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101.
Zia Zuberi John Silberbauer Francis Murgatroyd 《Indian pacing and electrophysiology journal》2014,14(1):26-31
We describe a patient presenting with incessant ectopic atrial tachycardia during a high risk twin pregnancy. Tachycardia was resistant to escalating doses of beta-blockade with digoxin. Because of increasing left ventricular dysfunction early in the third trimester, catheter ablation was performed successfully at 30 weeks gestation. Electro-anatomic mapping permitted the entire procedure to be conducted without the use of ionizing radiation. The pregnancy proceeded to successful delivery near term and after three years the patient remains recurrence free with normal left ventricular function, off all medication. 相似文献
102.
103.
Khalid Mahmood Zia Mehdi Barikani Ahmad Mukhtar Khalid Hengameh Honarkar 《Carbohydrate polymers》2009,77(3):621-627
Chitin-based polyurethane elastomers (PUEs) constituted on 4,4′-diphenylmethane diisocyanate (MDI), poly(ε-caprolactone) (PCL) and extended with blends of chitin/1,4-butane diol were first synthesized via two step polymerization technique and then irradiated for 50, 100 and 200 h in an UV exposure chamber as such the spectral distribution of the light is good match for terrestrial solar radiation. The surface properties of the irradiated PU samples were investigated by contact angle measurements, surface free energy and water absorption (%), total work of water adhesion to polymer and equilibrium degree of swelling. The effects of UV-irradiation time and chitin contents in chain extenders (CE) proportion on surface properties were investigated. Results of the aforementioned surface techniques revealed that the UV-irradiated polyurethane samples were affected by varying the UV exposure period. 相似文献
104.
Zia U. Khan Suhail Ahmad Ferry Hagen Jack W. Fell Tusharantak Kowshik Rachel Chandy Teun Boekhout 《Antonie van Leeuwenhoek》2010,97(3):253-259
A novel anamorphic Cryptococcus species is described, which was isolated in New Delhi (India) from decaying wood of a tree trunk hollow of Ficus religiosa. On the basis of sequence analysis of the D1/D2 domains of the 26S rRNA gene and the internally transcribed spacer (ITS)-1
and ITS-2 region sequences, the isolate belonged to the Cryptococcus albidus cluster (Filobasidiales, Tremellomycetes) and was closely related to Cryptococcus saitoi, Cryptococcus cerealis and Cryptococcus friedmannii with 98% sequence identity. Phenotypically, the species differed from C. saitoi with respect to growth temperature (up to 37oC), presence of a thin capsule, ability to grow in the absence of vitamins, and inability to assimilate citrate and ethylamine.
With respect to C. friedmannii, it differed in growth temperature, ability to assimilate lactose, raffinose, l-rhamnose, myo-inositol, and inability to utilize citrate. Furthermore, our isolate also differed from C. cerealis in growth temperature, presence of capsule and inability to assimilate l-sorbose. In view of the above phenotypic differences and unique rDNA sequences, we consider that our isolate represents a
new species of Cryptococcus, and therefore, a new species, Cryptococcus randhawai is proposed for this taxon. The type strain J11/2002 has been deposited in the culture collection of the Centraalbureau voor Schimmelcultures (CBS10160)
and CABI Biosciences (IMI 393306). 相似文献
105.
Trichogramma platneri oviposition behavior on Amorbia cuneana egg masses was investigated under laboratory conditions. No relationship was detected between host surface area, number of edge turning on host eggs, and parasitoid clutch size. It was also observed that females parasitized the egg mass randomly by drilling into the egg mass and parasitizing individual eggs without using stereotypical behaviors to assess individual hosts (i.e. drumming and turning). However, clutch size did change due to ovipositional experience as naïve wasps with little or no ovipositional experience (<6 eggs parasitized), allocated significantly more progeny per host than wasps with longer ovipositional experience (24-h oviposition experience on a single egg mass). Moreover, naïve wasps parasitized significantly more eggs on the outer edge of the egg mass than experienced wasps. We contend that the physical characteristics of A. cuneana eggs and egg masses preclude T. platneri from completely discriminating between individual eggs. However, because T. platneri may be using kairomones from the egg mass, this described oviposition strategy remains effective. 相似文献
106.
Jorge R. Paredes‐Montero Muhammad Zia‐Ur‐Rehman Usman Hameed Muhammad Saleem Haider Hans‐Werner Herrmann Judith K. Brown 《Ecology and evolution》2020,10(6):2928-2943
Endosymbionts associated with the whitefly Bemisia tabaci cryptic species are known to contribute to host fitness and environmental adaptation. The genetic diversity and population complexity were investigated for endosymbiont communities of B. tabaci occupying different micro‐environments in Pakistan. Mitotypes of B. tabaci were identified by comparative sequence analysis of the mitochondria cytochrome oxidase I (mtCOI) gene sequence. Whitefly mitotypes belonged to the Asia II‐1, ‐5, and ‐7 mitotypes of the Asia II major clade. The whitefly–endosymbiont communities were characterized based on 16S ribosomal RNA operational taxonomic unit (OTU) assignments, resulting in 43 OTUs. Most of the OTUs occurred in the Asia II‐1 and II‐7 mitotypes (r2 = .9, p < .005), while the Asia II‐5 microbiome was less complex. The microbiome OTU groups were mitotype‐specific, clustering with a basis in phylogeographical distribution and the corresponding ecological niche of their whitefly host, suggesting mitotype‐microbiome co‐adaptation. The primary endosymbiont Portiera was represented by a single, highly homologous OTU (0%–0.67% divergence). Two of six Arsenophonus OTUs were uniquely associated with Asia II‐5 and ‐7, and one occurred exclusively in Asia II‐1, two only in Asia II‐5, and one in both Asia II‐1 and ‐7. Four other secondary endosymbionts, Cardinium, Hemipteriphilus, Rickettsia, and Wolbachia OTUs, were found at ≤29% frequencies. The most prevalent Arsenophonus OTU was found in all three Asia II mitotypes (55% frequency), whereas the same strain of Cardinium and Wolbachia was found in both Asia II‐1 and ‐5, and a single Hemipteriphilus OTU occurred in Asia II‐1 and ‐7. This pattern is indicative of horizontal transfer, suggestive of a proximity between mitotypes sufficient for gene flow at overlapping mitotype ecological niches. 相似文献
107.
