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37-614: Surgical Neurology International was established in April 2010 by James I. Ausman , the longtime and last editor of Surgical Neurology . The journal is abstracted and indexed in Pubmed Central and Scopus . The journal regularly publishes supplements organized around a common theme. Recent issues have covered neuro-oncology , new developments in neurosurgery, stereotactic techniques, spine , neurovascular, neuro-nursing, and pediatric neurosurgery. The journal collaborates with

74-731: A Christian author and fellow surgeon: "Patients come first... treat the patient as yourself... do not let yourself fall asleep until you are certain you have done everything for your patient." Ausman is an honorary member of the Brazilian, Argentinean, Chilean, and Peruvian Societies of Neurosurgery and a corresponding member of the German Society of Neurosurgery. Through his James I and Carolyn R. Ausman Educational Foundation and his vehicle, Surgical Neurology International, Rancho Mirage, California, Ausman has recently expanded his humanitarian and educational mission, in particular highlighting

111-628: A selective BBB is operative at birth. In mice, Claudin-5 loss during development is lethal and results in size-selective (upto 742Da) loosening of the BBB. Mosaic deletion of claudin-5 in adult endothelial cells (in mice) reveals BBB leakage upto 10kDa molecule 6 days after deletion of claudin-5 and lethality after 10 days after deletion demonstrating a critical role of Claudin-5 in adult BBB. The blood–brain barrier acts effectively to protect brain tissue from circulating pathogens and other potentially toxic substances. Accordingly, blood-borne infections of

148-438: A sensory organ. The blood–brain barrier is formed by the brain capillary endothelium and excludes from the brain 100% of large-molecule neurotherapeutics and more than 98% of all small-molecule drugs. Overcoming the difficulty of delivering therapeutic agents to specific regions of the brain presents a major challenge to treatment of most brain disorders. In its neuroprotective role, the blood–brain barrier functions to hinder

185-408: Is a function of the choroidal cells of the choroid plexus , and from the blood-retinal barrier , which can be considered a part of the whole realm of such barriers. Not all vessels in the human brain exhibit BBB properties. Some examples of this include the circumventricular organs , the roof of the third and fourth ventricles , capillaries in the pineal gland on the roof of the diencephalon and

222-424: Is a highly selective semipermeable border of endothelial cells that regulates the transfer of solutes and chemicals between the circulatory system and the central nervous system , thus protecting the brain from harmful or unwanted substances in the blood . The blood–brain barrier is formed by endothelial cells of the capillary wall , astrocyte end-feet ensheathing the capillary, and pericytes embedded in

259-422: Is composed of endothelial cells restricting passage of substances from the blood more selectively than endothelial cells of capillaries elsewhere in the body. Astrocyte cell projections called astrocytic feet (also known as " glia limitans ") surround the endothelial cells of the BBB, providing biochemical support to those cells. The BBB is distinct from the quite similar blood-cerebrospinal fluid barrier , which

296-514: Is essential for peace and civilization and that All Lives Matter and that Truth Matters! These seminars have been provided online, worldwide, for free to physicians and patients via his publication, Surgical Neurology International. Ausman has recently co-authored the book The China Virus – What is the Truth? with Russell L. Blaylock ( ISBN   979-8522503246 self-published). Blood%E2%80%93brain barrier The blood–brain barrier ( BBB )

333-558: Is now a clinical professor of neurosurgery at the University of California at Los Angeles . Ausman has been called a "multitasker" due to his multiple endeavors. Ausman is the author of research articles published in medical journals. Frequent topics of these articles have been: Ausman is a pioneer in the field of revascularization techniques to improve cerebral blood flow , relieve cerebral ischemia , and treat cerebral infarction and has contributed articles and chapter books on

370-451: Is under preliminary research for its potential to facilitate the transfer of drugs across the BBB. Capillary endothelial cells and associated pericytes may be abnormal in tumors and the blood–brain barrier may not always be intact in brain tumors. Other factors, such as astrocytes , may contribute to the resistance of brain tumors to therapy using nanoparticles. Fat soluble molecules less than 400 daltons in mass can freely diffuse past

407-788: The National Institutes of Health , receiving a PhD in pharmacology from the George Washington University School of Medicine in 1969. He became a staff member at the University of Minnesota in 1972, eventually becoming an assistant professor of neurosurgery and pharmacology. In 1978, he was named Chairman of the Department of Neurosurgery at Henry Ford Hospital in Detroit. At this time, Ausman became secretary of The Society of Neurological Surgeons . In 1991, Ausman became professor and head of

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444-500: The Russian Neurosurgical Journal . James I. Ausman James Ivan Ausman (born December 10, 1937) is an American neurosurgeon , science editor, television broadcaster, medical entrepreneur, and public advocate on health-care reform. He currently is professor of neurosurgery at the University of California, Los Angeles and editor-in-chief of Surgical Neurology International . Ausman

