Abstract：
:Epoxides as reactive intermediates of estrogen metabolism have been considered to be potential precursors of the 2- and 4-hydroxy, catechol estrogens and even to be mutagenic/carcinogenic agents themselves. The labile nature of the intermediates has made proof of their existence difficult in natural biological conditions. In our studies on estrogen metabolism in vitro, in various tissues from several laboratory and domestic species, there was chromatographic evidence of formation of a stable estrogen metabolite that could be seen after incubation with radiolabeled estrone, but not with unlabeled substrate. Investigation with acid treatment of the metabolite yielded material detected as 6-hydroxy-estrone-suggesting the presence of an additional oxygen atom in the molecule. An identification of the "unknown compound" has not yet been made but, with this evidence, the properties revealed so far can best be met by assuming the presence of 5,6-epoxy-estrone. The recent favorable reports on the role of 5α,6α-epoxy-cholesterol in breast cancer has led to the hypothesis that the formation of a similar, stable epoxide of an estrogen could potentially be a compound of interest. If a metabolic pathway from estrone to 6-hydroxy-estrone through a stable epoxide has indeed been observed, it would suggest that identifying and screening for the enzymes responsible for its production, as opposed to those generating the catecholestrogens, could provide valuable information in relation to breast cancer. The balance in production of estrogen epoxides could be a key factor in determining normal health or risk of tumor development.
journal_name
Med Hypothesesjournal_title
Medical hypothesesauthors
Raeside JIdoi
10.1016/j.mehy.2016.04.012subject
Has Abstractpub_date
2016-06-01 00:00:00pages
37-41eissn
0306-9877issn
1532-2777pii
S0306-9877(16)30025-1journal_volume
91pub_type
杂志文章abstract：:The polyol pathway consists of two enzymes aldose reductase (AR) and sorbitol dehydrogenase (SDH); the former is the first enzyme in the polyol pathway, that catalyzes the reduction of glucose to sorbitol, the latter is the second one, that converts sorbitol to fructose using by NAD(+) as a cofactor. We along with oth...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/s0306-9877(03)00013-6
更新日期：2003-04-01 00:00:00
abstract：:In a recent paper it was argued that all stem cells are small motile cells, the haemopoietic stem cell being no exception. Although haemopoietic stem cells arise and mature in an extravascular milieu, they are present in small numbers in the peripheral circulation, where they have a lymphocyte-like appearance, and in ...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/0306-9877(94)90144-9
更新日期：1994-09-01 00:00:00
abstract：:A neural network approach to modeling the development of personality traits through social learning is presented. From the more general model the special case of a network mapping four situation dimensions (input neurons) into seven dimensional personality traits (output neurons) is described. This network is allowed ...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/0306-9877(93)90057-w
更新日期：1993-08-01 00:00:00
abstract：:Although peripartum cardiomyopathy (PPCM) is a rare disease, it has very serious consequences for both mother and child. No single cause has been held responsible for the pathogenesis. Recent studies have indicated that increased proteolytic cathepsin D activity in cardiomyocytes results in16kDa prolactin fragments wi...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2009.08.029
更新日期：2010-02-01 00:00:00
abstract：:The levator ani muscles in women are overloaded by constant supporting abdominal contents, and counteracting rises of abdominal pressure at the level of the urethra. The excessive load leads to a decrease in their type II fibers. This results in stress urinary incontinence due to loss of the fibers responsible for add...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/0306-9877(93)90225-f
更新日期：1993-06-01 00:00:00
abstract：:The "small-for-size" syndrome and "post-hepatectomy liver failure" refers to the development of liver failure (hyperbilirubinemia, coagulopathy, encephalopathy and refractory ascites) resulting from the reduction of liver mass beyond a certain threshold. This complication is associated with a high mortality and is a m...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2013.01.028
更新日期：2013-05-01 00:00:00
abstract：:One area of relative agreement in schizophrenic research is that there is grey matter volume deficit in various cortical areas associated with this illness. One theory attempting to explain this involves an exaggerated action of the normal CNS pruning process. Various aspects of this process were discussed along with ...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2011.03.038
更新日期：2011-07-01 00:00:00
