Pub Date : 2007-09-28DOI: 10.1002/9780470514474.CH9
Anupam Varma
Viral diseases of plants cause enormous economic losses particularly in the tropics and semitropics which provide ideal conditions for the perpetuation of viruses and their vectors. Intensive agricultural practices necessitated by the ever-increasing demands of the rapidly growing population and the introduction of new genotypes, cropping patterns and crops have further aggravated the problem of viral diseases. Many diverse approaches have been tried to minimize the losses caused by these diseases. The approaches are mainly based on avoidance of sources of infection; avoidance or control of vectors; modification of cultural practices; use of resistant varieties obtained though conventional breeding procedures; cross protection; systemic acquired resistance; and use of transgenic plants containing alien genes that impart resistance to viruses. Although the use of resistant varieties has been found to be the most economical and practical, for effective management of viral diseases an integrated approach is essential in sustainable agriculture. Development of integrated management practices also requires correct identification of the causative viruses, because symptoms can be misleading, and adequate understanding of the ecology of viruses and their vectors.
{"title":"Integrated management of plant viral diseases.","authors":"Anupam Varma","doi":"10.1002/9780470514474.CH9","DOIUrl":"https://doi.org/10.1002/9780470514474.CH9","url":null,"abstract":"Viral diseases of plants cause enormous economic losses particularly in the tropics and semitropics which provide ideal conditions for the perpetuation of viruses and their vectors. Intensive agricultural practices necessitated by the ever-increasing demands of the rapidly growing population and the introduction of new genotypes, cropping patterns and crops have further aggravated the problem of viral diseases. Many diverse approaches have been tried to minimize the losses caused by these diseases. The approaches are mainly based on avoidance of sources of infection; avoidance or control of vectors; modification of cultural practices; use of resistant varieties obtained though conventional breeding procedures; cross protection; systemic acquired resistance; and use of transgenic plants containing alien genes that impart resistance to viruses. Although the use of resistant varieties has been found to be the most economical and practical, for effective management of viral diseases an integrated approach is essential in sustainable agriculture. Development of integrated management practices also requires correct identification of the causative viruses, because symptoms can be misleading, and adequate understanding of the ecology of viruses and their vectors.","PeriodicalId":10218,"journal":{"name":"Ciba Foundation symposium","volume":"115 1","pages":"140-55; discussion 155-7"},"PeriodicalIF":0.0,"publicationDate":"2007-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73706173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-28DOI: 10.1002/9780470514658.CH2
R. B. Merrifield, E. Merrifield, P. Juvvadi, D. Andreu, H. G. Boman
The cecropins are a group of potent antimicrobial peptides, initially discovered in insects but later found in other animals including mammals. Synthetic peptide chemistry has played an important role in establishing their primary sequences, as well as the steps in the processing of the biosynthetic preprocecropins. Solid-phase peptide synthesis has been the method of choice. Synthetic chimeric peptides have led to more active products and a better understanding of their mode of action. The structural requirements for high activity include a basic amphipathic N-terminus, a short central flexible sequence and a hydrophobic helical C-terminus. Cecropin-melittin hybrids as small as 15 residues are highly active. In planar lipid bilayers the cecropins form pores which pass ions and carry a current under a voltage gradient. Synthetic D-enantiomers of several antibacterial peptides carry the same current as the natural all-L-peptides and are equally active against several test bacteria. Therefore, the activity is not dependent on chiral interactions between the peptides and the lipid bilayers or the bacterial membranes. Recent examination of retro and retroenantio peptides has further defined the limits of the structural requirements of these peptides. Some of the hybrid peptides are active against Plasmodium falciparum and Mycobacterium smegmatis.
