scholarly journals Discrimination of species and populations of the genus Cichla (Cichliformes: Cichlidae) in rivers of the Amazon basin using otolithic morphometry

2021 ◽  
Vol 19 (4) ◽  
Author(s):  
Marcos A. Mereles ◽  
Raniere G. C. Sousa ◽  
Lorenzo S. A. Barroco ◽  
Caroline P. Campos ◽  
Marc Pouilly ◽  
...  

ABSTRACT The genus Cichla is a highly diverse group, with 16 species already described. Externally, some species are very similar and discriminating between them may be very difficult. Nevertheless, discrimination of fish stocks is essential for management purposes. Morphometric analyses of otoliths have been successfully used to distinguish species and fish stocks, especially in marine environments. This study evaluated whether sagittal otolith shape can be used to discriminate among the species Cichla temensis, C. monoculus, and C. orinocensis, as well as within populations of C. temensis in rivers of the Amazon. Shape indices and Fourier coefficients were used to describe the shape of the otoliths. Among the groups of species, the morphology of the sagittal otolith of C. temensis was totally distinct from the species C. monoculus and C. orinocensis. While among populations of C. temensis, individuals from the Negro and Jatapú Rivers were different, regardless of the methods used. These results confirm the ability to differentiate species and populations by using the morphology of otoliths. However, more research is needed to verify the role of genetic versus environmental and biotic effects, and thus be able to explain the discrimination observed in otoliths.

2019 ◽  
Vol 54 (1) ◽  
pp. 144
Author(s):  
Cecilia Machuca ◽  
Francisco Cerna ◽  
Lizandro Muñoz

Anchovy (Engraulis ringens) population units were analyzed in three zones off the coast of Chile: 1: Arica-Iquique, 2: Coquimbo and 3: Talcahuano-Valdivia from samples obtaineds during the 2012 spawning season. We used 50 left sagittae otoliths from each zone to perform a morphometric analysis, which included basic measurements, shape indexes and contour analysis (elliptical Fourier analysis). A MANOVA and Tukey multiple comparison analyses, applied on basic measures and shape indexes showed significant differences between zone 3 and zones 1 and 2. A classification by Canonical Discriminant analysis of elliptical Fourier harmonics, indicated significant differences among zones. It is concluded, therefore, that otolith shape analysis could be used to discriminate population units of Engraulis ringens. Better results were achieved using elliptic Fourier coefficients than using only shape indices.


ZooKeys ◽  
2020 ◽  
Vol 915 ◽  
pp. 59-86 ◽  
Author(s):  
Mateo Basantes ◽  
Nicolás Tinoco ◽  
Paúl M. Velazco ◽  
Melinda J. Hofmann ◽  
Miguel E. Rodríguez-Posada ◽  
...  

The Stripe-headed Round-eared bat, Tonatia saurophila, includes three subspecies: Tonatia saurophila saurophila (known only from subfossil records in Jamaica), Tonatia saurophila bakeri (distributed from southeastern Mexico to northern Colombia, Venezuela west and north of the Cordillera de Mérida, and northwestern Ecuador), and Tonatia saurophila maresi (distributed in Venezuela east and south of the Cordillera de Mérida, the Guianas, Trinidad and Tobago, northeastern Brazil, and along the upper Amazon basin in Colombia, Ecuador, Peru, and Bolivia). The last two subspecies are an attractive example to test predictions about the historical role of the Andes in mammalian diversification. Based on morphological descriptions, morphometric analyses, and phylogenetic reconstruction using the mitochondrial gene Cyt-b and the nuclear exon RAG2, this study evaluates the intraspecific relationships within Tonatia saurophila and the taxonomic status of the taxon. The three subspecies of T. saurophila are recognizable as full species: Tonatia bakeri, Tonatia maresi, and Tonatia saurophila. The latter is restricted to its type locality and possibly is extinct. Tonatia bakeri, in addition to being larger than T. maresi, is morphologically distinguishable by possessing an acute apex at the posterior edge of the skull, a well-developed clinoid process, and relatively robust mandibular condyles, and by lacking a diastema between the canine and the first lower premolar. The genetic distance between T. bakeri and T. maresi is 7.65%.


2021 ◽  
Vol 9 ◽  
pp. 2050313X2199719
Author(s):  
Sundus Bilal ◽  
Saad Muhammad Saeed ◽  
Muhammad Zeeshan Siddique ◽  
Muhammad Saqib ◽  
Shafqat Mehmood ◽  
...  