481-477: The aniline dyes that were then widely used), the dye stained all of the organs of some kinds of animals except for their brains. At that time, Ehrlich attributed this lack of staining to the brain simply not picking up as much of the dye. However, in a later experiment in 1913, Edwin Goldmann (one of Ehrlich's students) injected the dye directly into the cerebrospinal fluid of animal brains. He found then

518-407: The cerebrospinal fluid , while allowing the diffusion of hydrophobic molecules (O 2 , CO 2 , hormones) and small non-polar molecules. Cells of the barrier actively transport metabolic products such as glucose across the barrier using specific transport proteins . The barrier also restricts the passage of peripheral immune factors, like signaling molecules, antibodies, and immune cells, into

555-433: The fourth ventricle or third ventricle in the brain, and are characterized by dense capillary beds with permeable endothelial cells unlike those of the blood–brain barrier. Included among CVOs having highly permeable capillaries are the area postrema , subfornical organ , vascular organ of the lamina terminalis , median eminence , pineal gland , and three lobes of the pituitary gland . Permeable capillaries of

592-472: The pineal gland . The pineal gland secretes the hormone melatonin "directly into the systemic circulation", thus melatonin is not affected by the blood–brain barrier. The BBB appears to be functional by the time of birth. P-glycoprotein , a transporter , exists already in the embryonal endothelium. Measurement of brain uptake of various blood-borne solutes showed that newborn endothelial cells were functionally similar to those in adults, indicating that

629-542: The Asociación Argentina de Neurocirugía, Sociedade Brasileira de Neurocirurgía, Sociedad Neurocirugía de Chile , Asociación Colombiana de Neurocirugía, Pakistan Society of Neurosurgeons, Federación Latinoamericana de Sociedades de Neurocirugía, and the Sociedad Española de Neurocirugía. Collaboration is also maintained with the following journals: Brazilian Neurosurgery , Neurocirugía Hoy , and

666-452: The BBB through lipid mediated passive diffusion. The blood–brain barrier may become damaged in certain neurological diseases , as indicated by neuroimaging studies of Alzheimer's disease , amyotrophic lateral sclerosis , epilepsy , ischemic stroke, and brain trauma , and in systemic diseases , such as liver failure . Effects such as impaired glucose transport and endothelial degeneration may lead to metabolic dysfunction within

703-455: The Department of Neurosurgery at the University of Illinois at Chicago . There he expanded his work in microsurgery, cerebrovascular surgery, particularly aneurysms, arteriovenous malformations, and bypassing cerebral ischemia. He has written and developed procedures for neuro-vascular surgery and novel approaches to the pineal region and midline tumors. He has over 200 publications and over 80 chapters in neurosurgical books to his credit. He

740-448: The NTS and arcuate nucleus—to receive blood signals which are then transmitted into neural output. The permeable capillary zone shared between the median eminence and hypothalamic arcuate nucleus is augmented by wide pericapillary spaces, facilitating bidirectional flow of solutes between the two structures, and indicating that the median eminence is not only a secretory organ, but may also be

777-591: The Venezuelan crisis. Ausman organized, at his expense, a Surgical Neurology International webinar: SNI Neurosurgery World Education Summit that took place June 5 & 6, 2021. And on July 28 he participated in another webinar organized by the Asian Congress of Neurological Surgeons in which he gave the first lecture, "The Most Important Lesson I Learned in Medicine." In this lecture, Ausman orated on

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814-410: The blocking of active efflux transporters such as p-glycoprotein . Some studies have shown that vectors targeting BBB transporters, such as the transferrin receptor , have been found to remain entrapped in brain endothelial cells of capillaries, instead of being ferried across the BBB into the targeted area. The brain can be targeted non-invasively via the nasal passage. The drugs that remain in

851-408: The blood of animals. Thus, in theory, the salts failed to enter the brain. Two years later, Max Lewandowsky may have been the first to coin the term "blood–brain barrier" in 1900, referring to the hypothesized semipermeable membrane. There is some debate over the creation of the term blood–brain barrier as it is often attributed to Lewandowsky, but it does not appear in his papers. The creator of

888-515: The blood–brain barrier and zones "open" to blood signals in certain CVOs contain specialized hybrid capillaries that are leakier than typical brain capillaries, but not as permeable as CVO capillaries. Such zones exist at the border of the area postrema— nucleus tractus solitarii (NTS), and median eminence— hypothalamic arcuate nucleus . These zones appear to function as rapid transit regions for brain structures involved in diverse neural circuits—like

925-450: The brain are rare. Infections of the brain that do occur are often difficult to treat. Antibodies are too large to cross the blood–brain barrier, and only certain antibiotics are able to pass. In some cases, a drug has to be administered directly into the cerebrospinal fluid where it can enter the brain by crossing the blood-cerebrospinal fluid barrier . Circumventricular organs (CVOs) are individual structures located adjacent to

