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wheelchairindia9

Tynor Hot and Cold Pack - 0 views

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    Tynor Hot and Cold Pack is a convenient device to provide hot fomentation or cold compress. Hot fomentation of the injured or inflamed area enhances the threshold of pain and thus reduces the perception of pain. It has a synergistic effect along with pain relieving drugs. Raising temperature of the injured tissue also enhances the blood profusion and the healing process. Hot fomentation has a relaxing effect. Cold compress helps in reduction of inflammation in injuries, protects by slowing the metabolic rate around the tissue, reduce oedema and bleeding. Cold compress helps in immediately lowering fever, in very high fever conditions. It can be used after an acute injury or surgical procedure. No heat or cryo burns. Requires no holding. Reusable. Easy application. Appealing aesthetics. Tynor Hot and Cold Pack Features Multi functionality Reduce swelling and odema at the site of injury. Muscles spasm and pain. Headache and minor injuries. Versatile design Can be used as either cold or hot pack. Reusable in either hot & cold condition. Temperature range - Can be used from 0 Cº to 75Cº. Longer temperature retention time. Fabric cover ensures no cryo burns or hot skin burns. Physical features Non-toxic, and biodegradable. Gel remains soft and flexible upto 0 degree. Durable, and puncture resistant. Soft, "frost free" PVC cover. Flexible conforms to the body contours. Easy to clean and maintain. Excellent workmanship. Good aesthetics. Elastic belt Holds the pack against the body, No need to hold by hand. Enhances convenience. Tynor Hot and Cold Pack Measurements
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.
wheelchairindia9

Abdominal Support Belt - 0 views

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    Tynor Hot and Cold Pack is a convenient device to provide hot fomentation or cold compress. Tynor Hot and Cold Pack is of multipurpose advantage. It is a convenient and effective approach for both hot as well as a cold therapy. Hot pack can be used for body ache, joint pain, etc., whereas a cold pack can be used for fever, sprains, fever, bleeding, etc. It is easy to use and maintains the temperature for a long period of time. It is available in 11.22 x 7.67 inch universal sizes. Hot fomentation of the injured or inflamed area enhances the threshold of pain and thus reduces the perception of pain. It has a synergistic effect along with pain relieving drugs. Raising temperature of the injured tissue also enhances the blood profusion and the healing process. Hot fomentation has a relaxing effect. Cold compress helps in reduction of inflammation in injuries, protects by slowing the metabolic rate around the tissue, reduce oedema and bleeding. Cold compress helps in immediately lowering fever, in very high fever conditions. It can be used after an acute injury or surgical procedure. No heat or cryo burns. Requires no holding. Reusable. Easy application. Appealing aesthetics. Tynor Hot and Cold Pack Features Multi functionality Reduce swelling and odema at the site of injury. Muscles spasm and pain. Headache and minor injuries. Versatile design Can be used as either cold or hot pack. Reusable in either hot & cold condition. Temperature range - Can be used from 0 Cº to 75Cº. Longer temperature retention time. Fabric cover ensures no cryo burns or hot skin burns. Physical features Non-toxic, and biodegradable. Gel remains soft and flexible upto 0 degree. Durable, and puncture resistant. Soft, "frost free" PVC cover. Flexible conforms to the body contours. Easy to clean and maintain. Excellent workmanship. Good aesthetics. Elastic belt Holds the pack against the body, No need to hold by hand. Enhances convenience. Tynor
Nathan Goodyear

Core body temperature in obesity - 0 views

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    Core temperature not statistically different betweeen obese and non-obese individuals
Nathan Goodyear

Hyperthermia as an immunotherapy strategy for cancer - 1 views

  • the notion of treating human cancers with heat dates back to the writings of Hippocrates
  • enhance the efficiency of standard cancer therapies, such as chemotherapy and radiation treatment
  • After antigen uptake at tumor sites, APCs have the ability to create a robust response by entering lymphoid compartments and programming lymphocytes
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  • Hyperthermia differs fundamentally from fever in that it elevates the core body temperature without changing the physiological set point
  • hyperthermia is induced by increasing the heat load and/or inactivating heat dissipation
  • mor cells [2]. Although significant cell killing could be achieved by heating cells or tissues to temperatures > 42°C for 1 or more hours, the application, measurement and consistency of this temperature range within the setting of cancer clinical trials
  • mild temperature hyperthermia (ie, within the fever-range, 39–41°C)
    • Nathan Goodyear
       
