In vivo male african catfish sperm obtaining and evaluation for artificial reproduction

2021 ◽  
pp. 32-41
Author(s):  
Galina Iozepovna Pronina ◽  
Alexey Alexandrovich Panteleev ◽  
Elena E. Susova
Keyword(s):  
Abdominal Cavity ◽  
Optimal Dose ◽  
Abdominal Muscles ◽  
African Catfish ◽  
Clove Oil ◽  
Artificial Reproduction ◽  
High Quality ◽  
Hormonal Stimulation ◽  
Antiseptic Solution

African catfish is a valuable unpretentious object of breeding. It is successfully grown in re-circulating aquaculture systems in mild climate areas. However, artificial reproduction of the African catfish has problems with the collecting of high-quality sperm for fertilization of eggs. Abdominal massage does not give results even after appropriate hormonal stimulation: sperm is released in a small volume, often with an admixture of urine and blood. At the same time, most spermatozoa are motionless. This is due to the morphological features of the gonad structure: the seminal tubules are of the percoid type, in which there are seminal vesicles that prevent sperm release. When breeding catfish, the method of slaughtering males is mainly used, followed by the extraction of gonads, their grinding and straining through gauze or a sieve. Therefore, an urgent task is to develop methods for in vivo male African catfish high-quality sperm collecting. This report shows the technique of gonadectomy and surgery techniques for extracting one or both gonads. General anesthesia was performed by immersing the fish in a solution of clove oil. The optimal dose of clove oil for anesthesia was determined as 0.10–0.20 ml/l. The surgical area was treated with an antiseptic solution. The skin was dissected and separated from abdominal muscles. After acutorsion of testicular vessels, the gonad was excised entirely, since with partial resection, the remaining part of the parenchyma oozes, causing inflammation of the abdominal cavity and impaired healing of the surgical wound. Intermittent octal sutures were applied separately to the peritoneum with abdominal muscles and skin to create additional anastomoses and prevent complications.

Improving the technology of reproduction of channel catfish Ictalurus punctatus (Raf.) in the conditions of warm-water fisheries

2020 ◽  
pp. 34-43
Author(s):  
Ludmila Ivanovna Zakonnova ◽  
Igor Vasilievich Nikishkin
Keyword(s):  
Total Dose ◽  
Ictalurus Punctatus ◽  
Channel Catfish ◽  
Artificial Reproduction ◽  
High Quality ◽  
Maturation Period ◽  
Hormonal Stimulation ◽  
Injection Scheme ◽  
Fish Industry ◽  
Stimulation Of

In the process of work on the reproduction of the channel catfish Ictalurus punctatus (Raf.) In the conditions of LLC «Belovsky Fish Industry», the main problem was the timely production of high-quality offspring, associated with differences in preparation for spawning of females and males. In this regard, the purpose of the work: to develop and test various options for carrying out spawning campaigns, including those using various drugs for hormonal stimulation of manufacturers. The results of testing Nerestin preparations in 2006–2008 are presented. In 2006, the drug Nerestin-5x (N5x) was tested. The main problem was identified: 80% of the injected females matured, but the passive males did not start fertilization. It was proposed to adjust the total dose of H5x for females towards a decrease, depending on the degree of their initial readiness, and for males — towards an increase. In 2007, drugs H5x and H7A were tested. A change in the injection scheme of males in 2007 compared to 2006 (an increase in the total dose to the norm of females, but with the use of the drug H5x, and not H6A or H7A during the first two injections) increased the readiness of males for spawning slightly. In 2008, males were brought into the hatchery one month earlier than females, increasing the maturation period of males and changing the temperature rise schedule to prepare for spawning. The drug H7A was used. Despite the increase in the total dose of H7A for males to the total dose for females, their readiness for spawning was still insufficient. To a greater extent, the readiness of males was influenced by an increase in the period of keeping and feeding. The conclusion is drawn that preparations H7 and H7A are quite applicable for artificial reproduction of channel catfish, but the technique of application must be improved by adjusting the conditions of pre-spawning maintenance of producers and the injection scheme.

scholarly journals Optimization of X-ray Investigations in Dentistry Using Optical Coherence Tomography

Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4554
Author(s):  
Ralph-Alexandru Erdelyi ◽  
Virgil-Florin Duma ◽  
Cosmin Sinescu ◽  
George Mihai Dobre ◽  
Adrian Bradu ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Radiation Dose ◽  
Imaging Techniques ◽  
Image Resolution ◽  
Optical Coherence ◽  
X Rays ◽  
High Quality ◽  
X Ray