{"title":"Design and synthesis of antimicrobial peptides.","authors":"R. B. Merrifield, E. Merrifield, P. Juvvadi, D. Andreu, H. G. Boman","doi":"10.1002/9780470514658.CH2","DOIUrl":"https://doi.org/10.1002/9780470514658.CH2","url":null,"abstract":"The cecropins are a group of potent antimicrobial peptides, initially discovered in insects but later found in other animals including mammals. Synthetic peptide chemistry has played an important role in establishing their primary sequences, as well as the steps in the processing of the biosynthetic preprocecropins. Solid-phase peptide synthesis has been the method of choice. Synthetic chimeric peptides have led to more active products and a better understanding of their mode of action. The structural requirements for high activity include a basic amphipathic N-terminus, a short central flexible sequence and a hydrophobic helical C-terminus. Cecropin-melittin hybrids as small as 15 residues are highly active. In planar lipid bilayers the cecropins form pores which pass ions and carry a current under a voltage gradient. Synthetic D-enantiomers of several antibacterial peptides carry the same current as the natural all-L-peptides and are equally active against several test bacteria. Therefore, the activity is not dependent on chiral interactions between the peptides and the lipid bilayers or the bacterial membranes. Recent examination of retro and retroenantio peptides has further defined the limits of the structural requirements of these peptides. Some of the hybrid peptides are active against Plasmodium falciparum and Mycobacterium smegmatis.","PeriodicalId":10218,"journal":{"name":"Ciba Foundation symposium","volume":"1 1","pages":"5-20; discussion 20-6"},"PeriodicalIF":0.0,"publicationDate":"2007-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82306174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-28DOI: 10.1002/9780470513828.CH15
M. Fukuda
We have isolated a major sialoglycoprotein on leucocytes and found that this glycoprotein, termed leukosialin, is ubiquitously present on various human leucocytes (granulocytes, monocytes/macrophages and T lymphocytes). Our studies showed that leukosialin is significantly glycosylated by O-linked oligosaccharides (70 chains/molecule). The polypeptide portions of these molecules are, however, apparently the same, with a molecular mass of 38.5 kDa. The amino acid sequence derived from cDNA shows tandemly repeated O-glycan attachment sequences, and about 70% of the serine or threonine residues in the external domain are modified by O-glycans. The structures of those O-linked oligosaccharides are characteristic of each cell lineage and maturation stage. In particular, we have shown that O-glycans of leukosialin are converted from NeuAc(alpha 2-3)Gal(beta 1-3) [NeuAc(alpha 2-6)]-GalNAc to NeuAc(alpha 2-3)Gal(beta 1-3) [NeuAc(alpha 2-3)Gal(beta 1-4)GlcNAc(beta 1-6)] GalNAc during T cell activation.
{"title":"Leukosialin, a major sialoglycoprotein defining leucocyte differentiation.","authors":"M. Fukuda","doi":"10.1002/9780470513828.CH15","DOIUrl":"https://doi.org/10.1002/9780470513828.CH15","url":null,"abstract":"We have isolated a major sialoglycoprotein on leucocytes and found that this glycoprotein, termed leukosialin, is ubiquitously present on various human leucocytes (granulocytes, monocytes/macrophages and T lymphocytes). Our studies showed that leukosialin is significantly glycosylated by O-linked oligosaccharides (70 chains/molecule). The polypeptide portions of these molecules are, however, apparently the same, with a molecular mass of 38.5 kDa. The amino acid sequence derived from cDNA shows tandemly repeated O-glycan attachment sequences, and about 70% of the serine or threonine residues in the external domain are modified by O-glycans. The structures of those O-linked oligosaccharides are characteristic of each cell lineage and maturation stage. In particular, we have shown that O-glycans of leukosialin are converted from NeuAc(alpha 2-3)Gal(beta 1-3) [NeuAc(alpha 2-6)]-GalNAc to NeuAc(alpha 2-3)Gal(beta 1-3) [NeuAc(alpha 2-3)Gal(beta 1-4)GlcNAc(beta 1-6)] GalNAc during T cell activation.","PeriodicalId":10218,"journal":{"name":"Ciba Foundation symposium","volume":"1 1","pages":"257-68; discussion 268-76"},"PeriodicalIF":0.0,"publicationDate":"2007-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83102714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-28DOI: 10.1002/9780470515303.CH5
J. Elliott
The apatitic calcium phosphate crystals in dental enamel are too small for single crystal diffraction studies so the only possible direct structure determination must use whole-pattern-fitting Rietveld analysis of X-ray and neutron powder diffraction patterns. As a result, aspects of the structure are not known in detail. Further structural information can be obtained by consideration of published chemical analyses and infrared studies, taking into account studies of the crystal chemistry of synthetic apatitic analogues of enamel apatite. The apatitic constitutional water and total water content of enamel are particularly important, but there are difficulties in their determination. Making reasonable assumptions, a number of models of the unit cell can be derived. The weight per cent (including constitutional water) and density of the enamel apatite crystals for the most probable model are about 98 wt.% and 3.0 g cm-3, respectively. The apatite volume per cent calculated from these values is about 96%. The weight per cent and volume per cent of enamel apatite are higher than normally accepted values because of inclusion of constitutional water and use of a density for enamel apatite that takes into account its known lattice expansion over hydroxyapatite and probable lattice vacancies.