      101.2 to 105.8
  • moderate hyperthermia (41°C)
    • Nathan Goodyear
       
      105.8 F
  • Hsps are a family of stress-induced proteins
  • they are key regulators of cellular protein activity, turnover and trafficking
  • Hsps ensure appropriate post-translational protein folding, and are able to refold denatured proteins, or mark irreversibly damaged proteins for destruction
  • the ability of fever-range hyperthermia to induce reactive immunity against tumor antigens through DCs and NK-cells is likely mediated by Hsps
  • thermotolerance
  • Hsps support the malignant phenotype of cancer cells by not only affecting the cells’ survival, but also participating in angiogenesis, invasion, metastasis and immortalization mechanisms
  • Hsps released from stressed or dying cells activate dendritic cells (DCs), transforming them into mature APCs
  • In theory, fever-range hyperthermia may take advantage of tumor cell Hsps by inducing their release from tumor cells and augmenting DC priming against tumor antigens
  • In several models of hyperthermia, heat-treated tumors exhibited improved DC priming and generation of systemic immunity to tumor cell
  • hyperthermia alone can enhance antigen display by tumor cells, thus rendering them even more susceptible to programmed immune clearance
  • Fever-range hyperthermia may also induce Hsps
  • Hsps may exert an adjuvant effect by bolstering MHC class II and co-stimulatory molecule expression by DCs
  • thermal ablation of liver tumors in particular has demonstrated an ability to potentiate immune responses [57, 58] and elicit robust T-cell infiltrates at ablation sites
  • specific Hsp, Hsp70, directly inhibits apoptosis pathways in cancer cells, as demonstrated in human pancreatic, prostate and gastric cancer cells
  • Cross-priming is the ability of extracellular Hsps complexed to tumor peptides to be internalized and presented in the context of MHC class I molecules on APCs, thus allowing potent priming of CTLs against tumor antigens
  • It has been reported that Hsps are generated from necrotic tumor cell lysates, but not from tumor cells undergoing apoptosis
  • tumor cells exposed to hyperthermia in the heat shock range (42°C for 4h) prior to lysing, DC activation and cross-priming were significantly enhanced with the application of heat
  • Due to the ability of Hsps to activate DCs directly by chaperoning tumor antigens upon their release [28], it is possible that both local and regional immune stimulation can be achieved with hyperthermia.
  • support the use of hyperthermia as an inducer of Hsps to serve as ‘danger signals’, activating antitumor immune responses
  • whole-body hyperthermia not only augments immune responses, but also stimulates the migration of skin-derived DCs to draining lymph nodes
    • Nathan Goodyear
       
      This allows for the activation of lymphocytes by the activated dendritic cells.
  • suggest a valuable role of hyperthermia in DC cancer vaccine strategies
  • In mice treated with fever-range whole-body hyperthermia, tumor growth was significantly inhibited and NK-cell infiltration increased
    • Nathan Goodyear
       
      Hyperthermia increased NK cell activation, proliferation, and infiltration, which equals increased cytotoxicity.
  • exposure to fever-range hyperthermia resulted in improved endogenous NK-cell cytotoxicity to several cancer types
  • improved activation and function of DCs and NK cells following hyperthermia
  • Hyperthermia increases the expression ICAM-1 a key adhesion molecule,
  • The combined effects of hyperthermia on lymphoid tissue endothelium and lymphocytes can promote immune surveillance and increase the probability of naive lymphocytes leaving the circulation and encountering their cognate antigen displayed by DCs in lymphoid organs.
  • In independent clinical studies, whole-body hyperthermia resulted in a transient decrease in circulating lymphocytes in patients with advanced cancer [12, 94, 99, 100], a finding which mirrored observations in animal models in which lymphocyte entry into lymph noeds was increased following hyperthermia treatment [93]. Enhanced recruitment of lymphocytes to lymphoid tissues may be exploited in the treatment of malignancies.
  • The initial tumor antigen presentation and initiation of clonal expansion of CTLs transpires in the lymph nodes and cannot take place outside this specialized compartment
  • the ability of DCs present in the lymph nodes to stimulate an anti-tumor immune response is critical
  • hyperthermia has been shown to improve immune surveillance by T-cell
  • and to increase DC trafficking to lymph nodes
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    Great review of hyperthermia.
Nathan Goodyear

Temperature-dependent and time-dependent effects of hyperthermia mediated by dextran-co... - 0 views

