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1.
Nat Commun ; 15(1): 778, 2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38278803

ABSTRACT

Organic matter in extraterrestrial samples is a complex material that might have played an important role in the delivery of prebiotic molecules to the early Earth. We report here on the identification of nitrogen-containing compounds such as amino acids and N-heterocycles within the recent observed meteorite fall Winchcombe by high-spatial resolution spectroscopy techniques. Although nitrogen contents of Winchcombe organic matter are low (N/C ~ 1-3%), we were able to detect the presence of these compounds using a low-noise direct electron detector. These biologically relevant molecules have therefore been tentatively found within a fresh, minimally processed meteorite sample by high spatial resolution techniques conserving the overall petrographic context. Carbon functional chemistry investigations show that sizes of aromatic domains are small and that abundances of carboxylic functional groups are low. Our observations demonstrate that Winchcombe represents an important addition to the collection of carbonaceous chondrites and still preserves pristine extraterrestrial organic matter.

2.
Sci Total Environ ; 905: 167232, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-37734608

ABSTRACT

Sorption of organic molecules on mineral surfaces can occur through several binding mechanisms of varying strength. Here, we investigated the importance of inner-sphere P-O-Fe bonds in synthetic and natural mineral-organic associations. Natural organic matter such as water extracted soil organic matter (WESOM) and extracellular polymeric substances (EPS) from liquid bacterial cultures were adsorbed to goethite and examined by FTIR spectroscopy and P K-edge NEXAFS spectroscopy. Natural particles from a Bg soil horizon (Gleysol) were subjected to X-ray fluorescence (XRF) mapping, NanoSIMS imaging, and NEXAFS spectro-microscopy at the P K-edge. Inner-sphere P-O-Fe bonds were identified for both, adsorbed EPS extracts and adsorbed WESOMs. Characteristic infrared peaks for P-O-Fe stretching vibrations are present but cannot unambiguously be interpreted due to possible interferences with mono- and polysaccharides. For the Bg horizon, P was only found on Fe oxides, covering the entire surface at different concentrations, but not on clay minerals. Linear combination fitting of NEXAFS spectra indicates that this adsorbed P is mainly a mixture of orthophosphate and organic P compounds. By combining atomic force microscopy (AFM) images with STXM-generated C and Fe distribution maps, we show that the Fe oxide surfaces were fully coated with organic matter. In contrast, clay minerals revealed a much lower C signal. The C NEXAFS spectra taken on the Fe oxides had a substantial contribution of carboxylic C, aliphatic C, and O-alkyl C, which is a composition clearly different from pure adsorbed EPS or aromatic-rich lignin-derived compounds. Our data show that inner-sphere P-O-Fe bonds are important for the association of Fe oxides with soil organic matter. In the Bg horizon, carboxyl groups and orthophosphate compete with the organic P compounds for adsorption sites.

3.
Sci Rep ; 10(1): 20251, 2020 11 20.
Article in English | MEDLINE | ID: mdl-33219224

ABSTRACT

We report on the detection of primordial organic matter within the carbonaceous chondrite Maribo that is distinct from the majority of organics found in extraterrestrial samples. We have applied high-spatial resolution techniques to obtain C-N isotopic compositions, chemical, and structural information of this material. The organic matter is depleted in 15N relative to the terrestrial value at around δ15N ~ -200‰, close to compositions in the local interstellar medium. Morphological investigations by electron microscopy revealed that the material consists of µm- to sub-µm-sized diffuse particles dispersed within the meteorite matrix. Electron energy loss and synchrotron X-ray absorption near-edge structure spectroscopies show that the carbon functional chemistry is dominated by aromatic and C=O bonding environments similar to primordial organics from other carbonaceous chondrites. The nitrogen functional chemistry is characterized by C-N double and triple bonding environments distinct from what is usually found in 15N-enriched organics from aqueously altered carbonaceous chondrites. Our investigations demonstrate that Maribo represents one of the least altered CM chondrite breccias found to date and contains primordial organic matter, probably originating in the interstellar medium.

