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51.
52.
Postoperative atrial fibrillation (POAF), the most frequent arrhythmia after pulmonary resection, is a cause of both morbidity and mortality. Being able to predict the risk of POAF before surgery would help us evaluate the surgical risk and plan prophylaxis. We investigated the reported preoperative risk factors associated with the incidence of POAF and found that the recommended predictive factors were quite variable. Therefore, we evaluated the previously reported preoperative risk factors for POAF using our institutional data. We discuss our findings in this short review. Male gender, resected lung volume, brain natriuretic peptide (BNP), and left ventricular early transmitral velocity/mitral annular early diastolic velocity (E/e′) calculated by echocardiography were suggested as independent predictors for POAF, but the predictive values of each individual parameter were not high. The lack of definitive predictors for POAF warrants further investigations by gathering the reported knowledge, to establish an effective preoperative examination strategy.  相似文献   
53.

Purpose

Cerebral infarction is a rare complication of lung resection that can result in severe sequelae. Our aim was to investigate the characteristics of patients who suffer from cerebral infarction after surgery for lung cancer.

Methods

We retrospectively reviewed all patients who underwent resection of at least a single lobe for lung cancer at our institution between January 2008 and October 2013. We compared the patients who presented with cerebral infarction with those patients who did not within 30 days of surgery.

Results

A total of 562 patients underwent surgery, with five males and one female subsequently experiencing cerebral infarction. Five patients underwent left upper lobectomy and one underwent left lower lobectomy. Patient age, sex, body mass index, smoking index, and operative time were not significantly different between the six patients with postoperative cerebral infarction and the other 556 patients; only the type of operative procedure was significantly different (p < 0.001). Contrast-enhanced computed tomography revealed thrombosis in the stump of the left superior pulmonary vein in patients with postoperative cerebral infarction.

Conclusions

Cerebral infarction occurs at a high frequency in patients who undergo left upper lobectomy for lung cancer. Thrombosis in the left superior pulmonary-vein stump might cause cerebral infarction.
  相似文献   
54.
Tumor-specific peptide-pulsed dendritic cells (DC) were administered via different routes to a group of patients with head and neck cancers. The migration and homing patterns of such antigen-stimulated cells was carefully studied employing single photon emission computed tomography (SPECT). The DC administered directly into the nasal submucosa quickly migrated very rapidly to the regional neck lymph nodes in the neck. However, after inoculation of the cells into the palatine tonsils, the DCs remained close to the site of administration and did not migrate to the regional lymph nodes or to other mucosal regions. After nasal submucosal administration of the DC, tumor-antigen-specific cytotoxic T cells were detected in the ipsilaterals but not in the contra lateral lymph nodes. These results suggest that after antigen processing, the regional lymph nodes serve as inductive sites for development of mucosal immune responses and for induction of memory cells during the local immunological responses in the nasopharyngeal-associated lymphoid tissue in man.  相似文献   
55.

Purposes

The purpose of this study was to investigate the compensatory phenomena after lung resection in clinical cases by evaluating the spirometric and radiological parameters.

Methods

Forty patients undergoing lobectomy for stage IA lung cancer were divided into the following groups: (A) patients with <10 (n = 20) and (B) patients with ≥10 resected subsegments (n = 20). Comparisons were made of the predicted and observed postoperative values of spirometry and radiological parameters, such as lung volumetry and the “estimated lung weight”. Predicted values were based on the number of resected subsegments. The postoperative time to re-evaluation was at least 1 year for both groups.

Results

The predicted postoperative values of spirometry underestimated the actual values, and the differences were more significant in group B (forced vital capacity, p = 0.006, forced expiratory volume in 1 s, p = 0.011). Focusing on the remnant lungs on the surgical side, group B had significantly larger % postoperative lung volumes (161 ± 6.0 %) and % estimated lung weight (124 ± 5.4 %) than did group A (114 ± 3.8 %, p < 0.0001; 89.5 ± 4.4 %, p < 0.0001, respectively).

