Ximelagatran, the Oral Anticoagulant of the Future An Evidence Based Review

This article presents the available data on Ximelagatran, a novel oral direct thrombin inhibitor and explores its therapeutic potential Recent large clinical trials have evaluated the efficacy and safety of this anticoagulant compared to the standard anticoagulation therapy with warfarin and heparins in several thrombotic disorders. These trials provide strong evidence for the efficacy and safety of ximelagatran in the following clinical indications; the prevention of venous thromboembolism after knee or hip replacement, the treatment of deep venous thrombosis, and prevention of stroke in patients with atrial fibrillation. Further evaluation of this promising oral anticoagulant is warranted in other thrombotic cardiovascular disorders requiring chronic oral anticoagulation therapy such as in patients with prosthetic heart valves, intracardiac thrombi, dilated cardiomyopathy, after myocardial infarction and post percutaneous coronary interventions.

An Ab Initio and Density Functional Theory Study of Keto−Enol Equilibria of Hydroxycyclopropenone in Gas and Aqueous Solution Phase

Keto-enol tautomerism in hydroxycyclopropenone (2-hydroxy-2-cyclopropen-1-one) has been studied using ab initio methods, the B3LYP functional of density functional theory, as well as complete basis set (CBS-QB3 and CBS-APNO) and G3 methods. Absolute and relative energies were calculated with each of the methods, whereas computations of geometries and harmonic frequencies for hydroxycyclopropenone and 1,2-cyclopropanedione were computed in the gas phase but were limited to HF, MP2 and CCSD levels of theory, and the B3LYP functional, in combination with the 6-31++G** basis set. Using the MP2/6-31++G** gas phase optimized structure, each species was then optimized fully in aqueous solution by employing the polarizable continuum model (PCM) self-consistent reaction field approach, in which HF, MP2 and B3LYP levels of theory were utilized, with the same 6-31++G** basis set. In both gas and aqueous solution phases, the keto form is higher in energy for all of the model chemistries considered. The presence of the solvent, however, is found to have very little effect on the bond lengths, angles and harmonic frequencies. From the B3LYP/6-31++G** Gibbs free energy, the keto-enol tautomeric equilibrium constant for 2-hydroxy-2-cyclopropen-1-one <==> 1,2-cyclopropanedione is computed to be K(T)(gas) = 2.35 x 10(-6), K(T)(aq) = 5.61 x 10(-14). It is concluded that the enol form is overwhelmingly predominant in both environments, with the effect of the solvent shifting the direction of equilibrium even more strongly in the favor of hydroxycyclopropenone. The almost exclusive nature of this species is attributed to stabilization resulting from aromaticity. Confirmation is provided by comparison of the simulated vibrational spectra of hydroxycyclopropenone with the measured infrared spectrum in an argon matrix.

A general formula for the rate of resonant transfer of energy between two electric multipole moments of arbitrary order using molecular quantum electrodynamics

A general expression is derived for the matrix element for the resonant transfer of energy between an initially excited donor species and an acceptor moiety in the ground state, with each entity possessing an electric multipole moment of arbitrary order. In the quantum electrodynamical framework employed, the coupling between the pair is mediated by the exchange of a single virtual photon. The probability amplitude found from second-order perturbation theory is a product of the electric moments located at each center and the resonant multipole-multipole interaction tensor. Using the Fermi golden rule, a general formula for the rate of energy transfer is obtained. As an illustration of the efficacy of the theory developed, rates of excitation energy exchange are calculated for systems interacting through dipole-quadrupole, dipole-octupole, quadrupole-quadrupole, and the familiar dipole-dipole coupling. For each of the cases examined, the near- and far-zone limits of the migration rate are calculated from the result valid for all donor-acceptor separations beyond wave function overlap. Expression of the octupole contribution to the transfer rate in terms of its irreducible components of weights 1 and 3 leads to new features. The octupole weight-1 term is found to contribute only when the interaction is retarded, while the dipole-octupole weight-1 contribution appears as a higher-order correction term to the dipole-dipole rate. Order of magnitude estimates are given for the contributions of dipole-quadrupole and dipole-octupole terms relative to the leading dipole-dipole rate for near-, intermediate-, and far-zone separations to further understand the role played by higher multipole moments in the transfer of excitation and the mechanism dominating the process.

Resonant transfer of excitation between two molecules using Maxwell fields

The matrix element for the resonant transfer of excitation between two molecules possessing electric and magnetic multipole moments of arbitrary order is calculated using quantum electrodynamical response theory. A prerequisite of the method is the functional form for the lth order linear electric and magnetic multipole dependent electric displacement and magnetic field operators in the neighborhood of a molecule, whose derivation is also given. The initially unexcited species is viewed as a test body accepting energy resonantly via coupling to the Maxwell fields of the excited multipole source molecule. The generalized electric-electric multipole contribution to the matrix element is shown to agree with an earlier calculation using time-dependent perturbation theory. As an application involving both electric and magnetic terms, the rate of excitation transfer between two chiral molecules is computed and found to depend on the handedness of each species.