牙釉质中的磷灰质磷酸钙晶体太小，无法进行单晶衍射研究，因此唯一可能的直接结构测定必须使用x射线和中子粉末衍射图的整体模式拟合Rietveld分析。因此，该结构的各个方面都不为人所知。进一步的结构信息可以通过考虑已发表的化学分析和红外研究来获得，并考虑到珐琅磷灰石的合成磷灰石类似物的晶体化学研究。牙釉质的灰质构成水和总含水量尤为重要，但测定困难。通过合理的假设，可以推导出许多单元胞的模型。最可能模型的搪瓷磷灰石晶体的重量百分比(包括本构水)和密度分别约为98 wt.%和3.0 g cm-3。由这些数值计算得出的磷灰石体积百分比约为96%。搪瓷磷灰石的重量百分比和体积百分比比通常接受的值要高，因为包含了构成水，并且使用了搪瓷磷灰石的密度，考虑了它在羟基磷灰石上已知的晶格膨胀和可能的晶格空缺。
{"title":"Structure, crystal chemistry and density of enamel apatites.","authors":"J. Elliott","doi":"10.1002/9780470515303.CH5","DOIUrl":"https://doi.org/10.1002/9780470515303.CH5","url":null,"abstract":"The apatitic calcium phosphate crystals in dental enamel are too small for single crystal diffraction studies so the only possible direct structure determination must use whole-pattern-fitting Rietveld analysis of X-ray and neutron powder diffraction patterns. As a result, aspects of the structure are not known in detail. Further structural information can be obtained by consideration of published chemical analyses and infrared studies, taking into account studies of the crystal chemistry of synthetic apatitic analogues of enamel apatite. The apatitic constitutional water and total water content of enamel are particularly important, but there are difficulties in their determination. Making reasonable assumptions, a number of models of the unit cell can be derived. The weight per cent (including constitutional water) and density of the enamel apatite crystals for the most probable model are about 98 wt.% and 3.0 g cm-3, respectively. The apatite volume per cent calculated from these values is about 96%. The weight per cent and volume per cent of enamel apatite are higher than normally accepted values because of inclusion of constitutional water and use of a density for enamel apatite that takes into account its known lattice expansion over hydroxyapatite and probable lattice vacancies.","PeriodicalId":10218,"journal":{"name":"Ciba Foundation symposium","volume":"67 1","pages":"54-67; discussion 67-72"},"PeriodicalIF":0.0,"publicationDate":"2007-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88452146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-28DOI: 10.1002/9780470513880.CH12
J. Groopman
Human retroviruses have been recognized for the last decade as pathogens for malignant or immunodeficient disease states. The human immunodeficiency virus (HIV) is the causal agent for the acquired immune deficiency syndrome (AIDS). Impaired haemopoiesis is common after HIV infection. The pathophysiology of this is not yet fully understood, but may involve direct retroviral infection of progenitors and/or elaboration of suppressor substances by accessory cells in the bone marrow microenvironment. Haemopoietic growth factors have been particularly useful in reconstituting myelopoiesis and erythropoiesis in HIV-infected patients with impaired bone marrow function.
