Quantitative T1 mapping of the substantia nigra using phase-sensitive inversion recovery sequence at 3.0-T: a healthy volunteer study.

BACKGROUND: Quantitative evaluation of degeneration of the substantia nigra (SN) is important for early, pre-symptomatic diagnosis of Parkinson's disease (PD). Accordingly, a clinically feasible imaging and quantification technique are needed. PURPOSE: To investigate the T1 value of the SN in healthy individuals from phase-sensitive inversion recovery (PSIR) images and to clarify its correlation with the SN characteristics on neuromelanin (NM) images to identify an imaging biomarker for early diagnosis of PD. MATERIAL AND METHODS: T1-weighted and NM images of the SN from 32 healthy volunteers were obtained using PSIR and turbo spin-echo sequences. The contrast between the SN and cerebral peduncle (CP) and area of the SN were measured; the T1 values of the SN from PSIR images and relationships between the T1 value and age/SN area were evaluated. RESULTS: There was a significant negative correlation between age and the SN area obtained using PSIR imaging. The SN area on PSIR images (104.9 ± 20.9 mm2) was significantly larger than that on NM images (72.1 ± 14.9 mm2). There was a significant negative correlation between the SN area and the T1 value of the SN obtained from PSIR images. CONCLUSION: In healthy adults, the area and T1 value of the SN measured on PSIR images were different from those obtained from NM images. This suggests that PSIR imaging may help in the assessment of SN degeneration.

Electronic Origin of Optically-Induced Sub-Picosecond Lattice Dynamics in MoSe2 Monolayer.

Atomically thin layers of transition metal dichalcogenide (TMDC) semiconductors exhibit outstanding electronic and optical properties, with numerous applications such as valleytronics. While unusually rapid and efficient transfer of photoexcitation energy to atomic vibrations was found in recent experiments, its electronic origin remains unknown. Here, we study the lattice dynamics induced by electronic excitation in a model TMDC monolayer, MoSe2, using nonadiabatic quantum molecular dynamics simulations. Simulation results show sub-picosecond disordering of the lattice upon photoexcitation, as measured by the Debye-Waller factor, as well as increasing disorder for higher densities of photogenerated electron-hole pairs. Detailed analysis shows that the rapid, photoinduced lattice dynamics are due to phonon-mode softening, which in turn arises from electronic Fermi surface nesting. Such mechanistic understanding can help guide optical control of material properties for functionalizing TMDC layers, enabling emerging applications such as phase change memories and neuromorphic computing.

Clinical significance of intra-alveolar fibrin deposition in transbronchial lung biopsy in patients with organizing pneumonia.

OBJECTIVE: This study examined the clinical significance of intra-alveolar fibrin deposition (IAFD) in transbronchial lung biopsy specimens obtained from patients with organizing pneumonia. METHODS: Pathological reports of transbronchial lung biopsies performed between 2004 and 2012 were reviewed to identify cases of intra-alveolar organization with or without fibrin deposition. Clinical charts, computed tomography images, and transbronchial lung biopsy specimens from these cases were examined retrospectively. Diagnosis of organizing pneumonia was reevaluated based upon the consensus of a respiratory physician, a radiologist, and a pathologist. RESULTS: Transbronchial lung biopsy results of the reviewed patients with organizing pneumonia found seven patients who had IAFD, and 34 who did not. Seven patients' conditions were associated with collagen vascular disease (CVD), and 34 were cryptogenic. IAFD was significantly associated with high C-reactive protein (CRP) values (>5 mg/dl) (p = 0.0012) and underlying CVD (p = 0.0099). Multivariate analysis revealed that IAFD was independently associated with high CRP values (p = 0.0184). Three of 31 patients and six of 27 patients experienced a relapse of organizing pneumonia within 6 months and 1 year, respectively. IAFD (p = 0.0044) and high CRP values (p = 0.0207) were significantly related to relapse within 6 months, while only CRP was significantly related to relapse within 1 year (p = 0.0007). CONCLUSION: In patients with organizing pneumonia, IAFD was significantly associated with high CRP values. High CRP values and/or IAFD predicted relapse of organizing pneumonia within 6 months to 1 year.

Quantifying physical insights cooperatively with exhaustive search for Bayesian spectroscopy of X-ray photoelectron spectra.