4.
Environ Sci Pollut Res Int ; 25(36): 36645-36660, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30377963

ABSTRACT

Zinc incorporation into marine bivalve shells belonging to different genera (Donax, Glycymeris, Lentidium, and Chamelea) grown in mine-polluted seabed sediments (Zn up to 1% w/w) was investigated using x-ray diffraction (XRD), chemical analysis, soft x-ray microscopy combined with low-energy x-ray fluorescence (XRF) mapping, x-ray absorption spectroscopy (XAS), and transmission electron microscopy (TEM). These bivalves grew their shells, producing aragonite as the main biomineral and they were able to incorporate up to 2.0-80 mg/kg of Zn, 5.4-60 mg/kg of Fe and 0.5-4.5 mg/kg of Mn. X-ray absorption near edge structure (XANES) analysis revealed that for all the investigated genera, Zn occurred as independent Zn mineral phases, i.e., it was not incorporated or adsorbed into the aragonitic lattice. Overall, our results indicated that Zn coordination environment depends on the amount of incorporated Zn. Zn phosphate was the most abundant species in Donax and Lentidium genera, whereas, Chamelea shells, characterized by the highest Zn concentrations, showed the prevalence of Zn-cysteine species (up to 56% of total speciation). Other Zn coordination species found in the investigated samples were Zn hydrate carbonate (hydrozincite) and Zn phosphate. On the basis of the coordination environments, it was deduced that bivalves have developed different biogeochemical mechanisms to regulate Zn content and its chemical speciation and that cysteine plays an important role as an active part of detoxification mechanism. This work represents a step forward for understanding bivalve biomineralization and its significance for environmental monitoring and paleoreconstruction.


Subject(s)
Animal Shells/chemistry , Bivalvia/chemistry , Environmental Monitoring/methods , Geologic Sediments/chemistry , Mining , Water Pollutants, Chemical/analysis , Zinc/analysis , Animals , Italy , Phosphates/analysis , Zinc Compounds/analysis
5.
Nanomaterials (Basel) ; 7(10)2017 Oct 16.
Article in English | MEDLINE | ID: mdl-29035310

ABSTRACT

Gold nanorods (GNRs) have been fabricated by a novel polymer-immobilised seed mediated method using ultraviolet (UV) photoreduced gold-polymethylmethacrylate (Au-PMMA) nanocomposites as a seed platform and characterised at sub-micron scale regime with synchrotron-based techniques; near-edge X-ray absorption fine structure (NEXAFS) spectroscopy and X-ray fluorescence (XRF) mapping. In this report, it is shown that investigating polymer nanocomposites using combination of XRF mapping and NEXAFS spectromicroscopy can help to see the growth phenomenon from different perspective than conventional characterisation techniques. XRF maps are used to explore distribution of the constituent elements and showing how polymer matrix making stripe patterns along with regions where GNRs are formed. NEXAFS carbon (C) K-edge spectra have been taken at three different stages of synthesis: (1) on Au-PMMA nanocomposites before UV irradiation, (2) after gold nanoparticles formation, and (3) after GNRs formation. It reveals how polymer matrix has been degraded during GNRs formation and avoiding chemically or physically damage to polymer matrix is crucial to control the formation of GNRs.

6.
Int J Urol ; 24(8): 626-631, 2017 08.
Article in English | MEDLINE | ID: mdl-28627033

ABSTRACT

OBJECTIVES: To determine the efficacy of two α1-adrenoceptor antagonists with different affinities for α1-adrenoceptor subtypes, silodosin and naftopidil, in the treatment of premature ejaculation. METHODS: This was a prospective, open-label, multicenter trial. A total of 26 patients with untreated acquired premature ejaculation were enrolled. Premature ejaculation was defined based on the International Society for Sexual Medicine recommendation. Patients self-administered on demand silodosin 4 mg or naftopidil 25 mg 1 h before intercourse, alternating drugs at least three times each. Clinical global impression change for premature ejaculation, premature ejaculation profile, and intravaginal ejaculation latency time were evaluated at baseline and during treatment. RESULTS: Due to clinical global impression change, 24 patients (92%) and 12 patients (46%) reported improvement in their own premature ejaculation problems under silodosin and nafitopidil administration, respectively. Silodosin treatment produced a significantly higher improvement rate compared with naftopidil (P = 0.0002). Objectively, silodosin significantly prolonged intravaginal ejaculation latency time compared with baseline and naftopidil (P < 0.01). Mean intravaginal ejaculation latency times were 1.9, 4.1, and 7.6 min at baseline, control and with silodosin, respectively. The rate of reduced semen volume during silodosin treatment was higher than during naftopidil treatment. There were no adverse systemic effects in either group. CONCLUSIONS: Silodosin, a highly selective α1A-adrenoceptor antagonist, produces greater improvements in premature ejaculation profiles and related symptoms along with intravaginal ejaculation latency time in acquired premature ejaculation patients with or without erectile dysfunction. This result supports the clinical use of silodosin as an alternative treatment for premature ejaculation.


