Skip to main content

Home/ Dr. Goodyear/ Group items tagged pathology

Rss Feed Group items tagged

Nathan Goodyear

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

  • 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
  •  
    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.
Nathan Goodyear

https://dl-web.dropbox.com/get/Public/Research/ane_7212-1.pdf?w=AABZMjLPg8k92S9AxmjD0IN... - 0 views

  •  
    Good non biased look at heavy metals, particularly Hg, and autism.  The authors of this study found the same neurologic pathology biochemically in Hg poisoning as in autism.  
Nathan Goodyear

Brain dopamine and obesity : The Lancet - 0 views

  •  
    Dopamine found to be inversely associated with BMI.  The higher the BMI, the lower the dopamine levels.  This low dopamine would result in a proposed "pathological eating".  As dopamine is the "pleasure" neurotransmitter, it would be easy to see how low dopamine would result in overeating.
wheelchairindia9

Cervical Collar Hard Adjustable With Chin - 0 views

  •  
    The soft cervical collar is constructed of foam rubber and covered with a stockinette material. Normally, the closure is achieved with Velcro. Depending on the patient's pathology and body structure, physician and/or orthotist will determine the proper height of the collar. When worn, the soft cervical collar is a reminder to keep in head and neck in a restricted position. It is the mildest design of cervical immobilization. Cervical collars are applied to blunt trauma patients all the time. And most of the time, the neck is fine. It's just those few patients that have fracture or ligamentous injury that really need it. The Cervical Collar provides firm, comfortable support which helps to relieve neck discomfort while providing extra support. Cervical Collar has a convenient hook and loop closure which allows the unit to be adjusted for a proper fit. The Cervical Collar is constructed of soft, porous cotton cover for comfort which is over polyfoam for the best support. Cervical collars are an orthotic device used primarily in the treatment of neck injuries and strains. The most common use of cervical collars is during recovery after surgery on the cervical spine. They are also used in whiplash injuries and conditions like Cervical Radiculopathy, which is caused by the nerves in the neck compressing due to herniated disks in the spinal cord. The main function of the cervical collar is to immobilize the neck and hold it in a gravity-neutral position Tynor Cervical Collar Hard Adjustable is used for supporting, immobilizing or adjusting the neck in the flexion, extension, or hyperextension position. Recommended where a rigid immobilization of the cervical region is required. Anatomical shape. Comfortable edge padding. Adjustable height. Slight weight. Latex free. The soft cervical collar is not designed to completely restrict motion. It depends on providing resistance to movement, which tells the patient to restrict their movements. The soft collar i
Nathan Goodyear

Zoledronic acid in the management of metastatic bone disease - 0 views

  •  
    zometa useful in treatment of metastatic bone disease for purpose of prevention of pathological fractures and treatment of bone pain.
Nathan Goodyear

Evaluation of FLT-PET-CT as an imaging biomarker of proliferation in primary breast can... - 0 views

  • We have demonstrated that the majority of patients have a sizeable reduction in SUVmax from a single cycle of NAC with a mean change of −32.3%
  • This study, however, failed to show any predictive markers of response after one cycle of chemotherapy
  • These data therefore suggest that the main utility of FLT-PET as an imaging biomarker in early breast cancer is pre-chemotherapy, as a marker of proliferation, rather than in predicting pathological response after chemotherapy
  • ...2 more annotations...
  • In terms of the histological proliferation biomarker Ki-67, we have shown a good correlation with FLT-PET pre-chemotherapy. The best predictive marker of response in terms of pCR was baseline Ki-67
  • Our study has shown that baseline Ki-67 and FLT SUVmax is well correlated in keeping with FLT-PETs status as a proliferation biomarker, although Ki-67 had a better predictive ability in terms of pathological outcome
  •  
    PET CT scan shown to be useful as a proliferation biomarker pre-chemo in breast cancer.
Nathan Goodyear

Endothelial cell damage is the central part of COVID-19 and a mouse model induced by in... - 0 views

