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1.
Fady K. Balaa T. Clark Gamblin Allan Tsung J. Wallis Marsh David A. Geller 《Journal of gastrointestinal surgery》2008,12(2):338-343
Background Application of linear stapling devices for extrahepatic vascular control in liver surgery has been well-established. However,
the technique for use of stapling devices in hepatic parenchymal transection is not well defined.
Purpose To describe the safety and efficacy of our technique for use of vascular stapling devices in hepatic parenchymal transection
during open right hepatic lobectomy is the purpose of this study.
Methodology We reviewed our experience with 101 consecutive open right hepatic lobectomies performed by a single surgeon between January
2003 and July 2006, in which vascular staplers were utilized for the parenchymal transection phase.
Results Of the 101 patients who underwent resection, 53 (52%) were female. The mean age was 58 years. Malignant disease was the indication
for resection in the majority of patients (88%). Of those with cancer, 78% (69 of 89) had metastatic colorectal cancer, 6%
(5 of 89) had metastatic neuroendocrine tumor, 4% (4 of 89) had hepatocellular carcinoma, 4% (4 of 89) had cholangiocarcinoma,
and the remaining 8% were other metastatic cancers. Twelve patients (12%) underwent resection for hepatic adenoma or symptomatic
benign disease (FNH or hemangioma). Forty-eight patients (48%) underwent a major ancillary procedure at the time of hepatic
resection. Thirty-nine patients (39%) had a nonanatomic wedge resection of a left lobe lesion, 27 patients (27%) had one or
more lesions treated with radiofrequency ablation (RFA), and 6 patients (6%) were treated with a synchronous bowel resection.
The median total operative time was 336 min (range 155–620 min). A Pringle maneuver for temporary vascular inflow occlusion
was utilized in all cases, with a median time of 9 min (range 4–17 min). Ten patients (10%) required blood transfusion during
surgery or in the postoperative period. The maximum transfusion was 2 U of packed red blood cells (PRBC) in seven patients
and 1 U of PRBC in three patients. The mean nadir postoperative hematocrit was 28.2. All patients with malignant disease had
tumor-free margins at the completion of the procedure. The average hospital length of stay was 6.0 days. One patient (1%)
developed a clinically significant bile leak requiring a postoperative endoscopic retrograde cholangiography (ERCP). No patient
required reoperation. The 30 and 60-day postoperative survival was 100%.
Conclusion These findings indicate that application of vascular stapling devices for parenchymal transection in major hepatic resection
is a safe technique, with low transfusion requirements and minimal postoperative bile leak. The technique allows for rapid
transection of the entire right hepatic lobe in under 10 min. Short video clips of the technique will be demonstrated.
Presented at the 2007 American Hepato–Pancreato–Biliary Association, Las Vegas, Nevada, April 19–22, 2007 (oral presentation/video
presentation). 相似文献
2.
3.
