Pulmonary vein dissection during mapping of atrial fibrillation.
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Publications and source records attributed to C C Wu.
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OBJECTIVE: The purpose of this study was to evaluate the feasibility of the use of deoxyribonucleic acid microsatellite alterations in cervical epithelia in the prediction of high-grade dysplasia and to compare it with a strategy based on human papillomavirus testing. STUDY DESIGN: Our prospective study subjects were from a cohort of 498 women with minimally abnormal Papanicolaou test results including atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesion who had documented repeated Papanicolaou and human papillomavirus tests. Of these, 52 eligible patients having conizations or hysterectomies as their histologic outcomes were subjected to tests of loss of heterozygosity on a panel of 5 microsatellites (D3S1110, THRB, D3S1228, D6S291, D3S1289) within the deoxyribonucleic acid of exfoliated cervical epithelia. These genetic alterations were analyzed through fluorescence polymerase chain reaction by comparison of allele ratios of exfoliated cells with those of normal control tissue. Predictive values for high-grade cervical dysplasia and cancer between this deoxyribonucleic acid marker and human papillomavirus status were compared. RESULTS: With the use of loss of heterozygosity in at least one locus for predicting high-grade cervical neoplastic lesion, the sensitivity, specificity, positive predictive value, and negative predictive value were 96.7%, 59.1%, 76.3%, and 92.9%, which were superior to those of the human papillomavirus test (80%, 59.1%, 72.7%, and 92.9%). As a triage for atypical squamous cells of undetermined significance, its sensitivity and negative predictive value were up to 100%. CONCLUSION: The promising results on determining microsatellite alteration in dysplastic lesions might imply that it is possible to detect the earliest changes by potential molecular markers with exfoliated cervical epithelial cells.
The objective of the present study was to elucidate the kinetics of humoral and cellular immune responses of turkey poults infected with turkey coronavirus (TCV). Turkey poults were orally inoculated with TCV at 10 d of age, and the immune responses were analyzed at 1, 3, 7, 14, 21, 28, 42, and 63 d postinfection (PI) in three different experiments. Total Ig to TCV was initially detected at 7 and 14 d PI in Experiments 1 and 3. In addition, Ig gradually increased from 7 to 21 d PI and remained at 80 immunofluroescent antibody assay (IFA) titers or more thereafter. Lymphocyte proliferation responses of spleen cells to concanavalin A were higher in TCV-infected turkeys than in noninfected control turkeys with significant differences (P < 0.05) being noted at 14 and 63 d PI in Experiment 2 and at 3 and 28 d PI in Experiment 3. Strong IFA staining response to TCV antigen was observed in intestines of turkeys at 1, 3, and 7 d PI, and the response declined from 14 to 28 d PI in Experiment 3. In Experiment 3, the IgG isotype antibody response to TCV was markedly increased after 21 d PI and remained high until 63 d PI. The IgM isotype antibody response to TCV was 1.40 and 0.91 at 7 and 14 d PI, respectively. The IgA isotype antibody response to TCV was very low as detected at 7 (0.13), 14 (0.20), and 21 (0.17) d PI. Turkeys infected with TCV had significantly higher (P < 0.05) antibody response to sheep erythrocytes than noninfected controls at 7 d PI. Virus-specific lymphocyte proliferation response of spleen cells was significantly stimulated (P < 0.05) at 63 d PI in Experiment 3. The proportion of the CD4+ subpopulation of T lymphocytes was significantly increased (P < 0.05) at 1, 7, and 21 d PI in Experiment 3. The results indicate that humoral and cellular immunities to TCV are elicited in turkeys following infection with TCV.
