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21.
Syndecans are among those transmembrane PGs which act via their heparan sulphate chains as receptors for different matrix elements (e.g. collagen I–III, fibronectin, thrombospondin, tenascin) and co-receptors for growth factors (e.g. bFGF, aFGF, GM-CSF, IL-3, IFNg). We hypothesized that there is a positive relationship between the expression of syndecan-1 (CD138) and treatment response in non-Hodgkin’s lymphoma. To identify the expression of syndecan-1 (CD138) in cases of non-Hodgkin’s lymphoma and to correlate its expression with treatment response and disease stage, this study was carried out as a cross-sectional study and included 30 patients with non-Hodgkin’s lymphomas attending Suez Canal University Hospital; diagnosis of patients was made by routine histological and immunohistochemical examination. CD138 mRNA expression was assessed by TaqMan technique using real-time PCR method. There was increased expression of CD138 mRNA in patients with follicular lymphoma than in patients with diffuse large B cell lymphoma (6.25 versus 3.46, respectively) (p?≤?0.05). Syndecan-1 (CD138) mRNA expression from peripheral blood may be a useful marker for follicular lymphoma and can be used as a marker of treatment response in patients with follicular and diffuse large B cell lymphoma.  相似文献   
22.
PurposeThermosensitive in situ gels have been around for decades but only a few have been translated into ophthalmic pharmaceuticals. The aim of this study was to combine the thermo-gelling polymer poloxamer 407 and mucoadhesive polymers chitosan (CS) and methyl cellulose (MC) for developing effective and long-acting ophthalmic delivery systems for L-carnosine (a natural dipeptide drug) for corneal wound healing.MethodsThe effect of different polymer combinations on parameters like gelation time and temperature, rheological properties, texture, spreading coefficients, mucoadhesion, conjunctival irritation potential, in vitro release, and ex vivo permeation were studied. Healing of corneal epithelium ulcers was investigated in a rabbit’s eye model.ResultsBoth gelation time and temperature were significantly dependent on the concentrations of poloxamer 407 and additive polymers (chitosan and methyl cellulose), where it ranged from <10 s to several minutes. Mechanical properties investigated through texture analysis (hardness, adhesiveness, and cohesiveness) were dependent on composition. Promising spreading-ability, mucoadhesion, transcorneal permeation of L-carnosine, high ocular tolerability, and enhanced corneal epithelium wound healing were recorded for poloxamer 407/chitosan systems.ConclusionIn situ gelling systems comprising combinations of poloxamer-chitosan exhibited superior gelation time and temperature, mucoadhesion, and rheological characteristics suitable for effective long-acting drug delivery systems for corneal wounds.  相似文献   
23.
Alopecia areata is a skin disorder characterized by scarless, localized hair loss that is usually managed by topical treatments that might further worsen the condition. Therefore, the current study aimed to develop nano-cubosomes loaded with finasteride (FI) and oregano oil (Or) to improve drug solubility and permeation through skin and then incorporate it into an aloe ferox gel base. An l-optimal coordinate exchange design was adopted to optimize nano-cubosomes. Phytantriol and Alkyl Acrylate were employed as the lipid material, and surfactant respectively for cubosomes manufacture. The produced formulations were assessed for their particle size, entrapment efficiency (EE%), FI steady-state flux (Jss) and minimum inhibitory concentration (MIC) against Pro-pionibacterium acnes. Optimal FI-Or-NCu had a particle size of 135 nm, EE% equals 70%, Jss of 1.85 μg/cm2.h, and MIC of 0.44 μg/ml. The optimum formulation loaded gel gained the highest drug release percent and ex vivo skin permeation compared to FI aqueous suspension, and pure FI loaded gel. Aloe ferox and oregano oil in the optimized gel formulation had a synergistic activity on the FI permeation across the skin and against the growth of p. acne bacteria which could favor their use in treating alopecia. Thus, this investigation affirms the ability of FI-Or-NCu loaded aloe ferox gel could be an effective strategy that would enhance FI release and permeation through skin and maximize its favorable effects in treating alopecia.  相似文献   
24.
The genus Aspergillus is widely distributed in terrestrial and marine environments. In the marine environment, several Aspergillus species have proved their potential to produce a plethora of secondary metabolites including polyketides, sterols, fatty acids, peptides, alkaloids, terpenoids and miscellaneous compounds, displaying a variety of pharmacological activities such as antimicrobial, cytotoxicity, anti-inflammatory and antioxidant activity. From the beginning of 2015 until December 2020, about 361 secondary metabolites were identified from different marine Aspergillus species. In our review, we highlight secondary metabolites from various marine-derived Aspergillus species reported between January 2015 and December 2020 along with their biological potential and structural aspects whenever applicable.

