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Iranian Journal of Basic Medical... Feb 2023Studying the effect of melatonin pretreatment and ischemic preconditioning on renal ischemia-reperfusion injury (IRI).
OBJECTIVES
Studying the effect of melatonin pretreatment and ischemic preconditioning on renal ischemia-reperfusion injury (IRI).
MATERIALS AND METHODS
Forty-eight Wistar rats were randomized into six groups: control, sham operation, IRI (IRI in left kidney + right nephrectomy), IRI+ischemic preconditioning, IRI+Melatonin, and IRI+ischemic preconditioning+Melatonin groups. Melatonin (10 mg/kg) was intraperitoneally injected for 4 weeks before renal IRI. Ischemic preconditioning was performed by three cycles of 2 min-ischemia followed by 5 min-reperfusion period. A right nephrectomy was initially done and the left renal artery was clamped for 45 min. After 24 hr of ischemia-reperfusion, rats were decapitated. Kidney tissue samples were taken for histopathological assessment and the determination of kidney proinflammatory and anti-inflammatory cytokines, apoptotic protein caspase-3, oxidative stress markers, and activities of antioxidant enzymes. Serum creatinine and blood urea nitrogen (BUN) concentrations were measured for evaluation of renal function.
RESULTS
Renal IRI animals showed increased levels of creatinine, BUN, tumor necrosis factor-α (TNF-α), caspase-3, total nitrite/nitrate, and malondialdehyde (MDA), and decreased levels of interleukin-13 (IL-13), and activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD). Melatonin pretreatment or ischemic preconditioning resulted in decreased creatinine, BUN, TNF-α, caspase-3, nitrite/nitrate, and MDA, and increased IL-13, GPx, and SOD, with improved histopathological changes. Combined melatonin and ischemic preconditioning showed more effective improvement in renal IRI changes rather than melatonin or ischemic preconditioning alone.
CONCLUSION
Combined melatonin and ischemic preconditioning have better beneficial effects on renal IRI than applying each one alone.
PubMed: 36742133
DOI: 10.22038/IJBMS.2022.67127.14722 -
Romanian Journal of Morphology and... 2019Born on April 15, 1452, in a modest family in a hamlet from Tuscany, Leonardo da Vinci became the unassailable icon of Renaissance. Pushed throughout his entire life by... (Review)
Review
Born on April 15, 1452, in a modest family in a hamlet from Tuscany, Leonardo da Vinci became the unassailable icon of Renaissance. Pushed throughout his entire life by his relentless curiosity, he was a painter, draughtsman, sculptor, poet, musician, writer, engineer, stage designer, architect, physicist, astronomer, cartographer and anatomist. His earliest surviving anatomical drawings (ca. 1485-1493) include studies of the skull, meninges, brain and cerebral ventricles. He was the first to pith a frog, concluding that piercing the spinal medulla will result in immediate death - a completely unexpected result in that era. In an effort to better understand the origins of the sensory and motor functions of the brain - which at the time was believed to be in the ventricles - he developed a method of injecting hot wax into the ventricles of an ox. He was the first to correctly describe the four ventricles of the brain. Thus, he circumvented a 16 century-long flaw in the dissection technique, which did not allow the correct study of the shape of the ventricles - decapitation and drainage of fluids before study. Even though he was never formally educated in the study of medicine, his work continues to inspire us today, 500 years after his death.
Topics: Anatomists; Animals; History, 15th Century; History, 16th Century; Humans
PubMed: 32239124
DOI: No ID Found -
PloS One 2019Little is known about the precise date of the emergence of decapitation in a ritual context and the presence of systematic postmortem modification patterns in the...
Little is known about the precise date of the emergence of decapitation in a ritual context and the presence of systematic postmortem modification patterns in the ancient Central Andes. The ceremonial complex at Pacopampa in the northern Peruvian highlands provides early osteological evidence of decapitation in six individuals dating to the latter half of the Late-Final Formative Periods (500-50 BC) and to the Early Cajamarca Period (AD 200-450). Based on osteological evidence, and when taken together with archaeological settings and settlement patterns, researchers can be certain that those whose heads were disembodied were not likely to have been involved in organized battles. In addition, the similarities in the cut-mark distribution, direction, and cross-sectional morphology of each individual's remains, as well as the characteristics of selected individuals, imply that the decapitated individuals were carefully prepared using a standardized method and that those who modified the heads may have been professional decapitators. This study offers indisputable bioarchaeological evidence of ritualistic offerings of human skulls and systematic postmortem modification patterns, which is consistent with a contemporaneous iconographic motif of decapitation and extends the chronology of this practice back to the Formative Period in the northern Peruvian highlands.