We analyzed the X-ray photoelectron spectra (XPS) of carbon 1s states in graphene and oxygen-intercalated graphene grown on SiC(0001) using Bayesian spectroscopy. To realize highly accurate spectral decomposition of the XPS spectra, we proposed a framework for discovering physical constraints from the absence of prior quantified physical knowledge, in which we designed the prior probabilities based on the found constraints and the physically required conditions. This suppresses the exchange of peak components during replica exchange Monte Carlo iterations and makes possible to decompose XPS in the case where a reliable structure model or a presumable number of components is not known. As a result, we have successfully decomposed XPS of one monolayer (1ML), two monolayers (2ML), and quasi-freestanding 2ML (qfs-2ML) graphene samples deposited on SiC substrates with the meV order precision of the binding energy, in which the posterior probability distributions of the binding energies were obtained distinguishably between the different components of buffer layer even though they are observed as hump and shoulder structures because of their overlapping.

Retrospective study on the efficacy of monocyte distribution width (MDW) as a screening test for COVID-19.

BACKGROUND: Pathogenic genetic testing for coronavirus disease 2019 (COVID-19) can detect viruses with high sensitivity; however, there are several challenges. In the prevention, testing, and treatment of COVID-19, more effective, safer, and convenient methods are desired. We evaluated the possibility of monocyte distribution width (MDW) as an infection biomarker in COVID-19 testing. METHODS: The efficacy of MDW as a screening test for COVID-19 was retrospectively assessed in 80 patients in the COVID-19 group and 232 patients in the non-COVID-19 group (141 patients with acute respiratory infection, 19 patients with nonrespiratory infection, one patient with a viral infection, 11 patients who had received treatment for COVID-19, one patient in contact with COVID-19 patients, and 59 patients with noninfectious disease). RESULTS: The median MDW in 80 patients in the COVID-19 group was 23.3 (17.2-33.6), and the median MDW in 232 patients in the non-COVID-19 group was 19.0 (13.6-30.2) (P < 0.001). When the COVID-19 group was identified using the MDW cut-off value of 21.3 from the non-COVID-19 group, the area under the curve (AUC) was 0.844, and the sensitivity and specificity were 81.3% and 78.2%, respectively. Comparison of MDW by severity between the COVID-19 group and patients with acute respiratory infection in the non-COVID-19 group showed that MDW was significantly higher in the COVID-19 group for all mild, moderate I, and moderate II disease. CONCLUSIONS: MDW (cut-off value: 21.3) may be used as a screening test for COVID-19 in fever outpatients. Trial registration This study was conducted after being approved by the ethics committee of National Hospital Organization Omuta National Hospital (Approval No. 3-19). This study can be accessed via https://omuta.hosp.go.jp/files/000179721.pdf .

Flare phenomenon following gefitinib treatment of lung adenocarcinoma with bone metastasis.

The skeleton is the most common site for distant metastasis in patients with cancer. To detect bone metastasis and evaluate the efficacy of treatment, we usually use bone scintigraphy and check serum alkaline phosphatase (ALP). However, such evaluation is sometimes difficult due to flare phenomenon. A 61-year-old male was referred to our department with a suspected diagnosis of lung cancer. Following thorough examinations, he was diagnosed with primary lung cancer (adenocarcinoma, Stage IV) and found to have a mutation in the epidermal growth factor receptor gene at exon 21 (L858R). After initiating treatment with oral gefitinib, ALP increased and peaked at 3,592 U/L by 3 weeks and decreased thereafter. At 4 weeks following treatment initiation, bone scintigraphy revealed a marked increase in abnormal accumulation of (99m)Tc-polyphosphate, but the primary tumor and metastases in regions other than the bone were reduced. At 9 weeks after treatment initiation, abnormal accumulations was improved in bone scintigraphy, and computed tomography revealed osteoblastic changes consistent with the accumulated lesion observed by bone scintigraphy. After initiating cancer treatment for bone metastasis, it is not uncommon to observe transient asynchronous accumulation in bone scintigraphy or transient increases in ALP in patients who ultimately respond to the treatment. These changes are called flare phenomenon, and documented in patients with prostate cancer or breast cancer receiving treatment. When determining the efficacy of treatments that target carcinomas with bone metastases, it is important to note that flare phenomenon is often indistinguishable from disease progression indicators.

