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  1. Article: Early Development of Direct Embryos in the Cultured Anthers of

    Dissanayake, Lakmali / Perera, Prasanthi / Attanayaka, Thilak / Heberle, Erwin / Jayawardhana, Manosha

    Plants (Basel, Switzerland)

    2020  Volume 9, Issue 10

    Abstract: Cassava is one of the most important sources of energy. To meet the growing demand, genetic improvement is of utmost importance. Its cross-pollinating nature limits the opportunity of exploitation of hybrid vigor and demands the development of homozygous ...

    Abstract Cassava is one of the most important sources of energy. To meet the growing demand, genetic improvement is of utmost importance. Its cross-pollinating nature limits the opportunity of exploitation of hybrid vigor and demands the development of homozygous lines through doubled-haploid technologies. The problems in callus-mediated embryogenesis, such as longer processing time and genetically unstable nature, can be overcome by direct embryogenesis. Conditions to produce embryos directly from microspores in cultured anthers were optimized. The optimum stress pretreatment condition was 40 °C for 6 h after culturing the anthers into the induction medium. For proembryo formation, 2% sucrose and 5 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) or 1 mg/l 1-naphthaleneacetic acid were optimum. Globular embryos were formed by subculturing proembryos into the medium with 0.5 mg/l 2,4-D and 5 mg/l 6-benzylaminopurine after two weeks of culturing. Light microscopy of cultured anthers demonstrated the formation of multicellular structures and their further development into proembryos. Microscopic studies showed proembryos emerging through the damaged anther wall. Monoallelic banding in simple sequence repeat (SSR) analysis indicated homozygous or haploid states in some of the originated embryos. The conditions optimized in this study were effective in the early development of direct embryos after two weeks of culture initiation. This is the first report of the formation of direct embryos in cultured anthers of cassava.
    Language English
    Publishing date 2020-10-06
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2704341-1
    ISSN 2223-7747
    ISSN 2223-7747
    DOI 10.3390/plants9101315
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Early Development of Direct Embryos in the Cultured Anthers of Manihot esculenta Crantz

    Dissanayake, Lakmali / Perera, Prasanthi / Attanayaka, Thilak / Heberle, Erwin / Jayawardhana, Manosha

    Plants. 2020 Oct. 06, v. 9, no. 10

    2020  

    Abstract: Cassava is one of the most important sources of energy. To meet the growing demand, genetic improvement is of utmost importance. Its cross-pollinating nature limits the opportunity of exploitation of hybrid vigor and demands the development of homozygous ...

    Abstract Cassava is one of the most important sources of energy. To meet the growing demand, genetic improvement is of utmost importance. Its cross-pollinating nature limits the opportunity of exploitation of hybrid vigor and demands the development of homozygous lines through doubled-haploid technologies. The problems in callus-mediated embryogenesis, such as longer processing time and genetically unstable nature, can be overcome by direct embryogenesis. Conditions to produce embryos directly from microspores in cultured anthers were optimized. The optimum stress pretreatment condition was 40 °C for 6 h after culturing the anthers into the induction medium. For proembryo formation, 2% sucrose and 5 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) or 1 mg/l 1-naphthaleneacetic acid were optimum. Globular embryos were formed by subculturing proembryos into the medium with 0.5 mg/l 2,4-D and 5 mg/l 6-benzylaminopurine after two weeks of culturing. Light microscopy of cultured anthers demonstrated the formation of multicellular structures and their further development into proembryos. Microscopic studies showed proembryos emerging through the damaged anther wall. Monoallelic banding in simple sequence repeat (SSR) analysis indicated homozygous or haploid states in some of the originated embryos. The conditions optimized in this study were effective in the early development of direct embryos after two weeks of culture initiation. This is the first report of the formation of direct embryos in cultured anthers of cassava.
    Keywords 2,4-D ; Manihot esculenta ; anthers ; benzyladenine ; cassava ; doubled haploids ; early development ; embryogenesis ; energy ; genetic improvement ; genetic instability ; haploidy ; heterosis ; homozygosity ; light microscopy ; microsatellite repeats ; microspores ; naphthaleneacetic acid ; processing time ; sucrose
    Language English
    Dates of publication 2020-1006
    Publishing place Multidisciplinary Digital Publishing Institute
    Document type Article
    ZDB-ID 2704341-1
    ISSN 2223-7747
    ISSN 2223-7747
    DOI 10.3390/plants9101315
    Database NAL-Catalogue (AGRICOLA)

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  3. Book ; Online: An Initial Access Optimization Algorithm for millimeter Wave 5G NR Networks

    Perera, A. Indika / Manosha, K. B. Shashika / Rajatheva, Nandana / Latva-aho, Matti

    2019  

    Abstract: The millimeter wave (mmWave) communication uses directional antennas. Hence, achieving fine alignment of transmit and receive beams at the initial access phase is quite challenging and time-consuming. In this paper, we provide a dynamic-weight based beam ...

