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991.
Mari Hiraoka Kenichi Inoue Haruki Senoo Masahiko Takada 《Anatomical record (Hoboken, N.J. : 2007)》2015,298(3):630-636
For more than a century there has been debate concerning the mechanism of accommodation—whether the lens capsule or lens material itself determines the functional relationship between ciliary muscle contractility and lens deformation during refractive adaptation. This morphological study in monkey eyes investigates the composition and distribution of several connective tissue components in the accommodative apparatus relaying muscle force to lens organization. Elastin distributes on the marginal surface of the ciliary process. A zonule is composed of fibrillin produced by epithelial cells of the process. In the progress of extension over the posterior chamber, fibrils unite into strands and possess longitudinal plasticity. By induction of the elastin network, strands extend in a concentric direction covering the equatorial region of the capsule. Upon tethering to the lens, the strand ramifies into fibrils, penetrating deeply close to the epithelial layer of the lens and binding with the collagen of the intercellular spaces. Tight linkage of the zonule with the capsule transmits precise contractility. Inside the lens, the cortical layer's elastic connective tissue network forms widely spaced lamellae of crystalline fibers. In contrast, the central nuclear lamellae are tightly opposed. The accumulation of lamellae is greater in the anterior cortex than in the posterior, yielding a more variable anterior chamber depth in the visual axis. The plasticity of the zonule and connective tissue distribution inside the lens produces an adjustable configuration. Thus, tight linkage between the dynamism of the capsule with interaction of the lenticular flexibility provides a novel understanding of accommodation. Anat Rec, 298:630–636, 2015. © 2014 The Authors The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology Published by Wiley Periodicals, Inc. 相似文献
992.
The recent emergence of stem cell-based tissue engineering has now opened up new venues for gene therapy. The task now is
to develop safe and effective vectors that can deliver therapeutic genes into specific stem cell lines and maintain long-term
regulated expression of these genes. Human artificial chromosomes (HACs) possess several characteristics that require gene
therapy vectors, including a stable episomal maintenance, and the capacity for large gene inserts. HACs can also carry genomic
loci with regulatory elements, thus allowing for the expression of transgenes in a genetic environment similar to the chromosome.
Currently, HACs are constructed by a two prone approaches. Using a top-down strategy, HACs can be generated from fragmenting
endogenous chromosomes. By a bottom-up strategy, HACs can be created de novo from cloned chromosomal components using chromosome engineering. This review describes the current advances in developing
HACs, with the main focus on their applications and potential value in gene delivery, such as HAC-mediated gene expression
in embryonic, adult stem cells, and transgenic animals. 相似文献
993.
Yoshinari M Matsuzaka K Inoue T Oda Y Shimono M 《Journal of biomedical materials research. Part A》2003,65(3):359-368
Microgrooves have been investigated as substrates for the control of cell alignment. However, they are relatively too narrow and shallow for controlling the orientation of extracellular matrices (ECM) such as collagen. Multigrooves, a combination of microgrooves and macrogrooves, are expected to be able to control the orientation of both cells and ECM. This study investigated a method for fabricating multigrooves and evaluated fibroblast behavior on these novel surfaces. Multigrooved patterns were fabricated on a gold-alloy metal die, in which 90-degree V-shaped microgrooves with a 2-microm pitch were cut on trapezoidal macrogrooves. The macrogrooves had a 50- microm ridge width, a 50-microm wall width, a 50-microm bottom width, and a 25-microm depth. The grooves were made by an ultraprecision micromachine using a single crystal diamond. This metal die served as a template for making surface replicas from polystyrene. Microgrooved and smooth polystyrene replicas also were prepared as comparative substrates. Mouse fibroblast L929 cells were cultured in each type of replica substrate for 7 to 21 days. After these periods, the cells were fixed with 2.5% glutaraldehyde, treated with conventional methods, and, finally, observed by SEM. Confocal laser scanning microscopy was performed to investigate ECM formation. The multigrooved metal die exhibited the desired sharp configuration without defects. The dimensional values of the multigrooves on the polystyrene replicas were almost the same as the designed values. The fibroblasts on the multigrooved and microgrooved substrates were aligned parallel to the surface grooves after 7 days of incubation. In contrast to the microgrooved and flat surfaces, a dense extracellular matrix was produced along the multigrooves after 21 days of incubation. These results suggest that multigrooves can control the orientation of ECM as well as cells and thus enhance the production of ECM. 相似文献
994.
