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Nathan Goodyear

Chronic stress impacts the cardiovascular system: animal models and clinical outcomes |... - 0 views

ajpheart.physiology.org/...H1476

chronic stress stress inflammation cardiovascular disease atherosclerosis NO nitric oxide oxidative stress cardiovascular heart

shared by Nathan Goodyear on 03 Sep 17 - No Cached
  • Nathan Goodyear on 03 Sep 17
     
    Chronic stress increases cardiovascular disease.  Of note, chronic stress reduces eNOS activity and NO bioavailability, increased lipid oxidation (oxLDL) via a reduction in antioxidant protection, increased pro-inflammatory cytokines, increased thrombosis and clotting risk, increased blood pressure and reduced HRV.
Nathan Goodyear

Resurgence of Persisting Non-Cultivable Borrelia burgdorferi following Antibiotic Treat... - 0 views

journals.plos.org/...article

lyme Lyme disease borrelia burgdorferi

shared by Nathan Goodyear on 14 Dec 17 - No Cached
  • Experimental animal studies have shown that Borrelia burgdorferi, the agent of Lyme borreliosis, consistently establishes persistent infections in a variety of immunocompetent hosts, including laboratory mice [1], white-footed mice (Peromyscus leucopus) [2], [3], [4], rats [5], hamsters [6], guinea pigs [7], gerbils [8], dogs [9], and nonhuman primates, including rhesus macaques (Macaca mulatta) [10] and baboons (Papio spp.
  • With the advent of PCR, and more recently real-time quantitative PCR (qPCR), which offers greater sensitivity and specificity, B. burgdorferi-specific DNA has been found to persist for months following antibiotic treatment in tissues of experimentally infected mice [14], [15], [16], [17], [18], [19], [20], dogs [9], [21] and macaques [22], as well as humans
  • In addition, intact spirochetes have been demonstrated by immunohistochemistry in connective tissue of culture-negative treated mice and within ticks that fed upon them [15], [17] as well as in tissues of and ticks that fed upon treated macaques
  • ...1 more annotation...
  • Results of this study demonstrated not only persistence, but also resurgence of non-cultivable B. burgdorferi in tissues of mice at up to 12 months following antibiotic treatment
  • Nathan Goodyear on 14 Dec 17
     
    mouse model using ceftriaxone treatment regimen found that non-cultivatable B. burgdorferia persisted 8+ months post treatment and there was an increase in B. burgdorferi DNA in multiple sites at 12 months.
Nathan Goodyear

The acute effect of high-dose intravenous vitamin C and other nutrients on blood pressu... - 0 views

www.ncbi.nlm.nih.gov/...PMC4864764

vitamin C IV vitamin C hypertension vitamin B12 blood pressure cardiovascular disease CVD

shared by Nathan Goodyear on 14 Aug 17 - No Cached
  • the reduction in BP within the first 10–20 min may be primarily attributed to a direct vasodilatory physiological effect, described as venodilation
  • BP reduction observed after 70–90 min is likely attributable to pharmacokinetically plausible vitamin C absorption and vasodilation because of nitric oxide release
  • Pharmacokinetic studies of IVC administration observed peak plasma levels within the first 90 min, with plasma levels reaching 13350 μmol/l for 50 g of IVC
  • ...6 more annotations...
  • Essential hypertension, associated with endothelial dysfunction because of an impaired nitric oxide/l-arginine pathway and impaired vasodilation can be restored by vitamin C
  • marked increase in BP response when IVB12 is administered
  • The mean BP increased significantly up to 12–16 mmHg systolic and diastolic independent of the dosage of vitamin B12
  • The production of norepinephrine, which can stimulate angiotensin-II production, which in turn influences BP, has been suggested as a possible mechanism for the increase in BP with IVB12
  • excess norephinephrine levels stimulate the sympathetic nervous system, leading to increased cortisol production, which has also been linked to increases in BP
  • Animal studies have found higher serum levels of norepinephrine (noradrenaline) in the adrenal medulla of rats receiving methylcobalamin (methyl-vitamin B12)
  • Nathan Goodyear on 14 Aug 17
     
