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991.
BACKGROUND: The impact of HLA-specific antibodies is not well established in the acute rejection of lung allografts. Acute rejection represents the most important risk factor for the development of chronic lung allograft dysfunction. METHODS: We analyzed the pattern of HLA antibodies before and after transplantation in 54 patients, and correlated our data with the presence and frequency of high-grade and persistent-recurrent acute rejection, during the first 18 post-operative months. The diagnosis of acute rejection was based on histologic International Society for Heart and Lung Transplantation (ISHLT)-published criteria. RESULTS: Ten of 54 patients had a positive enzyme-linked immunoassay (ELISA) post-transplantation. In 90% of ELISA-positive patients, the presence of HLA antibodies was associated with persistent-recurrent acute rejections, compared with 34% in the ELISA-negative group (p < 0.005). There were 28 high-grade acute rejection episodes in the ELISA-positive group, compared with 36 in the ELISA-negative group (p < 0.0001). The ELISA-positive patients required a greater intensity of immunosuppressive therapy. The patients with ELISA-detected anti-HLA antibodies were at least 3-fold more likely to develop high-grade acute rejection and persistent-recurrent acute rejection, and 7-fold more likely to develop multiple episodes of persistent-recurrent acute rejection, compared with ELISA-negative patients. CONCLUSIONS: ELISA-based screening for the development of HLA antibodies is a reliable method that can identify lung transplant recipients at increased risk for high-grade and persistent-recurrent acute rejection. Although bronchiolitis obliterans appears as a point of no return in the evolution of lung-transplanted patients, early detection of risk factors for acute rejection could indirectly decrease the incidence of bronchiolitis obliterans. These lung-transplanted patients may benefit from an altered strategy of immunosuppression.  相似文献   
992.
Repair of patellar tendon injuries using a cell-collagen composite.   总被引:18,自引:0,他引:18  
Collagen gels were seeded with rabbit bone marrow-derived mesenchymal stem cells (MSCs) and contracted onto sutures at initial cell densities of 1, 4, and 8 million cells/ml. These MSC-collagen composites were then implanted into full thickness, full length, central defects created in the patellar tendons of the animals providing the cells. These autologous repairs were compared to natural repair of identical defects on the contralateral side. Biomechanical, histological, and morphometric analyses were performed on both repair tissue types at 6, 12, and 26 weeks after surgery. Repair tissues containing the MSC-collagen composites showed significantly higher maximum stresses and moduli than natural repair tissues at 12 and 26 weeks postsurgery. However, no significant differences were observed in any dimensional or mechanical properties of the repair tissues across seeding densities at each evaluation time. By 26 weeks, the repairs grafted with MSC-collagen composites were one-fourth of the maximum stress of the normal central portion of the patellar tendon with bone ends. The modulus and maximum stress of the repair tissues grafted with MSC-collagen composites increased at significantly faster rates than did natural repairs over time. Unexpectedly, 28% of the MSC-collagen grafted tendons formed bone in the regenerating repair site. Except for increased repair tissue volume, no significant differences in cellular organization or histological appearance were observed between the natural repairs and MSC-collagen grafted repairs. Overall, these results show that surgically implanting tissue engineered MSC-collagen composites significantly improves the biomechanical properties of tendon repair tissues, although greater MSC concentrations produced no additional significant histological or biomechanical improvement.  相似文献   
993.
Summary: We made quantitative analysis of seizure frequency 1 week and 6, 12, and 24 months after seizure surgery. Seizure recurrence was significantly higher when seizures occurred in the first postoperative week. Seizure recurrence increased progressively with longer follow-ups, but the 6 month postoperative follow-up period was an excellent index of long-term outcome. In operative follow-up studies, seizure frequency should be reported at fixed follow-up periods, e.g., at 6 months and 1, 2, 5, and 10 years. Meaningful comparison of outcomes between different studies is possible only when reports include outcome at fixed postoperative follow-up periods (as opposed to ranges of follow-up periods).  相似文献   
994.
