MOSP - Macao Scientific Publishers

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Growth response of Pterocarpus soyauxii and Lophira alata seedlings to host soil mycorrhizal inocula in relation to land use types

N. A. Onguene*, L. E. M. Ngonkeu and T. W. Kuyper

Abstract: Deficiency in mycorrhizal inoculum in soils due to land use types (LUT) can be alleviated by quantity and quality inoculum addition. A bioassay was carried out to determine how host soil mycorrhizal inoculum influenced mycorrhizal colonization, carbon allocation and partitioning of seedlings of two native timber species of Cameroon humid forest. Seedlings of Pterocarpus soyauxii and Lophira alata were raised for six months on surface soils (0 - 20 cm) collected from early secondary forests and LUT derived from slash-and-burn agriculture and selective logging. Mycorrhizal inoculation effect (MIE) was derived. Seedlings were mainly colonized by members of the Glomaceae and Gigasporaceae, respectively, as shown by molecular typing. They generally performed poorly in soils with indigenous inoculum. But addition of soil inoculum from P. soyauxii trees favored nodulation, significantly increased mycorrhizal colonization and total biomass but decreased root-to-shoot ratios, resulting in large and positive MIE, irrespective of LUT. ln contrast, host soil inoculum of L. alata did not affect fractional mycorrhizal colonization but significantly increased total biomass and resulted in high carbon allocation to roots in low and sometimes negative MIE. Therefore, seedlings' responses to mycorrhizal inoculum depend on host soil inoculum and that could be critical for successful rejuvenation of tropical trees.[...] Read More.

Keywords: Arbuscular, mycorrhiza-host, soil, inoculum-Iand use types, Pterocarpus soyauxii, Lophira alata, Cameroon.

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Detection of the anaerobic bacteria in the odontogenic cyst fluids using polymerase chain reaction (PCR) method

Fahriye Keskin, Sevgi Ciftci, Sirmahan Cakarer, Firat Selvi, Taylan Can, Sevda Ozel and Cengizhan Keskin

Abstract: Odontogenic cysts are slow growing lesions which are formed by epithelium. They may reach to a substantial size without symptoms for a long time. Radicular cysts’ (RCs) and odontogenic keratocysts’ (OKCs) are common odontogenic cysts of jaws. The main purpose of this study is to evaluate if anaerobic bacteria play a role in the pathogenesis of the RCs and OKCs fluids by polymerase chain reaction (PCR). Odontogenic cyst fluid samples with a history of infection were collected from a total of 28 odontogenic cysts consisting of 16 samples of OKCs and 12 samples of RCs. Anaerobic bacteria detection were performed by PCR based on bacterial 16S rRNA genes. Porphyromonas gingivalis existed more frequently compared to the other bacteria, in all samples (39.2%). Following this, F. nucleatum (32.1%), Provetella intermedia and Campylobacter rectus ( 25.5%), Treponema denticola (25%), Provetella nigrescens and Tannerella forsythia (17.8%), Dialister pneumosintes (14.2%), Filifactor alocis (10.7%), Porphyromonas endodontalis and Provetella pallens (7.1%) were seen. The 58.3% of the Fusobacterium nucleatum positive cyst fluids were in the RCs group. In D. pneumosintes positive cysts liquid samples, C. rectus was found to be positive (p=0.025). The same correlation was observed between F. alocis and C. rectus (p= 0.003). On the other hand, in F. alocis positive cysts liquid samples, F. nucleatum also was found to be positive (p=0.026). Odontogenic cysts fluid contained numerous anaerobic bacteria of various types, thus suggesting that oral bacteria may cause symptoms in odontogenic cyst fluids. Further studies are needed to assess the role of these bacteria in the pathogenesis of odontogenic cysts.[...] Read More.

Keywords: Polymerase chain reaction (PCR), odontogenic cyst, anaerobic bacteria.

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Prevalence study of cytomegalovirus (CMV) infection among foreign manpower in Jeddah Saudi Arabia

N. A. Redwan, M. M. M. Ahmed,* and M. S. H. AL Awfi

Abstract: Human cytomegalovirus (HCMV) is a species-specific DNA virus of the Herpetoviridae family. Cytomegalovirus (CMV) is more widespread in developing countries and in areas of low socio-economic conditions. It causes high morbidity and mortality. After primary infection CMV is not eradicated but establishes life-long infection in its host. CMV dispersed and become dormant or latent in multiple end organs, and can later be reactivated by a number of different stimuli, including immunosuppresion and inflammation. To determine CMV prevalence in a sample of the foreign manpower population in Jeddah region, Saudi Arabia, we tested serum samples for CMV-specific immunoglobulin G from participants aged 20 to 60 years (n = 514) by enzyme linked immunosorbent assay (ELISA). The prevalence of CMV infection was 80.7% in studied population. CMV prevalence differed significantly by sex (p[...] Read More.

Keywords: Cytomegalovirus (CMV), virus, seroprevalence, enzyme linked immunosorbent assay (ELISA), immunoglobulin G (IgG).

