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The dynamic structure factorS(Q,E), whereQandEare momentum and energy transfer, respectively, has been measured for liquid Eu8Ga16Ge30(EGG), using inelastic x-ray scattering. The excitation energy of the longitudinal acoustic mode in the liquid was scaled to that in liquid Ba8Ga16Sn30(BGS) with the effective mass. This result means that the local structure in both liquids are similar. The longitudinal acoustic excitation energy of type-I clathrate compound EGG disperses faster than that in the liquid, suggesting that the interatomic force is weakened on melting. The lower energy excitation was observed in both liquid EGG and liquid BGS. In comparison with the longitudinal phonon dispersion in crystalline clathrate compound EGG obtained by density functional theory-based calculations, the lower energy in the liquid was found to be near the optical mode energy. The result indicates that the lower energy mode arises from the relative motion between Eu and (Ga, Ge) atoms.
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Interactions between nematic fluctuations, magnetic order and superconductivity are central to the physics of iron-based superconductors. Here we report on in-plane transverse acoustic phonons in hole-doped Sr_{1-x}Na_{x}Fe_{2}As_{2} measured via inelastic x-ray scattering, and extract both the nematic susceptibility and the nematic correlation length. By a self-contained method of analysis, for the underdoped (x=0.36) sample, which harbors a magnetically ordered tetragonal phase, we find it hosts a short nematic correlation length ξâ¼10 Å and a large nematic susceptibility χ_{nem}. The optimal-doped (x=0.55) sample exhibits weaker phonon softening effects, indicative of both reduced ξ and χ_{nem}. Our results suggest short-range nematic fluctuations may favor superconductivity, placing emphasis on the nematic correlation length for understanding the iron-based superconductors.
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Plant genomes remain highly fragmented and are often characterized by hundreds to thousands of assembly gaps. Here, we report chromosome-level reference and phased genome assembly of Ophiorrhiza pumila, a camptothecin-producing medicinal plant, through an ordered multi-scaffolding and experimental validation approach. With 21 assembly gaps and a contig N50 of 18.49 Mb, Ophiorrhiza genome is one of the most complete plant genomes assembled to date. We also report 273 nitrogen-containing metabolites, including diverse monoterpene indole alkaloids (MIAs). A comparative genomics approach identifies strictosidine biogenesis as the origin of MIA evolution. The emergence of strictosidine biosynthesis-catalyzing enzymes precede downstream enzymes' evolution post γ whole-genome triplication, which occurred approximately 110 Mya in O. pumila, and before the whole-genome duplication in Camptotheca acuminata identified here. Combining comparative genome analysis, multi-omics analysis, and metabolic gene-cluster analysis, we propose a working model for MIA evolution, and a pangenome for MIA biosynthesis, which will help in establishing a sustainable supply of camptothecin.
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Camptotecina/biosíntesis , Evolución Molecular , Genoma de Planta/genética , Proteínas de Plantas/genética , Rubiaceae/metabolismo , Vías Biosintéticas/genética , Cromosomas de las Plantas/genética , Mapeo Contig , Genómica , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Plantas Medicinales/genética , Plantas Medicinales/metabolismo , Rubiaceae/genética , Alcaloides de la Vinca/biosíntesisRESUMEN
Biological membranes exhibit a great deal of compositional and phase heterogeneity due to hundreds of chemically distinct components. As a result, phase separation processes in cell membranes are extremely difficult to study, especially at the molecular level. It is currently believed that the lateral membrane heterogeneity and the formation of domains, or rafts, are driven by lipid-lipid and lipid-protein interactions. Nevertheless, the underlying mechanisms regulating membrane heterogeneity remain poorly understood. In the present work, we combine inelastic X-ray scattering with molecular dynamics simulations to provide direct evidence for the existence of strongly coupled transient lipid pairs. These lipid pairs manifest themselves experimentally through optical vibrational (a.k.a. phononic) modes observed in binary (1,2-dipalmitoyl-sn-glycero-3-phosphocholine [DPPC]-cholesterol) and ternary (DPPC-1,2-dioleoyl-sn-glycero-3-phosphocholine/1-palmitoyl-2-oleoyl-glycero-3-phosphocholine [DOPC/POPC]-cholesterol) systems. The existence of a phononic gap in these vibrational modes is a direct result of the finite size of patches formed by these lipid pairs. The observation of lipid pairs provides a spatial (subnanometer) and temporal (subnanosecond) window into the lipid-lipid interactions in complex mixtures of saturated/unsaturated lipids and cholesterol. Our findings represent a step toward understanding the lateral organization and dynamics of membrane domains using a well-validated probe with a high spatial and temporal resolution.
