Solvent control of intramolecular proton transfer: is 4-hydroxy-3-(piperidin-1-ylmethyl)-1-naphthaldehyde a proton crane?

The solvent dependent excited state dynamics of 4-hydroxy-3-(piperidin-1-ylmethyl)-1-naphthaldehyde (compound 2), a candidate for a molecular switch based on intramolecular proton transfer, was investigated by ultrafast spectroscopy and quantum-chemical calculations. In acetonitrile a mixture of molecules in the enol and zwitterionic proton transfer (PT) form exists in the ground state. However, the zwitterion is the energetically favored one in the electronically excited state. Optical excitation of the enol form results in intramolecular proton transfer and formation of the PT form within 1.4 ps. In addition we observe the appearance of a long living species with a rate of 1/(330 ps) which returns to the original ground state on time scales beyond 2 ns and which is attributed to the triplet state. In toluene the enol form is the only observed ground state tautomer, but no light induced proton transfer occurs. Again the long living triplet state is formed, even with a faster rate of 1/(11 ps). In methanol hydrogen bonds between 2 and solvent molecules stabilize strongly the PT form in the ground as well as in the excited state. Also in this case no light induced intramolecular proton transfer was observed but the formation of a long living species was. However, its absorption spectrum is distinctly different from the triplet state seen in acetonitrile and methanol.

4-Hydroxy-1-naphthaldehydes: proton transfer or deprotonation

Proton captured/proton lost: in 4-hydroxy-1-naphthaldehyde concentration dependent deprotonation is observed, while when a piperidine unit is attached the proton is captured.

The effect of the water on the curcumin tautomerism: a quantitative approach

The tautomerism of curcumin has been investigated in ethanol/water binary mixtures by using UV-Vis spectroscopy and advanced quantum-chemical calculations. The spectral changes were processed by using advanced chemometric procedure, based on resolution of overlapping bands technique. As a result, molar fractions of the tautomers and their individual spectra have been estimated. It has been shown that in ethanol the enol-keto tautomer only is presented. The addition of water leads to appearance of a new spectral band, which was assigned to the diketo tautomeric form. The results show that in 90% water/10% ethanol the diketo form is dominating. The observed shift in the equilibrium is explained by the quantum chemical calculations, which show that water molecules stabilize diketo tautomer through formation of stable complexes. To our best knowledge we report for the first time quantitative data for the tautomerism of curcumin and the effect of the water.

A new variant chromosomal translocation t(2;2)(p23;q23) in CD30+/Ki-1+ anaplastic large cell lymphoma

A case with a complex chromosome abnormality with a t(2;2)(p23;q23) in CD30+/Ki-1+ anaplastic large cell lymphoma (ALCL) is described. This chromosome aberration has not been reported previously in neoplastic diseases and was associated with T-cell phenotype and involvement of the nasopharynx by the tumour.

Unusual chromosome aberration, t(13;14)(q32;q32.3), in a case of essential thrombocythemia with extreme thrombocytosis

A case of essential thrombocythemia (ET) with extreme thrombocytosis in a 70-year-old male patient is described. The cytogenetic analysis revealed a pathologic clone with the following previously unreported, unusual karyotype: 46,XY,t(13;14)(q32:q32.3) and pericentric inversion of chromosome 9. The possible association of t(13;14) with the high platelet count is discussed.

Case of acute monocytic leukemia with 47,XY,+X,t(2;10)(q21.1;q26.1) and basophilia

The clinical cytogenetic findings of a patient with acute monocytic leukemia with peripheral and bone marrow basophilia are presented. The cytogenetic analysis of bone marrow cells established a pathologic clone with the following unusual karyotype: 47,XY,+X,t(2;10)(q21.1;q26.1). This chromosome abnormality has not been reported previously in leukemic diseases.

Induction of characteristic chromosomal aberrations, particularly X-trisomy, in cultured human lymphocytes treated by ochratoxin A, a mycotoxin implicated in Balkan endemic nephropathy

Ochratoxin A (OA), a mycotoxin which induces nephropathy and kidney tumours in rats and mice, is a contaminant of food consumed by a population with a high incidence of endemic nephropathy (EN). It was therefore tested in vitro for its ability to induce chromosomal aberrations in human peripheral lymphocytes in a small number of subjects, in the presence or absence of a kidney microsomal metabolic activation system. OA was found to induce aberrations on X chromosomes of similar types to those previously detected in lymphocytes from patients suffering from endemic nephropathy.

Complex translocation t(8;12;14) in a cell line derived from a child with nonendemic Burkitt-type acute lymphoblastic leukemia

A cell line is described with a typical Burkitt lymphoma (BL) marker 14q+ due to the classical reciprocal translocation between chromosome #8 and #14 with breakpoints at 8q24.1 and 14q32.3. In addition, an interstitial piece from the long arm of 12(q24.1-q24.3) is inserted at the site of the exchange on chromosome #8, proximal to 14q32.3.

