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Nathan Goodyear

Circulating Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Vaccine Antige... - 0 views

academic.oup.com/...6279075

COVID-19 COVID SARS-CoV-2 covid19 spike protein

shared by Nathan Goodyear on 07 Sep 21 - No Cached
  • Nathan Goodyear on 07 Sep 21
     
    Spike proteins reach blood stream in 11/13 vaccinated. The implications on the endothelium and myocardium is significant.
Nathan Goodyear

Rebuilding the post-infarcted myocardium by a... [Heart Fail Rev. 2010] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...18773293

thyroid MI myocardial infarction heart attack hormone hormones post-MI heart cardiac remodeling

shared by Nathan Goodyear on 03 Jul 12 - No Cached
  • Nathan Goodyear on 03 Jul 12
     
    Wow, thyroid hormones play a significant role in cardiac remodeling post MI.  Thyroid hormones, "promotes tissue growth and differentiation and favorably remodels cardiac cell while increases cellular survival..."  How many people post-MI are having their thyroid evaluated, let alone correctly evaluated?
Nathan Goodyear

Long-term benefits of testosterone replacement therapy on angina threshold and atheroma... - 0 views

eje-online.org/...443.long

low Testosterone low T heart myocardium ischemia men male testosterone hormone hormones

shared by Nathan Goodyear on 17 Jul 12 - No Cached
  • Nathan Goodyear on 17 Jul 12
     
    Testosterone therapy in men prolongs time to myocardial ischemia.  The follow of this study was 12 months and the number of men was small (15 men).  This was continually therapy during the duration of 12 months.
Nathan Goodyear

Acute Anti-Ischemic Effect of Testosterone in Men With Coronary Artery Disease - 0 views

circ.ahajournals.org/...1666.full

low T low Testosterone CAD CVD testosterone artery dilation heart myocardium myocardial ischemia cardiology men male hormone hormones

shared by Nathan Goodyear on 17 Jul 12 - No Cached
  • Nathan Goodyear on 17 Jul 12
     
    Testosterone shown to have vasodilatory effect in men.  In this small study, the short course of IV testosterone reduced exercise induced heart ischemia.  This was in men with pre-existing CAD.
Nathan Goodyear

Exercise-induced right ventricular dysfunction and structural remodelling in endurance ... - 0 views

eurheartj.oxfordjournals.org/...998

endurance athletes training heart health injury

shared by Nathan Goodyear on 09 Jan 15 - No Cached
  • In a cohort of well-trained athletes, we demonstrated that intense endurance exercise causes an acute reduction in RV function that increases with race duration and correlates with increases in biomarkers of myocardial injury
  • no relationship between LV function and biomarker levels
  • focal gadolinium enhancement and increased RV remodelling were more prevalent in those athletes with a longer history of competitive sport, suggesting that repetitive ultra-endurance exercise may lead to more extensive RV change and possible myocardial fibrosis
  • ...22 more annotations...
  • he cardiac impact of both acute and cumulative exercise is greatest on the RV.
  • Greater reductions in RV function occurred in those athletes competing for a longer duration, suggesting that the heart has a finite capacity to maintain the increased work demands of exercise
  • cardiac injury is greatest in the least trained
  • Previous investigators have documented reductions in RV function in less trained subjects over the marathon distance
  • We enrolled elite and subelite athletes and found a significant association between fitness (VO2max) and the reduction in post-race RVEF
  • Even after many years of detraining, cardiac dilation may not completely regress in elite athletes
  • The focus on well-trained athletes may be of particular relevance, given that they perform exercise of highest intensity and duration most frequently, and, thus, may be at a greater risk of cumulative injury.
  • The lack of correlation between increases in troponin and changes in LV function seen in this study has been previously interpreted as evidence that post-exercise elevations in cardiac biomarkers are benign.
  • a significant correlation between changes in RVEF and post-race biomarker levels and this relationship was even stronger in the athletes who completed the race of longest duration, the ultra-triathlon
  • The correlations with RVEF, but not LVEF, provide further evidence of the differential effects of intense exercise on RV and LV function
  • BNP release during intense exercise is associated with greater relative increases in RV systolic pressures, but not LV pressures
  • BNP may provide a measure of both acute RV load and the resultant fatigue which occurs when this load is sustained
  • It has been demonstrated that ventricular load increases with exercise intensity and is greater for the RV than the LV,29 thus potentially explaining why the RV is more susceptible to fatigue after prolonged exercise.
  • This study demonstrates, for the first time, an association between endurance exercise of increasing duration and structural, functional, and biochemical markers of cardiac dysfunction in highly trained athletes
  • Functional abnormalities were confined to the RV and were largely reversible 1 week following the event
  • there remained a significant minority of athletes in whom there was evidence of myocardial fibrosis in the interventricular septum
  • RV abnormalities may be acquired through cumulative bouts of intense exercise and provides direction for prospective investigations aimed at elucidating whether extreme exercise may promote arrhythmias in some athletes.
  • the acute injury and chronic remodelling of the myocardium both disproportionately affect the RV and it remains possible that the two are linked.
  • focal DGE was confined to the interventricular septum and commonly at the site of RV attachment
  • emerging evidence that intense endurance exercise may be associated with an excess in arrhythmic disorders, the mechanisms for which remain unexplained
  • RVEF (and not LVEF) was reduced in athletes with complex ventricular arrhythmias when compared with healthy athletes and non-athletes without arrhythmias
  • it is premature to conclude that these changes may represent a proarrhythmic substrate
  • Nathan Goodyear on 09 Jan 15
     
