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Nathan Goodyear

Therapeutic hyperthermia: The old, the new, and the upcoming - Critical Reviews in Onco... - 1 views

  • not well understood, but it is felt to be a combination of both heat-induced necrosis and of protein inactivation (e.g., repair enzymes) as opposed to DNA damage
  • alterations in tumor cytoskeletal and membrane structures, which disrupt cell motility and intracellular signal transduction
  • A common explanation for HT-enhancement of RT and CT involves inhibition of homologous recombination repair of double-strand DNA breaks, preventing cells from repairing sub-lethal damage
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  • it does appear to inhibit rejoining of RT-induced DNA breaks more than is commonly observed after RT alone
  • HT damages cells and enhances RT and CT sensitivity as a function of both temperature and duration of treatment
  • as temperature or duration increase, the rate of cell killing also increases
  • At temperatures above 42 °C, tumor vasculature is damaged, resulting in decreased blood flow
  • Cancer cells are particularly vulnerable to heating; in vivo studies have shown that temperatures in the range of 40–44 °C cause more selective damage to tumor cells
  • cancerous blood vessels are chaotic, leaky, and inefficient
  • selective cytotoxic effect on tumor cells include inhibition of key cancer cell-signaling pathways such as AKT, inducing apoptosis, suppression of cancer stem cell proliferation, and others
  • increase in immunological attacks against tumors after HT, which were believed to be achieved through activation of HSPs and subsequent modulation of the innate and adaptive immune responses against tumor cells
  • HT does lead to activation of the immune system and HSP-induced cell death through modification of the tumor cell surface
  • These HSPs and tumor antigens are taken up by dendritic cells and macrophages and go on to induce specific anti-tumor immunity
  • In vivo studies demonstrate HT-enhancement of NK cell activity, and HT has been shown to increase neutrophilic granulocytes with anti-tumor activity
  • it has become increasingly clear that HT results in immune stimulation, through both direct heat-mediated cell killing as well as innate and adaptive immune system modulation
  • The term hyperthermia is used in this review to refer to heating within the clinically accepted range of 40–45 °C
  • temperatures above 42.5–43 °C the exposure time can be halved with each 1 °C increase while maintaining equivalent cell killing
  • gradual heating at 43 °C for 1 h worked through an apoptotic pathway
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    Comprehensive review of hyperthemic therapy.
Nathan Goodyear

The Risk of Fluoroquinolone-induced Tendinopathy and Tendon Rupture - 0 views

  • Achilles tendinitis or rupture is among the most serious side effects associated with FQ use
  • The large body of data provided by clinical reports, histopathological examination, and experimental studies provides cogent evidence supporting a direct link between FQ use and tendonitis/tendon rupture
  • Risk factors associated with FQ-induced tendon disorders include age greater than 60 years, corticosteroid therapy, renal failure, diabetes mellitus, and a history of musculoskeletal disorders
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  • The average age of FQ-induced tendinopathy is 64 years, with a male-to-female ratio of 2:1, and a 27-percent incidence of bilateral involvement
  • Although more than 95 percent of cases of tendinitis/rupture secondary to FQ involve the Achilles tendon, other reported sites of tendon involvement include the quadriceps, peroneus brevis, and rotator cuff
  • FQs demonstrate a 3.8-fold greater risk for development of Achilles tendinitis/rupture
  • a large population-based case control analysis, patients treated with FQs exhibited a substantially increased risk of developing tendon disorders overall (1.7-fold), tendon rupture (1.3-fold), and ATR (4.1-fold)
  • patients taking FQs with concurrent exposure to corticosteroids were found to experience a compounding effect on the risk of tendon rupture, specifically a 46-fold greater predisposition
  • Some authors have recommended that patients with a history of Achilles tendinitis and advanced age should not be prescribed FQ antibiotics
  • Approximately 50 percent of patients will recover within 30 days, with 25 percent of patients having symptoms persistent for longer than two months
  • The mean latency period between the start of FQ treatment and occurrence of tendinopathy has been reported to be a few hours to months, with a median onset of 6 days
  • The exact pathophysiology of FQ-induced tendinopathy remains elusive
  • it is possible that FQs have a direct cytotoxic effect on enzymes found in mammalian musculoskeletal tissue
  • It has been theorized that FQs disproportionately affect human tendons that have a limited capacity for repair, such as in older patients or structural compromise (i.e., pre-existing tendinopathy or trauma)
  • histopathological findings are similar to those observed in overuse conditions in athletes
  • Treatment with a FQ should be discontinued and physical therapy initiated
  • treatment should include rest and decreasing the physical load on the tendon.
  • Approximately 85 percent of patients present in less than one month
  • Because rupture can occur even late in the course of treatment or after discontinuation of FQ use, patients receiving a FQ should be counseled to seek medical attention immediately if symptoms, such as redness, pain, swelling, and stiffness, develop
  • FQs should be used cautiously in patients with risk factors associated with tendinitis, such as advanced age, history of tendon rupture, corticosteroid use, and/or acute or chronic renal dysfunction
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    Great review of the link between flouroquinolones and Tendinitis and Tendon rupture.  Yes, there is a direct link.
Nathan Goodyear

Histamine and histamine intolerance - 0 views

  • Histamine intolerance can develop through both increased availability of histamine and impaired histamine degradation
  • increased availability may be an endogenous histamine overproduction caused by allergies, mastocytosis, bacterias, gastrointestinal bleeding, or increased exogenous ingestion of histidine or histamine by food or alcohol
  • Other biogenic amines, such as putrescine, may also be involved in displacing histamine from its mucosal mucine linkage, which results in an increase of free absorbable histamine in circulation
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  • the main cause of histamine intolerance is an impaired enzymatic histamine degradation caused by genetic or acquired impairment of the enzymatic function of DAO or HNMT
  • The main enzyme for metabolism of ingested histamine is diamine oxidase (DAO)
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    good discussion of histamine and histamine intolerance.  All centers around diamine oxidase function (DAO).
Nathan Goodyear

A Six Months Exercise Intervention Influences the Genome-wide DNA Methylation Pattern i... - 0 views

  • In skeletal muscle, HDAC4 has been found to be exported from the nucleus during exercise, suggesting that removal of the transcriptional repressive function could be a mechanism for exercise adaptation [50]. For HDAC4, we observed increased levels of DNA methylation and a simultaneous decrease in mRNA expression in adipose tissue in response to the exercise intervention. Additionally, the functional experiments in cultured adipocytes suggested increased lipogenesis when Hdac4 expression was reduced
  • NCOR2 also exhibited increased levels of DNA methylation and a simultaneous decrease in mRNA expression in adipose tissue in response to the exercise intervention, and furthermore we observed increased lipogenesis when Ncor2 expression was down regulated in the 3T3-L1 cell line. NCOR2 is a nuclear co-repressor, involved in the regulation of genes important for adipogenesis and lipid metabolism, and with the ability to recruit different histone deacetylase enzymes, including HDAC4
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    Study finds 6 month exercise program in men induced epigenetic change via DNA methylation of CPG islands in adipose cells effecting metabolism and altering obesity and type II diabetes risk.  The study looked at 2 genes: HDAC4 and NCOR2 and found that exercise decreased expression via methylation altering adipogenesis and lipid metabolism.
Nathan Goodyear

Effects of Melatonin and Its Analogues on Pancreatic Inflammation, Enzyme Secretion, an... - 0 views

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    Melatonin metabolites involved in the cancer process. The Indoleamine dioxygenase pathway is the mechanism.
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