scholarly journals The discovery of lymphatic system as a turning point in medical knowledge: Aselli, Pecquet and the end of hepatocentrism

2017 ◽  
Vol 2 (2) ◽  
pp. 67-76
Author(s):  
Luca Tonetti
Keyword(s):  
Portal Vein ◽  
Human Body ◽  
Thoracic Duct ◽  
Blood Circulation ◽  
Turning Point ◽  
Lymphatic System ◽  
Venous Blood ◽  
Medical Knowledge ◽  
17Th Century ◽  
The Impact

In this paper, I would like to analyse the impact of the discovery of lymphatic system on the development of the modern conception of human body. The discovery of lymphatics, as that of blood circulation, has in fact questioned important tenets of Galen's anatomo-physiology. Galen defended a 'dualistic conception' of the blood: he distinguished two different systems, the hepatic-venous system and the cardio-arterial one. The liver played a pivotal role because it was believed to transform the chyle received by the portal vein into venous blood. The discovery of lymphatics challenged this view: 17th-century anatomical dissections and experiments, starting with the discovery of milky veins by Gaspare Aselli (1581-1625) and the studies on thoracic duct by Jean Pecquet (1622-1674), irrefutably showed that the chyle does not pour out in the liver and that, consequently, the liver does not produce blood.

Portal venous transport of long-chain fatty acids absorbed from rat intestine

1980 ◽  
Vol 239 (3) ◽  
pp. G141-G150 ◽  
Author(s):  
G. B. McDonald ◽  
D. R. Saunders ◽  
M. Weidman ◽  
L. Fisher
Keyword(s):  
Fatty Acids ◽  
Linoleic Acid ◽  
Portal Vein ◽  
Thoracic Duct ◽  
Infusion Rate ◽  
Venous Blood ◽  
Long Chain Fatty Acids ◽  
Rat Intestine ◽  
Portal Venous Blood ◽  
Long Chain

We studied the route of transport of long-chain fatty acids (LCFA) from the rat intestine. Lauric (12:0), myristic (14:0), palmitic (16:0), stearic (18:0), linoleic (18:2), and linolenic (18:3) acids were infused intraduodenally for 4 h as micellar solutions into unanesthetized thoracic duct-fistula rats. Proportionally more of each LCFA was transported by the portal vein at infusion rates of 0.3 mumol/h than at 15 mumol/h. Of the LCFA absorbed at low rates of infusion, 72% of lauric, 58% of myristic, 41% of palmitic, 28% of stearic, 58% of linoleic, and 68% of linolenic acid bypassed the lymphatic pathway. To test the inference that 58% of absorbed linoleate was transported by the portal vein, [14C]linoleic acid was infused at 0.3 or 15 mumol/h into unanesthetized rats equipped with both thoracic duct and portal venous fistulas. Portal venous blood (0.1 ml) was withdrawn every 30 min for 4 h. Proportionally more [14C]linoleate was recovered in portal blood at the low infusion rate. To examine the morphology of fat absorption, segments of rat jejunum in anesthetized rats were infused with micellar linoleic acid at 3 or 150 mumol/h. At 3-mumol/h infusion rate, an appearance identical to the fasting state was seen by electron microscopy. At 150 mumol/h, many larger chylomicron-sized particles appeared in absorptive cells, intercellular spaces, and lymphatics. We conclude that a substantial proportion of unsaturated LCFA is transported from rat intestine in portal venous blood.

scholarly journals The Variation Trend of the Human Body’s Susceptibility to SARS-CoV-2 over Time

2020 ◽  
Author(s):  
Bing Luo
Keyword(s):  
Human Body ◽  
Blood Circulation ◽  
Viral Infections ◽  
Venous Blood ◽  
Systemic Circulation ◽  
Venous Reflux ◽  
Blood Flows ◽  
Arterial Blood ◽  
The Earth ◽  
Over Time

In blood circulation (systemic circulation), the order of blood circulation is that arterial blood flows into capillaries only after venous blood refluxes. The human body controls the flow of arterial blood into capillaries by controlling the flow of venous blood. The refluxing power of venous blood changes with the rotation and revolution of the earth, and leads to changes in arterial blood obtained by cells, tissues and organs. If the refluxing power of venous blood of the lungs has a problem, the actual amount of blood obtained by the lungs will be less than the amount of blood distributed to the lungs by the human body (supplying the lungs with nutrients and oxygen they need), and what Pasteur called “the terrain” (There is a paragraph in Seasons of Life: “On his deathbed, Louis Pasteur, the founder of the germ theory of disease, allegedly said, ‘the germ is nothing, the terrain is everything’.”) will form in the lungs. The severity of problems induced by the intensity of venous reflux changes with time, leading to the variation of lung’s susceptibility to viral infections with time.