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    effect of time and temperature on the viability of melanoma cell lines and expression of HSP 70 & 90 after brief exposure to hyperthermia. While hyperthermia has multiple mechanisms of action, this paper elucidates two essential benefits of high-dose hyperthermia. First, the study illustrates why high-dose hyperthermia treatments (45°C - 47°C) are so much more effective than the low-dose hyperthermia (39°C - 43°C) produced by commercially available heating devices.
Nathan Goodyear

Liquid Chromatography-tandem Mass Spectrometry (LC-MS/MS) Assay for Simultaneous Measur... - 0 views

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    MS-LS show to be highly sensitive in the dual identification of testosterone and cortisol in saliva. These hormones were found to be stable up to 28 days at room temperature. This disproves the argument that saliva, as a test medium, has a very short shelf life.
wheelchairindia9

Best Wheelchair For Heavy Person - 0 views

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    People who are very large or heavy may have difficulty using regular chairs. In some cases, they are simply too wide to comfortably fit in an average-sized chair, and in other cases their weight may damage or break the chair entirely. This is not only humiliating to the person who sits in the chair, but could result in injury if the chair collapses. To avoid such an unfortunate occurrence as well as potential litigation, it is important to purchase heavy duty chairs that can accommodate larger family members, employees, and customers. Heavy duty wheelchairs can also be made for specific purposes. An off-road wheelchair, for example, is a heavy duty wheelchair designed for individuals who intend on spending a lot of time on rugged terrain. The most common type of heavy duty wheelchair is a bariatric wheelchair, which is designed to allow larger individuals adequate mobility. For this matter, heavy duty wheelchairs typically have larger seats than conventional wheelchairs. The frames of these wheelchairs can be made from several different reinforced metals, although a titanium wheelchair is often the most popular choice. The wheels themselves are made of thicker rubber than normal, preventing any possible failure due to the greater amount of weight supported. Most makes of heavy duty wheelchairs fold like regular wheelchairs, making storage relatively easy despite the wheelchair's increased size. For the user's convenience, a heavy duty wheelchair can either be manually-operated or motorized, each with its own pros and cons. A manual Heavy Duty Wheelchair gives full control of motion to the user, but the added weight from the reinforcements makes pushing or propelling the wheelchair much harder than normal. A motorized heavy duty wheelchair offers a solution to this dilemma, but is often more expensive and harder to maintain than a manual wheelchair. Some designs offer a combination of both, with a small motor assisting those pushing the wheelchair. The proper c
Nathan Goodyear

