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1.
Josh Greenstein Devjani Das Josie Acuna Monica Kapoor Cara Brown Abbas Husain Brendan Lally Barry Hahn 《The American journal of emergency medicine》2019,37(2):313-316
Background
In the emergency department, rib fractures are a common finding in patients who sustain chest trauma. Rib fractures may be a sign of significant, underlying pathology, especially in the elderly patients where rib fractures are associated with significant morbidity and mortality. To date, no studies have evaluated the ability of ultrasound to detect rib fractures using cadaver models and subsequently use this model as a teaching tool.Objectives
The purpose of this study was to determine if it is possible to generate rib fractures on cadaver models which could be accurately identified using ultrasound.Methods
This was a cross-sectional study performed during one session at a cadaver lab. A single hemithorax from four adult cadavers were used as models. Single rib fractures on each of rib five through eight were created. Four subjects, blinded to the normal versus fractured ribs, were asked to identify the presence of a fracture on each rib.Results
A total of 8 of 16 potential ribs had fractured induced by study staff. Mean accuracy was 55% for all subjects. The overall sensitivity and specificity for detecting rib fractures was 50% (CI: 31.89–68.11) and 59.38% (CI: 35.69–73.55) respectively. The overall PPV and NPV was 55.17% and 54.29% respectively.Conclusions
In this pilot study, subjects were not able to detect induced rib fractures using ultrasound on cadaver models. The use of this model as a teaching tool in the detection of rib fractures requires further investigation. 相似文献2.
Palat Balachandran M.S. M.Ch. Shaleen Agarwal M.S. M.Ch. Narendra Krishnani M.D. Chandra M. Pandey Ph.D. Ashok Kumar M.S. M.Ch. Sadiq S. Sikora M.S. Rajan Saxena M.S. Vinay K. Kapoor M.S. 《Journal of gastrointestinal surgery》2006,10(6):848-854
The aim of this study was to examine the predictors of long-term survival (>24 months) in patients with gall bladder cancer.
A retrospective review of 117 cases of gall bladder cancer resected between 1989 and 2000. The resections included 80 simple
cholecystectomies and 37 extended procedures. Patients with survival >24 months (n=44) were compared with those having survival
<24 months (n=73) for 17 prognostic factors. Overall median survival was 16 months with a 5-year survival of 27%. T status
(P=.000) and adjuvant chemoradiotherapy (P=.001) were independent predictors of long-term survival. Survival advantage was
seen in T3N+ve disease (P=.007) with extended procedures. Complete (R0) resection was attained in 30 patients with a 5-year
survival advantage of 30% as compared with incomplete (R1) resection (P=.0002). Adjuvant chemoradiotherapy improved survival
in simple cholecystectomy group (P=.0008) but no advantage was seen after extended procedures. Stage III (P=.001) and node-positive
disease (P=.0005) had significant benefit with adjuvant therapy. Poor differentiation and vascular invasion were associated
with poor long-term survival. R0 resection was associated with prolonged survival. Extended procedures improved survival in
patients with T3N+ve disease. Addition of chemoradiotherapy made significant improvement in long-term survival in stage III
and node-positive lesions and in patients undergoing simple cholecystectomy. R0 resection predicted long-term survival in
gall bladder cancer. T3 N+ve disease had better survival after extended procedures. Adjuvant chemoradiotherapy improved survival
in stage III and node-positive disease. Poor differentiation and vascular invasion were adverse predictors of survival. 相似文献
3.
A case of Ewing's tumour of rib presenting as chest mass is reported. The role of computed tomography and chest ultrasound in evaluating such patients is discussed along with a brief review of literature. 相似文献
4.