scholarly journals Simulation of Local Blood Flow in Human Brain Under Altered Gravity

2003 ◽  
Author(s):  
Chang Sung Kim ◽  
Cetin Kiris ◽  
Dochan Kwak
Keyword(s):  
Human Body ◽  
Space Flight ◽  
Blood Circulation ◽  
Space Shuttle ◽  
Flow Characteristics ◽  
Cardiovascular Research ◽  
Long Duration ◽  
Altered Blood ◽  
The Impact ◽  
The Brain

Blood circulation as well as body fluids distribution undergoes significant adaptation during and after space flight. Much study on physiological changes under weightlessness has been performed since the early days of the space program. In particular, cardiovascular research in conjunction with the space shuttle program has included diverse physiological functions affected by the nervous system such as heart rate, blood pressure, hormone release, and respiration. The altered cardiac output due to adaptation during flight and deconditioning after the flight will impact blood circulation in the human body. Especially, this altered blood supply in the brain and consequent oxygen supply to certain parts of the brain will make non-negligible impact on long-duration flight. To assess the impact of changing gravitational forces on human space flight, it will be essential to quantify the flow characteristics in the brain under varying gravity conditions. Analysis of blood circulation in brain as well as other parts of human body requires the capability to analyze flow in large arteries and capillaries.

scholarly journals La découverte de la circulation sanguine: révolution ou refonte?

Gesnerus ◽  
2011 ◽  
Vol 68 (1) ◽  
pp. 5-25
Author(s):  
Claire Crignon
Keyword(s):  
Human Nature ◽  
Scientific Revolution ◽  
Blood Circulation ◽  
Medical Knowledge ◽  
17Th Century ◽  
Anatomy And Physiology ◽  
Scientific Revolutions ◽  
Structure Of Scientific Revolutions ◽  
Circulation Sanguine ◽  
The Way

The discovery of the principle of blood circulation by William Harvey is generally considered as one of the major events of the “scientific revolution” of the 17th century. This paper reconsiders the question by taking in account the way Harvey’s discovery was discussed by some contemporary philosophers and physicians, in particular Fontenelle, who insisted on the necessity of redefining methods and principles of medical knowledge, basing themselves on the revival of anatomy and physiology, and of its consequences on the way it permits to think about the human nature. This return allows us to consider the opportunity of substituting the kuhnian scheme of “structure of scientific revolutions” for the bachelardian concept of “refonte”.

scholarly journals Impact of a cellphone electromagnetic radiation on phagocytic activity of neutrophils in vitro

2020 ◽  
Vol 99 (9) ◽  
pp. 925-929
Author(s):  
Maria S. Blyakher ◽  
Elena A. Tulskaya ◽  
Ivan V. Kapustin ◽  
Irina M. Fedorova ◽  
Vladimir G. Nesterenko ◽  
...  
Keyword(s):  
Electromagnetic Radiation ◽  
Human Body ◽  
Mobile Communications ◽  
Phagocytic Activity ◽  
Venous Blood ◽  
Enzyme Linked Immunosorbent Assay ◽  
Physiological Processes ◽  
Immunological Tests ◽  
The Impact

Introduction. The nature of a cellphone electromagnetic radiation (EMP) influence on the neutrophils in vitro activation was studied. The relevance of studying the impact of mobile communications and their effects on the body’s physiological processes is determined by the global prevalence of such tools and the research data inconsistency in the both domestic and foreign scientific literature. Material and methods. The object of the study was the whole venous blood samples and isolated neutrophils from 36 adult donors (aged from 22 to 65 years) of both genders. The responses of the neutrophils’ phagocytic activity and its registration were carried out in a flat-bottomed plate for enzyme-linked immunosorbent assay (ELISA), the daily culture of S. aureus ATCC 6538 (strain 209) was used as an inducer of phagocytosis. The intensity of phagocytosis was evaluated by changing the activity of myeloperoxidase (MPO) spectrophotometric method in our modification. Results. In the course of studies of the EMR impact of a cellphone on phagocytic neutrophils, the following was revealed: when culturing neutrophils without the addition of S. aureus, there was a tendency to increase spontaneous MPO activity (by 69%), i.e. its production in the absence of a stimulating factor and, conversely, a significant decrease in the enzyme activity induced by S. aureus (by 34%, p <0.05), i.e. the phagocytic activity of neutrophils. Conclusion We revealed the biological effect of the cellphone EMR as an increase in the spontaneous activity of MPO and a decrease in the bacterially induced activity of the enzyme may indicate a decline in the phagocytic activity of the main cells of the immune system, therefore, it demonstrates a weakening of the protective properties of the human body against infectious diseases. In previous studies, we have shown the presence of the impact of cellphone EMR on the activation of lymphocytes in vitro. The use of immunological tests can be a promising direction in assessing the impact of the cellphone EMR on the human body.