Werner E Bischoff Brian K Tucker Michelle L Wallis Beth A Reboussin Michael A Pfaller Frederick G Hayden Robert J Sherertz 《Infection control and hospital epidemiology》2007,28(10):1148-1154
OBJECTIVE: Transmission of Staphylococcus aureus via air may play an important role in healthcare settings. This study investigates the impact of barrier precautions on the spread of airborne S. aureus by volunteers with experimentally induced rhinovirus infection (ie, the common cold). DESIGN: Prospective nonrandomized study. SETTING: Wake Forest University School of Medicine (Winston-Salem, NC).Participants. A convenience sample of 10 individuals with nasal S. aureus carriage selected from 593 students screened for carriage. INTERVENTION: Airborne S. aureus dispersal was studied in the 10 participants under the following clothing conditions: street clothes, surgical scrubs, surgical scrubs and a gown, and the latter plus a face mask. After a 4-day baseline period, volunteers were exposed to a rhinovirus, and their clinical course was followed for 12 days. Daily swabs of nasal specimens, pharynx specimens, and skin specimens were obtained for quantitative culture, and cold symptoms were documented. Data were analyzed by random-effects negative binomial models. RESULTS: All participants developed a common cold. Incidence rate ratios (IRRs) indicated that, compared with airborne levels of S. aureus during sessions in which street clothes were worn, airborne levels decreased by 75% when surgical scrubs were worn (P<.001), by 80% when scrubs and a surgical gown were worn (P<.001), and by 82% when scrubs, a gown, and a face mask were worn (P<.001). The addition of a mask to the surgical scrubs and gown did not reduce the airborne dispersal significantly (IRR, 0.92; P>.05). Male volunteers shed twice as much S. aureus as females (incidence rate ratio, 2.04; P=.013). The cold did not alter the efficacy of the barrier precautions. CONCLUSIONS: Scrubs reduced the spread of airborne S. aureus, independent of the presence of a rhinovirus-induced cold. Airborne dispersal of S. aureus during sessions in which participants wore surgical scrubs was not significantly different from that during sessions in which gowns and gowns plus masks were also worn. 相似文献
4.
Macrophages, mycobacteria and HIV: the role of cytokines in determining mycobacterial virulence and regulating viral replication. 总被引:3,自引:0,他引:3
The marriage of two scourges, one old (mycobacterial disease) and one new (HIV), has presented an enormous challenge to the medical and public health communities, and has stirred renewed interest in mechanisms for immune control of mycobacterial infection. Virulence of both M. avium and M. tuberculosis appears to be inversely related to the capacity of the microorganisms to induce production of protective cytokines in infected hosts. TNF alpha and IFN gamma are central to this process, and mycobacterial polysaccharides may be their main determinant. Despite these similarities, M. tuberculosis and M. avium cause illnesses at the polar extremes of HIV disease. Tuberculosis, occurring early in the course of HIV disease, may promote HIV replication in otherwise latently infected cells via induction of cytokines. As such, the potential exists for accelerated progression to AIDS due to the mutual synergy of these pathogens. 相似文献
5.
6.
Jerold W. Wallis 《European journal of nuclear medicine and molecular imaging》1995,22(6):543-547
Clinical cardiac imaging is hindered by noise due to limited activity and imaging time. Use of 90° dual-detector systems with 90° gantry rotation may provide the best sensitivity/resolution for cardiac imaging, but this option is not readily available to those using a triple-detector system with detectors at 120° intervals. This study utilizes a cardiac/chest phantom to compare several triple-detector orbits, with assessment of sensitivity and resolution. A 180° rotation with reconstruction of two of the three heads was evaluated, resulting in overlapping 180° orbits; use of a starting angle of 165° for the first head placed the overlapping portion of the orbits over the LAO myocardial region, where camera-cardiac distance is most favorable. Use of this overlapping orbit yielded resolution equivalent to a conventional (single-head) 180° rotation. Sensitivity was 87%–90% of that of a 90° dual-detector system, and 16%–20% better than the common practice of using a 120° orbit with reconstruction of 1 /12 heads to achieve 180° of data. Use of 360° acquisition with reconstruction of all three heads provided the greatest sensitivity, though at the expense of some loss in image quality. Thus, for those centers performing cardiac imaging using a triple-detector system, use of overlapping 180° orbits is the preferred acquisition choice. 相似文献
7.
