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FASEB BioAdvances Feb 2023Excitability and contraction of cardiac muscle from brain-dead donors critically influence the success of heart transplantation. Membrane physiology, Ca-handling, and...
Excitability and contraction of cardiac muscle from brain-dead donors critically influence the success of heart transplantation. Membrane physiology, Ca-handling, and force production of cardiac muscle and the contractile properties of coronary arteries were studied in hearts of brain-dead pigs. Cardiac muscle and vascular function after 12 h brain death (decapitation between C2 and C3) were compared with properties of fresh tissue. In both isolated cardiomyocytes (whole-cell patch clamp) and trabecular muscle (conventional microelectrodes), action potential duration was shorter in brain dead, compared to controls. Cellular shortening and Ca transients were attenuated in the brain dead, and linked to lower mRNA expression of L-type calcium channels and a slightly lower I,, current, as well as to a lower expression of phospholamban. The current-voltage relationship and the current above the equilibrium potential of the inward K (I) channel were altered in the brain-dead group, associated with lower mRNA expression of the Kir2.2 channel. Delayed K currents were detected (I, I) and were not different between groups. The transient outward K current (I) was not observed in the pig heart. Coronary arteries exhibited increased contractility and sensitivity to the thromboxane analogue (U46619), and unaltered endothelial relaxation. In conclusion, brain death involves changes in cardiac cellular excitation which might lower contractility after transplantation. Changes in the inward rectifier K channel can be associated with an increased risk for arrhythmia. Increased reactivity of coronary arteries may lead to increased risk of vascular spasm, although endothelial relaxant function was well preserved.
PubMed: 36816513
DOI: 10.1096/fba.2022-00104 -
Frontiers in Plant Science 2021Temperate deciduous fruit trees survive winter temperatures by entering a dormant phase in their aerial meristematic organs. Release from bud dormancy occurs after chill...
Temperate deciduous fruit trees survive winter temperatures by entering a dormant phase in their aerial meristematic organs. Release from bud dormancy occurs after chill requirements (CR) have been satisfied, whereas bud burst/flowering follows heat requirement (HR) fulfillment. The physiological basis behind these metrics remains elusive. In this study, we are presenting the first multidisciplinary dormancy progression analysis in northern Patagonia, linking (1) forcing/field phenology, (2) bud anatomical development, and (3) soluble sugar (sucrose, glucose, and fructose) dynamics in L. CR and HR were determined for 'Chandler' and 'Franquette,' two walnut cultivars with markedly different CR, in artificial chill/forced heat trials (three seasons) and in-field chill/forced heat tests (five seasons) using excised twigs either with or without apical buds (non-decapitated and decapitated). The soluble sugar dynamics of 'Chandler' (high-performance liquid chromatography) and the anatomical changes of the buds (light microscopy) of the two cultivars were analyzed during endo-ecodormancy progression in one and two seasons, respectively. The CR defined by artificial chill tests proved to be an overestimation compared to the field determinations. Moreover, HR was the main driver in the phenology dynamics, as expected for a high-chill region. 'Chandler' showed an average of 10.3 field chill portions (CP) and 2,163 Growing Degree Hours (GDH°C) less than 'Franquette' for dormancy release and bud burst, respectively. These results were consistent with the transition of the shoot apex from the vegetative to the reproductive phase and the soluble sugar profile. The decrease in sucrose between 15 and 30 days after CR fulfillment could be a reliable biological marker for endodormancy release in walnut, while the increase in fructose and glucose is likely an osmolyte and cellulosic carbon source in pre-sprouting. In addition, we discuss the effect of paradormancy thanks to our apical bud experiment (with or without). Our results improve the current understanding of endo-ecodormancy progression in walnut and provide insightful results for walnut production (i.e., cultivation practices such as pruning) as well as for further application in dormancy modeling, to infer the ideotypes that should be bred for future climate conditions.
PubMed: 35185955
DOI: 10.3389/fpls.2021.803878 -
The International Journal of... Dec 2023Formaldehyde is a chemical that lies behind the various systemical failures in organism. Many products that people use contain formaldehyde. Owing to its tissue fixative...