High resolution chromosome analysis of constitutional and acquired t(15;17) maps c-erbA to subband 17q11.2

High resolution chromosome analysis was performed on bone marrow cells from four patients with acute promyelocytic leukemia and t(15;17), and in lymphocytes from two unrelated, phenotypically normal persons with an apparently identical constitutional translocation. Scrutiny of prophase-prometaphase chromosomes localized the breakpoints in all six cases to subbands 15q22.3 and 17q11.2. Molecular genetic studies have localized the oncogene c-erbA to chromosome #17 between the breakpoints of the constitutional and the acquired anomaly. The present results, therefore, map c-erbA to subband 17q11.2.

Satellite DNA in the three C-bands of an unusual mouse marker chromosome. A model of chromosomal evolution

A marker chromosome in the stemline of a new murine cell line is described on the basis of different stainings and in situ hybridization. The marker was characterized originally by three C-bands, one from each centromeric region of the three chromosomes constituting the marker. In the course of stemline evolution, two of the C-bands have been lost and the marker has developed into a monocentric chromosome, phenotypically and functionally normal.

Alternative involvement of two cytogenetically distinguishable breakpoints on chromosome 8 in Burkitt's lymphoma associated translocations

The chromosomes of 16 Burkitt's lymphoma (BL) derived cell lines were submitted to high-resolution G-band analysis. They included seven lines with t(8;14), three with t(2;8), and four with t(8;22). The translocation breakpoint in chromosome #14 was located in 14q32.3, in chromosome #2 in 2p11.1, and in chromosome #22 in 22q12.12. In chromosome #8, the translocation breakpoint was located in two cytogenetically distinct subbands: 8q24.1 in cell lines with t(8;14) and t(2;8) and 8q24.22 in cell lines with t(8;22). In the light of recent molecular findings, these results indicate that the distance between the c-myc gene, located in 8q24, and the Ig sequences might be much larger in BL lines with t(8;22) than in those with t(2;8).

Chromosome aberrations in peripheral lymphocytes of male homosexuals

Karyotypes of peripheral lymphocytes of 19 male homosexuals showed increased hypodiploidy. Chromosomes #19 and #20 were most frequently lost. Also, structural chromosome aberrations frequently occurred consisting chiefly of translocations and simple chromosome breaks. Terminal deletions, inversions, and isochromosomes occurred less commonly. In three of the cases, 100% of the cells were involved in a pericentric inversion of a chromosome #9. Chromosomes #3 in p21.1 and 1 in p32.3 were repeatedly affected. Structural aberrations were seen less frequently in men with acquired immunodeficiency syndrome(AIDS) and AIDS-related complex than in asymptomatic homosexuals. The hypodiploidy with preferential loss of chromosomes was constantly present. The marker chromosomes and simple breaks at repeated sites are another manifestation of damage to the immune system in these male homosexuals from Greenwich Village in New York City. The chromosomal damage was potentially the result of exposure to amyl and butyl nitrites, viral infections, or immunologic reactions to sperm, which crossreact with lymphocytes.

Small noncleaved B cell Burkitt-like lymphoma with chromosome t(8;14) translocation and Epstein-Barr virus nuclear-associated antigen in a homosexual man with acquired immune deficiency syndrome

This case report describes new manifestations of the acquired immune deficiency syndrome (AIDS) in a promiscuous homosexual man. Investigation of upper gastrointestinal bleeding in the patient lead to discovery of a high-grade, small, noncleaved cell (Burkitt-like) gastroduodenal lymphoma with visceral and extralymphatic extension. Specific phenotyping of the lymphoma revealed that it was a monoclonal B cell lymphoma of mu kappa isotype. An in vitro cell line was established that was Epstein-Barr virus nuclear-associated antigen-positive. The lymphoma cells displayed a t(8;14) translocation similar to endemic African Burkitt lymphoma. Epstein-Barr virus genomes were identified in the lymphoma and an axillary lymph node biopsy specimen by molecular hybridization. These data strongly suggest that Epstein-Barr virus actively infected this patient. However, he showed normal Epstein-Barr virus-specific serologic responses, indicating an immune defect against the virus.

Chromosome #14 markers in two Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines of normal origin differ from the Burkitt lymphoma (BL)-associated 14q+ marker

Two among ten Epstein-Barr Virus (EBV)-transformed lymphoblastoid cell lines contained a 14q+ marker in a low frequency of the cells (2 and 9%). By means of "mesome-prosome" analysis of the G-band patterns of these markers; it was established that the additional chromosome segments of these two 14q+ markers came from chromosomes #3 and #5, respectively, and not from chromosome #8 as in the 14q+ marker of Burkitt lymphoma. Chromosome #8 was not involved at all in any changes in the ten lymphoblastoid cell lines studied.

Reciprocal 8;14 translocation in EBV-negative B-cell acute lymphocytic leukemia with Burkitt-type cells

A cytogenetic study, including prophase-prometaphase chromosome analysis, of a patient with EBV-genome-negative acute lymphocytic leukemia of B-cell type with Burkitt-type cells is presented. All bone-marrow mitoses examined had a 14q+ marker chromosome which was identified as a reciprocal 8;14 translocation of exactly the same type as in Burkitt's lymphoma.