Small-cell lung cancer from the peripheral lung is frequently accompanied by emphysema and interstitial lung disease in the background.

BACKGROUND: It has long been thought that small-cell lung cancer (SCLC) is a central type of tumor that is located in the proximal bronchi and the mediastinum. However, several studies reported that SCLC exhibited several types of spread pattern on computed tomography (CT). The aim of this study is to investigate the relationship between CT images and clinical characteristics in patients with SCLC. METHODS: We retrospectively reviewed the CT images of 92 SCLC patients and classified them into six types of spreading patterns: central, peripheral, lymphangitic spread (LYM), pleural dissemination (PLE), lobar replacement (LOB), and air-space consolidation (AC). We also evaluated the correlation between primary tumor location and the clinical characteristics of patients. RESULTS: The most common type of imaging pattern was peripheral (n = 40, 44%), with the next most common type being central (n = 27, 29%). Atypical types of SCLC, such as LYM (n = 2, 2%), PLE (n = 4, 4%), LOB (n = 8, 9%), and AC (n = 11, 12%), were also recognized in our study. The prevalence of emphysema and interstitial lung disease (ILD) was significantly higher in the peripheral type than in the central type (p = 0.0056 and p = 0.0403, respectively). Meanwhile, no survival difference was seen between the central type and the peripheral type (median months 17.9 vs. 21.9, respectively, p = 0.720). CONCLUSIONS: The peripheral type of tumor was correlated with higher prevalence of emphysema and ILD in SCLC. Our result suggests different mechanisms of development and tumor characteristics according to tumor location.

Efficacy of steroid pulse therapy for miliary tuberculosis complicated by acute respiratory distress syndrome.

Introduction: Acute respiratory distress syndrome (ARDS) is considered a poor prognostic factor for miliary tuberculosis (MTB), but little is known about the effectiveness of steroid pulse therapy for MTB complicated by ARDS. Patients and methods: Medical records were used to retrospectively investigate the prognosis and clinical information of 13 patients diagnosed with MTB complicated by ARDS among 68 patients diagnosed with MTB at our hospital between January 1994 and October 2016. None of the patients had multidrug resistant tuberculosis (TB). MTB was diagnosed by 1 radiologist and 2 respiratory physicians based on the observation of randomly distributed, uniformly sized diffuse bilateral nodules on chest computed tomography and the detection of mycobacterium TB from clinical specimens. ARDS was diagnosed based on the Berlin definition of ARDS. The effect of steroid pulse therapy on death within 3 months of hospitalization was examined using Cox proportional hazards models. Variables were selected by the stepwise method (variable reduction method). Results: Six of 8 patients with MTB complicated by ARDS were alive 3 months after hospitalization in the steroid pulse therapy group, whereas only 1 of 5 patients was alive in the non-steroid pulse therapy group. Analysis of factors related to the survival of patients with MTB complicated by ARDS revealed that steroid pulse therapy was the strong prognostic factor (hazard ratio = 0.136 (95 % CI: 0.023-0.815)). Conclusion: Our findings suggest that steroid pulse therapy improves the short-term prognosis of patients with MTB complicated by ARDS.

Nocardia transvalensis pulmonary infection in an immunocompetent patient with radiographic findings consistent with nontuberculous mycobacterial infections.

A chest roentgenogram of a 75-year-old immunocompetent woman showed disseminated micronodular densities in bilateral lung fields. Subsequent high-resolution computed tomography (CT) confirmed centrilobular micronodular densities associated with bronchial wall thickening and bronchiectatic changes. CT imaging also revealed volume loss with bronchiectatic changes in both the right middle lobe and the left lingular segment. Cytology specimens were then obtained through bronchial brushing and washes. Smears from right B2 and B4 revealed filamentous gram-positive, branched bacteria embedded among many neutrophils. Nocardia transvalensis was cultured from the bronchial wash, and no mycobacteria were identified. To our knowledge, this is the first report of a Nocardia transvalensis pulmonary infection in an immunocompetent patient, and also the first detailed description of a Nocardia transvalensis pulmonary infection in Japan. Moreover, the radiographic and CT findings in this patient were quite similar to those seen in patients with nontuberculous mycobacterial pulmonary infections, a pattern not previously reported in patients with Nocardia pulmonary infections.