AIM
Formaldehyde is a chemical that lies behind the various systemical failures in organism. Many products that people use contain formaldehyde. Owing to its tissue fixative properties, scientists who work in life sciences are exposed to this substance more than others. Several studies have shown that formaldehyde affects the CA1 and CA3 regions of the hippocampus, which play crucial roles in memory consolidation. In this study, we aimed to investigate anxiety levels and indicate the short and long term effects of formaldehyde and sex-related differences by exposing formaldehyde to male and female rats.
MATERIALS AND METHODS
Formaldehyde (10 mg/kg) was administered intraperitoneally for 7 days for acute exposure and 30 days for chronic exposure. Cognitive assessment was performed using fear conditioning, elevated plus maze, and Morris water maze tests. TUNEL staining was used to identify apoptosis in the brains obtained after decapitation.
RESULTS
Exposure to intraperitoneal formaldehyde does not impair learning and memory in acute and chronic periods and has no effect on depression or anxiety. After acute exposure, apoptosis was observed in the hippocampal CA1 and CA3 regions in males. When the cognitive test results were examined, no differences were found between the experimental and control groups. There was also no significant difference between males and females.
PubMed: 38152865
DOI: 10.1080/00207454.2023.2300728 -
ACS Applied Materials & Interfaces Nov 2022Microwave-absorbing materials with wide bandwidth and high absorptivity are increasingly playing an important role in over-the-air (OTA) testing. In this work, a kind of...
Microwave-absorbing materials with wide bandwidth and high absorptivity are increasingly playing an important role in over-the-air (OTA) testing. In this work, a kind of pyramid absorbing material was prepared using flame-retardant absorbers as the filler. In addition, a coating was used to further improve the flame-retardant properties of the microwave-absorbing material. To obtain excellent microwave absorption performance (MWAP), a high-frequency structure simulator (HFSS) was adopted to design structural materials. Here, the total height, the base height, the decapitation height of the pyramid tip, the distance between the pyramids, and other parameters were analyzed; then, the actual processing and molding were realized. The MWAP of -30 dB was achieved at 2.7-18 GHz, and the MWAP of -10 dB was also met at 2-18 GHz. In particular, the study also investigated the MWAP of large angle, which can meet the MWAP of -10 dB at 2-18 GHz and MWAP of -30 dB at 4-18 GHz. Most importantly, the absorption mechanism of the pyramid structure was explored. The influence of the tip was proved by the distribution of the electromagnetic field in the pyramid. It can be regarded as a multilayer microwave-absorbing material due to the impedance gradient of the pyramid, which can provide an effective research idea and method for future engineering applications.
PubMed: 36347823
DOI: 10.1021/acsami.2c16166 -
Journal of Forensic and Legal Medicine Jul 2019Decapitation resulting by vehicle-assisted ligature strangulation is a suicide method rarely described in the literature. The lesions observed at autopsy have a common... (Review)
Review
Decapitation resulting by vehicle-assisted ligature strangulation is a suicide method rarely described in the literature. The lesions observed at autopsy have a common morphology with to those found in post-hanging decapitation. They depend on the force applied by the acceleration of the vehicle, the slope of the road and the characteristics of the link used. They can also mimic a stabbing homicide. We report the case of a 43-year-old man who used a long steel rope, attached between his neck and a streetlight, and started his vehicle, causing a complete decapitation. The results of the autopsy provided information on the morphology of the cervical lesions, but also on the causes of death. In spite of decapitation, the histological examination of the organs confirmed the presence of asphyxiation process by a mechanical origin that occurred before decapitation.
Topics: Adult; Asphyxia; Automobiles; Decapitation; Forensic Pathology; Humans; Male; Suicide
PubMed: 31146145
DOI: 10.1016/j.jflm.2019.05.015 -
Molecular Neurobiology Dec 2023Depressive disorder is a severe and complex mental illness. There are a few anti-depressive medications that can reduce depressive symptoms, but with adverse or side...
