Stimuli-Responsive Nanotherapeutics for Treatment and Diagnosis of Stroke.

Stroke is the second most common medical emergency and constitutes a significant cause of global morbidity. The conventional stroke treatment strategies, including thrombolysis, antiplatelet therapy, endovascular thrombectomy, neuroprotection, neurogenesis, reducing neuroinflammation, oxidative stress, excitotoxicity, hemostatic treatment, do not provide efficient relief to the patients due to lack of appropriate delivery systems, large doses, systemic toxicity. In this context, guiding the nanoparticles toward the ischemic tissues by making them stimuli-responsive can be a turning point in managing stroke. Hence, in this review, we first outline the basics of stroke, including its pathophysiology, factors affecting its development, current treatment therapies, and their limitations. Further, we have discussed stimuli-responsive nanotherapeutics used for diagnosing and treating stroke with challenges ahead for the safe use of nanotherapeutics.

Comparison of Tamoxifen and Clomiphene Citrate for Ovulation Induction in Women with Polycystic Ovarian Syndrome: A Prospective Study.

BACKGROUND: The purpose of this study was to compare the efficacy of tamoxifen and clomiphene citrate in induction of ovulation in women with PCOS and anovulation. METHODS: In this prospective cohort study, 104 women with PCOS and primary infertility were enrolled after fulfilling the inclusion and exclusion criteria. The patients were allocated in two groups; group A (n=54) received tamoxifen 40 mg once daily (Days 3-7) and group B (n=50) received clomiphene citrate 100 mg once daily (Days 3-7). Serial ultrasounds were done till the administration of human chorionic gonadotropin (hCG). The ovulation and pregnancy rates in both groups were compared. The number of dominant follicles, estradiol levels, and endometrial thickness were also studied. Comparison was done using chi-square and student's t-test and a p-value of less than 0.05 was considered statistically significant. RESULTS: The number of dominant follicles and serum estradiol levels were significantly higher in group B (p<0.05), whereas the endometrial thickness was significantly more in group A (p<0.05). The ovulation rates were similar in both groups (66.6% vs. 70%, p=0.715). Pregnancy rate per treatment cycle and per ovulatory cycle was marginally higher in group A (14.81% and 22.22%, respectively), as compared to group B (14% and 20%, respectively), but the difference was not statistically significant (p>0.05). CONCLUSION: Tamoxifen and clomiphene citrate are both equally effective in induction of ovulation and achieving a pregnancy in women with PCOS.

Activated biochar derived from Opuntia ficus-indica for the efficient adsorption of malachite green dye, Cu+2 and Ni+2 from water.

Applicability of biochar in water treatment is gaining interest due to its sustainability and low production cost. Herein, the biochar (BC) and activated biochar (ABC) synthesized from the cladodes of Opuntia ficus-indica (OFI) cactus were evaluated as a renewable adsorbent for adsorption of organic as well as inorganic pollutants including malachite green (MG) dye, Cu+2 and Ni+2 heavy metals. The modification of biochar with NaOH resulted higher surface basicity regarding more oxygen containing functional groups on the surface. The maximum uptake of 1341 mg g-1, 49 mg g-1 and 44 mg g-1 onto activated biochar for malachite green dye, Cu+2 and Ni+2 was acquired through the best fitted Langmuir isotherm model. Pseudo-second-order and Elovich models were found to provide a suitable fit indicating towards the chemisorption of all three components. Film diffusion and chemisorption are the main steps in adsorption of MG dye and heavy metals on activated biochar. The adsorption mechanisms were also hypothesized for adsorption of MG dye, Cu+2 and Ni+2. The remarkable adsorption capacities with higher reusability characteristics for adsorption of organic pollutants as well as inorganic heavy metals entrusts this activated biochar as a potential cost-effective adsorbent to mitigate water pollution issue.

The Formation of a Camalexin Biosynthetic Metabolon.

Arabidopsis (Arabidopsis thaliana) efficiently synthesizes the antifungal phytoalexin camalexin without the apparent release of bioactive intermediates, such as indole-3-acetaldoxime, suggesting that the biosynthetic pathway of this compound is channeled by the formation of an enzyme complex. To identify such protein interactions, we used two independent untargeted coimmunoprecipitation (co-IP) approaches with the biosynthetic enzymes CYP71B15 and CYP71A13 as baits and determined that the camalexin biosynthetic P450 enzymes copurified with these enzymes. These interactions were confirmed by targeted co-IP and Förster resonance energy transfer measurements based on fluorescence lifetime microscopy (FRET-FLIM). Furthermore, the interaction of CYP71A13 and Arabidopsis P450 Reductase1 was observed. We detected increased substrate affinity of CYP79B2 in the presence of CYP71A13, indicating an allosteric interaction. Camalexin biosynthesis involves glutathionylation of the intermediary indole-3-cyanohydrin, which is synthesized by CYP71A12 and especially CYP71A13. FRET-FLIM and co-IP demonstrated that the glutathione transferase GSTU4, which is coexpressed with Trp- and camalexin-specific enzymes, is physically recruited to the complex. Surprisingly, camalexin concentrations were elevated in knockout and reduced in GSTU4-overexpressing plants. This shows that GSTU4 is not directly involved in camalexin biosynthesis but rather plays a role in a competing mechanism.

The Biosynthetic Pathway of Indole-3-Carbaldehyde and Indole-3-Carboxylic Acid Derivatives in Arabidopsis.

Indolic secondary metabolites play an important role in pathogen defense in cruciferous plants. In Arabidopsis (Arabidopsis thaliana), in addition to the characteristic phytoalexin camalexin, derivatives of indole-3-carbaldehyde (ICHO) and indole-3-carboxylic acid (ICOOH) are synthesized from tryptophan via the intermediates indole-3-acetaldoxime and indole-3-acetonitrile. Based on feeding experiments combined with nontargeted metabolite profiling, their composition in nontreated and silver nitrate (AgNO3)-treated leaf tissue was comprehensively analyzed. As major derivatives, glucose conjugates of 5-hydroxyindole-3-carbaldehyde, ICOOH, and 6-hydroxyindole-3-carboxylic acid were identified. Quantification of ICHO and ICOOH derivative pools after glucosidase treatment revealed that, in response to AgNO3 treatment, their total accumulation level was similar to that of camalexin. ARABIDOPSIS ALDEHYDE OXIDASE1 (AAO1), initially discussed to be involved in the biosynthesis of indole-3-acetic acid, and Cytochrome P450 (CYP) 71B6 were found to be transcriptionally coexpressed with camalexin biosynthetic genes. CYP71B6 was expressed in Saccharomyces cerevisiae and shown to efficiently convert indole-3-acetonitrile into ICHO and ICOOH, thereby releasing cyanide. To evaluate the role of both enzymes in the biosynthesis of ICHO and ICOOH derivatives, knockout and overexpression lines for CYP71B6 and AAO1 were established and analyzed for indolic metabolites. The observed metabolic phenotypes suggest that AAO1 functions in the oxidation of ICHO to ICOOH in both nontreated and AgNO3-treated leaves, whereas CYP71B6 is relevant for ICOOH derivative biosynthesis specifically after induction. In summary, a model for the biosynthesis of ICHO and ICOOH derivatives is presented.

Esclerodermia localizada/morfea / Localized scleroderma/morphea

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