    Abstract The millimeter wave (mmWave) communication uses directional antennas. Hence, achieving fine alignment of transmit and receive beams at the initial access phase is quite challenging and time-consuming. In this paper, we provide a dynamic-weight based beam sweeping direction and synchronization signal block (SSB) allocation algorithm to optimize the cell search of the initial access in mmWave 5G NR networks. The number of SSBs transmitted in each beam sweeping direction depends on previously learned experience which is based on the number of detected UEs (user equipment) per SSB for each sweeping direction. Overall, numerical simulation results indicate that the proposed algorithm is shown to be capable of detecting more users with a lower misdetection probability. Furthermore, it is possible to achieve the same performance with a smaller number of dynamic resource (i.e., SSB) allocation, compared to constant resource allocation.

    Comment: Submitted ICC 2020
    Keywords Electrical Engineering and Systems Science - Signal Processing
    Publishing date 2019-10-31
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: Prevalence of Bacillus cereus and associated risk factors in Chinese-style fried rice available in the city of Colombo, Sri Lanka.

    Perera, Manosha Lakmali / Ranasinghe, Gerard Ranjan

    Foodborne pathogens and disease

    2012  Volume 9, Issue 2, Page(s) 125–131

    Abstract: The present study aimed to assess the prevalence of Bacillus cereus and its associated risk factors in Chinese-style fried rice available in Colombo city. In 200 samples of fried rice the prevalence of B. cereus was 56%. The prevalence by variety of ... ...

    Abstract The present study aimed to assess the prevalence of Bacillus cereus and its associated risk factors in Chinese-style fried rice available in Colombo city. In 200 samples of fried rice the prevalence of B. cereus was 56%. The prevalence by variety of fried rice was chicken (20.0%), vegetable (18.0%), seafood (10.0%), egg (5.0%), mixed (2.0%), and beef (1.0%). Of analyzed samples, 28 (14%) had colony counts >10(6) colony forming units per gram (cfu/g), the infectious dose for B. cereus food borne outbreaks. Occurrence of >10(6) cfu/g of B. cereus were associated with storage of boiled rice at room temperature (p=0.030), >4 hours of storage at room temperature (p=0.042) and cooking frequency of more than once per dining session (p=0.017). The type of rice and the quantity boiled per day were not independent risk factors for high B. cereus counts. Majority of B. cereus isolates (53.7%) in this study were not typable. The serotypes observed included H15 (14.3%), H19 (14.3%), and H20 (10.7%). These serotypes are known to be associated with both emetic and diarrheal syndromes. All isolates were sensitive to ciprofloxacin (100%), erythromycin (100%), gentamicin (100%), chloramphenicol (100%), and amikacin (100%) whereas 100% resistance was observed for penicillin with minimal inhibitory concentration range of 32-256 μg/mL.
    MeSH term(s) Animals ; Anti-Bacterial Agents/pharmacology ; Asian Continental Ancestry Group ; Bacillus cereus/drug effects ; Bacillus cereus/growth & development ; Bacillus cereus/isolation & purification ; Cattle ; Chickens/microbiology ; Colony Count, Microbial ; Food Contamination/analysis ; Food Handling/methods ; Food Microbiology ; Humans ; Meat/microbiology ; Oryza/microbiology ; Ovum/microbiology ; Prevalence ; Risk Factors ; Seafood/microbiology ; Spores, Bacterial ; Sri Lanka/epidemiology ; Temperature ; Time Factors ; Vegetables/microbiology
    Chemical Substances Anti-Bacterial Agents
    Language English
    Publishing date 2012-02
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2148479-X
    ISSN 1556-7125 ; 1535-3141
    ISSN (online) 1556-7125
    ISSN 1535-3141
    DOI 10.1089/fpd.2011.0969
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: A dysbiotic mycobiome dominated by

    Perera, Manosha / Al-Hebshi, Nezar Noor / Perera, Irosha / Ipe, Deepak / Ulett, Glen C / Speicher, David J / Chen, Tsute / Johnson, Newell W

    Journal of oral microbiology

    2017  Volume 9, Issue 1, Page(s) 1385369

    Abstract: The aim of this study was to characterize the mycobiome associated with oral squamous-cell carcinoma (OSCC). DNA was extracted from 52 tissue biopsies (cases: 25 OSCC; controls: 27 intra-oral fibro-epithelial polyps [FEP]) and sequenced for the fungal ... ...

