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1.
Cervical cancer can be not only prevented, but also effectively treated. Decreased efficiency of biochemical, neurohormonal and/or immunological mechanisms leads to infectious states which, irrespective of their bacterial, viral or parasitic aetiology, are only the necessary, but not the sufficient causes of neogenesis. The cause of cancer is the natural and common phenomenon of the self-organization of systems, endangered by ending of their existence, into more efficient time-space structures at the expense of their surrounding. Infected cells or infectiously changed tissues in their final phase of existence are often recognized as a precancerous state, but their genome does not differ from other organism cells, and that is why the carcinogenesis can still be prevented by direct fighting of pathogenic microorganisms, and indirectly by strengthening the body by neurohormonal therapy or vaccine immunopotentialization. Primary prophylaxis of neoplasms requires that not only the dissipathogenic state of cells be prevented, but also their tissue surrounding be normalized to head off the risk of the self-organization of neoplastic forms of life, differing in their genetic identity from the surrounding cells. Lactovaginal immunopotentialization complements the conservative and operative methods of oncological treatment, as well as has prophylactic application in women with the history of miscarriages, premature deliveries, lack of or significantly shortened lactation, neurohormonal menstruating disorders, chronic and recurrent inflammations of the reproductive organs, long-term hormonal contraception and hormone replacement therapy during menopause, or only deficiency of Lactobacillus vaginalis, as indicators of risk of cervical cancer.  相似文献   

2.
The essence of life is best manifested in cell, which, when brought to the edge of its existence in the actual environment may and sometimes must self-organise into an entirely different cell (neoplasm), but it must enhance dissipation of matter and energy in its closest environment. This phenomenon has been described before as self-organisation of dissipative structures in physics, chemistry and even sociology. Each neoplastic cell is such a dissipative system - with its clonal growth, the cell causes increasing disorganisation of the body, in consequence leading to neoplastic disease. The only adequate cause of formation of neoplasms is an internal dissipathogenic cellular state, which is clinically identify as preneoplastic ones at the level of morphology or molecular biology but also biophysics. Two general directions for therapy of neoplastic diseases arise from the thermodynamic essence of neogenesis: the direct one - targeting neoplasms, and the indirect one - leading to normalisation or sufficient alteration of their environment. The greatest disappointment in the fight against neoplasm was the discovery of its thermodynamic cause in a natural self-organisation of biological dissipative structures. It is this dissipation that causes the signs and symptoms of neoplastic diseases ending with destruction of the body if the treatment comes too late and/or is insufficient, limited only to removal of neoplastic lesions without the always necessary elimination and/or prevention of preneoplastic (dissipathogenic) states.  相似文献   

3.
This study explores the origin of primordial germ cells (PGCs) of the mouse and examines their morphology and associations with other cells during early development. PGCs have been selectively stained by the alkaline phosphatase histochemical reaction and viewed by light and electron microscopy from the time they are first detectable in the yolk sac endoderm until they enter the gonadal ridges. There are conflicting reports as to whether the PGCs originate from endodermal cells or whether they originate elsewhere and subsequently enter the endoderm. The observations in the present study favor the premise that PGCs of the mouse do not originate in the endoderm. Furthermore, it was observed that PGCs undergo specific changes in morphology during the developmental period studied and this was interpreted to mean that, although PGCs are set aside early in development as a distinct cell line, they also continue to become more specialized within time. The germ cell line is rather unusual in that it does not exist as a discrete tissue but, instead, resides within various other tissues during its life history. This apparent dependence upon somatic cells is maintained even in adult animals and may be important in serving to maintain or modify the environment of the germ cells.  相似文献   

4.
Biofilms, or surface-attached microbial communities, are both ubiquitous and resilient in the environment. Although much is known about how biofilms form, develop, and detach, very little is understood about how these events are related to metabolism and its dynamics. It is commonly thought that large subpopulations of cells within biofilms are not actively producing proteins or generating energy and are therefore dead. An alternative hypothesis is that within the growth-inactive domains of biofilms, significant populations of living cells persist and retain the capacity to dynamically regulate their metabolism. To test this, we employed unstable fluorescent reporters to measure growth activity and protein synthesis in vivo over the course of biofilm development and created a quantitative routine to compare domains of activity in independently grown biofilms. Here we report that Shewanella oneidensis biofilm structures reproducibly stratify with respect to growth activity and metabolism as a function of size. Within domains of growth-inactive cells, genes typically upregulated under anaerobic conditions are expressed well after growth has ceased. These findings reveal that, far from being dead, the majority of cells in mature S. oneidensis biofilms have actively turned-on metabolic programs appropriate to their local microenvironment and developmental stage.  相似文献   

