Experimental evidence in the in vivo canine for the collapsible tube model of phonation

1991 ◽  
Vol 89 (3) ◽  
pp. 1358-1363 ◽  
Author(s):  
Gerald S. Berke ◽  
David C. Green ◽  
Marshall E. Smith ◽  
David P. Arnstein ◽  
Vincent Honrubia ◽  
...  
Keyword(s):  
Experimental Evidence ◽  
Tube Model ◽  
Collapsible Tube

Effect of Tension, Stiffness, and Airflow on Laryngeal Resistance in the in Vivo Canine Model

1993 ◽  
Vol 102 (10) ◽  
pp. 761-768 ◽  
Author(s):  
Steven Bielamowicz ◽  
Joel A. Sercarz ◽  
Gerald S. Berke ◽  
David C. Green ◽  
Jody Kreiman ◽  
...  
Keyword(s):  
Recurrent Laryngeal Nerve ◽  
Superior Laryngeal Nerve ◽  
Canine Model ◽  
Laryngeal Nerve ◽  
Tube Model ◽  
Collapsible Tube ◽  
Data Support ◽  
The Relationship ◽  
Laryngeal Resistance

This study used an in vivo canine model of phonation to determine the effects of airflow on glottal resistance at low, medium, and high levels of recurrent laryngeal nerve (RLN) and superior laryngeal nerve (SLN) stimulation. Static and dynamic trials of changing airflow were used to study the effects of airflow on glottal resistance during phonation. As reported previously, glottal resistance varies inversely as a function of airflow. Increasing levels of RLN stimulation resulted in a statistically significant increase in glottal resistance for each level of airflow evaluated. Variation in SLN stimulation had no statistically significant effects on the relationship between flow and resistance. At airflow rates greater than 590 milliliters per second (mL/s), glottal resistance approached 0.1 mm Hg per mL/s for all levels of RLN and SLN stimulation tested. These data support the collapsible tube model of phonation.

scholarly journals Experimental Evidence for Therapeutic Potentials of Propolis

Nutrients ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 2528
Author(s):  
Priyanshu Bhargava ◽  
Debajit Mahanta ◽  
Ashish Kaul ◽  
Yoshiyuki Ishida ◽  
Keiji Terao ◽  
...  
Keyword(s):  
New Zealand ◽  
Experimental Evidence ◽  
Antioxidant Properties ◽  
Geographic Location ◽  
Caffeic Acid Phenethyl Ester ◽  
Candidate Drug ◽  
Brazilian Propolis ◽  
Brazilian Green Propolis

Propolis is produced by honeybees from materials collected from plants they visit. It is a resinous material having mixtures of wax and bee enzymes. Propolis is also known as bee glue and used by bees as a building material in their hives, for blocking holes and cracks, repairing the combs and strengthening their thin borders. It has been extensively used since ancient times for different purposes in traditional human healthcare practices. The quality and composition of propolis depend on its geographic location, climatic zone and local flora. The New Zealand and Brazilian green propolis are the two main kinds that have been extensively studied in recent years. Their bioactive components have been found to possess a variety of therapeutic potentials. It was found that Brazilian green propolis improves the cognitive functions of mild cognitive impairments in patients living at high altitude and protects them from neurodegenerative damage through its antioxidant properties. It possesses artepillin C (ARC) as the key component, also known to possess anticancer potential. The New Zealand propolis contains caffeic acid phenethyl ester (CAPE) as the main bioactive with multiple therapeutic potentials. Our lab performed in vitro and in vivo assays on the extracts prepared from New Zealand and Brazilian propolis and their active ingredients. We provided experimental evidence that these extracts possess anticancer, antistress and hypoxia-modulating activities. Furthermore, their conjugation with γCD proved to be more effective. In the present review, we portray the experimental evidence showing that propolis has the potential to be a candidate drug for different ailments and improve the quality of life.

scholarly journals Hypertrophic cardiomyopathy MYH7 mutation R723G alters mRNA secondary structure

2020 ◽  
Vol 52 (1) ◽  
pp. 15-19
Author(s):  
J. Rose ◽  
T. Kraft ◽  
B. Brenner ◽  
J. Montag
Keyword(s):  
Hypertrophic Cardiomyopathy ◽  
Secondary Structure ◽  
Experimental Evidence ◽  
Point Mutation ◽  
Shape Analysis ◽  
Allelic Imbalance ◽  
Mrna Secondary Structure ◽  
Wild Type ◽  
Mrna Structure

Point mutation R723G in the MYH7 gene causes hypertrophic cardiomyopathy (HCM). Heterozygous patients with this mutation exhibit a comparable allelic imbalance of the MYH7 gene. On average 67% of the total MYH7 mRNA are derived from the MYH7R723G-allele and 33% from the MYH7WT allele. Mechanisms underlying mRNA allelic imbalance are largely unknown. We suggest that a different mRNA lifetime of the alleles may cause the allelic drift in R723G patients. A potent regulator of mRNA lifetime is its secondary structure. To test for alterations in the MYH7R723G mRNA structure we used selective 2′-hydroxyl acylation analyzed by primer extension (SHAPE) analysis. We show significantly different SHAPE reactivity of wild-type and MYH7R723G RNA, which is in accordance with bioinformatically predicted structures. Thus, we provide the first experimental evidence for mRNA secondary structure alterations by the HCM point mutation. We assume that this may result in a prolonged lifetime of MYH7R723G mRNA in vivo and subsequently in the determined allelic imbalance.