We conducted an experiment with broilers to determine if prior exposure to Staphylococcus aureus would facilitate the systemic infiltration of this pathogen following intradermal footpad challenge with live S. aureus. Litter-raised broilers were sensitized at 3 and 4 wk of age with s.c. injections in the neck with heat-killed S. aureus diluted in polyethylene glycol (PEG). Equal numbers of control birds were injected at the same times with PEG. At 7 wk of age, chicks previously sensitized to killed S. aureus or injected with PEG were injected intradermally in the right footpad with PBS or live S. aureus. The left footpads of all birds were injected with PBS. The difference in thickness between the right and left footpads was determined at 0, 24, and 48 h postchallenge. Blood, liver, spleen, lung, and synovial fluid were collected six times between 1 and 48 h postchallenge to determine the recovery of S. aureus. Sensitized and non-sensitized birds showed footpad swelling following challenge with live S. aureus in the right footpad (P < 0.001). Injection of PBS did not induce footpad swelling. Birds injected in the footpads with live S. aureus as compared to PBS had significantly higher isolation rates of S. aureus in the spleen, liver, and blood; however, recovery of S. aureus from S. aureus-sensitized and PEG-injected birds was not significantly different. Time postchallenge (1, 3, 7, 11, 24, and 48 h) had no significant effect on the recovery of S. aureus. It was concluded that the intradermal challenge of the footpad with S. aureus resulted in systemic infiltration of S. aureus into the spleen, liver, and blood. Prior exposures to killed S. aureus as compared to PEG controls did not affect the systemic distribution of S.
OBJECTIVES: To examine the role of endogenous nitric oxide (NO) in the pathogenesis of hypertension and insulin resistance in chronic hyperinsulinemic rats. METHODS: Sustained hyperinsulinemia was achieved by insulin infusion (21.5 pmol/kg per min) via subcutaneous osmotic minipump for 6 weeks. NO synthase inhibitor, Nomega-nitro-L-arginine methyl ester (L-NAME, 5 mg/kg per day) was given orally after 4 weeks of vehicle or insulin infusion. The systolic blood pressure (SBP) was measured under conscious state by an electrosphygmomanometer before and after drug treatments. RESULTS: Insulin infusion alone significantly increased SBP from 134 +/- 3 to 156 +/- 2 mmHg by week 4 and further to 158 +/- 3 mmHg by week 6 of insulin infusion. The insulin-infused rats had markedly decreased insulin sensitivity, as reflected by an elevated steady-state plasma glucose level estimated by the insulin suppression test. There were no significant differences in plasma glucose and triglyceride levels between rats with and without insulin infusion. When hypertension had been established in rats receiving insulin infusion for 4 weeks, superimposed L-NAME on insulin infusion for additional 2 weeks further increased SBP by 18 +/- 2 mmHg (from 157 +/- 2 to 175 +/- 2 mmHg). Plasma levels of NO metabolites (NOx) significantly decreased from 13.7 +/- 1.1 micromol/l during the control period to 6.1 +/- 0.6 micromol/l after 4 weeks of insulin infusion and further reduced to 4.1 +/- 0.5 micromol/l after combined infusion of L-NAME and insulin. L-NAME treatment alone for 2 weeks in control rats significantly increased SBP by 33 +/- 2 mmHg (from 133 +/- 2 to 166 +/- 2 mmHg) and plasma insulin levels, as a consequence of insulin resistance. Despite marked increases in blood pressure due to infusion of insulin alone or in combination with L-NAME, the sodium balance, urinary sodium and water excretions, water intake and body weight gain of insulin/L-NAME-treated rats were not significantly different from rats without insulin infusion. CONCLUSIONS: Sustained hyperinsulinemia causes partial impairment of NO production that may contribute to the development of insulin resistance and hypertension. Additional inhibition of NO synthesis by L-NAME accentuates the blood pressure elevation and insulin resistance in hyperinsulinemic rats. Furthermore, a rightward shift of the renal arterial pressure-natriuretic function relationship occurred in this hypertensive model.
BACKGROUND: Femoral shaft aseptic nonunions associated with plating failure resulting from screw breakage are rare, and the treatment is complex and yet to be defined. The aim of this prospective study was to develop a better technique for the treatment of this complication. METHODS: Eight consecutive adult patients who sustained femoral shaft aseptic nonunions associated with plating failure resulting from screw breakage were treated. The procedure involved skeletal traction in the femoral condyle, removal of the broken screws after making a bony window in the lateral cortex, with or without lengthening the femur, stabilization with a static locked nail, and finally, corticocancellous bone grafting. Postoperatively, ambulation with protected weight bearing was encouraged as early as possible. RESULTS: All eight patients were followed up for at least 1 year (range, 1.1-4.7 years), and seven nonunions healed. The median union period was 4 months (range, 3-6 months). One patient had a persistent nonunion, and the locked nail broke at 6 months. The nonunion healed 4 months after closed revision with a new locked nail. CONCLUSION: The described technique has both theoretical and clinical merits. All abnormalities can be corrected concomitantly. The success rate is high and the complication rate is low. Whenever possible, therefore, it may be used to treat all indicated cases of nonunion.
