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51.
We report a case of disseminated meningospondylodiscitis in an elderly diabetic patient caused by Fusarium oxysporum. As the clinical presentation was nonspecific, the diagnosis of the condition could only be arrived at after laboratory and imaging studies. The diagnosis of the condition requires a high index of suspicion. Patient underwent thorough surgical debridement along with a short course of variconazole and remained asymptomatic after 36 months of diagnosis. Fusarium is a large genus of filamentous fungi widely distributed in soil and in association with plants. It is known to cause local infections (nail, cornea) in healthy humans and disseminated infection only in the immunocompromised.  相似文献   
52.
OBJECTIVES: This study compared the accuracy of three radiographic imaging modalities for the detection of artificially induced radicular fractures on maxillary anterior teeth. METHODS: Fractures were induced in 28 of 54 maxillary incisors in 15 cadaver specimens using a distally directed force. Radiographs evaluated included conventional two-dimensional direct digital radiographs (DDI), unprocessed Tuned Aperture Computed Tomography (TACT-U) and iteratively restored TACT (TACT-IR). Eight observers recorded their findings using a five-point confidence-rating scale. Receiver Operating Characteristic (ROC) analyses were done, followed by ANOVA to test for significant effects of observers, imaging modality and fracture location. Post hoc tests were carried out in instances where ANOVA indicated significance. RESULTS: The areas under the ROC-curves (A(z)) were, respectively: DDI: 0.53; TACT-U: 0.83 and TACT-IR: 0.97. TACT-IR and TACT-U performed significantly better than DDI (P < 0.001) with TACT-IR providing a higher detection accuracy than TACT-U (P < 0.033). A difference in detection accuracy was also noted based on fracture location (P < 0.001). Tukey's post hoc analyses revealed that fractures extending beyond the middle third of the root were more accurately detected. Inter-observer agreement was 0.68, and intra-examiner agreement, 0.87 (kappa analysis). CONCLUSIONS: TACT performed significantly better than direct digital images in detecting trauma-induced radicular fractures in unrestored, maxillary anterior teeth.  相似文献   
53.
Background:With the emergence of lifestyle diseases in epidemic proportions, obstructive sleep apnea (OSA) is being increasingly recognized in less developed countries as well.Aim:We sought to study the demographic, clinical, and polysomnographic (PSG) predictors of OSA severity in a cohort of South Indian patients.Results:There were 152 (119 males and 33 females) subjects with a mean age of 53.8 years and body mass index (BMI) of 29.31. Mean AHI was 36.2/h (range: 5.1-110) and 66 subjects had severe OSA. Around 12% had the presenting complaint as insomnia, mainly of sleep maintenance. Of the subjects, 35% had witnessed apneas and 67% had excessive daytime sleepiness (EDS); 40% of patients had ≥2 risk factors. PSG parameters showed short sleep onset latency with a high arousal index. Mean apnea duration was 24.92 s. We found that age >55 years, BMI >25 kg/m2, witnessed apneas, EDS, hypertension, dyslipidemia, reduced slow wave sleep duration, mean apnea duration >20 s, and desaturation index >10/h correlated well with OSA severity while the arousal index, sleep latency and efficiency, and exposure to smoking and alcohol showed no association.Conclusions:Older subjects with witnessed apneas are likely to have more severe OSA. Even though overall sleep architecture was similar between the groups, severe OSA had shorter slow wave sleep, longer apneas, and higher nocturnal hypoxemia.  相似文献   
54.
INTRODUCTION: Surgical morbidity and mortality rates are high in patients with Cushing's syndrome. Nevertheless, simultaneous bilateral laparoscopic adrenalectomy (LA) is feasible in these patients with less morbidity and good long-term results. BACKGROUND AND RESULTS: Consecutive 22 patients who underwent LA for Cushing's syndrome between 2003 and 2010 in our institute were retrospectively studied. Ninteen patients underwent bilateral simultaneous and three underwent unilateral LA. Seven patients had Cushing's syndrome after failed pituitary surgery and five each had ectopic adrenocorticotrophic hormone dependent syndrome and bilateral macronodular hyperplasia respectively. LA was bilaterally done by lateral transabdominal adrenalectomy in 15 patients and retroperitoneal endoscopic adrenalectomy in 4 on the right side. Mean operative time for simultaneous bilateral cases was 199.45±72.43 minutes with mean blood loss of 72.72±48.6 mL. Patients were fit for discharge by the fifth postoperative day from the surgical aspect. Surgical complication rate was 26% that included wound infections in two, port site hernia, pleural effusion, and atelectasis in one each. One patient died of sepsis (5% mortality). Satisfactory metabolic control was achieved in all observable patients in the long term although Addisonian crisis and Nelson syndrome were seen in 26% and 15% respectively. CONCLUSION: LA has all advantages of minimal access surgery in patients with Cushing's syndrome who are immunocompromised and at high risk of delayed wound healing and infections. Magnification decreases the risk of retained adrenal remnants. Despite advances in minimal access surgery, perioperative morbidity continues to be significant for the procedure.  相似文献   