The genus Aspergillus is widely distributed in terrestrial and marine environments.  相似文献   
25.
Tracheoesophageal fistula (TEF) is a bellwether for a country’s ability to care for sick newborns. We aim to review the existing literature from low- and middle-income countries in regard to management of those newborns and the possible approaches to improve their outcomes. A review of the existing English literature was conducted with the aim of assessing challenges faced by providers in LMIC in terms of diagnostic, preoperative, operative and post-operative care for TEF patients. We also review the limited literature for performing thoracoscopic repair in the developing world context and suggest methods for introduction of advanced thoracoscopic procedures including techniques for providing anesthesia to these challenging babies. While outcomes related to technique from LMIC are comparable to the developed world, rates of secondary complications like sepsis and pneumonia are higher. In many areas, repairs are conducted in a staged fashion with minimal utilization of thoracoscopic approach. The paucity of resources creates strain on intraoperative and post-operative management. Clearly, not all developing world contexts are ready to attempt thoracoscopic repair but we outline suggestions for assessing the existing capabilities and a stepwise gradual implementation of advanced thoracoscopy when appropriate.  相似文献   
26.
27.

Thromboembolic complications are the most reported cause of death in coronavirus disease-2019 (COVID-19). Hypercoagulability, platelets activation and endotheliopathy are well-recognized features in COVID-19 patients. The aim of this work was to evaluate circulating soluble selectins P, E and L at the time of hospital admission as predictors for upcoming thrombosis. This retrospective study included 103 hospitalized COVID-19 patients and 50 healthy volunteer controls. COVID-19 patients were categorized into two groups; group 1 who developed thrombosis during hospitalization and group 2 who did not. Soluble selectins were quantitated using ELISA technique. Higher levels of sP-selectin, sE-selectin and sL-selectin were detected in COVID-19 patients compared to controls. Furthermore, significantly higher levels were found in group 1 compared to group 2. Their means were [5.86 ± 1.72 ng/mL vs. 2.51 ± 0.81 ng/mL]; [50 ± 8.57 ng/mL vs. 23.96 ± 6.31 ng/mL] and [4.66 ± 0.83 ng/mL vs. 2.95 ± 0.66 ng/mL] for sP-selectin, sE-selectin and sL-selectin respectively. The elevated selectins correlated with the currently used laboratory biomarkers of disease severity. After adjustment of other factors, sP-selectin, sE-selectin and sL-selectin were independent predictors for thrombosis. At sP-selectin ≥ 3.2 ng/mL, sE-selectin ≥ 32.5 ng/mL and sL-selectin ≥ 3.6 ng/mL thrombosis could be predicted with 97.1%, 97.6% and 96.5% sensitivity. A panel of the three selectins provided 100% clinical sensitivity. Admission levels of circulating soluble selectins P, E and L can predict thrombosis in COVID-19 patients and could be used to identify patients who need prophylactic anticoagulants. E-selectin showed a superior clinical performance, as thrombo-inflammation biomarker, to the most commonly studied P-selectin.

  相似文献   
28.
Several deep‐learning models have been proposed to shorten MRI scan time. Prior deep‐learning models that utilize real‐valued kernels have limited capability to learn rich representations of complex MRI data. In this work, we utilize a complex‐valued convolutional network (?Net ) for fast reconstruction of highly under‐sampled MRI data and evaluate its ability to rapidly reconstruct 3D late gadolinium enhancement (LGE) data. ?Net preserves the complex nature and optimal combination of real and imaginary components of MRI data throughout the reconstruction process by utilizing complex‐valued convolution, novel radial batch normalization, and complex activation function layers in a U‐Net architecture. A prospectively under‐sampled 3D LGE cardiac MRI dataset of 219 patients (17 003 images) at acceleration rates R = 3 through R = 5 was used to evaluate ?Net . The dataset was further retrospectively under‐sampled to a maximum of R = 8 to simulate higher acceleration rates. We created three reconstructions of the 3D LGE dataset using (1) ?Net , (2) a compressed‐sensing‐based low‐dimensional‐structure self‐learning and thresholding algorithm (LOST), and (3) a real‐valued U‐Net (realNet) with the same number of parameters as ?Net . LOST‐reconstructed data were considered the reference for training and evaluation of all models. The reconstructed images were quantitatively evaluated using mean‐squared error (MSE) and the structural similarity index measure (SSIM), and subjectively evaluated by three independent readers. Quantitatively, ?Net ‐reconstructed images had significantly improved MSE and SSIM values compared with realNet (MSE, 0.077 versus 0.091; SSIM, 0.876 versus 0.733, respectively; p < 0.01). Subjective quality assessment showed that ?Net ‐reconstructed image quality was similar to that of compressed sensing and significantly better than that of realNet. ?Net reconstruction was also more than 300 times faster than compressed sensing. Retrospective under‐sampled images demonstrate the potential of ?Net at higher acceleration rates. ?Net enables fast reconstruction of highly accelerated 3D MRI with superior performance to real‐valued networks, and achieves faster reconstruction than compressed sensing.  相似文献   
29.