Subject(s)
Adrenergic alpha-1 Receptor Antagonists/therapeutic use , Indoles/therapeutic use , Naphthalenes/therapeutic use , Piperazines/therapeutic use , Premature Ejaculation/drug therapy , Urological Agents/therapeutic use , Adult , Aged , Humans , Male , Middle Aged , Prospective Studies , Self Administration , Time Factors , Treatment Outcome , Young Adult
7.
J Infect Chemother ; 23(8): 512-516, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28476331

ABSTRACT

OBJECTIVES: Sexually transmitted infections due to Chlamydia trachomatis (C. trachomatis) are a worldwide public health problem. The aim of this study was to investigate the drug susceptibilities of C. trachomatis strains isolated from the urethra and pharynx of Japanese males. METHODS: Urethral and pharyngeal swabs were collected between 2013 and 2014 from Japanese males with urethritis. Using a McCoy cell line, 18 chlamydial strains were isolated from urethra in 18 patients and 7 from the pharynx in 7 of the 18 patients. The minimum inhibitory concentrations (MICs) of levofloxacin (LVFX) and azithromycin (AZM) were measured using the standard method of the Japanese Society of Chemotherapy. RESULTS: The MICs of LVFX and AZM against urethral chlamydial strains were 0.125-0.5 µg/mL and 0.125-0.25 µg/mL, respectively. In pharyngeal strains, the MICs of LVFX and AZM were 0.125-0.25 µg/mL and 0.125-0.25 µg/mL, respectively. In 7 patients with chlamydial strains isolated from both the urethra and pharynx, the MICs of LVFX between these strains were identical in 3 of 6 patients (no growth was observed for one pharyngeal strain), while the MICs of AZM between these strains were identical in all 6 patients (not performed for one patient). CONCLUSIONS: Our data suggest that C. trachomatis strains isolated from the urethra and pharynx of Japanese males are susceptible to LVFX and AZM. Although measuring the MICs of chlamydial strains is labor intensive, it is a significant surveillance tool for treating chlamydial infections and preventing the spread of STIs.


Subject(s)
Anti-Bacterial Agents/pharmacology , Chlamydia Infections/microbiology , Chlamydia trachomatis/drug effects , Pharynx/microbiology , Urethra/microbiology , Adolescent , Adult , Chlamydia Infections/epidemiology , Drug Resistance, Bacterial , HeLa Cells , Humans , Japan/epidemiology , Male , Microbial Sensitivity Tests , Young Adult
8.
Acta Med Okayama ; 67(4): 245-51, 2013.
Article in English | MEDLINE | ID: mdl-23970323

ABSTRACT

A crossover study was conducted to identify the best α1-adrenoceptor (α1AR) antagonist for individual patients with lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). One hundred thirteen patients (mean age 70.8 years) were enrolled. All patients met BPH clinical study guidelines. Seven agents were utilized:tamsulosin 0.2mg, silodosin 8mg, urapidil 60mg, naftopidil 50mg, prazosin 1mg, terazosin 2mg, and doxazosin 1mg. Patients were initially prescribed tamsulosin or silodosin for a week and then urapidil for a week. Two weeks later, they were prescribed the better of the 2 agents for a week and a new agent for the next week. This cycle was repeated until all 7 agents were tested. Efficacy was evaluated with the International Prostate Symptom Score. The agent rankings were doxazosin (25 [22%]), silodosin (22 [19%]), urapidil (19 [17%]), naftopidil (17 [15%]), terazosin (12 [11%]), tamsulosin (11 [10%]), prazosin (7 [6%]). Only 12 patients (11%) changed agents after the crossover study was completed. The major reason was adverse events (83%). We found that each of the 7 α1AR antagonists has its own supporters. Further, the one-week crossover study was useful in identifying the best agent for the treatment of each individual with LUTS.


