Cnidarians as a source of new marine bioactive compounds--an overview of the last decade and future steps for bioprospecting

Marine invertebrates are rich sources of bioactive compounds and their biotechnological potential attracts scientific and economic interest worldwide. Although sponges are the foremost providers of marine bioactive compounds, cnidarians are also being studied with promising results. This diverse group of marine invertebrates includes over 11,000 species, 7500 of them belonging to the class Anthozoa. We present an overview of some of the most promising marine bioactive compounds from a therapeutic point of view isolated from cnidarians in the first decade of the 21st century. Anthozoan orders Alcyonacea and Gorgonacea exhibit by far the highest number of species yielding promising compounds. Antitumor activity has been the major area of interest in the screening of cnidarian compounds, the most promising ones being terpenoids (monoterpenoids, diterpenoids, sesquiterpenoids). We also discuss the future of bioprospecting for new marine bioactive compounds produced by cnidarians.     

Rigidin E,a New Pyrrolopyrimidine Alkaloid from a Papua New Guinea Tunicate Eudistoma Species

A new pyrrolopyrimidine alkaloid, rigidin E (1) and the known metabolites rigidin (2) and 1-methylherbipoline (3) have been isolated from a Papua New Guinea tunicate Eudistoma sp. A combination of spectroscopic data were used to determine the structures of these metabolites.     

Factors associated with seroprevalence of Neospora caninum in dairy cattle in southeastern Brazil

Neosporosis is an infectious disease caused by Neospora caninum, an obligate intracellular cyst-forming protozoan considered a major cause of miscarriage in dairy cattle in many parts of the world. This cross-sectional study evaluated the relationship between reproductive abnormalities and seropositivity to N. caninum in 1,204 dairy cows from 40 farms located in the state of Minas Gerais, southeastern Brazil. Producers were interviewed, and blood samples were collected to perform indirect immunofluorescence tests (IFAT 1:200). Association between reproductive abnormalities and seropositivity in cattle was evaluated with generalized estimating equations. The true herd-level seroprevalence of N. caninum was 95 % (83.3–99.1), while the individual-level true seroprevalence was 21.6 % (19.2–24.2). Several reproductive abnormalities were significantly associated with seropositivity to N. caninum: occurrence of repeated estrus (p?=?0.02; OR?=?3.84; 95 % CI?=?1.239–11.893), repeated miscarriages (p?=?0.001; OR?=?2.54; 95 % CI?=?1.423–5.402), and temporary anestrus (p?=?0.001; OR?=?3.44; 95 % CI?=?1.976–5.994). Furthermore, loose dogs (p?=?0.041; OR?=?2.20; 95 % CI?=?1.033–4.672) when fed raw meat (p?=?0.001; OR?=?1.91; 95 % CI?=?1.443–2.519) are risk factors for N. caninum infection. We observed that seropositivity to N. caninum in cattle increases risk of miscarriage by almost twice throughout the reproductive life of cows (p?=?0.004; OR?=?1.978; 95 % CI?=?1.249–3.131). Serologic evidence in this study indicates that N. caninum infection is widely distributed among dairy herds and significantly associated with reproductive disorders, especially miscarriage, repeated estrus, and temporary anestrus.     

Clinical,cytologic, and histologic features of a mammary micropapillary carcinoma in a dog

Mammary invasive micropapillary carcinoma is a rare variant of mammary carcinoma that was recently recognized in dogs. The cytologic features and biologic behavior of such neoplasms in dogs have not yet been widely discussed in the veterinary literature. We report the clinical, cytologic, and histologic features of a canine micropapillary carcinoma in a 13‐year‐old female mongrel dog. The mammary region presented with extreme local pain, severe edema and erythema, and multifocal epidermal ulceration, which is typical for an inflammatory mammary carcinoma. Fine‐needle aspirates were highly cellular and consisted of individual cells and papillary cell clusters with characteristics of malignant epithelial cells. Histologic examination revealed neoplastic cells arranged in small papillae without fibrovascular cores, sometimes inside clear lymphatic spaces, indicating lymphovascular invasion. Regional lymph node evaluation revealed metastatic cells. Due to deteriorating clinical condition the dog was euthanatized 5 months after mastectomy. At necropsy, metastatic neoplastic mammary cells were found in popliteal and mediastinal lymph nodes, the right femoral biceps muscle, liver, heart, lungs, and urinary bladder.     

Genetic diversity and gene flow in six accessions of Meso-America teosintes

The genus Zea (teosinte) has a native distribution from Mexico to Nicaragua (Meso-America region) and studies on teosinte species may help improve our understanding of maize genetics, population genetics, genome evolution and crop evolution. Moreover, since F1 hybrids between teosinte and maize are fertile, all teosinte species can potentially contribute to maize breeding in the form of traits such as resistance or tolerance to heavy metals in the soil and other adverse environmental conditions. Gene flow between maize and teosinte occurs in Mexico and Central America. This study analysed the genetic diversity of teosintes by using the microsatellite technique on a total of 120 individuals from six different species and 21 Simple Sequence Repeats (SSR). A total of 109 alleles were found and the number of alleles per locus ranged from 2 to 7. The genetic diversity varied between all species from 0.514 to 0.572, with a mean value of 0.548 (Nei index). Rare and unique alleles were detected in all species, with the highest frequencies found in Zea diploperennis Iltis, Doebley et Guzman, Zea perennis (Hitchc.) Reeves et Mangelsdorf and Zea nicaraguensis Iltis et Benz, which had more than seven rare alleles each. Analysis of molecular variance revealed that 19.87% of the variation between species was statistically significant (P < 0.001). When the different species were compared with the Wright (Fst) value, genetic variation between species was confirmed. The data also revealed a moderate rate gene flow between the species. Genetic diversity was found to be somewhat higher in Central America than in Mexico.     

