Green sonochemical synthesis of BaDy2NiO5/Dy2O3 and BaDy2NiO5/NiO nanocomposites in the presence of core almond as a capping agent and their application as photocatalysts for the removal of organic dyes in water

The present work reports the sonochemical synthesis of DBNO NC (dysprosium nickelate nanocomposite) using metal nitrates and core almond as a capping agent. In addition, the effects of the power of ultrasound irradiation were investigated. The BaDy₂NiO₅/Dy₂O₃ and BaDy₂NiO₅/NiO nanocomposites were synthesized with sonication powers of 50 and 30 W, respectively. The agglomerated nanoparticles were obtained using different sonication powers, including 15, 30, and 50 W. The results showed that upon increasing the sonication power, the particle size decreased. After characterization, the optical, electrical, magnetic, and photocatalytic properties of the NC were studied. The nanocomposites showed an antiferromagnetic behavior. In this study, the photocatalytic degradations of two dyes, AR14 and AB92, were investigated in the presence of DBNO NC. Furthermore, the effects of the amount of photocatalyst, the concentration of the dye solution, the type of organic dye, and light irradiation on the photocatalytic activity of the nanocomposite were studied. The results showed that with an increasing amount of catalyst and decreasing concentration of dye, the photocatalytic activity of the nanocomposite was increased. This activity for the degradation of AR14 is higher than that of AB92. Both AR14 and AB92 dyes show higher photocatalytic degradation under UV irradiation than under Vis irradiation.

The sonochemical synthesis of Dy₂BaNiO₅ nanocomposites is reported, for the first time. The metal nitrates and core almond are used as precursors and capping agent, respectively. Effect of sonication power is investigated in this work.     

Chitosan‐based hydrogels do not induce angiogenesis

The aim of this study was to assess the angiogenic potential of chitosan‐glycerol phosphate (GP)‐hydroxyethyl cellulose (HEC) binder for injectable bone tissue engineering applications. The angiogenic response of chitosan‐GP‐HEC combined with and without human bone marrow‐derived mesenchymal stem cells (hMSCs) was examined using the chick chorioallantoic membrane (CAM) assay. Chitosan‐GP‐HEC gel did not show any angiogenic potential, whereas the presence of hMSCs gave rise to an enhanced angiogenic response when placed on the CAM for 3 days. Quantitatively, significantly more blood vessel formation was observed for the stem cell‐containing group as compared to all other groups (p < 0.05 ), except for the b‐FGF‐positive control. The results indicate that the chitosan‐GP‐HEC binder does not contribute to enhanced angiogenesis and that the presence of hMSCs enhances angiogenesis. Copyright © 2009 John Wiley & Sons, Ltd.     

Antitumor activity of novel pyrrolo[2,3-d]pyrimidin-4-ones

Pyrrolo[2,3-d]pyrimidine is known to have a broad spectrum of biological activities, including antitumor activity. The cytotoxic properties of six novel pyrrolo[2,3-d]pyrimidin-4-ones in vitro were investigated on four different human cancer cell lines. Meanwhile, the role of apoptosis was explored. Malignant cells were cultured in RPMI medium and incubated with different concentrations. Cell viability was quantitated by MTT assay. Apoptotic cells were determined using DAPI (4'-6-diamidino-2-phenylindole) and propidium iodide staining of DNA fragmentation by flow cytometry (sub-G1 peak). We have identified new analogs as a novel class of antiproliferative agents by a cell-based screening method. All compounds inhibited the growth of malignant cells in a dose-dependent manner. The IC?? of compounds 4 and 5 as the two most potent analogs was determined as 122.4 and 106.7 μM in HeLa cells, respectively. Compounds 4 and 5 induced a sub-G1 peak in the flow-cytometry histogram of treated cells, compared to control, indicating that apoptotic cell death is involved in compound 4- and 5-induced toxicity. In conclusion, compounds 4 and 5 exert cytotoxic effects in different cancer cell lines in which apoptosis plays an important role. Thus, compounds 4 and 5 could be considered as potential chemotherapeutic agents.     

New Single Nucleotide Deletion In the SMPD1 Gene Causes Niemann Pick Disease Type A in a Child from Southwest Iran: A Case Report

Objective

Niemann Pick disease (NPD) type A (NPA: MIM #257200) is a lipid storage disorder with an autosomal recessive inheritance and occurrs by defect of the SMPD1 gene encoding sphingomyelinase. Disruption of this enzyme leads to the accumulation of sphingomyelin in brain and liver, which in turn causes dysfunction or damage of tissue.

Methods

We report firstly a 2.5 year old boy with NPA in southwest Iran. Initially, the diagnosis was resulted on the basis of clinical symptoms. The genomic DNA of the suspected individual was subjected to exon sequencing of the SMPD1 gene. According to the human reference sequence {"type":"entrez-nucleotide","attrs":{"text":"NM_000543.4","term_id":"300795568","term_text":"NM_000543.4"}}NM_000543.4, a novel single guanine deletion resulting in a frameshift mutation (p.Gly247Alafs*9) was observed in the SMPD1 gene that might be causative for the outcome of the disease.

Findings

The present report is the first molecular genetics diagnosis of the NPA in southwest Iran. The detected deletion in the SMPD1 gene is remarkable because of its novelty.

Conclusion

Despite similar morbidity SGA infants exhibited higher lethal complication rates following delayed meconium passage compared to AGA infants.     