The role of self-expandable metallic stents is gradually evolving for a diverse group of benign and malignant gastrointestinal tract problems, with luminal obstruction being by far the most common. Although its role in refractory variceal bleeding is well established, it has rarely been tried for tumor-related bleeding, with only a few case reports in this regard. We share our experience of successfully controlling esophageal tumor–related bleeding with the use of a fully covered self-expandable metallic stent. A 58-year-old woman with irresectable distal esophageal cancer, presented with hematemesis. Esophago-gastro-duodenoscopy revealed an obstructing esophageal tumor with diffuse oozing of blood. This was unamenable to local injection of adrenaline and hemospray; therefore, a temporary self-expandable metallic stent was parked to create a tamponade effect. This successfully stopped bleeding and the patient remained asymptomatic till discharge. However, she was lost to follow-up, and therefore, the stent was removed after a period of 5 months instead of 2 weeks.


2009 ◽  
Vol 66 (8) ◽  
pp. 1652-1661 ◽  
Author(s):  
Mike Sinclair

Abstract Sinclair, M. 2009. Herring and ICES: a historical sketch of a few ideas and their linkages. – ICES Journal of Marine Science, 66: 1652–1661. This introduction to the Symposium on “Linking Herring” sketches the development of some ideas generated from herring research within an ICES context. The work of Committee A (1902–1908), under the leadership of Johan Hjort, led to a paradigm shift from “migration thinking” to “population thinking” as the interpretation of fluctuations in herring landings. From the 1920s to the 1950s, the focus on forecasting services for the herring fisheries, although ultimately unsuccessful, had the unintended consequence of generating ideas on recruitment overfishing and the match–mismatch hypothesis. The collapse of the East Anglian fishery led, in 1956, to considerable debate on its causes, but no consensus was reached. Three consecutive symposia dealing with herring (1961, 1968, and 1970) reveal a changing perspective on the role of fishing on recruitment dynamics, culminating in Cushing’s 1975 book (“Marine Ecology and Fisheries”, referred to here as the “Grand Synthesis”), which defined the concept of recruitment overfishing and established the future agenda for fisheries oceanography. The 1978 ICES “Symposium on the Assessment and Management of Pelagic Fish Stocks” is interpreted as the “Aberdeen Consensus” (i.e. without effective management, recruitment overfishing is to be expected). In conclusion, herring research within ICES has led to many ideas and two major paradigm shifts.


Author(s):  
Vikas Pathak ◽  
Rinchen N. Bhutia ◽  
Shashi Bhushan ◽  
Geetanjali Deshmukhe ◽  
A.K. Jaiswar

Background: The fishes of family Gobiidae are one of the least studied fishes, especially for otolith structure. The otoliths were possess species specific features. Hence, traits of sagittal otolith of gobid species studied. Methods: Five gobid species Odontamblyopus roseus (Valenciennes, 1837), Trypauchen vagina (Bloch and Schneider, 1801), Glossogobius giuris (Hamilton, 1822), Parachaeturichthys polynema (Bleeker, 1853) and Boleophthalmus dussumieri (Valenciennes, 1837) were investigated by three methods including morphological, shape indices and step wise discriminant function analysis (SDFA). Result: Interrelationship between shape indices investigated, at 95% level of confidence (P less than 0.05), revealed that perimeter of P. polynema and area of T. vagina have isometric growth with their length (b = 3.0071, 2.90, respectively) and otolith area of B. dussumieri have positive allometric growth (b = 4.23077). SDFA, based on otolith morphometry, discriminated species up with 97.18% accuracy. Hence, the results of present investigation can be used for discrimination of the species and as a tool in predicting fish size from the otoliths and in calculating the biomass of these less studied fish species.


Author(s):  
Elroy Patrick Weledji ◽  
George Enow Orock

Non-Hodgkin lymphomas (NHLs) are a diverse group of blood cancers derived from lymphocytes that vary significantly in their severity. Surgery is not often used as a treatment because of the efficacy of chemotherapy, biological therapy, radiotherapy and hematopoietic stem cell transplantation. We reviewed the natural history and possible role of surgery for NHL. Surgery may be useful in confirming or refuting an equivocal radiological diagnosis through biopsy, removing symptomatic limited disease from an affected organ and in splenectomy for primary splenic lymphoma. Emergency abdominal surgery for acute complications of NHL provides palliation and diagnosis. There is as yet no consensus as to the optimum treatment for symptomatic limited disease affecting an organ and timing of chemotherapy perioperatively. Prospective randomized trials are required.


