Initial diagnosis of small lymphocytic lymphoma in parotidectomy for Warthin tumour, a rare collision tumour

Warthin tumours (WT) and malignant lymphomas are only rarely associated, and most are examples of involvement of the lymphoid stroma of WT by a disseminated lymphoma. This report describes a case where excision of a parotid mass led to the initial diagnosis of WT and small lymphocytic lymphoma (SLL). The diagnosis of SLL was confirmed by immunohistochemistry and molecular studies. The patient had stage IV A disease and is currently in chemotherapy induced complete remission. This case highlights the extremely rare association of SLL with WT and the importance of evaluation of the WT stroma, where the pale proliferation centres of SLL may mimic germinal centres of reactive lymphoid nodules.

Ion channels as important targets for antiepileptic drug design

Ion channels have a critical role in the function of the nervous system, where they instigate and conduct nerve impulses by asserting control over the voltage potential across the plasma membrane. Propagation of electrical impulses occurs by opening of voltage-gated ion channels. Ion channel blockers prevent this from occurring, and can therefore be used in the treatment of central nervous system disorders and neuropathic pain. Recent identification of ion channel gene mutations in Mendelian epilepsies suggests that genetically driven neuronal hyperexcitability plays an important role in epileptogenesis. Studies with animal seizure models have indicated that changes in temporal and spatial expression of voltage-gated sodium channels may be important in the pathology of epilepsy. This paper is aimed at elucidating the organization of the ion channels and covers a review on the antiepileptic drugs, both established and currently under development targeted to the ion channels in order to bring about effective seizure control.

Clonal B cell populations in a minority of patients with Hashimoto's thyroiditis

BACKGROUND

Hashimoto's thyroiditis (HT) is a risk factor for thyroid lymphoma, and clonal B cell populations in HT support this link. The literature on B cell clonality in HT is controversial.

AIMS

To identify clonal B cell populations in HT and to assess their usefulness in differentiating HT from mucosa associated lymphoid tissue (MALT) lymphoma and predicting future development of lymphoma.

METHODS

DNA from formalin fixed, paraffin wax embedded blocks of thyroid specimens from 10 patients with HT and two thyroid MALT lymphomas was analysed for B cell clonality by seminested polymerase chain reaction (PCR) using FRIII/LJH and FRIII/VLJH primers to amplify the IgH gene VDJ region. In one case, PCR products were sequenced. Immunohistochemistry was performed by labelled streptavidin-biotin technique using antibodies to: CD45, CD45RO, CD3, CD20, and cytokeratin.

RESULTS

The histopathological and clinical findings were characteristic of HT. Clonal bands were seen in three and a polyclonal smear pattern was seen in seven cases. The clonal bands in HT were associated with a background smear, and could not be reproduced from other blocks from the same case or from deeper sections of the same block. The clonal bands in thyroid lymphomas were not associated with a background smear and were reproducible. None of the patients with clonal B cells has developed malignant lymphoma during a follow up of 10-13 years.

CONCLUSIONS

B cell clonal bands in HT have different features from those in lymphoma (non-pure and non-reproducible) and do not predict future development of lymphoma.

The influence of solvent composition on global dynamics of human butyrylcholinesterase powders: a neutron-scattering study

A major result of incoherent elastic neutron-scattering experiments on protein powders is the strong dependence of the intramolecular dynamics on the sample environment. We performed a series of incoherent elastic neutron-scattering experiments on lyophilized human butyrylcholinesterase (HuBChE) powders under different conditions (solvent composition and hydration degree) in the temperature range from 20 to 285 K to elucidate the effect of the environment on the enzyme atomic mean-square displacements. Comparing D(2)O- with H(2)O-hydrated samples, we were able to investigate protein as well as hydration water molecular dynamics. HuBChE lyophilized from three distinct buffers showed completely different atomic mean-square displacements at temperatures above approximately 200 K: a salt-free sample and a sample containing Tris-HCl showed identical small-amplitude motions. A third sample, containing sodium phosphate, displayed highly reduced mean-square displacements at ambient temperature with respect to the other two samples. Below 200 K, all samples displayed similar mean-square displacements. We draw the conclusion that the reduction of intramolecular protein mean-square displacements on an Angstrom-nanosecond scale by the solvent depends not only on the presence of salt ions but also on their type.