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Membrana Celular/química , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Lípidos de la Membrana/química , Membrana Celular/metabolismo , Fenómenos Químicos , Colesterol/química , FononesRESUMEN
BACKGROUND: Myanmar is one of the hotspots of biodiversity and is a rapidly developing country. Performing floristic research in Myanmar is an urgent issue, and ethnobotanical studies of wild edible plants (WEPs) will provide new information on natural plant resources. METHOD: Ethnobotanical data were collected in three villages with different historical backgrounds in Southern Shan State, Myanmar. A total of 19 key informants were interviewed, and specimens were collected in the fields with the participation of key informants in June-July 2015. Group discussions were organized during 2016 and 2017 to reinforce the information on use of WEPs. DNA barcoding was used to facilitate species identification. RESULTS: A total of 83 species from 44 families of angiosperms were recorded as WEPs. Most of the species were used as wild vegetables (47 species), followed by fruits and nuts (31 species). Eighteen WEPs were consumed as medicinal foods. Differences in use of WEPs between the communities of the villages were observed. The age class of 30-39 years was more familiar with the environments where they could collect WEPs and had more knowledge of WEPs than did the older groups. The use of Elaeocarpus floribundus as an edible oil is a very interesting tradition. CONCLUSION: WEPs play an important role in the livelihood of local communities. The indigenous society has maintained traditional knowledge of the WEPs. Historical background, land use system and surrounding vegetation could have effects on the variation in the traditional uses of WEPs. Increasing awareness of the importance of WEPs will encourage the conservation of traditional knowledge of indigenous populations.
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Conocimiento , Fitoterapia , Plantas Comestibles , Plantas Medicinales , Adulto , Biodiversidad , Conservación de los Recursos Naturales , Etnobotánica , Humanos , Persona de Mediana Edad , MianmarRESUMEN
We investigated transverse acoustic (TA) phonons in iron-bearing magnesium oxide (ferropericlase) up to 56 GPa using inelastic x-ray scattering (IXS). The results show that the energy of the TA phonon far from the Brillouin zone center suddenly increases with increasing pressure above the spin transition pressure of ferropericlase. Ab initio calculations revealed that the TA phonon energy far from the Brillouin zone center is higher in the low-spin state than in the high spin state; that the TA phonon energy depend weakly on pressure; and that the energy gap between the TA and the lowest-energy-optic phonons is much narrower in the low-spin state than in the high-spin state. This allows us to conclude that the anomalous behavior of the TA mode in the present experiments is the result of gap narrowing due to the spin transition and explains contradictory results in previous experimental studies.
