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In an effort to prevent potentially fatal adverse reactions to carbamazepine, the US Food and Drug Administration (FDA) issued an alert in 2007 containing pharmacogenomic information, which is still in effect today. The alert states that carbamazepine-induced skin reactions are significantly more common in patients with the human leukocyte antigen (HLA)-B*1502 allele and that these people are almost exclusively from 'broad areas of Asia, including South Asian Indians.' This study reviews the medical evidence relied upon by the FDA and finds that the alert does not accurately reflect the medical evidence relied upon in 2007 or evidence that has been generated over the last 5 years since the label was created. The FDA drug labeling should be modified to reflect current medical evidence.

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Sputum obtained from healthy subjects and patients with known lung tumours has been challenged with fluorescent probes for the presence of an active cell surface protease. The mature epithelial cells from healthy patients' sputum lacked ability to bind these fluorescent probes whilst the majority of mature epithelial cells in the tumour patients' sputum bound these probes and consequently fluoresced. This demonstrable difference in the cell surface chemistry of mature epithelial cells was linked to the presence of lung tumour cells, which also possessed this cell surface protease. The mechanism of this induced cell surface enzyme appearance is not understood.

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Cells were collected on glass slides by touching tumour surfaces (A) and normal regions (B) of the lung. The slides were stained with a nuclear stain and a fluorescent probe for a tumour associated cell surface protein. The (B) slides from the normal regions lacked fluorescent epithelial cells. The tumour slides (A) contained typical tumour cells and dyskaryotic cells which exhibited cell surface fluorescence.

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Cells were collected from sites of known lung tumours and corresponding control areas of these lungs. Fluorescent staining demonstrated that the tumour cells and epithelial cells (cytologically these cells appeared normal) both possessed a receptor for these fluorescent probes. Fluorescent labelling of sputum cells from these tumour patients also resulted in fluorescent labelling of these "cyto logically normal" epithelial cells. No such fluorescent epithelial cells were observed in sputum samples collected from control subjects or in cells collected from the control areas of the tumour patients' lungs. We conclude that a cell surface protein receptor is expressed in lung tumour-associated epithelial cells but is absent from control sputum epithelial cells.

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OBJECTIVE: To investigate the hypothesis that image cytometry of sputum specimens can detect squamous carcinoma without requiring visually abnormal cells. DESIGN: The sensitivity and specificity of image cytometry were evaluated in a case-control study. MATERIAL AND METHODS: Seventy-three sputum slides from the Mayo portion of the National Cancer Institute Cooperative Early Lung Cancer Study were restained by a modified Feulgen method. We examined 40 slides from 9 patients in whom squamous carcinoma developed and 33 slides from 11 patients in whom no cancer developed during a follow-up of at least 5 years. Images of normal epithelial nuclei were collected by using an automated image cytometer. Discriminant analysis was used to determine differences in DNA distribution of normal nuclei in sputum specimens from noncancer patients versus normal nuclei in sputum samples from patients in whom carcinoma developed. RESULTS: By using features based on DNA distribution, 74% correct classification of nuclei was possible without human review of the material and without the use of visually abnormal nuclei. A receiver operating characteristic curve demonstrated sensitivities and specificities, including 40% sensitivity and 90% specificity. CONCLUSION: Although this study was limited to 20-year-old slides and squamous cell carcinoma, automated image cytometry detected a substantial proportion of patients with squamous cell cancer without using visually abnormal nuclei.

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A total of 152 normal bronchial biopsy sections--63 from normal subjects, 42 from patients with dysplasia, 28 from patients with early or advanced lung cancer with squamous and nonsquamous histopathology, and 19 from resected lung cancer patients--were examined for the presence of malignancy-associated changes (MACs). A standard, white light bronchoscope examination and a multispectral fluorescence bronchoscope examination were performed on every subject to determine the status of the bronchial epithelial tissue. Any suspect areas were biopsied to determine the status of the area and to establish the highest grade of abnormality in the patient. In addition, for every subject, a bronchoscopically normal area of the bronchus in the opposite lung or another lobe was biopsied. The specimens were confirmed to be normal by conventional histopathologic criteria using hematoxylin and eosin stain. Sections of biopsies were stained using a DNA stoichiometric stain, and approximately 250 images of visually normal epithelial cell nuclei from each of the biopsies were collected, as were approximately 40 images of leukocyte cell nuclei. For each of these images > 60 nuclear features were calculated that quantified the size, shape and DNA volume of the nuclei as well as DNA spatial organization in the nuclei. The features were then used to train an automated classifier to recognize normal epithelial cell nuclei from normal subjects and normal-appearing epithelial cell nuclei (MAC cell nuclei) from lung cancer patients.(ABSTRACT TRUNCATED AT 250 WORDS)

