scholarly journals Breeding of Cav2.3 deficient mice reveals Mendelian inheritance in contrast to complex inheritance in Cav3.2 null mutant breeding

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Anna Papazoglou ◽  
Christina Henseler ◽  
Karl Broich ◽  
Johanna Daubner ◽  
Marco Weiergräber

AbstractHigh voltage-activated Cav2.3 R-type Ca2+ channels and low voltage-activated Cav3.2 T-type Ca2+ channels were reported to be involved in numerous physiological and pathophysiological processes. Many of these findings are based on studies in Cav2.3 and Cav3.2 deficient mice. Recently, it has been proposed that inbreeding of Cav2.3 and Cav3.2 deficient mice exhibits significant deviation from Mendelian inheritance and might be an indication for potential prenatal lethality in these lines. In our study, we analyzed 926 offspring from Cav3.2 breedings and 1142 offspring from Cav2.3 breedings. Our results demonstrate that breeding of Cav2.3 deficient mice shows typical Mendelian inheritance and that there is no indication of prenatal lethality. In contrast, Cav3.2 breeding exhibits a complex inheritance pattern. It might be speculated that the differences in inheritance, particularly for Cav2.3 breeding, are related to other factors, such as genetic specificities of the mutant lines, compensatory mechanisms and altered sperm activity.

2009 ◽  
Vol 129 (8) ◽  
pp. 1511-1517
Author(s):  
Nicodimus Retdian ◽  
Jieting Zhang ◽  
Takahide Sato ◽  
Shigetaka Takagi

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jun Xu ◽  
Xiang Cui ◽  
Huiyuan Zhang

AbstractThe electric eel is a unique species that has evolved three electric organs. Since the 1950s, electric eels have generally been assumed to use these three organs to generate two forms of electric organ discharge (EOD): high-voltage EOD for predation and defense and low-voltage EOD for electrolocation and communication. However, why electric eels evolved three electric organs to generate two forms of EOD and how these three organs work together to generate these two forms of EOD have not been clear until now. Here, we present the third form of independent EOD of electric eels: middle-voltage EOD. We suggest that every form of EOD is generated by one electric organ independently and reveal the typical discharge order of the three electric organs. We also discuss hybrid EODs, which are combinations of these three independent EODs. This new finding indicates that the electric eel discharge behavior and physiology and the evolutionary purpose of the three electric organs are more complex than previously assumed. The purpose of the middle-voltage EOD still requires clarification.


Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1112
Author(s):  
Yu-En Wu ◽  
Jyun-Wei Wang

This study developed a novel, high-efficiency, high step-up DC–DC converter for photovoltaic (PV) systems. The converter can step-up the low output voltage of PV modules to the voltage level of the inverter and is used to feed into the grid. The converter can achieve a high step-up voltage through its architecture consisting of a three-winding coupled inductor common iron core on the low-voltage side and a half-wave voltage doubler circuit on the high-voltage side. The leakage inductance energy generated by the coupling inductor during the conversion process can be recovered by the capacitor on the low-voltage side to reduce the voltage surge on the power switch, which gives the power switch of the circuit a soft-switching effect. In addition, the half-wave voltage doubler circuit on the high-voltage side can recover the leakage inductance energy of the tertiary side and increase the output voltage. The advantages of the circuit are low loss, high efficiency, high conversion ratio, and low component voltage stress. Finally, a 500-W high step-up converter was experimentally tested to verify the feasibility and practicability of the proposed architecture. The results revealed that the highest efficiency of the circuit is 98%.


2021 ◽  
pp. 1-7
Author(s):  
Shota Sakai ◽  
Asami Makino ◽  
Akihito Nishi ◽  
Takeshi Ichikawa ◽  
Tadashi Yamashita ◽  
...  

Sphingomyelin (SM) is a constituent of cellular membranes, while ceramides (Cer) produced from SM on plasma membranes serve as a lipid mediator that regulates cell proliferation, differentiation, and apoptosis. In the skin, SM also is a precursor of Cer, an important constituent of epidermal permeability barrier. We investigated the role of epidermal SM synthase (SMS)2, an isoform of SMS, which modulates SM and Cer levels on plasma membranes. Although SMS2-knockout (SMS2-KO) mice were not neonatal lethal, an ichthyotic phenotype with epidermal hyperplasia and hyperkeratosis was evident at birth, which persisted until 2 weeks of age. These mice showed abnormal lamellar body morphology and secretion, and abnormal extracellular lamellar membranes in the stratum corneum. These abnormalities were no longer evident by 4 weeks of age in SMS2-KO mice. Our study suggests that (1) exposure to a dry terrestrial environment initiates compensatory responses, thereby normalizing epidermal ichthyotic abnormalities and (2) that a nonlethal gene abnormality can cause an ichthyotic skin phenotype.


2021 ◽  
Vol 42 (Supplement_1) ◽  
pp. S130-S131
Author(s):  
Andrew Khalifa ◽  
Anzar Sarfraz ◽  
Jacob B Avraham ◽  
Ronnie Archie ◽  
Matthew Kaminsky ◽  
...  

Abstract Introduction Electrical injuries represent 0.4–3.2% of admissions to burn units and are responsible for >500 deaths per year in the United States. Approximately half occur in the workplace and are the fourth leading cause of work-related-traumatic death. The extent of injury can be drastically underestimated by total body surface area percentage (TBSA). Along with cutaneous burns, high voltage electrical injuries can lead to necrosis of muscle, bone, nervous tissue, and blood vessels. Aggressive management allows for patient survival, but at significant cost. Newer technologic advances help improve functional outcomes. Methods This case-report was conducted via retrospective chart review of the case presented. Results A 43-year-old male sustained a HVEI (>10, 000 V) after contacting an active wire while working as a linesman for an electric company. He presented after less than 15-minute transport from an outside hospital with full thickness burns and auto-amputation to all fingers on both hands and the distal third of the left hand (Images 1 and 2). There were full thickness circumferential burns to the entire left and right upper extremities with contractures, with the burns extending into the axilla, and chest wall musculature. The patient had 4th degree burns and a large wound to the left shoulder with posterior extension to the scapula, flank and back with approximately 25% TBSA (Image 3). Compartments were tense in both upper extremities. Patient was sedated and intubated to protect the airway and placed on mechanical ventilation. A femoral central line was then placed, and the patient was given pain control, continued fluid resuscitation, and blood products. Dark red colored urine from a foley catheter that was immediately identified as rhabdomyolysis induced myoglobinuria. Labs drawn demonstrated elevated troponin I, CK >40,000. BUN 18, creatinine 1.0, K+ 5.2 and phosphate 5.6. Decision was made immediately for operative intervention with emergent amputation of both upper extremities in the light of rhabdomyolysis secondary to tissue necrosis and oliguria. During the patient’s hospital course, he underwent multiple operations for further debridement with vacuum-assisted closure therapy and skin grafting of sites, as well as targeted muscle reinnervation (TMR) 6 months later at an outside hospital. Conclusions Although HVEI only account for a small percentage of burn admissions, they are associated with greater morbidity than low-voltage injuries. Patients with HVEI often incur multiple injuries, more surgical procedures, have higher rates of complications, and more long term psychological and rehabilitative difficulties. Despite the need for amputation in some of these critically ill patients, options exist that allow for them to obtain long term functional success.


Sign in / Sign up

Export Citation Format

Share Document