241 research outputs found
Endobronchial Metastasis with Bloody Sputum 20 Years after Complete Resection of type A Non-Invasive Thymoma
Masaoka stage I type A thymomas rarely recur. We report the case of an 82-year-old man who developed endobronchial metastasis after thymothymectomy for Masaoka stage I type A thymoma. Twenty years after surgery, the patient developed bloody sputum, and chest computed tomography revealed a neoplasm obstructing the right upper lobe bronchus of the lung with enlarged mediastinal lymph nodes. He underwent right upper lobectomy and mediastinal lymph node dissection. Although preoperative pathological diagnosis was squamous cell carcinoma of the lung, postoperative histopathology revealed endobronchial metastasis of the thymoma. Nine years later, at age 89, the patient is alive and well
Reconstruction of Anterior Chest Wall with Polypropylene Mesh: Two Primary Sternal Chondrosarcoma Cases
 Primary sternal chondrosarcoma is a rare malignant tumor that is refractory to chemotherapy and radiation. Effective therapy is radical resection of the tumor. We present two patients with primary sternal chondrosarcoma who underwent a radical resection of the lower half of the sternum and bilateral ribs, followed by reconstruction with 2 sheets of polypropylene mesh layered orthogonally. The patients have maintained almost the same pulmonary function as preoperative values, with stability of the chest wall. Although there are various ways to reconstruct the anterior chest wall, reconstruction with polypropylene mesh layered orthogonally is an easy-to-use and sufficient method
Lung transplantation for Kartagener syndrome: technical aspects and morphological adaptation of the transplanted lungs
While technical considerations in lung transplantation for Kartagener syndrome have been discussed, little information is available about the postoperative morphological changes of the grafted lungs. Herein, we discuss both the technical aspects and postoperative morphological adaptation of the grafted lungs in a case of Kartagener syndrome. A 46-year-old male patient with Kartagener syndrome underwent bilateral cadaveric lung transplantation. The right arterial anastomosis for transplantation of the size-matched grafts required technical elaboration. After the transplantation, we found a free space in the cardiac notch of the left lung and partial collapse of the lower lobe of the right lung due to dextrocardia. Follow-up computed tomography performed on day 42 after the transplantation demonstrated resolution of the atelectasis and morphological adaptation of the grafts into the recipient’s chest cavity with dextrocardia. Considering such early morphological adaptation of size-matched grafts, lobar reduction could be avoided in lung transplantation for Kartagener syndrome
Dynamics of Quasi-ordered Structure in a Regio-regulated pi-Conjugated Polymer:Poly(4-methylthiazole-2,5-diyl)
Dynamics of regio-regulated Poly(4-methylthiazole-2,5-diyl) [HH-P4MeTz] was
inves tigated by solid-state 1H, 2D, 13C NMR spectroscopies, and differential
scanning calorimetry(DSC) measurements. DSC, 2D quadrupolar echo NMR, 13C
cross-polarization and magic-angle spinning(CPMAS) NMR, and 2D spin-echo(2DSE)
CPMAS NMR spectroscopy suggest existence of a quasi-ordered phase in which
backbone twists take place with weakened pi-stackings. Two-dimensional exchange
2D NMR(2DEX) detected slow dynamics with a rate of an order of 10^2Hz for the
CD_3 group in d_3-HH-P4MeTz at 288K. The frequency dependence of proton
longitudinal relaxation rate at 288K shows a omega^-1/2 dependence, which is
due to the one-dimensional diffusion-like motion of backbone conformational
modulation waves. The diffusion rate was estimated as 3+/-2 GHz, which was
approximately 10^7 times larger than that estimated by 2DEX NMR measurements.
These results suggest that there exists anomalous dispersion of modulation
waves in HH-P4MeTz. The one-dimensional group velocity of the wave packet is
responsible for the behavior of proton longitudinal relaxation time. On the
other hand, the 2DEX NMR is sensitive to phase velocity of the nutation of
methyl groups that is associated with backbone twists. From proton T_1 and T_2
measurements, the activation energy was estimated as 2.9 and 3.4 kcal/mol,
respectively. These were in agreement with 3.0 kcal/mol determined by
Moller-Plesset(MP2) molecular orbital(MO) calculation. We also performed
chemical shielding calculation of the methyl-carbon in order to understand
chemical shift tensor behavior, leading to the fact that a quasi-ordered phase
coexist with the crystalline phase.Comment: 14 pages, 11 figures, to appear in Phys.Rev.