Intravenous Fluid Use in Athletes - 0 views

  • Treatment of exercise-associated hyponatremia with hypertonic IV infusion to correct plasma sodium levels is also a standard and accepted use of IV fluid infusions
  • athletes who present for medical care with hypernatremia who cannot tolerate oral fluids can benefit from IV fluids
  • Vaporization of sweat accounts for 80% of heat loss in hot, dry atmospheric conditions. This mechanism of water loss is the major contributor for exercise-associated dehydration
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  • The rate of water loss can be quantified through measurement of sweat rate
  • Pre- and postexercise body weight measurements are the most common means to estimate overall water loss but are condition specific
  • It appears that 1% to 2% body weight loss is well tolerated by the exercising athlete
  • Dehydration, defined as greater than 2% loss of body weight, can negatively affect performance
  • In highly trained endurance athletes, plasma volume and sodium serum concentration were preserved despite a 5% body weight loss
  • In Ironman triathletes, dehydration to 5% body weight loss did not correlate with occurrence of medical complications
  • hydration should begin hours prior to exercise, especially if known deficits are present, and fluids should be consumed at a slow, steady rate, with 5 to 7 mL/kg taken 4 hours prior to exercise
  • Sodium concentration did not produce significant changes in the rate of absorption but was primarily dependent on carbohydrate concentration
  • Replacing 150% of body weight loss over 60 minutes has been tolerated without complications
  • IV treatment of severe dehydration (>7% body weight loss), exertional heat illness, nausea, emesis, or diarrhea, and in those who cannot ingest oral fluids for other reasons, is clinically indicated
  • A recent survey of the National Football League teams revealed that 75% (24 of 32) of the teams utilized IV infusion of fluids for prehydration in at least some otherwise healthy individuals
  • In the National Football League, an average of 1.5 L of normal saline was administered approximately 2.5 hours prior to competition
  • after 2 hours of exercise, the rectal temperature was 0.6° higher in the group not receiving IV infusion. Also, stroke volume and cardiac output were 11% to 16% lower in the control group versus the IV infusion group.
  • Recent evidence suggests the etiology of EAMC is related to muscle fatigue and neuronal excitability
  • no correlation between hydration status or electrolyte concentrations with EAMC
  • there may be a subset of muscle cramping that is associated with a loss of both body fluid and sodium
  • Glycerol is the primary agent for oral hyperhydration
  • elevation of plasma volume by 200 to 300 mL via dextran infusion resulted in 15% increase in stroke volume, 4% increase in VO2 max, and an increase in the exercise time to fatigue
  • Neither the tonicity nor mode of hydration resulted in improved speed of rehydration, greater fluid retention, or improved performance
  • There are beneficial anecdotal reports of EAMC treatment in elite and professional-level athletes with IV hydration during the course of an event
  • Plasma volume was better restored during rehydration with IV fluids at preexercise and 5 minutes of exercise. At 15 minutes, there was no difference between IV and oral rehydration
  • More rapid restoration of plasma volume was accomplished in the IV treatment group with no advantages over oral rehydration in physiological strain, heat tolerance, ratings of perceived effort, or thermal sensations
  • No difference was found in exercise time to exhaustion. IV and oral rehydration methods were equally effective. Heart rates were statistically higher in the oral rehydration group through 75 minutes of exercise, and there were higher increases in norepinephrine plasma concentrations
  • No significant differences between the groups were found for time to recovery, number of days with pain, number of days with stiffness, sleep disturbance, fatigue, rectal temperature, and loss of appetite
  • The current data suggest that IV rehydration is faster than oral
  • There may be physiological benefits of decreased heart rate and norepinephrine in athletes rehydrated via IV route
  • Postexercise blood 1 hour and 24 hours showed no differences in circulating myoglobin or creatine kinase
  • The use of IV fluid may be beneficial for a subset of fluid sensitive athletes
  • this should be reserved for high-level athletes with strong histories of symptoms in well-monitored settings.
  • Volume expanders may also be beneficial for some athletes
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    to be read
Nathan Goodyear

Ifosfamide plus etoposide combined with regional hyperthermia in patients with locally ... - 0 views

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    Hyperthermic therapy augments chemotherapy for some with advanced sarcomas.  Systemic temperature at 37.4 C in this study.
Nathan Goodyear

Effect of hyperthermia on the functional activity of cytotoxic T-lymphocytes - PubMed - 0 views

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    Temperature is key to CTL activation versus inactivation.
Nathan Goodyear

Thermal regulation of dendritic cell activation and migration from skin explants - PubMed - 0 views

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    Low temperature hyperthermia, to 40 C, augments dendritic activation and circulation.
Nathan Goodyear

Effects of hyperthermia on normal and tumor microenvironment. | Radiology - 0 views

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    The effect of HT in the TME is dictated but the temperature.
Nathan Goodyear

Effects of hyperthermia on normal and tumor microenvironment. | Radiology - 0 views

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    Only abstract here, but temperature of hyperthermia dictates effects. < 41 C increase in blood flow and O2; > 41 C collapse in blood flow.
umar111

Computer Science: Computer hardware - 0 views

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    Computer Science Tuesday, April 25, 2023 Computer hardware Computer hardware is the physical components that make up a computer system. It includes everything from the central processing unit (CPU) to the monitor, keyboard, and mouse. Understanding the different types of hardware and how they work together is essential for anyone who works with computers. In this article, we will explore the various components of computer hardware, including internal and external components, and the peripherals that connect to them. We will also discuss the importance of hardware maintenance, the latest advancements in computer technology, and factors to consider when choosing the right hardware for your needs. Whether you are a computer technician, a gamer, or simply someone who uses a computer for everyday tasks, this article will help you better understand the world of computer hardware. Introduction to Computer Hardware Computer hardware refers to the physical components that make up a computer system. It includes everything from the processor and memory to input/output devices such as the keyboard and monitor. In this article, we will explore the different types of computer hardware and their functions. What is Computer Hardware Computer hardware refers to the physical components of a computer system. It includes all the components that can be touched, seen, and used to interact with a computer, such as the monitor, keyboard, and mouse. Hardware is different from computer software, which refers to the programs and applications that run on a computer system. History of Computer Hardware The history of computer hardware dates back to the 1820s when Charles Babbage, an English mathematician, and inventor, designed the first analytical engine, which was considered to be the first mechanical computer. With time, more complex electronic computers were developed, including the first Intel microprocessor in 1971. Since then, computer hardware has continued to evolve, becoming
fitspresso