    IV vitamin C in mostly normotensive patients (> 30 grams) reduced blood pressure.  Some of the patients were pre-hypertensive. Vitamin B12 increase the blood pressure.
Nathan Goodyear

Low-dose Interleukin-2 in the Treatment of Autoimmune Disease | touchONCOLOGY - 0 views

www.touchoncology.com/...2-treatment-autoimmune-disease

cancer autoimmune disease Tregs Treg cells Treg immune system disease IL-2

shared by Nathan Goodyear on 04 Apr 18 - No Cached
Amol kashikar liked it
  • affect approximately 5 to 8 % of the US population
  • the incidence and prevalence of autoimmune diseases are rising
  • Type 1 diabetes (T1D), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and inflammatory bowel disease (IBD) account for the majority of the patients with autoimmune diseases
  • ...9 more annotations...
  • Autoimmune diseases are characterized by a breakdown of mechanisms that allow the immune system to distinguish between self and nonself and maintain immunologic self-tolerance
  • Tregs, which are important in the maintenance of peripheral immune tolerance.
  • Several subtypes of Tregs exist, the most well studied being CD4+ cells that express high-level CD25 and the transcription factor forkhead box P3 (FOXP3)
  • Treg deficiency or dysfunction is associated with autoimmune disease
  • In clinical studies, decreased levels of circulating CD25+CD4+ T cells have been reported in patients with autoimmune disease
  • These data have led to the hypothesis that augmentation of Tregs may be a useful therapeutic strategy in autoimmune disease
  • Treg augmentation has resulted in clinical improvements in numerous animal models of autoimmune diseases
  • the administration of in vitro expanded CD4+CD25highCD127-Tregs has been found to be safe and may help to preserve β-cell function in children with T1D
  • ability of IL-2 to augment the numbers and function of CD4+ Tregs.
  • Nathan Goodyear on 04 Apr 18
     
    Great article.  Immune dysfunction plays role in autoimmune disease and cancer.  Treg cells sit at the center of autoimmunity.  This artice highlights the different uses: low dose IL2 therapy to augment Tregs and reduce autoinflammation and high dose IL2 to augment Treg cells in the fight against cancer.
Nathan Goodyear

Tumor regionalization after surgery: Roles of the tumor microenvironment and neutrophil... - 0 views

www.nature.com/...s12276-022-00784-2

TME NETosis metastasis surgery cancer tumor microenvironment

shared by Nathan Goodyear on 20 Apr 23 - No Cached
  • tumor surgery must be carefully considered because the risk of metastasis could be increased by the surgical procedure.
  • NETosis, which is the process of forming neutrophil extracellular traps (NETs)
  • surgery-induced metastasis
  • ...61 more annotations...
  • surgery per se can promote cancer metastasis through a series of local and systemic events
  • surgery results in a serious wound that disrupts the structural barrier preventing the outspreading of cancer cells, change the properties of the cancer cells and stromal cells remaining in the tumor microenvironment, or impairs the host defense systems against cancers
    • Nathan Goodyear
      Nathan Goodyear on 23 Apr 23
       
      Key point; add to presentation on surgery and metastasis
  • After the primary tumor is surgically removed, the metastases can start to grow vigorously via neoangiogenesis because the circulating inhibitors disappear
  • infection and inflammation during the postoperative period have been reported to increase the risk of cancer recurrence in patients
  • Surgeons have long suspected that surgery, even if it is a necessary step in cancer treatment, facilitates cancer metastasis
  • Surgery-induced cancer metastasis has been well established in animal models
  • tumor cell dissemination, tumor-favoring immune responses, and neoangiogenesis
  • the surgical resection of primary tumors is beneficial is controversial
  • CTCs abruptly increase just after surgery
  • Even externally palpitating tumors for diagnosis could increase the numbers of CTCs in skin cancer and breast cancer
  • excessive glucocorticoids negatively modulate immune functions
  • immune surveillance against tumors is considered to be impaired by surgical stress
  • In addition to glucocorticoids, during stimulation of the HPA axis, the catecholamine hormones epinephrine and norepinephrine are released from the adrenal medulla
  • NK cell suppression may be attributed to increased levels of catecholamines as well as glucocorticoids
  • In mice bearing a primary tumor, it was observed that the removal of the primary tumor facilitated the growth of highly vascularized metastases
  • primary tumors may secrete angiogenic inhibitors as well as angiogenic activators
  • second phase of tumor recurrence and metastasis, which are newly acquired events, rather than just outcomes of incomplete treatment.
    • Nathan Goodyear
      Nathan Goodyear on 23 Apr 23
       