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Chinese liquorice/licorice (Glycyrrhiza uralensis) is a leguminous plant species whose roots and rhizomes have been widely used as a herbal medicine and natural sweetener. Whole-genome sequencing is essential for gene discovery studies and molecular breeding in liquorice. Here, we report a draft assembly of the approximately 379-Mb whole-genome sequence of strain 308-19 of G. uralensis; this assembly contains 34 445 predicted protein-coding genes. Comparative analyses suggested well-conserved genomic components and collinearity of gene loci (synteny) between the genome of liquorice and those of other legumes such as Medicago and chickpea. We observed that three genes involved in isoflavonoid biosynthesis, namely, 2-hydroxyisoflavanone synthase (CYP93C), 2,7,4'-trihydroxyisoflavanone 4'-O-methyltransferase/isoflavone 4'-O-methyltransferase (HI4OMT) and isoflavone-7-O-methyltransferase (7-IOMT) formed a cluster on the scaffold of the liquorice genome and showed conserved microsynteny with Medicago and chickpea. Based on the liquorice genome annotation, we predicted genes in the P450 and UDP-dependent glycosyltransferase (UGT) superfamilies, some of which are involved in triterpenoid saponin biosynthesis, and characterised their gene expression with the reference genome sequence. The genome sequencing and its annotations provide an essential resource for liquorice improvement through molecular breeding and the discovery of useful genes for engineering bioactive components through synthetic biology approaches.
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Genoma de Planta , Glycyrrhiza uralensis/genética , Proteínas de Plantas/genética , Cicer/genética , Sistema Enzimático del Citocromo P-450/genética , Flavonoides/biosíntesis , Flavonoides/genética , Glucuronosiltransferasa/genética , Glucuronosiltransferasa/metabolismo , Ácido Glicirrínico/metabolismo , Medicago truncatula/genética , Metiltransferasas/genética , Metiltransferasas/metabolismo , Anotación de Secuencia Molecular , Proteínas de Plantas/metabolismo , Plantas Medicinales/genéticaRESUMEN
Seismological observations show that, in some regions of the lower mantle, an increase in bulk sound velocity, interestingly, occurs in the same volume where there is a decrease in shear velocity. We show that this anti-correlated behavior occurs on cation substitution in bridgmanite by making single crystal elasticity measurements of MgSiO3 and (Mg,Fe,Al)(Si,Al)O3 using inelastic x-ray scattering in the ambient conditions. Cation substitution of ferrous iron and aluminum may explain large low shear velocity provinces in the lower mantle.
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We investigated hydrated antifreeze protein type III (AFP III) powder with a hydration level h (=mass of water/mass of protein) of 0.4 in the temperature range between 180 K and 298 K using X-ray diffraction and inelastic X-ray scattering (IXS). The X-ray diffraction data showed smooth, largely monotonic changes between 180 K and 298 K without freezing water. Meanwhile, the collective dynamics observed by IXS showed a strong change in the sound velocity at 180 K, after being largely temperature independent at higher temperatures (298-220 K). We interpret this change in terms of the dynamic transition previously discussed using other probes including THz IR absorption spectroscopy and incoherent elastic and quasi-elastic neutron scattering. This finding suggests that the dynamic transition of hydrated proteins is observable on the subpicosecond time scale as well as nano- and pico-second scales, both in collective dynamics from IXS and single particle dynamics from neutron scattering. Moreover, it is most likely that the dynamic transition of hydrated AFP III is not directly correlated with its hydration structure.
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Proteínas Anticongelantes/química , Proteínas de Peces/química , Simulación de Dinámica Molecular , Dispersión de Radiación , Temperatura , Agua/química , Difracción de Rayos X , Rayos XRESUMEN
The use of temperature-gradient analyzers for non-resonant high-resolution inelastic X-ray scattering is investigated. The gradient compensates for geometrical broadening of the energy resolution by adjusting the lattice spacing of the analyzer crystal. Applying a â¼ 12 mK temperature gradient across a 9.5 cm analyzer, resolutions of 0.75 (2) meV FWHM at 25.7 keV for Si(13 13 13) and 1.25(2) meV at 21.7 keV for Si(11 11 11) were measured, while retaining large (250 mm) clearance between the sample position and detector, and reasonable (9.3 mrad × 8.8 mrad) analyzer acceptance. The temperature control and stability are discussed.
