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41.
Komiya Shiro Katsumata Mari Ozawa Moe Haze Tatsuya Kawano Rina Ohki Yuki Suzuki Shota Kobayashi Yusuke Fujiwara Akira Saka Sanae Tamura Kouichi Hirawa Nobuhito 《Clinical and experimental nephrology》2022,26(9):851-858
Clinical and Experimental Nephrology - Tolvaptan (TLV) is reported to improve diuretic effects in patients with chronic kidney disease (CKD) when furosemide (FUR) is not sufficiently effective.... 相似文献
42.
Contribution of equilibrative nucleoside transporters 1 and 2 to gemcitabine uptake in pancreatic cancer cells 下载免费PDF全文
Masato Hioki Takuya Shimada Tian Yuan Takeo Nakanishi Hidehiro Tajima Maiko Yamazaki Rina Yokono Makiko Takabayashi Kazuki Sawamoto Gaku Akashita Ken‐Ichi Miyamoto Tetsuo Ohta Ikumi Tamai Tsutomu Shimada Yoshimichi Sai 《Biopharmaceutics & drug disposition》2018,39(5):256-264
Hepatic arterial infusion (HAI) chemotherapy is expected to be a more effective and safer method to treat the hepatic metastasis of pancreatic cancer than intravenous (iv) administration because of higher tumor exposure and lower systemic exposure. To clarify the uptake mechanism of nucleoside anticancer drugs, including gemcitabine (GEM), in pancreatic cancer, we investigated the uptakes of radiolabeled uridine (a general substrate of nucleoside transporters) and GEM in pancreatic cancer cell lines MIA‐PaCa2 and As‐PC1. Uridine uptake was inhibited by non‐labeled GEM and also by S‐(4‐nitrobenzyl)‐6‐thioinosine (NBMPR; an inhibitor of equilibrative nucleoside transporters, ENTs) in a concentration‐dependent manner, suggesting that ENTs contribute to uridine uptake in pancreatic cancer cells. As for GEM, saturable uptake was mediated by high‐ and low‐affinity components with Km values of micromolar and millimolar orders, respectively. Uptake was inhibited in a concentration‐dependent manner by NBMPR and was sodium ion‐independent. Moreover, the concentration dependence of uptake in the presence of 0.1 μM NBMPR showed a single low‐affinity site. These results indicated that the high‐ and low‐affinity sites correspond to hENT1 and hENT2, respectively. The results indicated that at clinically relevant hepatic concentrations of GEM in GEM‐HAI therapy, the metastatic tumor exposure of GEM is predominantly determined by hENT2 under unsaturated conditions, suggesting that hENT2 expression in metastatic tumor would be a candidate biomarker for indicating anticancer therapy with GEM‐HAI. 相似文献
43.
C. A. Downs Esti Kramarsky-Winter John E. Fauth Roee Segal Omri Bronstein Rina Jeger Yona Lichtenfeld Cheryl M. Woodley Paul Pennington Ariel Kushmaro Yossi Loya 《Ecotoxicology (London, England)》2014,23(2):175-191
Benzophenone-2 (BP-2) is an additive to personal-care products and commercial solutions that protects against the damaging effects of ultraviolet light. BP-2 is an “emerging contaminant of concern” that is often released as a pollutant through municipal and boat/ship wastewater discharges and landfill leachates, as well as through residential septic fields and unmanaged cesspits. Although BP-2 may be a contaminant on coral reefs, its environmental toxicity to reefs is unknown. This poses a potential management issue, since BP-2 is a known endocrine disruptor as well as a weak genotoxicant. We examined the effects of BP-2 on the larval form (planula) of the coral, Stylophora pistillata, as well as its toxicity to in vitro coral cells. BP-2 is a photo-toxicant; adverse effects are exacerbated in the light versus in darkness. Whether in darkness or light, BP-2 induced coral planulae to transform from a motile planktonic state to a deformed, sessile condition. Planulae exhibited an increasing rate of coral bleaching in response to increasing concentrations of BP-2. BP-2 is a genotoxicant to corals, exhibiting a strong positive relationship between DNA-AP lesions and increasing BP-2 concentrations. BP-2 exposure in the light induced extensive necrosis in both the epidermis and gastrodermis. In contrast, BP-2 exposure in darkness induced autophagy and autophagic cell death. The LC50 of BP-2 in the light for an 8 and 24 h exposure was 120 and 165 parts per billion (ppb), respectively. The LC50s for BP-2 in darkness for the same time points were 144 and 548 ppb. Deformity EC20 levels (24 h) were 246 parts per trillion in the light and 9.6 ppb in darkness. 相似文献
44.