Blue LED treatment of superficial abrasions: in vivo experimental evidence of wound healing improvement

2018 ◽  
Author(s):  
Giada Magni ◽  
Francesca Rossi ◽  
Francesca Tatini ◽  
Riccardo Cicchi ◽  
Lucia Cavigli ◽  
...  
Keyword(s):  
Wound Healing ◽  
Experimental Evidence ◽  
Blue Led

Functional consequences of contrasting properties of α1/α2 systems

1985 ◽  
Vol 68 (s10) ◽  
pp. 93s-97s ◽  
Author(s):  
Pieter B. M. W. M. Timmermans ◽  
Martin J. M. C. Thoolen ◽  
Adriaan De Jonge ◽  
Bob Wilffert ◽  
Pieter A. Van Zwieten
Keyword(s):  
Smooth Muscle ◽  
Experimental Evidence ◽  
Diastolic Pressure ◽  
Previous Treatment ◽  
Pithed Rat ◽  
Pithed Rats ◽  
Functional Consequences ◽  
Adrenoceptor Agonists

Ample experimental evidence supports the existence of two distinct types of vasoconstrictor α-adrenoceptors in vascular smooth muscle at postjunctional sites, showing similarities with α1 and α2-adrenoceptors. Especially in vivo, the characterization of an α2-adrenoceptor mediating an increase in diastolic pressure has been most successful. In this respect the model of the pithed rat has been employed most frequently (for reviews see [1, 2]). At present, the agents cirazoline, (−) phenylephrine, (±)-erythro-methoxamine, (−)-amidephrine, SKF89748, St587 and Sgd 101/75 fulfil the criteria for selective α1-adrenoceptor agonists; their log dose-vasopressor effect curves are virtually unaffected by previous treatment with yohimbine or rauwolscine (selective dose in pithed rats: 1 mg/kg), whereas prazosin (selective dose in pithed rats: 0.1 mg/kg) causes an appreciable parallel rightward displacement. The reverse holds true for the stimulants B-HT 920, B-HT 933, B-HT 958, UK-14304, xylazine, TL-99, M-7 and DP-6,7-ADTN, which all have been classified as preferential agonists of vascular postjunctional α-adrenoceptors.

scholarly journals A Red Wine Vinegar Beverage can Inhibit the Renin-Angiotensin System: Experimental Evidence in Vivo

2005 ◽  
Vol 28 (7) ◽  
pp. 1208-1210 ◽  
Author(s):  
Sachiko Honsho ◽  
Atsushi Sugiyama ◽  
Akira Takahara ◽  
Yoshioki Satoh ◽  
Yuji Nakamura ◽  
...  
Keyword(s):  
Experimental Evidence ◽  
Red Wine ◽  
Renin Angiotensin System ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Wine Vinegar

scholarly journals Recapitulating Cross-Species Transmission of Simian Immunodeficiency Virus SIVcpz to Humans by Using Humanized BLT Mice

2016 ◽  
Vol 90 (17) ◽  
pp. 7728-7739 ◽  
Author(s):  
Zhe Yuan ◽  
Guobin Kang ◽  
Fangrui Ma ◽  
Wuxun Lu ◽  
Wenjin Fan ◽  
...  
Keyword(s):  
Experimental Evidence ◽  
Transmission Risk ◽  
Crossing Over ◽  
Phylogenetic Distance ◽  
Immunodeficiency Virus ◽  
Blt Mice ◽  
Hiv 1