Extracellular Loop 3 (EL3) and EL3-Proximal Transmembrane Helix 7 of the Mammalian Type I and Type II Gonadotropin-Releasing Hormone (GnRH) Receptors Determine Differential Ligand Selectivity to GnRH-I and GnRH-II

Mammalian type I and II gonadotropin-releasing hormone (GnRH) receptors (GnRHRs) show differential ligand preference for GnRH-I and GnRH-II, respectively. Using a variety of chimeric receptors based on green monkey GnRHR-2 (gmGnRHR-2), a representative type II GnRHR, and rat GnRHR, a representative type I GnRHR, this study elucidated specific domains responsible for this ligand selectivity. A chimeric gmGnRHR-2 with the extracellular loop 3 (EL3) and EL3-proximal transmembrane helix 7 (TMH7) of rat GnRHR showed a great increase in ligand sensitivity to GnRH-I but not to GnRH-II. Point-mutation studies indicate that four amino acids, Leu/Phe(7.38), Leu/Phe(7.43), Ala/Pro(7.46), and Pro/Cys(7.47) in TMH7 are critical for ligand selectivity as well as receptor conformation. Furthermore, a combinatory mutation (Pro(7.31)-Pro(7.32)-Ser(7.33) motif to Ser-Glu-Pro in EL3 and Leu(7.38), Leu(7.43), Ala(7.46), and Pro(7.47) to those of rat GnRHR) in gmGnRH-2 exhibited an approximately 500-fold increased sensitivity to GnRH-I, indicating that these residues are critical for discriminating GnRH-II from GnRH-I. [Trp(7)]GnRH-I and [Trp(8)]GnRH-I but not [His(5)]GnRH-I exhibit a higher potency in activating wild-type gmGnRHR-2 than native GnRH-I, indicating that amino acids at positions 7 and 8 of GnRHs are more important than position 5 for differential recognition by type I and type II GnRHRs. As a whole, these data suggest a molecular coevolution of ligands and their receptors and facilitate the understanding of the molecular interaction between GnRHs and their cognate receptors.

Features distinguishing amoebic from pyogenic liver abscess: a review of 577 adult cases

Distinguishing amoebic from pyogenic liver abscesses is crucial because their treatments and prognoses differ. We retrospectively reviewed the medical records of 577 adults with liver abscess in order to identify clinical, laboratory, and radiographic factors useful in differentiating these microbial aetiologies. Presumptive diagnoses of amoebic (n = 471; 82%) vs. pyogenic (n = 106; 18%) abscess were based upon amoebic serology, microbiological culture results, and response to therapy. Patients with amoebic abscess were more likely to be young males with a tender, solitary, right lobe abscess (P = 0.012). Univariate analysis found patients with pyogenic abscess more likely to be over 50 years old, with a history of diabetes and jaundice, with pulmonary findings, multiple abscesses, amoebic serology titres <1:256 IU, and lower levels of serum albumin (P < 0.04). Multivariate logistic regression analysis confirmed that age >50 years, pulmonary findings on examination, multiple abscesses, and amebic serology titres <1:256 IU were predictive of pyogenic infection. Several clinical and laboratory parameters can aid in the differentiation of amebic and pyogenic liver abscess. In our setting, amebic abscess is more prevalent and, in most circumstances, can be identified and managed without percutaneous aspiration.

Quantum dynamics calculations using symmetrized, orthogonal Weyl-Heisenberg wavelets with a phase space truncation scheme. III. Representations and calculations

In a previous paper [J. Theo. Comput. Chem. 2, 65 (2003)], one of the authors (B.P.) presented a method for solving the multidimensional Schrodinger equation, using modified Wilson-Daubechies wavelets, and a simple phase space truncation scheme. Unprecedented numerical efficiency was achieved, enabling a ten-dimensional calculation of nearly 600 eigenvalues to be performed using direct matrix diagonalization techniques. In a second paper [J. Chem. Phys. 121, 1690 (2004)], and in this paper, we extend and elaborate upon the previous work in several important ways. The second paper focuses on construction and optimization of the wavelength functions, from theoretical and numerical viewpoints, and also examines their localization. This paper deals with their use in representations and eigenproblem calculations, which are extended to 15-dimensional systems. Even higher dimensionalities are possible using more sophisticated linear algebra techniques. This approach is ideally suited to rovibrational spectroscopy applications, but can be used in any context where differential equations are involved.

Quantum dynamics calculations using symmetrized, orthogonal Weyl-Heisenberg wavelets with a phase space truncation scheme. II. Construction and optimization

In this paper, we extend and elaborate upon a wavelet method first presented in a previous publication [B. Poirier, J. Theo. Comput. Chem. 2, 65 (2003)]. In particular, we focus on construction and optimization of the wavelet functions, from theoretical and numerical viewpoints, and also examine their localization properties. The wavelets used are modified Wilson-Daubechies wavelets, which in conjunction with a simple phase space truncation scheme, enable one to solve the multidimensional Schrodinger equation. This approach is ideally suited to rovibrational spectroscopy applications, but can be used in any context where differential equations are involved.