目的 分析超声各特征性影像表现在乳腺浸润性导管癌中的诊断价值。方法 选取解放军总医院第六医学中心 2018-01至2019-12两年内收治的 135例乳腺浸润性导管癌患者纳入本研究,分析乳腺浸润性导管癌的超声影像特征、体检自检发现率以及淋巴结转移与病变大小、位置的相关性。结果 (1)单因素分析显示:形态不规则(91.11%)、边界不清楚(64.44%)、血流信号(44.44%)、微钙化(37.78%)、纵横比>1(17.78%)、后方回声衰减(15.56%)超声诊断指标,与浸润性导管癌的诊断具有相关性;(2)与其他三个象限相比较,内上象限浸润性导管癌更容易被患者自检发现,占自检发现病例的34.93%;(3)内上象限及外上象限的浸润性导管癌更容易发生淋巴结转移(转移率为:内上:25.53%,内下:0.00%,外上:64.70%,外下:11.76%);(4)对<3 cm的浸润性导管癌,其大小与腋窝淋巴结的转移没有相关性。结论 超声表现以形态不规则在乳腺浸润性导管癌中的发生率最高,且在早期病变中即表现出来;乳腺病变的自检检出率、乳腺癌淋巴转移率均与乳腺病变的大小和位置密切相关。 相似文献
45.
Kadota Tamami Ogaya Yuko Hatakeyama Rina Nomura Ryota Nakano Kazuhiko 《Odontology / the Society of the Nippon Dental University》2019,107(2):261-267
Odontology - The oral cavity is recognized as a major route for infection by Helicobacter pylori, which colonizes the gastric mucosa. Therapeutic options for elimination in patients with digestive... 相似文献
46.
Tomohiro Fukuda Makoto Naganuma Kaoru Takabayashi Yuya Hagihara Shun Tanemoto Ena Nomura Yusuke Yoshimatsu Shinya Sugimoto Kosaku Nanki Shinta Mizuno Yohei Mikami Kayoko Fukuhara Tomohisa Sujino Makoto Mutaguchi Nagamu Inoue Haruhiko Ogata Yasushi Iwao Takayuki Abe Takanori Kanai 《Journal of gastroenterology and hepatology》2020,35(11):1878-1885
47.
Isac Silva de Jesus Rina Lourena da Silva Medeiros Marta Margarete Cestari Marcos de Almeida Bezerra Paulo Roberto Antunes de Mello Affonso 《Bulletin of environmental contamination and toxicology》2014,92(5):551-556
Samples of two carnivore fish species (Hoplias malabaricus and Serrasalmus brandtii) were collected along Contas River, northeastern Brazil, to determine the levels of Co, Cr, Cu, Fe, Mn, Ni and Pb in edible and non-edible tissues of these important local fisheries resources. Lead could not be quantified in most of the samples, while the other metals were detected in both species. In edible parts, Cr levels were above Brazilian threshold limits in all specimens and Ni was at high concentration in S. brandtii individuals from one collection site. In non-edible parts (viscera), besides Cr, Cu concentration was higher than that recommended by Brazilian laws. Both fish species proved to be sensitive to environmental contamination. Despite the different ecological characteristics, such as vagility and feeding strategy, these fish showed that aquatic predators are efficient bioindicators of water quality and biomagnification. 相似文献
48.
Nicola Montano Fabio Papacci Beatrice Cioni Rina Di Bonaventura Mario Meglio 《Acta neurologica Belgica》2014,114(1):59-64
Trigeminal neuralgia (TN) recurring after surgery can be difficult to treat. Treatment algorithms have not been standardized or universally accepted. Here we investigated the effectiveness of percutaneous balloon compression (PBC) in the treatment of patients with TN recurrence after other surgical techniques and analyzed the role of some clinical and operative factors in determining the prognosis. The records of 22 patients (13 M and 9 F) suffering recurrent TN after one (2 gamma knife surgery, 5 percutaneous radiofrequency rhizotomy, 6 percutaneous retrogasserian glycerol rhizotomy, 3 microvascular decompression) or more (6 patients) procedures and submitted to PBC at our institution from January 2003 to February 2012 were reviewed. Seven patients had TN related to multiple sclerosis (MS). Mean follow-up was 51.81 ± 26.63 months. 81.81 % of patients reported an acute pain relief. No major complication was observed after PBC. Eight patients (36.36 %) experienced pain recurrence and underwent one (five patients) or more (three patients) PBC. At the last follow-up, we obtained an excellent outcome (BNI I–II) in 16 patients out of 22 (72.72 %) and a good outcome (BNI III) in the remaining six. No patients had an uncontrolled pain. The lack of history of MS (p = 0.0174), the pear-like shape of the balloon at the operation (p = 0.0234) and a compression time <5 min (p < 0.05) were associated to higher pain-free survival. Considering these results PBC could be considered a useful technique for patients whose pain recurs after other procedures. 相似文献
49.
50.