PROBLEM: To evaluate the association of peripheral leukaemia inhibitory factor (LIF) levels on implantation and miscarriage rates after in vitro fertilization (IVF) treatment. METHODS: Prospective observational study of 120 randomly selected women who underwent IVF treatment. The concentration of LIF in serum was determined by enzyme-linked immunosorbent assay. RESULTS: There was no significant differences with regard to the systemic mean LIF concentration between the pregnant (42 patients, LIF: 11.55 pg/mL +/- 5.3 S.D.) and non-pregnant (66 patients, LIF: 13.47 pg/mL +/- 5.1 S.D.) women after IVF treatment. Likewise, for those women who have positive pregnancy after IVF treatment, the systemic mean LIF levels were not significantly different between women who have an ongoing pregnancy (34 ongoing pregnancy, LIF: 11.26 pg/mL +/- 5.2 S.D.) and those who had miscarriage (eight miscarriage, LIF: 12.78 pg/mL +/- 5.6 S.D.). CONCLUSION: The systemic levels of LIF concentration have no association with implantation rate or miscarriage rate in women undergoing IVF treatment. Measuring serum LIF concentration prior to embryo transfer in IVF treatment has no predictive value of implantation rate or miscarriage rate.  相似文献   
30.
Glycoconjugates represent a recent trend in cancer chemotherapy that adopts the concept of selective prodrug/drug targeting of tumor cells by selectively binding to specific transmembrane glucose transporters. Following preferential uptake of sugar conjugates into cancer cells, they are presumably subject to enzymatic cleavage by specific β-glycosidases to liberate the free active cytotoxic aglycones that act selectively on cancer cells and spare other noncancerous ones. In this sense, the cytotoxicity of an array of newly synthesized glycoconjugates, including curcumin β-glucoside, perillyl alcohol β-glucoside, perillyl alcohol β-galactoside, diethylstilbesterol β-glucoside and diethylstilbesterol β-galactoside have been investigated over 24–96 h in a panel of human colon cancer cells namely, Caco-2, HT29 and T84 cells. The role of β-glycosidases and caspases in the bioactivation and cytotoxicity of these compounds has been addressed in the current study. All the glycoconjugates have proven cytotoxic efficacy in a time-dependent manner. Curcumin β-glucoside was the most potent amongst all glycoconjugates tested. The sensitivity rank order of tumor cells towards all β-glucosides was Caco-2 > HT29 > T84. This sensitivity ranking was well correlated with β-glucosidase activity assessed in these cell lines. Unlike perillyl alcohol galactoside, the cytotoxicity rank order for diethylstilbesterol β-galactoside was not coping with the β-galactosidase activity detected. Apoptosis was assessed by fluorometric assay of caspase-3 and caspase-9 activities. Initiation and activation of apoptosis were increased in all colon cancer cells following exposure to most of the glycoconjugates, and this was well correlated with the cytotoxicity rank order of these prodrugs. Enzymatic cleavage of glycoconjugates was accomplished using a host of hydrolytic enzymes and cleavage kinetics was determined using HPLC. The glycoconjugates were only cleaved by β-glucosidases and β-galactosidases, but not by pancreatic lipase or hepatic esterase. Taken together, one could conclude that β-glucosidases and β-galactosidases are crucial for the bioactivation and cytotoxicity of these glycoconjugates. Also, initiation and activation of apoptosis in tumor cells may contribute, at least partly, for the cytotoxicity of these sugar conjugates.  相似文献   
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