Biocompatibility and gelation of chitosan-glycerol phosphate hydrogels

The aim of this study was to evaluate the cytotoxicity and gelation of thermosensitive chitosan-beta-glycerol phosphate (GP) solutions, which undergo sol-gel transition around body temperature. Chitosan 0.5-2% (w/v) mixed with GP 5-20% (w/v) solutions all gel at 37 degrees C and possess pH around the physiological range. High GP and chitosan concentrations result in faster gelation time. Extracts of all chitosan concentrations mixed with or without 5% (w/v) GP and 2% (w/v) chitosan combined with 10% (w/v) GP demonstrated up to 34% increase in proliferation rate of goat bone marrow derived mesenchymal stem cells when compared with control medium. Extracts from all other chitosan-GP combinations resulted in reduced cell proliferation relative to control medium. Increasing GP content in the gel resulted in a linear increase in the osmolality of the extracts in contact with the gels. The results of this study indicate that chitosan-GP is a biocompatible hydrogel, extracts of which can stimulate mesenchymal stem cell proliferation at certain concentrations. This material is therefore a promising vehicle for cell encapsulation and injectable tissue-engineering applications.     

Cow's Milk Anaphylaxis in Children First Report of Iranian Food Allergy Registry

Cow's milk anaphylaxis is the most common food-induced anaphylaxis in Iranian children. The clinical and laboratory findings of cow's milk anaphylaxis are evaluated in this study. All children who had experienced cow's milk anaphylaxis and had been referred to Immunology, asthma and allergy research center during a 5-year period were considered. After fulfilling a questionnaire, patients underwent measurement of total IgE and cow's milk-specific IgE by Immunocap test and Skin prick test (SPT) with cow's milk extract. Patients with a convincing history and one positive cow's milk-specific IgE test (SPT or Immunocap test) and patients with both positive tests were enrolled, in this study.Out of 49 patients, 59.2% were male. Patients' mean age was 5 years old and their mean age at the time of first attack was 5.7 months (SD = 4.3). Most of the patients have experienced more than one episode of anaphylaxis (79.5%) and in 85.7% of all cases, first attack occurred during the first year of life. Severity grading 1-5 were 2%, 6.1%, 18.4%, 69.4%, 4.1% respectively. Most common manifestations were cutaneous 98%, Respiratory 91.8%, Gastrointestinal 55.1%, Cardiovascular 46.9% and neurologic 46.9% signs and symptoms respectively. Twenty four patients showed positive SPT. Mean total IgE was 239.6±3.3 (IU/mL) and mean cow's milk-specific IgE was 19.28±27.2 (IU/mL). Most patients showed reactions only after ingestion of cow's milk or after dairy foods (81.6%).It is concluded that cow's milk anaphylaxis may happen early in life. Regarding the severity of attacks and remarkable number of patients with several attacks, poor knowledge about this disorder is evident.     

Role of gap junctional coupling in astrocytic networks in the determination of global ischaemia-induced oxidative stress and hippocampal damage

While there is evidence that gap junctions play important roles in the determination of cell injuries, there is not much known about mechanisms by which gap junctional communication may exert these functions. Using a global model of transient ischaemia in rats, we found that pretreatment with the gap junctional blockers carbenoxolone, 18alpha-glycyrrhetinic acid and endothelin, applied via cannulae implanted into the hippocampus in one hemisphere, resulted in decreased numbers of TUNEL-positive neurons, as compared with the contralateral hippocampus that received saline injection. Post-treatment with carbenoxolone for up to 30 min after the stroke injury still resulted in decreased cell death, but post-treatment at 90 min after the ischaemic insult did not result in differences in cell death. However, quinine, an inhibitor of Cx36-mediated gap junctional coupling, did not result in appreciable neuroprotection. Searching for a possible mechanism for the observed protective effects, possible actions of the gap junctional blockers in the electrical activity of the hippocampus during the ischaemic insult were assessed using intracerebral recordings, with no differences observed between the saline-injected and the contralateral drug-injected hippocampus. However, a significant reduction in lipid peroxides, a measure of free radical formation, in the hippocampus treated with carbenoxolone, revealed that the actions of gap junctional coupling during injuries may be causally related to oxidative stress. These observations suggest that coupling in glial networks may be functionally important in determining neuronal vulnerability to oxidative injuries.     

The effect of chronic administration of l-arginine on the learning and memory of estradiol-treated ovariectomized rats tested in the morris water maze

OBJECTIVE:

The present study was carried out to evaluate the effect of l-arginine on the learning and memory of estradiol-treated ovariectomized (OVX) rats.

METHODS:

Forty-eight rats were divided into six groups: (1) sham, (2) OVX, (3) sham-Est, (4) OVX-Est, (5) sham-Est-LA, and (6) OVX-Est-LA. The animals of the sham-Est and OVX-Est groups were treated by weekly injection of estradiol valerate (2mg/kg). The sham-Est-LA and OVX-Est-LA groups were treated in the same manner but with an additional daily injection of l-arginine (200mg/kg). After eight weeks, animals of all groups were tested in the Morris water maze. The escape latency and path traveled to reach the platform were compared between groups.

RESULTS:

Time latency and path length in the OVX group were significantly higher than in the sham group (P<0.05). The OVX-Est group had a significantly shorter traveled path length and time latency compared to the OVX group (P<0.001). Time latency and path length in the sham-Est group was significantly higher than in the sham group (P<0.001). Time latency and path length in the OVX-Est-LA group were significantly higher than in the OVX-Est group.

CONCLUSIONS:

These results allow us to propose that chronic treatment with estradiol enhances the spatial learning and memory of OVX rats, and that long term l-arginine treatment attenuates the effects of improvement produced by estradiol in OVX rats.