https://www.fitspresso-co.com/ - 0 views

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    FitSpresso™ | Official Site fitspresso-co.com FitSpresso Only $39/Bottle Limited Time Offer! FitSpresso Special Deal + Special 51% Discount Save $660 + 180 Days Money Back Guarantee FitSpresso Herpesyl Five Star A dietary product formulated to assist users in reducing weight can increase other advantages that can support overall health. This product can assist users in getting closer to the desirable body weight. Regular Price: 149/per bottle Only for: $39/per bottle Buy Now What IsFitSpresso? FitSpresso is promoted as a natural supplement that comes in the form of diet pills, and it can aid in rapid and efficient weight loss, similar to many other supplements. The term "natural supplements refers to a nutritional supplement that is made entirely of natural, chemical-free materials. You can utilize these organic ingredients to aid in natural weight loss. It can speed up your body's metabolism and assist with other crucial processes. All parts of our bodies are impacted by weight increase, and not only do we need to deal with the increased weight, but we also need to deal with the numerous problems and illnesses that come along with it. This refers to the risk of developing chronic cardiac conditions, low blood pressure, and, in some circumstances, problems with blood sugar. However, FitSpresso even with its bright and bold claims, can help you efficiently manage your weight and completely avoid these extra uncomfortable problems. FitSpresso is a supplement that comes in the form of a pill, which makes it tasty, simple to swallow, and handy. According to the manufacturer, these diet tablets are GMO-free and toxic-free, making them edible. This is why we have things such as weight loss supplements. Thanks to modern advancements, we can just take a dietary supplement pill to bring about significant weight loss in a completely healthy and natural manner. Not only this, but dietary supplements can also support healthy blood sugar levels and help with
Nathan Goodyear

