Variable sperm size and motility activation in the pipefish, Syngnathus abaster; adaptations to paternal care or environmental plasticity?

2008 ◽  
Vol 20 (4) ◽  
pp. 474 ◽  
Author(s):  
B. B. Dzyuba ◽  
K. J. W. Van Look ◽  
V. S. Kholodnyy ◽  
N. Satake ◽  
S. Cheung ◽  
...  
Keyword(s):  
Paternal Care ◽  
Close Contact ◽  
The Body ◽  
Brood Pouch ◽  
Ovarian Fluid ◽  
Sperm Duct ◽  
Sperm Activation ◽  
Egg Ratio ◽  
Sperm Size ◽  
Significant Distance

Like seahorses, some of the closely-related pipefish species (Family Syngnathidae) incubate their eggs within a male brood pouch. This has contributed to considerable confusion about sperm transfer mechanisms to the eggs; some authors have reported that ejaculates are released directly into water before they reach the eggs, while others have suggested that eggs are fertilised using spermatozoa deposited directly into the brood pouch via an internal sperm duct. Here we present anatomical evidence from the freshwater pipefish, Syngnathus abaster, showing not only that direct sperm deposition into the pouch is impossible, but that spermatozoa must somehow travel a significant distance (>4 mm) outside the body of the male, to reach and fertilise eggs in the pouch. We have also used several putative sperm-activating solutions to identify the type of environment most conducive to sperm activation. Spermatozoa released from the testis were active for a brief period (<5 min) in water or 150 mm saline, but showed prolonged (>25 min) motility in ovarian fluid. This suggests that spermatozoa are released into a mixture of ovarian fluid and eggs while the male and female are in close contact. Our data also suggest that the fertilisation mechanism is highly efficient (sperm : egg ratio <200 : 1) even though this pipefish species produces dimorphic spermatozoa (with long and short flagellae). The shorter (<40 μm) morphotypes were not capable of motility activation, and are therefore probably incapable of fertilisation. If so, the sperm : egg ratio reported here would represent an overestimate.

Neuronal Sodium Leak Channel Is Responsible for the Detection of Sodium in the Rat Median Preoptic Nucleus

2011 ◽  
Vol 105 (2) ◽  
pp. 650-660 ◽  
Author(s):  
Christina Tremblay ◽  
Emmanuelle Berret ◽  
Mélaine Henry ◽  
Benjamin Nehmé ◽  
Louis Nadeau ◽  
...  
Keyword(s):  
Close Contact ◽  
Critical Role ◽  
Reversal Potential ◽  
Outward Current ◽  
The Body ◽  
Equilibrium Potential ◽  
Preoptic Nucleus ◽  
Leak Channel ◽  
Median Preoptic Nucleus ◽  
Electrophysiological Recordings

Sodium (Na+) ions are of primary importance for hydromineral and cardiovascular homeostasis, and the level of Na+ in the body fluid compartments [plasma and cerebrospinal fluid (CSF)] is precisely monitored in the hypothalamus. Glial cells seem to play a critical role in the mechanism of Na+ detection. However, the precise role of neurons in the detection of extracellular Na+ concentration ([Na+]out) remains unclear. Here we demonstrate that neurons of the median preoptic nucleus (MnPO), a structure in close contact with the CSF, are specific Na+ sensors. Electrophysiological recordings were performed on dissociated rat MnPO neurons under isotonic [Na+] (100 mM NaCl) with local application of hypernatriuric (150, 180 mM NaCl) or hyponatriuric (50 mM NaCl) external solution. The hyper- and hyponatriuric conditions triggered an in- and an outward current, respectively. The reversal potential of the current matched the equilibrium potential of Na+, indicating that a change in [Na+]out modified the influx of Na+ in the MnPO neurons. The conductance of the Na+ current was not affected by either the membrane potential or the [Na+]out. Moreover, the channel was highly selective for lithium over guanidinium. Together, these data identified the channel as a Na+ leak channel. A high correlation between the electrophysiological recordings and immunofluorescent labeling for the NaX channel in dissociated MnPO neurons strongly supports this channel as a candidate for the Na+ leak channel responsible for the Na+-sensing ability of rat MnPO neurons. The absence of NaX labeling and of a specific current evoked by a change in [Na+]out in mouse MnPO neurons suggests species specificity in the hypothalamus structures participating in central Na+ detection.