Maximum tolerable dose of cyclophosphamide and azathioprine in Pakistani patients with primary renal disease

OBJECTIVE

The immunosuppressive regimens, at present, mainly rely on western guidelines that were derived from studies conducted in western populations. No such study exists for South Asian population, which is home to almost two billion people different in both genetics and environment from west. Locally derived thresholds for side effects markedly different from western figures may warrant re-adjustment of current local immunosuppressive regimens that are at present based largely on western guidelines. In order to define optimum dose for Cyclophosphamide (CYC) and Azathioprine (AZA) based immunosuppressive therapy, we conducted this study to find out maximum tolerable doses of azathioprine (AZA) and cyclophosphamide (CYC) beyond which neutropenia and thrombocytepenia are most likely to occur in patients with primary renal pathology.

METHOD

Patients with systemic vasculitis and idiopathic glomerulonephritis who were on CYC and AZA were identified through review of medical records at a tertiary care hospital in Pakistan (The Aga Khan University Hospital, Karachi). Patients were categorized under three principal diagnosis i.e. systemic lupus erythematosus (SLE), primary (idiopathic) glomerulonephritis (GN) and Wegener's granulomatosis (WG). The Receiver Operating Curve (ROC) was used to calculate the maximum tolerable dose for both CYC and AZA.

RESULTS

We identified 94 patients aged 6-82 years (median 44.5 years) with primary renal disease (Wegener's granulomatosis n=13, Systemic lupus erythematosis n=62 and idiopathic glomerulonephritis n=19) who received CYC or AZA. Of these 94 patients, 36.2% (n=34) received CYC and 63.8% (n=60) received AZA. The mean dose of CYC was 1.54 +/- 0.50 mg/kg of body weight (range: 0.77-2.93). The mean dose of AZA was 1.64 +/- 0.59 mg/kg of body weight (range: 0.47-2.97). The maximum tolerable doses calculated for CYC and AZA were 1.25 mg/kg and 1.30 mg/kg of body weight respectively. The maximum tolerable dose for CYC and AZA among males could not be calculated, because of insufficient number of patients who developed neutropenia and thrombocytopenia. The maximum tolerable doses for CYC and AZA among females were 1.34 mg/kg and 1.03 mg/kg of body weight respectively. Also we found out that AZA was relatively more likely to cause neutropenia and thrombocytopenia (p=0.07).

CONCLUSION

We thereby recommend that CYC should be initiated at a dose no more than 1 mg/kg of body weight and AZA at an initial dose of 0.75-1.0 mg/kg of body weight. The dose may be adjusted later on the basis of clinical response and laboratory reports.

Outcome of adult acute lymphoblastic leukemia: a single center experience

OBJECTIVE

To study the outcomes of adult patients with acute lymphoblastic leukemia.

SETTING

Tertiary care hospital.

STUDY DESIGN

Retrospective analysis.

METHODS

Fifty eight adult patients (age >14 years) diagnosed as cases of acute lymphoblastic leukemia were studied with respect to their clinical, morphological and immunopathological features at presentation and their relationship with treatment outcomes.

RESULTS

Forty five (77.5%) of the patients belonged to younger age group with male preponderance. The median age was 20 years and mean age was 25.1 years. Male to female ratio was 3:1. Common presenting signs were lymphadenopathy (17.2%), hepatomegaly (32.7%) and splenomegaly (62%). Laboratory features at presentation revealed: hemoglobin > or = 10 gm/dl in 18 (31%), WBC >50 x 10E9 / L in 18 (31%), LDH more than 1000 IU/L in 44 (75.8%) of patients. Morphology revealed that FAB L1 was seen in 21(37.2%) and L2 in 62 (32.7%). Immunophenotyping showed that 26 (61.9%) were early pre-B ALL, 6 (14.2%) were pre-B ALL and T-ALL were 10 (23.8%). Univariate analysis showed age more than 30 years, male gender, total leucocyte count >50 x 10(9)/L and hemoglobin more than 10 gm/dl to be risk factors for poor outcome. Multivariate analysis revealed age more than 30 years, male sex and total leucocyte count > 50 x 10(9)/L are independent risk factors for poor survival. Patients were treated according to the MRCUKX and XII adult protocols. Thirteen (22.4%) patients died during induction therapy secondary to sepsis and progressive disease whereas 42 (72.4%) patients achieved complete remission. Median survival was 18.6 months and 42% patients were alive at 5-years.

CONCLUSION

Overall survival and disease free survival were comparable to those reported in literature. However, age more than 30 years, male gender and total leucocyte count >50 x 10(9)/L had an adverse impact on overall survival.