Topics: Adolescent; Adult; Archaeology; Decapitation; Ecosystem; Female; Fractures, Bone; Geography; Humans; Male; Mandible; Middle Aged; Peru; Postmortem Changes; Young Adult
PubMed: 30620764
DOI: 10.1371/journal.pone.0210458 -
Journal of Interventional Medicine Feb 2023This study investigated the anatomical and histological characteristics of the rat Eustachian tube (E-tube) and the feasibility of Eustachian tubography in a rat model.
PURPOSE
This study investigated the anatomical and histological characteristics of the rat Eustachian tube (E-tube) and the feasibility of Eustachian tubography in a rat model.
MATERIALS AND METHODS
Fifteen male Wistar rats were used in this study, and the bilateral E-tubes of each rat were examined. Ten E-tubes were used for anatomical studies, another ten for histological analysis, and the other ten for Eustachian tubography. Five rats were euthanized and decapitated, and ten E-tubes were dissected to describe the anatomy of the E-tube. Ten E-tube specimens obtained from five other rats were sectioned to investigate E-tube histology. Eustachian tubography was performed on the bilateral E-tubes of the other five rats using the -tympanic approach.
RESULTS
The rat E-tubes consisted of bony and membranous parts. Cartilage and bone tissue covered only the bony part. The E-tubes' mean diameter and overall length were 2.97 mm and 4.96 mm, respectively. The tympanic orifices' mean diameter was 1.21 mm. The epithelium of E-tubes was mainly composed of pseudostratified ciliated and goblet cells. Eustachian tubography was successfully performed on both sides of the E-tube for each rat. The technical success rate was 100%, the average running time was 4.9 min, and no procedure-related complications occurred. On tubography images, the E-tube, tympanic cavity, and nasopharynx could be identified because of the visualization of bony landmarks.
CONCLUSION
In this study, we described the anatomical and histological features of rat E-tubes. With the aid of these findings, E-tube angiography was successfully performed using a transtympanic approach. These results will facilitate further investigation of E-tube dysfunction.
PubMed: 37180372
DOI: 10.1016/j.jimed.2022.12.002 -
The Journal of Pharmacology and... Jun 20213,4-Methylenedioxy--methylcathinone (methylone) is a new psychoactive substance with stimulant properties and potential for abuse. Despite its popularity, limited...
3,4-Methylenedioxy--methylcathinone (methylone) is a new psychoactive substance with stimulant properties and potential for abuse. Despite its popularity, limited studies have examined relationships between brain concentrations of methylone, its metabolites, and pharmacodynamic effects. The goal of the present study was 2-fold: 1) to determine pharmacokinetics of methylone and its major metabolites-4-hydroxy-3-methoxy-methylcathinone (HMMC), 3,4-dihydroxy-methylcathinone (HHMC), and 3,4-methylenedioxycathinone (MDC)-in rat brain and plasma and 2) to relate brain pharmacokinetic parameters to pharmacodynamic effects including locomotor behavior and postmortem neurochemistry. Male Sprague-Dawley rats received subcutaneous methylone (6, 12, or 24 mg/kg) or saline vehicle ( = 16/dose), and subgroups were decapitated after 40 or 120 minutes. Plasma and prefrontal cortex were analyzed for concentrations of methylone and its metabolites by liquid chromatography-tandem mass spectrometry. Frontal cortex and dorsal striatum were analyzed for dopamine, 5-HT, and their metabolites by high-performance liquid chromatography-electrochemical detection. Brain and plasma concentrations of methylone and its metabolites rose with increasing methylone dose, but brain methylone and MDC concentrations were greater than dose-proportional. Brain-to-plasma ratios for methylone and MDC were ≥ 3 (range 3-12), whereas those for HHMC and HMMC were ≤ 0.2 (range 0.01-0.2). Locomotor activity score was positively correlated with brain methylone and MDC, whereas cortical 5-HT was negatively correlated with these analytes at 120 minutes. Our findings show that brain concentrations of methylone and MDC display nonlinear accumulation. Behavioral and neurochemical effects of systemically administered methylone are related to brain concentrations of methylone and MDC but not its hydroxylated metabolites, which do not effectively penetrate into the brain. SIGNIFICANCE STATEMENT: Behavioral and neurochemical effects of methylone are related to brain concentrations of methylone and its metabolite MDC but not its hydroxylated metabolites, 4-hydroxy-3-methoxy-methylcathinone and 3,4-dihydroxy-methylcathinone, which do not effectively penetrate into the brain. Methylone and MDC display nonlinear accumulation in the brain, which could cause untoward effects on serotonin neurons in vulnerable brain regions, including the frontal cortex.
Topics: Animals; Brain; Dopamine; Rats; Serotonin
PubMed: 33785525
DOI: 10.1124/jpet.121.000531 -
Journal of Spine Surgery (Hong Kong) Dec 2015Increasing focus has been placed on the use of simulation in neurosurgical and spinal surgical training worldwide, with the establishment of many surgical laboratories...