Incorporation of dietary nitrogen from fish meal and pea meal (Pisum sativum) in muscle tissue of Pacific white shrimp (Litopenaeus vannamei) fed low protein compound diets

Stable isotope analyses were applied to explore the relative dietary nitrogen contributions from fish meal and pea meal (Pisum sativum) to muscle tissue of Pacific white shrimp postlarvae (141 ± 31 mg) fed low protein diets having different proportions of both ingredients as the sole dietary protein sources. A negative control diet was formulated to contain 100% pea meal and six more isoproteic diets to have decreasing levels of pea meal‐derived nitrogen: 95%, 85%, 70%, 55%, 40% and 0% of the initial level. Growth rates were negatively correlated to dietary pea protein inclusion due to progressive essential amino acid deficiencies (sulphur amino acids, threonine, lysine, histidine). The nitrogen turnover rate significantly increased in muscle tissue of shrimps fed diets having high levels of pea meal; however, contrary to observations from a previous study using soy protein, the relative contributions of dietary nitrogen from pea meal to shrimp muscle tissue were equal or higher than expected contributions established by the dietary formulations. Results highlight the effectiveness of stable isotope analysis in assessing the nutritional contributions of alternative ingredients for aquaculture feeds and the potential suitability of pea as a source of protein (provided the diets are nutritionally balanced).     

Fishes that rule the world: circumtropical distributions revisited

Briggs ( 1960 ) published the first checklist of circumtropical fishes with 107 species. This work served for a half century as the most comprehensive checklist of globally distributed fishes, but the intervening years witnessed many discoveries, and molecular data have changed the way we evaluate species. Here, we update the list guided by taxonomic revisions, phylogenies, phylogeographic data and DNA barcodes. The resulting list now includes 284 species. The dramatic increase is primarily due to two trends: (i) continued oceanic exploration leading to range revisions and species discoveries and (ii) public databases such as FishBase and the Catalogue of Fishes make range data more accessible. Five species were removed from the list as closer scrutiny revealed multiple taxa, 14 were removed due to updated range information, and 35 more are suspected to be species complexes. The species listed here are mostly pelagic and bathypelagic fishes. Euryhaline, anadromous, catadromous, freshwater, and with few exceptions, reef fishes do not achieve global distributions. The most species‐rich family of marine fishes (Gobiidae) is absent. The fishes with the longest pelagic larval stage (Anguillidae) are absent. In contrast, requiem sharks (Carcharhinidae), tunas (Scombridae), jacks (Carangidae), remoras (Echeneidae) and especially lanternfishes (Myctophidae) have multiple representatives. The combined evidence indicates that high mobility as an adult is a key requirement to achieve a global distribution. Many others are members of monotypic genera or families, indicating old lineages that did not diversify. We conclude that global ranges may promote persistence over evolutionary timescales, but also reduce opportunities for speciation.     

Conception rate,uterine infection and embryo quality after artificial insemination and natural breeding with a stallion carrier of Pseudomonas aeruginosa: a case report

Background

Pseudomonas aeruginosa may cause venereal disease and infertility in horses. A Pseudomonas aeruginosa - carrier stallion, often unresponsive to artificial vagina collection, was used to naturally breed mares. Semen collected from the same stallion was also used to perform artificial inseminations. Pregnancy rates, embryo quality and incidence of uterine infection were compared between inseminated or naturally-bred mares.

Methods

P. aeruginosa was isolated from swabbing of the penis, prepuce and distal urethra of the stallion. Before being bred or inseminated, clitoral/vestibular samples were collected from all mares, and cultured for isolation of P. aeruginosa. At the first observed estrus, endometrial swabs were also collected. All mares subjected to natural mating (NS) were re-evaluated for P.aeruginosa by culture of clitoral and endometrial swabs. Artificial inseminations (AI) were performed either with fresh-extended semen (11 AI/7 mares) or frozen semen (10 AI/7 mares). The stallion was also used to breed 3 mares (4 services). For embryo collection, 2 mares were inseminated with fresh-extended semen (1 AI/mare), and 2 additional mares were inseminated with frozen semen (2 AI/mare). Two mares were naturally-bred with a total of 9 services, for embryo collection. All mares were examined after AI or natural service (NS), for uterine pathologies. Embryo recoveries were attempted passing a catheter with inflatable cuff connected to a sterile flexible 2-way flushing catheter, through the cervix. Flushed media was recovered into an Em-Con filter, and embryos searched using a stereoscope. Embryos were graded from 1 (excellent) to 4 (degenerated/dead).

Results

Pregnancy rates obtained after NS was 50% per cycle. However, more than half of the NS resulted in uterine disease, while uterine pathology was seen only in 22% of the time following AI. Half of the mares bred by NS got positive to P. aeruginosa. Percentage of embryo recovery rates was identical after AI or NS (66.7%). The 4 embryos recovered after AI were classified as Grade 1, while after NS only 2 out of the 6 recovered embryos were Grade 1.

Conclusion

a) there was no evidence of reduced fertilization after AI or NS, b) a numerically higher incidence of uterine disease was noticed after NS, c) venereal transmission of P. aeruginosa after NS was confirmed, d) a lower percentage of G1 embryos may be obtained after NS. Overall, the data supports the indication for P. aeruginosa-carrier stallions to be bred by AI rather than by NS, and raises the possibility that P. aeruginosa may affect embryo quality.