Aerosol chemical characteristics of an island site in the Bay of Bengal (Bhola-Bangladesh)

Aerosol constituents (elemental carbon, organic carbon, soluble ions including organic acids, and selected trace metals) were investigated from samples of a field campaign taking place at Bhola Island in the Bay of Bengal (Bangladesh). The campaign took place in the pre-monsoon season (May 2001) using low volume samplers. Carbonaceous material comprised the majority of the analysed components. The average concentrations of EC and OC were 2.8 and 4.6 microg m(-3), respectively. Oxalic acid was the most abundant dicarboxylic acid (average 268 ng m(-3)) followed by malonic and malic acid. The contribution of carboxylic acids-carbon to organic carbon was 2.0%. Average concentrations observed for sulfate and nitrate were 3.7 microg m(-3) and 1.5 microg m(-3). Two different types of aerosol were identified at the rural background site on Bhola Island during southerly synoptic flow by means of trajectory analysis: air masses were transported from the Bay of Bengal to the sampling site in all cases. However, during "Period 1" they experienced longer residence times over the Indian Ocean, while the "Period 2" trajectories came along the Indian coast or passed over the Indian continent. During Period 1 the concentration levels of soluble ions were a factor of 4-6 lower than during Period 2. The concentrations of EC, OC and K differed less than a factor of 1.5 between the two periods. The Period 1 aerosol showed similarities to the haze layers observed during winter-monsoon conditions south of India during the INDOEX experiment. Based on EC/TC and K/EC ratios we find that around 80% of the carbonaceous aerosol from Period 1 in Bhola is from fossil fuel and only around 50% from Period 2. Absolute concentrations of carbonaceous species, soluble ions and trace metals indicate that the background site on Bhola Island is affected by emissions from urbanized regions of Southeast Asia.

Congenital cystic adenomatoid malformation

This case report presents the clinical picture, diagnostic methodology and surgical treatment of a female child who presented with chronic cough and dyspnoea due to congenital malformation of lung. A discussion of diagnosis and management is presented at the end.

Flt3-L augments the engraftment of donor-derived bone marrow cells when combined with sublethal irradiation and costimulatory (CD28/B7 and CD40/CD40L) blockade

T-cell costimulatory blockade as a constituent for recipient conditioning prior to bone marrow transplantation has led to the development of less toxic protocols for the establishment of donor cell chimerism. We therefore hypothesized that the addition of the hematopoietic growth factor, Flt3-ligand (Flt3-L), to the perioperative inhibition of the CD28/B7 and CD40/CD40 ligand costimulatory pathways would enhance the engraftment of allogeneic bone marrow. Recipient BALB/c ByJ (H-2(d), Mls(c), Vbeta6+/Vbeta8+ TCR) received a single sublethal dose of total body irradiation (300 rad) 6 h prior to transplantation IV with unfractionated donor CBA/J (H-2(k), Mls(d), Vbeta6-/Vbeta8+ TCR) bone marrow cells. CTLA4-Ig and/or MRI were administered at 500 microg IP on days 0, 2, 4, and 6 posttransplantation. Flt3-L was administered at 10 microg IP on days 0-6. Donor cell chimerism was determined on days 30-90 by flow cytometric analysis. Donor-specific tolerance was assessed by skin grafting. In vitro TCR cross-linking assays and flow cytometry were utilized to explore the deletion of donor-reactive T cells. Recipients receiving CTLA4-Ig and MRI engrafted allogeneic bone marrow cells in the peripheral blood (3/6; 50%) with chimerism being detected at 2-31%. Addition of Flt3-L to this preconditioning regimen enhanced the incidence of engraftment of donor bone marrow cells (10/13; 3-70%). Long-term survival of donor but not third-party-specific skin grafts demonstrated that donor-specific tolerance had been achieved in the chimeric recipients. Deletion of the donor-reactive T cells within the chimeric recipients was also observed. The addition of hematopoietic growth factors and cytokines to the nonmyeloablative regimen of sublethal irradiation and T-cell costimulatory blockade provides a novel strategy for the establishment of donor cell chimerism and for the induction of stable and robust donor-specific tolerance. The deletion of donor-reactive T cells using this protocol suggests the reliability and feasibility of this protocol for clinical transplantation.

Factors which predict unsuccessful mobilisation of peripheral blood progenitor cells following G-CSF alone in patients with non-Hodgkin's lymphoma

INTRODUCTION

High-dose therapy with haematopoietic progenitor cell support has increasingly been utilised for patients with haematological malignancies. Peripheral blood is the stem cell source of choice, however, various mobilisation strategies are used by different centres.

PATIENTS AND METHODS

Over a 2-year period, 52 patients with non-Hodgkin's lymphoma (median age 47 years, range 16-64 years) underwent peripheral blood progenitor cell mobilisation using G-CSF alone (16 microg/kg/day). The harvest was considered successful if > or =1 x 10(6) CD34(+) cells/kg were collected by leukapheresis. The histological subtypes of non-Hodgkin's lymphoma comprised: follicular (24 patients), diffuse large B-cell (14 patients), lymphoplasmacytoid (four patients), mantle cell (three patients), lymphoblastic lymphoma (one patient) and small lymphocytic lymphoma/chronic lymphocytic leukaemia (six patients). The median interval from diagnosis of non-Hodgkin's lymphoma to mobilisation was 27 months (range 2 months to 17 years). The median number of prior treatment episodes was 2 (range 1-5); 26 patients had received fludarabine alone or in combination. At the time of peripheral blood progenitor cell mobilisation, 20 patients were in 1st remission and 32 were in > or =2nd remission; 30 patients were in partial remission and 22 were in complete remission; the bone marrow was involved in nine patients.