{"title":"Retroviral infection and haemopoiesis.","authors":"J. Groopman","doi":"10.1002/9780470513880.CH12","DOIUrl":"https://doi.org/10.1002/9780470513880.CH12","url":null,"abstract":"Human retroviruses have been recognized for the last decade as pathogens for malignant or immunodeficient disease states. The human immunodeficiency virus (HIV) is the causal agent for the acquired immune deficiency syndrome (AIDS). Impaired haemopoiesis is common after HIV infection. The pathophysiology of this is not yet fully understood, but may involve direct retroviral infection of progenitors and/or elaboration of suppressor substances by accessory cells in the bone marrow microenvironment. Haemopoietic growth factors have been particularly useful in reconstituting myelopoiesis and erythropoiesis in HIV-infected patients with impaired bone marrow function.","PeriodicalId":10218,"journal":{"name":"Ciba Foundation symposium","volume":"9 1","pages":"173-80; discussion 180-5"},"PeriodicalIF":0.0,"publicationDate":"2007-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81791853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-28DOI: 10.1002/9780470514986.CH1
K. Stetter
Prokaryotes requiring extremely high growth temperatures (optimum 80-110 degrees C) have recently been isolated from water-containing terrestrial, subterranean and submarine high temperature environments. These hyperthermophiles consist of primary producers and consumers of organic matter, forming unique high temperature ecosystems. Surprisingly, within the 16S rRNA-based phylogenetic tree, hyperthermophiles occupy all the shortest and deepest branches closest to the root. Therefore, they appear to be the most primitive extant organisms. Most of them (the primary producers) are able to grow chemolithoautotrophically, using CO2 as sole carbon source and inorganic energy sources, suggesting a hyperthermophilic autotrophic common ancestor. They gain energy from various kinds of respiration. Molecular hydrogen and reduced sulfur compounds serve as electron donors while CO2, oxidized sulfur compounds, NO3- and O2 (only rarely) serve as electron acceptors. Growth demands of hyperthermophiles fit the scenario of a hot volcanism-dominated primitive Earth. Similar anaerobic chemolithoautotrophic hyperthermophiles, completely independent of a sun, could even exist on other planets provided that active volcanism and liquid water were present.
{"title":"Hyperthermophiles in the history of life.","authors":"K. Stetter","doi":"10.1002/9780470514986.CH1","DOIUrl":"https://doi.org/10.1002/9780470514986.CH1","url":null,"abstract":"Prokaryotes requiring extremely high growth temperatures (optimum 80-110 degrees C) have recently been isolated from water-containing terrestrial, subterranean and submarine high temperature environments. These hyperthermophiles consist of primary producers and consumers of organic matter, forming unique high temperature ecosystems. Surprisingly, within the 16S rRNA-based phylogenetic tree, hyperthermophiles occupy all the shortest and deepest branches closest to the root. Therefore, they appear to be the most primitive extant organisms. Most of them (the primary producers) are able to grow chemolithoautotrophically, using CO2 as sole carbon source and inorganic energy sources, suggesting a hyperthermophilic autotrophic common ancestor. They gain energy from various kinds of respiration. Molecular hydrogen and reduced sulfur compounds serve as electron donors while CO2, oxidized sulfur compounds, NO3- and O2 (only rarely) serve as electron acceptors. Growth demands of hyperthermophiles fit the scenario of a hot volcanism-dominated primitive Earth. Similar anaerobic chemolithoautotrophic hyperthermophiles, completely independent of a sun, could even exist on other planets provided that active volcanism and liquid water were present.","PeriodicalId":10218,"journal":{"name":"Ciba Foundation symposium","volume":"63 1","pages":"1-10; discussion 11-8"},"PeriodicalIF":0.0,"publicationDate":"2007-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91356319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-28DOI: 10.1002/9780470514634.CH11
S. Jain
Vast ethnobotanical knowledge exists in India from ancient time. Since the 1950s the study of ethnobotany has intensified; 10 books and 300 papers have been published. Our work over four decades, both in the field and literary studies, has resulted in a dictionary of Indian folk-medicine and ethnobotany that includes 2532 plants. India has about 45,000 plant species; medicinal properties have been assigned to several thousand. About 2000 figure frequently in the literature; indigenous systems commonly employ 500. Despite early (4500-1500 BC) origins and a long history of usage, in the last two centuries Ayurveda has received little official support and hence less attention from good medical practitioners and researchers. Much work is now being done on the botany, pharmacognosy, chemistry, pharmacology and biotechnology of herbal drugs. The value of ethnomedicine has been realized; work is being done on psychoactive plants, household remedies and plants sold by street drug vendors. Statistical methods are being used to assess the credibility of claims. Some recent work in drug development relates to species of Commiphora (used as a hypolipidaemic agent), Picrorhiza (which is hepatoprotective), Bacopa (used as a brain tonic), Curcuma (antiinflammatory) and Asclepias (cardiotonic). A scrutiny of folk claims found 203 plants for evaluation. Less well known ethnomedicines have been identified that are used to treat intestinal, joint, liver and skin diseases.
