Spin-Orbit Effects on Exciton Complexes in Diamond.

Ultrafine splittings are found in the optical absorption spectra of boron-doped diamond measured with high resolution. An analytical model of an exciton complex is developed, which permits assigning all absorption lines and sizing the interactions among the constituent charges and crystal field. We conclude that the entry of split-off holes in the acceptor-bound exciton fine structure yields two triplets separated by a spin-orbit splitting of 14.3 meV. Our findings thereby resolve a long-standing controversy [R. Sauer et al., Revised fine splitting of excitons in diamond, Phys. Rev. Lett. 84, 4172 (2000).PRLTAO0031-900710.1103/PhysRevLett.84.4172; M. Cardona et al., Comment on "Revised fine splitting of excitons in diamond,", Phys. Rev. Lett. 86, 3923 (2001).PRLTAO0031-900710.1103/PhysRevLett.86.3923; R. Sauer and K. Thonke, Sauer and Thonke reply, Phys. Rev. Lett. 86, 3924 (2001).PRLTAO0031-900710.1103/PhysRevLett.86.3924], revealing the underlying physics common in diverse semiconductors, including diamond.

Caffeine poisoning successfully treated by venoarterial extracorporeal membrane oxygenation and emergency hemodialysis.

BACKGROUND: Caffeine overdose can cause life-threatening circulatory failure, neurological abnormalities, and ventricular fibrillation. We report the case of a patient with caffeine poisoning who was successfully treated with early hemodialysis and venoarterial extracorporeal membrane oxygenation. CASE PRESENTATION: A 43-year-old man who had ingested pills containing 20 g caffeine was transported to the hospital 100 min after ingestion. Hemodynamic collapse and refractory arrhythmia were most likely the potential complications. The patient developed ventricular fibrillation when placed in the left lateral decubitus position. Return of spontaneous circulation with defibrillation and introduction of venoarterial extracorporeal membrane oxygenation were followed by emergency dialysis, which led to rapid improvement in the clinical findings. CONCLUSION: Acute caffeine poisoning in a patient who developed an arrhythmia was successfully treated using an indwelling arterial and venous sheath followed by venoarterial extracorporeal membrane oxygenation.

Risk of stroke and heart failure attributable to atrial fibrillation in middle-aged and elderly people: Results from a five-year prospective cohort study of Japanese community dwellers.

BACKGROUND: The relative and absolute risks of stroke and heart failure attributable to atrial fibrillation (AF) have not been sufficiently examined. METHODS: A prospective study of 23,731 community-dwelling Japanese individuals was conducted. Participants were divided into two groups based on the presence or absence of prevalent AF (n = 338 and n = 23,393, respectively). Excess events (EE) due to AF and relative risks (RRs) determined using the non-AF group as the reference for incident stroke and heart failure were estimated using Poisson regression stratified by age groups (middle-aged: 40-69 years old; elderly: 70 years of age or older) after adjustment for sex and age. RESULTS: There were 611 cases of stroke and 98 cases of heart failure during the observation period (131,088 person-years). AF contributed to a higher risk of stroke both in middle-aged individuals (EE 10.4 per 1000 person-years; RR 4.88; 95% confidence interval [CI], 2.88-8.29) and elderly individuals (EE 18.3 per 1000 person-years; RR 3.05; 95% CI, 2.05-4.54). AF also contributed to a higher risk of heart failure in middle-aged individuals (EE 3.7 per 1000 person-years; RR 8.18; 95% CI, 2.41-27.8) and elderly individuals (EE 15.4 per 1000 person-years; RR 7.82; 95% CI, 4.11-14.9). Results obtained from multivariate-adjusted analysis were similar (stroke: EE 8.9 per 1000 person-years; RR 4.40; 95% CI, 2.57-7.55 in middle-aged and EE 17.4 per 1000 person-years; RR 2.97; 95% CI, 1.99-4.43 in elderly individuals; heart failure: EE 3.1 per 1000 person-years; RR 7.22; 95% CI, 2.06-25.3 in middle-aged and EE 14.1 per 1000 person-years; RR 7.41; 95% CI, 3.86-14.2 in elderly individuals). CONCLUSIONS: AF increased the risk of stroke by the same magnitude as that reported previously in Western countries. AF increased the RR of heart failure more than that in Western populations.

Lymphangiogenic factors are associated with the severity of hypersensitivity pneumonitis.

BACKGROUND: Antigen presenting cells play a pivotal role in the adaptive immune response in hypersensitivity pneumonitis (HP). It was hypothesised that lymphangiogenesis is involved in the pathophysiology of HP via cell transport. OBJECTIVE: To determine the clinical significance of lymphangiogenic factors in HP. METHODS: Levels of vascular endothelial growth factors (VEGF)-A, VEGF-C, VEGF-D and CCL21 in the serum and bronchoalveolar lavage fluid (BALF) were measured in 29 healthy volunteers, 14 patients with idiopathic pulmonary fibrosis (IPF) and 26 patients with HP by ELISA. Additionally, immunohistochemical analyses were performed using lung specimens of patients with HP (n=8) and IPF (n=10). RESULTS: BALF VEGF-D levels were significantly elevated in patients with HP compared to the other groups. BALF VEGF-D levels in patients with HP correlated significantly with the BALF total cell and lymphocyte counts (r=0.485, p=0.014 and r=0.717, p<0.0001, respectively). BALF VEGF-C and CCL21 levels were increased in patients with HP compared to healthy volunteers, but not patients with IPF. BALF CCL21 levels were negatively correlated with the forced expiratory volume in 1 s percentage and diffuse capacity of the lung for carbon monoxide (r=-0.662, p=0.007 and r=-0.671, p=0.024, respectively). According to the immunohistochemical analyses, CCL21 was expressed in the lymphatic endothelium in both conditions and CCR7(+) cells were aggregated around lymphatics in patients with HP, but not in patients with IPF. CONCLUSIONS: Lymphangiogenic factors might be associated with the inflammatory and functional severity of HP. The increased BALF VEGF-D levels were associated with lymphatic alveolitis intensity, and CCL21 with lung function impairment.