Conclusions

Major lung resection in clinical cases causes a compensatory restoration of the pulmonary function and tissue.  相似文献   
56.
Immunoglobulin A class antibody to hepatitis C virus core antigen (IgA anti-HCc) was measured in the serum of 128 patients with type C chronic liver disease. Fifty-eight patients (45.3%) were seropositive. IgA anti-HCc was detected in only one of 20 patients with chronic persistent hepatitis; however, 52.3% (46/88) of patients with chronic active hepatitis and 55% (11/20) of patients with liver cirrhosis were seropositive. Histological examination revealed that 22 (71.0%) of 31 patients with severe disease activity were seropositive compared to 35 (44.9%) of 78 patients with moderate (P<0.05) and one (5.3%) of 19 patients with mild (P<0.01) histological changes. IgA anti-HCc was measured sequentially in 65 patients who underwent interferon therapy. There was a significant difference between responders and other patients in the mean ratio of IgA anti-HCc titers one month after therapy. Three months after therapy, IgA anti-HCc was detectable in only two of 15 responders who were IgA anti-HCc seropositive at the start of therapy. In contrast, IgA anti-HCc reappeared three months after therapy despite a temporary decrease to undetectable levels in all nonresponders. We conclude that IgA anti-HCc is a useful marker to identify the presence of active type C liver disease and that the disappearance of IgA anti-HCc three months after interferon therapy predicts a good response in treated patients.  相似文献   
57.
We have characterized immunoglobulin switch circular DNA in mice infected with the nematode parasite Nippostrongylus brasiliensis. Two kinds of circular DNA were identified in the lymph nodes as excision products of switch recombination of immunoglobulin heavy-chain constant region (CH) genes. One is a recombinant between C mu and C gamma 1 (gamma 1 circle), and the other is a recombinant between C gamma 1 and C epsilon (epsilon circle). In the epsilon circle, a short piece of switch mu (S mu) sequence was inserted between S epsilon and S gamma 1 sequences. The inserted S mu sequence could be a trace of the preceding switch from C mu to C gamma 1. These findings indicate that parasitic infection can induce class switch recombinations in a successive manner, first from C mu to C gamma 1, and then from C gamma 1 to C epsilon.  相似文献   
58.
We have investigated expression of an IgE-binding factor (IgE-BF) cDNA in both COS-7 monkey kidney cells and Chinese hamster ovary cells. Transient expression of the IgE-BF clone in either cell type yielded IgE-BF, which potentiated an in vitro IgE response and had an affinity for lentil lectin. In contrast, when the transient expression experiments were carried out in the presence of tunicamycin, the factors no longer bound to lentil lectin. Moreover, IgE-BF expressed under these conditions suppressed an in vitro IgE response. IgE-BF lacking affinity for lentil lectin and suppressing the IgE response also resulted from transient expression of the IgE-BF gene in the presence of glycosylation inhibiting factor, a phospholipase inhibitory protein. Thus, IgE-BF that either potentiate or suppress the IgE response can be expressed from a single cloned gene; the difference in biological activities appears to be determined principally by the type of glycosylation of the common polypeptide chain. Previous work showed that IgE-BF bears an antigenic determinant recognized by the anti-Ia monoclonal antibody OX3. IgE-BF produced in the presence of tunicamycin, and IgE-BF expressed from a mutant cDNA lacking one of two carbohydrate-attachment sites, lacked the OX3 determinant. Thus, the OX3 determinant on IgE-BF appears to be associated with a site of N-linked glycosylation.  相似文献   
59.
Effects of recombinant human interleukins on hematopoiesis were explored by using suspension cultures of mononuclear cells of human umbilical-cord blood and bone marrow. The results showed that interleukin 5 induced the selective differentiation and proliferation of eosinophils. After 3 weeks in culture with interleukin 5, essentially all nonadherent cells in both bone marrow and cord blood cell cultures became eosinophilic myelocytes. Culture of the same cells with interleukin 4 resulted in the selective growth of OKT3+ lymphocytes. However, OKT3+ cells did not develop if the bone marrow cells were depleted of OKT3+/OKT11+ cells prior to the culture, indicating that interleukin 4 induced the proliferation of a subpopulation of resting T cells present in cord blood and bone marrow cell preparations. In suspension cultures of bone marrow cells and cord blood cells grown in the presence of interleukin 3, basophilic, eosinophilic, and neutrophilic myelocytes and macrophages developed within 2 weeks. By 3 weeks, however, the majority of nonadherent cells became eosinophilic myelocytes. In contrast to mouse bone marrow cell cultures, neither interleukin 3 nor a combination of interleukins 3 and 4 induced the differentiation of mast cells in human bone marrow or cord blood cell cultures.  相似文献   
60.
OBJECTIVE: To examine the performance of an interferon-gamma (IFN-gamma) release assay (QuantiFERON-TB 2G assay [QFT-G]) to detect Mycobacterium tuberculosis infection in a Japanese general hospital, for the diagnosis of active pulmonary tuberculosis (PTB) and extra-pulmonary tuberculosis (EPTB). DESIGN: We prospectively examined the performance of QFT-G in 194 patients suspected of active TB. Diagnosis was confirmed by 1) positive M. tuberculosis cultures, or 2) clinical manifestations or laboratory or pathological findings consistent with active TB and response to specific therapy. RESULTS: Three patients with indeterminate QFT-G results were excluded. Among the remaining 191 patients, 77 had active TB. When the cut-off concentration of IFN-gamma was set at 0.35 IU/ml, as recommended by the manufacturer, the assay was positive in 69 patients and negative in 122. The sensitivity of the assay was 76.6% in all patients, 74.5% in the 47 patients with PTB and 80.0% in the 30 patients with EPTB. The overall specificity of the assay was 91.2%. CONCLUSION: Although the specificity of the QFT-G to detect active TB was high and its sensitivity low, it was as accurate for the detection of active EPTB as for PTB when the 0.35 IU/ml INF-gamma cut-off concentration was used.  相似文献   
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