BACKGROUND: Goblet cell metaplasia is a pathologic characteristic of asthma, associated with excess mucus secretion. Interleukin (IL)-4 and IL-13 plays an important role in mucus hypersecretion. Suplatast tosilate (suplatast), an antiallergic agent, is a Th2 cytokine inhibitor that suppresses the synthesis of IL-4, IL-5, IL-13, and eosinophilic airway inflammation. OBJECTIVE: We examined the effects of suplatast on mucus production in bronchial biopsy specimens taken from asthmatic subjects. METHODS: Oral suplatast 300 mg daily, or placebo was administered for 3 months in a double-blind, parallel-group study in 25 patients with asthma. Biopsy specimens were evaluated at before and after treatment for alcian blue/period acid-Schiff (AB/PAS), MUC5AC staining in bronchial epithelium and IL-4+, IL-13+ cells as well as inflammatory cells in lamina propria. RESULTS: There were significant decreases in the percentage of AB/PAS (P < 0.01) and MUC5AC (P < 0.01) stained area in the suplatast group. These changes were accompanied by significant decreases in IL-4+ and IL-13+ cells in suplatast-treated subjects. Additionally, we have observed that the number of infiltrating eosinophils and CD4+ T cells significantly decreased. CONCLUSIONS: These findings suggest that suplatast prevents goblet cell metaplasia through modulation of Th2 cytokine production and the recruitment of eosinophils and CD4+ T cells in the asthmatic airways. 相似文献
995.
996.
The mechanism of cocaine-related sudden death is unknown. To test whether cocaine potentiated changes in sinus cycle length, conduction in the atrioventricular node (AH interval) and ventricular effective refractory period induced by infused norepinephrine and ansae subclaviae stimulation, the dose-response curves of sinus cycle length, AH interval and ventricular effective refractory period to infused norepinephrine (0.01 to 0.20 micrograms/kg body weight per min) and the frequency-response curves to ansae subclaviae stimulation (1 to 4 Hz, 2 to 3 mA, 4 ms pulses) were determined before and after intravenous injection of cocaine (5 mg/kg) in 15 anesthetized open chest dogs. Cocaine potentiated shortening of sinus cycle length, AH interval and ventricular effective refractory period induced by norepinephrine infusion and shifted dose-response curves of these variables to the left in eight dogs (supersensitivity). Cocaine did not affect frequency-response curves of sinus cycle length and AH interval to ansae subclaviae stimulation. Ansae subclaviae stimulation shortened the ventricular effective refractory period more after cocaine injection, but frequency-response curves were not shifted to the left in seven dogs (no supersensitivity). Cocaine did not enhance electrical induction of ventricular tachyarrhythmias in 15 dogs without acute myocardial infarction. Acute myocardial infarction was produced by coronary artery ligation in another group of 21 dogs. Of 10 dogs with acute myocardial infarction, spontaneous or electrically induced ventricular tachycardia developed in 1 dog without drugs, in 3 dogs given norepinephrine and in 7 dogs given norepinephrine and cocaine (p less than 0.03 versus without drugs).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
997.
Zhongzhi?Wang Masatoshi?JinninEmail author Miho?Harada Hideo?Kudo Kuniko?Inoue Wakana?Nakayama Noritoshi?Honda Katsunari?Makino Ikko?Kajihara Satoshi?Fukushima Hironobu?Ihn 《European journal of dermatology : EJD》2017,27(1):20-27
Background
MicroRNA levels in sera or hair may potentially be useful biomarkers for various diseases. The diagnosis of nail diseases is sometimes difficult, and nail psoriasis without skin lesions is indistinguishable from nail changes caused by other diseases.Objectives
We evaluated nail microRNA levels as biomarkers for the diagnosis of psoriasis patients.Materials & methods
MicroRNA levels were examined in psoriasis patients with (11 patients) and without (six patients) nail changes. Normal control nails were collected from 17 healthy subjects. Eight patients with other diseases who also had nail changes were also included as disease controls.Results
Microarray, real-time PCR, and in situ hybridisation indicated that the expression levels of nail miR- 4454 were decreased in psoriasis patients with nail changes, compared to those patients with other diseases involving nail change, or healthy subjects. The miR-4454 levels in nails showed a significant inverse correlation with the Nail Psoriasis Severity Index (NAPSI) score, suggesting that nail miR-4454 levels reflect nail condition.Conclusion
The levels of microRNAs in nails may be suitable biomarkers for diagnosis or evaluation of disease activity of psoriasis.998.