[Clinical review of 8 patients with tuberculous peritonitis].

OBJECTIVE: With the progress of anti-tuberculous therapy, tuberculous peritonitis (TBP) has become a rare manifestation of active tuberculosis. Its early diagnosis is difficult due to lack of pathognomonic findings and specific symptoms. However, early diagnosis is important for effective treatment and for reducing fatality. MATERIALS AND METHOD: We retrospectively reviewed medical records of eight patients who were hospitalized with TBP in National Hospital Organization Omuta National Hospital during the periods between 2001 and 2009. RESULTS: Three patients were males and five were females. The age of the patients ranged between 28 and 80 years old (average 67.3 years). The most common presenting findings were abdominal distention seen in four patients and loss of appetite in five patients. Blood examination suggested that most patients were in poor nutrition. Three patients were diagnosed based on bacteriological examination, two based on histopathological findings of caseating granulomas, two based on the elevation of adenosine deaminase activity in ascitic fluid and one based on clinical diagnosis. The most common CT findings were thin lines along mesenteric vessels representing thickened mesenteric leaves and smooth uniform peritoneal thickening. Most patients were treated with isoniazid, rifampicin and ethambutol for 9 months with/without pyrazinamide initially. Seven patients completed anti-tuberculous therapy successfully and were cured. However, one patient died of the deterioration of tuberculosis. CONCLUSION: TBP should be considered for diagnosis, in patients with non-specific abdominal symptoms. Adenosine deaminase activity in ascitic fluid and CT images are considered to be useful for the diagnosis of TBP in patients in whom bacteriological and histopathological examinations are difficult to perform.

[A case of mild pulmonary tuberculosis complicated with the syndrome of inappropriate antidiuretic hormone secretion which caused impaired consciousness].

An 81-year-old woman was admitted to our hospital for hyponatremia and impaired consciousness after unsuccessful antibiotic treatment for pneumonia-like symptoms by a previous doctor. A chest X-ray film revealed unilateral infiltration. Mycobacterium tuberculosis was detected on a sputum smear and pulmonary tuberculosis was diagnosed. Based on the diagnostic criteria, we believed that her hyponatremia a consequence of syndrome of inappropriate antidiuretic hormone secretion (SIADH) as a complication of pulmonary tuberculosis. Sodium loading and water restriction quickly improved her serum sodium level and impaired consciousness. Anti-tuberculosis therapy reduced the abnormal shadows noted on chest X-ray films, and the sputum smear became negative for Mycobacterium tuberculosis. Her serum sodium level remained normal after the discontinuation of sodium loading. Previous reports have associated SIADH with severe types of tuberculosis such as miliary tuberculosis, tuberculosis meningitis, and pulmonary tuberculosis with massive bacterial excretion. However, this complication can also occur in mild tuberculosis, as in this case, thus SIADH should also be considered in mild cases of tuberculosis.

[Reversed halo sign in organizing pneumonia secondary to Sjögren syndrome].

We report a case of a 41-year-old woman admitted to our hospital for dyspnea on exertion and nonproductive cough. High-resolution computed tomography (HRCT) revealed central ground-glass opacities surrounded by ring-shaped areas of consolidation (reversed halo sign), predominantly in the lower lobes. Bronchoalveolar lavage fluid revealed an increase of the total number of cells (35 x 10(4)/ml), including elevated lymphocyte level (69%) and decreased CD4/CD8 ratio (0.45). Histopathological examination by transbronchial lung biopsy showed polypoid masses of granulation tissue filling the lumens of a respiratory bronchiole and alveolar ducts, consistent with organizing pneumonia. After admission the patient complained of dry eyes and dry mouth. The serum anti-SS-A antibody level was also elevated (65.0 U/ml). Labial salivary gland biopsy specimens revealed focal lymphocytic infiltration of more than 50 per 4 mm(2). There were no findings of rheumatoid arthritis or other collagen diseases. We diagnosed primary Sjögren syndrome with secondary organizing pneumonia with a reversed halo sign. She was treated with prednisolone (0.5 mg/kg body weight, 35 mg/day). After treatment, the chest CT showed improvement through consolidation.