Smart Textiles with Biosensing Capabilities

2012 ◽  
Vol 80 ◽  
pp. 129-135 ◽  
Author(s):  
Stéphanie Pasche ◽  
Bastien Schyrr ◽  
Bernard Wenger ◽  
Emmanuel Scolan ◽  
Réal Ischer ◽  
...  
Keyword(s):  
Real Time ◽  
Optical Fibers ◽  
Close Contact ◽  
Biological Fluids ◽  
Wearable Sensors ◽  
Surrounding Medium ◽  
Sol Gel ◽  
The Body ◽  
In Situ Monitoring ◽  
Easy Integration

Real-time, on-body measurement using minimally invasive biosensors opens up new perspectives for diagnosis and disease monitoring. Wearable sensors are placed in close contact with the body, performing analyses in accessible biological fluids (wound exudates, sweat). In this context, a network of biosensing optical fibers woven in textile enables the fabric to measure biological parameters in the surrounding medium. Optical fibers are attractive in view of their flexibility and easy integration for on-body monitoring. Biosensing fibers are obtained by modifying standard optical fibers with a sensitive layer specific to biomarkers. Detection is based on light absorption of the sensing fiber, placing a light source and a detector at both extremities of the fiber. Biosensing optical fibers have been developed for the in situ monitoring of wound healing, measuring pH and the activity of proteases in exudates. Other developments aim at the design of sensing patches based on functionalized, porous sol-gel layers, which can be deposited onto textiles and show optical changes in response to biomarkers. Biosensing textiles present interesting perspectives for innovative healthcare monitoring. Wearable sensors will provide access to new information from the body in real time, to support diagnosis and therapy.

scholarly journals Clinical Approaches of Biomimetic: An Emerging Next Generation Technology

2021 ◽  
Author(s):  
Kirti Rani
Keyword(s):  
Tissue Engineering ◽  
Close Contact ◽  
The Body ◽  
Next Generation ◽  
Biochemical Engineering ◽  
Security Systems ◽  
Material Sciences ◽  
Reported Data ◽  
Generation Technology

Biomimetic is the study of various principles of working mechanisms of naturally occurring phenomena and their further respective integrations in to such a modified advanced mechanized instruments/models of digital or artificial intelligence protocols. Hence, biomimetic has been proposed in last decades for betterment of human mankind for improving security systems by developing various convenient robotic vehicles and devices inspired by natural working phenomenon of plants, animals, birds and insects based on biochemical engineering and nanotechnology. Hence, biomimetic will be considered next generation technology to develop various robotic products in the fields of chemistry, medicine, material sciences, regenerative medicine and tissue engineering medicine, biomedical engineering to treat various diseases and congenital disorders. The characteristics of tissue engineered scaffolds are found to possess multifunctional cellular properties like biocompatibility, biodegradability and favorable mechanized properties when comes in close contact with the body fluids in vivo. This chapter will provide overall overview to the readers for the study based on reported data of developed biomimetic materials and tools exploited for various biomedical applications and tissue engineering applications which further helpful to meet the needs of the medicine and health care industries.