Kohei Saito Tatsuhide Inoue Hiroyuki Ariyasu Toshio Shimada Hiroshi Itoh Issei Tanaka Chikashi Terao 《Journal of diabetes investigation.》2022,13(4):706
Aims/IntroductionWe aimed to replicate a new diabetes subclassification based on objective clinical information at admission in a diabetes educational inpatient program. We also assessed the educational outcomes for each cluster.MethodsWe included diabetes patients who participated in the educational inpatient program during 2009–2020 and had sufficient clinical information for the cluster analysis. We applied a data‐driven clustering method proposed in a previous study and further evaluated the clinical characteristics of each cluster. We investigated the association between the clusters and changes in hemoglobin A1c level from the start of the education program. We also assessed the risk of re‐admission for the educational program.ResultsWe divided a total of 651 patients into five clusters. Their clinical characteristics followed the same pattern as in previous studies. The intercluster ranking of the cluster center coordinates showed strong correlation coefficients with those of the previous studies (mean ρ = 0.88). Patients classified as severe insulin‐resistant diabetes (cluster 3) showed a more pronounced progression of renal dysfunction than patients classified as the other clusters. The patients classified as severe insulin‐deficient diabetes (cluster 2) had the highest rate of reduction in hemoglobin A1c level from the start of the program (P < 0.01) and a tendency toward a lower risk of re‐admission for the education program (hazard ratio 0.47, P = 0.09).ConclusionWe successfully replicated the diabetes subclassification using objective clinical information at admission for the education program. In addition, we showed that severe insulin‐deficient diabetes patients tended to have better educational outcomes than patients classified as the other clusters. 相似文献
999.
Analysis of treatment goal alignment between Japanese psoriasis patients and their paired treating physicians 下载免费PDF全文
Y. Okubo D. Tsuruta A.C. Tang S. Inoue H. Torisu‐Itakura T. Hanada M. Ohtsuki 《Journal of the European Academy of Dermatology and Venereology》2018,32(4):606-614
Background
Appropriate goal‐oriented treatment strategies are important for optimal treatment outcomes and may prevent under‐treatment. As treatment goals vary by patient, a study to examine treatment goals is more meaningful when patients and their physicians are paired. There has not been any study that examines alignment between paired psoriasis patients and physicians in real‐world clinical practice using skin clearance as a treatment goal indicator.Objectives
To evaluate treatment goal alignment between psoriasis patients and their paired physicians, and to quantitatively identify factors associated with goal misalignment.Methods
The study was a nationwide multicenter cross‐sectional observational study. Subjects were physician‐reported moderate‐to‐severe psoriasis patients with a history of systemic treatments, directly paired with their treating physicians. Subjects completed surveys independently. Treatment goals included seven categories, and patient–physician pairs were grouped as ‘aligned’ or ‘misaligned’ when the answers were the same or different, respectively.Results
A total of 425 pairs (mean response rate, 94.7%) of responses were collected from 54 sites (64.8% general practitioners or clinics; 35.2% university or large hospitals). Treatment goal misalignment was found in 67.9% of the patient–physician pairs. The misalignment was mainly ‘patient predominant’ (60.9%) indicating that patients had higher goals (‘complete clearance’) than physicians. In the multivariate logistic regression analyses, patients’ treatment expectation for ‘complete clearance’ [odds ratio (OR): 1.927; 95% confidential interval (CI): 1.232–3.016] and physician rating of ‘level of understanding on treatment options’ being low (OR: 1.552, 95% CI; 1.082–2.227) were significant factors for treatment goal misalignment.Conclusions
The majority of treatment goal misalignment was found between paired psoriasis patients and their treating physicians in Japan. The most important contributing factors to misalignment were patients’ treatment expectation for ‘complete clearance’ and physicians’ rating of their patients’ ‘level of understanding on treatment options’ being low. 相似文献1000.
Yuichiro Yoshino Mikio Ohtsuka Masakazu Kawaguchi Keisuke Sakai Akira Hashimoto Masahiro Hayashi Naoki Madokoro Yoshihide Asano Masatoshi Abe Takayuki Ishii Taiki Isei Takaaki Ito Yuji Inoue Shinichi Imafuku Ryokichi Irisawa Masaki Ohtsuka Fumihide Ogawa Takafumi Kadono Tamihiro Kawakami Ryuichi Kukino Takeshi Kono Masanari Kodera Masakazu Takahara Miki Tanioka Takeshi Nakanishi Yasuhiro Nakamura Minoru Hasegawa Manabu Fujimoto Hiroshi Fujiwara Takeo Maekawa Koma Matsuo Osamu Yamasaki Andres Le Pavoux Takao Tachibana Hironobu Ihn The Wound/Burn Guidelines Committee 《The Journal of dermatology》2016,43(9):989-1010
Burns are a common type of skin injury encountered at all levels of medical facilities from private clinics to core hospitals. Minor burns heal by topical treatment alone, but moderate to severe burns require systemic management, and skin grafting is often necessary also for topical treatment. Inappropriate initial treatment or delay of initial treatment may exert adverse effects on the subsequent treatment and course. Therefore, accurate evaluation of the severity and initiation of appropriate treatment are necessary. The Guidelines for the Management of Burn Injuries were issued in March 2009 from the Japanese Society for Burn Injuries as guidelines concerning burns, but they were focused on the treatment for extensive and severe burns in the acute period. Therefore, we prepared guidelines intended to support the appropriate diagnosis and initial treatment for patients with burns that are commonly encountered including minor as well as moderate and severe cases. Because of this intention of the present guidelines, there is no recommendation of individual surgical procedures. 相似文献