BACKGROUND
Increasing focus has been placed on the use of simulation in neurosurgical and spinal surgical training worldwide, with the establishment of many surgical laboratories dedicated to such purpose. So far, the opportunities for hands-on cadaveric training in the areas of neurosurgery and spine surgery remain limited in Australia, owing to various factors, including the abolition of dissection in many medical schools, high maintenance requirements and widespread geographical distribution of surgical trainees.
METHODS
We established a cadaver-based neurosurgical laboratory based at the medical school of the University of New England in Armidale, Australia, which is used by the surgical dissection course for junior surgical trainees offered by the university. We reported our experiences in setting up a neurosurgical research laboratory, and explored the feasibility of establishing a cost-effective anatomical research facility in a rural setting in Australia.
RESULTS
We found that Genelyn(TM)-fixed cadavers had limited movements of the head as required for adequate surgical positioning and exposure. Furthermore, we discovered that bodies embalmed via the femoral vein had poorly perfused heads after surgical exposure, and thus decapitation had to be performed unfortunately for our purpose. Cadaver samples and surgical equipment were sourced from various veterinary practices and commercial companies. Using human and animal cadavers, this laboratory provided trainees with hands-on opportunities to improve their surgical skills and neuroanatomical knowledge, as well as develop familiarity with highly specialized surgical equipment.
CONCLUSIONS
We demonstrated the feasibility of establishing a cost-effective neurosurgical research laboratory in Australia and discussed various aspects of its maintenance.
PubMed: 27683680
DOI: 10.3978/j.issn.2414-469X.2015.09.02 -
PloS One 2021The rotenone-induced animal model of Parkinson's disease (PD) has been used to investigate the pathogenesis of PD. Oxidative stress is one of the main contributors of...
The rotenone-induced animal model of Parkinson's disease (PD) has been used to investigate the pathogenesis of PD. Oxidative stress is one of the main contributors of neurodegeneration in PD. Flavonoids have the potential to modulate neuronal function and combat various neurodegenerative diseases. The pre- and post-supplementation of quercetin (50 mg/kg, p.o) was done in rats injected with rotenone (1.5 mg/kg, s.c). After the treatment, behavioral activities were monitored for motor activity, depression-like behavior, and cognitive changes. Rats were decapitated after behavioral analysis and the brain samples were dissected out for neurochemical and biochemical estimation. Results showed that supplementation of quercetin significantly (p<0.01) restored rotenone-induced motor and non-motor deficits (depression and cognitive impairments), enhanced antioxidant enzyme activities (p<0.01), and attenuated neurotransmitter alterations (p<0.01). It is suggested that quercetin supplementation improves neurotransmitter levels by mitigating oxidative stress via increasing antioxidant enzyme activity and hence improves motor activity, cognitive functions, and reduces depressive behavior. The results of the present study showed that quercetin pre-supplementation produced more significant results as compared to post-supplementation. These findings show that quercetin can be a potential therapeutic agent to reduce the risk and progression of PD.
Topics: Animals; Antioxidants; Behavior, Animal; Cognition; Cognitive Dysfunction; Depression; Disease Models, Animal; Male; Motor Activity; Neuroprotective Agents; Neurotransmitter Agents; Oxidative Stress; Parkinson Disease, Secondary; Quercetin; Rats; Rats, Wistar; Rotenone; Signal Transduction; Treatment Outcome
PubMed: 34767546
DOI: 10.1371/journal.pone.0258928 -
PloS One 2021We aimed to describe the epidemiology of statue attacks along with statue representativeness relative to modern day demographics in one case study country: New Zealand.
OBJECTIVES
We aimed to describe the epidemiology of statue attacks along with statue representativeness relative to modern day demographics in one case study country: New Zealand.
METHODS
We performed Internet searches for the existence of outdoor statues of named individuals and historical attacks in New Zealand (NZ), combined a national survey with field visits to all identified statues to examine for injuries and repairs.
RESULTS
Of the 123 statues identified, nearly a quarter (n = 28, 23%) had been attacked at least once (total of 45 separate attack events), with the number of attacks increasing from the 1990s. Attacks involved paint/graffiti (14% of all statues at least once), nose removal/damage (7%), decapitation (5%), and total destruction (2%). The risk of attack was relatively higher for statues of royalty (50%), military personnel (33%), explorers (29%), and politicians (25%), compared to other reasons for fame (eg, 0% for sports players). Statue subjects involved in colonialism or direct harm to Māori (Indigenous population), had 6.61 (95%CI: 2.30 to 19.9) greater odds (adjusted odds ratio) of being attacked than other subjects. Most of the statue subjects were of men (87%) and Europeans (93%). Other ethnicities were 6% Māori (comprising 15% of the population) and 1% each for Asian and Pacific peoples, who comprise 12% and 7% of the population respectively.