RESULTS

Peripheral blood progenitor cell mobilisation/harvest was unsuccessful in 19 out of 52 (37%) patients (mobilisation: 18, harvest: 1). The factors associated with unsuccessful mobilisation or harvest were: prior fludarabine therapy (P=0.002), bone marrow involvement at diagnosis (P=0.002), bone marrow involvement anytime prior to mobilisation (P=0.02), histological diagnosis of follicular, mantle cell, or lymphoplasmacytoid lymphoma, or small lymphocytic lymphoma/chronic lymphocytic leukaemia (P=0.03) and female gender (P=0.04).

CONCLUSION

Although peripheral blood progenitor cells can be successfully mobilised and harvested from the majority of patients with non-Hodgkin's lymphoma after treatment with G-CSF alone, the latter is unsuccessful in approximately one-third of patients. These factors should be taken into account when patients are being considered for high-dose treatment.

Clinical, pathological and molecular factors predicting axillary node involvement in primary breast cancer in Pakistani women

BACKGROUND

Axillary lymph node involvement in primary breast cancer is one of its most important prognostic features. Thus any factors that may predict axillary lymph node involvement in this setting could be potentially helpful in treatment planning and other interventions.

OBJECTIVE

The objective of this study was to evaluate clinical, pathological and immuno-histochemical markers in univariate and multivariate analysis, which may be helpful predictors of axillary lymph node involvement in breast cancer.

METHOD

A retrospective analysis of 555 cases. Of these 58% had axillary nodal positivity and 42% were negative.

CONCLUSION

Factors of no significance included patient's age, height, weight, age of first pregnancy, parity, marital status, menopausal status, family history of breast cancer, side of tumor. In univariate analysis the age of menarche, duration of symptoms, tumor size, site in outer quadrant, S phase and skin and nipple involvement all predicted axillary nodal involvement. The length of breast-feeding, increased intraductal component and increased PCNA were inversely proportional to nodal involvement. In multiple regression analysis however only size of the tumor, involvement of the skin and nipple and disease in the outer quadrant of breast were the factors, which assumed significance.

Lack of benefit of granulocyte macrophage or granulocyte colony stimulating factor in patients with febrile neutropenia

OBJECTIVES

To compare the clinical benefits of granulocyte-colony stimulating factor (G-CSF) or granulocyte macrophage-colony stimulating factor (GM-CSF) plus standard supportive care to supportive care alone among cancer patients with febrile neutropenia.

METHODS

Clinical data were collected retrospectively from 148 consecutive cancer patients with neutropenia and fever. Patients had hematologic (i.e., acute leukemias or lymphoproliferative disorders) or non-hematologic malignancies (i.e., solid tumors including carcinoma of breast, lung, or colon). Clinical variables analyzed included: age and sex; underlying malignancies; chemotherapy regimens; symptoms at time of presentation; duration of fever prior to study enrollment; days from chemotherapy until administration of GM-CSF or G-CSF; number of previous neutropenic episodes; duration of fever and day of defervescence; absolute neutrophil count on day of defervescence; duration of neutropenia; number and types of antibiotics used; day amphotericin B begun; number of culture-documented infective episodes involving bloodstream, lung, pleura, urinary tract, gastrointestinal tract, intravenous cannulae, or skin; types of antimicrobial isolates; cost of cytokine therapy; length of hospital stay and clinical outcome.

RESULTS

The use of myeloid growth factors increased the number of circulating peripheral white blood cells, but no significant effect was noted in terms of duration of neutropenia or fever, number of culture-proven infections (except pneumonia; p < 0.04), length of hospital stay, or survival.

CONCLUSION

In areas with limited health care resources, expensive treatment with GM-CSF or G-CSF should be reserved for patients with complicated febrile neutropenia where the expected risk of infection is high and the duration of neutropenia is prolonged, or those with documented infections that are refractory to antibiotic treatment.

Radiological features of hepatocellular carcinoma in Southern Pakistan

We describe the radiological features of 201 patients diagnosed as having hepatocellular carcinoma (HCC) in Southern Pakistan. The cases of biopsy-proven HCC were analysed retrospectively for years 1994-1998. Age, sex, underlying cirrhosis, hepatitis markers, and radiological description were recorded. The mean age was 56 years. There were 149 males and 52 females. 82% patients had underlying cirrhosis. The tumour size was measured in at least two dimensions, and the maximum mean tumour size at the time of diagnosis was 8.3 +/- 4.0 cm. Of the tumours 79.5% were more than 5 cm; 56% of primary HCC were multifocal; 51% involved the right lobe only; 15% involved the left lobe; 34% involved both lobes of liver. Portal vein thrombosis was detectable in 17%. There were no significant differences in the radiological patterns amongst patients who had hepatitis B virus related and hepatitis C virus-related HCC except for age.