    Study finds endurance racing results in reduce Right ventricle ejection fraction even in elite athletes.  This post-race RVEF reduction is associated with VO2max.
Nathan Goodyear

Cellular and Molecular Basis of Deiodinase-Regulated Thyroid Hormone Signaling - 0 views

www.ncbi.nlm.nih.gov/...PMC2647704

thyroid hormone T3 T4 rT3 deiodinase selenium hormones

shared by Nathan Goodyear on 10 Nov 14 - No Cached
  • Nathan Goodyear on 10 Nov 14
     
    Anything and everything one would want to know regarding thyroid hormone signaling.  Doctors, especially endocrinologists, need to read this.  T4 is not or is ever inside target cells.  The enzymes, deiodinase types 1, 2, and 3, are what control the thyroid hormone at the cellular levels.  Deiodinase-2 is what generates T3 in the cytosol of the cell.  In contrast, deiodinase-3 is what generates rT3 which is inactive.  High Fat diet increases deiodinase-3.
Nathan Goodyear

Late Disseminated Lyme Disease: Associated Pathology and Spirochete Persistence Post-Tr... - 0 views

ajp.amjpathol.org/...fulltext

Lyme Lyme disease borrelia burgdorferi

shared by Nathan Goodyear on 14 Dec 17 - No Cached
  • In this study, we have demonstrated microscopic pathology ranging from minimal to moderate in multiple different tissues previously reported to be involved with LD, including the nervous system (central and peripheral), heart, skeletal muscle, joint-associated tissues, and urinary bladder 12 to 13 months following tick-inoculation of rhesus macaques by Bb strain B31
  • Based on histomorphology, inflammation consisted predominantly of lymphocytes and plasma cells, with rare scattered histiocytes
  • in rare instances, morphologically intact spirochetes were observed in inflamed brain and heart tissue sections from doxycycline-treated animals
  • ...41 more annotations...
  • colocalization of the Bb 23S rRNA probe was not observed in any of the sections of experimental inoculated animals shown to harbor rare persistent spirochetes (Supplemental Figure S1). Previous in vitro work has shown large decreases in Bb rRNA levels when in a stationary phase of growth despite the majority of spirochetes remaining viable
  • The possibility that the spirochetes were intact but dead also exists, though this may be unlikely given the precedence for viable but non-cultivable B. burgdorferi post-treatment
  • The doxycycline dose utilized in this study (5mg/kg) was based on a previous pharmacokinetic analysis of oral doxycycline in rhesus macaques proven to be comparable to levels achieved in humans and was meant to mimic treatment of disseminated LD
  • In addition to the brain of two treated animals, rare morphologically intact spirochetes immunoreactive to OspA were observed in the heart of one treated animal
  • Although we did not measure the doxycycline levels in the cerebrospinal fluid, they have been found to be 12% to 15% of the amount measured in serum
  • We and others have demonstrated the development of a drug-tolerant persister population when B. burgdorferi are treated with antibiotics in vitro
  • The adoption of a dormant or slow-growing phenotype likely allows the spirochetes to survive and re-grow following removal of antibiotic
  • The basic premise that antibiotic tolerance may be an adaptation of the sophisticated stringent response required for the enzootic cycle by the spirochetes is described in a recent review as well
  • Although current IDSA guidelines recommend intravenous ceftriaxone (2g daily for 30 days) over oral doxycycline for treatment of neuroborreliosis, a randomized clinical trial failed to show any enhanced efficacy of I.V. penicillin G to oral doxycycline for treatment of Lyme neuroborreliosis (no treatment failures were reported in this study of 54 patients).
  • we can speculate that the minimal to moderate inflammation that was observed, especially within the CNS and PNS can, in part, explain the breadth of symptoms experienced by late stage Lyme disease patients, such as cognitive impairment and neuralgia.