Depressive disorder is a severe and complex mental illness. There are a few anti-depressive medications that can reduce depressive symptoms, but with adverse or side effects. GaoYou-13 (GY-13), commonly known as Areca Thirteen Pill, is a traditional medicine for depression treatment with significant clinical impact. However, the molecular mechanism of GY-13 has not been fully elucidated. This study aimed to explore and explain the action and mechanism of GY-13 in treatment for depression. SD male rats were stimulated differently daily for 42 days to construct a depression rat model and divided into six groups: the control, CUMS model, GY-13L, GY-13 M, GY-13H, and FLUO. The body weight of was measured on day 7, 14, 21, 28, 35, and 42 or different days, and the behavioral tests (Open-field test, Sucrose preference test, Morris water maze) were made alongside. After the rats were decapitated, the rat brains were stained with Nissl or H&E dyes. The serums of TNF-α and IL-1β were tested. The protein of p-IKKα, p-IкBα, and p-NFкBp65 was traced. Then nano-LC-MS/MS analysis was made to detect the mechanism of GY-13. The active ingredients, drug targets, and key pathways of GY-13 in treating depression were analyzed through network pharmacology and molecular docking. With immunohistochemistry, quantitative RT-PCR, and western-blot techniques, the therapeutic mechanism of GY-13 was traced and analyzed. This study revealed that GY-13 significantly enhances autonomous and exploratory behavior, sucrose consumption, learning and memory ability, and hippocampal neuronal degeneration, which inhibits inflammation. In addition, omics analysis showed several proteins were altered in the hippocampus of rats following CUMS and GY-13 treatment. Bioinformatics analysis and network pharmacology revealed the antidepressant effects of GY-13 are related to the chemokine/chemokine receptor axis. Immunohistochemistry, western blotting and RT-PCR assay further support the findings of omics analysis. We highlighted the importance of the chemokine/chemokine receptor axis in the treatment of depression, as well as showed GY-13 can be used as a novel targeted therapy for depression treatment.
PubMed: 38110645
DOI: 10.1007/s12035-023-03855-1 -
Scientific Reports Feb 2022Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway is important in the process of inflammation and fibrosis. The adenosine...
Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway is important in the process of inflammation and fibrosis. The adenosine 5'-monophosphate-activated protein kinase (AMPK) enzyme can affect JAK/STAT pathway. Tofacitinib is a pan-JAK inhibitör. Metformin activates AMPK enzyme. We aimed to investigate the therapeutic efficacy of tofacitinib and metformin on IL-17 and TGF-β cytokines, skin fibrosis and inflammation in mouse model of systemic sclerosis (SSc). 40 Balb/c female mice were divided into 4 groups: (control, sham (BLM), tofacitinib and metformin). The mice in the tofacitinib group received oral tofacitinib (20 mg/kg/daily) and mice in the metformin group received oral metformin (50 mg/kg/day) for 28 days. At the end of 4th week, all groups of mice were decapitated and tissue samples were taken for analysis. Histopathological analysis of skin tissue was performed, and mRNA expressions of collagen 3A, IL-17 and TGF-β were assessed by real-time PCR and ELISA. Repeated BLM injections had induced dermal fibrosis. Moreover, the tissue levels of collagen 3A, IL-17 and TGF-β were elevated in the BLM group. Tofacitinib and metformin mitigated dermal fibrosis. They reduced dermal thickness and tissue collagen 3A, IL-17 and TGF-β levels. Tofacitinib and metformin demonstrated anti-inflammatory and anti-fibrotic effects in the mouse model of SSc.
Topics: Animals; Drug Therapy, Combination; Female; Fibrosis; Metformin; Mice; Mice, Inbred BALB C; Piperidines; Pyrimidines; Scleroderma, Systemic; Skin
PubMed: 35169250
DOI: 10.1038/s41598-022-06581-1 -
Cureus Jan 2023Since the development of the infamous guillotine in the French Revolution, physicians have debated how long consciousness persists in decapitated heads. Fueled by... (Review)
Review
Since the development of the infamous guillotine in the French Revolution, physicians have debated how long consciousness persists in decapitated heads. Fueled by anecdotes of severed heads that blink, blush, and appear to retain intelligence, numerous experiments have investigated this macabre subject for nearly 250 years. In this paper, we examine the evidence, both historical and modern, and ultimately conclude that, while the truth may never be fully known, all evidence appears to indicate that loss of consciousness appears to occur within seconds of decapitation. The rumors that circulated through the European consciousness during the Terror of the French Revolution appear to be just that - curious urban legends from an awed and terrified public.
PubMed: 36819446
DOI: 10.7759/cureus.33830 -
Radiography (London, England : 1995) Oct 2023The porcine model shows structural features comparable to that of humans and are routinely used within research, due to the ethical, legal, and practical use of...