Solitary wave interactions in dispersive equations using Manton's approach

We generalize the approach first proposed by Manton [Nucl. Phys. B 150, 397 (1979)] to compute solitary wave interactions in translationally invariant, dispersive equations that support such localized solutions. The approach is illustrated using as examples solitons in the Korteweg-de Vries equation, standing waves in the nonlinear Schrödinger equation, and kinks as well as breathers of the sine-Gordon equation.

Comparison of echo and MRI in the imaging evaluation of intracardiac masses

We compared the efficacy of echocardiography (ECHO) and magnetic resonance imaging (MRI) for evaluating intracardiac masses. Over an 8-yr period, 28 patients, 21 males, 7 females, 16 days-60 years of age (mean 25 years) with a suspected intracardiac mass on ECHO (transthoracic in all; transesophageal in 9) underwent an MRI examination. Five patients had a contrast-enhanced MRI. ECHO and MRI were compared with respect to their technical adequacy, ability to detect and suggest the likely etiology of the mass, and provide additional information (masses not seen with the other technique, inflow or outflow obstruction, and intramural component of an intracavitary mass). With MRI, the image morphology (including signal intensity changes on the various sequences) and extracardiac manifestations were also evaluated. The diagnosis was confirmed by histopathology in 18, surgical inspection in 4, by follow- up imaging on conservative management in 5, and by typical extracardiac manifestations of the disease in 1 patient. Fifteen (54%) patients had tumors (benign 12, malignant 3), 5 had a thrombus or hematoma, and 4 each had infective or vascular lesions. Thirty-four masses (13 in ventricle, 11 septal, 7 atrial, 2 on valve and 1 in pulmonary artery) were seen on MRI, 28 of which were detected by ECHO. Transthoracic ECHO (TTE) and MRI were technically optimal in 82% and 100% of cases, respectively. Nine patients needed an additional transesophageal ECHO (TEE). Overall, MRI showed a mass in all patients, whereas ECHO missed it in 2 cases. In cases with a mass on both modalities, MRI detected 4 additional masses not seen on ECHO. MRI suggested the etiology in 21 (75%) cases, while the same was possible with ECHO (TTE and TEE) in 8 (29%) cases. Intramural component, extension into the inflow or outflow, outflow tract obstruction, and associated pericardial or extracardiac masses were better depicted on MRI. We conclude that MRI is advantageous over a combination of TTE and TEE for the detection and complete morphological and functional evaluation (hemodynamic effects) of cardiac masses.

Antifilarial activity of Zoanthus species (Phylum Coelenterata, Class Anthzoa) against human lymphatic filaria, Brugia malayi

The chloroform methanol (1:1) extract of an unidentified green zoanthus (Phylum Coelenterata, Class Anthozoa) showed promising in vitro adulticidal activity with a lethal concentration of 125 microg/ml on Brugia malayi. This extract brought about a 52.2% reduction in circulating microfilariae of B. malayi when administered to infected Mastomys coucha at 250 mg/kg, orally for 5 consecutive days. Further fractionation of the extract led to the recovery of four fractions, which were evaluated simultaneously in both in vitro and in vivo systems against B. malayi. The chloroform fraction at 250 mg/kg orally for 5 days exhibited the highest macrofilaricidal action (42.5%), closely followed by the insoluble n-butanol fraction (34.3%), the soluble hexane fraction (32.4%), and the soluble n-butanol fraction (20.4%). In addition, the hexane soluble fraction caused 44.3% sterilization of the surviving female parasites. Two compounds isolated were found devoid of antifilarial activity.

Origin of magnetic and magnetoelastic tweedlike precursor modulations in ferroic materials

Based on experimental observations of modulated magnetic patterns in a Co0.5Ni0.205Ga0.295 alloy, we propose a model to describe a (purely) magnetic tweed and a magnetoelastic tweed. The former arises above the Curie (or Néel) temperature due to magnetic disorder. The latter results from compositional fluctuations coupling to strain and then to magnetism through the magnetoelastic interaction above the structural transition temperature. We discuss the origin of purely magnetic and magnetoelastic precursor modulations and their experimental thermodynamic signatures.