      Another key point
  • double-edged sword
  • HIF-1 in neutrophils plays a critical role in NETosis and bacteria-killing activity
  • neutrophils play various roles in the initiation and progression of cancer
  • NETosis
  • many inflammatory and neoplastic diseases
  • formation of neutrophil extracellular traps (NETs), which are large extracellular complexes composed of chromatin and cytoplasmic/granular proteins1
  • NETosis has been highlighted as an inflammatory event that promotes cancer metastasis
  • Once activated, neutrophils produce intracellular precursors by using DNA, histones, and granular and cytoplasmic proteins and then spread the mature form of NETs out around themselves
  • A series of these events is called NETosis.
  • neutrophil elastase, myeloperoxidase, cathepsin G, proteinase 3, lactoferrin, gelatinase, lysozyme C, calprotectin, neutrophil defensins, and cathelicidins
  • innate immune response against infection
  • Neutrophils are the most abundant type of granulocytes, comprising 40–70% of all white blood cells
  • two types of NEToses, suicidal (or lytic) NETosis and vital NETosis
  • Suicidal NETosis mainly depends on the production of reactive oxygen species (ROS)
  • Since neutrophils die during this process, it is called suicidal NETosis.
  • vital NETosis
  • vital NETosis occurs independently of ROS production
  • Vital NETosis can be induced by Gram-negative bacteria. LPS
  • NETs are present in a variety of cancers, such as lung cancer, colon cancer, ovarian cancer, and leukemia
  • neutrophils actively undergo NETosis in the tumor microenvironment
  • Hypoxia
  • NETosis plays a pivotal role in noninfectious autoimmune diseases,
  • cytokines
  • tumor-derived proteases
  • tumor exosomes
  • NETosis generally actively progresses in the tumor microenvironment.
  • the proliferative cytokines TGFβ and IL-10 and the angiogenic factor VEGF are representative of neutrophil-derived tissue repair proteins.
  • NETosis is a defense system to protect the body from invading pathogens
  • when neutrophils are excessively stimulated, they produce excess NETs, thereby leading to pathological consequences
  • plasma levels of NETosis markers are elevated after major surgeries
  • local invasion, intravasation into the blood or lymphatic vessels, escape from the immune system, anchoring to capillaries in target organs, extravasation into the organs, transformation from dormant cells to proliferating cells, colonization to micrometastases, and growth to macrometastases
  • NETs promote metastasis at multiple steps
  • NETs loosen the ECM and capillary wall to promote the intravasation of cancer cells
  • NETs and platelets wrap CTCs, which protects them from attack by immune cells and shearing force by blood flow
  • NETs promote the local invasion of cancer cells by degrading the extracellular matrix (ECM)
  • neutrophil elastase, matrix metalloproteinase 9, and cathepsin G
  • NETs also promote the intravasation of cancer cells
  • millions of tumor cells are released into the circulation every day,
  • NETs can wrap up CTCs with platelets
  • β1-integrin plays an important role in the interaction between CTCs and NETs
  • NET-platelet-CTC aggregates.
  • After metastasizing to distant tissues, tumor cells are often found to remain dormant for a period of time and unexpectedly regrow late
  • NETs are believed to participate in the reactivation of dormant cancer cells in metastatic regions
  • NET-associated proteases NE and MMP-9 were found to be responsible for the reactivation of dormant cancer cells
  • Nathan Goodyear on 20 Apr 23
     
    Surgery induced metastasis: it is real and steered by NETosis.
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