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Recent studies show that the D'' layer, just above the Earth's core-mantle boundary, is composed of MgSiO3 post-perovskite and has significant lateral inhomogeneity. Here we consider the D'' diversity as related to the single-crystal elasticity of the post-perovskite phase. We measure the single-crystal elasticity of the perovskite Pbnm-CaIrO3 and post-perovskite Cmcm-CaIrO3 using inelastic X-ray scattering. These materials are structural analogues to same phases of MgSiO3. Our results show that Cmcm-CaIrO3 is much more elastically anisotropic than Pbnm-CaIrO3, which offers an explanation for the enigmatic seismic wave velocity jump at the D'' discontinuity. Considering the relation between lattice preferred orientation and seismic anisotropy in the D'' layer, we suggest that the c axis of post-perovskite MgSiO3 aligns vertically beneath the Circum-Pacific rim, and the b axis vertically beneath the Central Pacific.
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Compuestos de Calcio/química , Iridio/química , Silicatos de Magnesio/química , Óxidos/química , Anisotropía , Convección , Cristalización , Planeta Tierra , Elasticidad , Fenómenos Geológicos , Modelos Teóricos , Dispersión del Ángulo Pequeño , Difracción de Rayos XRESUMEN
PURPOSE: The objective of this in vitro study was to examine the influence of the total energy of ultraviolet-C preirradiation on the number and morphology of osteoblastic cells attached to turned or acid-etched titanium surfaces, and physicochemical properties of the surface. MATERIALS AND METHODS: Rat bone marrow-derived osteoblasts were incubated with turned or acid-etched titanium disks preirradiated with ultraviolet-C at 1 or 3 mW/cm(2), resulting in total energies of 10, 100, 250, 400, 500, 600, 750, or 1000 J/cm(2). Osteoblast attachment to the surface was evaluated using the WST-1 assay. Physicochemical changes of the titanium were evaluated by measuring water wettability and X-ray photoelectron spectroscopy analysis. RESULTS: Number of attached cells was greater on turned or acid-etched surface preirradiated with 500 or 750 J/cm(2) of 3 mW/cm(2) ultraviolet-C than on the nonirradiated surface, respectively. However, the further irradiation energy did not increase the numbers on both types of the surfaces. These phenomena were also seen on the surfaces preirradiated at different ultraviolet-C intensities. Ultraviolet-C irradiation induced superhydrophilicity on both types of surface even with the less irradiation energy. The amount of carbon on ultraviolet-C preirradiated titanium surfaces decreased gradually with an increase in the total irradiation energy. CONCLUSION: Specific ultraviolet-C energy used to irradiate turned or acid-etched surfaces increased the number of osteoblastic cells attached to each of the surface. This was canceled by overirradiation, despite maintenance of both the acquired superhydrophilicity and the accompanying reduction in carbon on each surface.
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Adhesión Celular , Osteoblastos/efectos de la radiación , Titanio/química , Rayos Ultravioleta , Animales , Células de la Médula Ósea/citología , Masculino , Microscopía Electrónica de Rastreo , Osteoblastos/citología , Espectroscopía de Fotoelectrones , Ratas , Ratas Sprague-Dawley , Propiedades de Superficie , HumectabilidadRESUMEN
The phytoalexin response of Lotus japonicus seedlings to selected microbes and chemical signals was analyzed. The symbiotic rhizobium induced vestitol production weakly, while non-symbiotic rhizobia and potential pathogens led to increases in its accumulation. Whereas chitin-related molecules were ineffective, a flagellin-derived peptide not of symbiont origin induced phytoalexin production, indicating discriminative antibiotic production by the plant host.
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Lotus/metabolismo , Lotus/microbiología , Sesquiterpenos/metabolismo , Simbiosis , Flagelina/química , Flagelina/metabolismo , Regulación de la Expresión Génica de las Plantas , Lotus/genética , Fijación del Nitrógeno/genética , Proteínas de Plantas/genética , Rhizobium/genética , Rhizobium/metabolismo , Plantones/genética , FitoalexinasRESUMEN
The tetraethylammonium salt of the transition-metal complex FeCl4(-) has been examined using inelastic X-ray scattering (IXS) with 1.5 meV resolution (12 cm(-1)) at 21.747 keV. This sample serves as a feasibility test for more elaborate transition-metal complexes. The IXS spectra were compared with previously recorded IR, Raman, and nuclear resonant vibrational spectroscopy (NRVS) spectra, revealing the same normal modes but with less strict selection rules. Calculations with a previously derived Urey-Bradley force field were used to simulate the expected Q and orientation dependence of the IXS intensities. The relative merits of IXS, compared to other photon-based vibrational spectroscopies such as NRVS, Raman, and IR, are discussed.