Lack of kainic acid-induced gamma oscillations predicts subsequent CA1 excitotoxic cell death
Gamma oscillations are a prominent feature of hippocampal network activity, but their functional role remains debated, ranging from mere epiphenomena to being crucial for information processing. Similarly, persistent gamma oscillations sometimes appear prior to epileptic discharges in patients with mesial temporal sclerosis. However, the significance of this activity in hippocampal excitotoxicity is unclear. We assessed the relationship between kainic acid (KA)-induced gamma oscillations and excitotoxicity in genetically engineered mice in which N-methyl-d-aspartic acid receptor deletion was confined to CA3 pyramidal cells. Mutants showed reduced CA3 pyramidal cell firing and augmented sharp wave–ripple activity, resulting in higher susceptibility to KA-induced seizures, and leading to strikingly selective neurodegeneration in the CA1 subfield. Interestingly, the increase in KA-induced γ-aminobutyric acid (GABA) levels, and the persistent 30–50-Hz gamma oscillations, both of which were observed in control mice prior to the first seizure discharge, were abolished in the mutants. Consequently, on subsequent days, mutants manifested prolonged epileptiform activity and massive neurodegeneration of CA1 cells, including local GABAergic neurons. Remarkably, pretreatment with the potassium channel blocker α-dendrotoxin increased GABA levels, restored gamma oscillations, and prevented CA1 degeneration in the mutants. These results demonstrate that the emergence of low-frequency gamma oscillations predicts increased resistance to KA-induced excitotoxicity, raising the possibility that gamma oscillations may have potential prognostic value in the treatment of epilepsy.National Institutes of Health (U.S.). Intramural Research ProgramNational Institutes of Health (U.S.) (Grant R01-MH078821)Japan Society for the Promotion of Scienc
Critical Scale-invariance in Healthy Human Heart Rate
We demonstrate the robust scale-invariance in the probability density
function (PDF) of detrended healthy human heart rate increments, which is
preserved not only in a quiescent condition, but also in a dynamic state where
the mean level of heart rate is dramatically changing. This scale-independent
and fractal structure is markedly different from the scale-dependent PDF
evolution observed in a turbulent-like, cascade heart rate model. These results
strongly support the view that healthy human heart rate is controlled to
converge continually to a critical state.Comment: 9 pages, 3 figures. Phys. Rev. Lett., to appear (2004
Seroepidemiologic Studies of Hepatitis C Virus Infection in a Population of Okayama Prefecture Screened for Liver Disease
To better understand the spread of hepatitis C virus (HCV) infection, we studied the association of HCV infection with similarly transmissible hepatitis B virus (HBV) infection and with hepatitis A virus (HAV) infection, which is supposed to be related to a nosocomial transmission of HCV. This was done by studying the presence or absence of antibodies to these viruses, as well as hepatitis B surface antigen, in a population of 1,398 inhabitants with abnormal liver function tests or history of liver disease and/or blood transfusion. This group was drawn from a group of 7,905 examinees screened for liver disease in 26 districts of Okayama prefecture, Japan. The prevalence of antibody-positive cases increased with age for those viruses. Small but significantly increased odds ratios were obtained among anti-HCV antibodies (HCVAb), anti-hepatitis B core antibodies (HBcAb) and anti-hepatitis A antibodies (HAVAb). After adjusting odds ratios by logistic regression analysis, a significant association was present only between HCVAb and HBcAb. The distribution of age-adjusted prevalences (AAP) of HCVAb in 26 districts was significantly wider than those of HBcAb or HAVAb. The district-based AAP of HCVAb, but not of HBcAb and HAVAb, correlated significantly with the district-based prevalence of infectious hepatitis having a tendency of chronicity reported in 1953-1955. Adjusted odds ratios calculated by logistic regression analysis of the virus markers showed that HCVAb was significantly associated with a past history of blood transfusion. Thus, the spread of HCV infection is speculated to have been triggered by blood transfusion, particularly from paid donors initially, followed by transmission by nosocomial or close person-to-person contact.</p
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