{"title":"Ethnobotany and research on medicinal plants in India.","authors":"S. Jain","doi":"10.1002/9780470514634.CH11","DOIUrl":"https://doi.org/10.1002/9780470514634.CH11","url":null,"abstract":"Vast ethnobotanical knowledge exists in India from ancient time. Since the 1950s the study of ethnobotany has intensified; 10 books and 300 papers have been published. Our work over four decades, both in the field and literary studies, has resulted in a dictionary of Indian folk-medicine and ethnobotany that includes 2532 plants. India has about 45,000 plant species; medicinal properties have been assigned to several thousand. About 2000 figure frequently in the literature; indigenous systems commonly employ 500. Despite early (4500-1500 BC) origins and a long history of usage, in the last two centuries Ayurveda has received little official support and hence less attention from good medical practitioners and researchers. Much work is now being done on the botany, pharmacognosy, chemistry, pharmacology and biotechnology of herbal drugs. The value of ethnomedicine has been realized; work is being done on psychoactive plants, household remedies and plants sold by street drug vendors. Statistical methods are being used to assess the credibility of claims. Some recent work in drug development relates to species of Commiphora (used as a hypolipidaemic agent), Picrorhiza (which is hepatoprotective), Bacopa (used as a brain tonic), Curcuma (antiinflammatory) and Asclepias (cardiotonic). A scrutiny of folk claims found 203 plants for evaluation. Less well known ethnomedicines have been identified that are used to treat intestinal, joint, liver and skin diseases.","PeriodicalId":10218,"journal":{"name":"Ciba Foundation symposium","volume":"57 1","pages":"153-64; discussion 164-8"},"PeriodicalIF":0.0,"publicationDate":"2007-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87049795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-28DOI: 10.1002/9780470514474.CH7
G. Norton
Historical profiles can be used to portray past pathways of agricultural development, the factors that affected pest status and the responses made by farmers in the form of pest management. Understanding the key factors affecting these historical developments is thought to be crucial for identifying likely future scenarios and associated opportunities and constraints for improving pest management. Evidence for this view is provided by four case studies: brassica pests in the United Kingdom; tsetse fly and trypanosomiasis management in The Gambia; rice pest management in the Lop-Buri area of Thailand; and pest management in dryland cotton in north-east Australia.
{"title":"Agricultural development paths and pest management: a pragmatic view of sustainability.","authors":"G. Norton","doi":"10.1002/9780470514474.CH7","DOIUrl":"https://doi.org/10.1002/9780470514474.CH7","url":null,"abstract":"Historical profiles can be used to portray past pathways of agricultural development, the factors that affected pest status and the responses made by farmers in the form of pest management. Understanding the key factors affecting these historical developments is thought to be crucial for identifying likely future scenarios and associated opportunities and constraints for improving pest management. Evidence for this view is provided by four case studies: brassica pests in the United Kingdom; tsetse fly and trypanosomiasis management in The Gambia; rice pest management in the Lop-Buri area of Thailand; and pest management in dryland cotton in north-east Australia.","PeriodicalId":10218,"journal":{"name":"Ciba Foundation symposium","volume":"28 ","pages":"100-9; discussion 110-5"},"PeriodicalIF":0.0,"publicationDate":"2007-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72553090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-28DOI: 10.1002/9780470514368.CH6
P. Lowry
CRF is unusual in that it is synthesized and released from the placenta into the circulation in humans, reaching levels in the third trimester that would normally be expected in the hypothalamic portal system during stress. This rise is even more pronounced in pregnancy-induced hypertension and preterm labour. Paradoxically, there is no associated rise of either ACTH or cortisol. This lack of biological response and the stability of the peptide in human (but not rat) plasma in vitro initiated a search for the human CRF-binding plasma protein. This CRF-BP proved to have a molecular mass in the region of 40 kDa, and has been purified to homogeneity. It has an affinity constant in the nanomolar range and when mixed with appropriate amounts of CRF completely inhibits the ACTH-releasing activity of the peptide in vitro. With the cloning of the cDNA for CRF-BP, sufficient pure material has become available for the development of a radioimmunoassay. Although CRF-BP levels in pregnant women are normal in the second trimester, they begin to fall by week 35, reaching approximately 50% of normal values by term. The net effect of this would be an accelerated increase in free, potentially biologically active CRF.
