Cyclin-dependent kinases as a therapeutic target for stroke

Cyclin-dependent kinases (CDKs) are commonly known to regulate cell proliferation. However, previous reports suggest that in cultured postmitotic neurons, activation of CDKs is a signal for death rather than cell division. We determined whether CDK activation occurs in mature adult neurons during focal stroke in vivo and whether this signal was required for neuronal death after reperfusion injury. Cdk4/cyclin D1 levels and phosphorylation of its substrate retinoblastoma protein (pRb) increase after stroke. Deregulated levels of E2F1, a transcription factor regulated by pRb, are also observed. Administration of a CDK inhibitor blocks pRb phosphorylation and the increase in E2F1 levels and dramatically reduces neuronal death by 80%. These results indicate that CDKs are an important therapeutic target for the treatment of reperfusion injury after ischemia.

Desoxyepothilone B is curative against human tumor xenografts that are refractory to paclitaxel

The epothilones are naturally occurring, cytotoxic macrolides that function through a paclitaxel (Taxol)-like mechanism. Although structurally dissimilar, both classes of molecules lead to the arrest of cell division and eventual cell death by stabilizing cellular microtubule assemblies. The epothilones differ in their ability to retain activity against multidrug-resistant (MDR) cell lines and tumors where paclitaxel fails. In the current account, we focus on the relationship between epothilone and paclitaxel in the context of tumors with multiple drug resistance. The epothilone analogue Z-12,13-desoxyepothilone B (dEpoB) is >35,000-fold more potent than paclitaxel in inhibiting cell growth in the MDR DC-3F/ADX cell line. Various formulations, routes, and schedules of i.v. administration of dEpoB have been tested in nude mice. Slow infusion with a Cremophor-ethanol vehicle proved to be the most beneficial in increasing efficacy and decreasing toxicity. Although dEpoB performed similarly to paclitaxel in sensitive tumors xenografts (MX-1 human mammary and HT-29 colon tumor), its effects were clearly superior against MDR tumors. When dEpoB was administered to nude mice bearing our MDR human lymphoblastic T cell leukemia (CCRF-CEM/paclitaxel), dEpoB demonstrated a full curative effect. For human mammary adenocarcinoma MCF-7/Adr cells refractory to paclitaxel, dEpoB reduced the established tumors, markedly suppressed tumor growth, and surpassed other commonly used chemotherapy drugs such as adriamycin, vinblastine, and etoposide in beneficial effects.

Targeted mutation of the murine arylhydrocarbon receptor nuclear translocator 2 (Arnt2) gene reveals partial redundancy with Arnt

The ubiquitously expressed basic helix–loop–helix (bHLH)-PAS protein ARNT (arylhydrocarbon receptor nuclear transporter) forms transcriptionally active heterodimers with a variety of other bHLH-PAS proteins, including HIF-1α (hypoxia-inducible factor-1α) and AHR (arylhydrocarbon receptor). These complexes regulate gene expression in response to hypoxia and xenobiotics, respectively, and mutation of the murine Arnt locus results in embryonic death by day 10.5 associated with placental, vascular, and hematopoietic defects. The closely related protein ARNT2 is highly expressed in the central nervous system and kidney and also forms complexes with HIF-1α and AHR. To assess unique roles for ARNT2 in development, and reveal potential functional overlap with ARNT, we generated a targeted null mutation of the murine Arnt2 locus. Arnt2−/− embryos die perinatally and exhibit impaired hypothalamic development, phenotypes previously observed for a targeted mutation in the murine bHLH-PAS gene Sim1 (Single-minded 1), and consistent with the recent proposal that ARNT2 and SIM1 form an essential heterodimer in vivo [Michaud, J. L., DeRossi, C., May, N. R., Holdener, B. C. & Fan, C. (2000) Mech. Dev. 90, 253–261]. In addition, cultured Arnt2−/− neurons display decreased hypoxic induction of HIF-1 target genes, demonstrating formally that ARNT2/HIF-1α complexes regulate oxygen-responsive genes. Finally, a strong genetic interaction between Arnt and Arnt2 mutations was observed, indicating that either gene can fulfill essential functions in a dose-dependent manner before embryonic day 8.5. These results demonstrate that Arnt and Arnt2 have both unique and overlapping essential functions in embryonic development.

Iron chelates bind nitric oxide and decrease mortality in an experimental model of septic shock.

The hydroxamic acid siderophore ferrioxamine B [FeIII(HDFB)+] and the iron complex of diethylenetri-aminepentaacetic acid [FeIII(DTPA)2-] protected mice against death by septic shock induced by Corynebacterium parvum + lipopolysaccharide. Although FeIII(DTPA)2- was somewhat more effective than FeIII(HDFB)+, the iron-free ligand H4DFB+ was significantly more effective than DTPA. The hydroxamic acid chelator has a much higher iron affinity than the amine carboxylate, allowing for more efficient formation of the FeIII(HDFB)+ complex upon administration of the iron-free ligand. Electrochemical studies show that FeIII(DTPA)2- binds NO stoichiometrically upon reduction to iron(II) at biologically relevant potentials to form a stable NO adduct. In contrast, FeIII(HDFB)+ is a stable and efficient electrocatalyst for the reduction of NO to N2O at biologically relevant potentials. These results suggest that the mechanism of protection against death by septic shock involves NO scavenging and that particularly effective drugs that operate a low dosages may be designed based on the principle of redox catalysis. These complexes constitute a new family of drugs that rely on the special ability of transition metals to activate small molecules. In addition, the wealth of information available on siderophore chemistry and biology provides an intellectual platform for further development.

