Synthesis and characterization of tetraphenylporphyrin manganese(III) complexes of phenylcyanamide ligands

Several complexes of TPPMn-L, where TPP is the dianion of tetraphenylporphyrin and L is monoanion of 4-methylphenylcyanamide (4-Mepcyd) (1), 2,4-dimethylphenylcyanamide (2,4-Me₂pcyd) (2), 3,5-dimethylphenylcyanamide (3,5-Me₂pcyd) (3), 4-methoxyphenylcyanamide (4-MeOpcyd) (4), phenylcyanamide (pcyd) (5), 2-chlorophenylcyanamide (2-Clpcyd) (6), 2,5-dichlorophenylcyanamide (2,5-Cl₂pcyd) (7), 2,6-dichlorophenylcyanamide (2,6-Cl₂pcyd) (8), 4-bromophenylcyanamide (4-Brpcyd) (9), and 2,3,4,5-tetrachlorophenylcyanamide (2,3,4,5-Cl₄pcyd) (10), have been prepared from the reaction of TPPMnCl and thallium salt of related phenylcyanamide. Each of the complexes has been characterized by IR, UV-Vis and ¹H NMR spectroscopies.4-Methylphenylcyanamidotetraphenylporphyrin manganese(III) crystallized with one molecule of solvent CHCl₃ in the triclinic crystal system and space group with the following unit cell parameters of: a = 11.596(6) Å; b = 11.768(9) Å; c = 17.81(2) Å; and α, β, γ are 88.91(9)°, 88.16(7)°, 67.90(5)°, respectively; V = 2251(3) Å³; Z = 2. A total of 4234 reflections with I > 2σ(I) were used to refine the structure to R = 0.0680 and R_w = 0.2297. The Mn(III) shows slightly distorted square pyramidal coordination with the 4-methylphenylcyanamide in the axial position, coordinated from nitrile nitrogen. The reduction of each of the TPPMn-L complexes was also examined in dichloromethane and spectroelectrochemical behavior of (1) was investigated and compared to TPPMnCl.     

Hybridization Kinetics Explains CRISPR-Cas Off-Targeting Rules

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Scolicidal Effects of Black Cumin Seed (Nigella sativa) Essential Oil on Hydatid Cysts

Surgery remains the preferred treatment for hydatid cyst (cystic echinococcosis, CE). Various scolicidal agents have been used for inactivation of protoscolices during surgery, but most of them are associated with adverse side effects. The present study aimed to evaluate the in vitro scolicidal effect of Nigella sativa (Ranunculaceae) essential oil and also its active principle, thymoquinone, against protoscolices of hydatid cysts. Protoscolices were aseptically aspirated from sheep livers having hydatid cysts. Various concentrations of the essential oil (0.01-10 mg/ml) and thymoquinone (0.125-1.0 mg/ml) were used for 5 to 60 min. Viability of protoscolices was confirmed by 0.1% eosin staining. Furthermore, the components of the N. sativa essential oil were identified by gas chromatography/mass spectroscopy (GC/MS). Our study revealed that the essential oil of N. sativa at the concentration of 10 mg/ml and its main component, thymoquinone, at the concentration of 1 mg/ml had potent scolicidal activities against protoscolices of Echinococcus granulosus after 10 min exposure. Moreover, thymoquinone (42.4%), p-cymene (14.1%), carvacrol (10.3%), and longifolene (6.1%) were found to be the major components of N. sativa essential oil by GC/MS analysis. The results of this study indicated the potential of N. sativa as a natural source for production of a new scolicidal agent for use in hydatid cyst surgery. However, further studies will be needed to confirm these results by checking the essential oil and its active component in in vivo models.     

Substrate-mediated enhancement of phosphorylated tyrosine hydroxylase in nigrostriatal dopamine neurons: evidence for a role of alpha-synuclein

Tyrosine hydroxylase (TH) protein, phosphorylated at serine-40, serine-31 and serine-19, and enzyme catalytic activity were compared under basal conditions and in activated nigrostriatal dopamine (NSDA) neurons of wild-type and homozygous alpha-synuclein knockout mice. Mice were injected with the D2 antagonist raclopride to stimulate NSDA neuronal activity in the presence or absence of supplemental l-tyrosine. There was no difference in phosphorylated TH levels or TH catalytic activity between wild-type and alpha-synuclein knockout mice under basal conditions or following raclopride-induced acceleration of NSDA activity. In wild-type animals, tyrosine administration potentiated the raclopride-induced increase in phosphorylated TH and enzyme activity. However, tyrosine administration did not enhance phosphorylated TH levels or enzyme catalytic activity in raclopride-stimulated NSDA neurons in alpha-synuclein knockout mice. These findings suggest that alpha-synuclein plays a role in the ability of tyrosine to either enhance TH phosphorylation or hinder TH inactivation during accelerated neuronal activity. The present study supports the hypothesis that alpha-synuclein functions as a molecular chaperone protein that regulates the phosphorylation state of TH in a substrate and activity-dependent manner.     