5.
In Western countries a considerable number of older people move to a residential home when their health declines. Institutionalization often results in increased dependence, inactivity and loss of identity or self-worth (dignity). This raises the moral question as to how older, institutionalized people can remain autonomous as far as continuing to live in line with their own values is concerned. Following Walker's meta-ethical framework on the assignment of responsibilities, we suggest that instead of directing all older people towards more autonomy in terms of independence, professional caregivers should listen to the life narrative of older people and attempt to find out how their personal identity, relations and values in life can be continued in the new setting. If mutual normative expectations between caregivers and older people are not carefully negotiated, it creates tension. This tension is illustrated by the narrative of Mr Powell, a retired successful public servant now living in a residential home. The narrative describes his current life, his need for help, his independent frame of mind, and his encounters with institutional and professional policies. Mr Powell sees himself as a man who has always cared for himself and others, and who still feels that he has to fulfil certain duties in life. Mr Powell's story shows that he is not always understood well by caregivers who respond from a one-sided view of autonomy as independence. This leads to misunderstanding and an underestimation of his need to be noticed and involved in the residential community.  相似文献   

6.
The maternal care that offspring receive from their mothers early in life influences the offspring’s development of emotional behavior in adulthood. Here we found that offspring reared by circadian clock-impaired mice show elevated anxiety-related behavior. Clock mutant mice harboring a mutation in Clock, a key component of the molecular circadian clock, display altered daily patterns of nursing behavior that is fragmented during the light period, instead of long bouts of nursing behavior in wild-type mice. Adult wild-type offspring fostered by Clock mutant mice exhibit increased anxiety-related behavior. This is coupled with reduced levels of brain serotonin at postnatal day 14, whose homeostasis during the early postnatal period is critical for normal emotional behavior in adulthood. Together, disruption of the circadian clock in mothers has an adverse impact on establishing normal anxiety levels in offspring, which may increase their risk of developing anxiety disorders.  相似文献   

7.
During its lifetime each multi-cellular organism is permanently exposed to infectious agents and transformed cells. Without an early recognition and a rapid elimination system, there would be no development and no life. The innate or natural immunity, seems to be more important for the detection of "foreign" cells and particles than has been thought. Even if not every transformed cell has the ability and potency for malignant behaviour, the important question is not, why malignant cells arise, but instead, why malignancy occurs so infrequently. We have shown in a recent paper, by using the human hybridoma technology, that tumour immunity is not induced by malignant cells, but instead the result of innate immunity and that natural IgM antibodies play an important role in immunosurveillance mechanisms against transformed cells in humans (Br?ndlein et al., 2003b). In this review typical features of natural IgM antibodies are discussed and tumour-specific reactivities and different apoptotic functions on epithelial cancer cells are illustrated.  相似文献   

8.
It is increasingly accepted that alterations of the intrauterine and early postnatal nutritional, metabolic and hormonal environment may predispose individuals to development of diseases in later life. Results from studies of the offspring of diabetic mothers strongly support this hypothesis. It has also been suggested that being light at birth leads to an increased risk of the metabolic syndrome (Syndrome X) in later life (the Barker hypothesis). The pathophysiological mechanisms that underlie this programming are unclear. However, hormones are important environment-dependent organizers of the developing neuroendocrine-immune network, which regulates all the fundamental processes of life. Hormones can act as 'endogenous functional teratogens' when present in non-physiological concentrations, induced by alterations in the intrauterine or neonatal environment during critical periods of perinatal life. Perinatal hyperinsulinism is pathognomic in offspring of diabetic mothers. Early hyperinsulinism also occurs as a result of early postnatal overfeeding. In rats, endogenous hyperinsulinism, as well as peripheral or intrahypothalamic insulin treatment during perinatal development, may lead to 'malprogramming' of the neuroendocrine systems regulating body weight, food intake and metabolism. This results in an increased disposition to become obese and to develop diabetes throughout life. Similar malprogramming may occur due to perinatal hypercortisolism and hyperleptinism. With regard to 'small baby syndrome' and the thrifty phenotype hypothesis, we propose that early postnatal overfeeding of underweight newborns may substantially contribute to their long-term risk of obesity and diabetes. In summary, a complex malprogramming of the central regulation of body weight and metabolism may provide a general aetiopathogenetic concept, explaining perinatally acquired disposition to later disease and, thereby, opening a wide field for primary prevention.  相似文献   