John Keats and Indian Medicine

Romanticism ◽  
2016 ◽  
Vol 22 (2) ◽  
pp. 157-166
Author(s):  
Nikki Hessell
Keyword(s):  
Medical Knowledge ◽  
John Keats ◽  
Specific Response ◽  
Medical Studies ◽  
Sources Of Information ◽  
Medical Practices ◽  
Traditional Medicines ◽  
Medical Imagery ◽  
Indian Medicine ◽  
The Impact

John Keats's medical studies at Guy's Hospital coincided with a boom in interest in both the traditional medicines of the sub-continent and the experiences of British doctors and patients in India. Despite extensive scholarship on the impact of Keats's medical knowledge on his poetry, little consideration has been given to Keats's exposure to Indian medicine. The poetry that followed his time at Guy's contains numerous references to the contemporary state of knowledge about India and its medical practices, both past and present. This essay focuses on Isabella and considers the major sources of information about Indian medicine in the Regency. It proposes that some of Keats's medical imagery might be read as a specific response to the debates about medicine in the sub-continent.

Transport and Chronic Injuries Caused by Improper Use of Cell Phones：Evidences from 41 Studies (Preprint)

2020 ◽  
Author(s):  
Xinxi Cao ◽  
Yangyang Cheng ◽  
Chenjie Xu ◽  
Yabing Hou ◽  
Hongxi Yang ◽  
...  
Keyword(s):  
Human Body ◽  
Cell Phone ◽  
Injury Risk ◽  
Negative Impact ◽  
Mental Disease ◽  
Cell Phones ◽  
Cell Phone Use ◽  
Improper Use ◽  
Chronic Injuries ◽  
The Impact

BACKGROUND Cell phone use brought convenience to people, but using phones for a long period of time or in the wrong way and with a wrong posture might cause damage to the human body. OBJECTIVE To assess the impact of improper cell phone use on transport and chronic injuries. METHODS Studies were systematically searched in PubMed, EMBASE, Cochrane, and Web of Science up to April 4, 2019 and relevant reviews were searched to identify additional studies. A random-effects model was used to estimate the overall pooled estimates. RESULTS Cell phone users were at a higher risk for transport injuries (RR: 1.37, 95%CI: 1.221.55), long-term use of cell phones increased the transport injury risk to non-use or short-term use (RR: 2.10, 95% CI: 1.632.70). Neoplasm risk caused by cell phone use was 1.07 times that of non-use (95% CI: 1.011.14); Compared with non-use, cell phone use had a higher risk of eye disease, with a risk of 2.03 (95% CI: 1.273.23), the risk of mental disease was 1.26 (95% CI: 1.171.35), the risk of neurological disorder was 1.16 (95% CI: 1.021.32), and a pooled risk of other chronic injuries was 1.20 (95% CI: 0.981.59). CONCLUSIONS Cell phone use at inappropriate situations has a negative impact on the human body. Therefore, it is necessary to use cell phones correctly and reasonably.

Effect of alkali therapy with NaHCO3 or THAM on cardiac contractility

1996 ◽  
Vol 270 (5) ◽  
pp. R955-R962
Author(s):  
C. D. Mazer ◽  
B. Naser ◽  
K. S. Kamel
Keyword(s):  
Myocardial Ischemia ◽  
Contractile Function ◽  
Venous Blood ◽  
Systolic Pressure ◽  
Ischemic Myocardium ◽  
Stroke Work ◽  
Length Relationship ◽  
Alkali Therapy ◽  
Myocardial Contractile ◽  
The Impact

We examined the impact of alkali therapy on myocardial contractility in a model of myocardial ischemia in dogs using direct measurements of myocardial contractile function. Myocardial ischemia in the left anterior descending (LAD) artery territory was induced using a perfusion circuit from the internal carotid artery to the LAD artery. Myocardial contractile function was assessed using sonomicrometry for measurement of percent systolic shortening (%SS), preload recruitable stroke work (PRSW) slope, and end-systolic pressure-length relationship (ESPLR) area. Because the blood flow in LAD artery was diminished by approximately 70%, there was a significant decrease in O2 delivery and uptake by the ischemic myocardium. Ischemia led to a significant fall in LAD regional contractile function with %SS decreasing from 15 +/- 2 to 7 +/- 2%, PRSW slope from 82 +/- 10 to 37 +/- 5 mmHg, and ESPLR area from 121 +/- 2 to 48 +/- 14 mmHg.mm (P < 0.05). In six dogs, the intracoronary administration of NaHCO(3) resulted in a significant increase in pH in LAD arterial and venous blood. There was, however, no significant increase in %SS (6 +/- 2), PRSW slope (43 +/- 10 mmHg), or ESPLR area (60 +/- 13 mmHg.mm). Since administration of NaHCO(3) resulted in a significant increase in PCO2 in LAD arterial and venous blood, similar experiments were carried out in five dogs, but with the intracoronary infusion of the amine buffer THAM [tris(hydroxymethyl)aminomethane (Tris) buffer; 2-amino-2-hydroxyl-1,3-propandiol] instead of NaHCO3. Although administration of THAM resulted in a significant increase in pH and a significant decrease in PCO2, in both LAD arterial and venous blood, there was no significant improvement in any of the parameters used to assess myocardial contractile function. In conclusion, administration of alkali (NaHCO3 or THAM) does not enhance the contractile function of the ischemic myocardium.