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Touch preparations from 60 cases of T1 adenocarcinoma were analyzed using a high-resolution, automated image cytometer. These cases were divided according to pathologic stage: stage I, 31; stage II, 3; stage III, 19; and stage IV, 7. For each nucleus 57 features were analyzed, and using a linear combination of three texture features describing the DNA distribution in the cell nucleus (TARL, ODMAX and FAREA1), aggressive cancer cells belonging to stage III/IV could be identified. The best discrimination between the stages was achieved when the frequency of aggressive cancer cells was 48%; the correct classification rate was 77%. Using this criterion, 22 of 27 patients (81%) who died of cancer within five years after surgery were correctly predicted. These results suggest that high-resolution cytometry may be of value in predicting the biologic behavior of adenocarcinoma cases, especially in stage I/II.

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Specific gene hypermethylation has been shown in DNA from neonatal rats exposed to the phytoestrogens, coumestrol, and equol. The pancreas is an organ in which estrogen receptors have been shown to be present. Studies have correlated the development of acute pancreatitis with rising levels of human estrogen binding proteins. Neonatal rats were dosed with 10 or 100 micrograms of coumestrol or equol on postnatal day (PND) 1-10. The animals were sacrificed at Day 15. The pancreas was excised and pancreatic acinar cells isolated for molecular analysis. DNA was isolated from the cells by lysis in TEN-9 buffer supplemented with proteinase K and 0.1% SDS. High molecular weight (HMW) DNA was digested with the methylated DNA specific restriction enzymes, Hpa II and Msp I, for determination of methylation profiles. Both coumestrol and equol at high doses caused hypermethylation of the c-H-ras proto-oncogene. No hypermethylation or hypomethylation was observed in the proto-oncogenes, c-myc or c-fos. Methylation is thought to be an epigenetic mechanism involved in the activation (hypomethylation) or inactivation (hypermethylation) of cellular genes which are known to play a role in carcinogenesis. Epidemiology studies have shown that equol may have anti-carcinogenic effects on some hormone-dependent cancers. Additional studies are needed to further understand the role of phytoestrogens and methylation in relation to pancreatic disorders.

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A fluorescent probe (rhodamine a-N-agmatine) has been used to locate cells possessing a surface protease in sputum smears. Malignant epithelial cells possess this protease and can be quickly located by this technique. These results have been confirmed by using a second fluorescent probe (9-animo acridine) for this same cell surface protease.

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Mik beta 1 is a mouse mAb directed at the beta-subunit of the human IL-2R (Tac) that inhibits IL-2 binding and inhibits IL-2 induction of large granular lymphocytes (LGL). Mik beta 1 alone does not inhibit IL-2-induced T-cell proliferation, but acts synergistically with anti-Tac to inhibit IL-2-induced proliferation of activated T cells. To evaluate these effects for possible therapy in humans, we constructed two humanized Mik beta 1 antibodies by combining the complementarity-determining regions of the murine antibody with human framework and constant regions. Compared with murine Mik beta 1, the two humanized Mik beta 1 antibodies, which differ in their degree of humanization, had similar affinities for IL-2R beta. The murine Mik beta 1 and one of the humanized Mik beta 1 antibodies were equivalent in competing for IL-2 binding to IL-2R beta and inhibiting IL-2 induction of LGL cytotoxicity. The activity of the second humanized antibody was significantly reduced. The three Mik beta 1 antibodies act synergistically to varying degrees with humanized anti-Tac to prevent IL-2-induced proliferation of activated T cells. This capacity to synergize paralleled their abilities to inhibit IL-2 binding. In addition, both humanized antibodies directed antibody-dependent cell-mediated cytotoxicity. We hope that humanized Mik beta 1 in combination with humanized anti-Tac will provide a new immunosuppressive therapy for the treatment of autoimmune diseases, graft-versus-host disease, and prevention of allograft rejection.