The most common imaging technique for dental diagnoses and treatment monitoring is X-ray imaging, which evolved from the first intraoral radiographs to high-quality three-dimensional (3D) Cone Beam Computed Tomography (CBCT). Other imaging techniques have shown potential, such as Optical Coherence Tomography (OCT). We have recently reported on the boundaries of these two types of techniques, regarding. the dental fields where each one is more appropriate or where they should be both used. The aim of the present study is to explore the unique capabilities of the OCT technique to optimize X-ray units imaging (i.e., in terms of image resolution, radiation dose, or contrast). Two types of commercially available and widely used X-ray units are considered. To adjust their parameters, a protocol is developed to employ OCT images of dental conditions that are documented on high (i.e., less than 10 μm) resolution OCT images (both B-scans/cross sections and 3D reconstructions) but are hardly identified on the 200 to 75 μm resolution panoramic or CBCT radiographs. The optimized calibration of the X-ray unit includes choosing appropriate values for the anode voltage and current intensity of the X-ray tube, as well as the patient’s positioning, in order to reach the highest possible X-rays resolution at a radiation dose that is safe for the patient. The optimization protocol is developed in vitro on OCT images of extracted teeth and is further applied in vivo for each type of dental investigation. Optimized radiographic results are compared with un-optimized previously performed radiographs. Also, we show that OCT can permit a rigorous comparison between two (types of) X-ray units. In conclusion, high-quality dental images are possible using low radiation doses if an optimized protocol, developed using OCT, is applied for each type of dental investigation. Also, there are situations when the X-ray technology has drawbacks for dental diagnosis or treatment assessment. In such situations, OCT proves capable to provide qualitative images.

scholarly journals Visceral pressure stimulator for exploring hollow organ pain: a pilot study

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Michael DeLong ◽  
Mauricio Gil-Silva ◽  
Veronica Minsu Hong ◽  
Olivia Babyok ◽  
Benedict J. Kolber
Keyword(s):  
Visceral Pain ◽  
Bladder Pressure ◽  
Abdominal Muscles ◽  
Analog To Digital ◽  
In Vivo Experiments ◽  
Digital Pressure ◽  
Hollow Organ ◽  
Specialized Hardware ◽  
And Control

Abstract Background The regulation and control of pressure stimuli is useful for many studies of pain and nociception especially those in the visceral pain field. In many in vivo experiments, distinct air and liquid stimuli at varying pressures are delivered to hollow organs such as the bladder, vagina, and colon. These stimuli are coupled with behavioral, molecular, or physiological read-outs of the response to the stimulus. Care must be taken to deliver precise timed stimuli during experimentation. For example, stimuli signals can be used online to precisely time-lock the stimulus with a physiological output. Such precision requires the development of specialized hardware to control the stimulus (e.g., air) while providing a precise read-out of pressure and stimulus signal markers. Methods In this study, we designed a timed pressure regulator [termed visceral pressure stimulator (VPS)] to control air flow, measure pressure (in mmHg), and send stimuli markers to online software. The device was built using a simple circuit and primarily off-the-shelf parts. A separate custom inline analog-to-digital pressure converter was used to validate the real pressure output of the VPS. Results Using commercial physiological software (Spike2, CED), we were able to measure mouse bladder pressure continuously during delivery of unique air stimulus trials in a mouse while simultaneously recording an electromyogram (EMG) of the overlying abdominal muscles. Conclusions This device will be useful for those who need to (1) deliver distinct pressure stimuli while (2) measuring the pressure in real-time and (3) monitoring stimulus on–off using physiological software.

Cortical reaction as an egg quality indicator in artificial reproduction of pikeperch, Sander lucioperca

2012 ◽  
Vol 24 (6) ◽  
pp. 843 ◽  
Author(s):  
Daniel Żarski ◽  
Sławomir Krejszeff ◽  
Katarzyna Palińska ◽  
Katarzyna Targońska ◽  
Krzysztof Kupren ◽  
...  
Keyword(s):  
Quality Evaluation ◽  
Egg Quality ◽  
Effect Of Temperature ◽  
Artificial Reproduction ◽  
Female Fish ◽  
Sander Lucioperca ◽  
Embryo Survival ◽  
Hormonal Stimulation ◽  
Cortical Reaction

The aim of this study was to investigate the process of the cortical reaction in eggs of pikeperch, Sander lucioperca (L.), as well as the application of microscopic assessment of this process in egg quality evaluation. The analysis was carried out with eggs obtained from 10 females by artificial reproduction, in which hormonal stimulation with hCG was applied. Subsequently, each sample of eggs (separately from each female fish) was analysed. The analysis included observation of the cortical reaction and the process of egg swelling, and determination of the effect of temperature (12, 14 and 16°C) and the presence of spermatozoa on the cortical reaction. The results indicate that the cortical reaction in pikeperch eggs is quite violent, resulting in visible deformation of eggs between 3 and 5 min after activation. No effect of temperature or the presence of spermatozoa on the cortical reaction was observed. A strong correlation was recorded for the percentage of egg deformations observed and embryo survival rate. The described method of determination of pikeperch egg quality (based on egg deformation rate between 3 and 5 min after activation) may be highly useful, both in scientific research (where high-quality eggs are required) and in hatchery practice.