Leeta Alison Green Khoi Nguyen Bijan Berenji Meera Iyer Eileen Bauer Jorge R Barrio Mohammad Namavari Nagichettiar Satyamurthy Sanjiv S Gambhir 《Journal of nuclear medicine》2004,45(9):1560-1570
Reporter probe 9-(4-18F-fluoro-3-[hydroxymethyl]butyl)guanine (18F-FHBG) and reporter gene mutant herpes simplex virus type 1 thymidine kinase (HSV1-sr39tk) have been used for imaging reporter gene expression with PET. Current methods for quantitating the images using the percentage injected dose per gram of tissue do not distinguish between the effects of probe transport and subsequent phosphorylation. We therefore investigated tracer kinetic models for 18F-FHBG dynamic microPET data and noninvasive methods for determining blood time-activity curves in an adenoviral gene delivery model in mice. METHODS: 18F-FHBG (approximately 7.4 MBq [approximately 200 microCi]) was injected into 4 mice; 18F-FHBG concentrations in plasma and whole blood were measured from mouse heart left ventricle (LV) direct sampling. Replication-incompetent adenovirus (0-2 x 10(9) plaque-forming units) with the E1 region deleted (n = 8) or replaced by HSV1-sr39tk (n = 18) was tail-vein injected into mice. Mice were dynamically scanned using microPET (approximately 7.4 MBq [approximately 200 microCi] 18F-FHBG) over 1 h; regions of interest were drawn on images of the heart and liver. Serial whole blood 18F-FHBG concentrations were measured in 6 of the mice by LV sampling, and 1 least-squares ratio of the heart image to the LV time-activity curve was calculated for all 6 mice. For 2 control mice and 9 mice expressing HSV1-sr39tk, heart image (input function) and liver image time-activity curves (tissue curves) were fit to 2- and 3-compartment models using Levenberg-Marquardt nonlinear regression. The models were compared using an F statistic. HSV1-sr39TK enzyme activity was determined from liver samples and compared with model parameter estimates. For another 3 control mice and 6 HSV1-sr39TK-positive mice, the model-predicted relative percentage of metabolites was compared with high-performance liquid chromatography analysis. RESULTS: The ratio of 18F-FHBG in plasma to whole blood was 0.84 +/- 0.05 (mean +/- SE) by 30 s after injection. The least-squares ratio of the heart image time-activity curve to the LV time-activity curve was 0.83 +/- 0.02, consistent with the recovery coefficient for the partial-volume effect (0.81) based on independent measures of heart geometry. A 3-compartment model best described 18F-FHBG kinetics in mice expressing HSV1-sr39tk in the liver; a 2-compartment model best described the kinetics in control mice. The 3-compartment model parameter, k3, correlated well with the HSV1-sr39TK enzyme activity (r2 = 0.88). CONCLUSION: 18F-FHBG equilibrates rapidly between plasma and whole blood in mice. Heart image time-activity curves corrected for partial-volume effects well approximate LV time-activity curves and can be used as input functions for 2- and 3-compartment models. The model parameter k3 from the 3-compartment model can be used as a noninvasive estimate for HSV1-sr39TK reporter protein activity and can predict the relative percentage of metabolites. 相似文献
5.
D. Le Elizabeth Eric R. Powers Jian-Ping Bin Howard Leong-Poi N. Craig Goodman Sanjiv Kaul 《Journal of nuclear cardiology》2007,14(2):207-214
Background The mechanism by which transmyocardial revascularization (TMR) offers clinical benefit is controversial. We hypothesized that
TMR ameliorates ischemia by reversing paradoxical catecholamine-induced vasoconstriction.
Methods and Results Chronic ischemic cardiomyopathy was created in 11 dogs by placing ameroid constrictors on the proximal coronary arteries and
their major branches. Six weeks later, 35 channels were created percutaneously in the left circumflex artery region, with
the left anterior descending artery region serving as control. At rest, wall thickening and myocardial blood flow did not
change in the treated region, whereas they deteriorated in the control bed. Contractile and myocardial blood flow reserve
increased in the treated region but deteriorated in the control region. There was diminished iodine 123 metaiodobenzylguanidine
uptake and a significant reduction in noradrenergic nerves in the treated region compared with the control region, with a
corresponding reduction in tissue tyrosine hydroxylase activity.
Conclusions We conclude that the absence of a catecholamine-induced reduction in MBF reserve and contractile reserve in the TMR-treated
region with associated evidence of neuronal injury indicates that the relief of exercise-induced ischemia after TMR most likely
results from reversal of paradoxical catecholamine-induced vasoconstriction. These findings may have implications in selecting
patients who would benefit from TMR.
Supported in part by grants from the National Institutes of Health (R01-HL66034 and K-08-HL074290-01). Bethesda. Md. The radio-labeled
microspheres were provided by DuPont Pharmaceuticals, North Billerica. Mass, and the ultrasound equipment was supplied by
Philips. Andover, Mass. Dr Leong-Poi was the recipient of a Fellowship Training Grant from the Canadian Institute of Health
Research and the Heart and Stroke Foundation of Canada. 相似文献
6.
