2,406 research outputs found

    Adriamycin-loaded albumin-heparin conjugate microspheres for intraperitoneal chemotherapy

    Get PDF
    Adriamycin-loaded albumin-heparin conjugate microspheres (ADR-AHCMS) were evaluated as possible intraperitoneal (i.p.) delivery systems for site-specific cytotoxic action. The biocompatibility of the microspheres after intraperitoneal injection was tested first. 1 day after i.p. administration of empty as well as drug-loaded AHCMS to male Balb/c mice, only a moderate increase in i.p. neutrophils was measured. 3 days after injection neutrophil levels were comparable with the controls. No significant increases in the numbers of other cell types were observed, indicating an acute inflammatory response which can be considered to be mild. Antitumour efficacy was tested in an L1210 tumour-bearing mouse model and in a CC531 tumour-bearing rat model. The use of ADR-AHCMS leads to longer survival times of mice and improved tumour growth delay in rats, as compared with untreated controls and free drug treated animals. In both animal models higher adriamycin doses were initially tolerated if the drug was formulated in microspheres, although long-term adriamycin toxicity effects were evident in all treated groups. Doses and dosage schedules may be optimized to further reduce the toxic effects of the drug

    Gating the pore of the calcium-activated chloride channel TMEM16A

    Get PDF
    The binding of cytoplasmic Ca2+ to the anion-selective channel TMEM16A triggers a conformational change around its binding site that is coupled to the release of a gate at the constricted neck of an hourglass-shaped pore. By combining mutagenesis, electrophysiology, and cryo-electron microscopy, we identified three hydrophobic residues at the intracellular entrance of the neck as constituents of this gate. Mutation of each of these residues increases the potency of Ca2+ and results in pronounced basal activity. The structure of an activating mutant shows a conformational change of an α-helix that contributes to Ca2+ binding as a likely cause for the basal activity. Although not in physical contact, the three residues are functionally coupled to collectively contribute to the stabilization of the gate in the closed conformation of the pore, thus explaining the low open probability of the channel in the absence of Ca2+

    T5lephone: Bridging Speech and Text Self-supervised Models for Spoken Language Understanding via Phoneme level T5

    Full text link
    In Spoken language understanding (SLU), a natural solution is concatenating pre-trained speech models (e.g. HuBERT) and pretrained language models (PLM, e.g. T5). Most previous works use pretrained language models with subword-based tokenization. However, the granularity of input units affects the alignment of speech model outputs and language model inputs, and PLM with character-based tokenization is underexplored. In this work, we conduct extensive studies on how PLMs with different tokenization strategies affect spoken language understanding task including spoken question answering (SQA) and speech translation (ST). We further extend the idea to create T5lephone(pronounced as telephone), a variant of T5 that is pretrained using phonemicized text. We initialize T5lephone with existing PLMs to pretrain it using relatively lightweight computational resources. We reached state-of-the-art on NMSQA, and the T5lephone model exceeds T5 with other types of units on end-to-end SQA and ST
    • …
    corecore