Rhizosphere dynamics influenced by arbuscular mycorrhizal fungus (Glomus deserticola) and related changes in leaf nutrient status and yield of Kinnow mandarin {King (Citrus nobilis) × Willow Leaf (Citrus deliciosa)}

Rhizosphere modification through root exudation is an important attribute that regulates not only the availability of nutrients in the soil but also their acquisition by plants. To test the above, 10-year-old Kinnow mandarin plants budded on Troyer citrange were inoculated with arbuscular mycorrhizal fungi (AMF) (Glomus deserticola) and Azotobacter chroococcum in different combinations with organic-farm-yard manure (FYM) and inorganic fertilisers in February when the root system was active. Plants with FYM alone were treated as a control. In the present investigation, a higher release of organic acids such as malic, citric, shikimic, and fumaric acids was evident from symbiotic roots of Kinnow inoculated with AMF (G. deserticola). Soil pH decreased significantly from 8.5 before the start of the experiment to 6.4 at the end of the experiment in the treatment where G. deserticola was applied with FYM. A decrease in soil EC and organic carbon, and an increase in soil availability of N, P, and K, leaf nutrient status, and fruit yield and quality were observed when the plants were inoculated with G. deserticola compared with all other treatments. This study indicates that G. deserticola, when compared with A. chroococcum, modifies the rhizosphere favourably to improve soil nutrient availability and consequent uptake by plants and thus result in better growth, fruit yield, and quality of Kinnow.

Breather lattice and its stabilization for the modified Korteweg-de Vries equation

We obtain an exact solution for the breather lattice solution of the modified Korteweg-de Vries equation. Numerical simulation of the breather lattice demonstrates its instability due to the breather-breather interaction. However, such multibreather structures can be stabilized through the concurrent application of ac driving and viscous damping terms.

The product of the imprinted gene IPL marks human villous cytotrophoblast and is lost in complete hydatidiform mole

The IPL/TSSC3 gene is expressed nearly exclusively from the maternal allele, and its protein product acts to limit placental growth in mice. This protein specifically marks Type II trophoblast in the labyrinthine layer of the mouse placenta. To investigate mouse-human homologies, we carried out immunohistochemistry with antibodies against human IPL. There was strong expression of IPL in villous cytotrophoblast of the human placenta, contrasting with complete lack of expression in syncytiotrophoblast. Staining for IPL was weak in cells of the villous mesenchyme and extravillous trophoblast, including the cytotrophoblast columns in the basal plate and the intervillous trophoblast islands. The IPL and p57(KIP2)/CDKN1C genes are closely linked and coordinately imprinted, and immunostaining showed that their protein products are co-expressed in villous cytotrophoblast. However, other cell types, including extravillous cytotrophoblast and cells in various non-placental tissues, expressed p57(KIP2), but not IPL. IPL protein was absent in both of two cases of androgenetic complete hydatidiform mole examined by immunostaining, and IPL mRNA was absent in an additional three cases of this neoplasm examined by northern blotting. In the mouse, Ipl-expressing cells disappear at mid- to late-gestation when placental growth ceases, but persistent IPL mRNA and protein expression was observed throughout human gestation, correlating with the continuous growth of the human placenta. These findings highlight dosage regulation of human IPL by imprinting and, more generally, suggest homology between Type II labyrinthine trophoblast in the mouse and villous cytotrophoblast in humans, both of which are proliferative stem cell-like compartments.

Drotaverine hydrochloride for augmentation of labor

OBJECTIVES

To study the use of drotaverine hydrochloride for acceleration of labor and relief of labor pains.

METHODS

In this double-blind placebo-controlled randomized study, 100 primigravidas in uncomplicated spontaneous labor at term were given drotaverine hydrochloride or placebo (distilled water) intramuscularly. Labor events, including pain (assessed by a visual analog scale and a verbal rating scale), neonatal outcome, and side effects of the drug were recorded. Student's t-test was used for analysis.

RESULTS

Forty-four patients in the drug group and 40 in the placebo group had complete data for analysis after decoding. In drotaverine group, there was a mean 15% reduction in the duration of the first stage of labor and a mean 19% reduction in the second stage. The maximum shortening of the first stage (28%) was observed when drotaverine was administered when cervical dilatation was 4 cm (P=0.044). There were no adverse fetal effects, but atonic postpartum hemorrhage was more common in the drotaverine group. There was no relief of pain with the drug except in the fourth stage of labor.

CONCLUSIONS

Drotaverine hydrochloride is safe and effective in accelerating labor, but not effective in lessening labor pain.

Molecular detection of the G(-248)A BAX promoter nucleotide change in B cell chronic lymphocytic leukaemia

BACKGROUND

A novel single nucleotide polymorphism (SNP), G(-248)A, in the 5' untranslated region of the BAX promoter and its association with reduced protein expression, progression beyond Rai stage 0, and treatment resistance in chronic lymphocytic leukaemia (CLL) has been reported previously.