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Protein C alpha coordinates are used to accurately reconstruct complete protein backbones and side-chain directions. This work employs potentials of mean force to align semirigid peptide groups around the axes that connect successive C alpha atoms. The algorithm works well for all residue types and secondary structure classes and is stable for imprecise C alpha coordinates. Tests on known protein structures show that root mean square errors in predicted main-chain and C beta coordinates are usually less than 0.3 A. These results are significantly more accurate than can be obtained from competing approaches, such as modeling of backbone conformations from structurally homologous fragments.

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Mature epithelial cells derived from the sputum of normal healthy adults lack GB, while the epithelial cells of sputum collected from patients with lung tumours contain a spectrum of epithelial cells with active GB, some of which are clearly tumour cells, based upon their morphology. The presence of abnormal epithelial cells was confirmed by the cytologist whilst observing the fluorescent stained cells and later by independent cytological analysis of these same cells employing conventional stains.

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The genetically engineered "humanized" anti-Tac antibody (HAT) has been shown to bind the p55 chain of the human IL-2R with an affinity close to that of the murine anti-Tac. Although the HAT molecule contains all six mouse CDR, it was not known which, and to what extent, each of the CDR contributes to Ag binding. These questions were addressed by constructing a series of variant HAT antibodies, each substituting a single HAT CDR with a heterologous CDR. The association constants of the variant HAT antibodies to p55 were determined by competitive binding analysis. We find that CDR 1 and 3 of the H chain and CDR 3 of the L chain are essential for maintaining binding. The remaining three CDR appear to be involved to a lesser degree.

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The anti-Tac monoclonal antibody is known to bind to the p55 chain of the human interleukin 2 receptor and to inhibit proliferation of T cells by blocking interleukin 2 binding. However, use of anti-Tac as an immunosuppressant drug would be impaired by the human immune response against this murine antibody. We have therefore constructed a "humanized" antibody by combining the complementarity-determining regions (CDRs) of the anti-Tac antibody with human framework and constant regions. The human framework regions were chosen to maximize homology with the anti-Tac antibody sequence. In addition, a computer model of murine anti-Tac was used to identify several amino acids which, while outside the CDRs, are likely to interact with the CDRs or antigen. These mouse amino acids were also retained in the humanized antibody. The humanized anti-Tac antibody has an affinity for p55 of 3 x 10(9) M-1, about 1/3 that of murine anti-Tac.

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Euler equations characteristic of the electronic reduced density matrix have previously been obtained by minimizing an energy functional subject to trace constraints P(K) = N, in which N is the number of particles. It is shown that these constraints are inadequate to exclude variations that violate N-representability conditions. However, a first-order reduced density matrix that does satisfy N-representability conditions is formulated as a functional of the orbital densities through use of angular momentum recoupling. Modified variational constraints are proposed.

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A method is presented for variational calculation of the energy and the spin densities derived from a single-determinant wavefunction. Sum and difference coordinates [unk]R = (1/2)([unk]r(1) + [unk]r(1)) and [unk]r = [unk]r(1) - [unk]r(1) are introduced, and the density matrix P([unk]r(1),[unk]r(1)) is expanded in partial waves in the new coordinate frame: [Formula: see text] The functions h(L)(epsilon,r) are bound or continuum hydrogenic functions with energy epsilon.It is shown that the spin densities depend on the s partial waves only, and a Euler equation for these partial waves is derived: [Formula: see text] in which U([unk]R) is the electrostatic potential, a(epsilon) = h(0)(epsilon,0), and mu is chosen to normalize the spin density to N electrons. Further, the electronic energy can be expressed in terms of the s partial waves and the constant mu in the above equations.The idempotent density matrix that ensues from a particular choice of functions {B(00)[unk](epsilon,[unk]R)} is generated by choosing partial density waves {B(LM)(epsilon,[unk]R), L > 0} so that tr[P(2)(1 - P)(2)] is minimized.