Ram Prasad Bhusal Pramod Aryal Shankar Raj Devkota Rina Pokhrel Menachem J. Gunzburg Simon R. Foster Herman D. Lim Richard J. Payne Matthew C. J. Wilce Martin J. Stone 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(9)
As natural chemokine inhibitors, evasin proteins produced in tick saliva are potential therapeutic agents for numerous inflammatory diseases. Engineering evasins to block the desired chemokines and avoid off-target side effects requires structural understanding of their target selectivity. Structures of the class A evasin EVA-P974 bound to human CC chemokine ligands 7 and 17 (CCL7 and CCL17) and to a CCL8-CCL7 chimera reveal that the specificity of class A evasins for chemokines of the CC subfamily is defined by conserved, rigid backbone–backbone interactions, whereas the preference for a subset of CC chemokines is controlled by side-chain interactions at four hotspots in flexible structural elements. Hotspot mutations alter target preference, enabling inhibition of selected chemokines. The structure of an engineered EVA-P974 bound to CCL2 reveals an underlying molecular mechanism of EVA-P974 target preference. These results provide a structure-based framework for engineering evasins as targeted antiinflammatory therapeutics.While some proteins exhibit absolute specificity for a unique binding partner, many others display “multispecificity,” whereby they interact with several, but not all, members of a partner protein family (1, 2). Understanding how proteins achieve such selectivity provides a basis for rational engineering to regulate alternative targets. In this study, we investigated the structural basis for multispecific recognition of human proinflammatory chemokines by tick evasin proteins.Chemokines are the master regulators of leukocyte-trafficking, the unifying feature of immune homeostasis and all inflammatory diseases (3). Chemokines stimulate leukocyte migration via activation of chemokine receptors, G protein–coupled receptors expressed on the surfaces of leukocytes. Chemokines are classified into two major families (CCL and CXCL) and two minor families (XCL and CX3CL) based on the arrangement of conserved cysteine residues near the N termini of their amino acid sequences. Chemokine receptors are classified (CCR, CXCR, XCR, and CX3CR) based on their chemokine selectivity. The types of leukocytes recruited to specific tissues depend on the array of chemokines expressed in those tissues and the selectivity of those chemokines for the receptors expressed on different leukocyte subsets. For example, in vascular inflammation associated with hypertension, elevated levels of the chemokines CCL2, CCL7, and CCL8 act via the receptor CCR2 (and possibly also CCR1) to stimulate migration of monocytes into the blood vessel wall (4).To suppress leukocyte recruitment in inflammatory diseases, numerous antagonists of specific chemokine receptors have been evaluated in clinical trials. However, these trials have not yielded any new antiinflammatory therapeutics (5), in part because most leukocytes can utilize multiple chemokine receptors, thus circumventing the specific antagonists. The alternative approach of targeting chemokines has not generally been favored, because it would require agents that bind with high affinity to multiple chemokines. However, the natural chemokine-binding proteins of ticks, helminths, and viruses (6–8) display multispecificity for mammalian chemokines, suggesting that they could potentially be deployed as antiinflammatory therapeutics.Evasins are two families of chemokine-binding, antiinflammatory proteins from tick saliva (6). Class A evasins each inhibit multiple CC chemokines of their mammalian hosts but none of the closely related CXC chemokines. Conversely, class B evasins are specific for CXC over CC chemokines but exhibit variable selectivity among CXC chemokines. Typically, each tick species secretes a mixture of evasins, thereby accomplishing broad-spectrum suppression of the host inflammatory response, presumably enabling the tick to feed on the host for extended periods.The in vivo antiinflammatory activity of tick evasins has been demonstrated using a variety of animal models of inflammatory diseases, including lung fibrosis, skin inflammation, arthritis, colitis, pancreatitis, ischemic reperfusion injury, postinfarction myocardial injury, and Leishmania major infection (9–13). However, deploying evasins as effective antiinflammatory therapeutics in humans would require engineering the natural evasins to selectively target the relevant array of chemokines for any given indication while minimizing off-target inhibition (14). Such engineering requires understanding both the specificity of evasins for a single chemokine subfamily and their target preference among chemokines within that subfamily.Previously, only a single structure has been reported for an evasin:chemokine complex, class A evasin EVA-1 bound to CCL3 (15), so it has not been possible to identify the conserved and variable features of the interactions. Nevertheless, the structure revealed that EVA-1 binds to several receptor recognition elements of CCL3, explaining its inhibitory activity. Moreover, limited mutational data (15, 16) have confirmed that residues in the N- and C-terminal regions of EVA-1 and the homologous EVA-4, respectively, contribute to binding affinity, raising the question of whether the structural basis of CC chemokine recognition varies across the class A evasin family.To establish a structure-based platform for engineering the chemokine selectivity of class A evasins, we now report the structures of EVA-P974 (previously called ACA-01) (17, 18), from the Cayenne tick (Amblyomma cajennense), bound to each of two wild-type chemokines and one chimeric CC chemokine. Structural comparisons and extensive evasin and chemokine mutational data revealed the structural basis for CC chemokine specificity and identified several “hotspots” that define target preference among CC chemokines. These insights enabled EVA-P974 to be engineered to modify its target preference. We further verified the molecular basis of the modified selectivity by solving the chemokine-bound structure of the engineered evasin. Finally, by inhibiting a chemokine mixture, we provide proof of principle for applying engineered evasins as multichemokine inhibitors. 相似文献