The antibacterial activities of human regimens of cefepime, ceftazidime, and imipenem alone or in combination with amikacin against an isogenic pair of Enterobacter cloacae strains (wild type and its corresponding derepressed cephalosporinase mutant) were compared by using our nonlethal model of pneumonia with 180 immunocompetent rats. Compared with untreated animals, all β-lactam-treated rats, except those inoculated with the mutant isolate and receiving ceftazidime, had significantly lower bacterial counts in their lungs 60 h after the onset of therapy. Although the combination of a β-lactam and amikacin was more bactericidal than each corresponding antimicrobial agent alone, true synergy was noted only with cefepime and imipenem against the constitutive derepressed strain.  相似文献   
995.
996.
Premenstrual syndrome (PMS) encompasses a variety of symptoms appearing during the luteal phase of the menstrual cycle. Although PMS is widely recognized, the etiology remains unclear and it lacks definitive, universally accepted diagnostic criteria. To address these issues an international multidisciplinary group of experts evaluated the current definitions and diagnostic criteria of PMS and premenstrual dysphoric disorder (PMDD). Following extensive correspondence, a consensus meeting was held with the aim of producing updated diagnostic criteria for PMS and guidelines for clinical and research applications. This report presents the conclusions and recommendations of the group. It is hoped that the criteria proposed by the group will become widely accepted and eventually be incorporated into the next edition of the World Health Organization's International Classification of Diseases (ICD-11). It is also hoped that the proposed guidelines for quantification of criteria will be used by clinicians and investigators to facilitate diagnostic uniformity in the field as well as adequate treatment modalities when warranted.  相似文献   
997.
BACKGROUND: Although morphologic, radiographic, and manometric features of achalasia have been well defined, it has not been established by careful retrospective analysis whether achalasia is a progressive disorder resulting in complete decompensation. STUDY DESIGN: To verify the hypothesis that achalasia is a progressive disease, we retrospectively investigated manometric, radiographic, and symptomatic data in patients with achalasia. Sixty-three patients (36 women and 27 men) with a median age of 44 years (range 11 to 79 years) were evaluated. The duration of symptoms ranged from 1 to 442 months, with a median of 48 months. Patients were divided into four groups according to the duration of symptoms: 36 patients with less than 5 years, 11 with 5 to 10 years, 9 with 10 to 15 years, and 7 with 15 years or more. RESULTS: Contraction pressures of the esophageal body decreased significantly at every level when the duration of symptoms increased (p < 0.04). The percentage of simultaneous waves in the esophageal body rose as the duration of symptoms increased. All waves were synchronous in every patient who had had symptoms for more than 15 years. The maximal width of the esophageal body measured on esophagram became greater with an increase in the duration of symptoms, but this measurement did not reach statistical significance (p = 0.063). The tortuosity of the esophagus, measured by the maximal angle of the esophageal axis, was significantly greater in patients with a longer duration of symptoms (p < 0.02). The type of symptoms was not associated with the duration of symptoms. CONCLUSIONS: Achalasia is a progressive disease, as verified by manometric and radiographic findings. The classification of esophageal motor function expressed by amplitude of contraction pressure and angle of tortuosity is objective and useful. Classification of achalasia by duration of symptoms may be important in treatment selection and effectiveness.  相似文献   
998.
Rett syndrome (RTT) is a neurodevelopmental disorder caused by mutations in the X‐linked gene MECP2. Girls with RTT show dramatic changes in brain function, but relatively few studies have explored the structure of neural circuits. Examining two mouse models of RTT (Mecp2B and Mecp2J), we previously documented changes in brain anatomy. Herein, we use confocal microscopy to study the effects of MeCP2 deficiency on the morphology of dendrites and axons in the fascia dentata (FD), CA1 area of hippocampus, and motor cortex following Lucifer yellow microinjection or carbocyanine dye tracing. At 3 weeks of age, most (33 of 41) morphological parameters were significantly altered in Mecp2B mice; fewer (23 of 39) were abnormal in Mecp2J mice. There were striking changes in the density and size of the dendritic spines and density and orientation of axons. In Mecp2B mice, dendritic spine density was decreased in the FD (~11%), CA1 (14–22%), and motor cortex (~16%). A decreased spine head size (~9%) and an increased spine neck length (~12%) were found in Mecp2B FD. In addition, axons in the motor cortex were disorganized. In Mecp2J mice, spine density was significantly decreased in CA1 (14–26%). In both models, dendritic swelling and elongated spine necks were seen in all areas studied. Marked variation in the type and extent of changes was noted in dendrites of adjacent neurons. Electron microscopy confirmed abnormalities in dendrites and axons and showed abnormal mitochondria. Our findings document widespread abnormalities of dendrites and axons that recapitulate those seen in RTT. J. Comp. Neurol. 514:240–258, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
999.
