or chemically relevant conditions. Therefore, it remains challenging to perform chemical analysis under the conditions in which these processes occur (2, 3). Commonly used surface sensitive methods, such as X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy, and secondary ion mass spectroscopy can perform chemical analysis but require ultra-high vacuum and expensive equipment (4). Great efforts have been devoted to extending XPS analysis to near ambient conditions (2). Indeed, both near-ambient pressure XPS and extended X-ray absorption fine structure have significantly expanded the applicability of these X-ray–based techniques for understanding reaction mechanisms at chemically active interfaces (2, 5). However, both methods require intense synchrotron radiation to achieve high sensitivity and resolution, which limits their practical accessibility and increases their cost. State-of-the-art surface-sensitive spectroscopy techniques, such as sum frequency generation and second harmonic generation, can perform analysis under ambient conditions but require technically complex equipment such as femtosecond lasers (6). Even with all these techniques available, molecular dynamics or chemical reaction kinetics at surfaces are still challenging to probe experimentally (7) (SI Appendix, Supplementary Note 1).NMR spectroscopy is one of the major tools for chemical and structural analysis in chemistry, biology, and materials science. Solid-state NMR in particular (8) has advanced understanding of a range of systems, including metal organic frameworks (9), batteries (10), and catalysts (11). However, sensitivity remains a challenge for traditional NMR spectroscopy, making studies at surfaces difficult because of the limited numbers of nuclear spins. Recently, surface-enhanced NMR spectroscopy (DNP-SENS) relying on hyperpolarization such as dynamic nuclear polarization (12, 13) or xenon-based techniques (14) gained research momentum and enabled probing spins located at surfaces. However, even in highly porous materials with greater than 1,000 m2/g surface area, the concentration of NMR-active nuclei of interest often remains low (e.g., 1 mmol of surface atoms/g), which requires long averaging times to obtain solid-state NMR spectra with reasonable signal-to-noise ratios (SNR) (12) (SI Appendix, Supplementary Note 2).Here, we demonstrate the use of quantum sensors in diamond as a surface-sensitive spectroscopy technique that works at ambient conditions and can probe planar interfaces on the microscopic length scale with far greater sensitivity (femtomoles, see Materials and Methods) than conventional NMR. The spectroscopic technique relies on the nitrogen vacancy (NV) point defect, consisting of a nitrogen impurity (N) and an adjacent vacancy (V) in the carbon lattice of diamond. These spin-1 defects allow for optical detection of magnetic resonance and have been established as highly sensitive nanoscale magnetic field sensors (15, 16). Near-surface NV centers are sensitive to magnetic fields from the Larmor precession of nuclei from samples positioned outside of the diamond. This enables nanoscale NMR detection—even down to a single molecule (17) or spin (18, 19). The measurement volume of such NV sensors (20, 21) corresponds to a hemisphere whose radius is roughly their depth below the surface in the diamond lattice (e.g., 5 to 10 nm). At this small length scale, the thermal polarization of the nuclear spins can be neglected since spin noise dominates for a small number of spins (22, 23). For that reason, the NMR signal strength is independent of the applied magnetic field B0, reducing experimental complexity and costs, which makes the technique accessible to a broader community. Previously published nanoscale NV-NMR experiments detected NMR signals from either bulk samples [such as viscous oils (21, 22, 24)] or samples tethered to (17) or placed directly on the diamond surface (25). In this work, we propose the use of NV centers in diamond combined with state-of-the-art thin film deposition techniques as a general platform to detect NMR signals with high sensitivity and spatial resolution even from nondiamond surfaces. This approach is general and allows for the probing of a variety of surfaces and interfaces with NMR, thereby enabling their chemistry to be explored. Here, we use atomic layer deposition (ALD), a technology that can be applied to synthesize films of a wide variety of materials with high thickness precision to coat the diamond with amorphous aluminum oxide (Al2O3). Al2O3 provides an exemplary surface of high technical relevance in optoelectronic applications and acts as structural support in various catalytic processes (26). In a proof-of-concept study for this surface-sensitive spectroscopic technique, we probe the chemical modification of the Al2O3 surface with phosphonate anchoring during the formation of a self-assembling monolayer (SAM) (27).  相似文献   
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8.
Adenine and guanine nucleotides have been shown to exert multiple roles in central and peripheral nervous systems, and the sequential breakdown of these nucleotides by enzymatic systems is an important step in the modulation of their extracellular effects. The aim of this study was to investigate whether nucleotide hydrolysis also occurs in the cerebrospinal fluid (CSF) of rats. CSF was able to hydrolyze all guanine and adenine nucleotides investigated (2.0 mM): GDPADP=ATP=GTPAMP=GMP. More detailed studies with the diphosphate nucleotides showed that the hydrolysis of ADP and GDP was linear with incubation time and protein concentration. The apparent KM (Henry–Michaelis–Menten constant) and V (maximal velocity) values for ADP and GDP were 164.3±54.7 μM and 12.2±3.8 nmol Pi/min per mg protein, and 841.0±90.2 μM and 22.8±8.0 nmol Pi/min per mg protein. The sum of ADP, GDP and UDP hydrolysis (2.0 mM) upon individual incubations with CSF was similar to the hydrolysis observed when all three nucleotides were incubated together. This pattern of hydrolysis strongly suggests the involvement of more than one enzyme activity. The higher maximum activity for GDP and UDP compared to ADP is compatible with presence of a soluble NTDPase5.  相似文献   
9.
The Congress gathered together for two days most of the leading world authorities in the field of interstitial lung diseases: it was an outstanding basic and clinical update on most of the rare pulmonary diseases and orphan drugs in respiratory medicine. Here we examine the latest information outlined in the lectures and relative discussions, paying particular attention to anything of interest from a clinical point of view.  相似文献   
10.

Purpose of review

The purpose of this study was to retrospectively evaluate the use of carmustine wafers (CWs) in the management of high-grade gliomas (HGGs). The data from our monoinstitutional series was compared with studies reported in the literature. Special emphasis was placed on the evaluation of side effects and the analysis of extent of resection and molecular profile as risk factors.

Recent findings

The implantation of CWs into the resection cavity during HGG treatment to deliver localized chemotherapy, followed by the Stupp protocol, remains debated in a clinical setting, largely due to the lack of appropriate phase III studies. Given the high expense and poorly characterized side effects associated with CW treatment, identification of patients most likely to benefit from this therapy could be clinically relevant.

Summary

CWs may represent an effective and safe first-line treatment for patients with HGG that exhibit complete tumor resection and harboring a methylated MGMT promoter. Our investigation showed a much larger group of patients exhibiting long-term survival (>?=?36 months), strongly supporting a potential survival benefit conferred via CW treatment. The pre-surgical definition of the MGMT promoter status could be of clinical use in identifying “good responders” to CW implantation.
  相似文献   
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