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An investigation on the pollen germination and tube growth in some Prunus persica genotypes and cultivars

Yavar Sharafi

Abstract: Peaches and nectarines (Prunus persica) are stone fruit trees which their pistils needed to be pollinated and fertilized to set fruits therefore; pollen characteristics including pollen viability, longevity, morphological homogeneity, germination and pollen tube growth rate are very important component of fertilization and fruit setting. However, study of main pollen traits is one of the most important approaches for growers and breeders. In this research, main pollen characteristics including germination, tube growth and longevity were investigated in some favorable selected genotypes and cultivars of peach and nectarine. Pollen traits of 5 genotypes and 10 cultivars were studied after two month maintenance in - 20°C using the in vitro medium containing 14% sucrose and 1.2% agar. Results shows that in all of the studied characteristics, significant differences were observed among cultivars and genotypes. However, genotypes and cultivars with good quantitative and qualitative pollen traits were selected for peach and nectarine orchard establishment and breeding programs in Iran.[...] Read More.

Keywords: Peach, nectarine, pollen germination, pollen tube growth, viability, in vitro.

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Medium formulation and impeller design on the biosynthesis of high molecular weight hyaluronic acid by Streptococcus zooepidemicus ATCC 39920

Zee-Wei Lai, Raha Abdul Rahim, Arbakariya Ariff, and Rosfarizan Mohamad, *

Abstract: The effects of medium formulation and impeller design (Rushton turbine and helical ribbon) on hyaluronic acid (HA) biosynthesis by Streptococcus zooepidemicus ATCC 39920 were investigated using a 2 L stirred-tank bioreactor. The effect of different glucose concentrations (20, 30, 50 and 60 g/L), nitrogen sources ((NH4)2S2O8, (NH4)2PO 4, yeast extract, and tryptone) and carbon/nitrogen ratios on the growth of the strain and on HA biosynthesis were initially investigated. Organic nitrogen sources (yeast extract and tryptone) were proven to be favourable in media for HA biosynthesis compared to inorganic nitrogen sources. About 2.442 g/L of HA with a high molecular weight (4.36 x 106 Da) was synthesised at an optimal C/N of 2.5:1 (using a mixture of yeast extract and tryptone) in a 2 L stirred-tank bioreactor equipped with a Rushton turbine impeller. When using an optimal medium formulation at equal HA production levels, the helical ribbon impeller resulted in a higher molecular weight of HA (5.20 x 106 Da) compared to the Rushton turbine impeller.[...] Read More.

Keywords: Streptococcus spp., hyaluronic acid, helical ribbon impeller, carbon/nitrogen.

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Genotyping of Hepatitis C virus (HCV) in infected patients from Saudi Arabia

Mohammed Ali M. Marie

Abstract: A molecular study was carried to investigate the prevalence of Hepatitis C virus (HCV) genotypes in HCV infected population of Saudi Arabia. A total of HCV-positive clinical specimens (serum, EDTA plasma) with viral loads above 2,000 IU/ml were collected for genotyping. Genotyping of 358 samples revealed four different genotypes including 1 (1a and 1b), 2a, 3 (3a) and 4. The most prevalent genotype was 4 with rate of 74.2% followed by genotype 3 (11.7%) and 1a (3.9%). The predominance of HCV genotype 4 in our population confirms the predominance of HCV genotype 4 in Saudi Arabia and most of the Arab countries in the Middle East.[...] Read More.

Keywords: Hepatitis C virus (HCV), genotypes, Saudi Arabia, Riyadh.

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Virulence and characteristics of a new nucleopolyhedrovirus strain of Dendrolimus kikuchii (Lepidoptera: Lasiocampidae)

Miao Miao Yang, Meng Lou Li, Yu Zhu Wang, Liang Jian Qu, Ke Yue Huai, Xue Wen Nie, Lu Qin Qiao, Jin Ying Ding and Yong An Zhang*

Abstract: In present study, a nucleopolyhedrovirus was isolated from the infected larvae of Dendrolimus kikuchii, which is a serious pest for a variety of conifers in China. Ultrastructural observation revealed that this virus is a multiple-nucleocapsid nucleopolyhedrovirus (MNPV), which was encapsulated within the envelope of each virion. Based on the morphological characteristics, it was identified as a new virus and named as DkNPV. It exhibited high potential as a biocontrol agent to protect the forest because of the high virulence against the third-instar larvae of D. kikuchii. The virus passage in the host after 4 generations, toxicity and ultrastructural morphology were stable.[...] Read More.

Keywords: Dendrolimus kikuchii, multiple-nucleocapsid nucleopolyhedrovirus, Dendrolimus Kikuchii Matsumura nuclear polyhedrosis virus (DkNPV), virulence, ultrastructure, biological control.