55.
BACKGROUND: The frequency and outcome of hepatitis C virus (HCV) infection in recipients of hearts from HCV-infected donors remains poorly characterized. METHODS: Between 1991 and 1999, 10 anti-HCV-negative patients received hearts from donors who were anti-HCV and HCV RNA-positive. Each recipient was tested for anti-HCV and HCV RNA and serially evaluated for liver dysfunction. Recipient records were reviewed for cumulative steroid boluses in the first posttransplant year and other components of the immune suppression regimen. We analyzed recipient outcome in relation to the virologic status of the donor, including the level of HCV RNA and genotype and the type of antirejection therapy. RESULTS: All 10 recipients became HCV RNA positive. Donor-recipient pairs expressed identical genotypes in each instance. Six of nine evaluable recipients developed biochemical evidence of hepatitis. Recipients with genotype 1 (1a, 1b) accounted for five of the six cases, and all patients with genotype 1 developed hepatitis. Severe liver injury occurred in two patients. Two deaths occurred, both of which were genotype 1 patients who had been given multiple boluses of corticosteroids in the first posttransplant year. No definite relationship between viral load in the donor and recipient outcome was found. CONCLUSION: Transmission of HCV infection from cardiac donors who are viremic at the time of organ donation occurs with high frequency and can cause severe hepatitis. Hearts from infected patients should probably be restricted to those recipients who already have evidence for hepatitis C or are in need of emergent transplantation.  相似文献   
56.
Nair KK  Zisman LS  Lader E  Dimova A  Canver CC 《The Annals of thoracic surgery》2003,75(1):282-4; discussion 284-5
Anomalous origin of the left coronary artery from the pulmonary artery is a congenital coronary artery malformation most commonly present in infancy. A variety of surgical procedures have been described to achieve physiological correction of the coronary flow abnormalities. These techniques are effective as long as there is potential for myocardial recovery. However the sequelae of chronic myocardial ischemia that characterize this entity often irreversibly damage the heart and preclude correction and palliation of the native anomaly. In this type of setting, heart transplantation is a realistic option. Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) occasionally presents in adulthood. Anatomic repair with a two coronary artery system may not be optimal in patients presenting with ischemic cardiomyopathy. We report an adult patient with platelet factor 4 (PF4) antibodies who underwent orthotopic heart transplantation (OHT) for ALCAPA.  相似文献   
57.
Morphometric assessments, such as muscle density and body fat distribution, have emerged as strong predictors of cardiovascular risk and postoperative morbidity and mortality. To date, no study has examined morphometric mortality risk prediction among kidney transplant (KT) candidates. KT candidates, waitlisted 2008‐2009, were identified (n=96) and followed to the earliest of transplant, death, or administrative end of study. Morphometric measures, including abdominal adipose tissue, paraspinous and psoas muscle composition, and aortic calcification, were measured from CTs. Risk of waitlist mortality was examined using Cox proportional hazard regression. On adjusted analyses, radiologic measures remained independently and significantly associated with lower waitlist mortality; the addition of radiologic measures significantly improved model predictive ability over models containing traditional risk factors alone (net reclassification index: 0.56, 95% CI: 0.31‐0.75). Higher psoas muscle attenuation (indicative of leaner muscle) was associated with decreased risk of death (aHR: 0.93, 95% CI: 0.91‐0.96, P<.001), and for each unit increase in lean paraspinous volume, there was an associated 2% decreased risk for death (aHR: 0.98, 95% CI: 0.96‐0.99, P=.03). Radiologic measures of lean muscle mass, such as psoas muscle attenuation and paraspinous lean volume, may improve waitlist mortality risk prediction and candidate selection.  相似文献   
58.