SUMMARY: The benefits of laparoscopic appendectomy appear to be controversial. Since 1994, several abdominal procedures have been completed by using the needlescopic technique, but there appear to be no prospective studies to demonstrate the perceived benefits of needlescopic appendectomy. The authors compared open, laparoscopic, and needlescopic appendectomy in a randomized fashion with regard to duration of surgery, length of hospitalization, analgesic dosage, and surgery-associated complications. From March to July 1998, 75 patients admitted at the emergency station of the authors' hospital with a final diagnosis of acute appendicitis without tumor formation were randomized to receive one of the three treatment categories: open (OA), laparoscopic (LA), and needlescopic (nLA) appendectomy. Laparoscopic and needlescopic appendectomy were performed by using a three-port technique, although the size of the trocar used varied. There were 26 patients in the OA group, 23 in the LA group, and 26 in the nLA group. The mean operation durations for the OA, LA, and nLA groups were 55.4 +/- 28.0 minutes, 69.1 +/- 48.8 minutes, and 62.3 +/- 26.3 minutes, respectively, and these were not significantly different from one another. The mean number of the analgesic doses (Pethidine 1 mg/kg) required was 1.3 +/- 1.2 mg/kg, 0.5 +/- 0.8 mg/kg, and 0.2 +/- 0.6 mg/kg, respectively. Significant differences were noted when comparing the OA with the LA or nLA groups (OA vs. LA, P = 0.02; OA vs. nLA, P = 0.0002; LA vs. nLA, P = 0.06). The mean oral intake durations were 32.2 +/- 16.9 hours, 21.0 +/- 14.6 hours, and 20.8 +/- 16.4 hours, respectively, after surgery for the OA, LA, and nLA groups, and the between-group differences were statistically significant for the OA versus LA group ( P = 0.004) and for the OA versus nLA group ( P = 0.003). The mean durations of hospitalization for the OA, LA, and nLA groups were 3.6 +/-1.8 days, 2.8 +/- 1.4 days, and 2.4 +/- 0.9 days, and difference was detected between the OA and the nLA groups ( P = 0.02). The OA group rendered a greater wound-complication rate and ileus than did the other two groups, but the differences were not detected between the three categories ( P = 0.065, 0.6935). The result of the current study confirmed that the nLA procedure is a feasible and safe one. The nLA procedure provided substantial advantages over the OA procedure in the contexts of diminished postoperative pain and shorter hospital stay without significant increases in postoperative complication rate or surgical time.
Attachment of Mycobacterium avium subsp. paratuberculosis to host tissue and penetration of mucosal surfaces are pivotal events in the pathogenesis of Johne's disease. Fibronectin (FN) binding is required for attachment and internalization of several mycobacteria by epithelial cells in vitro. The objective of this study was to further characterize the FN binding activity of M. avium subsp. paratuberculosis. Although the bacteria bound FN poorly at pH above 7, brief acid pretreatment greatly enhanced FN binding within the pH range (3 to 10) studied. A 4.6-kbp fragment from an M. avium subsp. paratuberculosis genomic library was found to contain a 1,107-bp open reading frame that shows very high nucleotide sequence identity with that of the FN attachment protein (FAP) gene of M. avium subsp. avium. Pretreatment of FN with an FN-binding peptide from M. avium subsp. avium FAP abolished FN binding, indicating that M. avium subsp. paratuberculosis binds FN in a FAP-dependent manner. Pretreatment of M. avium subsp. paratuberculosis with anti-FAP immunoglobulin G did not abrogate FN binding; blocking occurred only when anti-FAP was added together with FN. FAP was detected by immunofluorescence only in lipid-extracted M. avium subsp. paratuberculosis. Western blotting and immunoelectron microscopy revealed that FAP is located near the interior of the cell envelope of M. avium subsp. paratuberculosis. The results indicate that a FAP homologue mediates the attachment of FN to M. avium subsp. paratuberculosis. Further, given the subcellular location of FAP, it is considered that this protein operates at the terminus of a coordinated FN binding system in the cell envelope of M. avium subsp. paratuberculosis.