ABSTRACTThe origins of human immunodeficiency virus type 1 (HIV-1) have been widely accepted to be the consequences of simian immunodeficiency viruses from wild chimpanzees (SIVcpz) crossing over to humans. However, there has not been anyin vivostudy of SIVcpz infection of humans. Also, it remains largely unknown why only specific SIVcpz strains have achieved cross-species transmission and what transmission risk might exist for those SIVcpz strains that have not been found to infect humans. Closing this knowledge gap is essential for better understanding cross-species transmission and predicting the likelihood of additional cross-species transmissions of SIV into humans. Here we show that humanized bone marrow, thymus, and liver (hu-BLT) mice are susceptible to all studied strains of SIVcpz, including the inferred ancestral viruses of pandemic and nonpandemic HIV-1 groups M (SIVcpzMB897) and N (SIVcpzEK505) as well as strains that have not been found in humans (SIVcpzMT145 and SIVcpzBF1167). Importantly, the ability of SIVcpz to cross the interspecies barrier to infect humanized mice correlates with their phylogenetic distance to pandemic HIV-1. We also identified mutations of SIVcpzMB897 (Env G411R and G413R) and SIVcpzBF1167 (Env H280Q and Q380R) at 14 weeks postinoculation. Together, our results have recapitulated the events of SIVcpz cross-species transmission to humans and identified mutations that occurred during the first 16 weeks of infection, providingin vivoexperimental evidence that the origins of HIV-1 are the consequence of SIVcpz crossing over to humans. This study also revealed that SIVcpz viruses whose inferred descendants have not been found in humans still have the potential to cause an HIV-1-like zoonosis.IMPORTANCEIt is believed that the origins of HIV-1 are the consequence of SIV from wild chimpanzees crossing over to humans. However, the origins of HIV-1 have been linked back to only specific SIVcpz strains. There have been no experiments that directly test thein vivocross-species transmissibility of SIVcpz strains to humans. This is the firstin vivostudy of SIVcpz cross-species transmission. With the humanized-BLT mouse model, we have providedin vivoexperimental evidence of multiple SIVcpz strains crossing over to humans and identified several important mutations of divergent SIVcpz strains after long-term replication in human cells. We also found that the cross-species transmission barrier of SIVcpz to humans correlates with their phylogenetic distance to pandemic HIV-1 group M. Importantly, this work provides evidence that SIVcpz viruses, whose inferred descendants have not been found in humans, still have the potential to cause a future HIV-1-like zoonotic outbreak.

scholarly journals On the existence of a central respiratory oxygen sensor

2017 ◽  
Vol 123 (5) ◽  
pp. 1344-1349 ◽  
Author(s):  
Alexander V. Gourine ◽  
Gregory D. Funk
Keyword(s):  
Experimental Evidence ◽  
Oxygen Sensor ◽  
Ventilatory Response ◽  
Lung Ventilation ◽  
Partial Recovery ◽  
Hypoxic Ventilatory Response ◽  
Peripheral Chemoreceptor ◽  
Terrestrial Mammals

A commonly held view that dominates both the scientific and educational literature is that in terrestrial mammals the central nervous system lacks a physiological hypoxia sensor capable of triggering increases in lung ventilation in response to decreases in Po2 of the brain parenchyma. Indeed, a normocapnic hypoxic ventilatory response has never been observed in humans following bilateral resection of the carotid bodies. In contrast, almost complete or partial recovery of the hypoxic ventilatory response after denervation/removal of the peripheral respiratory oxygen chemoreceptors has been demonstrated in many experimental animals when assessed in an awake state. In this essay we review the experimental evidence obtained using in vitro and in vivo animal models, results of human studies, and discuss potential mechanisms underlying the effects of CNS hypoxia on breathing. We consider experimental limitations and discuss potential reasons why the recovery of the hypoxic ventilatory response has not been observed in humans. We review recent experimental evidence suggesting that the lower brain stem contains functional oxygen sensitive elements capable of stimulating respiratory activity independently of peripheral chemoreceptor input.

A coupled hydrodynamic model of the cardiovascular and cerebrospinal fluid system

2012 ◽  
Vol 302 (7) ◽  
pp. H1492-H1509 ◽  
Author(s):  
Bryn A. Martin ◽  
Philippe Reymond ◽  
Jan Novy ◽  
Olivier Balédent ◽  
Nikolaos Stergiopulos
Keyword(s):  
Blood Flow ◽  
Cerebrospinal Fluid ◽  
Cerebral Blood Flow ◽  
Transfer Function ◽  
Tube Model ◽  
Tree Model ◽  
Pulse Delay ◽  
Arterial Network ◽  
In Vivo Measurements

Coupling of the cardiovascular and cerebrospinal fluid (CSF) system is considered to be important to understand the pathophysiology of cerebrovascular and craniospinal disease and intrathecal drug delivery. A coupled cardiovascular and CSF system model was designed to examine the relation of spinal cord (SC) blood flow (SCBF) and CSF pulsations along the spinal subarachnoid space (SSS). A one-dimensional (1-D) cardiovascular tree model was constructed including a simplified SC arterial network. Connection between the cardiovascular and CSF system was accomplished by a transfer function based on in vivo measurements of CSF and cerebral blood flow. A 1-D tube model of the SSS was constructed based on in vivo measurements in the literature. Pressure and flow throughout the cardiovascular and CSF system were determined for different values of craniospinal compliance. SCBF results indicated that the cervical, thoracic, and lumbar SC each had a signature waveform shape. The cerebral blood flow to CSF transfer function reproduced an in vivo-like CSF flow waveform. The 1-D tube model of the SSS resulted in a distribution of CSF pressure and flow and a wave speed that were similar to those in vivo. The SCBF to CSF pulse delay was found to vary a great degree along the spine depending on craniospinal compliance and vascular anatomy. The properties and anatomy of the SC arterial network and SSS were found to have an important impact on pressure and flow and perivascular fluid movement to the SC. Overall, the coupled model provides predictions about the flow and pressure environment in the SC and SSS. More detailed measurements are needed to fully validate the model.

Sign in / Sign up

Export Citation Format

Share Document