The role of magnetic resonance cholangiopancreatography in patients with suspected biliary obstruction

Endoscopic retrograde cholangiopancreatography (ERCP) is an accepted and accurate procedure that combines the advantage of diagnosis of biliary obstruction with possible therapeutic endobiliary intervention. However, it is an operator-dependent and invasive procedure that is associated with complications and limitations. Magnetic resonance cholangiopancreatography (MRCP) is a unique noninvasive technique for the diagnosis of biliary obstruction. It is well suited to provide the information required to plan the optimal therapeutic approach for these patients. MRCP has the potential to replace or at least precede ERCP as the first-line imaging effort in the evaluation of suspected biliary obstruction. Significant advantages and some notable limitations inherent to the modality dictate its judicious use in appropriate circumstances. The present article reviews the utility of MRCP in evaluation of biliary obstruction, with brief reference to its principles and techniques.     

Novel Tcradiolabeled quinazolinone derivative [Qn-In]: synthesis, evaluation and biodistribution studies in mice and rabbit

A quinazolinone derivative as a novel non-peptidic CCK-B receptor antagonist designated as Qn-In, was synthesized, characterized by spectroscopic techniques and evaluated for radiopharmaceutical potential. The efficiency of labeling with ^99mTc was greater than 98% and the complex was stable for about 7 hours at 37°C in presence of serum. Affinity of Qn-In was determined to be in nanomolar range by competitive binding studies on cancer cell line MDA-MB-468. Bio-distribution of ^99mTc labeled Qn-In in mice was examined by intravenous administration and time-activity curves were generated. The ligand showed binding to most of the organs, known to express CCK-B receptor. The lack of uptake in brain may be due to the inability of the complex to cross the blood-brain barrier. Our results show that ^99mTc labeled Qn-In ligand provides a new template for further development of non-peptidic ligands for diagnosis and therapy of diseases related with CCK-B receptor.     

Bladder rehabilitation in spinal cord injury patients.

The relative efficacy of intermittent catheterisation, self or assisted, over indwelling catheterisation was studied on 44 patients of different extent of spinal cord lesions. All the surviving cases (9) of incomplete cord lesion became catheter free irrespective of the method of catheterisation. In these patients urine was also found to be infection free by the 5th week of admission. Twenty-seven cases of complete cord lesion (out of a total of 35) became catheter free, of whom 18 patients were on intermittent catheterisation (out of a total of 20) and 9 patients were on indwelling catheter (out of a total of 15 cases). In the later group incidence of urine infection was higher. Other complications like urethral trauma were comparable between patients with indwelling catheter and patients with intermittent, self or assisted, catheterisation.     

Purulent meningitis in infancy and childhood

Summary 196 cases of purulent meningitis were studied. The history of aetiological factors was taken. Most of the cases presented with high fever and a classical picture of meningitis. C.S.F. was under tension in 176 cases and frank pus was observed in three cases. Polymorphonuclear leucocytosis was detected in all the C.S.F. specimens. Bacterial culture was done in 127 cases and organisms could be detected in 70. Despite some complications, viz. brain abscess, mastoid abscess and hydrocephalus, final recovery was good. The mortality was high in those cases who were admitted with acute illness and marked toxaemia. From the Department of Paediatrics. S.N. Medical College, Agra Paper read at 36th U.P. State Conlerence of Indian Medical Association, Aligarh, 1971.     

Degradation of diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] in cows

Five dairy cows were fed 0–50 ppm diuron herbicide [3-(3,4-dichlorophenyl)-1,1-dimethylurea] for 33 days and samples of milk, blood, urine, and feces were collected at regular intervals during the experiment. Approximately 50% of the diuron was recovered in urine, 10% in feces, and 5% in blood. No herbicide was detected in milk. In general, there was a positive correlation in the concentration of diuron products between urine and blood and a negative correlation between urine and feces. However, the percentage excretion of diuron residues in urine, feces, or blood was consistent in all treatments. The remaining > 35% of diuron, which was not detected, could have been absorbed in the body or degraded into undetectable metabolites. Two diuron metabolites, 3-(3,4-dichlorophenyl)-1-methylurea (DCMU) and 3-(3,4-dichlorophenyl)urea (DCU), were identified and determined only in urine from animals treated with 25 and 50 ppm due to experimental difficulties. Moreover, DCMU and DCU accounted for 8 and 25%, respectively, of diuron intake.     