Probing molecular conformations with electron momentum spectroscopy: the case of n-butane

High-resolution (e,2e) measurements of the valence electronic structure and momentum-space electron density distributions of n-butane have been exhaustively reanalyzed in order to cope with the presence of two stable structures in the gas phase, namely the all-staggered and gauche conformers. The measurements are compared to a series of Boltzmann-weighted simulations based on the momentum-space form of Kohn-Sham (B3LYP) orbital densities, and to ionization spectra obtained from high-level [ADC(3)] one-particle Green's Function calculations. Indubitable improvements in the quality of the simulated (e,2e) ionization spectra and electron momentum profiles are seen when the contributions of the gauche form of n-butane are included. Both the one-electron binding energies and momentum distributions consistently image the distortions and topological changes that molecular orbitals undergo due to torsion of the carbon backbone, and thereby exhibit variations which can be traced experimentally. With regard to the intimate relation of (e,2e) cross sections with orbital densities, electron momentum spectroscopy can therefore be viewed as a very powerful, but up to now largely unexploited, conformational probe. The study also emphasizes the influence of thermal agitation in photoionization experiments of all kind.

Clonal deletion and clonal anergy in allogeneic bone marrow chimeras prepared with TBI or TLI

The evolution of Vbeta6-expressing C3H (H2k, Thy 1.2, Mls a-) lymphocytes was investigated in C3H recipients mice pretreated with total body irradiation (TBI) or total lymphoid irradiation (TLI) and infusion of AKR (H2k, Thy 1.1, Mls a+) cells. After TBI (9.5 Gy) all Vbeta6+ Thy 1.2 (C3H) cells, which are capable of reacting against the Mls a antigen that like expressed by AKR mice, were deleted in the thymus and the periphery in stable bone marrow (BM) chimeras obtained by infusion of 5 x 10(6) T-cell-depleted (TCD) AKR BM cells. When, in the opposite combination, 30 x 10(6) C3H spleen cells were infused into TBI-treated AKR cells, all animals developed graft-versus-host disease (GVHD) with no clonal deletion and in contrast, showed an increase in Vbeta6+ C3H cells. After injection of 30 x 10(6) AKR BM cells into TLI-treated C3H mice no C3H cells were detected in the thymus and only a small percentage in the periphery. Within these C3H cells Vbeta6+ cells were only partially deleted and anergized as they did not respond in vitro after stimulation with Mls a+ AKR cells or anti-Vbeta6 mAb. Cells suppressing anti-Mls a-reacting C3H cells were not found. After injection of 15 x 10(6) AKR cells more C3H cells were found in the thymus, but only a minority of Vbeta6+ cells persisted in the periphery of these animals. In conclusion in TBI-prepared chimeras only clonal deletion occurred, whereas in TLI-prepared chimeras both clonal deletion and anergy occurred in maintaining tolerance.

Lack of correlation between alpha-fetoprotein and tumor size in hepatocellular carcinoma

OBJECTIVE

To determine whether there was a correlation between tumor size and alpha feto-protein (alpha-FP) levels in hepatocellular carcinoma.

SETTING

Retrospective study in tertiary referral center with specialist Oncology services in Southern Pakistan.

SUBJECTS

Consecutive patients with biopsy-proven hepatocellular carcinoma diagnosed between January 1994 and June 1998.

MAIN OUTCOME MEASURES

Correlation between alpha-FP levels and maximum tumor diameter.

RESULTS

The mean tumor size was 8.3 +/- 4.2 cm. The mean alpha-FP level was 17,027 ng/ml. Twenty four percent patients had an alpha-FP level which was within the normal limits (< 10 ng/ml). There was no correlation between tumor size and alpha-FP levels (r = -0.155; p = 0.129).

CONCLUSION

There was no correlation between the tumor size and alpha-FP levels.

A survival analysis of metastatic breast cancer in Pakistani patients

OBJECTIVE

To determine the overall survival of metastatic breast cancer in the Pakistani patients and compare it with published information.

METHOD

The design was a retrospective analysis of metastatic breast cancer patients from breast cancer database. A total of 137 patient based information was available for review and analysis.

RESULTS

An overall median survival of 2.83 years was noted in metastatic breast cancer patients.

CONCLUSION

This survival figure in this study compares favorably to those published in the literature.

Clinical and molecular studies in a unique family with autosomal dominant limb-girdle muscular dystrophy and Paget disease of bone

PURPOSE

To characterize the clinical features and perform linkage analysis of candidate loci in a large Illinois family with autosomal dominant limb-girdle muscular dystrophy (LGMD) and Paget disease of bone (PDB).

METHODS

The family includes 11 affected individuals (8 M, 3 F). Clinical, biochemical and radiologic evaluations were performed to delineate clinical features of the disorder. Linkage analysis with polymorphic markers was performed for previously identified LGMD, PDB and cardiomyopathy loci.

RESULTS

Onset of PDB is early, at a mean age of 35 y, with classic distribution involving the spine, pelvis, and skull. Muscle weakness and atrophy is progressive with mildly elevated to normal creatine phosphokinase levels. Muscle biopsy in the oldest male revealed vacuolated fibers, however, in others revealed nonspecific myopathy. Affected individuals die from progressive muscle weakness, and respiratory and cardiac failure in their 40s-60s. Linkage analysis excluded autosomal dominant and recessive LGMD, PDB, and cardiomyopathy loci.

CONCLUSION

Autosomal dominant LGMD associated with PDB is an unusual disorder. Linkage analysis indicates a unique locus in this family.