9.
C L Keen 《Teratology》1992,46(1):15-21
A review of current literature suggests that maternal nutritional status can be an important modulator of the developmental toxicity of a number of agents in the environment. While the provision of multivitamin/multimineral supplements during the periconceptional period is often associated with improved pregnancy outcome, it has been difficult to identify specific nutrient deficiencies as causative factors of abnormal development in humans. One explanation for this is that nutrient deficiencies can arise through a number of means in addition to a simple dietary deficit of the nutrient. The hypothesis is proposed that one mechanism contributing to the embryotoxicity of a diverse group of insults is an alteration in the metabolism of select nutrients. Evidence is presented that zinc is one nutrient whose metabolism can be markedly influenced by a variety of insults. One consequence of this alteration can be a reduction in embryonic zinc uptake, the development of embryonic zinc deficiency and abnormal development.  相似文献   

10.
11.
Spatiometabolic Stratification of Shewanella oneidensis Biofilms   总被引:1,自引:0,他引:1       下载免费PDF全文
Biofilms, or surface-attached microbial communities, are both ubiquitous and resilient in the environment. Although much is known about how biofilms form, develop, and detach, very little is understood about how these events are related to metabolism and its dynamics. It is commonly thought that large subpopulations of cells within biofilms are not actively producing proteins or generating energy and are therefore dead. An alternative hypothesis is that within the growth-inactive domains of biofilms, significant populations of living cells persist and retain the capacity to dynamically regulate their metabolism. To test this, we employed unstable fluorescent reporters to measure growth activity and protein synthesis in vivo over the course of biofilm development and created a quantitative routine to compare domains of activity in independently grown biofilms. Here we report that Shewanella oneidensis biofilm structures reproducibly stratify with respect to growth activity and metabolism as a function of size. Within domains of growth-inactive cells, genes typically upregulated under anaerobic conditions are expressed well after growth has ceased. These findings reveal that, far from being dead, the majority of cells in mature S. oneidensis biofilms have actively turned-on metabolic programs appropriate to their local microenvironment and developmental stage.  相似文献   

12.
Experimental studies demonstrated that maternal exposure to certain environmental and dietary factors during early embryonic development can influence the phenotype of offspring as well as the risk of disease development at the later life. DNA methylation, an epigenetic phenomenon, has been suggested as a mechanism by which maternal nutrients affect the phenotype of their offspring in both honeybee and agouti mouse models. Phenotypic changes through DNA methylation can be linked to folate metabolism by the knowledge that folate, a coenzyme of one-carbon metabolism, is directly involved in methyl group transfer for DNA methylation. During the fetal period, organ-specific DNA methylation patterns are established through epigenetic reprogramming. However, established DNA methylation patterns are not immutable and can be modified during our lifetime by the environment. Aberrant changes in DNA methylation with diet may lead to the development of age-associated diseases including cancer. It is also known that the aging process by itself is accompanied by alterations in DNA methylation. Diminished activity of DNA methyltransferases (Dnmts) can be a potential mechanism for the decreased genomic DNA methylation during aging, along with reduced folate intake and altered folate metabolism. Progressive hypermethylation in promoter regions of certain genes is observed throughout aging, and repression of tumor suppressors induced by this epigenetic mechanism appears to be associated with cancer development. In this review, we address the effect of folate on early development and aging through an epigenetic mechanism, DNA methylation.  相似文献   

13.
ROLE OF FETAL AND INFANT GROWTH IN PROGRAMMING METABOLISM IN LATER LIFE   总被引:6,自引:0,他引:6  
Fetal growth and development is dependent upon the nutritional, hormonal and metabolic environment provided by the mother. Any disturbance in this environment can modify early fetal development with possible long-term outcomes as demonstrated by extensive work on ‘programming’. Growth restriction resulting from a deficit in tissue/organ cell number (as measured by tissue DNA content) is irrecoverable. However, when the cell size (or cell protein content) is reduced, the effects on growth may not be permanent. Recent epidemiological studies using archival records of anthropometric measurements related to early growth in humans have shown strong statistical associations between these indices of early development and diseases in later life. It has been hypothesised that the processes explaining these associations involve adaptive changes in fetal organ development in response to maternal and fetal malnutrition. These adaptations may permanently alter adult metabolism in a way which is beneficial to survival under continued conditions of malnutrition but detrimental when nutrition is abundant. This hypothesis is being tested in a rat model which involves studying the growth and metabolism in the offspring of rat dams fed a low-protein diet during pregnancy and/or lactation. Using this rat model, it has been demonstrated that there is:
  • (i) Permanent growth retardation in offspring nursed by dams fed a low-protein diet.
  • (ii) Permanent and selective changes in organ growth. Essential organs like the brain and lungs are relatively protected from reduction in growth at the expense of visceral organs such as the liver, pancreas, muscle and spleen.
  • (iii) Programming of liver metabolism as reflected by permanent changes in activities of key hepatic enzymes of glycolysis and gluconeogenesis (glucokinase and phosphoenolpyruvate carboxykinase) in a direction which would potentially bias the liver towards a ‘starved’ setting. We have speculated that these changes could be a result of altered periportal and perivenous regions of the liver which may also affect other aspects of hepatic function.
  • (iv) Deterioration in glucose tolerance with age.
  • (v) An increase in the life span of offspring exposed to maternal protein restriction only during the lactation period, and a decrease in life span when exposed to maternal protein restriction only during gestation.
These studies show that hepatic metabolism and even longevity can be programmed by events during early life.  相似文献   