scholarly journals A Dynamic Culture Method to Produce Ovarian Cancer Spheroids under Physiologically-Relevant Shear Stress

Cells ◽  
2018 ◽  
Vol 7 (12) ◽  
pp. 277 ◽  
Author(s):  
Timothy Masiello ◽  
Atul Dhall ◽  
L. Hemachandra ◽  
Natalya Tokranova ◽  
J. Melendez ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Shear Stress ◽  
Fluid Shear Stress ◽  
Abdominal Cavity ◽  
Culture Method ◽  
Experimental Conditions ◽  
Dynamic Cell ◽  
Screening Platform ◽  
Cancer Spheroids

The transcoelomic metastasis pathway is an alternative to traditional lymphatic/hematogenic metastasis. It is most frequently observed in ovarian cancer, though it has been documented in colon and gastric cancers as well. In transcoelomic metastasis, primary tumor cells are released into the abdominal cavity and form cell aggregates known as spheroids. These spheroids travel through the peritoneal fluid and implant at secondary sites, leading to the formation of new tumor lesions in the peritoneal lining and the organs in the cavity. Models of this process that incorporate the fluid shear stress (FSS) experienced by these spheroids are few, and most have not been fully characterized. Proposed herein is the adaption of a known dynamic cell culture system, the orbital shaker, to create an environment with physiologically-relevant FSS for spheroid formation. Experimental conditions (rotation speed, well size and cell density) were optimized to achieve physiologically-relevant FSS while facilitating the formation of spheroids that are also of a physiologically-relevant size. The FSS improves the roundness and size consistency of spheroids versus equivalent static methods and are even comparable to established high-throughput arrays, while maintaining nearly equivalent viability. This effect was seen in both highly metastatic and modestly metastatic cell lines. The spheroids generated using this technique were fully amenable to functional assays and will allow for better characterization of FSS’s effects on metastatic behavior and serve as a drug screening platform. This model can also be built upon in the future by adding more aspects of the peritoneal microenvironment, further enhancing its in vivo relevance.

scholarly journals Using diffusion MRI data acquired with ultra-high gradients to improve tractography in routine-quality data

2021 ◽  
Author(s):  
Chiara Maffei ◽  
Christine Lee ◽  
Michael Planich ◽  
Manisha Ramprasad ◽  
Nivedita Ravi ◽  
...  
Keyword(s):  
Diffusion Mri ◽  
Region Of Interest ◽  
Training Data ◽  
Quality Data ◽  
High Quality ◽  
Scanning Time ◽  
Human Connectome Project ◽  
High Gradients ◽  
Comprehensive Comparison

The development of scanners with ultra-high gradients, spearheaded by the Human Connectome Project, has led to dramatic improvements in the spatial, angular, and diffusion resolution that is feasible for in vivo diffusion MRI acquisitions. The improved quality of the data can be exploited to achieve higher accuracy in the inference of both microstructural and macrostructural anatomy. However, such high-quality data can only be acquired on a handful of Connectom MRI scanners worldwide, while remaining prohibitive in clinical settings because of the constraints imposed by hardware and scanning time. In this study, we first update the classical protocols for tractography-based, manual annotation of major white-matter pathways, to adapt them to the much greater volume and variability of the streamlines that can be produced from today's state-of-the-art diffusion MRI data. We then use these protocols to annotate 42 major pathways manually in data from a Connectom scanner. Finally, we show that, when we use these manually annotated pathways as training data for global probabilistic tractography with anatomical neighborhood priors, we can perform highly accurate, automated reconstruction of the same pathways in much lower-quality, more widely available diffusion MRI data. The outcomes of this work include both a new, comprehensive atlas of WM pathways from Connectom data, and an updated version of our tractography toolbox, TRActs Constrained by UnderLying Anatomy (TRACULA), which is trained on data from this atlas. Both the atlas and TRACULA are distributed publicly as part of FreeSurfer. We present the first comprehensive comparison of TRACULA to the more conventional, multi-region-of-interest approach to automated tractography, and the first demonstration of training TRACULA on high-quality, Connectom data to benefit studies that use more modest acquisition protocols.

scholarly journals Investigating the Intrafollicular Factors Affecting Oocyte Developmental Competency

2021 ◽  
Author(s):  
◽  
Zaramasina Clark
Keyword(s):  
Gene Expression ◽  
Oocyte Maturation ◽  
Granulosa Cells ◽  
Embryo Quality ◽  
Cumulus Cells ◽  
Significant Finding ◽  
High Quality ◽  
Final Maturation