abstract：:The AIDS dementia complex and peripheral neuropathy in AIDS are considered to be direct or indirect manifestations of HIV infection, yet the pathogenesis in unclear. There are parallels between AIDS and Tangier disease clinically and histopathologically and in lipid metabolism. The neurological disorders in AIDS may b...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/0306-9877(90)90085-s
更新日期：1990-09-01 00:00:00
abstract：:Pulmonary hypertension (PH) is defined as elevated mean pulmonary artery pressure secondary to e.g. congenital heart disease and chronic obstructive pulmonary disease. It elevates right ventricular afterload that eventually leads to cor pulmonale and right heart failure. Experimental research has shown that cardioprot...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2020.109572
更新日期：2020-04-01 00:00:00
abstract：:The exact contribution of the sirtuin family of NAD+-dependent histone deacetylases to longevity in metazoans is, at present, not completely understood but nonetheless regarded as significant. Despite the rapidly accreting evidence solidifying the role of NAD+-dependent histone deacetylase activity in longevity-promot...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2005.08.032
更新日期：2006-01-01 00:00:00
abstract：:Some genes such as those for histones and RNAs are conserved unchanged through much of evolution and have numerous tandem repeat copies in the genome. It is proposed that as yet undetected 'polystrand' enzymes use such multiple copies as a means of conserving their sequence by comparing the copies and eliminating erro...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/0306-9877(90)90099-z
更新日期：1990-08-01 00:00:00
abstract：:Calcification is the most characteristic pathologic feature of healed meconium peritonitis. Occurrence of calcification in meconium peritonitis has been reported, but its mechanism has not been discussed. According to our studies, the cause of calcification and giant cell reaction is meconium peritonitis is related to...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/0306-9877(84)90062-8
更新日期：1984-05-01 00:00:00
abstract：:The title enzyme, peptidylglycine alpha-hydroxylating monooxygenase (PHM), is essential to the in vivo generation of a wide variety of physiologically significant alpha-amidated peptide hormones from the corresponding C-terminal glycine-extended prohormones. Over a 20-year period of time a massive amount of experiment...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2003.11.012
更新日期：2004-01-01 00:00:00
abstract：:The therapeutic efficacy of thalidomide in erythema nodosum leprosum suggests that thalidomide might play a useful therapeutic role in other human immune-complex diseases. Thalidomide has shown anti-inflammatory or immunosuppressive actions in several animal models. Current evidence suggests that its rapid activity in...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/0306-9877(83)90009-9
更新日期：1983-04-01 00:00:00
abstract：:A birth involving shoulder dystocia can rapidly deteriorate-from a fetus with a reassuring tracing in the minutes before birth, to a neonate needing aggressive resuscitation. Infants experiencing a traumatic birth involving shoulder dystocia may be severely compromised, even when the preceding labor was uncomplicated....
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2008.11.019
更新日期：2009-04-01 00:00:00
abstract：:Howard Gardner identified five different kinds of creative activity among eminent creators, namely, solving a well-defined problem, putting forth a general conceptual scheme, creating a product that embodies ideas, stylized innovation of an art form, and a 'high-stakes' performance in the socio-political arena. In thi...
journal_title：Medical hypotheses
pub_type： 传,历史文章,杂志文章
doi：10.1054/mehy.1998.0777
更新日期：1999-10-01 00:00:00
abstract：:Is sleep especially beneficial in times of illness? Despite the widespread use of hypnotics, the medical position on this question is equivocal, for hospital practices seem rarely designed to encourage maximum sleeping. Sleep promotion is defined as the arrangement of conditions so that patients can achieve as much sl...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/0306-9877(84)90005-7
更新日期：1984-09-01 00:00:00
abstract：:Chronic viral liver disease may evolve to cirrhosis. The medical treatment to slow down this passage is based on anti-viral and anti-fibrotic properties of interferon. Recently, we evidenced significant increase of portal vein flow velocity and volume after a prostacyclin analog (iloprost) infusion in subjects without...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2004.05.017
更新日期：2005-01-01 00:00:00
abstract：:Memory is a complex cognition that plays a critical role in daily functioning. This review discusses the dynamic effects of acute exercise on memory function, via a hypothesized exercise-memory interaction model, taking into consideration multiple memory systems and exercise parameters. ...
