Optimal site for fluoroscopic tracer injection for laparoscopic lymphadenectomy

Abstract Background Metabolic reprogramming is a common phenomenon in tumorigenesis and tumor progression. Amino acids are important mediators in cancer metabolism, and their kinetics in tumor tissue are far from being understood completely. Mass spectrometry imaging is capable to spatiotemporally trace important endogenous metabolites in biological tissue specimens. In this research, we studied L-[ring-13C6]-labeled phenylalanine and tyrosine kinetics in a human non-small cell lung carcinoma (NSCLC) xenografted mouse model using matrix-assisted laser desorption/ionization Fourier-transform ion cyclotron resonance mass spectrometry imaging (MALDI-FTICR-MSI). Methods We investigated the L-[ring-13C6]-Phenylalanine (13C6-Phe) and L-[ring-13C6]-Tyrosine (13C6-Tyr) kinetics at 10 min (n = 4), 30 min (n = 3), and 60 min (n = 4) after tracer injection and sham-treated group (n = 3) at 10 min in mouse-xenograft lung tumor tissues by MALDI-FTICR-MSI. Results The dynamic changes in the spatial distributions of 19 out of 20 standard amino acids are observed in the tumor tissue. The highest abundance of 13C6-Phe was detected in tumor tissue at 10 min after tracer injection and decreased progressively over time. The overall enrichment of 13C6-Tyr showed a delayed temporal trend compared to 13C6-Phe in tumor caused by the Phe-to-Tyr conversion process. Specifically, 13C6-Phe and 13C6-Tyr showed higher abundances in viable tumor regions compared to non-viable regions. Conclusions We demonstrated the spatiotemporal intra-tumoral distribution of the essential aromatic amino acid 13C6-Phe and its de-novo synthesized metabolite 13C6-Tyr by MALDI-FTICR-MSI. Our results explore for the first time local phenylalanine metabolism in the context of cancer tissue morphology. This opens a new way to understand amino acid metabolism within the tumor and its microenvironment.

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Streptococcal pharyngitis: Optimal site for throat culture

The Journal of Pediatrics ◽

10.1016/s0022-3476(85)80354-1 ◽

1985 ◽

Vol 106 (5) ◽

pp. 781-783 ◽

Cited By ~ 35

Author(s):

James H. Brien ◽

James W. Bass

Keyword(s):

Streptococcal Pharyngitis ◽

Throat Culture ◽

Optimal Site

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Renal function measurements from MR renography and a simplified multicompartmental model

AJP Renal Physiology ◽

10.1152/ajprenal.00347.2006 ◽

2007 ◽

Vol 292 (5) ◽

pp. F1548-F1559 ◽

Cited By ~ 107

Author(s):

Vivian S. Lee ◽

Henry Rusinek ◽

Louisa Bokacheva ◽

Ambrose J. Huang ◽

Niels Oesingmann ◽

...

Keyword(s):

Low Dose ◽

Random Noise ◽

Compartment Model ◽

Parameter Estimates ◽

Imaging Data ◽

Tracer Injection ◽

Multicompartmental Model ◽

Enhancement Curve ◽

Reference Measurements ◽

Single Kidney

The purpose of this study was to determine the accuracy and sources of error in estimating single-kidney glomerular filtration rate (GFR) derived from low-dose gadolinium-enhanced T1-weighted MR renography. To analyze imaging data, MR signal intensity curves were converted to concentration vs. time curves, and a three-compartment, six-parameter model of the vascular-nephron system was used to analyze measured aortic, cortical, and medullary enhancement curves. Reliability of the parameter estimates was evaluated by sensitivity analysis and by Monte Carlo analyses of model solutions to which random noise had been added. The dominant sensitivity of the medullary enhancement curve to GFR 1–4 min after tracer injection was supported by a low coefficient of variation in model-fit GFR values (4%) when measured data were subjected to 5% noise. These analyses also showed the minimal effects of bolus dispersion in the aorta on parameter reliability. Single-kidney GFR from MR renography analyzed by the three-compartment model (4.0–71.4 ml/min) agreed well with reference measurements from 99mTc-DTPA clearance and scintigraphy ( r = 0.84, P < 0.001). Bland-Altman analysis showed an average difference of 11.9 ml/min (95% confidence interval = 5.8–17.9 ml/min) between model and reference values. We conclude that a nephron-based multicompartmental model can be used to derive clinically useful estimates of single-kidney GFR from low-dose MR renography.

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Does Systematic Preliminar Colour Doppler Study Reduce Kidney Biopsy Complication Incidence?

International Journal of Nephrology ◽

10.4061/2011/419093 ◽

2011 ◽

Vol 2011 ◽

pp. 1-5

Author(s):

Antonio Granata ◽

Fulvio Floccari ◽

Angelo Ferrantelli ◽

Ugo Rotolo ◽

Luca Di Lullo ◽

...

Keyword(s):

Kidney Biopsy ◽

Colour Doppler ◽

Doppler Examination ◽

Doppler Study ◽

Group A ◽

Clinically Significant ◽

Perinephric Hematoma ◽

Group B ◽

Biopsy Complications ◽

Optimal Site

While ultrasonography is widely performed prior to biopsy, colour Doppler examination is often used only to discover post-biopsy complications. Aim of this paper was to evaluate the usefulness of colour Doppler examination in planning the optimal site of puncture for renal biopsy. Present analysis includes 561 consecutive percutaneous renal biopsies performed from the same operator. Until August 2000 332 biopsies were performed after a preliminary ultrasonography (Group A). From September 2000, 229 patients underwent even a preliminary colour Doppler study (Group B). Postbioptic bleeding were categorized as minor (gross hematuria or subcapsular perinephric hematoma < 4 cmq of greater diameter) or major (hematoma >4 cmq of greater diameter; requiring blood transfusion or invasive procedures; leading to acute renal failure, urine tract obstruction, septicaemia, or death). Major complications were seen in 2.1% in Group A while in Group B only one case was reported (0.43%). Minor clinically significant complications occur in 7.8% in Group A and in 3.4% of cases of Group B. Colour Doppler reduced drastically the incidence of complications observed before the introduction of routine colour Doppler examination prior to biopsy. In our opinion, these data support the use of preliminary colour Doppler study when a biopsy is planned.

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