Subject(s)
Adrenergic alpha-1 Receptor Antagonists/administration & dosage , Lower Urinary Tract Symptoms/drug therapy , Lower Urinary Tract Symptoms/etiology , Prostatic Hyperplasia/complications , Sulfonamides/administration & dosage , Adrenergic alpha-1 Receptor Antagonists/adverse effects , Adult , Aged , Aged, 80 and over , Cross-Over Studies , Doxazosin/administration & dosage , Doxazosin/adverse effects , Humans , Indoles/administration & dosage , Indoles/adverse effects , Male , Middle Aged , Naphthalenes/administration & dosage , Naphthalenes/adverse effects , Piperazines/administration & dosage , Piperazines/adverse effects , Prazosin/administration & dosage , Prazosin/adverse effects , Prazosin/analogs & derivatives , Sulfonamides/adverse effects , Tamsulosin , Treatment Outcome
9.
J Magn Reson Imaging ; 37(5): 1168-77, 2013 May.
Article in English | MEDLINE | ID: mdl-23165993

ABSTRACT

PURPOSE: To investigate the feasibility of targeted biopsy based on an apparent diffusion coefficient (ADC) map in the detection and localization of prostate cancer. MATERIALS AND METHODS: This study included 288 consecutive patients with high or increasing serum prostate-specific antigen (PSA) levels who underwent prostatic magnetic resonance imaging (MRI) examination with an ADC map. Four core-targeted biopsies of low ADC lesions were performed under transrectal-ultrasound guidance with reference to ADC map. The positive predictive values (PPVs) of low ADC lesions were calculated and compared for the peripheral zone (PZ), transition zone (TZ), and anterior portion, respectively. Comparisons of ADC values and sizes between malignant and nonmalignant lesions were also performed. RESULTS: A total of 313 low ADC lesions were detected in 195 patients and sampled by targeted biopsies. The PPVs were 55.3% (95% confidence interval [CI]: 50-61) in total, 61.0% (95% CI: 53-69) for PZ, 50.6% (95% CI: 43-58) for TZ, and 90.9% (95% CI: 81-100) for the anterior portion. The most common nonmalignant pathology of low ADC lesions was hyperplasia, followed by chronic prostatitis. There were significant differences in ADC values and sizes between malignant and nonmalignant low ADC lesions. CONCLUSION: Targeted biopsies could be capable of detecting cancers well wherever they may be in the prostate, although the PPVs varied depending on the location of low ADC lesions.


Subject(s)
Algorithms , Biopsy, Large-Core Needle/methods , Image Interpretation, Computer-Assisted/methods , Image-Guided Biopsy/methods , Magnetic Resonance Imaging, Interventional/methods , Pattern Recognition, Automated/methods , Prostatic Neoplasms/pathology , Aged , Aged, 80 and over , Feasibility Studies , Humans , Image Enhancement/methods , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity
10.
J Infect Chemother ; 18(5): 729-33, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22491994

ABSTRACT

Pharyngeal chlamydial and gonococcal infections can occur as a consequence of oral sex, and they also can be transmitted from the pharynx to the genital tract of sex partners. There have been many reports on the prevalence of pharyngeal Chlamydia trachomatis and Neisseria gonorrhoeae in men who have sex with men; however, there have been few reports on the prevalence of these pathogens in the pharynges of heterosexual men. In this study, we determined the prevalence of pharyngeal C. trachomatis and N. gonorrhoeae in 42 heterosexual men diagnosed with urethritis. Pharyngeal swabs and first-voided urine specimens were tested using the Gen-Probe APTIMA Combo 2 transcription-mediated amplification assay. The prevalence of pharyngeal C. trachomatis and N. gonorrhoeae in patients with urethritis was 2.4 % (1/42) and 11.9 % (5/42), respectively. Among patients with either chlamydial or gonococcal urethritis, 9.1 % (1/11) and 25.0 % (5/20) had pharyngeal C. trachomatis or N. gonorrhoeae, respectively. Our results suggest that screening for pharyngeal colonization by N. gonorrhoeae and C. trachomatis using validated nucleic acid amplification tests should be performed in heterosexual men diagnosed with urethritis.