The binding of racemic warfarin, its enantiomers, and several nonsteroidal anti-inflammatory agents to human serum albumin was investigated by equilibrium dialysis at 4 degrees C in pH 7.4 phosphate buffer. The primary binding constant for the S(-) enantiomer of warfarin was approximately two times greater than the corresponding binding of the R(+) enantiomer. The effect of azapropazone, phenylbutazone, naproxen, ibuprofen, mefenamic acid, and tolmetin on the binding of racemic warfarin and its enantiomers was studied. Warfarin was displaced by all of the nonsteroidal anti-inflammatory agents except tolmetin. Azapropazone caused the largest displacement of warfarin (39 to 46% free warfarin versus 2.5 to 6% free warfarin without competing drug), followed by phenylbutazone (23 to 43% free warfarin), naproxen (9 to 24% free warfarin), mefenamic acid (5 to 11.5% free warfarin), and ibuprofen (5 to 9% free warfarin). Azapropazone and phenylbutazone competed with warfarin for the same primary binding site on the albumin molecule. Naproxen appeared to affect warfarin binding at both primary and secondary sites. Ibuprofen and mefenamic acid interfered with the binding of warfarin at its secondary sites. In contrast to the other drugs studied, tolmetin caused an increase in the primary binding constant of warfarin. Structural analysis indicated that a common feature of those compounds which primarily bind at the warfarin site is a hydrophobic area bearing a widely delocalized negative charge. 相似文献
7.
8.
9.
R. Kapoor R. Pradeep S. S. Sikora R. Saxena V. K. Kapoor S. P. Kaushik 《ANZ journal of surgery》1994,64(9):599-603
One hundred and ten patients with common bile duct (CBD) stones were treated in the Department of Surgical Gastroenterology at SGPGIMS, Lucknow, India between January 1989 and December 1992. The primary modality of treatment was surgery in 62 patients (group I) and endoscopic sphincterotomy (ES) in 48 (group II). The two groups were well matched with respect to clinical features and presence of medical risk factors. Surgical clearance of CBD stones was achieved in 58 patients (93.5%; group Ia). Four patients (7%) had retained stones following surgery (group Ib). In group II, the CBD was cleared by endoscopic means in 20 out of 48 patients (42%) and was categorized into group IIa. In the remaining patients ES was followed by CBD exploration (group IIb). Significantly higher morbidity was seen in patients needing CBD surgery following attempted endoscopic clearance, because of ES-related complications, such as bleeding, cholangitis, septicaemia and numerous others. Use of ES to treat CBD stones on a routine basis was therefore not found to be any better than one-time surgical exploration. 相似文献
10.
Jane Avery Serene Manzar Ashtari Philip R Szeszko Sanjiv Kumra 《Revue canadienne de psychiatrie》2007,52(3):135-145
OBJECTIVES: To critically review and integrate, from a developmental perspective, recent magnetic resonance imaging (MRI) studies of 4 childhood psychiatric disorders: schizophrenia, bipolar disorder (BD), attention-deficit hyperactivity disorder (ADHD), and major depressive disorder (MDD). METHOD: We reviewed published reports in refereed journals. We briefly describe the major findings with respect to the brain morphometry, chemistry, and function of children with psychiatric disorders and synthesize the reports in a summary to update clinicians. RESULTS: Some cortical grey matter abnormalities associated with schizophrenia appear to predate the onset of frank psychosis and continue to advance after the onset of psychosis, at least in more severe cases. Pediatric BD is associated with abnormalities in a circuit, thought to be involved in mood regulation, that encompasses the amygdala, striatum, and ventral PFC. Frontostriatal abnormalities are reported consistently in ADHD, potentially reflecting abnormalities in the development of cognitive control. Children with MDD show prefrontal cortical alterations that may differ in familial and nonfamilial subtypes of MDD. CONCLUSIONS: Results from neuroimaging studies of childhood psychopathology reveal abnormalities in the developmental trajectories observed in healthy children. Although MRI has increased our understanding of the pathophysiology of these disorders, routine neuroimaging for children with severe emotional disturbances is not indicated for diagnostic purposes. 相似文献