CONCLUSIONS
This national survey found an association between statue attacks and the role of statue subjects in colonialism or direct harm to the Indigenous population. Furthermore, the demography of the statue subjects may represent historical and current social power relationships-with under-representation of women and non-European ethnic groups.
Topics: Crime; Humans; New Zealand
PubMed: 34081698
DOI: 10.1371/journal.pone.0252567 -
BMC Neuroscience Feb 2022The TRH/TRH-R1 receptor signaling pathway within the neurons of the dorsal vagal complex is an important mediator of the brain-gut axis. Mental health and protection...
BACKGROUND
The TRH/TRH-R1 receptor signaling pathway within the neurons of the dorsal vagal complex is an important mediator of the brain-gut axis. Mental health and protection from a variety of neuropathologies, such as autism, Attention Deficit Hyperactivity Disorder, Alzheimer's and Parkinson's disease, major depression, migraine and epilepsy are influenced by the gut microbiome and is mediated by the vagus nerve. The antibiotic rifaximin (RF) does not cross the gut-blood barrier. It changes the composition of the gut microbiome resulting in therapeutic benefits for traveler's diarrhea, hepatic encephalopathy, and prostatitis. TRH and TRH-like peptides, with the structure pGlu-X-Pro-NH, where "X" can be any amino acid residue, have reproduction-enhancing, caloric-restriction-like, anti-aging, pancreatic-β cell-, cardiovascular-, and neuroprotective effects. TRH and TRH-like peptides occur not only throughout the CNS but also in peripheral tissues. To elucidate the involvement of TRH-like peptides in brain-gut-reproductive system interactions 16 male Sprague-Dawley rats, 203 ± 6 g, were divided into 4 groups (n = 4/group): the control (CON) group remained on ad libitum Purina rodent chow and water for 10 days until decapitation, acute (AC) group receiving 150 mg RF/kg powdered rodent chow for 24 h providing 150 mg RF/kg body weight for 200 g rats, chronic (CHR) animals receiving RF for 10 days; withdrawal (WD) rats receiving RF for 8 days and then normal chow for 2 days.
RESULTS
Significant changes in the levels of TRH and TRH-like peptides occurred throughout the brain and peripheral tissues in response to RF. The number of significant changes in TRH and TRH-like peptide levels in brain resulting from RF treatment, in descending order were: medulla (16), piriform cortex (8), nucleus accumbens (7), frontal cortex (5), striatum (3), amygdala (3), entorhinal cortex (3), anterior (2), and posterior cingulate (2), hippocampus (1), hypothalamus (0) and cerebellum (0). The corresponding ranking for peripheral tissues were: prostate (6), adrenals (4), pancreas (3), liver (2), testis (1), heart (0).
CONCLUSIONS
The sensitivity of TRH and TRH-like peptide expression to RF treatment, particularly in the medulla oblongata and prostate, is consistent with the participation of these peptides in the therapeutic effects of RF.
Topics: Animals; Brain; Diarrhea; Female; Male; Peptides; Rats; Rats, Sprague-Dawley; Rifaximin; Thyrotropin-Releasing Hormone; Travel
PubMed: 35189807
DOI: 10.1186/s12868-022-00694-z -
Anaesthesia Sep 2020Historically, there has been a tendency to think that there are two types of death: circulatory and neurological. Holding onto this tendency is making it harder to... (Review)
Review
Historically, there has been a tendency to think that there are two types of death: circulatory and neurological. Holding onto this tendency is making it harder to navigate emerging resuscitative technologies, such as extracorporeal membrane oxygenation and the recent well-publicised experiment that demonstrated the possibility of restoring cellular function to some brain neurons 4 h after normothermic circulatory arrest (decapitation) in pigs. Attempts have been made to respond to these difficulties by proposing a unified brain-based criterion for human death, which we call 'permanent brain arrest'. The clinical characteristics of permanent brain arrest are the permanent loss of capacity for consciousness and permanent loss of all brainstem functions, including the capacity to breathe. These losses could arise from a primary brain injury or as a result of systemic circulatory arrest. We argue that permanent brain arrest is the true and sole criterion for the death of human beings and show that this is already implicit in the circulatory-respiratory criterion itself. We argue that accepting the concept of permanent cessation of brain function in patients with systemic permanent circulatory arrest will help us better navigate the medical advances and new technologies of the future whilst continuing to provide sound medical criteria for the determination of death.
Topics: Brain Death; Heart Arrest; Humans
PubMed: 32430978
DOI: 10.1111/anae.15050