A dominant-negative mutant of human poly(ADP-ribose) polymerase affects cell recovery, apoptosis, and sister chromatid exchange following DNA damage.

Poly(ADP-ribose) polymerase [PARP; NAD+ ADP-ribosyltransferase; NAD+:poly(adenosine-diphosphate-D-ribosyl)-acceptor ADP-D-ribosyltransferase, EC 2.4.2.30] is a zinc-dependent eukaryotic DNA-binding protein that specifically recognizes DNA strand breaks produced by various genotoxic agents. To study the biological function of this enzyme, we have established stable HeLa cell lines that constitutively produce the 46-kDa DNA-binding domain of human PARP (PARP-DBD), leading to the trans-dominant inhibition of resident PARP activity. As a control, a cell line was constructed, producing a point-mutated version of the DBD, which has no affinity for DNA in vitro. Expression of the PARP-DBD had only a slight effect on undamaged cells but had drastic consequences for cells treated with genotoxic agents. Exposure of cell lines expressing the wild-type (wt) or the mutated PARP-DBD, with low doses of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) resulted in an increase in their doubling time, a G2 + M accumulation, and a marked reduction in cell survival. However, UVC irradiation had no preferential effect on the cell growth or viability of cell lines expressing the PARP-DBD. These PARP-DBD-expressing cells treated with MNNG presented the characteristic nucleosomal DNA ladder, one of the hallmarks of cell death by apoptosis. Moreover, these cells exhibited chromosomal instability as demonstrated by higher frequencies of both spontaneous and MNNG-induced sister chromatid exchanges. Surprisingly, the line producing the mutated DBD had the same behavior as those producing the wt DBD, indicating that the mechanism of action of the dominant-negative mutant involves more than its DNA-binding function. Altogether, these results strongly suggest that PARP is an element of the G2 checkpoint in mammalian cells.

Münşeât-ı Nâbî Efendi : manuscript, 1762

Collection of Nâbî's letters, petitions, and other correspondence to various dignitaries. It was compiled after Nâbî's death by Abdürrahim Çelebi by order of Şehid Ali Paşa.

Suicídio : uma análise epidemiológica : estudo retrospetivo da casuística da Delegação do Sul do Instituto Nacional de Medicina Legal e Ciências Forenses, I.P. (2007-2012)

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014

Bologna Process Bucharest Ministerial Conference Takes Place amid Political Crisis in Romania. EUMA Papers Series Vol. 12, No. 5, May 2012

During the last week in April the Ministers responsible for higher education from 47 countries convened in Bucharest, Romania for the Ministerial Conference of the Bologna Process. On April 26 and 27, 2012 the venue for the meeting was the Palace of the Parliament, which was constructed by the dictator Nicolae Ceauşescu in 1984 and completed the year before his death by execution on Christmas Day 1989. One of the largest civilian buildings in the world was location for the first ministerial conference to take place since the European Higher Education Area (EHEA) became effective in 2010. Originally the creation of the EHEA was envisaged by the Bologna Process Declaration in 1999 which had representatives from 29 countries as signatories. This essay will describe the proceedings of the Ministerial Conference, report on the negotiations among delegates in parallel sessions and plenary sessions, discuss the thematic sessions with emphasis on “Global academic mobility: Incentives and barriers, balances and imbalances” and review the adoption of the Bucharest Communiqué and the Bologna Policy Forum Statement.

Factors influencing the experience of the terminal phase and the grieving process: the primary caregiver’s perspective

Theoretical framework: The experience of the terminal phase and death by patients and caregivers is influenced by multiple factors. This study aimed at understanding this experience from the primary caregiver’s perspective. Objectives: To describe the factors that, from the primary caregiver’s perspective, influenced the experience of disease in the terminal phase and mourning for the death of a close person; To understand the influence of nurses’ conduct on the experience of disease in the terminal phase and mourning for the death of a close person from the primary caregiver’s perspective. Methodology: Qualitative descriptive exploratory study. Results: The following factors were valued: To Assume the Caregiver’s Role, To allow for the end-of-life/terminal phase to take place at home/near the family and Process of Care. Regarding the nurses’ conduct, the knowledge, communication and relationship established by nurses were also valued. Conclusion: In addition to expanding the implementation of specific palliative care teams, the acquisition and development of basic skills in this area by most health care professionals is essential.

Sefer ʻEn Yaʻakov.

The last four sedarim of the work were edited after Ibn Habib's death by his son Levi.

The lives of the Lord Chancellors and Keepers of the Great Seal of England.

Vol. 8, edited after the author's death, by Mary Scarlett Campbell, 1869.

Chrestomathie égyptienne, ou Choix de textes égyptiens transcrits, traduits et accompagnés d'un commentaire perpétuel, et précédés d'un abrégé grammatical,

Vols. 3-4 edited after the author's death by his son Vte Jacques de Rougé.

Denkwürdiger und nützlicher rheinischer antiquarius, welcher die wichtigsten und angenehmsten geographischen, historischen und politischen merkwürdigkeiten des ganzen Rheinstroms, von seinem ausflusse in das meer bis zu seinem ursprunge darstellt ; von einem nachforscher in historischen dingen.

The work, which comprised the Mittelrhein only, was continued after the author's death by A.J. Weidenbach, the author of Das Nahethal, II. abth., bd. 16-20 (1869-1871)

English writers: an attempt towards a history of English literature,

Vol. 11 was completed after Morley's death by W. Hall Griffin.

Modern Greek stories,

"Demetra Vaka translated 'The sin of my mother,' 'The god-father' and 'She that was homesick.' The rest were translated by Dr. Aristides E. Phoutrides."