14.
The ciliary marginal zone (CMZ) of fish and frog retinas contains cells that proliferate throughout postembryonic development as the retina grows with increasing body size, indicating the presence of stem cells in this region. However, neither the location nor the molecular identity of retinal stem cells has been identified. Here, we show in Xenopus that c-myc and n-myc are sequentially expressed both during development and in the post-embryonic retina. The c-myc+/n-myc- cells near the extreme periphery of the CMZ cycle more slowly and preferentially retain DNA label compared to their more central cmyc+/n-myc+ neighbors which cycle rapidly and preferentially dilute DNA label. During retinal development c-myc is functionally required earlier than n-myc, and n-myc expression depends on earlier c-myc expression. The expression of c-myc but not n-myc in the CMZ depends on growth factor signaling. Our results suggest that c-myc+/n-myc- cells in the far peripheral CMZ are candidates for a niche-dependent population of retinal stem cells that give rise to more centrally located and rapidly dividing n-myc+ progenitors of more limited proliferative potential. Analysis of homologues of these genes in the zebrafish CMZ suggests that the transition from c-myc to n-myc expression might be conserved in other lower vertebrates whose retinas growth throughout life.  相似文献   

15.
The insecticide dichlorodiphenyltrichloroethane (DDT) is persistent in the environment, and continues to cause health problems. Tetrahymena has potential as a model organism for assaying low levels of DDT and for analysing the mechanisms of its toxicity. We constructed the suppression subtractive hybridization library of T. thermophila exposed to DDT, and screened out 90 Expressed Sequence Tags whose expressions were significantly up- or downregulated with DDT treatment. From this, a series of important genes related to the DDT metabolism and detoxification were discovered, such as P450 gene, glutathione S-transferase gene and sterol carrier protein 2 gene. Furthermore, their expressions under different concentrations of DDT treatment were detected by real-time fluorescent quantitative PCR. The results show that Tetrahymena is a relevant and useful model organism for detecting DDT in the environment and for discovering biomarkers that can be used to develop specific bio-reporters at the molecular and genomic levels.  相似文献   

16.
The uridylic acid rich nuclear RNAs (U1-U6 snRNAs) are involved mainly in the processing of pre-mRNA and pre-rRNA. So, any control of cell growth through pre-mRNA/pre-rRNA processing may have some regulation through altered UsnRNAs metabolism. With this idea, attempts have been made to see how the metabolism of the six major UsnRNAs' changed during the normal process of cellular proliferation associated with differentiation from pluripotent/totipotent stem cells of early embryonic stage to much more differentiated state of different cell/tissue lineages in different tissues/organs during the fetal and neonatal stages of growth. It has been seen that the levels of the six major UsnRNAs were high in day 8 embryo when the cells were mainly pluripotent/totipotent in nature, and during the progression of embryonic development the levels of these UsnRNAs gradually decreased (35-65%) up to the midgestational period (day 13) with some exception, when the organogenesis has already been started. However in the fetal life, the levels of these UsnRNAs were maximum or comparable around 18 ± 2 days of gestation in comparison to that in day 8 embryo when the kinetics of the maturational status of the different organs were quite high. But, the levels of these UsnRNAs' became low during day 21 of fetal life or in day 0 of birth (perturation period) in all the tissues/organs except high UsnRNAs' level in spleen. In the neonatal life, around 3 ± 1 days of birth these UsnRNAs' levels again became maximum in all the tissues/organs (except in thymus) followed by decrease up to 5/6 days, and to become steady with slight increase within one to two weeks, when the kinetics of the organ maturation reached to a steady state. In case of thymus, the levels of the U3-U6 snRNAs were high on day 0 of birth followed by decrease in their level on day 1/2 and then increased to become steady within 2-4 weeks; whereas the U1 and U2 snRNAs' levels were high on day 3 of birth and the subsequent changes were similar to that in other tissues/organs.Thus the different UsnRNAs' metabolism in the perturation period and in the early stages of neonatal life has indicated the differential cellular functions in these two stages of development. These alterations in the metabolism of these UsnRNAs might be due to the differential changes in the rate of synthesis of these UsnRNAs and/or with their differential turnover rate in the different stages of development. Also, the differential variations of these UsnRNAs' levels have been observed among the different tissues/organs at the respective stages of development indicating the differences in the UsnRNAs' metabolism among the different cell/tissue lineages. Thus, it can be concluded that the metabolism of these UsnRNAs were developmentally regulated with some cell/tissue lineage variations, which might have some role in the developmentally regulated cellular process of proliferation and differentiation, through altered RNA splicing and processing.  相似文献   