Potential of ICT in India to Cater Pandemics in Healthcare Sector with Special Reference to Covid-19

2020 ◽  
Vol 9 (2) ◽  
pp. 11-17
Author(s):  
Zafar Majeed Rather ◽  
Magray Ajaz Ahmad
Keyword(s):  
Information And Communication Technologies ◽  
Virus Disease ◽  
Close Contact ◽  
Personal Data ◽  
The Body ◽  
Contact Tracing ◽  
Healthcare Sector ◽  
Infected People ◽  
Personal Data Protection ◽  
Corona Virus

Corona virus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome Corona virus 2 (SARS-CoV-2). The disease was first identified in December 2019 in Wuhan, the capital of China’s Hubei province, and has since spread globally, resulting in the ongoing 2019–20 corona virus pandemic. As of 9 June 2020, more than 7.12 million cases have been reported across 187 countries and territories, resulting in more than 406,000 deaths. More than 3.29 million people have recovered. The virus is primarily spread between people during close contact, often via small droplets produced by coughing, sneezing, or talking. The disease has been given official name as COVID-19[1]. Since its outbreak in china, infrared thermometers were used to check the body temperature in order to identify the infected people. Countries like China and Korea started the use of different technologies to detect, track and prevent the spread of this deadly virus. Among the major technologies used are Internet of Things (IoT), Artificial Intelligence (AI) and deep learning. With the invent of 5G technologies, we are able to transfer and process huge amounts of data on a real time basis. Health experts have argued that a key tool at governments’ disposal to contain the COVID-19 outbreak, and which was not around during the 1918 Spanish Flu, is the ability to harness digital technologies to track the spread. At the same time, deployment of contact tracing apps by governments or public health authorities has added to the debate on online privacy and personal data protection. In this research paper, we discuss the potential application of different information and communication technologies (ICT) like IoT, AI and 5G that can help in (i) Monitoring (ii) surveillance (iii) detection and prevention of COVID-19 and enhancing the healthcare to make it future-ready for any such diseases like COVID-19.

‘Eat coffee candy and die’: sex, death and Huli funerals

Sexual Health ◽  
2012 ◽  
Vol 9 (5) ◽  
pp. 497
Author(s):  
Philip Gibbs ◽  
Heather Worth
Keyword(s):  
Hiv Risk ◽  
Health Workers ◽  
Close Contact ◽  
The Body ◽  
Traditional Values ◽  
Traditional Beliefs ◽  
Rapid Social Change ◽  
Hiv Epidemic ◽  
Social And Economic Development ◽  
Depth Interviews

Background: Sex and death have traditionally been linked in Huli culture in the Southern Highlands in Papua New Guinea. Huli regarded that close contact with women could result in men becoming sick or dying. However, there has been rapid social and economic development in the area and Huli traditions are changing. At the same time, HIV prevalence is rising. Methods: Twenty-five semistructured in-depth interviews were carried out with key informants during a study on HIV risk in the Southern Highlands. Interviews were conducted mostly in Tok Pisin. Interviews were transcribed and the data were analysed though thematic coding. Results: Huli people use ‘eating coffee candy’ as a metaphor for engaging in sex at funerals. This is very new and against traditional values, where women attended funerals and men only built the coffins and buried the body. Nowadays, sex occurs at funerals. This change has disturbed older people because it has not only changed the customary meaning of the funeral space, but it has also encouraged the spread of HIV. Huli use the fatalistic expression ‘Eat coffee candy and die,’ to refer to funerals as a space of HIV risk. Conclusion: Huli community and church leaders, and health workers are attempting to deal with the situation by not allowing men to stay at the funeral site overnight, burying the dead on the same day they die and using customary village law to charge men caught having sex at a funeral. However, traditional beliefs and rapid social change in the context of an HIV epidemic need to be taken into account.

scholarly journals Post-ovulatory secretion of pituitary gonadotropins GtH I and GtH II in the rainbow trout (Oncorhynchus mykiss): regulation by steroids and possible role of non-steroidal gonadal factors

1999 ◽  
Vol 163 (1) ◽  
pp. 87-97 ◽  
Author(s):  
J Chyb ◽  
T Mikolajczyk ◽  
B Breton
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Body Cavity ◽  
The Body ◽  
Ovarian Fluid ◽  
Multiple Injections ◽  
Rainbow Trout Oncorhynchus Mykiss