  •  
    It is concluded that ACE2+ endothelial damage is a central part of SARS-CoV2 pathology and may be induced by the spike protein alone.
Nathan Goodyear

Chemotherapy-Induced Late Transgenerational Effects in Mice - PMC - 0 views

  •  
    Peaks in 4-6th generation
Nathan Goodyear

ScienceDirect.com - The Journal of Nutritional Biochemistry - The role of dietary fatty... - 0 views

  •  
    disordered fat metabolism plays a role in metabolic syndrome
Nathan Goodyear

Testosterone: a vascular hormone in health and disease - 0 views

  • Testosterone has beneficial effects on several cardiovascular risk factors, which include cholesterol, endothelial dysfunction and inflammation
  • In clinical studies, acute and chronic testosterone administration increases coronary artery diameter and flow, improves cardiac ischaemia and symptoms in men with chronic stable angina and reduces peripheral vascular resistance in chronic heart failure.
  • testosterone is an L-calcium channel blocker and induces potassium channel activation in vascular smooth muscle cells
  • ...54 more annotations...
  • Animal studies have consistently demonstrated that testosterone is atheroprotective, whereas testosterone deficiency promotes the early stages of atherogenesis
  • there is no compelling evidence that testosterone replacement to levels within the normal healthy range contributes adversely to the pathogenesis of CVD (Carson & Rosano 2011) or prostate cancer (Morgentaler & Schulman 2009)
  • bidirectional effect between decreased testosterone concentrations and disease pathology exists as concomitant cardiovascular risk factors (including inflammation, obesity and insulin resistance) are known to reduce testosterone levels and that testosterone confers beneficial effects on these cardiovascular risk factors
  • Achieving a normal physiological testosterone concentration through the administration of testosterone replacement therapy (TRT) has been shown to improve risk factors for atherosclerosis including reducing central adiposity and insulin resistance and improving lipid profiles (in particular, lowering cholesterol), clotting and inflammatory profiles and vascular function
  • It is well known that impaired erectile function and CVD are closely related in that ED can be the first clinical manifestation of atherosclerosis often preceding a cardiovascular event by 3–5 years
  • no decrease in the response (i.e. no tachyphylaxis) of testosterone and that patient benefit persists in the long term.
  • free testosterone levels within the physiological range, has been shown to result in a marked increase in both flow- and nitroglycerin-mediated brachial artery vasodilation in men with CAD
  • Clinical studies, however, have revealed either small reductions of 2–3 mm in diastolic pressure or no significant effects when testosterone is replaced within normal physiological limits in humans
  • Endothelium-independent mechanisms of testosterone are considered to occur primarily via the inhibition of voltage-operated Ca2+ channels (VOCCs) and/or activation of K+ channels (KCs) on smooth muscle cells (SMCs)
  • Testosterone shares the same molecular binding site as nifedipine
  • Testosterone increases the expression of endothelial nitric oxide synthase (eNOS) and enhances nitric oxide (NO) production
  • Testosterone also inhibited the Ca2+ influx response to PGF2α
  • one of the major actions of testosterone is on NO and its signalling pathways
  • In addition to direct effects on NOS expression, testosterone may also affect phosphodiesterase type 5 (PDE5 (PDE5A)) gene expression, an enzyme controlling the degradation of cGMP, which acts as a vasodilatory second messenger
  • the significance of the action of testosterone on VSMC apoptosis and proliferation in atherosclerosis is difficult to delineate and may be dependent upon the stage of plaque development
  • Several human studies have shown that carotid IMT (CIMT) and aortic calcification negatively correlate with serum testosterone
  • t long-term testosterone treatment reduced CIMT in men with low testosterone levels and angina
  • neither intracellular nor membrane-associated ARs are required for the rapid vasodilator effect
  • acute responses appear to be AR independent, long-term AR-mediated effects on the vasculature have also been described, primarily in the context of vascular tone regulation via the modulation of gene transcription
  • Testosterone and DHT increased the expression of eNOS in HUVECs
  • oestrogens have been shown to activate eNOS and stimulate NO production in an ERα-dependent manner
  • Several studies, however, have demonstrated that the vasodilatory actions of testosterone are not reduced by aromatase inhibition
  • non-aromatisable DHT elicited similar vasodilation to testosterone treatment in arterial smooth muscle
  • increased endothelial NOS (eNOS) expression and phosphorylation were observed in testosterone- and DHT-treated human umbilical vein endothelial cells
  • Androgen deprivation leads to a reduction in neuronal NOS expression associated with a decrease of intracavernosal pressure in penile arteries during erection, an effect that is promptly reversed by androgen replacement therapy