{"title":"Corticotropin-releasing factor and its binding protein in human plasma.","authors":"P. Lowry","doi":"10.1002/9780470514368.CH6","DOIUrl":"https://doi.org/10.1002/9780470514368.CH6","url":null,"abstract":"CRF is unusual in that it is synthesized and released from the placenta into the circulation in humans, reaching levels in the third trimester that would normally be expected in the hypothalamic portal system during stress. This rise is even more pronounced in pregnancy-induced hypertension and preterm labour. Paradoxically, there is no associated rise of either ACTH or cortisol. This lack of biological response and the stability of the peptide in human (but not rat) plasma in vitro initiated a search for the human CRF-binding plasma protein. This CRF-BP proved to have a molecular mass in the region of 40 kDa, and has been purified to homogeneity. It has an affinity constant in the nanomolar range and when mixed with appropriate amounts of CRF completely inhibits the ACTH-releasing activity of the peptide in vitro. With the cloning of the cDNA for CRF-BP, sufficient pure material has become available for the development of a radioimmunoassay. Although CRF-BP levels in pregnant women are normal in the second trimester, they begin to fall by week 35, reaching approximately 50% of normal values by term. The net effect of this would be an accelerated increase in free, potentially biologically active CRF.","PeriodicalId":10218,"journal":{"name":"Ciba Foundation symposium","volume":"1 1","pages":"108-15; discussion 115-28"},"PeriodicalIF":0.0,"publicationDate":"2007-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89628346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-28DOI: 10.1002/9780470514771.CH18
B. Starcher, M. Conrad
Hairless (SKH-1) mice were mated with beige (C57BL/bb) mice to produce a hairless mouse deficient in neutrophil elastase (hhbb). These mice were exposed to 0.09 J UVB radiation for 5 months to see if neutrophil elastase was an important factor in the development of solar elastosis. Analysis of peritoneal neutrophils confirmed that the hhbb mouse was deficient in elastase, retaining only 10% of the activity of the normal littermates (hhHb). Skin myeloperoxidase activity was equally elevated in all the mice receiving UVB indicating a similar influx of inflammatory cells. The absolute breaking strength of the skin in both the hhBb and hhbb mice was not altered by UVB treatment over the 5 month exposure period. Elastin quantitated biochemically as desmosine, or visualized histologically, was increased following UVB exposure in the normal mice. In the elastase-deficient mice, however, the elastin fibres appeared to be unaffected by exposure to UVB radiation at this level. The results suggest that neutrophil elastase is an important mediator in the development of solar elastosis resulting from continued exposure to UVB.
{"title":"A role for neutrophil elastase in solar elastosis.","authors":"B. Starcher, M. Conrad","doi":"10.1002/9780470514771.CH18","DOIUrl":"https://doi.org/10.1002/9780470514771.CH18","url":null,"abstract":"Hairless (SKH-1) mice were mated with beige (C57BL/bb) mice to produce a hairless mouse deficient in neutrophil elastase (hhbb). These mice were exposed to 0.09 J UVB radiation for 5 months to see if neutrophil elastase was an important factor in the development of solar elastosis. Analysis of peritoneal neutrophils confirmed that the hhbb mouse was deficient in elastase, retaining only 10% of the activity of the normal littermates (hhHb). Skin myeloperoxidase activity was equally elevated in all the mice receiving UVB indicating a similar influx of inflammatory cells. The absolute breaking strength of the skin in both the hhBb and hhbb mice was not altered by UVB treatment over the 5 month exposure period. Elastin quantitated biochemically as desmosine, or visualized histologically, was increased following UVB exposure in the normal mice. In the elastase-deficient mice, however, the elastin fibres appeared to be unaffected by exposure to UVB radiation at this level. The results suggest that neutrophil elastase is an important mediator in the development of solar elastosis resulting from continued exposure to UVB.","PeriodicalId":10218,"journal":{"name":"Ciba Foundation symposium","volume":"77 1","pages":"338-46; discussion 346-7"},"PeriodicalIF":0.0,"publicationDate":"2007-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88558535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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