In order to determine the factors of ovarian origin which can modulate the postovulatory secretion of the FSH-like gonadotropin (GtH I) and the LH-like gonadotropin (GtH II), freshly ovulated female rainbow trout were divided into two groups. In the first group the fish were stripped in order to eliminate the eggs and ovarian fluid from the body cavity, while in the second group the eggs were kept in the body cavity. Subsequently, fish from both groups were implanted with testosterone (10 mg/kg), 17beta-estradiol (10 mg/kg) or 17,20beta-ddihydroxy-4-regnen-3-one (17,20betaP) (1 mg/kg) or injected every 2 days with desteroidized ovarian fluid (1.5 ml/kg). The secretion of GtH I dramatically increased in stripped fish, reaching its maximum levels 2 weeks after ovulation. The preservation of eggs in the body cavity led to the suppression of this increase. The profiles of GtH II secretion were opposite to those encountered for GtH I because the increase of GtH II was observed only in unstripped fish. The administration of steroids showed that testosterone is able to inhibit GtH I release and stimulate that of GtH II in stripped fish, having no effect on the release of these gonadotropins in non-stripped animals. 17beta-Estradiol failed to modify GtH I secretion, however it decreased the release of GtH II in fish containing retained eggs in the body cavity. 17,20betaP had a delayed stimulating influence on GtH I release in unstripped fish. Finally, multiple injections of desteroidized ovarian fluid into stripped fish led to a significant decrease of GtH I release and to an increase of GtH II secretion. This study demonstrates that factors, which are present in ovarian fluid, modulate the post-ovulatory secretion of both gonadotropins--their net action is negative on GtH I and positive on GtH II. Among the steroids, testosterone is of major importance, being able to inhibit GtH I release and to stimulate that of GtH II. We also show that non-steroidal factors present in the ovarian fluid can influence the release of both gonadotropins, which indirectly supports the previous findings about the existence of inhibin/activin-like factors in fish.

scholarly journals Convergent evolution of sperm gigantism and the developmental origins of sperm size variability in Caenorhabditis nematodes

2016 ◽  
Author(s):  
Anne Vielle ◽  
Nicolas Callemeyn-Torre ◽  
Clotilde Gimond ◽  
Nausicaa Poullet ◽  
Jeremy C. Gray ◽  
...  
Keyword(s):  
Sperm Competition ◽  
Convergent Evolution ◽  
Paternal Care ◽  
Early Stage ◽  
Size Variation ◽  
Egg Cell ◽  
Evolutionary Origins ◽  
Integrative View ◽  
Size Variability ◽  
Sperm Size

AbstractSperm cells provide crucial, if usually diminutive, ingredients to successful sexual reproduction as the source of centrioles and half the diploid genome. Despite this essential conserved function, sperm competition and coevolution with female traits can drive spectacular change in size and shape of these motile cells. Here we characterize four repeated instances of convergent evolution of sperm gigantism in Caenorhabditis nematodes using phylogenetic comparative methods on 26 species. Species at the extreme end of the 50-fold range of sperm-cell volumes across the genus have sperm capable of comprising up to 5% of egg-cell volume, representing severe attenuation of the magnitude of anisogamy. Exploring potential genetic and developmental determinants of Caenorhabditis sperm size variation, we uncover significant differences in mean and variance of sperm size among genotypes, between sexes of androdioecious species, as well as within and between individuals of identical genotypes. We demonstrate that the developmental basis of sperm size variation, both within and between species, becomes established during an early stage of sperm development, i.e. at the formation of primary spermatocytes while subsequent meiotic divisions contribute little further sperm size variability. These findings provide first insights into the developmental determinants of inter-and intraspecific sperm size differences in Caenorhabditis. Together, our results provide a novel integrative view on the developmental and evolutionary origins of Caenorhabditis sperm size variation. We hypothesize that life history and/or ecological differences among species favoured the evolution of alternative sperm competition strategies toward either many smaller sperm or fewer larger sperm, with gigantic sperm potentially providing a means of paternal care via gametic provisioning or as a potent vehicle for sexual conflict over offspring development.