Progesterone metabolites in breast cancer - 1 views

  • P metabolites produced within breast tissues might be independently active hormones functioning as cancer-promoting or -inhibiting regulatory agents
  • these P metabolites function as independent pro-or anti-cancer autocrine/paracrine hormones that regulate cell proliferation, adhesion, apoptosis and cytoskeletal, and other cell status molecules via novel receptors located in the cell membrane and intrinsically linked to cell signaling pathways
  • only a fraction of all breast cancer patients respond to this estrogen-based therapy and the response is only temporary
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  • P serves as the precursor for the major steroid hormones (androgens, estrogens, corticosteroids) produced by the gonadal and adrenal cortical tissues.
  • 5α-pregnane, 5β-pregnane, and 4-pregnene metabolites of P
  • These P-metabolizing enzymes included 5α-reductase, 5β-reductase, 3α-hydroxysteroid oxido-reductase (3α-HSO), 3β-HSO, 20α-HSO, 20β-HSO, 6α(β)-, 11β-, 17-, and 21-hydroxylase, and C17–20-lyase
  • Reduction of P to 5α-pregnanes is catalyzed by 5α-reductase and the direct 5α-reduced metabolite of P is 5α-pregnane-3,20-dione (5αP). The 5α-reductase reaction is irreversible
  • The two 4-pregnenes resulting from direct P conversion are 4-pregnen-3α-ol-20-one (3αHP) and 4-pregnen-20α-ol-3-one (20αHP), catalyzed by the actions of 3α-HSO and 20α-HSO respectively
  • the P-metabolizing enzyme activities identified in human breast tissues and cell lines were: 5α-reductase, 3α-HSO, 3β-HSO, 20α-HSO, and 6α-hydroxylase
  • In normal breast tissue, conversion to 4-pregnenes greatly exceeded the conversion to 5α-pregnanes, whereas in tumorous tissue, conversion to 5α-pregnanes greatly exceeded that to 4-pregnenes
  • The results indicated that P 5α-reductase activity is significantly higher, whereas P 3α-HSO and 20α-HSO activities are significantly lower in tumor than in normal tissues
  • he results showed that production of 5α-pregnanes was higher and that of 4-pregnenes was lower in tumorigenic (e.g. MCF-7) than in nontumorigenic (e.g. MCF-10A) cells (Fig. 3c⇑), while differences in ER/P status did not appear to play a role
  • The 5α-pregnane-to-4-pregnene ratios were 7- to 20-fold higher in the tumorigenic than in the nontumorigenic cell lines
  • altered direction in P metabolism, and hence in metabolite ratios, was due to significantly elevated 5α-reductase and depressed 3α- and 20α-HSO activities in breast tumor tissues and tumorigenic cells. It appeared, therefore, that changes in P-metabolizing enzyme activities might be related to the shift toward mammary cell tumorigenicity and neoplasia
  • In vivo, changes in enzyme activity can result from changes in levels of the enzyme due to changes in expression of the mRNA coding for the enzyme, or from changes in the milieu in which the enzyme operates (such as temperature and pH, and concentrations of cofactors, substrates, products, competitors, ions, phospholipids, and other molecules)
  • Overall, the enzyme activity and expression studies strongly suggest that 5α-reductase stimulation and 3α- and 20α-HSO suppression are associated with the transition from normalcy to cancer of the breast
  • The level of expression of 5α-reductase is up-regulated by estradiol and P in the uterus (Minjarez et al. 2001) and by 5α-dihydrotestosterone (DHT) in the prostate
  • 3αHP inhibited whereas 5αP-stimulated proliferation
  • Stimulation in cell numbers was also observed when cells were treated with other 5α-pregnanes, such as 5α-pregnan-3α-ol-20-one, 5α-pregnan-20α-ol-3-one, and 5α-pregnane-3α,20α-diol, whereas other 4-pregnenes such as 20α-HP and 4-pregnene-3α,20α-diol resulted in suppression of cell proliferation
  • Stimulation of cell proliferation with 5αP and inhibition with 3αHP were also observed in all other breast cell lines examined, whether ER/P-negative (MCF-10A, MDA-MB-231) or ER/P-positive (T47D, ZR-75-1) and whether requiring estrogen for tumorigenicity (MCF-7, T47D) or not (MDA-MB-231), or whether they are nontumorigenic (
  • αHP resulted in significant increases in apoptosis and decreases in mitosis, leading to significant decreases in total cell numbers. In contrast, treatment with 5αP resulted in decreases in apoptosis and increases in mitosis.
  • The opposing actions of 5αP and 3αHP on both cell anchorage and proliferation strengthen the hypothesis that the direction of P metabolism in vivo toward higher 5α-pregnane and lower 4-pregnene concentrations could promote breast neoplasia and lead to malignancy.
  • he effects on proliferation and adhesion were not due to P, but due to the 5α-reduced metabolites
  • The studies showed that binding of 5αP or 3αHP occurs in the plasma membrane fractions, but not in the nuclear or cytosolic compartments
  • separate high-specificity, high-affinity, low- capacity receptors for 5αP and 3αHP that are distinct from each other and from the well-studied nuclear/cytosolic P, estrogen, and androgen and corticosteroid receptors
  • The studies thus provided the first demonstration of the existence of specific P metabolite receptors
  • the receptor results suggest that the putative tumorigenic actions of 5αP may be significantly augmented by the estradiol-induced increases in 5αP binding and decreases in 3αHP binding.
  • Estradiol and 5αP resulted in significant dose-dependent increases, whereas 3αHP and 20αHP each resulted in dose-dependent decreases in total ER
  • In combination, estradiol + 5αP or 3αHP + 20αHP resulted in additive increases or decreases respectively in ER numbers.
  • The data suggest that the action of 5αP on breast cancer cells involves modulation of the MAPK signaling pathway
  • current evidence does not appear to support the notion that increased 5α-reductase activity/ expression might significantly alter androgen influences on breast tumor growth.
  • both testosterone and DHT inhibit cell growth more or less to the same extent
  • Note that 5α-reductase reaction is not reversible
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    Fantastic read on the effects of progesterone metabolism on tumor and cancer growth.  Tumorigenesis is not just about the hormone, hormone balance, but about the metabolism of hormones.  This is why premarin is so carcinogenic: it is primarily metabolized by the 4-OH estrone pathway.
Amelie warner

Bamboo Tea - 0 views

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    This tea is prudently handpicked and selected in the end of every spring. Tea masters watchfully select its weather temperature, moist, timing... #haocha http://bit.ly/1dLmtd4
Nathan Goodyear

Calculation of free and bound fractions of testosterone and estradiol-17 beta to human ... - 0 views

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    Two percent of Testosterone is free in study of 11 normal men.  53-55% bound to albumin and 43-45% bound to SHBG.
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