  • Observational evidence suggests that several pro-inflammatory cytokines (including interleukin 1β (IL1β), IL6, tumour necrosis factor α (TNFα), and highly sensitive CRP) and serum testosterone levels are inversely associated in patients with CAD, T2DM and/or hypogonadism
  • patients with the highest IL1β concentrations had lower endogenous testosterone levels
  • TRT has been reported to significantly reduce TNFα and elevate the circulating anti-inflammatory IL10 in hypogonadal men with CVD
  • testosterone treatment to normalise levels in hypogonadal men with the MetS resulted in a significant reduction in the circulating CRP, IL1β and TNFα, with a trend towards lower IL6 compared with placebo
  • parenteral testosterone undecanoate, CRP decreased significantly in hypogonadal elderly men
  • Higher levels of serum adiponectin have been shown to lower cardiovascular risk
  • Research suggests that the expression of VCAM-1, as induced by pro-inflammatory cytokines such as TNFα or interferon γ (IFNγ (IFNG)) in endothelial cells, can be attenuated by treatment with testosterone
  • Testosterone also inhibits the production of pro-inflammatory cytokines such as IL6, IL1β and TNFα in a range of cell types including human endothelial cells
  • decreased inflammatory response to TNFα and lipopolysaccharide (LPS) in human endothelial cells when treated with DHT
  • The key to unravelling the link between testosterone and its role in atherosclerosis may lay in the understanding of testosterone signalling and the cross-talk between receptors and intracellular events that result in pro- and/or anti-inflammatory actions in athero-sensitive cells.
  • testosterone functions through the AR to modulate adhesion molecule expression
  • pre-treatment with DHT reduced the cytokine-stimulated inflammatory response
  • DHT inhibited NFκB activation
  • DHT could inhibit an LPS-induced upregulation of MCP1
  • Both NFκB and AR act at the transcriptional level and have been experimentally found to be antagonistic to each other
  • As the AR and NFκB are mutual antagonists, their interaction and influence on functions can be bidirectional, with inflammatory agents that activate NFκB interfering with normal androgen signalling as well as the AR interrupting NFκB inflammatory transcription
  • prolonged exposure of vascular cells to the inflammatory activation of NFκB associated with atherosclerosis may reduce or alter any potentially protective effects of testosterone
  • DHT and IFNγ also modulate each other's signalling through interaction at the transcriptional level, suggesting that androgens down-regulate IFN-induced genes
  • (Simoncini et al. 2000a,b). Norata et al. (2010) suggest that part of the testosterone-mediated atheroprotective effects could depend on ER activation mediated by the testosterone/DHT 3β-derivative, 3β-Adiol
  • TNFα-induced induction of ICAM-1, VCAM-1 and E-selectin as well as MCP1 and IL6 was significantly reduced by a pre-incubation with 3β-Adiol in HUVECs
  • 3β-Adiol also reduced LPS-induced gene expression of IL6, TNFα, cyclooxygenase 2 (COX2 (PTGS2)), CD40, CX3CR1, plasminogen activator inhibitor-1, MMP9, resistin, pentraxin-3 and MCP1 in the monocytic cell line U937 (Norata et al. 2010)
  • This study suggests that testosterone metabolites, other than those generated through aromatisation, could exert anti-inflammatory effects that are mediated by ER activation.
  • The authors suggest that DHT differentially effects COX2 levels under physiological and pathophysiological conditions in human coronary artery smooth muscle cells and via AR-dependent and -independent mechanisms influenced by the physiological state of the cell
  • There are, however, a number of systematic meta-analyses of clinical trials of TRT that have not demonstrated an increased risk of adverse cardiovascular events or mortality
  • The TOM trial, which was designed to investigate the effect of TRT on frailty in elderly men, was terminated prematurely as a result of an increased incidence of cardiovascular-related events after 6 months in the treatment arm
  • trials of TRT in men with either chronic stable angina or chronic cardiac failure have also found no increase in either cardiovascular events or mortality in studies up to 12 months
  • Evidence may therefore suggest that low testosterone levels and testosterone levels above the normal range have an adverse effect on CVD, whereas testosterone levels titrated to within the mid- to upper-normal range have at least a neutral effect or, taking into account the knowledge of the beneficial effects of testosterone on a series of cardiovascular risk factors, there may possibly be a cardioprotective action
  • The effect of testosterone on human vascular function is a complex issue and may be dependent upon the underlying androgen and/or disease status.
  • the majority of studies suggest that testosterone may display both acute and chronic vasodilatory effects upon various vascular beds at both physiological and supraphysiological concentrations and via endothelium-dependent and -independent mechanisms
  •  
    Good deep look into the testosterone and CVD link.
Nathan Goodyear

