Awareness of Complications of Dental Treatment in Patients Treated with Drugs Affecting the Immune System : A Nationwide Questionnaire Survey of Dental Practitioners in Japan

The aim of this study was to investigate the awareness and experience, among dental practitioners, of adverse events resulting from dental treatment of patients undergoing therapy with drugs that affect the immune system [angiogenesis inhibitors, biological agents, immunosuppressants, and disease-modifying anti-rheumatic drugs (DMARDs)]. For this purpose, a nationwide questionnaire survey was conducted. Questionnaires were sent to 2,050 dentists, of which 206 (10.1%) were completed and returned. The results showed that most dentists were aware of complications associated with dental treatment of patients treated with drugs that affect the immune system, and about half had actually experienced such complications. Delayed wound healing, osteonecrosis of the jaw (ONJ), and postoperative infections were reported. Whereas approximately 50% of dentists did not discontinue the drugs during dental treatment, about 18% did. During temporary drug discontinuation, some patients experienced aggravation of the primary disease, such as worsening of rheumatism, growth of tumors, and rejection reactions of transplanted organs. As for medical cooperation, only less than half of the dentists were asked for oral hygiene management by a physician prior to starting the drug treatment. Prospective studies are needed because evidence for dental treatments in patients treated with these drugs remains limited

Strain-Dependent Prion Infection in Mice Expressing Prion Protein with Deletion of Central Residues 91–106

Conformational conversion of the cellular prion protein, PrPC, into the abnormally folded isoform, PrPSc, is a key pathogenic event in prion diseases. However, the exact conversion mechanism remains largely unknown. Transgenic mice expressing PrP with a deletion of the central residues 91–106 were generated in the absence of endogenous PrPC, designated Tg(PrPΔ91–106)/Prnp0/0 mice and intracerebrally inoculated with various prions. Tg(PrPΔ91–106)/Prnp0/0 mice were resistant to RML, 22L and FK-1 prions, neither producing PrPScΔ91–106 or prions in the brain nor developing disease after inoculation. However, they remained marginally susceptible to bovine spongiform encephalopathy (BSE) prions, developing disease after elongated incubation times and accumulating PrPScΔ91–106 and prions in the brain after inoculation with BSE prions. Recombinant PrPΔ91-104 converted into PrPScΔ91–104 after incubation with BSE-PrPSc-prions but not with RML- and 22L–PrPSc-prions, in a protein misfolding cyclic amplification assay. However, digitonin and heparin stimulated the conversion of PrPΔ91–104 into PrPScΔ91–104 even after incubation with RML- and 22L-PrPSc-prions. These results suggest that residues 91–106 or 91–104 of PrPC are crucially involved in prion pathogenesis in a strain-dependent manner and may play a similar role to digitonin and heparin in the conversion of PrPC into PrPSc

Türkçeden garp dillerine tercümeler

Taha Toros Arşivi, Dosya Adı: Namık Kemalİstanbul Kalkınma Ajansı (TR10/14/YEN/0033) İstanbul Development Agency (TR10/14/YEN/0033

Phase separation of an actin nucleator by junctional microtubules regulates epithelial function

Liquid-liquid phase separation (LLPS) is involved in various dynamic biological phenomena. In epithelial cells, dynamic regulation of junctional actin filaments tethered to the apical junctional complex (AJC) is critical for maintaining internal homeostasis against external perturbations; however, the role of LLPS in this process remains unknown. Here, after identifying a multifunctional actin nucleator, cordon bleu (Cobl), as an AJC-enriched microtubule-associated protein, we conducted comprehensive in vitro and in vivo analyses. We found that apical microtubules promoted LLPS of Cobl at the AJC, and Cobl actin assembly activity increased upon LLPS. Thus, microtubules spatiotemporally regulated junctional actin assembly for epithelial morphogenesis and paracellular barriers. Collectively, these findings established that LLPS of the actin nucleator Cobl mediated dynamic microtubule-actin cross-talk in junctions, which fine-tuned the epithelial barrier

The Role of the OR Region in BSE Pathogenesis

Conformational conversion of the cellular isoform of prion protein PrPC, into the abnormally folded, amyloidogenic isoform, PrPSc, is a key pathogenic event in prion diseases including Creutzfeldt-Jakob disease in humans and scrapie and bovine spongiform encephalopathy (BSE) in animals. We previously reported that the octapeptide repeat (OR) region could be dispensable for converting PrPC into PrPSc after infection with RML prions. We demonstrated that mice transgenically expressing mouse PrP with deletion of the OR region on the PrP-knockout background, designated Tg(PrPΔOR)/Prnp0/0 mice, did not reduced susceptibility to RML scrapie prions, with abundant accumulation of PrPScΔOR in their brains. We show here that Tg(PrPΔOR)/Prnp0/0 mice were highly resistant to BSE prions, developing the disease with markedly elongated incubation times after infection with BSE prions. The conversion of PrPΔOR into PrPScΔOR was markedly delayed in their brains. These results suggest that the OR region may have a crucial role in the conversion of PrPC into PrPSc after infection with BSE prions. However, Tg(PrPΔOR)/Prnp0/0 mice remained susceptible to RML and 22L scrapie prions, developing the disease without elongated incubation times after infection with RML and 22L prions. PrPScΔOR accumulated only slightly less in the brains of RML- or 22L-infected Tg(PrPΔOR)/Prnp0/0 mice than PrPSc in control wild-type mice. Taken together, these results indicate that the OR region of PrPC could play a differential role in the pathogenesis of BSE prions and RML or 22L scrapie prions. IMPORTANCE Structure-function relationship studies of PrPC conformational conversion into PrPSc are worthwhile to understand the mechanism of the conversion of PrPC into PrPSc. We show here that, by inoculating the three different prion strains of RML, 22L and BSE prions, into Tg(PrP∆OR)/Prnp0/0 mice, the OR region could play a differential role in the conversion of PrPC into PrPSc after infection with RML or 22L scrapie prions and BSE prions. PrPΔOR was efficiently converted into PrPScΔOR after infection with RML and 22L prions. However, the conversion of PrPΔOR into PrPScΔOR was markedly delayed after infection with BSE prions. Further investigation into the role of the OR region in the conversion of PrPC into PrPSc after infection with BSE prions might be helpful for understanding the pathogenesis of BSE prions