Muhammad Abu Bakar Zia Ufuk Demirel Muhammad Azhar Nadeem Mehmet Emin aliskan 《Physiology and Molecular Biology of Plants》2020,26(5):1003-1020
Potato is one of the most important food crops all over the world. Breeding activities for this crop are mainly aimed to improve the quality and yield of tuber. However, genetic architecture of various traits contributing to the quality and yield of potato are not yet completely understood. Genome wide association studies provides a broader way to identify the genomic regions associated with various traits. Panels of 237 tetraploid potato genotypes from different countries were grown for two consecutive years 2016 and 2017 at experimental research area of Potato research center Niğde, Turkey. A genome wide association study using SolCAP 12K array was performed for various morpho-agronomic traits. Structure algorithm and neighborhood joining analysis clearly divided all genotypes into 4 clusters on the basis of their origin. For the marker trait association, Mixed Linear Model in TASSEL was performed and 36 genomic regions were found for the traits under study. The mean r2 value was found to be 0.92 and mean significant LD was 47.5% in the populations. LD patterns reflected the breeding history of potato. The findings of present study provide a framework which could be useful for future potato breeding programs to enhance the production and to reduce the challenges in the coming years to feed world’s population. 相似文献
108.
Rosnani Hanim Mohd Hussain Wan Nur Afiqah Mohamed Kamel Abdul Ghani Naveed Ahmed Khan Ruqaiyyah Siddiqui Tengku Shahrul Anuar 《Saudi Journal of Biological Sciences》2021,28(4):2352-2359
The incidence of Acanthamoeba keratitis has been increasing since the previous decades, especially among contact lens users. This infection is majorly caused by the use of ineffective contact lens disinfecting solution. Thus, this study was conducted to evaluate the in vitro effects of multi-purpose disinfecting solutions (MPDS) against Acanthamoeba trophozoites and cysts. Acanthamoeba genotype T4 isolated from contact lens paraphernalia and an environmental strains were propagated for trophozoite or cyst-containing culture and adjusted in final concentration of 1 × 105 cells/ml. Amoebicidal and cysticidal assays were conducted by incubating trophozoites and cysts with OPTI-FREE® Express®, ReNu® Fresh™, Complete® Multi-Purpose Solution and AVIZOR Unica® Sensitive according to the manufacturer’s minimum recommended disinfectant time (MMRDT) for up to 12 h at 30 ⁰C. Trypan blue hemocytometer-based microscopic counts determined amoebicidal and cysticidal effects. The viability of Acanthamoeba trophozoites and cysts was confirmed by re-inoculated them in the 1.5% non-nutrient agar plates. It was found that none of the MPDS showed amoebicidal and cysticidal effects during the MMRDT. However, OPTI-FREE® Express® demonstrated a significant differences in average cell reduction for both stages within MMRDT. When subjected to 12 h exposure, both OPTI-FREE® Express® and ReNu® Fresh™ led to significant reduction in the number of trophozoite and cyst cells. Notably, Complete® Multi-Purpose Solution and AVIZOR Unica® Sensitive did appreciably improve the solution effectiveness towards trophozoite cells when incubated for 12 h. All MPDS were largely ineffective, with 100% survival of all isolates at MMRDT, while OPTI-FREE® Express® showed limited amoebicidal activity against the contact lens paraphernalia isolate, however, it was more against the environmental strains after 12 h incubation time. The commercially available MPDS employed in this research offered minimal effectiveness against the protozoa despite the contact time. Improvement or development of new solution should consider the adjustment of the appropriate disinfectant concentration, adequate exposure time or the incorporation of novel chemical elements, which are effective against Acanthamoeba for accelerated disinfecting and more reduction of potential exposure of contact lens users to Acanthamoeba keratitis. 相似文献
109.
Zafar Iqbal Sher Ali Jamshed Iqbal Qamar Abbas Irfan Zia Qureshi Shahid Hameed 《Bioorganic & medicinal chemistry letters》2013,23(2):488-491
The desired 3-(arylsulfonyl)spiroimidazolidine-2,4-diones were synthesized by reacting spiroiminoimidazolidine-2,4-dione with arylsulfonyl chlorides. Spiroimidazolidine-2,4-dione was in turn synthesized from norcamphor. Structures of the synthesized molecules were established by modern spectroscopic techniques. The synthesized compounds were screened for in vivo antidiabetic activity and aldose reductase inhibition. Compounds 2a, 2b and 2g exhibited excellent dual activity, compound 2a being most prominent. These results reveal that the synthesized compounds may serve as the molecule of choice to treat diabetes and diabetic complications using a single medication. 相似文献
110.