Diagnostic Pathology | Full text | Estrogen receptor beta expression in prostate adenoc... - 0 views

  •  
    ER beta and prostate cancer.  More aggressive prostate cancer is found to be associated with lower ER beta expression in the prostate.  this makes sense, as other studies have shown that ER beta in the prostate can induce apoptosis (cell death), which is a powerful mechanism to regulate uncontrolled growth as found in cancer.
Nathan Goodyear

The therapeutic implications of ketone bodies: the effects of ketone bodies in patholog... - 0 views

  •  
    need to access this article
Nathan Goodyear

The telomerase activator TA-65 elongates short telomeres and increases health span of a... - 0 views

  • studies have demonstrated that the shortest telomeres are causal of reduced cell viability
  • a stable and enforced expression of telomerase leads to an improved health-span, accompanied by an extension of lifespan
  • TA-65 influences the percentage of cellular short telomeres through the activation of telomerase
  • ...17 more annotations...
  • TA-65 administration during 4 months significantly improved the capacity to uptake glucose after a glucose pulse
  • liver protective action of TA-65
  • A disadvantage of mTERT potentiation could be associated to its capacity to favor proliferation of cancerous cells in murine models
  • TA-65 treated mice presented a similar incidence of malignant cancers at time of death, with a tendency to show decreased sarcomas and slightly increased lymphomas
  • We demonstrate here that TA-65 leads to a significant rescue of short telomeres through telomerase activation
  • TA-65 treatment increases proliferation and mobilization potential of mouse keratinocytes in vitro, a situation mimicking telomerase overexpression
  • TAT2, a similar molecule, have beneficial effects in the activation of CD8+ T lymphocytes from HIV-infected patients where they observe an increase of the proliferative potential and enhancement of cytokine/chemokine production
  • TA-65 resulted in a similar rescue of short telomeres in leukocytes post-treatment as observed with humans, most likely through an activation of telomerase
  • we observe that TA-65 lead to 10 fold increase of telomerase RNA levels in the liver of treated mice comparing to the non-treated same-age cohorts
  • TA-65 regulates telomerase at the transcription level, probably through the regulation of the MAPK pathway
  • TA-65 dependent telomerase activation results in a better organ fitness as demonstrated by the improved scores at the glucose tolerance test and insulin levels at fasting
  • TA-65 supplemented mice also present modest enhancement of the subcutaneous and epidermal thickness, as well as higher bone density, representative of an overall fitness status improvemen
  • TA-65 treated mice present higher levels of RBC and hemoglobin comparing to the control cohorts
  • improved health-span of TA-65 treated mice is not accompanied by increased cancer incidence, which may be related to the fact that TERT levels are very modestly increased in all tissues tested except for the liver
  • systemic telomerase overexpression from the germline leads to protection from aging associated pathologies
  • similar situation could be mimicked expressing telomerase late in life in a telomerase deficient background
  • we observed a higher proliferation rate and a partial protection from cell death in some tissues of TA65 treated mice
  •  
    TA-65 shown to increase telomerase activity, and thus telomere length of short telomeres, in mouse study.  
Nathan Goodyear

