scholarly journals Tetrodotoxins Secretion and Voltage-Gated Sodium Channel Adaptation in the Ribbon Worm Kulikovia alborostrata (Takakura, 1898) (Nemertea)

Toxins ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 606
Author(s):  
Anna E. Vlasenko ◽  
Vasiliy G. Kuznetsov ◽  
Grigorii V. Malykin ◽  
Alexandra O. Pereverzeva ◽  
Peter V. Velansky ◽  
...  
Keyword(s):  
Sanger Sequencing ◽  
Pcr Amplification ◽  
The Body ◽  
Specific Primers ◽  
Voltage Gated ◽  
In Captivity ◽  
Loop Regions ◽  
Low Probability ◽  
Marine Worms ◽  
Immunohistological Study

Nemertea is a phylum of marine worms whose members bear various toxins, including tetrodotoxin (TTX) and its analogues. Despite the more than 30 years of studying TTXs in nemerteans, many questions regarding their functions and the mechanisms ensuring their accumulation and usage remain unclear. In the nemertean Kulikovia alborostrata, we studied TTX and 5,6,11-trideoxyTTX concentrations in body extracts and in released mucus, as well as various aspects of the TTX-positive-cell excretion system and voltage-gated sodium (Nav1) channel subtype 1 mutations contributing to the toxins’ accumulation. For TTX detection, an immunohistological study with an anti-TTX antibody and HPLC-MS/MS were conducted. For Nav1 mutation searching, PCR amplification with specific primers, followed by Sanger sequencing, was used. The investigation revealed that, in response to an external stimulus, subepidermal TTX-positive cells released secretions actively to the body surface. The post-release toxin recovery in these cells was low for TTX and high for 5,6,11-trideoxyTTX in captivity. According to the data obtained, there is low probability of the targeted usage of TTX as a repellent, and targeted 5,6,11-trideoxyTTX secretion by TTX-bearing nemerteans was suggested as a possibility. The Sanger sequencing revealed identical sequences of the P-loop regions of Nav1 domains I–IV in all 17 studied individuals. Mutations comprising amino acid substitutions, probably contributing to nemertean channel resistance to TTX, were shown.

Organization, Expression and Evolution of a Disease Resistance Gene Cluster in Soybean

Genetics ◽  
2002 ◽  
Vol 162 (4) ◽  
pp. 1961-1977
Author(s):  
Michelle A Graham ◽  
Laura Fredrick Marek ◽  
Randy C Shoemaker
Keyword(s):  
Disease Resistance ◽  
Resistance Gene ◽  
Resistance Genes ◽  
Developmental Stages ◽  
Gene Evolution ◽  
Pcr Amplification ◽  
Disease Resistance Genes ◽  
Disease Resistance Gene ◽  
R Genes ◽  
Specific Primers

Abstract PCR amplification was previously used to identify a cluster of resistance gene analogues (RGAs) on soybean linkage group J. Resistance to powdery mildew (Rmd-c), Phytophthora stem and root rot (Rps2), and an ineffective nodulation gene (Rj2) map within this cluster. BAC fingerprinting and RGA-specific primers were used to develop a contig of BAC clones spanning this region in cultivar “Williams 82” [rps2, Rmd (adult onset), rj2]. Two cDNAs with homology to the TIR/NBD/LRR family of R-genes have also been mapped to opposite ends of a BAC in the contig Gm_Isb001_091F11 (BAC 91F11). Sequence analyses of BAC 91F11 identified 16 different resistance-like gene (RLG) sequences with homology to the TIR/NBD/LRR family of disease resistance genes. Four of these RLGs represent two potentially novel classes of disease resistance genes: TIR/NBD domains fused inframe to a putative defense-related protein (NtPRp27-like) and TIR domains fused inframe to soybean calmodulin Ca2+-binding domains. RT-PCR analyses using gene-specific primers allowed us to monitor the expression of individual genes in different tissues and developmental stages. Three genes appeared to be constitutively expressed, while three were differentially expressed. Analyses of the R-genes within this BAC suggest that R-gene evolution in soybean is a complex and dynamic process.