Quality control (QC) standards for the in vitro antimicrobial susceptibility testing of two fastidious veterinary pathogens, Actinobacillus pleuropneumoniae and Haemophilus somnus, were developed in a multilaboratory study according to procedures established by the National Committee for Clinical Laboratory Standards for broth microdilution and disk diffusion testing. The medium recommended for the broth microdilution testing is cation-adjusted Mueller-Hinton broth supplemented with 2% lysed horse blood, 2% yeast extract, and 2% supplement C. This medium has been designated veterinary fastidious medium. The medium recommended for the disk diffusion testing is chocolate Mueller-Hinton agar. The recommended QC organisms are A. pleuropneumoniae ATCC 27090 and H. somnus ATCC 700025. The QC MICs of ceftiofur, enrofloxacin, florfenicol, gentamicin, penicillin, tetracycline, tilmicosin, and trimethoprim-sulfamethoxazole were determined for each isolate, as were the zone size ranges. Of the results from the participating laboratories, 94.0% of the zone diameter results and 97.0% of the MIC results fell within the suggested QC ranges for all compounds. These QC guidelines should allow greater accuracy in interpreting results when testing these antimicrobial agents against fastidious pathogens.
AIMS: To evaluate the therapeutic effects of excimer laser phototherapeutic keratectomy (PTK) combined with therapeutic contact lens for painful recurrent corneal erosions (RCE) secondary to bullous keratopathy (BK) not suitable for penetrating keratoplasty. METHODS: Excimer laser PTK was performed prospectively in eight eyes with painful RCE due to BK visually expecting no benefit from penetrating keratoplasty. After mechanical removal of the epithelium, the corneas were ablated with 50 pulses in the central 6.5 mm zone (ablation rate 0.25 microm per pulse) and another 200 pulses for polishing the periphery. After PTK, therapeutic contact lenses were applied for 3 months. The mean follow up period after PTK was 10.9 months (ranging from 6 to 15 months). RESULTS: All patients experienced relief of their pain symptoms after the epithelium healed. Only one patient complained of occasional stinging pain with intermittent recurrence of small bullae. He refused a second treatment because the pain was much less than that before the surgery and quite tolerable. No infection or other complications were noted. CONCLUSION: PTK with deeper ablation and adjunctive therapeutic contact lens is an easy to perform and effective treatment with less recurrence rate for patients with BK and poor visual potential.
We propose a novel image-recovery method using the covariance matrix of the red-green-blue (R-G-B) color histogram and tensor theories. The image-recovery method is called the color histogram normalization algorithm. It is known that the color histograms of an image taken under varied illuminations are related by a general affine transformation of the R-G-B coordinates when the illumination is changed. We propose a simplified affine model for application with illumination variation. This simplified affine model considers the effects of only three basic forms of distortion: translation, scaling, and rotation. According to this principle, we can estimate the affine transformation matrix necessary to recover images whose color distributions are varied as a result of illumination changes. We compare the normalized color histogram of the standard image with that of the tested image. By performing some operations of simple linear algebra, we can estimate the matrix of the affine transformation between two images under different illuminations. To demonstrate the performance of the proposed algorithm, we divide the experiments into two parts: computer-simulated images and real images corresponding to illumination changes. Simulation results show that the proposed algorithm is effective for both types of images. We also explain the noise-sensitive skew-rotation estimation that exists in the general affine model and demonstrate that the proposed simplified affine model without the use of skew rotation is better than the general affine model for such applications.
