By means of a countermodel we show that the homotopy equivalence of the fibers of a Kan fibration over a connected base cannot be proved constructively.

BACKGROUND The increasing problem of multi-drug-resistant (MDR) tuberculosis (TB) [ie resistant to at least isoniazid (INH) and rifampicin (RIF)] is becoming a global problem. Successful treatment outcome for MDR-TB depends on reliable and accurate drug susceptibility testing of first-line and second-line anti-TB drugs. METHOD Consecutive M. tuberculosis isolates identified as MDR-TB during A...

In this study, a total of 77 multidrug-resistant and extensively drug-resistant (MDR and XDR, respectively) isolates of Mycobacterium tuberculosis were characterized among samples from patients living in Jiangxi province, China. The following two approaches were used: (i) genotyping all drug-resistant isolates by the 15-locus MIRU-VNTR (mycobacterial interspersed repetitive-unit-variable-number...

Two broad-host-range vectors previously constructed for use in soil bacteria (A. G. Matthysse, S. Stretton, C. Dandie, N. C. McClure, and A. E. Goodman, FEMS Microbiol. Lett. 145:87-94, 1996) were assessed by epifluorescence microscopy for use in tagging three marine bacterial species. Expression of gfp could be visualized in Vibrio sp. strain S141 cells at uniform levels of intensity from eith...

The Reproducibility Project: Cancer Biology seeks to address growing concerns about reproducibility in scientific research by conducting replications of selected experiments from a number of high-profile papers in the field of cancer biology. The papers, which were published between 2010 and 2012, were selected on the basis of citations and Altmetric scores (Errington et al., 2014). This Regist...

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 (strain 86-24) harbors a 3.3-kb plasmid (pSP70) that does not encode a selectable phenotype. A 1.1-kb fragment of DNA encoding kanamycin resistance (Kan(r)) was inserted by in vitro transposon mutagenesis at a random location on pSP70 to construct pSP70-Kan(r) that conferred Kan(r) to the host E. coli strain. Oligonucleotides complementary to 5'...

Amaç: Dikkat eksikliği ve hiperaktivite bozukluğu (DEHB) nedeniyle metilfenidat kullanan hastalarda nadiren kardiyovasküler yan etkiler görülebilmektedir. Bu çalışmada, DEHB’li hastalarda metilfenidatın kardiovasküler sistem üzerine etkilerininin araştırılması planlandı. Yöntem: Mayıs 2011-Mayıs 2012 tarihleri arasında DEHB tanısı ile metilfenidat tedavisi başlanan 141 hasta incelendi. Hastalar...

Cerebrospinal fluid (CSF) biomarkers may be used to identify and monitor pathological processes in the central nervous system. CSF biomarkers in Alzheimer’s disease (AD) include β-amyloid 42 (Aβ42), total-tau (T-tau) and phosphorylated-tau (P-tau), reflecting brain amyloid, axonal and tangle pathology, respectively. This dissertation aims at defining and validating CSF biomarkers for amyloid an...