Telomere Length and Arsenic: Improving Animal Models of Toxicity by Choosing Mice With Shorter Telomeres

2021 ◽  
Vol 40 (3) ◽  
pp. 211-217
Author(s):  
Brayden Whitlock
Keyword(s):  
Animal Models ◽  
Telomere Length ◽  
Mouse Models ◽  
Arsenic Exposure ◽  
Tumor Formation ◽  
The Body ◽  
Cancer Resistance ◽  
Selective Pressures ◽  
Toxicity Monitoring ◽  
In Captivity

Arsenic is both a chemotherapeutic drug and an environmental toxicant that affects hundreds of millions of people each year. Arsenic exposure in drinking water has been called the worst poisoning in human history. How arsenic is handled in the body is frequently studied using rodent models to investigate how arsenic both causes and treats disease. These models, used in a variety of arsenic-related testing, from tumor formation to drug toxicity monitoring, have virtually always been developed from animals with telomeres that are unnaturally long, likely because of accidental artificial selective pressures. Mice that have been bred in captivity in laboratory conditions, often for over 100 years, are the standard in creating animal models for this research. Using these mice introduces challenges to any work that can be affected by the length of telomeres and the related capacities for tissue repair and cancer resistance. However, arsenic research is particularly susceptible to the misuse of such animal models due to the multiple and various interactions between arsenic and telomeres. Researchers in the field commonly find mouse models and humans behaving very differently upon exposure to acute and chronic arsenic, including drug therapies which seem safe in mice but are toxic in humans. Here, some complexities and apparent contradictions of the arsenic carcinogenicity and toxicity research are reconciled by an explanatory model that involves telomere length explained by the evolutionary pressures in laboratory mice. A low-risk hypothesis is proposed which has the power to determine whether researchers can easily develop more powerful and accurate mouse models by simply avoiding mouse lineages that are very old and have strangely long telomeres. Swapping in newer mouse lineages for the older, long-telomere mice may vastly improve our ability to research arsenic toxicity with virtually no increase in cost or difficulty of research.

scholarly journals Numerous uncharacterized and highly divergent microbes which colonize humans are revealed by circulating cell-free DNA

2017 ◽  
Vol 114 (36) ◽  
pp. 9623-9628 ◽  
Author(s):  
Mark Kowarsky ◽  
Joan Camunas-Soler ◽  
Michael Kertesz ◽  
Iwijn De Vlaminck ◽  
Winston Koh ◽  
...  
Keyword(s):  
Human Body ◽  
Sequence Data ◽  
Human Microbiome ◽  
Pcr Amplification ◽  
The Body ◽  
Direct Pcr ◽  
Cell Free Dna ◽  
Free Dna ◽  
Novel Taxa ◽  
Circulating Cell Free Dna

Blood circulates throughout the human body and contains molecules drawn from virtually every tissue, including the microbes and viruses which colonize the body. Through massive shotgun sequencing of circulating cell-free DNA from the blood, we identified hundreds of new bacteria and viruses which represent previously unidentified members of the human microbiome. Analyzing cumulative sequence data from 1,351 blood samples collected from 188 patients enabled us to assemble 7,190 contiguous regions (contigs) larger than 1 kbp, of which 3,761 are novel with little or no sequence homology in any existing databases. The vast majority of these novel contigs possess coding sequences, and we have validated their existence both by finding their presence in independent experiments and by performing direct PCR amplification. When their nearest neighbors are located in the tree of life, many of the organisms represent entirely novel taxa, showing that microbial diversity within the human body is substantially broader than previously appreciated.

scholarly journals Specific DNA identification of Pheretima in the Naoxintong capsule

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Xiaoxiao Zhu ◽  
Hoi-Yan Wu ◽  
Pang-Chui Shaw ◽  
Wei Peng ◽  
Weiwei Su
Keyword(s):  
Pcr Amplification ◽  
Cerebrovascular Diseases ◽  
Coi Gene ◽  
Chemical Marker ◽  
Dna Identification ◽  
Specific Primers ◽  
Blast Search ◽  
Pcr Products ◽  
Crude Drugs ◽  
Nucleotide Database