Therapy-related myelodysplasia and secondary acute myelogenous leukemia after high-dose therapy with autologous hematopoietic progenitor-cell support for lymphoid malignancies

PURPOSE

To evaluate the incidence of and risk factors for therapy-related myelodysplasia (tMDS) and secondary acute myelogenous leukemia (sAML), after high-dose therapy (HDT) with autologous bone marrow or peripheral-blood progenitor-cell support, in patients with non-Hodgkin's lymphoma (NHL).

PATIENTS AND METHODS

Between January 1985 and November 1996, 230 patients underwent HDT comprising cyclophosphamide therapy and total-body irradiation, with autologous hematopoietic progenitor-cell support, as consolidation of remission. With a median follow-up of 6 years, 27 (12%) developed tMDS or sAML.

RESULTS

Median time to development of tMDS or sAML was 4.4 years (range, 11 months to 8.8 years) after HDT. Karyotyping (performed in 24 cases) at diagnosis of tMDS or sAML revealed complex karyotypes in 18 patients. Seventeen patients had monosomy 5/5q-, 15 had -7/7q-, seven had -18/18q-, seven had -13/13q-, and four had -20/20q-. Twenty-one patients died from complications of tMDS or sAML or treatment for tMDS or sAML, at a median of 10 months (range, 0 to 26 months). Sixteen died without evidence of recurrent lymphoma. Six patients were alive at a median follow-up of 6 months (range, 2 to 22 months) after diagnosis of tMDS or sAML. On multivariate analysis, prior fludarabine therapy (P =.009) and older age (P =.02) were associated with the development of tMDS or sAML. Increased interval from diagnosis to HDT and bone marrow involvement at diagnosis were of borderline significance (P =.05 and.07, respectively).

CONCLUSION

tMDS and sAML are serious complications of HDT for NHL and are associated with very poor prognosis. Alternative strategies for reducing their incidence and for treatment are needed.

High-dose therapy with autologous bone marrow support as consolidation of remission in follicular lymphoma: long-term clinical and molecular follow-up

PURPOSE

To evaluate the long-term results of high-dose therapy (HDT) in follicular lymphoma, with specific emphasis on the prognostic significance of polymerase chain reaction (PCR)-detectable Bcl-2/IgH rearrangements.

PATIENTS AND METHODS

Between June 1985 and October 1995, 99 patients with follicular lymphoma received HDT as consolidation of second or subsequent remission. Bone marrow was treated in vitro with anti-B-cell antibodies and complement.

RESULTS

Sixty-five patients remained alive, 49 treatment-failure free, with a median follow-up of 5.5 years (range, 1.5 to 12.5 years). Four "early" and 10 "late" deaths occurred from treatment-related causes; seven of the latter were due to secondary myelodysplasia (s-MDS) or secondary acute myeloblastic leukemia. Overall, 12 (12%) of the 99 patients developed s-MDS or acute myeloblastic leukemia. Kaplan-Meier estimates of freedom from recurrence (FFR) and survival rates at 5 years were 63% (95% confidence interval [CI], 52% to 72%) and 69% (95% CI, 58% to 78%), respectively. For all 99 patients, in multivariate analysis, absence of the Bcl-2/IgH rearrangement at the time of diagnosis (hazards ratio [HR], 0.39; P =.04) and three or fewer treatment episodes before HDT (HR, 0.03; P =.001) were significant prognostic factors for improved survival. For patients bearing Bcl-2/IgH rearrangements, in univariate and multivariate analyses, absence of a PCR-detectable Bcl-2/IgH rearrangement during follow-up was associated with a significantly lower risk of recurrence (adjusted HR, 0.13; P <.001) and death (HR, 0.25; P =.02), whereas the PCR status of the reinfused bone marrow did not correlate with outcome.

CONCLUSION

Prolonged FFR can be achieved in patients with follicular lymphoma after HDT, but as yet there is no survival advantage compared with conventional treatment. These results confirm that elimination of cells bearing the Bcl-2/IgH rearrangement is highly desirable and should be attempted. The incidence of s-MDS is of increasing concern in this setting.

The clinical pattern of HER-2/neu oncogene overexpressing breast cancer in Pakistani patients at initial presentation: an analysis of HER-2/neu positive versus negative disease--a preliminary report

BACKGROUND

HER 2/new oncogene is an important prognostic marker in Breast Cancer and has implications in therapy planning.

OBJECTIVE

To describe the clinical features of HER 2/new positive and negative Breast Cancer in the Pakistani patient population and note clinical differences between the two groups if any.

DESIGN

A retrospective analysis of Breast Cancer cases at the Aga Khan University, Hospital.

METHOD

Immunochemical staining on formation fixed paraffin embedded tissue using oxidase antiperoxidase method. A total of 152 Breast cancer tissue samples were tested for HER-2/neu gene presence. Of these 43 (39%) samples tested positive and 109 (61%) tested negative. A comparison of the two groups revealed that only a few factors tested for either significance or borderline statistical significance between the two groups. These factors included the estrogen receptor status and the number of lymph nodes involved in the axilla. The progesterone receptor status was of borderline significance.

CONCLUSION

Given the large number of factors tested it appears that there is no consistent defining feature which helps to separate HER-2/neu positive versus HER-2/neu negative cases with Breast Cancer.