Indium kinetics in an indium exposed worker before and after bilateral lung transplantation.

BACKGROUND: A male worker with indium-tin oxide (ITO)-induced pneumoconiosis underwent bilateral lung transplantation (LT). METHODS: Post-LT histopathological investigations of the isolated lungs and hilar lymph nodes were performed and indium concentration in serum (In-S) and serum Krebs von den Lungen-6 (KL-6) were tracked for 122 weeks. RESULTS: He has attained the ultimate treatment goal of > 2-year survival. The main histopathological characteristics were pan-lobular emphysematous change, interstitial fibrosis, and lymphocytic infiltration in the peribronchiolar/perivascular portions, and numerous cholesterol clefts and giant cells containing brown particles. These findings support the conclusion that the lung injury was caused by the inhalation of ITO. Metal element mapping and indium in the isolated lungs revealed that inhaled ITO particles in humans migrate to the lymph nodes. In-S remained at remarkably high levels (≥30 ng/mL) and showed wide fluctuation with bimodality until 46 weeks after LT, but KL-6 remained in the normal range for almost the entire period. The indium concentration in the donor's resection lung at 10 weeks after LT was 143.5 ng/g wet-weight, which was only one one-thousandth of the recipient's lung (161 µg/g wet-weight). After 48 weeks of LT, the recipient's In-S had gradually decreased; the biological half-life was 1.2 years. These results clearly suggest that indium remaining in the recipient's tissues did not adversely influence the transplant donor's lungs. CONCLUSIONS: The transplanted donor's lungs were not influenced by indium in the recipient's organs. Bilateral LT is thus an effective treatment option in severe indium lung disease cases.

Field-Induced Carrier Localization Transition in Dielectric Polymers.

Organic polymers offer many advantages as dielectric materials over their inorganic counterparts because of high flexibility and cost-effective processing, but their application is severely limited by breakdown in the presence of high electric fields. Dielectric breakdown is commonly understood as the result of avalanche processes such as carrier multiplication and defect generation that are triggered by field-accelerated hot carriers (electrons or holes). In stark contrast to inorganic dielectric materials, however, there remains no mechanistic understanding to enable quantitative prediction of the breakdown field in polymers. Here, we perform systematic study of different electric fields on hot carrier dynamics and resulting chemical damage in a slab of archetypal polymer, polyethylene, using nonadiabatic quantum molecular dynamics simulations. We found that high electric fields induce localized electronic states at the slab surface, with a critical transition occurring near the experimentally reported intrinsic breakdown field. This transition in turn facilitates strong polaronic coupling between charge carriers and atoms, which is manifested by severe damping of the time evolution of localized states and the presence of C-H vibrational resonance in the hot-carrier motion leading to rapid carbon-carbon bond breaking on the surface. Such polaronic localization transition may provide a critically missing prediction method for computationally screening dielectric polymers with high breakdown fields.

Tellurene Photodetector with High Gain and Wide Bandwidth.

Two-dimensional (2D) semiconductors have been extensively explored as a new class of materials with great potential. In particular, black phosphorus (BP) has been considered to be a strong candidate for applications such as high-performance infrared photodetectors. However, the scalability of BP thin film is still a challenge, and its poor stability in the air has hampered the progress of the commercialization of BP devices. Herein, we report the use of hydrothermal-synthesized and air-stable 2D tellurene nanoflakes for broadband and ultrasensitive photodetection. The tellurene nanoflakes show high hole mobilities up to 458 cm2/V·s at ambient conditions, and the tellurene photodetector presents peak extrinsic responsivity of 383 A/W, 19.2 mA/W, and 18.9 mA/W at 520 nm, 1.55 µm, and 3.39 µm light wavelength, respectively. Because of the photogating effect, high gains up to 1.9 × 103 and 3.15 × 104 are obtained at 520 nm and 3.39 µm wavelength, respectively. At the communication wavelength of 1.55 µm, the tellurene photodetector exhibits an exceptionally high anisotropic behavior, and a large bandwidth of 37 MHz is obtained. The photodetection performance at different wavelength is further supported by the corresponding quantum molecular dynamics (QMD) simulations. Our approach has demonstrated the air-stable tellurene photodetectors that fully cover the short-wave infrared band with ultrafast photoresponse.