OBJECTIVE: To estimate the incidence of major and minor congenital malformations among liveborn infants at King Abdulaziz University Hospital, Jeddah, Saudi Arabia. Estimation of risk factors were also evaluated. METHODS: Between March 2004 and May 2005, a total of 5356 babies born at King Abdulaziz University Hospital, were enrolled in this study for malformations. Details of cases were recorded after parents' interviews, clinical, radiological, and laboratory evaluations. RESULTS: One hundred and forty-seven (27.06/1000 livebirth) and 13 (2.39/1000 birth) stillbirth had congenital anomalies. In all livebirth, incidences of major anomalies were 93.9% and minor were 6.1%. Mothers of 95.9% with congenital malformation were healthy, 3.4% were diabetic and 0.7% had cardiac malfomation. In 38.8% of cases parents were consanguineous. Among the liveborn births, the most common system involved was cardiovascular (7.1/1000), followed by musculoskeletal/limb (4.1/1000), external genitalia (2.8/1000), urinary (2.6/1000), multiple chromosomal (2.2/1000), orofacial (1.9/1000), central nervous system (1.9/1000), skin (1.7/1000), multiple single gene (1.3/1000), multiple sequence (0.75/1000), eyes (0.56/1000), unclassified (0.19/1000), musculoskeletal/abdominal (0.19/1000), endocrine (0.19/1000). CONCLUSION: High incidence of major malformation in Jeddah. Importance of Genetic Counseling is revealed in our study since more than three quarters of mothers were under 36 years, and may well plan future pregnancies.  相似文献   
1000.
Objective The objective of this study was to determine the relationship between systemic vascular resistance (SVR), finger & ear photoplethysmographic measurements in 14 adult patients undergoing coronary artery bypass grafting (CABG). Methods Patients were monitored with photoplethysmographs of the finger and ear and continuous cardiac output (QT) via thermodilution catheter. The relationship between SVR, finger plethysmographic amplitude, width and ear plethysmographic amplitude, width was assessed with linear regression. Results The finger plethysmographic amplitude had a low correlation r value = −0.15, while finger plethysmographic width had a better correlation r value = 0.56. The correlation between SVR and ear plethysmographic amplitude and width were −0.24 and 0.62 respectively. Using receiver operating characteristic analysis the ear plethysmographic width had both better sensitivity and specificity than the finger plethysmographic width in identifying high and low SVR. Using a multiple regression analysis, SVR was estimated from the pulse oximeter waveforms: SVR calculated = 27.27 + (3978.53 × Ear pulse oximeter width) − (8.91 × Ear pulse oximeter area) + (1986.3 × Finger pulse oximeter width). Bland–Altman analysis was used the bias was 29.8 dynes s cm−5, standard deviation was 587.3, upper and lower limit of agreement were 1204.45, and −1144.8 dynes s cm−5 respectively. Conclusion The data indicate that pulse width of finger and ear plethysmographic tracing are more sensitive to changes in SVR than the other indices. An appreciation of changes in pulse width may provide valuable evidence with respect to changes in peripheral vascular tone. Awad AA, Haddadin AS, Tantawy H, Badr TM, Stout RG, Silverman DG, Shelley KH. The relationship between the photoplethysmographic waveform and systemic vascular resistance.  相似文献   
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