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Complejos de Coordinación/química , Análisis Espectral , Elementos de Transición/química , Cloruros/química , Compuestos Férricos/química , Espectrometría Raman , Vibración , Rayos XRESUMEN
Heterohybridomas, created to secrete monoclonal antibodies, are generally unstable over long-term culture because of chromosome elimination during culture. To evaluate the karyotype of heterohybridomas, we used simultaneous genomic in situ hybridization (GISH), which can distinguish unambiguously between parental genomes in allopolyploid species. Using GISH, we discriminated gerbil and mouse chromosomes in heterohybridomas with high sensitivity. The GISH technique will allow evaluation of the stability and crossability of heterohybridomas made from the fusion of mouse cells with those of related species.
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Cromosomas , Genoma/genética , Gerbillinae , Hibridomas , Hibridación in Situ/métodos , Cariotipo , Hibridación de Ácido Nucleico/métodos , Animales , Fusión Celular , Células Cultivadas , Sondas de ADN , Femenino , Ratones , Sensibilidad y EspecificidadRESUMEN
High-resolution inelastic X-ray scattering (IXS) measurements were performed for room-temperature ionic liquids (ILs) of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide and bis(fluorosulfonyl)amide, [C2mIm(+)][TFSA(-)] and [C2mIm(+)][FSA(-)], respectively, at ambient temperature. The observed spectra as a function of Q of 1.4-6 nm(-1) can be ascribed to quasi-elastic and inelastic scatterings, so that they are well represented with the fitting by using the Lorentz and the damped harmonic oscillator model functions to yield the dynamic structure factors. It was found in the intermediate scattering function, F(Q, t) that both ILs show the relaxation at t < 10 ps. The IXS measurements were also made on [C2mIm(+)][TFSA(-)] and [C2mIm(+)][FSA(-)] solutions dissolving Li salt. It is suggested that the adding of Li salt to IL significantly prolongs the relaxation time.
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BACKGROUND: Diffuse alveolar hemorrhage (DAH) of unknown cause has been characterized as idiopathic pulmonary hemosiderosis (IPH). IPH is a rare disease, which has a high prevalence in children and shows a poor prognosis. However, in adults, since there are few reports about collective cases, the details remain to be determined. METHODS: Between January 2003 and June 2008, consecutive adult patients strictly defined as unknown cause DAH by chest images, fiberoptic bronchoscopy, autoantibody testing, and exclusion of systemic disease were enrolled. We investigated the clinical characterization and course of the enrolled patients. RESULTS: Nine patients were included. All patients were middle-aged men (56.1 ± 4.2 year-old) with sudden onset. They did not present with anemia (the hemoglobin level was 13.9 ± 0.5 g/dL) despite the quantity of bleeding. In bronchoalveolar-lavage fluid analysis, the cell count was increased (7.6 ± 1.6×10(5) cells/mL) with neutorophilia (33.3 ± 13.3%). The illness resolved within 2 weeks with or without corticosteroid therapy. All of the patients were alive without recurrence during the follow-up period (45.2 ± 6.2 months) after diagnosis. CONCLUSION: Adult IPH patients showed good prognosis. However, the present patients are clinically slightly different from the previously characterized IPH.