scholarly journals Development of an electronic conversation aid to support shared decision making for children with acute otitis media

JAMIA Open ◽  
2021 ◽  
Vol 4 (2) ◽  
Author(s):  
Jana L Anderson ◽  
e Silva Lucas Oliveira J ◽  
Juan P Brito ◽  
Ian G Hargraves ◽  
Erik P Hess
Keyword(s):  
Decision Making ◽  
Shared Decision Making ◽  
Otitis Media ◽  
Acute Otitis Media ◽  
Medical Knowledge ◽  
Complication Rates ◽  
Shared Decision ◽  
Web Based ◽  
Quality Issue ◽  
The Impact

Abstract Objective The overuse of antibiotics for acute otitis media (AOM) in children is a healthcare quality issue in part arising from conflicting parent and physician understanding of the risks and benefits of antibiotics for AOM. Our objective was to develop a conversation aid that supports shared decision making (SDM) with parents of children who are diagnosed with non-severe AOM in the acute care setting. Materials and Methods We developed a web-based encounter tool following a human-centered design approach that includes active collaboration with parents, clinicians, and designers using literature review, observations of clinical encounters, parental and clinician surveys, and interviews. Insights from these processes informed the iterative creation of prototypes that were reviewed and field-tested in patient encounters. Results The ear pain conversation aid includes five sections: (1) A home page that opens the discussion on the etiologies of AOM; (2) the various options available for AOM management; (3) a pictograph of the impact of antibiotic therapy on pain control; (4) a pictograph of complication rates with and without antibiotics; and (5) a summary page on management choices. This open-access, web-based tool is located at www.earpaindecisionaid.org. Conclusions We collaboratively developed an evidence-based conversation aid to facilitate SDM for AOM. This decision aid has the potential to improve parental medical knowledge of AOM, physician/parent communication, and possibly decrease the overuse of antibiotics for this condition.

scholarly journals Prevalence of SARS-CoV-2 Infection at the University of Barcelona during the Third COVID-19 Pandemic Wave in Spain

2021 ◽  
Vol 18 (12) ◽  
pp. 6526
Author(s):  
Sebastián Videla ◽  
Aurema Otero ◽  
Sara Martí ◽  
M. Ángeles Domínguez ◽  
Nuria Fabrellas ◽  
...  
Keyword(s):  
Ad Hoc ◽  
Venous Blood ◽  
Herd Immunity ◽  
Cross Sectional Study ◽  
Rt Pcr ◽  
Igg Antibody ◽  
Cross Sectional ◽  
Total Prevalence ◽  
The University ◽  
The Impact

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic started in December 2019 and still is a major global health challenge. Lockdown measures and social distancing sparked a global shift towards online learning, which deeply impacted universities’ daily life, and the University of Barcelona (UB) was not an exception. Accordingly, we aimed to determine the impact of the SARS-CoV-2 pandemic at the UB. To that end, we performed a cross-sectional study on a sample of 2784 UB members (n = 52,529). Participants answered a brief, ad hoc, online epidemiological questionnaire and provided a nasal swab for reverse transcription polymerase chain reaction (RT-PCR) SARS-CoV-2 analysis and a venous blood sample for SARS-CoV-2 IgG antibody assay. Total prevalence of SARS-CoV-2 infection (positive RT-PCR or positive IgG) was 14.9% (95%CI 13.3 to 17.0%). Forty-four participants (1.6%, 95%CI: 1.2–2.1%) were positive for SARS-CoV-2 RT-PCR. IgG against SARS-CoV-2 was observed in 12.8% (95%CI: 11.6–14.1%) of participants. Overall, while waiting for population vaccination and/or increased herd immunity, we should concentrate on identifying and isolating new cases and their contacts.

Sign in / Sign up

Export Citation Format

Share Document