The Ketogenic Diet and Sport: A Possible Marriage? : Exercise and Sport Sciences Reviews - 0 views

  • It is important to note that, although the blood level of glucose drops, it still remains at a physiological level (23), which is maintained through gluconeogenesis involving glucogenic amino acids and also glycerol released from triglycerides
  • “physiological ketosis” where KB levels may rise to 7 to 8 mmol L-1 (but without any pH change). In “pathological diabetic ketoacidosis,” on the other hand, ketonemia can exceed 20 mmol L-1 and also cause lowering of blood pH
  • in the initial phase of KD, about 16% of glucose comes from glycerol (released from triglyceride hydrolysis) and the bulk (60–65 g) from proteins via gluconeogenesis (proteins may be of either dietary or endogenous origin
  • ...5 more annotations...
  • the protein supply consumed during a KD “preserves,” as demonstrated, lean body mass
  • The importance of glycerol as a glucose source increases progressively during ketosis; in fact, glycerol passes from supplying 16% of total glucose to an average of 60% after many days (>7 d) of complete fasting (from 38% in lean individual to 79% in the obese).
  • The possible reasons for the effectiveness of KD for weight loss may be listed as follows, in order of evidence, strongest first: Figure 3Image Tools 1. Appetite reduction: protein satiety, effects on appetite-related hormones such as ghrelin, and possibly a sort of direct appetite-blocking effect of KB 2. Reduced lipogenesis and increased fat oxidation 3. A reduction in respiratory quotient may indicate a greater metabolic efficiency in fat oxidation 4. A thermic effect of proteins and increased energy usage by gluconeogenesis
  • all data regarding biochemical and molecular mechanisms suggest that it is very difficult to increase muscle mass during a KD; use of which really should be limited to the few days immediately before competition in bodybuilding.
  • a long-term KD can interfere with some muscle hypertrophy mechanisms and this could be counterproductive if the aim of the athlete is to gain muscle mass
  •  
    Great read on the ketogenic  and its application to sports/training...
Nathan Goodyear

Gender and sex hormones in multiple sclerosis pathology and therapy - 0 views

  • It is now well recognized that the disease manifestation is reduced in pregnant women with relapsing-remitting MS
  • This occurs particularly during the third trimester when levels of estrogens (estradiol and estriol) and progesterone (see Table 2) are elevated up to about 20 times
  • This seems well correlated with a decrease in active white matter lesions detected by MRI
  • ...12 more annotations...
  • This clinical improvement is however followed by temporary rebound exacerbations at post-partum, when the hormone levels decline
  • a shift from Th1 to Th2 immune response, expansion of suppressive regulatory T lymphocytes and decrease in the number of circulating CD16+ natural killer (NK)-cells
  • Th1 lymphocytes secrete proinflammatory cytokines (e.g. IL-2, IFNgamma, lymphotoxin) while Th2 cells secrete anti-inflammatory cytokines (e.g. IL-4, IL-5, IL-10), which favor humoral-mediated responses
  • Th2 cytokines are associated with down-regulation of Th1 cytokines and this Th2 shift is believed to provide protection from allograft rejection during pregnancy as well as from Th1-mediated autoimmune disease
  • it is worth noting that the levels of other hormones with anti-inflammatory activity (1,25-dihydroxy-vitamin D3, norepinephrine, cortisol) also increase by 2 to 4 times during late pregnancy
  • 1,25-dihydroxy vitamin D3 induces regulatory T-cell function important for development of self-tolerance
  • breast-feeding does not alter the relapse rate in women with MS
  • Leptin is a pleiotropic hormone produced primarily by adipocytes but also by T lymphocytes and neurons
  • Several lines of evidence indicate that leptin contributes to EAE/MS pathogenesis, influencing its onset and clinical severity, by acting as a proinflammatory cytokine which promotes regulatory T cell (Treg) anergy and hyporesponsiveness, resulting in increased Th1 (TNFalpha, INFgamma) and reduced Th2 (IL-4) cytokine production
  • circulating leptin levels are increased in relapsing-remitting MS patients (men and women analyzed together) while the CD4+CD25+Treg population decreases
  • As the leptin plasma concentrations are proportional to the amount of fat tissue, obese/overweight individuals produce higher levels of leptin
  • Nielsen et al found that estradiol and progesterone exert neuroprotection against glutamate neurotoxicity, while MPA antagonizes the neuroprotective effect of estradiol and exacerbated neuron death induced by glutamate excitotoxicity
  •  
    very good review of the differences in MS and hormones between the sexes.
Nathan Goodyear