  • Erythema migrans, the clinical hallmark of early localized Lyme disease, was observed in one of the rhesus macaques from this study.
  • In 2014, a trailblazing study in mice demonstrated a dramatic decline in B. burgdorferi DNA in the tissues for up to eight months after antibiotic treatment followed by the resurgence of B. burgdorferi growth 12 months after treatment
  • This study provides evidence that the slow-growing spirochetes which persist after treatment, but are not cultivable in standard growth media may remain viable.
  • The first well-documented indication of Lyme disease (LD) in the United States occurred in the early 1970s
  • Lyme, Connecticut.
  • Lyme disease is now known to be caused by multiple closely related genospecies classified within the Bb sensu lato complex, representing the most common tick-borne human disease in the Northern Hemisphere
  • approximately 30,000 physician-reported cases occur annually in the United States, the annual incidence has been estimated to be 10-fold higher by the Centers for Disease Control and Prevention.6
  • Current antibiotic therapy guidelines outlined by the Infectious Disease Society of America (IDSA) are successful in the treatment of LD for the majority of LD patients, especially when administered early in disease immediately following identification of erythema migrans (EM)
  • ‘post-treatment Lyme disease syndrome’ (PTLDS)
  • host-adapted spirochetes that persist in the tissues, probably in small numbers, inaccessible or impervious to antibiotic
  • inflammatory responses to residual antigens from dead organisms
  • residual tissue damage following pathogen clearance;
  • autoimmune responses, possibly elicited by antigenic mimicry
  • Experimental studies on immunocompetent mice, dogs, and rhesus macaques have provided evidence for the persistence of Bb spirochetes subsequent to antibiotic treatment in the form of residual spirochetes detected within tissue by IFA and PCR, and recovered by xenodiagnoses
  • Ten male rhesus macaques
  • half (five) of the NHP received antibiotic treatment, consisting of 5 mg/kg oral doxycycline twice per day.
  • Minimal and focal lymphoplasmacytic inflammation
  • inflammation was observed in the leptomeninges overlying a section of temporal cerebral cortex
  • Minimal localized lymphoplasmacytic choroiditis
  • Peripheral nerves contained minimal to moderate lymphoplasmacytic inflammation with a predilection for collagen-rich epineurium and perivascular spaces
  • Inflammation was observed in 56% (5/9) of the NHPs irrespective of treatment group
  • For all animals, inflammation was reserved to perineural tissue
  • The treatment lasted 28 days
  • Minimal to mild lymphoplasmacytic inflammation of either the myocardial interstitium (Figure 2Figure 2A), pericardium (Figure 2Figure 2B), or combination therein was observed in 60% of NHPs
  • A single morphologically intact spirochete, as indicated by positive red immunofluorescence (Figure 2Figure 2C), was observed in the myocardium of one treated animal
  • mild, multifocal lymphoplasmacytic inflammation was observed in one doxycycline-treated animal
  • three animals exhibited minimal to mild lymphoplasmacytic inflammation affecting joint-associated structures
  • 10% to -20% of human patients treated
  • Multiple randomized placebo-controlled studies which evaluated sustained antimicrobial therapy concluded that there is no benefit in alleviating patients’ symptoms and indicated that long-term antibiotic therapy may even be detrimental to patients due to potential associated complications (ie, catheter infection and/or clostridial colitis)
  • and the rapid clearance of dead spirochetes in a murine model
  • higher doses may be needed to combat neuroborreliosis
  • Nathan Goodyear on 14 Dec 17
     
    persistent borrelia burgdorferia were found in the brain (2) and the heart (1) up to 13 months post standard antibiotic treatment suggesting borrelia burdorferia, the cause of Lyme, can persist in a chronic, persistant state poste acute treatment.
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