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Pulmonary tuberculosis associated with increased number and percentage of natural killer and B cells in the peripheral blood

Adel Almogren

Abstract: Host defense against Mycobacterium tuberculosis (MTB) is essentially a cell mediated immune response. The aim of this study is to assess immune abnormalities in the peripheral blood lymphocyte subsets in patients with pulmonary tuberculosis. Flowcytometry data for peripheral blood lymphocyte subsets in ten patients (mean age of 27 ± 6 years) with pulmonary tuberculosis were compared with similar data from 25 normal healthy individuals (mean age 24 ± 6 years) retrospectively in Immunology Unit at King Khalid University Hospital, Riyadh. The absolute numbers (523.7 ± 360.9 vs 177.1 ± 133.7, p = 0.0000) and % (28 ± 12.8% vs 9.9 ± 5.6%, p = 0.0000) of the natural killer cells and B lymphocytes (426.8 ± 452.1 vs 205.7 ± 69 p = 0.0000 and 18.2 ± 8.1% vs 11 ± 2.5%, p = 0.0000, respectively) were significantly higher in patients with PTB than the normal healthy individuals. A marked reduction in the absolute numbers (542.9 ± 350.3 vs 775.7 ± 225.4, p = 0.0250) and the percentage (30.8 ± 10.7% vs 44.01 ± 5.4%, p = 0.0000) of CD4 + cells in patients with pulmonary tuberculosis was also noted. Elevated natural killer and B cells with CD4 + lymphopenia in pulmonary tuberculosis prompt further investigations to gain a better understanding of host defense against M. tuberculosis.[...] Read More.

Keywords: Mycobacterium tuberculosis, natural killer cells, lymphocyte subsets, pulmonary tuberculosis.

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Interaction of severe acute respiratory syndrome (SARS) nucleocapsid protein with macrophage migration inhibitory factor protein (MIF)

Yang Lin,*, Baohua Wang*, Yijun Liu, Zhigang Yu, Manhua Cui and Haichun Ma

Abstract: The nucleocapsid (N) protein of SARS coronavirus (SARS-CoV) is a major structural component of virions, which appears to be a multifunctional protein involved in viral RNA replication and translation. However, how N protein interacts with host protein remains largely elusive. To identify cellular proteins that interact with the N protein and to elucidate the possible involvement of N protein in SARS-Cov replication and translation, a human lung cDNA library was screened using a yeast two-hybrid system assay. In this study, we have identified Macrophage migration inhibitory factor protein (MIF) as a novel interaction partner of N protein by yeast two-hybrid system. The direct interaction and co-localization of N protein with MIF were confirmed by immunoprecipitation and confocal microscopy analysis, respectively. The mapping studies localized the critical N sequences for this interaction to amino acid 140-210 including SR motif by yeast two -hybrid system. To the best of our knowledge, this is the first report that SARS-N protein interacts with the MIF within host cells, which enhance our understanding of the molecular mechanisms of SARS replication.[...] Read More.

Keywords: Severe acute respiratory syndrome (SARS) coronavirus, nucleocapsid protein, Macro|phage migration inhibitory factor protein, yeast two-hybrid.

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Characterization of Staphylococcus spp strains isolated from hospital, community and environmental in Puebla city, Mexico

Ana Marta de los Ángeles Lobo-Sánchez, Patricia Lozano-Zaraín, Ygnacio Martínez-Laguna, Zita Gutiérrez-Cázarez, Antonio Rivera-Tapia, Carmen Torres and Rosa del Carmen Rocha-Gracia,*

Abstract: We investigated the prevalence of methicillin-resistant staphylococci (MRS) and evaluated the antimicrobial resistance patterns of 284 Staphylococcus strains isolated from two hospitals, as well as from community and the environment in Puebla City, Mexico. Isolates were identified by Gram-stain and biochemical reactions and antimicrobial susceptibility testing was performed by Kirby-Bauer and in some cases by determination of minimal inhibitory concentrations of antimicrobial agents. Result showed that from 284 strains studied, 32% (90 strains) were multidrug-resistant, of which 82% (74 strains) were methicillin-resistant. From 154 Staphylococcus aureus isolates tested, 41 strains showed methicillin-resistance (27%) and 84 of 130 coagulase-negative staphylococci showed methicillin-resistance (65%). The mecA gene was detected in 38 of 43 oxacillin-resistant staphylococci tested (14/14 S. aureus and 24/29 coagulase negative staphylococci). Nevertheless, this gene was also identified in 14 S. aureus that exhibited oxacillin and cefoxitin susceptibility. The percentages of resistance detected among S. aureus and coagulase negative staphylococcal isolates were: penicillin (79 and 67%, respectively), oxacillin (27 and 65%), erythromycin (18 and 36%), tetracycline (6 and 24%), gentamicin (71 and 45%), and trimethoprim sulfamethoxazole (19 and 37%). The b-lactamase production was positive in more than 80% of isolates. These results show the presence of multiresistant strains in these three sources, which supports the control measures taken by health authorities with respect to avoiding the misuse and abuse of antibiotics.[...] Read More.

Keywords: Staphylococcus, methicillin resistance Staphylococcus aureus (MRSA), methicillin resistance coagulase-negative staphylococci (MRCoNS), emerging infections.

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