AIM

To develop a restriction enzyme analysis (REA) based method for routine detection of BAX promoter SNP in a clinical laboratory.

METHODS

The BAX promoter was analysed in duplicate by REA and sequencing in 90 samples (from 45 patients with CLL, 43 controls, and two cell lines). The promoter region was amplified, digested with restriction endonucleases (Aci I and Tau I), and separated by gel electrophoresis.

RESULTS

After digestion, the normal GG genotype samples produced three distinct bands. The homozygous AA replacement abolished the cleavage site, resulting in a single band. Although the heterozygous samples produced three bands, the two smaller visible bands were reduced in intensity (> 50%). The test characteristics of Aci I REA were better than those of Tau I REA, in terms of sensitivity (100% v 77.8%), specificity (98.6% v 92.3%), positive predictive value (95.03% v 87.4%), and negative predictive value (100% v 85.83%).

CONCLUSIONS

REA using Aci I is a highly sensitive and specific method for detecting the BAX G(-248)A SNP in CLL.

Spin-polarized conductance induced by tunneling through a magnetic impurity

Using the zero mode method, we compute the conductance of a wire consisting of a magnetic impurity coupled to two Luttinger liquid leads characterized by the Luttinger exponent alpha(>or=1). We find for resonance conditions, in which the Fermi energy of the leads is close to a single particle energy of the impurity, that the conductance as a function of temperature is G approximately equal (e(2)/h)(T/T(F))(2(alpha-2)), whereas for off-resonance conditions the conductance is G approximately equal (e(2)/h)(T/T(F))(2(alpha-1)). By applying either a gate voltage or a magnetic field or both, one of the spin components can be in resonance while the other is off resonance causing a strong asymmetry between the spin-up and spin-down conductances.

Photoexcited breathers in conjugated polyenes: an excited-state molecular dynamics study

pi-conjugated polymers have become an important class of materials for electronic devices. Design of these devices requires understanding such processes as photochemical reactions, spatial dynamics of photoexcitations, and energy and charge transport, which in turn involve complex coupled electron-vibrational dynamics. Here we study nonlinear photoexcitation dynamics in the polyene oligomers by using a quantum-chemical method suitable for the simulation of excited-state molecular dynamics in extended molecular systems with sizes up to hundreds of atoms. The method is based on the adiabatic propagation of the ground-state and transition single-electron density matrices along the trajectory. The simulations reveal formation of a self-localized vibronic excitation ("breather" or multiquanta bound state) with a typical period of 34 fs and allows us to identify specific slow and fast nuclear motions strongly coupled to the electronic degrees of freedom. The effect of chain imperfections and chemical defects on the dynamics is also investigated. A complementary two-dimensional analysis of corresponding transition density matrices provides an efficient way to monitor time-dependent real-space localization of the photoexcitation by identifying the underlying changes in charge densities and bond orders. Possible correlated electronic and vibrational spectroscopic signatures of photoexcited breathers are predicted, and generalizations to energy localization in complex macromolecules are discussed.

Confinement of discrete breathers in inhomogeneously profiled nonlinear chains

We investigate numerically the scattering of a moving discrete breather on a pair of junctions in a Fermi-Pasta-Ulam chain. These junctions delimit an extended region with different masses of the particles. We consider (i) a rectangular trap, (ii) a wedge shaped trap, and (iii) a smoothly varying convex or concave mass profile. All three cases lead to DB confinement, with the ease of trapping depending on the profile of the trap. We also study the collision and trapping of two DBs within the profile as a function of trap width, shape, and approach time at the two junctions. The latter controls whether one or both DBs are trapped.

Pulmonary artery calcification in recipient twins of twin to twin transfusion syndrome: a report of three cases

Twin to twin transfusion syndrome may rarely complicate monochorionic twin gestation, resulting in discordant size of the twins. Cardiac dysfunction and various types of cardiac defects have been described in the recipient twin of this syndrome. Pulmonary artery calcification has been described earlier in one case only. We report three recipients of twin to twin transfusion syndrome with pulmonary artery calcification resulting in obstruction of pulmonary trunk in two of these. One case with progressive severe narrowing was successfully operated at four months of age with patch repair of pulmonary artery. He is doing well three years later. The obstruction is moderate in the other case. Calcification in the wall of pulmonary artery may be secondary to vascular injury sustained as a result of volume overloading of the circulation of the recipient twin.