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We describe the influence of competing self-organizing phenomena on the formation of cholesteric mesophase in liquid crystalline brush block terpolymers (LCBBTs) and liquid crystalline random brush terpolymers (LCRBTs) containing chromonic molecules. A library of LCBBTs and LCRBTs are synthesized using ring-opening metathesis polymerization (ROMP) of norbornene side-chain functionalized monomers comprising cholesteryl mesogen (NBCh9), chromonic xanthenone (NBXan), and poly(ethylene glycol) (NBMPEG). Compression molded films of LCRBTs containing chromonic molecules display multilevel hierarchical structure in which cholesteric mesophase co-exists with π–π stacking of the chromonic mesophase along with PEG microphase segregated domains. This is unexpected as conventional LCBCPs and LCBBCs that lack chromonic molecules do not form cholesteric mesophases. The presence of π–π interactions modifies the interface at the IMDS so that both chromonic and cholesteric mesophases coexist leading to the manifestation of cholesteric phase for the first time within block architecture and is very reminiscent of previously published LCRBCs without chromonic molecules. The key to the observed hierarchical assembly in these LCBBTs containing chromonic molecules lies in the interplay of LC order, chromonic π–π stacking, PEG side chain microphase segregation, and their supramolecular cooperative motion. This unique “single component” polymer scaffold transforms our capacity to attain nanoscale hierarchies and optical properties from block architecture similar to nanoscale mesophases resulting in random architecture.We describe the influence of competing self-organizing phenomena on the formation of cholesteric mesophase in liquid crystalline brush block terpolymers (LCBBTs) and liquid crystalline random brush terpolymers (LCRBTs) containing chromonic molecules. 相似文献
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Sema HEPEN Pnar AKHANLI Hakan DÜER Murat ALAPKULU Bekir UAN Muhammed Erkam SENCAR Davut SAKIZ lknur
ZTÜRK ÜNSAL Seyit Murat BAYRAM Mustafa
ZBEK Erman AKAL 《Turkish Journal of Medical Sciences》2021,51(5):2592
Background/aimThe known pathogenesis of diabetes mellitus (DM) in acromegaly is mainly based on growth hormone (GH) and insulin-like growth factor-1 (IGF-1) excess. Fatty acid-binding protein 4 (FABP-4), a novel adipokine, is found to induce insulin resistance and type 2 DM. We aimed to investigate the possible effect of FABP-4 on glucose metabolism in patients with acromegaly.Materials and methodsThis case-control study included 28 patients newly diagnosed with acromegaly and 57 healthy volunteers. The patients with acromegaly were classified according to their glycemic status as with DM, prediabetes, and normal glucose tolerance. Anthropometric measurements, laboratory test results, and FABP-4 levels of the subjects were evaluated.ResultsAlthough no difference was observed in FABP-4 levels between acromegaly and control groups, the FABP-4 level was higher in the patients with acromegaly having DM compared to the patients with acromegaly having prediabetes and NGT, and the control group (p = 0.004, p = 0.001, p = 0.004, respectively). Logistic regression analysis suggested that the FABP-4 is an independent predictor of DM in acromegaly (β = 7.382, OR = 38.96, 95% CI: 1.52-5.76, p = 0.018).Conclusion The FABP-4 may be a helpful predictor of acromegaly-associated DM. 相似文献
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Background/aimmiRNAs control various biological functions, such as cell proliferation, differentiation, signaling pathways, apoptosis and metabolism. Recently, it has been shown that there is a relationship between changes in miRNA expression and the development of acromegaly. Studies are needed to identify new disease-specific miRNAs. The aim of the current study is to evaluate plasma miR-29c-3p, miR-31-5p and miR-18a-5p steady-state levels in acromegaly. Another aim is to investigate whether there is a difference in the levels of these miRNAs in patients with inadequate control and controlled acromegaly with somatostatin analog (SSA) therapy. These miRNAs targeting the IGF-1 gene were determined by in silico estimation.Materials and methodsThe study included 30 healthy controls (HC) and 20 patients with acromegaly. Anterior pituitary functions and disease activities of patients with acromegaly were evaluated at the time of study. The miR-29c-3p, miR-31-5p and miR-18a-5p levels were measured using quantitative real-time PCR (RT-qPCR).ResultsThe expression level of miR-29c-3p was significantly lower in patients with acromegaly compared to the HC group (p < 0.001). This downregulation was more pronounced in patients with inadequately controlled acromegaly than in patients with acromegaly controlled with somatostatin analogues (SSA) therapy (p = 0.016). Univariate logistic regression analysis results showed that down regulation of miR-29c-3p expression increases the risk of developing acromegaly [OR (95% Cl) = 1.605 (1.142-2.257), p = 0.006]. There was no significant difference between the groups in terms of miR-31-5p and miR-18a-5p expression levels (p = 0.375 and p = 0.649, respectively). ConclusionPlasma miR-29c-3p expression level is downregulated in patients with acromegaly, and this is more pronounced in patients with inadequate control. 相似文献
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NK DEBATA VIMLA VENKATESH RN MISRA YOGESH CHANDER VC OHRI RK SHARMA 《Medical Journal Armed Forces India》1999,55(3):193-196
Seminal fluids of 197 males with complaints of involuntary infertility were examined for spermatozoal counts, morphological changes in the spermatozoa and cultured for ureaplasmas and mycoplasmas. In 12, no spermatozoa were present, 29 had a count of less than one million and 156 had more than one million spermatozoa per mL of the seminal fluid. Various morphological changes were detected in the spermatozoa in some cases. U urealyticum and M hominis were grown in 43.15% and 16.75% in comparison to control figures of 15.9% and 11.4% respectively. There was no correlation between growth of ureaplasmas and the spermatozoal count. Among the morphological changes, presence of coiled tails, presence of a fuzzy coat around the tail and microcolonies were highly specific for culture positivity (98.2, 98.2 and 97.35% respectively) but of low sensitivity (55.2%, 14.1% and 8.2% respectively).KEY WORDS: Mycoplasma, Spermatozoa, Ureaplasma 相似文献
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SK RATH RK SHARMA P TARNEJA AB CHATTOPADHYAY RD WADHWA 《Medical Journal Armed Forces India》2001,57(3):210-212
Ovarian Hyperstimulation Syndrome (OHSS) is a known iatrogenic complication of ovulation induction. Our experience of such complication while managing basic assisted conception cycles has been analysed in the present study. 12 such cases were identified in 976 cycles studied giving an overall incidence of 1.22%. All the cases were of mild to moderate variety and were managed conservatively. The duration of the complication ranged between 10 days to 6 weeks. Polycystic ovarian disease, LH: FSH ratio of more than 1, presence of four or more secondary follicles were found to be important predictive criteria. Identification of predictive factors of OHSS can be helpful in taking due care while using ovulation inducing drugs. Conception does worsen OHSS, but termination is usually not necessary.Key Words: OHSS, Ovulation Induction 相似文献