<p>The number of cycles of assisted reproductive technologies (ART) performed increased by ~9.5 % globally between 2008 and 2010. In spite of this, the success rate in terms of delivery was only ~19.0 % (Dyer et al., 2016). This discrepancy between the demand for, and success of, these technologies necessitates the development of tools to improve ART efficiency. To facilitate this, a better understanding of how the microenvironment changes within the developing follicle to culminate in a mature, developmentally-competent oocyte is required. This study employed an in vivo and in vitro ovine model to investigate the relationship between the surrounding microenvironment and oocyte maturation, and in particular, the attainment of oocyte developmental competency and high-quality embryos.  The first objective of this PhD study was to comprehensively investigate the changing microenvironment of in vivo matured, presumptive preovulatory (PPOV) follicles from wild-type (++) and high ovulation rate (OR; I+B+) ewes. The high OR ewes were heterozygous carriers of mutations in BMP15 (I+) and BMPRIB (B+). Functional differences in follicular somatic (granulosa and cumulus) cells between these genotypes, including differential gonadotropin responsiveness of granulosa cells, composition of follicular fluid and gene expression profiles in cumulus cells were evident. These differences emerged as part of a compensatory mechanism by which oocytes from smaller follicles, containing fewer granulosa cells, achieved developmental competency in I+B+ ewes.  The second objective of this PhD study was to develop new approaches for improving current in vitro maturation (IVM) strategies. The first approach utilised in this study focused on developing biomarkers that could be used to improve prediction of developmental competency in oocytes and in vitro produced embryos. This involved interrogating the hypothesis that a combination of molecular and morphokinetic biomarkers would better predict the developmental competency of oocytes and embryos compared to using these biomarkers alone. The second approach utilised in this PhD study tested the effects of modulating IVM conditions to better mimic the follicular microenvironment of a high, compared to a low, OR species on oocyte developmental competency and embryo quality. This involved supplementing IVM media with different ratios of two oocyte-secreted growth factors, i.e. GDF9:BMP15, that were representative of low or high OR species. These approaches demonstrated significant potential and warrant further investigation.  The most significant finding of this study was that despite variances in the surrounding microenvironment during in vivo and in vitro oocyte maturation that culminated in differential gene expression patterns in cumulus cells, and divergent gonadotropin-responsiveness of granulosa cells, the gene expression signatures of developmentally-competent oocytes and the morphokinetics of high-quality embryos were unaltered. This confirms the value of developing such biomarkers for oocyte development competency and embryo quality that remain unaltered despite a changing surrounding environment. Interestingly, simulating the ratio of GDF9:BMP15 that oocytes from high OR species are exposed to during maturation improved developmental competency in oocytes as demonstrated by increased blastocyst rates. Furthermore, this study has demonstrated that combinations of molecular (cumulus cell gene expression) and morphokinetic biomarkers improved the ability to predict developmental competency in oocytes and embryos. Overall, this study revealed novel information regarding the follicular microenvironment during final maturation and identified several novel approaches to improving the efficiency of ART.</p>

scholarly journals The HROC-Xenobank—A High Quality Assured PDX Biobank of >100 Individual Colorectal Cancer Models

Cancers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 5882
Author(s):  
Stephanie Matschos ◽  
Florian Bürtin ◽  
Said Kdimati ◽  
Mandy Radefeldt ◽  
Susann Krake ◽  
...  
Keyword(s):  
Gene Expression Analysis ◽  
Tumor Tissue ◽  
Hot Spot ◽  
In Vivo Studies ◽  
Cooperative Research ◽  
High Quality ◽  
Current Time ◽  
Cancer Models ◽  
Low Passage

Based on our research group’s large biobank of colorectal cancers (CRC), we here describe the ongoing activity of establishing a high quality assured PDX biobank for more than 100 individual CRC cases. This includes sufficient numbers of vitally frozen (n > 30 aliquots) and snap frozen (n > 5) backups, “ready to use”. Additionally, PDX tumor pieces were paraffin embedded. At the current time, we have completed 125 cases. This resource allows histopathological examinations, molecular characterizations, and gene expression analysis. Due to its size, different issues of interest can be addressed. Most importantly, the application of low-passage, cryopreserved, and well-characterized PDX for in vivo studies guarantees the reliability of results due to the largely preserved tumor microenvironment. All cases described were molecularly subtyped and genetic identity, in comparison to the original tumor tissue, was confirmed by fingerprint analysis. The latter excludes ambiguity errors between the PDX and the original patient tumor. A cancer hot spot mutation analysis was performed for n = 113 of the 125 cases entities. All relevant CRC molecular subtypes identified so far are represented in the Hansestadt Rostock CRC (HROC)-Xenobank. Notably, all models are available for cooperative research approaches.

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