962-581: The brain involve going either "through" or "behind" the BBB. Modalities for drug delivery to the brain in unit doses through the BBB entail its disruption by osmotic means, or biochemically by the use of vasoactive substances, such as bradykinin , or even by localized exposure to high-intensity focused ultrasound (HIFU) . Other methods used to get through the BBB may entail the use of endogenous transport systems, including carrier-mediated transporters, such as glucose and amino acid carriers, receptor-mediated transcytosis for insulin or transferrin , and

999-494: The brain, and an increased permeability of the BBB to proinflammatory factors, potentially allowing antibiotics and phagocytes to move across the BBB. However, in many neurodegenerative diseases, the exact cause and pathology remains unknown. It is still unclear whether the BBB dysfunction in the disease is a causative agent, a result of the disease, or somewhere in the middle. A 1898 study observed that low-concentration " bile salts " failed to affect behavior when injected into

1036-444: The capillary basement membrane . This system allows the passage of some small molecules by passive diffusion , as well as the selective and active transport of various nutrients, ions, organic anions, and macromolecules such as glucose and amino acids that are crucial to neural function. The blood–brain barrier restricts the passage of pathogens , the diffusion of solutes in the blood, and large or hydrophilic molecules into

1073-440: The central nervous system, thus insulating the brain from damage due to peripheral immune events. Specialized brain structures participating in sensory and secretory integration within brain neural circuits —the circumventricular organs and choroid plexus —have in contrast highly permeable capillaries. The BBB results from the selectivity of the tight junctions between the endothelial cells of brain capillaries, restricting

1110-420: The delivery of many potentially important diagnostic and therapeutic agents to the brain. Therapeutic molecules and antibodies that might otherwise be effective in diagnosis and therapy do not cross the BBB in adequate amounts to be clinically effective. To overcome this problem some peptides able to naturally cross the BBB have been widely investigated as a drug delivery system. Mechanisms for drug targeting in

1147-466: The history of civilization, as it relates to medical practice. He expounded on the patient-doctor relationship based on the Hippocratic Oath that establishes doctors should "first do not harm," premium non-nocere and its corollary related to the individual-based ethics of Hippocrates, that the patient always come first —omni pro agroto ("all for the patient"). Ausman further asserted that truth

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1184-477: The passage after mucociliary clearance, enter the brain via three pathways: (1) Olfactory nerve-olfactory bulb-brain; (2) Trigeminal nerve-brain; and (3) Lungs/ Gastrointestinal tract-blood–brain The first and second methods involve the nerves, so they use the neuronal pathway and the third is via systemic circulation. However, these methods are less efficient to deliver drugs as they are indirect methods. Nanotechnology

1221-536: The passage of solutes. At the interface between blood and the brain, endothelial cells are adjoined continuously by these tight junctions, which are composed of smaller subunits of transmembrane proteins , such as occludin , claudins (such as Claudin-5 ), junctional adhesion molecule (such as JAM-A). Each of these tight junction proteins is stabilized to the endothelial cell membrane by another protein complex that includes scaffolding proteins such as tight junction protein 1 (ZO1) and associated proteins. The BBB

1258-549: The sensory CVOs (area postrema, subfornical organ, vascular organ of the lamina terminalis) enable rapid detection of circulating signals in systemic blood, while those of the secretory CVOs (median eminence, pineal gland, pituitary lobes) facilitate transport of brain-derived signals into the circulating blood. Consequently, the CVO permeable capillaries are the point of bidirectional blood–brain communication for neuroendocrine function. The border zones between brain tissue "behind"

1295-770: The subject. Other research reports have referred to drug therapy of brain tumors, surgical anatomy of the optic nerve region, surgical approaches to the pineal region, management of midline tumors , nerve tissue ultrastructure, the blood–brain barrier and pericyte -endothelial gap-junctions. Ausman was editor-in-chief of Surgical Neurology from 1994 until 2009, when it ceased publication. In 2010, he became founding editor-in-chief of Surgical Neurology International. He travels frequently to developed and Third World countries to advise, lecture on neurosurgical trends and techniques, and teach ethics in humanitarian missions. Dr. Ausman taught him humanitarian principles central to medical ethics, according to Ramsis F. Ghaly, M.D.,

1332-560: The term may have been Lina Stern . Stern was a Russian scientist who published her work in Russian and French. Due to the language barrier between her publications and English-speaking scientists, this could have made her work a lesser-known origin of the term. All the while, bacteriologist Paul Ehrlich was studying staining , a procedure that is used in many microscopy studies to make fine biological structures visible using chemical dyes. As Ehrlich injected some of these dyes (notably

1369-653: Was born in Milwaukee on December 10, 1937. He is married, and has two daughters. He attended Milwaukee County Day School, obtained a BSc degree from Tufts University in 1959, and graduated as an M.D. from Johns Hopkins Medical School three years later. In 1964, he received a Master's Degree in physiology at the State University of New York at Buffalo, after which he pursued surgery and neurosurgery training in Chicago and Minnesota . He then moved to

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