Abstract Background Pheretima is a minister drug in Naoxintong capsule (NXTC), a well-known traditional Chinese medicine (TCM) formula for the treatment of cardiovascular and cerebrovascular diseases. Owing to the loss of morphological and microscopic characteristics and the lack of recognized chemical marker, it is difficult to identify Pheretima in NXTC. This study aims to evaluate the feasibility of using DNA techniques to authenticate Pheretima, especially when it is processed into NXTC. Methods DNA was extracted from crude drugs of the genuine and adulterant species, as well as nine batches of NXTCs. Based on mitochondrial cytochrome c oxidase subunit I (COI) gene, specific primers were designed for two genera of genuine species, Metaphire and Amynthas, respectively. PCR amplification was performed with the designed primers on crude drugs of Pheretima and NXTCs. The purified PCR products were sequenced and the obtained sequences were identified to species level with top hit of similarity with BLAST against GenBank nucleotide database. Results Primers MF2R2 and AF3R1 could amplify specific DNA fragments with sizes around 230–250 bp, both in crude drugs and NXTC. With sequencing and the BLAST search, identities of the tested samples were found. Conclusion This study indicated that the molecular approach is effective for identifying Pheretima in NXTC. Therefore, DNA identification may contribute to the quality control and assurance of NXTC.

scholarly journals Comparison of Cranial and External Morphology of Tree Squirrels (Funiscurus leucogenys) in Selected Locations of Rainforest in Nigeria

2020 ◽  
pp. 1-12
Author(s):  
A. O. Bamidele ◽  
A. I. Akinpelu
Keyword(s):  
External Genitalia ◽  
The Body ◽  
Wire Mesh ◽  
Cranial Morphology ◽  
Generic Level ◽  
History Museum ◽  
Cranial Measurements ◽  
In Captivity ◽  
Tree Squirrels ◽  
Body Parameters

This study looked at the differences in cranial morphology of tree squirrel species (F. leucogenys) from four different locations in Rainforest part of Nigeria. The squirrels were captured through the use of locally fabricated live traps made of wire-mesh and steel. Trapped specimens were immediately transferred to the laboratory in captivity cages, where they were euthanized in a bell-jar containing chloroform-soaked cotton wool. Specimens were then preliminarily identified to the generic level, using an identification key. The skull of 131 tree squirrels were prepared using Long Island Natural History Museum guide and the sex of the specimens was determined by visual inspection of the external genitalia. The skull and other body parameters were measured using digital venier caliper. The results showed that the body parameters (HBL, TL, TBL, EL, HFL and BW) measured were slightly different from one location to another. Also, the cranial measure showed some similarities among some locations (Ile-Ife, Emure-Ekiti and Ado-Ekiti), while measurement on squirrels from Sekona was different from other three locations. In conclusion, the cranial measurements of the tree squirrels shows there was no new species of F. leucogeny from the sampled locations.

scholarly journals Coprological survey of protostrongylid infections in antelopes from Souss-Massa National Park (Morocco)

2020 ◽  
Vol 57 (4) ◽  
pp. 306-313
Author(s):  
A. Saidi ◽  
R. Mimouni ◽  
F. Hamadi ◽  
W. Oubrou
Keyword(s):  
National Park ◽  
Parasite Species ◽  
Pcr Amplification ◽  
Internal Transcribed Spacer Region ◽  
Mean Values ◽  
Rdna Its ◽  
Baermann Technique ◽  
In Captivity ◽  
Second Internal Transcribed Spacer ◽  
Muellerius Capillaris

SummaryProtostrongylids, small nematode lungworms, are an integral part of the wild ruminant helminth community, which can damage animals’ health when they are held in captivity or semi-captive conditions. The Sahelo-Saharan antelope species dorcas gazelle (Gazella dorcas), the scimitar-horned oryx (Oryx dammah), and the addax (Addax nasomacculatus), reintroduced to Souss-Massa National Park in Morocco, could be host to many species of Protostrongylids. This study was conducted from January to July 2015 to identify infecting parasite species, and determine their prevalence and abundance in all three antelope species. A total of 180 individual fecal samples were collected, morphologically examined by the Baermann technique, and molecularly identified by PCR amplification and sequencing of the second internal transcribed spacer region of the rDNA (ITS-2).Two parasite species were found in the three antelope populations: Muellerius capillaris and Neostrongylus linearis. The prevalence scores recorded for M. capillaris were 98.40 % in the addax, 96.70 % in dorcas gazelle, and 28.40 % in the oryx. The prevalence rates of N. linearis were 60 % in the addax, 23.40 % in dorcas gazelle, and 90 % in the oryx. Excreted larvae were quantified by LPG (larvae per gram) counting: for M. capillaris, the LPG mean values were 92.94 in the addax, 133.09 in dorcas gazelle, and 1.48 in the oryx; and for N. linearis, the LPG mean values were 6.02 in the addax, 1.37 in dorcas gazelle, and 32.81 in the oryx. These findings indicate that the three species of antelopes are infected with Muellerius capillaris and Neostrongylus linearis to varying degrees in intensity and prevalence.

