Showing papers by "Saleh A. Al-Farraj published in 2011"

Application of an indicator based on taxonomic relatedness of ciliated protozoan assemblages for marine environmental assessment

Abstract: Ciliated protozoa play important roles in aquatic ecosystems especially regarding their functions in micro-food web and have many advantages in environmental assessment compared with most other eukaryotic organisms. The aims of this study were focused on analyzing the application of an indicator based on taxonomic relatedness of ciliated protozoan assemblages for marine environmental assessment. The spatial taxonomic patterns and diversity measures in response to physical–chemical variables were studied based on data from samples collected during 1-year cycle in the semi-enclosed Jiaozhou Bay, northern China. The spatial patterns of ciliate communities were significantly correlated with the changes of environmental status. The taxonomic distinctness (Δ*) and the average taxonomic distinctness (Δ+) were significantly negatively correlated with the changes of nutrients (e.g., nitrate nitrogen and soluble active phosphate; P < 0.05). Pairwise indices of Δ+ and the variation in taxonomic distinctness (Λ+) showed a decreasing trend of departure from the expected taxonomic breadth in response to the eutrophication stress and anthropogenic impact. The taxonomic relatedness (especially the pairwise Δ+ and Λ+) indices of ciliate communities are robust as an indicator with scientifically operational value in marine environmental assessment.

The Diversity of Scuticociliates (Protozoa, Ciliophora): A Report on Eight Marine Forms Found in Coastal Waters of China, with a Description of One New Species

Abstract: Eight marine scuticociliates, Pseudoplatynematum denticulatum (Kahl, 1933) nov. comb., Protocyclidium sinica nov. spec., Histiobalantium marinum Kahl, 1933, Porpostoma notata Mobius, 1888, Philaster hiatti Thompson, 1969, Parauronema longum Song, 1995, Uronemella parafilificum Gong et al., 2007, and Paranophrys magna Borror, 1972, collected from Chinese coastal waters, were investigated using live observations and silver impregnation methods. Investigations of a Chinese population of Platynematum denticulatum (Kahl, 1933) reveal that it has a highly strengthened pellicle and distinct spines and thus corresponds well with the definition of Pseudoplatynematum Bock, 1952. A new combination, Pseudoplatynematum denticulatum (Kahl, 1933) nov. comb., is therefore proposed and an improved species diagnosis is supplied. Protocyclidium sinica nov. spec. is characterized by: small body size with buccal field approximately 60% of body length; extrusomes present; 13 or 14 somatic kineties; somatic kinety 1 comprising approximately 24 densely arranged kinetids; somatic kinety n shortened posteriorly; single macronucleus. Additional information is documented on the morphology of six other species of scuticociliates based on the China populations.

Molecular evolution of Cinetochilum and Sathrophilus (Protozoa, Ciliophora, Oligohymenophorea), two genera of ciliates with morphological affinities to scuticociliates

Abstract: Zhang, Q., Miao, M., Struder-Kypke, M. C., Al-Rasheid, K. A. S., Al-Farraj, S. A. & Song, W. (2011). Molecular evolution of Cinetochilum and Sathrophilus (Protozoa, Ciliophora, Oligohymenophorea), two genera of ciliates with morphological affinities to scuticociliates. —Zoologica Scripta, 40, 317–325. The ciliate order Loxocephalida sensu Li et al. (2006) has been considered to be systematically uncertain within the subclass Scuticociliatia. Loxocephalids display mixed morphological features and morphogenetic patterns that are found in two different oligohymenophorean subclasses: scuticociliates and hymenostomes. To reveal their phylogenetic positions, molecular information on this group is urgently needed but still inadequate. In the present study, we have sequenced the small subunit rRNA gene of two newly described loxocephalids, Cinetochilum ovale Gong & Song 2008; and Sathrophilus planus Fan et al. 2010; which have never been discussed based on molecular analysis. Results show: (i) all phylogenetic trees are nearly identical in placing Cinetochilum closest to the subclass Apostomatia and form a monophyletic group divergent from the typical scuticociliates, (ii) the genus Sathrophilus, together with Anoplophrya, a poorly known Astomatia, forms a peripheral branch separated from the scuticociliatian assemblage and (iii) the affiliation of the loxocephalid genera sensu Li et al. (2006) is not confirmed due to a dispersion in four deeply diverged clades. In addition, the polyphyly of the genus Cyclidium, shown in previous studies, is confirmed by our phylogenetic analyses and supported by the approximately unbiased test based on the new database in this work.