Aim

Neoadjuvant rectal (NAR) score is an early surrogate for longer-term outcomes in rectal cancer undergoing radiotherapy and resection. In an era of increasing organ preservation, resection specimens are not always available to calculate the NAR score. Post-treatment magnetic resonance imaging (MRI) re-staging of regression is subjective, limiting reproducibility. We explored the potential for a novel MRI-based NAR score (mrNAR) adapted from the NAR formula.

Methods

Locally advanced rectal cancer patients undergoing neoadjuvant therapy (nCRT) and surgery were retrospectively identified between 2008 and 2020 in a single cancer network. mrNAR was calculated by adapting the NAR formula, replacing pathological (p) stages with post-nCRT MR stages (ymr). Cox regression assessed relationships between clinicopathological characteristics, NAR and mrNAR with overall survival (OS) and recurrence-free survival (RFS).

Results

In total, 381 NAR and 177 mrNAR scores were calculated. On univariate analysis NAR related to OS (hazard ratio [HR] 2.05, 95% confidence interval [CI] 1.33–3.14, p = 0.001) and RFS (HR 2.52, 95% CI 1.77–3.59, p = 0.001). NAR 3-year OS <8 was 95.3%, 8–16 was 88.6% and >16 was 80%. mrNAR related to OS (HR 2.96, 95% CI 1.38–6.34, p = 0.005) and RFS (HR 2.99, 95% CI 1.49–6.00, p = 0.002). 3-year OS for mrNAR <8 was 96.2%, 8–16 was 92.4% and >16 was 78%. On multivariate analysis, mrNAR was a stage-independent predictor of OS and RFS. mrNAR corresponded to NAR score category in only 15% (positive predictive value 0.23) and 47.5% (positive predictive value 0.48) of cases for categories <8 and >16, respectively.

Conclusions

Neoadjuvant rectal score is validated as a surrogate end-point for long-term outcomes. mrNAR categories do not correlate with NAR but have stage-independent prognostic value. mrNAR may represent a novel surrogate end-point for future neoadjuvant treatments that focus on organ preservation.  相似文献   
59.

Purpose

Central to the use of murine models of disease is the ability to derive reproducible data. The purpose of this study was to determine factors contributing to variability in our murine model of small bowel resection (SBR).

Methods

Male C57Bl/6 mice were randomized to sham or 50% SBR. The effect of housing type (pathogen-free vs standard housing), nutrition (reconstituted powder vs tube feeding formulation), and correlates of intestinal morphology with gene expression changes were investigated. Multiple linear regression modeling or 1-way analysis of variance was used for data analysis.

Results

Pathogen-free mice had significantly shorter ileal villi at baseline and demonstrated greater villus growth after SBR compared to mice housed in standard rooms. Food type did not affect adaptation. Gene expression changes were more consistent and significant in isolated crypt cells that demonstrated adaptive growth when compared with crypts that did not deepen after SBR.

Conclusion

Maintenance of mice in pathogen-free conditions and restricting gene expression analysis to individual animals exhibiting morphologic adaptation enhances sensitivity and specificity of data derived from this model. These refinements will minimize experimental variability and lead to improved understanding of the complex process of intestinal adaptation.  相似文献   
60.
The treatment of Klebsiella pneumoniae, particularly extended-spectrum β-lactamase (ESBL)-producing K. pneumoniae, is currently a great challenge. Photodynamic antimicrobial chemotherapy is a promising approach for killing antibiotic-resistant bacteria. The aim of this study was to evaluate the capacity of 5-aminolevulinic acid (5-ALA) and its derivative 5-ALA methyl ester (MAL) in the presence of white light to cause photodynamic inactivation (PDI) of K. pneumoniae planktonic and biofilm cells. In the presence of white light, 5-ALA and MAL inactivated planktonic cells in a concentration-dependent manner. Biofilms were also sensitive to 5-ALA and MAL-mediated PDI. The mechanisms by which 5-ALA and MAL caused PDI of ESBL-producing K. pneumonia were also investigated. Exposure of K. pneumonia to light in the presence of either 5-ALA or MAL induced cleavage of genomic DNA and the rapid release of intracellular biopolymers. Intensely denatured cytoplasmic contents and aggregated ribosomes were also detected by transmission electron microscopy. Scanning electron microscopy showed that PDI of biofilms caused aggregated bacteria to detach and that the bacterial cell envelope was damaged. This study provides insights into 5-ALA and MAL-mediated PDI of ESBL-producing K. pneumoniae.  相似文献   
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