速度論に基づくマウス脂肪細胞分化過程の解析

It is possible to determine rate kinetic constants for cell-differential processes in vivo through the measurement of the transcription-ratio of some genes by real-time PCR(1). In the previous paper, the differentiation of adipocytes was investigated and rate constants for the processes, at which PPARγ-expressing cells differentiated into AD(adiponectin)- or Re(resistin)-expressing cells, were determined in the thymus of BALB/c mouse(2). In this paper, the rate constant for the process of PPARγ-expressing cells changing to HSL(hormone sensitive lipase)-expressing cells. Considering both results, it was concluded that PPARγexpressing cells change to express HSL firstly, AD secondly and then Re in adipocytes-differential processBALB/cマウスの胸腺での脂肪細胞の分化過程を,PPARγ(PP)に対するホルモン感受性リパーゼ(HSL)の転写量を指標として,リアルタイムPCR法により検討した。　PPに対するHSLの転写量比は,生後直後は1より小さかったが,その後増大し一定値となった。この加齢変化を,遺伝子の転写量は,その転写細胞数に比例すると仮定することにより,また,脂肪細胞系列の幹細胞を考えることにより,速度論により説明することができた。この速度論に基づく方法は,細胞の分化過程で発現する遺伝子の発現順を決定することに応用できることを示した

Yokukansan Inhibits Neuronal Death during ER Stress by Regulating the Unfolded Protein Response

Recently, several studies have reported Yokukansan (Tsumura TJ-54), a traditional Japanese medicine, as a potential new drug for the treatment of Alzheimer's disease (AD). Endoplasmic reticulum (ER) stress is known to play an important role in the pathogenesis of AD, particularly in neuronal death. Therefore, we examined the effect of Yokukansan on ER stress-induced neurotoxicity and on familial AD-linked presenilin-1 mutation-associated cell death.We employed the WST-1 assay and monitored morphological changes to evaluate cell viability following Yokukansan treatment or treatment with its components. Western blotting and PCR were used to observe the expression levels of GRP78/BiP, caspase-4 and C/EBP homologous protein.Yokukansan inhibited neuronal death during ER stress, with Cnidii Rhizoma (Senkyu), a component of Yokukansan, being particularly effective. We also showed that Yokukansan and Senkyu affect the unfolded protein response following ER stress and that these drugs inhibit the activation of caspase-4, resulting in the inhibition of ER stress-induced neuronal death. Furthermore, we found that the protective effect of Yokukansan and Senkyu against ER stress could be attributed to the ferulic acid content of these two drugs.Our results indicate that Yokukansan, Senkyu and ferulic acid are protective against ER stress-induced neuronal cell death and may provide a possible new treatment for AD

Effects of NK-4 in a Transgenic Mouse Model of Alzheimer's Disease

Beta-amyloid (Aβ) peptides are considered to play a major role in the pathogenesis of Alzheimer's disease (AD) and molecules that can prevent pathways of Aβ toxicity may be potential therapeutic agents for treatment of AD. We have previously reported that NK-4, a cyanine photosensitizing dye, displays neurotrophic and antioxidant activities. In this study, we report the effects of NK-4 on the toxicity of Aβ and on cognitive function and Aβ concentration in a transgenic mouse model of AD (Tg2576). In vitro, NK-4 effectively protected neuronal cells from toxicity induced by Aβ. In addition, it displayed profound inhibitory activities on Aβ fibril formation. In vivo, Tg2576 mice received an intraperitoneal injection at 100 or 500 µg/kg of NK-4 once a day, five times a week for 9 months. Administration of NK-4 to the mice attenuated impairment of recognition memory, associative memory, and learning ability, as assessed by a novel object recognition test, a passive avoidance test, and a water maze test, respectively. NK-4 decreased the brain Aβ concentration while increasing the plasma amyloid level in a dose-dependent manner. NK-4 also improved memory impairments of ICR mice induced by direct intracerebroventricular administration of Aβ. These lines of evidence suggest that NK-4 may affect multiple pathways of amyloid pathogenesis and could be useful for treatment of AD