Marked mitigation of transplant vascular sclerosis in FasLgld (CD95L) mutant recipients. The role of alloantibodies in the development of chronic rejection

BACKGROUND

In the acute rejection of allografts, the interaction between Fas (CD95) and its ligand (FasL; CD95L) has been shown to be involved in mediating apoptotic cell death. The role, however, of these molecules in the pathogenesis of transplant vascular sclerosis is as yet undetermined. The present study was therefore designed to address this issue.

MATERIAL

C3H/HEJ FasLgld (FasL-; H2k) spontaneously mutant mice were used either as donors or recipients of aortic allografts; wild-type C57B1/6 (B6; H2b) were used as corresponding recipients or donors (n=6/group), respectively. Controls included aortas transplanted across appropriate allogeneic and syngeneic strain combinations. For histopathological evaluations, the grafts were harvested at day 40 after transplantation, at which time, splenocytes and sera were also obtained for mixed leukocyte reaction and complement-mediated microcytotoxicity assays, respectively.

RESULTS

Similar to aortas obtained from allogeneic controls, allografts harvested from FasL- -->B6 recipients had morphological evidence of chronic rejection characterized by circumferential intimal thickening with partial disruption of the elastic membranes. Correspondingly, heightened antidonor cellular reactivity was also witnessed in these recipients. On the contrary, B6 allografts harvested from the majority of C3H-->FasL- recipients exhibited marked preservation of aortic morphology. Although these recipients had diminished antidonor cellular proliferation, the titers of alloantibodies were markedly elevated.

CONCLUSION

The presence of FasL-expressing functional cytotoxic T cells is required for the pathogenesis of transplant vascular sclerosis. The significant reduction and/or absence of chronic rejection with the concomitant retention of antidonor humoral response in C3H FasL- recipients of B6 aortas prompt us to suggest that perhaps posttransplantation vasculopathy is initiated by cell-mediated cytotoxicity with its perpetuation facilitated by alloantibodies.

Use of the polymerase chain reaction and direct sequencing analysis to detect cells with the t(14;18) in autologous bone marrow from patients with follicular lymphoma, before and after in vitro treatment

Between August 1993 and February 1994, 25 patients with follicular or transformed follicular lymphoma had bone marrow harvested at St Bartholomew's Hospital (SBH) with a view to proceeding to high-dose treatment comprising: cyclophosphamide 60 mg/kg x 2 and total body irradiation, 200 cGy x 6, supported by autologous bone marrow transplantation (ABMT). The marrow mononuclear cell fraction was treated in vitro with four anti-B cell antibodies and baby rabbit complement. The aim of this study was to determine whether in vitro treatment of the marrow could remove morphologically undetectable lymphoma cells. PCR analysis for the t(14;18) was used to determine the presence or absence of lymphoma. At the time of the bone marrow harvest, 21/25 bone marrow samples were positive for the t(14;18), in 15/22 patients, the rearrangement could also be demonstrated in peripheral blood. After in vitro treatment, 18/21 samples (86%) remained 'PCR positive'. Sequence analysis of the t(14;18) PCR products was performed on the latter and on lymph node biopsy material taken at diagnosis from 12 patients. The same t(14;18) sequences were found in the bone marrow harvest samples as in the patients' original biopsies. These results suggest that this form of in vitro treatment does not completely eradicate the t(14;18) bearing clone. New and better methods need to be developed.

Presence of intrinsic B lymphocyte tolerance in mixed but not in complete semiallogeneic bone marrow chimeras

The existence of intrinsic B lymphocyte transplantation tolerance was investigated in murine semiallogeneic complete and mixed bone marrow chimeras. Complete chimeras (CC), which were obtained by infusing 20x10(6) C57BL/10 (P1) bone marrow (BM) cells into irradiated (10.5 Gy) (C57BL/10xBALB/c) F1 recipients, were repopulated for 100% with P1 lymphohematopoietic cells. In mixed chimeras (MC), which were obtained by injection of 15 x 10(6) P1 together with 5 x 10(6) F1 BM cells, between 15% and 40% of F1 lymphohematopoietic cells persisted after BM transplantation. Neither MC nor CC were able to develop significant T cell immunity (mixed lymphocyte reaction) or B cell immunity (IgG alloantibodies) against the mismatched host antigens (BALB/c), despite repetitive immunizations. However, after immunization with third-party cells (C3H), the IgG alloantibodies raised cross-reacted with the host-type (BALB/c) antigens in the CC but not in the MC. This suggested that intrinsic B lymphocyte tolerance for host antigens had occurred in MC but not in CC. This was further evidenced in transfer experiments using lethally irradiated C57BL/10 mice reconstituted with purified control C57BL/10 T lymphocytes together with purified C57BL/10 B lymphocytes isolated from CC or MC. Only the recipients reconstituted with B lymphocytes from CC, and not those from MC, produced anti-BALB/c IgG alloantibodies after immunization. These results show that intrinsic B lymphocyte tolerance can be achieved after transplantation and that this depends on the presence of lymphohemopoietic cells expressing the tolerogens.