The CTLA4 (cytotoxic T lymphocyte associated antigen-4) gene encodes the T cell receptor involved in the control of T cell proliferation and mediates T cell apoptosis. C-T polymorphism is present at position -318 from the ATG start codon in the promoter region of the gene. We report a study on the polymorphism in 347 unrelated children with type 1 diabetes mellitus (DM) (age at diagnosis 7.2+/-3.8 years) and their 260 healthy siblings as controls. Genotype C/C conferred a risk of type 1 DM (RR = 2.02, 95% CI 1.32-3.10, pc = 0.0033). The gene frequency of the C allele was higher in patients (RR = 1.91, 95% CI 1.28-2.84, pc = 0.0026). The gene frequency and phenotype frequency of the T allele were negatively associated with type 1 DM (RR = 0.52, 95% CI 0.35-0.78, pc = 0.0026 and RR = 0.49, 95% CI 0.32-0.76, pc = 0.0022, respectively). The frequency of genotype C/T was lower in patients (RR = 0.50, 95% CI 0.32-0.78, pc = 0.0051). This study demonstrates that nucleotide -318 C-T polymorphism of the CTLA4 gene is associated with type 1 DM. The promoter allele -318 C confers a risk of type 1 DM but allele -318 T confers protection against this disease.
A prospective study was conducted to develop a better technique for ankle fusion. Eleven consecutive patients were treated using the tension-band technique for ankle fusion and underwent follow-up for a minimum of 2 years (range: 2-5 years). All 11 patients achieved solid fusion for a fusion rate of 100%. Average time to fusion was 3 months (range: 2-6 months). The indication for ankle fusion was intractable aching pain that could not be controlled by conservative methods. Two of 11 patients underwent surgery due to infected arthritis. After ankle fusion, there was no recurrence of infection during a 3-year follow-up period. The technique included osteotomy of the bimalleoli from the inside out, removal of articular cartilage and preserving wedge space for cancellous bone grafting, with or without staple stabilization, and external immobilization supplementation. The functional outcome in all 11 patients improved from unsatisfactory preoperatively to satisfactory at latest follow-up (P<.001). No significant complications were noted. This simple technique proved excellent for ankle fusion with a satisfactory outcome and is recommended for treating severe ankle arthropathies.
Vertical banded gastroplasty (VBG) is an effective treatment for morbid obesity. Recent advancement in laparoscopic surgery has made laparoscopic VBG possible. The authors compared retrospectively the outcomes of laparoscopic VBG versus open VBG in patients with morbid obesity. From June 1998 to April 1999, 100 patients (18 men, 82 women; average age, 32.6 years) underwent laparoscopic VBG, and 40 patients (7 men, 33 women; average age, 28.8 years) underwent conventional open VBG. The two groups were similar regarding sex, age, and body mass index distribution. Mean surgical time, blood loss estimate, duration of postoperative recovery, analgesic usage, complications, and weight reduction were compared among the two groups. Laparoscopic VBG was successful in 99 (99%) of the 100 patients. Mean surgical time was longer in duration for the laparoscopic VBG group than it was for the open VBG group (173 vs. 101 minutes, P < 0.01). The laparoscopic VBG group had earlier flatus passage (1.9 vs. 2.6 days; P < 0.01), less usage of analgesics (meperidine 50 mg/unit; 0.9 vs. 2.3 units; P < 0.01), and a shorter postoperative hospital stay (3.7 vs. 6.0 days; P < 0.01). Estimated blood loss, surgical complication rate, and weight reduction were similar among the two groups. Although laparoscopic VBG required a longer surgical time and was technically more demanding, it resulted in shorter recovery time, less analgesic use, and less severe physical discomfort. The authors' findings show that the two methods were approached safely equally.