2015 ◽  
Author(s):  
Sive Finlay ◽  
Natalie Cooper

Morphological diversity is often studied qualitatively. However, to truly understand the evolution of exceptional diversity, it is important to take a quantitative approach instead of relying on subjective, qualitative assessments. Here, we present a quantitative analysis of morphological diversity in a Family of small mammals, the tenrecs (Afrosoricida, Tenrecidae). Tenrecs are often cited as an example of an exceptionally morphologically diverse group. However, this assumption has not been tested quantitatively. We use geometric morphometric analyses of skull shape to test whether tenrecs are more morphologically diverse than their closest relatives, the golden moles (Afrosoricida, Chrysochloridae). Tenrecs occupy a wider range of ecological niches than golden moles so we predict that they will be more morphologically diverse. Contrary to our expectations, We find that tenrec skulls are only more morphologically diverse than golden moles when measured in lateral view. Furthermore, similarities among the species-rich Microgale tenrec Genus appear to mask higher morphological diversity in the rest of the Family. These results reveal new insights into the morphological diversity of tenrecs and highlight the importance of using quantitative methods to test qualitative assumptions about patterns of morphological diversity.


Author(s):  
Akshay Vaidya

Viral infections remain major “worldwide” cause of morbidity and mortality.  Herbal extracts or wholesome drugs have been in use for medicinal purposes since ancient time and are known for their antiviral properties and more tolerable side effects. Thus, naturally based pharmacotherapy is a proper alternative for treating viral diseases. Hence this article describes potential antiviral properties of medicinal plants against diverse group of viruses and suggests screening the potential of plants possessing broad spectrum anti-viral effects against viral diseases. Guduchyadi Kwath is a polyherb ayurvedic preparation useful in various diseases. It is useful in pitta vikar, shleshma vikar, Jwara, Chardi, Daha, Trushna, and Agnimandya1. According to modern science it showed anti-inflammatory, antioxidant, antibacterial, antiviral, antimalarial, hepatoprotective, wound healing and immune-modulatory action. The study is aim to the effect of “Guduchyadi kashaya” on viral diseases.


1992 ◽  
Vol 3 (4) ◽  
pp. 307-332 ◽  
Author(s):  
Libuse A. Bobek ◽  
Michael J. Levine

The cystatin superfamily of proteins, derived from a common ancestor, is comprised of a diverse group of potent cysteine proteinase inhibitors and antibacterial/viral agents grouped into several families. This review concentrates on family 2 cystatins, namely, the human salivary cystatins and cystatin C. Emphasis is given to their physicochemical and functional properties at both the protein and the molecular level. The role of cystatins in disease processes, including those in the oral cavity, is also discussed. Finally, future directions for cystatin research in oral biology are presented.


Development ◽  
1995 ◽  
Vol 121 (8) ◽  
pp. 2559-2567 ◽  
Author(s):  
P. Souza ◽  
M. Kuliszewski ◽  
J. Wang ◽  
I. Tseu ◽  
A.K. Tanswell ◽  
...  

The biological role of platelet-derived growth factor (PDGF)-AA in lung morphogenesis was investigated by incubating embryonic lung explants with phosphorothioate antisense PDGF-A oligonucleotides, which decreased PDGF-AA but not PDGF-BB protein content. Antisense PDGF-A oligonucleotides inhibited DNA synthesis. This inhibitory effect of antisense PDGF-A was reversed by the addition of exogenous PDGF-AA but not PDGF-BB. Morphometric analyses of antisense-treated cultures showed a significant reduction in lung size. The number of terminal buds of the lung explants was significantly decreased by antisense PDGF-A oligonucleotides. PDGF-AA but not PDGF-BB attenuated the inhibitory effect of antisense PDGF-A on early lung branching. Sense PDGF-A had no effect on DNA synthesis and early lung branching. Reverse transcriptase-polymerase chain reaction analysis revealed PDGF-A mRNA expression in the epithelial component of the embryonic lung, while message for PDGF alpha-receptor was expressed in the mesenchyme. Incubation of explants with neutralizing PDGF-AA antibodies also reduced DNA synthesis and early branching morphogenesis. We conclude that PDGF-AA and its receptor represent an important epithelial-mesenchymal interaction which plays a critical role in early lung branching morphogenesis.


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