Subject(s)
Chlamydia Infections/epidemiology , Chlamydia trachomatis/isolation & purification , Gonorrhea/epidemiology , Neisseria gonorrhoeae/isolation & purification , Pharyngeal Diseases/epidemiology , Adolescent , Adult , Chlamydia Infections/microbiology , Chlamydia trachomatis/genetics , DNA, Bacterial/analysis , DNA, Bacterial/genetics , Gonorrhea/microbiology , Heterosexuality/statistics & numerical data , Humans , Japan/epidemiology , Male , Middle Aged , Neisseria gonorrhoeae/genetics , Pharyngeal Diseases/microbiology , Pharynx/microbiology , Prevalence , Sexual Behavior , Urethra/microbiology , Urethritis/complications , Urethritis/epidemiology
11.
J Magn Reson Imaging ; 35(6): 1414-21, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22246980

ABSTRACT

PURPOSE: To investigate the usefulness of targeted biopsy strategy based on apparent diffusion coefficient (ADC) maps in the detection and localization of prostate cancer. MATERIALS AND METHODS: Institutional review board approval and informed consent from all participants were obtained. This study included 1448 consecutive patients suspected of having prostate cancer based on PSA level, who were divided into two groups: Group A included 890 patients with low-ADC lesions who underwent targeted and systematic biopsies; Group B included 558 patients with no low-ADC lesions who underwent only systematic biopsies. The cancer detection rates (CDR) of each group, positive predictive value (PPV), and negative predictive value (NPV) of ADC maps were calculated. RESULTS: The CDR was 70.1% for Group A, higher than those for overall patients (48.1%) and for Group B (13.1%) with significant difference (P < 0.001). In the serum, PSA range from 4 to 20 ng/mL, the CDR was higher for the Group A than for the Group B and overall patients with significant differences. PPV and NPV of MR findings were 70.1% and 86.9%, respectively. Especially, the PPV of the MR findings for the anterior portion was as high as 90.1%. Among the false negatives of MR findings, Gleason score proved 6 or smaller in 79.5%, and positive core number was merely one or two in 80.8%. CONCLUSION: The targeted biopsy strategy based on ADC maps can be useful in the detection and localization of prostate cancer with high PPV.


Subject(s)
Biopsy, Needle/methods , Biopsy, Needle/statistics & numerical data , Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Imaging, Interventional/methods , Magnetic Resonance Imaging, Interventional/statistics & numerical data , Prostatic Neoplasms/epidemiology , Prostatic Neoplasms/pathology , Aged , Cohort Studies , Humans , Image Enhancement/methods , Japan/epidemiology , Male , Prevalence , Prospective Studies , Reproducibility of Results , Sensitivity and Specificity
12.
Jpn J Radiol ; 29(7): 488-94, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21882091

ABSTRACT

PURPOSE: The aim of this study was to determine the cutoff level of apparent diffusion coefficient (ADC) values for diagnosing prostate cancer. MATERIALS AND METHODS: A total of 45 consecutive patients with prostate cancer who underwent diffusion-weighted magnetic resonance imaging (MRI) with ADC maps before radical prostatectomy were included in this retrospective study. MRI findings were correlated retrospectively with histopathological results of surgical specimens. Comparisons of ADC values between cancer and noncancer areas were performed with the two-tailed unequal variance t-test. The cutoff ADC level was determined in a way to achieve the best accuracy for detecting prostate cancer. RESULTS: The mean ADC value of all the cancer lesions (n =60) was 1.04 ± 0.31 (×10(-3) mm(2)/s). In the peripheral zone, the mean ADC values of cancer lesions and noncancer areas were 1.07 ± 0.35 and 1.94 ± 0.31, respectively (P < 0.001). In the transition zone, the mean ADC values of cancer lesions and noncancer areas were 1.00 ± 0.22 and 1.56 ± 0.14, respectively (P<0.001). The cutoff level for the ADC value was determined to be 1.35×10(-3) mm(2)/s. It provided sensitivity, specificity, and accuracy of 88%, 96%, and 93%, respectively. CONCLUSION: The cutoff ADC level determined on the basis of the results obtained from radical prostatectomy specimens can help differentiate malignant from nonmalignant lesions.