BACKGROUND AND PURPOSE: Ischemic patterns in patients with syndrome X are thought to differ from those in patients with myocardial bridge, because the mechanisms of coronary flow reduction in these two diseases are different. The aim of this study was to compare the ischemic patterns in patients with syndrome X and those with myocardial bridge through the use of dobutamine stress echocardiography (DSE) and stress thallium-201 single-photon emission computed tomography (SPECT). METHODS: Twenty-six patients with typical angina and stress-induced ST-segment depression were enrolled. All patients underwent coronary angiography, DSE, and stress thallium-201 SPECT within 7 days after enrollment. RESULTS: Of the 26 patients enrolled, 10 had myocardial bridge of the left anterior descending artery and 16 had syndrome X. Among patients with myocardial bridge, myocardial dyssynergy was found by DSE in five patients and reversible or fixed thallium-201 perfusion defects were found in four. Seven patients with myocardial bridge had reverse redistribution patterns on thallium-201 scintigraphy. In the 16 patients with syndrome X, myocardial dyssynergy was found by DSE in only one patient (p = 0.018 vs myocardial bridge group) and reversible or fixed thallium-201 perfusion defects were found in nine (p > 0.05 vs myocardial bridge group). Four patients with syndrome X had reverse redistribution patterns on thallium-201 scintigraphy. The resting left ventricular end-diastolic pressure was higher in patients with myocardial bridge than in those with syndrome X (17 +/- 4 vs 12 +/- 5 mm Hg, p = 0.02). CONCLUSIONS: The most common ischemic patterns in patients with syndrome X were chest pain and stress-induced ST-segment depression, followed by myocardial perfusion defects. Dobutamine-induced dyssynergy was rare. Left ventricular end-diastolic pressure elevation and dobutamine-induced wall motion abnormalities were more common in patients with myocardial bridge than in those with syndrome X.
Antibodies to infectious bronchitis virus (IBV) cross-react with turkey coronavirus (TCV) in immunofluorescence assay (IFA) indicating that IBV and TCV may share an amino acid sequence similarity. To determine its extent, the gene encoding the nucleocapsid (N) protein of TCV was amplified by reverse transcription-PCR (RT-PCR) from RNA purified from intestines of embryos of turkeys infected with various TCV isolates and from allantoic fluid of chicken embryos infected with IBV M41 strain, the obtained N genes were cloned, sequenced and compared with known sequences of N genes of five IBV strains. The primers for amplification were designed from the genome of IBV PCR products were obtained only from two of eight TCV isolates tested. It was found that the two TCV isolates were identical with five IBV strains by 90.1-94.1% at the N gene level. It was also observed that the N gene of eight TCV isolates originating from various regions of the USA could not be amplified by the primers designed from the N gene of bovine coronavirus (BCV).
BACKGROUND: The EEG-Bispectral Index (BIS) is a processed EEG information that has been validated as a means to measure the hypnotic effect of anesthetic drugs. In this study we evaluated the BIS changes in induction of anesthesia with ketamine in comparison with that of thiamylal. METHODS: Forty ASA class I and II adult female patients undergoing elective gynecologic surgeries were enrolled into this randomized, prospective study. No premedication was given to the patient. In each patient EEG was recorded continuously from the frontal electrodes using Aspect A-1050 monitor after his arrival at the operating room. Blood pressure and heart rate were also recorded throughout the surgery. After steady baseline recordings of all necessary parameters having been accomplished Group K patients (n = 20) were given an induction dose of ketamine 1.5 mg/kg i.v., whereas Group T patients (n = 20) received thiamylal 5 mg/kg i.v. When loss of consciousness was ascertained, intubation was performed after administration of succinylcholine 1 mg/kg i.v. and anesthesia was maintained with isoflurane-nitrous oxide-oxygen. Demographics, BIS values, HR, BP were analyzed and compared. RESULTS: The demographics were comparable between the two groups. Both groups showed a mean value of BIS of 96 with comparable BP and HR before induction. After study drug the post-induction BIS for ketamine was 94 as against 51 for thiamylal (P < 0.05), 91 against 43 post-succinylcholine (P < 0.05), 92 against 53 post-intubation (P < 0.05) and 45 against 37 five min after isoflurane. BIS remained below 60 throughout the entire course of anesthesia and returned to above 95 on emergence in both groups. None of the patients reported awareness, recall, delirium or hallucination during anesthesia. CONCLUSIONS: Ketamine-induced dissociative anesthesia produces persistently elevated BIS index which is different from thiamylal and those reported with other conventional anesthetic agents. The established range of BIS index appears not to be applicable in patients under ketamine anesthesia. Monitoring the depth of ketamine anesthesia remains to be a challenging problem.