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Hemosiderosis/diagnóstico , Hemosiderosis/tratamiento farmacológico , Enfermedades Pulmonares/diagnóstico , Enfermedades Pulmonares/tratamiento farmacológico , Corticoesteroides/uso terapéutico , Adulto , Factores de Edad , Anciano , Estudios de Seguimiento , Hemosiderosis/sangre , Humanos , Enfermedades Pulmonares/sangre , Masculino , Persona de Mediana Edad , Pronóstico , Hemosiderosis PulmonarRESUMEN
Shionone is the major triterpenoid component of Aster tataricus possessing a unique all six-membered tetracyclic skeleton and 3-oxo-4-monomethyl structure. To clarify its biosynthetic process, an oxidosqualene cyclase cDNA was isolated from A. tataricus, and the function of the enzyme was determined in lanosterol synthase-deficient yeast. The cyclase yielded ca. 90% shionone and small amounts of ß-amyrin, friedelin, dammara-20,24-dienol, and 4-epishionone and was designated as a shionone synthase (SHS). Transcripts of SHS were detected in A. tataricus organs, confirming its involvement in shionone biosynthesis. SHS was shown to have evolved in the Asteraceae from ß-amyrin synthase lineages and acquired characteristic species- and product-specificities.
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Aster/enzimología , Transferasas Intramoleculares/metabolismo , Triterpenos/metabolismo , Secuencia de Aminoácidos , Aster/genética , Clonación Molecular , Evolución Molecular , Regulación de la Expresión Génica de las Plantas , Humanos , Transferasas Intramoleculares/química , Transferasas Intramoleculares/genética , Datos de Secuencia Molecular , FilogeniaRESUMEN
Polemonium kiushianum is a critically endangered species of which only eight populations exist in semi-natural grasslands of the Mt. Aso area of Kyushu, Japan. Habitat modification and the risk of hybridization with non-indigenous horticultural congeners, such as P. caeruleum subsp. caeruleum and P. caeruleum subsp. yezoense var. yezoense, pose increasing threats to P. kiushianum. To develop a DNA marker that distinguishes P. kiushianum from other Polemonium species, we performed random amplified polymorphic DNA (RAPD) analysis and selected an approximately 500-bp fragment generated by the OPB06 RAPD primer. In addition, we designed a primer pair, H11F/R, based on the nucleotide sequences of the fragments derived from P. caeruleum subsp. caeruleum and P. caeruleum subsp. yezoense var. yezoense. The results with the H11F/R primers indicated that most extant P. kiushianum plants in natural populations are not genetically contaminated by hybridization with non-indigenous horticultural species.
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Especies en Peligro de Extinción , Hibridación Genética , Magnoliopsida/genética , Técnica del ADN Polimorfo Amplificado Aleatorio/métodos , ADN de Plantas/genética , Japón , Datos de Secuencia Molecular , Especificidad de la EspecieRESUMEN
A 22-year-old man was admitted to our hospital with fever, cough and dyspnea. His chest radiograph showed diffuse ground-glass attenuation in both lung fields. Arterial blood gas analysis showed hypoxemia (PaO2 28.7 Torr breathing room air) and he required mechanical ventilation within 6 hours after admission. Gomori methenamine silver (GMS) stain of the bronchoalveolar lavage (BAL) fluid smear showed round and indented organisms, and polymerase chain reaction revealed pneumocystis jirovecii in the BAL fluid. The HIV antibody was positive and peripheral blood CD4-positive lymphocytes decreased to 4.0%. Pneumocystis pneumonia complicated with acquired immunodeficiency syndrome (AIDS) was diagnosed. There was no four-fold rise in screen viral titers. We treated him with antibiotics, trimethoprim-sulfamethoxazole, ganciclovir, fos-fluconazole, steroid pulse therapy and sivelestat sodium hydrate. Respiratory failure was relieved within 5 days following treatment. The percentage of neutrophils in the BAL fluid was elevated (44.6%). Neutrophil elastase on admission was increased and improved to the normal range after treatment. Sivelestat sodium hydrate is an anti-neutrophil elastase inhibitor and may be one of the treatment options for acute respiratory failure due to pneumocystis pneumonia in AIDS patients.