INTRODUCTION
The porcine model shows structural features comparable to that of humans and are routinely used within research, due to the ethical, legal, and practical use of post-mortem human samples. Methods for obtaining high quality and comparable reference data using standardised acquisition protocols are essential.
METHODS
The decapitated heads of three adult white sows were subjected to radiographic imaging before and after cranial trauma (9 mm, Heckler and Koch MP5). Digital radiographs were generated using a Siemens MULTIX TOP system with an Agfa digital detector, with foam blocks and sandbags as ancillary equipment. An iterative approach was adopted by the authors to generate reproducible radiographic views from two perpendicular angles. Specimens were kept at 5 °C and wrapped in polythene bags to reduce the impact of putrefaction.
RESULTS
Standardised head radiography technique was developed for superior-inferior and lateral views demonstrating porcine anatomy. Key parameters included: automatic exposure control for tube current (∼4 mAs), tube voltage of 73 kVp, 100 cm source to image receptor distance, and an anti-scatter grid. Slight variances in specimen morphology, developmental status, and soft tissue changes did not affect imaging outcomes.
CONCLUSION
The technique and positioning proposed in this study allows for the acquisition of high quality and reproducible radiographic images for comparable ballistic research datasets. Specimen positioning and centring of the primary beam may be applied across porcine breeds, although individual radiographic parameters may differ according to equipment specifications and specimen size.
IMPLICATIONS FOR PRACTICE
Development of a reproducible radiographic technique of porcine heads in forensic and veterinary research.
Topics: Adult; Humans; Swine; Animals; Female; Radiographic Image Enhancement; Phantoms, Imaging; Radiography
PubMed: 37595528
DOI: 10.1016/j.radi.2023.08.001 -
Cells Aug 2021The sperm flagellum is essential for the transport of the genetic material toward the oocyte and thus the transmission of the genetic information to the next generation.... (Review)
Review
The sperm flagellum is essential for the transport of the genetic material toward the oocyte and thus the transmission of the genetic information to the next generation. During the haploid phase of spermatogenesis, i.e., spermiogenesis, a morphological and molecular restructuring of the male germ cell, the round spermatid, takes place that includes the silencing and compaction of the nucleus, the formation of the acrosomal vesicle from the Golgi apparatus, the formation of the sperm tail, and, finally, the shedding of excessive cytoplasm. Sperm tail formation starts in the round spermatid stage when the pair of centrioles moves toward the posterior pole of the nucleus. The sperm tail, eventually, becomes located opposed to the acrosomal vesicle, which develops at the anterior pole of the nucleus. The centriole pair tightly attaches to the nucleus, forming a nuclear membrane indentation. An articular structure is formed around the centriole pair known as the connecting piece, situated in the neck region and linking the sperm head to the tail, also named the head-to-tail coupling apparatus or, in short, HTCA. Finally, the sperm tail grows out from the distal centriole that is now transformed into the basal body of the flagellum. However, a centriole pair is found in nearly all cells of the body. In somatic cells, it accumulates a large mass of proteins, the pericentriolar material (PCM), that together constitute the centrosome, which is the main microtubule-organizing center of the cell, essential not only for the structuring of the cytoskeleton and the overall cellular organization but also for mitotic spindle formation and chromosome segregation. However, in post-mitotic (G1 or G0) cells, the centrosome is transformed into the basal body. In this case, one of the centrioles, which is always the oldest or mother centriole, grows the axoneme of a cilium. Most cells of the body carry a single cilium known as the primary cilium that serves as an antenna sensing the cell's environment. Besides, specialized cells develop multiple motile cilia differing in substructure from the immotile primary cilia that are essential in moving fluids or cargos over the cellular surface. Impairment of cilia formation causes numerous severe syndromes that are collectively subsumed as ciliopathies. This comparative overview serves to illustrate the molecular mechanisms of basal body formation, their similarities, and dissimilarities, in somatic versus male germ cells, by discussing the involved proteins/genes and their expression, localization, and function. The review, thus, aimed to provide a deeper knowledge of the molecular players that is essential for the expansion of clinical diagnostics and treatment of male fertility disorders.
Topics: Basal Bodies; Centrosome; Germ Cells; Humans; Infertility, Male; Male; Spermatogenesis
PubMed: 34571916
DOI: 10.3390/cells10092266