scholarly journals Ultrastructure of the adrenal gland of paca (Cuniculus paca, Linnaeus, 1766) in captivity

2021 ◽  
Vol 15 (3) ◽  
pp. 203-208
Author(s):  
Sérgio Pinter Garcia Filho ◽  
Leandro Luis Martins ◽  
Paulo Fernandes Marcusso ◽  
Tais Harumi de Castro Sasahara ◽  
Márcia Rita Fernandes Machado
Keyword(s):  
Electron Microscopy ◽  
Adrenal Gland ◽  
Adrenal Glands ◽  
Comparative Anatomy ◽  
The Body ◽  
Cortical Region ◽  
Lateral Incision ◽  
Transmission Electron ◽  
In Captivity ◽  
Microscopy Techniques

Lowland paca (Cuniculus paca, Linnaeus, 1766) is a medium-sized rodent that belongs to the Brazilian fauna. Yet little information on its morphology is found in the specialized literature. Thus, the objective of the work was to study the morphology of the adrenal gland of paca by means of microscopic ultrastructure analysis. The adrenal gland secretes specialized substances in the body which promote biological functions of great importance and will provide valuable information to studies in comparative anatomy. Two (2) adult lowland pacas were used, male and female. Soon after death, the animals were positioned in the supine position; their abdominal cavities were opened by pre-retro umbilical and lateral incision followed by folding of the abdominal walls to expose the glands. The adrenal glands were removed; fragments were collected, fixed and prepared for ultrastructure observations using scanning electron microscopy and transmission electron microscopy techniques. It was observed that the adrenal glands of the paca have divisions as well as the limits of the cortical and medullary region, as well as the subdivisions of the glomerulosa, fasciculated and reticulated areas of the cortical region as in other rodents. An ultrastructure of cells and their components also showed a lot of similarity to that already demonstrated in different rodents.

Automation of HLA class II genotyping by PCR amplification with sequence-specific primers

1994 ◽  
Vol 39 (2) ◽  
pp. 141
Author(s):  
P. Merel ◽  
F. Comeau ◽  
B. Dupin ◽  
R. Destrebecq ◽  
G. Vezon
Keyword(s):  
Pcr Amplification ◽  
Class Ii ◽  
Hla Class Ii ◽  
Specific Primers

scholarly journals Human oocyte maturation arrest caused by a novel missense mutation in TUBB8

2018 ◽  
Vol 46 (9) ◽  
pp. 3759-3764 ◽  
Author(s):  
Jingjing Xiang ◽  
Wei Wang ◽  
Chunfeng Qian ◽  
Jiangyang Xue ◽  
Ting Wang ◽  
...  
Keyword(s):  
Genetic Testing ◽  
Missense Mutation ◽  
Oocyte Maturation ◽  
Clinical Examination ◽  
Sanger Sequencing ◽  
Mutation Screening ◽  
Pcr Amplification ◽  
Human Oocyte ◽  
Maturation Arrest ◽  
Class Viii

Objective To explore the etiology of human oocyte maturation arrest in two infertile Chinese sisters. Methods Clinical examination and genetic testing of all available family members were conducted, and the findings were used to create a pedigree. Mutation screening using PCR amplification and DNA Sanger sequencing of the entire tubulin beta 8 class VIII gene ( TUBB8) including intron–exon boundaries was performed to identify mutations. Results A novel missense TUBB8 mutation (c.1054G > T, p.A352S) in the patient and her elder sister was detected and shown to be associated with oocyte maturation arrest. Conclusion Our findings expand the known mutation spectrum of TUBB8 and provide insights into the etiology of human oocyte maturation arrest.

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