scholarly journals RECOMMENDATIONS FOR VISITING WATER COMPLEXES DURING COVID-19 PANDEMIC

2021 ◽  
pp. 124-128
Author(s):  
К. V. Solomakha
Keyword(s):  
Water Samples ◽  
Close Contact ◽  
Free Chlorine ◽  
The Body ◽  
Laboratory Research ◽  
Microbial Count ◽  
Swimming Pools ◽  
Water Control ◽  
Fecal Matter ◽  
Pool Water

The coronavirus pandemic has changed the usual way of life of almost every one of us, all areas have shifted to work with limited functioning and activities in quarantine. SARS-CoV-2, the causative agent of COVID-19, is mostly transmitted from person to person by close contact through small droplets (released during coughing, sneezing and talking) contaminated with the virus, or virus particles that linger in the air for several minutes to several hours, less often infection occurs through contaminated surfaces and objects. The objective was to analyze the possibility of safe operation of water complexes (water parks, swimming pools, etc.) during a pandemic COVID-19 in our country. Materials and methods. Since November 2019 and so far, we have been taking water samples from one private pool and from the pool of a sports complex in one University in Kyiv, in addition, because of cooperation with the Brovary Regional Department of Laboratory Research of the State Institution «Kyiv Regional Laboratory Center of the Ministry of Health of Ukraine» we have known the results of water control in one under roof water park in Brovary, which is located in Kyiv region. We explored the quality of water by sanitary chemical indices (odor, color, turbidity, pH, water hardness, concentration of ammonia and ammonium ions, chlorides, sulfates, free chlorine, etc.) and microbiological indicators (total microbial count (TMC) and coli bacterial index (index of bacteria of the group of E. coli (CBI)). Results of the research. In our research, we analyzed the guidelines on the possibility and conditions of the functioning of water complexes during quarantine restrictions of various countries. We found that the free chlorine level in water samples complies to those recommendation, which WHO is provided in the context of the coronavirus pandemic in private and public water complexes. Currently, there are no studies that suggest the possibility of survival of SARS-CoV-2 virus in swimming pool water or other water entertainment complexes, although experimental data obtained previously with coronaviruses (on cell cultures) other than SARS CoV-2, indicate that they are usually sensitive to strong oxidants, such as chlorine. Therefore, today, we can assume that purified water in swimming pools and other water complexes is not an environment where the SARS-CoV-2 virus can survive. The WHO states that a residual free chlorine concentration ≥ 0.5 mg / L in pool water at pH < 8,0 is sufficient to kill coronaviruses. The virus that causes COVID-19 has been found in the fecal matter of infected people, not just those with symptoms of gastrointestinal disorders. It's generally believed that the excretion of the virus may persist for several days. However, it should be noted that there are no cases of fecal-oral transmission of SARS-CoV-2 now. Therefore, to date, the risk of SARS-CoV-2 transmission by fecal-oral route is assessed as low. Conclusions. According to the data from lead countries regarding recommendations for visiting water complexes during the COVID-19 pandemic and because of the lack of our own research in our country, we can talk about the possibility of their implementation in Ukraine. We believe that the constant closure of swimming pools and water complexes, and, consequently, constant breaks in the training of not only professional athletes, but also amateurs, run counter to the recommendations regarding the promotion of a healthy lifestyle. It`s worth to remember that prevention is always better than treatment, and training sports is one of the key points in ensuring the effective work of the body and the immune system in particular, which is especially important during a pandemic.

scholarly journals Modern understanding of pathogenesis of periodontal diseases and prospects of modulation therapy (literature review)

2021 ◽  
Vol 23 (5) ◽  
pp. 730-738
Author(s):  
V. M. Zubachyk ◽  
O. A. Petryshyn ◽  
O. V. Zubachyk
Keyword(s):  
Close Contact ◽  
Periodontal Diseases ◽  
Biological Response ◽  
Pathological Process ◽  
Term Treatment ◽  
The Body ◽  
Periodontal Pathogens ◽  
Treatment And Prevention ◽  
Long Term Treatment ◽  
Effective Drugs