Taxonomy, morphology and molecular systematics of a new oligotrich ciliate, Williophrya maedai gen. nov., sp. nov., with redescriptions of Strombidium basimorphum and Pseudotontonia simplicidens (Protozoa, Ciliophora, Oligotrichia)

Abstract: The morphology and small subunit rRNA (SSrRNA) gene sequence of a marine oligotrich ciliate, Williophrya maedai gen. nov., sp. nov., are reported. The new genus Williophrya is characterized by the adoral zone with no differentiation of membranelles, and the reduced somatic ciliature which comprises a bipartite girdle kinety only. In addition, the in vivo morphologies of two other oligotrichs, namely Strombidium basimorphum Martin & Montagnes, 1993 and Pseudotontonia simplicidens (Lynn & Gilron, 1993) Agatha, 2004, are reported for the first time based on Chinese populations. Improved diagnoses of both species are supplied. The phylogenetic position of Williophrya maedai is investigated based on SSrRNA gene sequence data. These show that: (1) Williophrya maedai is most closely related to Strombidium purpureum and S. apolatum; (2) Williophrya is assigned to the family Strombidiidae although it has some unique morphological features regarding its oral and somatic ciliatures.

Redescriptions of Two Marine Scuticociliates from China, with Notes on Stomatogenesis in Parauronema longum (Ciliophora, Scuticociliatida)

Abstract: The morphology and infraciliature of two marine scuticociliates, Pleuronema puytoraci Groliere and Detcheva, 1974, and Parauronema longum Song, 1995, collected from China, were investigated using live observation and protargol impregnation methods. Based on the data obtained for the China population, new information of the living morphology of Pleuronema puytoraci is documented and details of the complete infraciliature is available for the first time. The stomatogenesis of Parauronema longum is basically similar to that of its congeners and can be summarized as follows: membranelle 1, membranelle 2 and the scutica of the opisthe originate from the parental paroral membrane, whereas membranelle 3 of the opisthe develops from the parental scutica; the paroral membrane originates from the parental paroral membrane.

Insights into the phylogeny of sporadotrichid ciliates (Protozoa, Ciliophora: Hypotricha) based on genealogical analyses of multiple molecular markers

Abstract: The sporadotrichid ciliates are an especially diverse group. A number of investigators have studied the morphological, morphogenetic, and molecular relationships among members of this group. Despite this, a consistent classification is still lacking and several important questions about the phylogenetic relationships within this group remain unsolved. To improve our understanding of these relationships, we constructed phylogenetic trees using the nucleotide sequences of the small-subunit rRNA (SSrRNA) gene and amino acid sequences of actin I and α-tubulin. Analyses of SSrRNA gene sequences indicated that: 1) the Sporadotrichida sensu Lynn (2008) and the Oxytrichidae are polyphyletic; 2) the Uroleptus species, which are classified to urostylids, formed a sister group with the oxytrichids; 3) Halteria grandinella, which is grouped morphologically with oligotrich species, clustered within the oxytrichids. These results are congruent with previous studies based on SSrRNA gene sequences. However, the amino acid sequences of actin I and α-tubulin yielded different topologies. The main results are: 1) in all phylogenetic trees, the genus Oxytricha was paraphyletic; 2) Uroleptus was sister to a subset of Urostyla and Holosticha, albeit with low supporting values; 3) Halteria grandinella was separated distantly from the Oxytrichidae in trees inferred from actin I amino acid sequences but clustered with oligotrichids in the α-tubulin analysis. The inconsistency among the trees inferred from these different molecular markers may be caused by rapidly accumulated genetic characterizations of ciliates. Further studies with additional molecular markers and sampling of more taxa are expected to better address the relationships among sporadotrichids.

Cytokine genes expression in mice hepatocytes during malaria infection

Abstract: The aim of this study was to investigate the inflammation genes (IL-1β, IL-6, TNF-α and iNos) responses to Plasmodium chabaudi malaria in the liver of female C57BL/6 hepatocytes via mRNA expression due to infection with P. chabaudi at different time points. Mice were injected intraperitoneally (ip) with 106 P. chabaudi-infected erythrocytes and then scarified at days (0, 1, 4 and 8 respectively). RT-PCR was used to quantify liver inflammation genes. The levels of IL-1β, IL-6 and TNFα were significantly increased at days 1 and 8. The total iNos were significantly increased at all days after infection. In conclusion, present data has shown that infection with P. chabaudi stimulated infalammation genes in the liver. Thus, we suggest the implication of oxidative stress due to outcome of malaria in mice hepatocytes according to its natural function need to be confirmed with a larger number of samples to be used as a reliable inflammation detection method. Key words: Inflammation, malaria, mice, liver.

Scrotal, testicular and semen characteristics of the mountain gazelle (Gazella gazella ) males

Abstract: This study aimed to evaluate seasonal differences in the characteristics of various male reproductive organs and in semen quality. Ten adult males of mountain gazelles (Gazella gazelle) were used in this study during summer and winter. The results showed significant differences in July to September versus October to December for volume (P≤0.05), motility and viability (P≤0.01), progressive motility, and morphologic alteration (P≤0.001). Hence it was concluded that sperm characteristics are strongly influenced by season. This study therefore suggested that the suitable period for semen collection is the breeding season (October to December), which has a good quality for manipulation and long-term preservation of G. gazelle in Saudi Arabia. Key words: Gazelle, reproduction, semen, sperm, cryopreservation.