    Abstract The aim of this study was to characterize the mycobiome associated with oral squamous-cell carcinoma (OSCC). DNA was extracted from 52 tissue biopsies (cases: 25 OSCC; controls: 27 intra-oral fibro-epithelial polyps [FEP]) and sequenced for the fungal internal transcribed spacer 2 region using Illumina™ 2 x300bp chemistry. Merged reads were classified to species level using a BLASTN-algorithm with UNITE's named species sequences as reference. Downstream analyses were performed using QIIME™ and linear discriminant analysis effect size. A total of 364 species representing 160 genera and two phyla (Ascomycota and Basidiomycota) were identified, with
    Language English
    Publishing date 2017-10-27
    Publishing country United States
    Document type Journal Article
    ISSN 2000-2297
    ISSN 2000-2297
    DOI 10.1080/20002297.2017.1385369
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Emerging role of bacteria in oral carcinogenesis: a review with special reference to perio-pathogenic bacteria.

    Perera, Manosha / Al-Hebshi, Nezar Noor / Speicher, David J / Perera, Irosha / Johnson, Newell W

    Journal of oral microbiology

    2016  Volume 8, Page(s) 32762

    Abstract: Oral cancer, primarily oral squamous cell carcinoma (OSCC), continues to be a major global health problem with high incidence and low survival rates. While the major risk factors for this malignancy, mostly lifestyle related, have been identified, around ...

    Abstract Oral cancer, primarily oral squamous cell carcinoma (OSCC), continues to be a major global health problem with high incidence and low survival rates. While the major risk factors for this malignancy, mostly lifestyle related, have been identified, around 15% of oral cancer cases remain unexplained. In light of evidence implicating bacteria in the aetiology of some cancer types, several epidemiological studies have been conducted in the last decade, employing methodologies ranging from traditional culture techniques to 16S rRNA metagenomics, to assess the possible role of bacteria in OSCC. While these studies have demonstrated differences in microbial composition between cancerous and healthy tissues, they have failed to agree on specific bacteria or patterns of oral microbial dysbiosis to implicate in OSCC. On the contrary, some oral taxa, particularly Porphyromonas gingivalis and Fusobacterium nucleatum, show strong oral carcinogenic potential in vitro and in animal studies. Bacteria are thought to contribute to oral carcinogenesis via inhibition of apoptosis, activation of cell proliferation, promotion of cellular invasion, induction of chronic inflammation, and production of carcinogens. This narrative review provides a critical analysis of and an update on the association between bacteria and oral carcinogenesis and the possible mechanisms underlying it.
    Language English
    Publishing date 2016-09-26
    Publishing country United States
    Document type Journal Article ; Review
    ISSN 2000-2297
    ISSN 2000-2297
    DOI 10.3402/jom.v8.32762
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Emerging role of bacteria in oral carcinogenesis

    Manosha Perera / Nezar Noor Al-hebshi / David J. Speicher / Irosha Perera / Newell W. Johnson

    Journal of Oral Microbiology, Vol 8, Iss 0, Pp 1-

    a review with special reference to perio-pathogenic bacteria

    2016  Volume 10

    Abstract: Oral cancer, primarily oral squamous cell carcinoma (OSCC), continues to be a major global health problem with high incidence and low survival rates. While the major risk factors for this malignancy, mostly lifestyle related, have been identified, around ...

    Abstract Oral cancer, primarily oral squamous cell carcinoma (OSCC), continues to be a major global health problem with high incidence and low survival rates. While the major risk factors for this malignancy, mostly lifestyle related, have been identified, around 15% of oral cancer cases remain unexplained. In light of evidence implicating bacteria in the aetiology of some cancer types, several epidemiological studies have been conducted in the last decade, employing methodologies ranging from traditional culture techniques to 16S rRNA metagenomics, to assess the possible role of bacteria in OSCC. While these studies have demonstrated differences in microbial composition between cancerous and healthy tissues, they have failed to agree on specific bacteria or patterns of oral microbial dysbiosis to implicate in OSCC. On the contrary, some oral taxa, particularly Porphyromonas gingivalis and Fusobacterium nucleatum, show strong oral carcinogenic potential in vitro and in animal studies. Bacteria are thought to contribute to oral carcinogenesis via inhibition of apoptosis, activation of cell proliferation, promotion of cellular invasion, induction of chronic inflammation, and production of carcinogens. This narrative review provides a critical analysis of and an update on the association between bacteria and oral carcinogenesis and the possible mechanisms underlying it.
    Keywords bacteria ; carcinoma ; dysbiosis ; inflammation ; microbiome ; mouth ; squamous cell ; Microbiology ; QR1-502 ; Science ; Q ; Infectious and parasitic diseases ; RC109-216
    Subject code 610
    Language English
    Publishing date 2016-09-01T00:00:00Z
    Publisher Taylor & Francis Group
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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