Aim. To study scientific literature which covers the onset and course of major periodontal diseases and possible methods of body modulation for such patients. To analyze the information provided by the modern scientific researches of periodontal diseases pathogenesis and treatment results to outline prospective directions of therapeutic influence on the patient’s organism. Conclusions. The pathogenesis of gingivitis and periodontitis is determined by some factors, the main of which are local, microorganisms in particular, that are counteracted by the immune system. Periodontal tissue is in close contact with the organs and systems of the body. Their diseases significantly affect the course, treatment and prevention of periodontitis. This requires a multifaceted approach and the choice of the most effective drugs. The primary strategy of preventing gingivitis is to eliminate the attachment of periodontal pathogens to the epithelium and surface of the teeth to prevent the penetration of microorganisms and their toxins through natural protective barriers. It is more important to resort to biological approaches using probiotics, as well as other natural media in order to prevent dysbiosis, long-term treatment, and maintenance therapy. The concept of vaccination against periodontitis is now being elaborated. Correction of the pathological process in the periodontium is considered in the context of the overall biological response of the organism. Therefore, the assessment of the role of its regulators reveals not only the features of local mechanisms, modulation pathways, but also the choice of effective drugs. Prospects of new approaches and introduction of highly effective drugs are critically analyzed.

Prevention of injuries in sports

2021 ◽  
pp. 46-48
Author(s):  
Anatoliy Denisovets ◽  
Pavlo Pylypchuk
Keyword(s):  
Sports Injuries ◽  
Bone Fractures ◽  
Close Contact ◽  
The Body ◽  
Basketball Players ◽  
Severe Injuries ◽  
Tennis Players ◽  
Chest Injuries ◽  
Limb Injuries ◽  
Rupture Of The Bladder

Purpose: to determine the causes of injuries in sports and the factors that cause them. Material and methods: study of special literature and generalization of experience of preparation of sportsmen in various kinds of sports. Analysis of factors influencing sports injuries in order to develop measures for their prevention. Results: There are a large number of injuries that can be received during sports. In our article we will consider some of them. Trauma is a lesion of the surface of the body or internal organs, which arose under the influence of external factors, as a result of which one or another organ has lost the ability to perform its function. Depending on the nature of the injured tissue, there are skin (strokes, wounds), subcutaneous (ligament ruptures, bone fractures, etc.) and abdominal (hemorrhage, chest injuries, joints) injuries. Injuries are divided into direct and indirect, depending on the point of application of force. They can be single (eg, transverse femoral fracture), multiple (multiple rib fracture), combined (pelvic fracture with rupture of the bladder) and combined (hip fracture and frostbite, etc.). Injuries are open with a violation of integrity and closed, when the replacement of tissues and organs occurs with intact skin and mucous membranes. According to the level of severity of injuries are divided into mild, moderate and severe. Injuries to the extremities are most often observed in the localization of injuries in athletes, among them injuries of the joints, especially the knee and ankle, predominate. Upper limb injuries (70.0% of all injuries) are more common during gymnastics. Most sports are characterized by injuries of the lower extremities, such as athletics and skiing (66,0 %). Head and face injuries are typical for boxers (65,0 %), fingers - for basketball players and volleyball players (80,0 %), elbow joint for tennis players (70,0 %), knee joint - for football players (48,0 %). etc. Among sports injuries, as a rule, a high percentage of injuries of medium severity. Conclusion: analysis of the causes of injuries in sports, allows us to conclude that injuries in sports can be prevented. A coach in a certain sport plays a crucial role in injury prevention. Its activities should take place in close contact with medical staff. It is the physician's responsibility to systematically record all injuries. Not only severe injuries, but also moderate injuries must be carefully studied, the causes of their occurrence must be identified and the necessary measures to eliminate them must be developed.

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