Modulation of P-glycoprotein-mediated multidrug resistance in K562 leukemic cells by indole-3-carbinol

Resistance to chemotherapeutic drugs is one of the major problems in the treatment of cancer. P-glycoprotein (P-gp) encoded by the mdr gene is a highly conserved protein, acts as a multidrug transporter, and has a major role in multiple drug resistance (MDR). Targeting of P-gp by naturally occurring compounds is an effective strategy to overcome MDR. Indole-3-carbinol (I3C), a glucosinolates present in cruciferous vegetables, is a promising chemopreventive agent as it is reported to possess antimutagenic, antitumorigenic, and antiestrogenic properties in experimental studies. In the present investigation, the potential of I3C to modulate P-gp expression was evaluated in vinblastine (VBL)-resistant K562 human leukemic cells. The resistant K562 cells (K562/R10) were found to be cross-resistant to vincristine (VCR), doxorubicin (DXR), and other antineoplastic agents. I3C at a nontoxic dose (10 x 10(-3) M) enhanced the cytotoxic effects of VBL time dependently in VBL-resistant human leukemia (K562/R10) cells but had no effect on parent-sensitive cells (K562/S). The Western blot analysis of K 562/R 10 cells showed that I3C downregulates the induced levels of P-gp in resistant cells near to normal levels. The quantitation of immunocytochemically stained K562/R10 cells showed 24%, 48%, and 80% decrease in the levels of P-gp by I3C for 24, 48, and 72 h of incubation. The above features thus indicate that I3C could be used as a novel modulator of P-gp-mediated multidrug resistance in vitro and may be effective as a dietary adjuvant in the treatment of MDR cancers.     

A unique method by which to quantitate synchrony with equilibrium radionuclide angiography

Background

Cardiac resynchronization therapy (CRT) improves symptoms and the survival rate in patients with advanced heart failure by improving synchrony. However, CRT is not always successful, is costly, and is applied without individualization. There is no specific measure of synchrony. The goal of this study was to analyze new quantitative parameters of synchrony and compare them with established measures.

Methods and Results

Equilibrium radionuclide angiography, phase angle (Ø), and amplitude quantitate regional contraction timing and magnitude and are the basis for new synchrony (S) and entropy (E) parameters. S is the vector sum of all amplitudes based on the angular distribution of Ø divided by the scalar sum of the length of all vectors. Complete S equals 1, and its absence equals 0. E measures the disorder in the region of interest, is 1 with random contraction and 0 with full synchrony, and differentiates among differing contraction patterns. Left ventricular S and E were measured in 22 normal equilibrium radionuclide angiography studies, where regions of interest were drawn from the left ventricle, left atrium, and background to analyze model ventricles with normal wall motion (N), ventricles with aneurysm (An), ventricles with severe diffuse dysfunction (Diff), and ventricles with severe regional dysfunction (Reg). The new S and E parameters were highly reproducible and well differentiated among N, An, Diff, and Reg, which were not separated by SD Ø (SD of ventricular phase), which has gained popularity as a measure of synchrony.

Conclusion

Unique scintigraphic parameters for the evaluation of ventricular synchrony were derived, and their added value was determine compared with established measures.Indications for pacemaker therapy now include the treatment of severe congestive heart failure (CHF). Atrial triggered biventricular pacemakers reduce CHF symptoms¹ and prolong life² in patients with cardiomyopathy, severe CHF, left ventricular (LV) ejection fraction (EF) lower than 35%, and QRS greater than 120 milliseconds. Such pacing, or cardiac resynchronization therapy (CRT), seeks to reduce the heterogeneity and increase the synchrony of ventricular activation, conduction, and contraction. CRT has improved hemodynamics, increased exercise tolerance, reduced symptoms and the need for hospitalization,^1,32 reversed ventricular remodeling, and^4,5 reduced the all-cause mortality rate² in CHF. However, CRT is costly, fails to improve symptoms or activity level in more than 30% of patients,^2,3,6 and is applied blindly without individualization or consideration of lead placement sight.⁷A variety of echocardiographic methods have sought to measure synchrony and its serial changes with CRT.^4,8-16 A recent study presented evidence of the poor reproducibility of several widely applied echocardiographic measurements by which to determine ventricular synchrony.¹⁷ Magnetic resonance imaging has excellent resolution of regional wall motion and has been applied to assess ventricular synchrony and its response to pacing therapy.¹⁸ However, these methods are complex and are not well established or widely available, and magnetic resonance imaging has not been widely applied after pacing. An accurate and reproducible method is needed by which to objectively measure regional ventricular synchrony.¹⁹Phase image analysis, a functional method based on the first Fourier harmonic fit of the gated blood pool time versus radioactivity curve, generates the parameters of amplitude (A), which parallels the extent of regional ventricular contraction or stroke volume, and phase angle (Ø), which represents the timing of regional contraction. It was applied early with demonstrated reproducibility²⁰ to show the linkage between electrical and mechanical dyssynchrony21 and to characterize the contraction pattern in heart failure and its alteration with CRT.^22,23 The SD of ventricular Ø, applied as a marker of synchrony, has been shown to demonstrate the beneficial effects of biventricular pacing,²⁴ and its strong prognostic value has been shown in patients with congestive cardiomyopathy and CHF, superior to LVEF.²⁵ The SD Ø may not be optimal for synchrony evaluation.We sought improved, more sensitive parameters to better differentiate synchrony among the spectrum of possible patterns of dyssynergy. We derived, initially evaluated, and here present new synchrony (S) and entropy (E) parameters, based on the phase method, to quantitate regional and global ventricular synchrony and applied them in simulation and clinical protocols.