[Two cases of intravascular lymphomatosis diagnosed by transbronchial lung biopsy].

Patient 1 was a 54-year-old woman who was admitted with high-grade fever. Abnormal laboratory findings included hypoxemia, and elevated levels of LDH and soluble interleukin-2 receptor (sIL-2R). Chest computed tomography scans (CT) revealed diffuse ground-glass shadows in both lungs. Transbronchial lung biopsy (TBLB) confirmed the diagnosis of intravascular lymphomatosis (IVL). Patient 2 was a 46-year-old man who was also admitted with high-grade fever. Abnormal laboratory findings included slight hypoxemia, and elevated levels of LDH and sIL-2R. Chest CT images revealed diffuse, fine nodular densities in both lungs and several small nodules in the bilateral lower lobes. Perfusion scintigraphy revealed multiple defects in both lungs. TBLB specimens yielded a diagnosis of IVL. Although antemortem diagnosis of IVL is frequently difficult, it is necessary to perform TBLB in those patients who show fever not responding to antibiotics, elevated levels of LDH and sIL-2R, and hypoxemia.

[A case of right paratracheal air cyst].

An 87-year-old female was being examined by her primary care doctor during a follow-up of 4 to 5 years after a diagnosis of non-tuberculous mycobacterial infection. An exacerbation of a shadow was suspected on a chest X-ray film, and therefore the patient was referred to our hospital. Her chief clinical symptom was mild occasional coughing, but no clearly abnormal findings were observed on the clinical examination. On chest CT, a cystic lesion was detected in the right posterodorsal side of the trachea at the level of the thoracic aperture, resulting in the diagnosis of a right paratracheal air cyst. Right paratracheal air cyst is a relatively rare disease, but it is believed that such a diagnosis can be made easily based on its localization and the CT findings, and it is a disease to which attention should be paid, which is why we are reporting it.

[A case of Streptomyces pneumonia].

A 85-year-old man who had a past history of gastrectomy but no subsequent chemotherapy was suffering fever and fatigue. The infiltrative shadow with cavitation on his chest X-ray film did not improve despite treatment with several antibiotics after admission. Transcutaneous needle aspiration performed for diagnosis of the cavitated lung lesion yielded Streptomyces. A definitive diagnosis of streptomyces lung infection was established. We believed that this is the first case of streptomyces infection of the lung reported in Japan. The current case was also rare because he did not have any immunosuppressive status, while almost all cases previously reported.

Hot-Carrier Dynamics and Chemistry in Dielectric Polymers.

Dielectric polymers are widely used in electronics and energy technologies, but their performance is severely limited by the electrical breakdown under a high electric field. Dielectric breakdown is commonly understood as an avalanche of processes such as carrier multiplication and defect generation that are triggered by field-accelerated hot electrons and holes. However, how these processes are initiated remains elusive. Here, nonadiabatic quantum molecular dynamics simulations reveal microscopic processes induced by hot electrons and holes in a slab of an archetypal dielectric polymer, polyethylene, under an electric field of 600 MV/m. We found that electronic-excitation energy is rapidly dissipated within tens of femtoseconds because of strong electron-phonon scattering, which is consistent with quantum-mechanical perturbation calculations. This in turn excites other electron-hole pairs to cause carrier multiplication. We also found that the key to chemical damage is localization of holes that travel to a slab surface and weaken carbon-carbon bonds on the surface. Such quantitative information can be incorporated into first-principles-informed, predictive modeling of dielectric breakdown.

Pulmonary varix mimicking arteriovenous malformation.

We report here a case of a 44-year-old female with a pulmonary varix. The patient was asymptomatic; a routine chest X-ray incidentally revealed a serpiginous mass in the left hilar region. Computed tomography revealed a serpiginous, dilated vascular structure in the left upper lobe that continued into the lower lobe and was suggestive of an arteriovenous malformation. Pulmonary angiography revealed no arterial abnormality; however, the filling of an abnormally dilated pulmonary vein was observed. Angiography is considered to be the most useful method for the confirmatory diagnosis of pulmonary varices.