Studies on the Progesterone Receptor Content and Steroid Metabolism in Normal and Patho... - 0 views

  •  
    One of the first studies to document progesterone metabolites in breast tissue.
Nathan Goodyear

An endocrine pathway in the prostate, ERβ, AR, 5α-androstane-3β,17β-diol, and... - 0 views

  • Although the prostate is an androgen-dependent tissue, estrogens influence both normal functions and pathological changes in this gland
  • This dual action may be due to the existence of two estrogen receptors, ERα and ERβ
  • ERα and ERβ have similar affinities for estradiol-17β
  • ...6 more annotations...
  • In this study we have shown that regulation of the levels of 3βAdiol by CYP7B1 is a key factor in regulation of prostatic growth
  • We provide evidence that proliferating cells in the prostate epithelium have elevated levels of AR and that AR protein but not mRNA levels are regulated by ERβ and its ligand 3βAdiol in the prostate epithelium.
  • because inhibition of 5α-reductase causes accumulation of testosterone and removal of ERβ action increases the level of AR in the prostate, the overall effect of Finasteride would be to favor proliferation of the prostate epithelium
  • studies show that ERβ tends to be lost in advanced prostate cancer.
  • DHEA is converted in the body to 5-androstene-3β,17β-diol, which is also a ligand for estrogen receptors (25, 39) and a substrate for CYP7B1
  • At the peak of proliferation, the proliferating epithelial cells in the ventral prostate expressed high levels of CYP7B1 but had no detectable ERβ, whereas in nonproliferating cells the level of ERβ was high and that of CYP7B1 was low.
  •  
    3-beta androstanediola, a product of 3alpha-HSD from DHT binds to ER beta and down regulates AR in prostate cancer.  This study proposes that the mechanism is via CYP7B1.  CYP7B1 inactivates 3-beta androstanediol.  Interesting, because 3-beta androstanediol is considered "inactive" when compared to 3-alpha androstanediol and its interaction with ER alpha.  
Nathan Goodyear

Clinical and Pathological Roles of Ro/SSA Autoantibody System - 0 views

  •  
    Clinical use of anti-SSA antibodies.  Most commonly linked with Lupus and Sjogren's syndrome.  
Nathan Goodyear

Nutrition & Metabolism | Full text | Fructose, insulin resistance, and metabolic dyslip... - 0 views