journal_title：Medical hypotheses
pub_type： 杂志文章,评审
doi：10.1016/j.mehy.2019.03.010
更新日期：2019-05-01 00:00:00
abstract：:We describe a new term: glutamate-based depression (GBD). GBD is defined as a chronic depressive illness associated with environmental stress and diseases associated with altered glutamate neurotransmission. We hypothesize that glutamate-induced over-activation of extrasynaptic NMDA receptors in the subgenual cingulat...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2012.02.009
更新日期：2012-05-01 00:00:00
abstract：:What causes cancer? To date, this question is left with no answer. The scientific community keeps defining cancer as a proliferation of cells in an uncontrolled and uncontrollable manner. The hypothesis developed here through an understanding of the cancer cell's behaviour led to its re-definition, providing answers t...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1054/mehy.2001.1532
更新日期：2002-06-01 00:00:00
abstract：:To discuss the possible pathogenesis of outlet obstructive constipation (OOC) and identify the theoretical basis of the Procedure for Prolapse and Hemorrhoids (PPH) used to treat outlet obstructive constipation (OOC). 19 patients diagnosed with outlet obstructive constipation (OOC) form the case group, and 9 healthy v...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2015.03.022
更新日期：2015-07-01 00:00:00
abstract：:In both African AIDS populations and homosexual populations outside of Africa, a high incidence of syphilis and multiple exposures to infectious diseases results in frequent, often abusive use of antibiotics. Epidemiological evidence exists for chemical immunosuppression resulting from antibiotics and other prescribed...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/0306-9877(86)90036-8
更新日期：1986-12-01 00:00:00
abstract：:The pancreatic leakage is a lethal postoperative complication to the patients after duodenopancreatectomy for carcinoma of head of pancreas. However, we found that the patients who survived this lethal postoperative complication could potentially acquire a longer survival time comparing with those without postoperativ...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2009.02.024
更新日期：2009-08-01 00:00:00
abstract：:Goldberger discovered human pellagra was a non-infectious disease, affecting mostly the small and the timid in overcrowded institutions. Symptoms were diarrhoea, dermatitis and dementia. The staff and older children escaped the disease. They ate the meat and left the small and timid with the gravy. The 'Goldberger syn...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/0306-9877(93)90009-f
更新日期：1993-05-01 00:00:00
abstract：:Cocaine is one of the principal drugs of abuse. Although impressive advances have been made, unanswered questions remain concerning mechanism of toxicity and addiction. Discussion of action mode usually centers on receptor binding and enzyme inhibition, with limited attention to events at the molecular level. This rev...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2004.06.028
更新日期：2005-01-01 00:00:00
abstract：:Mandibular asymmetry (MA) is one of the most common craniofacial malformations. However, there is no optimal technique for this malformation nowadays. A novel technique for both children and adults with less disadvantages is a must. Parathyroid hormone (PTH) is a straight-chain polypeptide secreted by the parathyroid ...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1016/j.mehy.2009.10.047
更新日期：2010-04-01 00:00:00
abstract：:Epidemiological findings on the relation between foods and colon cancer are inconsistent. Many, but far from all, found positive associations for meat and fat and negative ones for vegetables and fruits. Explanations so far have focused on direct biochemical conversions in the colon or transit time, but they remain un...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1054/mehy.1999.0878
更新日期：2000-03-01 00:00:00
abstract：:Recent studies using a combination of isotope and balance techniques have shown that, in the postabsorptive state, the human kidney contributes substantially to overall glucose production and consumption. The kidney may contribute as much as the liver to gluconeogenesis and play an important role in the counterregulat...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1054/mehy.1997.0655
更新日期：1999-05-01 00:00:00
abstract：:The paradigm of an immune system presumes that a system arose specifically to combat infection -- hence its name. This paradigm gained credibility with the discovery of antibodies and anamnestic immunity, even though these are relatively late arrivals in evolution. Another presumption has been that thymus-dependent T ...
journal_title：Medical hypotheses
pub_type： 杂志文章
doi：10.1054/mehy.1997.0645
更新日期：1999-03-01 00:00:00