Subject(s)
Diffusion Magnetic Resonance Imaging/methods , Prostatic Neoplasms/pathology , Aged , Biopsy , Humans , Male , Middle Aged , Neoplasm Staging , Prostatectomy , Prostatic Neoplasms/surgery , Retrospective Studies , Sensitivity and Specificity
13.
Langmuir ; 25(5): 2588-92, 2009 Mar 03.
Article in English | MEDLINE | ID: mdl-19437683

ABSTRACT

Lightly cross-linked sterically stabilized poly(2-vinylpyridine) latexes exhibit pH-responsive behavior, undergoing a latex-to-microgel transition below pH 4.1 as a result of protonation of the pyridine pendent groups. We have examined both the latex and microgel states of such particles directly in aqueous solution using scanning transmission X-ray microscopy (STXM). Moreover, near-edge X-ray absorption fine structure (NEXAFS) spectroscopy studies confirm that the nitrogen atoms of the microgel particles are fully protonated at low pH. The addition of salt causes partial deswelling of these microgel particles, but spectroscopic analysis confirms the retention of their cationic character. This is the first direct visualization of the effect of electrolyte screening on microgel dimensions in aqueous solution. In each case, the observed particle dimensions are consistent with dynamic light scattering characterization, especially when polydispersity effects are taken into consideration.

14.
Acta Med Okayama ; 62(6): 373-8, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19122682

ABSTRACT

We previously reported the effectiveness of loxoprofen sodium (loxoprofen), a non-steroidal anti-inflammatory drug, for patients with lower urinary tract symptoms (LUTS) complaining of nocturia. In this study, we explored the mechanism of loxoprofen in the treatment of nocturia. Fifty-six patients complaining of nocturia were enrolled. They took a single 60-mg tablet of loxoprofen at bedtime for 14 days. The effects of this treatment were assessed by bladder diaries. Nocturia improved (nocturia decreased >or=1 void/night) in 40 patients (71.4%). Nocturnal urine volume was reduced in 31 of 40 (77.5%) without nocturnal single-void volume increase. Nocturnal single-void volume increased in 4 of 40 (10.0%) without nocturnal urine volume reduction. Two of 40 (5.0%) demonstrated both nocturnal urine volume reduction and nocturnal single-void volume increase. Three (7.5%) were exceptions to the above. In conclusion, the main mechanism of loxoprofen is the reduction of nocturnal urine volume for the treatment of nocturia and the second mechanism is the increased bladder capacity.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Nocturia/drug therapy , Nocturia/physiopathology , Phenylpropionates/administration & dosage , Aged , Aged, 80 and over , Female , Humans , Male , Medical Records , Middle Aged , Treatment Outcome , Urine
15.
Science ; 314(5806): 1711-6, 2006 Dec 15.
Article in English | MEDLINE | ID: mdl-17170289

ABSTRACT

The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. The preliminary examination of these samples shows that the nonvolatile portion of the comet is an unequilibrated assortment of materials that have both presolar and solar system origin. The comet contains an abundance of silicate grains that are much larger than predictions of interstellar grain models, and many of these are high-temperature minerals that appear to have formed in the inner regions of the solar nebula. Their presence in a comet proves that the formation of the solar system included mixing on the grandest scales.

16.
Science ; 314(5806): 1720-4, 2006 Dec 15.
Article in English | MEDLINE | ID: mdl-17170291

ABSTRACT

Organics found in comet 81P/Wild 2 samples show a heterogeneous and unequilibrated distribution in abundance and composition. Some organics are similar, but not identical, to those in interplanetary dust particles and carbonaceous meteorites. A class of aromatic-poor organic material is also present. The organics are rich in oxygen and nitrogen compared with meteoritic organics. Aromatic compounds are present, but the samples tend to be relatively poorer in aromatics than are meteorites and interplanetary dust particles. The presence of deuterium and nitrogen-15 excesses suggest that some organics have an interstellar/protostellar heritage. Although the variable extent of modification of these materials by impact capture is not yet fully constrained, a diverse suite of organic compounds is present and identifiable within the returned samples.