  • For thousands of years humans consumed fructose amounting to 16–20 grams per day
  • daily consumptions amounting to 85–100 grams of fructose per day
  • Of key importance is the ability of fructose to by-pass the main regulatory step of glycolysis, the conversion of glucose-6-phosphate to fructose 1,6-bisphosphate, controlled by phosphofructokinase
  • ...29 more annotations...
  • Thus, while glucose metabolism is negatively regulated by phosphofructokinase, fructose can continuously enter the glycolytic pathway. Therefore, fructose can uncontrollably produce glucose, glycogen, lactate, and pyruvate, providing both the glycerol and acyl portions of acyl-glycerol molecules. These particular substrates, and the resultant excess energy flux due to unregulated fructose metabolism, will promote the over-production of TG (reviewed in [53]).
  • Glycemic excursions and insulin responses were reduced by 66% and 65%, respectively, in the fructose-consuming subjects
  • reduction in circulating leptin both in the short and long-term as well as a 30% reduction in ghrelin (an orexigenic gastroenteric hormone) in the fructose group compared to the glucose group.
  • A prolonged elevation of TG was also seen in the high fructose subjects
  • Both fat and fructose consumption usually results in low leptin concentrations which, in turn, leads to overeating in populations consuming energy from these particular macronutrients
  • Chronic fructose consumption reduces adiponectin responses, contributing to insulin resistance
  • A definite relationship has also been found between metabolic syndrome and hyperhomocysteinemia
  • the liver takes up dietary fructose rapidly where it can be converted to glycerol-3-phosphate. This substrate favours esterification of unbound FFA to form the TG
  • Fructose stimulates TG production, but impairs removal, creating the known dyslipidemic profile
  • the effects of fructose in promoting TG synthesis are independent of insulinemia
  • Although fructose does not appear to acutely increase insulin levels, chronic exposure seems to indirectly cause hyperinsulinemia and obesity through other mechanisms. One proposed mechanism involves GLUT5
  • If FFA are not removed from tissues, as occurs in fructose fed insulin resistant models, there is an increased energy and FFA flux that leads to the increased secretion of TG
  • In these scenarios, where there is excess hepatic fatty acid uptake, synthesis and secretion, 'input' of fats in the liver exceed 'outputs', and hepatic steatosis occurs
  • Carbohydrate induced hypertriglycerolemia results from a combination of both TG overproduction, and inadequate TG clearance
  • fructose-induced metabolic dyslipidemia is usually accompanied by whole body insulin resistance [100] and reduced hepatic insulin sensitivity
  • Excess VLDL secretion has been shown to deliver increased fatty acids and TG to muscle and other tissues, further inducing insulin resistance
  • the metabolic effects of fructose occur through rapid utilization in the liver due to the bypassing of the regulatory phosphofructokinase step in glycolysis. This in turn causes activation of pyruvate dehydrogenase, and subsequent modifications favoring esterification of fatty acids, again leading to increased VLDL secretion
  • High fructose diets can have a hypertriglyceridemic and pro-oxidant effect
  • Oxidative stress has often been implicated in the pathology of insulin resistance induced by fructose feeding
  • Administration of alpha-lipoic acid (LA) has been shown to prevent these changes, and improve insulin sensitivity
  • LA treatment also prevents several deleterious effects of fructose feeding: the increases in cholesterol, TG, activity of lipogenic enzymes, and VLDL secretion
  • Fructose has also been implicated in reducing PPARα levels
  • PPARα is a ligand activated nuclear hormone receptor that is responsible for inducing mitochondrial and peroxisomal β-oxidation
  • decreased PPARα expression can result in reduced oxidation, leading to cellular lipid accumulation
  • fructose diets altered the structure and function of VLDL particles causing and increase in the TG: protein ratio
  • LDL particle size has been found to be inversely related to TG concentration
  • therefore the higher TG results in a smaller, denser, more atherogenic LDL particle, which contributes to the morbidity of the metabolic disorders associated with insulin resistance
  • High fructose, which stimulates VLDL secretion, may initiate the cycle that results in metabolic syndrome long before type 2 diabetes and obesity develop
  • A high flux of fructose to the liver, the main organ capable of metabolizing this simple carbohydrate, disturbs normal hepatic carbohydrate metabolism leading to two major consequences (Figure 2): perturbations in glucose metabolism and glucose uptake pathways, and a significantly enhanced rate of de novo lipogenesis and TG synthesis, driven by the high flux of glycerol and acyl portions of TG molecules coming from fructose catabolism
  •  
    Fructose and metabolic syndrome.  Good discussion of the impact of high fructose intake and metabolic dysfunction.  This study also does a great job of highlighting the historical change of fructose intake.
1 - 20 of 66 Next › Last »
Showing 20 items per page