17.
The exposure of isolated and cultured cells to oxygen free radicals generated extracellularly or intracellularly during the metabolism of foreing compounds results in the development of damage that eventually lead to cell death. Multiple mechanisms are involved in these cytopathological processes, including direct attack of free radicals to macromolecules essential for cell life, as well as indirect activation of catabolic processes such as proteases, endonucleases and phospholipases. A key role in triggering these indirect events is played by Ca2+ whose cytosolic concentration during oxidative stress raises well above the physiological limits.  相似文献   

18.
A halophilic bacterium was isolated from fermented seafood. The 16S rDNA sequence identity between the isolate and Halomonas subglaciescola AJ306801 was above 95%. The isolate that did not grow in the condition without NaCl or in the condition with other sodium (Na+) or chloride ions (Cl-) instead of NaCl was named H. subglaciescola DH-1. Two mutants capable of growing without NaCl were obtained by random mutagenesis, of which their total soluble protein profiles were compared with those of the wild type by two-dimensional electrophoresis. The external compatible solutes (betaine and choline) and cell extract of the wild type did not function as osmoprotectants, and these parameters within the mutants did not enhance their growth in the saline environment. In the proton translocation test, rapid acidification of the reactant was not detected for the wild type, but it was detected for the mutant in the condition without NaCl. From these results, we derived the hypothesis that NaCl may be absolutely required for the energy metabolism of H. subglaciescola DH-1 but not for its osmoregulation, and the mutants may have another modified proton translocation system that is independent of NaCl, except for those mutants with an NaCl-dependent system.  相似文献   

19.
Cross-regulatory effects of immune and neuroendocrine systems on their appearance and functioning occur during a whole life period. At different stages of ontogenesis, the functions of these systems are diverse. In perinatal ontogenesis hormones, neuropeptides and neurotransmitters control the processes of growth and differentiation of various embryo tissues, particularly lymphoid. In the postnatal period, their functions are mostly in homeostasis maintaining of the immune system in response to changes of the environment. Conversely, transmitters of the immune system, such as cytokines, whose synthesis is increased in inflammation, and thymic peptides, program the development of the neuroendocrine system of the embryo. The perinatal period is crucial for final appearance of these systems. Changes in one of the interacting systems, caused by negative environmental factors at this stage, usually provoke changes in other developing systems for a long period. Plasticity of physiological systems in perinatal development allows the organism to adapt to changed conditions. However, these changes can limit physiological functions in interacting systems and induce the appearance of various pathologies in postnatal life.  相似文献   

20.
Maternal effects have gained attention as a method by which mothers may alter the physiological condition and phenotype of their offspring based upon current environmental conditions. The physiological and phenotypic outcomes of glucocorticoid-mediated maternal effects have been extensively studied in a variety of vertebrates; however, the underlying mechanism is currently unclear. Here, we injected tritiated corticosterone into the yolks of freshly laid Japanese quail eggs (Coturnix japonica) and traced its movement and metabolism through the in ovo development period. We found that corticosterone was extensively conjugated throughout the egg by the end of development, and while minimal corticosterone was detected within the embryo during development, accumulation of a conjugated metabolite in the embryo started to occur on day 6 of development. Because no movement and metabolism of corticosterone occurred in infertile eggs, our findings suggest that embryos are not passive recipients of maternal steroids, but instead appear to possess extensive metabolic capabilities, which may modulate their exposure to maternal steroids.  相似文献   

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