Daniel R. Einstein Blazej Neradilak Nayak Pollisar Kevin R. Minard Chris Wallis Michelle Fanucchi James P. Carson Andrew P. Kuprat Senthil Kabilan Richard E. Jacob Richard A. Corley 《Anatomical record (Hoboken, N.J. : 2007)》2008,291(12):1628-1648
We present the results of an automated analysis of the morphometry of the pulmonary airway trees of the Sprague–Dawley rat. Our work is motivated by a need to inform lower‐dimensional mathematical models to prescribe realistic boundary conditions for multiscale hybrid models of rat lung mechanics. Silicone casts were made from three age‐matched, male Sprague–Dawley rats, immersed in a gel containing a contrast agent and subsequently imaged with magnetic resonance (MR). From a segmentation of this data, we extracted a connected graph, representing the airway centerline. Segment statistics (lengths and diameters) were derived from this graph. To validate this MR imaging/digital analysis method, airway segment measurements were compared with nearly 1,000 measurements collected by hand using an optical microscope from one of the rat lung casts. To evaluate the reproducibility of the MR imaging/digital analysis method, two lung casts were each imaged three times with randomized orientations in the MR bore. Diameters and lengths of randomly selected airways were compared among each of the repeated imaging datasets to estimate the variability. Finally, we analyzed the morphometry of the airway tree by assembling individual airway segments into structures that span multiple generations, which we call branches. We show that branches not segments are the fundamental repeating unit in the rat lung and develop simple mathematical relationships describing these structures for the entire lung. Our analysis shows that airway diameters and lengths have both a deterministic and stochastic character. Anat Rec, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
8.
Michael A Tangrea Rodrigo F Chuaqui John W Gillespie Mamoun Ahram Gallya Gannot Benjamin S Wallis Carolyn J M Best W Marston Linehan Lance A Liotta Thomas J Pohida Robert F Bonner Michael R Emmert-Buck 《Diagnostic molecular pathology》2004,13(4):207-212
Tissue microdissection is an important method for the study of disease states. However, it is difficult to perform high-throughput molecular analysis with current techniques. We describe here a prototype version of a novel technique (expression microdissection) that allows for the procurement of desired cells via molecular targeting. Expression microdissection (xMD) offers significant advantages over available methods, including an increase in dissection speed of several orders of magnitude. xMD may become a valuable tool for investigators studying cancer or other disease states in patient specimens and animal models. 相似文献
9.
The neuroendocrine stress hormone norepinephrine augments Escherichia coli O157:H7-induced enteritis and adherence in a bovine ligated ileal loop model of infection 下载免费PDF全文
Vlisidou I Lyte M van Diemen PM Hawes P Monaghan P Wallis TS Stevens MP 《Infection and immunity》2004,72(9):5446-5451
The role of the neuroendocrine environment in the pathogenesis of enteric bacterial infections is increasingly being recognized. Here we report that norepinephrine augments Escherichia coli O157:H7-induced intestinal inflammatory and secretory responses as well as bacterial adherence to intestinal mucosa in a bovine ligated ileal loop model of infection. Norepinephrine modulation of enteritis and adherence was dependent on the ability of E. coli O157:H7 to form attaching and effacing lesions. 相似文献
10.
The morphology of immune reactions in normal, thymectomized and reconstituted mice: I. The response to sheep erythrocytes 总被引:16,自引:0,他引:16 下载免费PDF全文
A. J. S. Davies R. L. Carter Elizabeth Leuchars Valerie Wallis P. C. Koller 《Immunology》1969,16(1):57-69
The response to sheep red blood cells has been studied in the lymph nodes draining their site of injection in normal mice, and in thymectomized, irradiated, bone-marrow injected mice with and without a reconstituting thymus graft. By using a chromosome marker to differentiate between cells derived from the bone-marrow and thymus graft it has proved possible to show that the immune response should be thought of in terms of at least two cell populations. Cells of thymic origin are stimulated to mitotic activity in the interfollicular cortex, and their activity precedes both antibody production and morphological signs of activity in the follicular regions. Mitotic divisions of cells of bone-marrow origin reached a peak a day later than did the thymic cells and their activity was sustained. Follicular enlargement and germinal centre production were coincident in time both with antibody production and bone-marrow cell mitotic activity. Lymph nodes of animals lacking a thymic influence showed only minor changes after antigenic stimulation and these were restricted to the follicular regions. There appeared to be only a small quantitative difference between the responses of normal and of reconstituted animals. 相似文献