Control of abscisic acid catabolism and abscisic acid homeostasis is important for reproductive stage stress tolerance in cereals

Drought stress at the reproductive stage causes pollen sterility and grain loss in wheat (Triticum aestivum). Drought stress induces abscisic acid (ABA) biosynthesis genes in anthers and ABA accumulation in spikes of drought-sensitive wheat varieties. In contrast, drought-tolerant wheat accumulates lower ABA levels, which correlates with lower ABA biosynthesis and higher ABA catabolic gene expression (ABA 8'-hydroxylase). Wheat TaABA8'OH1 deletion lines accumulate higher spike ABA levels and are more drought sensitive. ABA treatment of the spike mimics the effect of drought, causing high levels of sterility. ABA treatment represses the anther cell wall invertase gene TaIVR1, and drought-tolerant lines appeared to be more sensitive to the effect of ABA. Drought-induced sterility shows similarity to cold-induced sterility in rice (Oryza sativa). In cold-stressed rice, the rate of ABA accumulation was similar in cold-sensitive and cold-tolerant lines during the first 8 h of cold treatment, but in the tolerant line, ABA catabolism reduced ABA levels between 8 and 16 h of cold treatment. The ABA biosynthesis gene encoding 9-cis-epoxycarotenoid dioxygenase in anthers is mainly expressed in parenchyma cells surrounding the vascular bundle of the anther. Transgenic rice lines expressing the wheat TaABA8'OH1 gene under the control of the OsG6B tapetum-specific promoter resulted in reduced anther ABA levels under cold conditions. The transgenic lines showed that anther sink strength (OsINV4) was maintained under cold conditions and that this correlated with improved cold stress tolerance. Our data indicate that ABA and ABA 8'-hydroxylase play an important role in controlling anther ABA homeostasis and reproductive stage abiotic stress tolerance in cereals.     

Cytokine single nucleotide polymorphisms in Iranian populations

Cytokines are important immunomodulatory molecules involved in immune responses against microorganisms; they also have an important role in the setting of immune system disorders. Cytokine single nucleotide polymorphisms have been extensively studied in different, normal populations as well as in association with disease. Cytokine gene polymorphisms are potentially important as genetic predictors of disease susceptibility, clinical outcome, and as a tool for anthropological studies. In this study, samples have been collected from 455 healthy individuals located in different regions of Iran (Tehran, Yazd, Sistan and Balochistan). Allele and genotype frequencies of cytokine SNP, including: IL-1alpha, IL-1beta, IL-1R, IL-1RA, IL-2, IL-4, IL-4RA, IL-6, IL-10, IL-12, TNF-alpha, TGF-beta and IFN-gamma were investigated, using the PCR-SSP method. Allele frequencies in Tehran and Yazd populations were similar, except for TGF-beta. Allele frequencies in Sistani & Baloch populations were similar at all positions, except for IL-1beta at position of -511 and IFN-gamma genes at position UTR5644; there were some differences in allele frequencies comparing these populations with the Yazd population, including: IL-4, IL-6, IL-10, TGF-beta and TNF-alpha. Although some significant differences were observed for some cytokines, it seems that the cytokine gene polymorphism profile of the Iranian population is similar to that of Caucasians, particularly the Italian population.     

Estimating repeat spectra and genome length from low-coverage genome skims with RESPECT

The cost of sequencing the genome is dropping at a much faster rate compared to assembling and finishing the genome. The use of lightly sampled genomes (genome-skims) could be transformative for genomic ecology, and results using k-mers have shown the advantage of this approach in identification and phylogenetic placement of eukaryotic species. Here, we revisit the basic question of estimating genomic parameters such as genome length, coverage, and repeat structure, focusing specifically on estimating the k-mer repeat spectrum. We show using a mix of theoretical and empirical analysis that there are fundamental limitations to estimating the k-mer spectra due to ill-conditioned systems, and that has implications for other genomic parameters. We get around this problem using a novel constrained optimization approach (Spline Linear Programming), where the constraints are learned empirically. On reads simulated at 1X coverage from 66 genomes, our method, REPeat SPECTra Estimation (RESPECT), had 2.2% error in length estimation compared to 27% error previously achieved. In shotgun sequenced read samples with contaminants, RESPECT length estimates had median error 4%, in contrast to other methods that had median error 80%. Together, the results suggest that low-pass genomic sequencing can yield reliable estimates of the length and repeat content of the genome. The RESPECT software will be publicly available at https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_shahab-2Dsarmashghi_RESPECT.git&d=DwIGAw&c=-35OiAkTchMrZOngvJPOeA&r=ZozViWvD1E8PorCkfwYKYQMVKFoEcqLFm4Tg49XnPcA&m=f-xS8GMHKckknkc7Xpp8FJYw_ltUwz5frOw1a5pJ81EpdTOK8xhbYmrN4ZxniM96&s=717o8hLR1JmHFpRPSWG6xdUQTikyUjicjkipjFsKG4w&e=.