Subject(s)
Meteoroids , Organic Chemicals/analysis , Carbon/analysis , Cosmic Dust/analysis , Deuterium/analysis , Nitrogen/analysis , Nitrogen Isotopes/analysis , Oxygen/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Spacecraft
17.
Hinyokika Kiyo ; 52(8): 609-14, 2006 Aug.
Article in Japanese | MEDLINE | ID: mdl-16972622

ABSTRACT

A total of 4,031 patients who underwent transurethral resection of the prostate (TURP) performed by one surgeon between May 1979 and December 2003 were retrospectively examined to determine the improvement of the surgeon's skill in performing TURP assessed by using a learning curve, surgical results and postoperative complications. Analysis using the learning curve, which displayed the relationship between the number of TURP procedures and the speed of resection (i.e., the weight of tissue resected divided by the operation time), revealed that 81 operations were needed before the surgeon's skill reached a plateau in performing TURP. The means +/- standard deviations of the weight of tissue resected, operation time and speed of resection were 17.0 +/- 14.6 g, 21.0 +/- 13.5 minutes, 0.80 +/- 0.32 g/minutes, respectively. As the number of TURP procedures increased and the level of skill improved, the operation time was significantly reduced and the speed of resection was significantly increased. The incidences of postoperative complications were 2.4% for blood transfusion, 0.3% for the TURP syndrome, 1.5% for hemostatic procedures, 2.8% for bladder neck contracture, and 1.0% for urethral stricture. The incidences of transfusion and the TURP syndrome decreased as the surgeon's skill improved. The mortality rate was 0.1%.


Subject(s)
Transurethral Resection of Prostate , Aged , Aged, 80 and over , Clinical Competence , Humans , Male , Middle Aged , Postoperative Complications , Prostatic Hyperplasia/surgery , Retrospective Studies , Time Factors , Transurethral Resection of Prostate/mortality , Transurethral Resection of Prostate/standards , Treatment Outcome
18.
Environ Sci Technol ; 40(5): 1556-65, 2006 Mar 01.
Article in English | MEDLINE | ID: mdl-16568770

ABSTRACT

A scanning transmission X-ray microscope illuminated with synchrotron light was used to investigate the speciation and spatial distributions of metals in a microbial biofilm cultivated from river water. Metal 2p absorption edge signals were used to provide metal speciation (through shapes of the absorption spectra) and quantitative spatial distributions of the metal species. This paper presents sample data and describes methods for extracting quantitative maps of metal species from image sequences recorded in the region of the metal 2p edges. Comparisons were made with biochemical characterization of the same region using images recorded at the C 1s and O 1s edges. The method is applied to detailed quantitative analysis of ferrous and ferric iron in a river biofilm, in concert with mapping Ni(II) and Mn(II) species in the same region. The distributions of the metal species are discussed in the context of the biofilm structure. These results demonstrate that soft X-ray STXM measurements at the metal 2p absorption edges can be used to speciate metals and to provide quantitative spatial distribution maps for metal species in environmental samples with 50 nm spatial resolution.


Subject(s)
Manganese/chemistry , Microscopy/methods , Nickel/chemistry , Biofilms , X-Rays
19.
J Am Chem Soc ; 127(48): 16808-9, 2005 Dec 07.
Article in English | MEDLINE | ID: mdl-16316226

ABSTRACT

Scanning transmission X-ray microscopy has been employed to visualize pH-responsive acid-swellable microgel particles directly in their swollen state in aqueous acidic solution. Moreover, NEXAFS studies confirm that the nitrogen atoms of these cationic microgel particles are completely protonated at low pH.

20.
J Biomater Sci Polym Ed ; 16(5): 611-27, 2005.
Article in English | MEDLINE | ID: mdl-16001720

ABSTRACT

Alginate microcapsules enclosing recombinant cells secreting therapeutic products have been used successfully to treat several murine models of human diseases. The mechanical and chemical properties of these alginate capsules can be improved by the addition and in situ photo-polymerization of sodium acrylate and N-vinylpyrrolidone in the alginate capsule. The purpose of this modification was to form additional covalent cross-links. In this work we have used scanning transmission X-ray microscopy (STXM) to probe the nature and location of the chemical modifications in the modified capsules by comparison with unmodified capsules. Analysis of X-ray image sequences and selected area spectra has been used to map the calcium gradient in capsules, to identify the presence of polyacrylate throughout the capsules and the localization of poly-N-vinylpyrrolidone in the outer regions of the alginate capsules. The differences in the spatial distributions of these species have led to better understanding of the chemical modifications that provide a mechanically more stable capsule structure.


Subject(s)
Acrylates/chemistry , Alginates/chemistry , Calcium Chloride/chemistry , Capsules/chemistry , Cross-Linking Reagents/chemistry , Pyrrolidinones/chemistry , Electron Probe Microanalysis , Glucuronic Acid/chemistry , Hexuronic Acids/chemistry
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