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Morphometric changes associated with sex and development in the Malpighian tubules of Aedes aegypti. 埃及伊蚊马尔比氏小管中与性别和发育相关的形态计量学变化。
Cytobios Pub Date : 2000-01-01
R C de Sousa, H E Bicudo
{"title":"Morphometric changes associated with sex and development in the Malpighian tubules of Aedes aegypti.","authors":"R C de Sousa,&nbsp;H E Bicudo","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The Malpighian tubules of Aedes aegypti showed significant differences in their diameters between male and female larvae, male and female pupae, male larvae and male adults and male pupae and male adults. In every case, female values were greater than in males. Measurements of mean nuclear areas of the principal and stellate cells from Malpighian tubules, taken in males and females during development, showed that this parameter in both types of cell was significantly greater in females than in male larvae, pupae and adult stages. In males, significant differences between developmental stages were observed only in comparison with the nuclear area of larvae and adults in the principal cells, but in females, every comparison between stages showed significant differences except between pupae and adults in stellate cells. The frequency distribution of nuclear area values, in development, for male stellate and principal cells, were mostly concentrated in the first seven classes among the 30 classes considered in every stage, while for females, the frequency dropped drastically in the same classes from larvae to pupae and adults, moving to classes of higher values. Considering the importance of Malpighian tubules in insect physiology, the meaning of the differences detected are discussed on the basis of different metabolic levels, between sexes and developmental stages.</p>","PeriodicalId":11078,"journal":{"name":"Cytobios","volume":"102 401","pages":"173-86"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21806274","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}
引用次数: 0
Thamnocephalis quadrupedata (Mucorales) as a mycoparasite of the entomophthoraceous fungus Basidiobolus ranarum. 四足Thamnocephalis四足Thamnocephalis四足Thamnocephalis四足Thamnocephalis四足Thamnocephalis四足Thamnocephalis四足Thamnocephalis四足Thamnocephalis四足Thamnocephalis
Cytobios Pub Date : 2000-01-01
C Y Chien
{"title":"Thamnocephalis quadrupedata (Mucorales) as a mycoparasite of the entomophthoraceous fungus Basidiobolus ranarum.","authors":"C Y Chien","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A mycoparasite identified as Thamnocephalis quadrupedata (Mucorales) was observed on cultures of the frog dung fungus, Basidiobolus ranarum. The parasitic fungus, T. quadrupedata possessed infection hyphae with appressoria and penetrating hyphae to attack their host prey and adhere firmly to the surface. The invasion was often by slender infection hyphae or infecting pegs which grew from the appressoria and penetrated the chitin-protein cuticle by both mechanical pressure and exocellular enzymes. The host fungus, B. ranarum, possessing primary conidia, capilliconidia, hyphal bodies, vegetative mycelia and zygospores, were infected by means of direct penetration and intrahyphal growth, resulting in host cell death. T. quadrupedata may also grow as a saprophyte on damp filter paper in a Petri dish, manifesting facultative necrosis.</p>","PeriodicalId":11078,"journal":{"name":"Cytobios","volume":"103 403","pages":"71-8"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21902996","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}
引用次数: 0
Alterations in some membrane properties in rat brain following exposure to lead. 暴露于铅后大鼠脑某些膜特性的改变。
Cytobios Pub Date : 2000-01-01
G J Flora, P K Seth
{"title":"Alterations in some membrane properties in rat brain following exposure to lead.","authors":"G J Flora,&nbsp;P K Seth","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The effect of lead exposure on intracellular calcium levels, membrane fluidity, lipid peroxidation, acetylcholinesterase and monoamine oxidase activity and its accumulation in different regions of the brain were studied to understand the molecular mechanism of lead induced neurotoxicity. Lead treatment (20 mg/kg lead nitrate, intraperitoneally, once daily for 15 days) resulted in a significant accumulation of lead in all brain regions with the maximum being in the hippocampus. Levels of glutathione, lipid peroxidation, intracellular calcium and membrane fluidity, as well as the activity of the membrane bound enzymes, acetylcholinesterase and monoamine oxidase, increased to a significant level in certain areas of the rat brain. The results suggest that lead exerts neurotoxic effects by altering certain membrane bound enzymes and may cause oxidative stress.</p>","PeriodicalId":11078,"journal":{"name":"Cytobios","volume":"103 403","pages":"103-9"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21903000","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}
引用次数: 0
Some oncogene and tumour suppressor gene protein products expression in B-cell chronic lymphocytic leukaemia. 某些癌基因和肿瘤抑制基因蛋白产物在b细胞慢性淋巴细胞白血病中的表达。
Cytobios Pub Date : 2000-01-01
H Niewiadomska, M Mirowski, D Kulczycka, M Najder, E Balcerczak, J Z Błoński
{"title":"Some oncogene and tumour suppressor gene protein products expression in B-cell chronic lymphocytic leukaemia.","authors":"H Niewiadomska,&nbsp;M Mirowski,&nbsp;D Kulczycka,&nbsp;M Najder,&nbsp;E Balcerczak,&nbsp;J Z Błoński","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The expression of Bcl-2, P53 proteins and known markers of proliferation, namely proliferating cell nuclear antigen (PCNA) and Ki67, in 29 patients with B-cell chronic lymphocytic leukaemia (B-CLL) was investigated. All leukaemic patients were classified, and immunophenotyped by the two-colour immunofluorescence method with the use of fluorocytometry. B-CLL was heterogeneous in the range of biological parameters of tumour cells. B-CLL patients manifested 34% positive Ki67 and 61% PCNA expression, whereas Bcl-2 and P53 positivity was 81% and 42%, respectively. The level of intracellular expression of Bcl-2 and P53 proteins did not depend on the stage of disease estimated by routine methods. Ki67 and PCNA expression was significantly higher in B-CLL patients with more advanced stages of the disease. A statistically significant correlation was established between their mutual expression.</p>","PeriodicalId":11078,"journal":{"name":"Cytobios","volume":"103 404","pages":"159-68"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21911725","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}
引用次数: 0
Effect of chronic excess of tumour necrosis factor-alpha on contractile proteins in rat skeletal muscle. 肿瘤坏死因子- α慢性过量对大鼠骨骼肌收缩蛋白的影响。
Cytobios Pub Date : 2000-01-01
I R Cheema, C Hermann, S Postell, P Barnes
{"title":"Effect of chronic excess of tumour necrosis factor-alpha on contractile proteins in rat skeletal muscle.","authors":"I R Cheema,&nbsp;C Hermann,&nbsp;S Postell,&nbsp;P Barnes","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The effect of chronic tumour necrosis factor-alpha (TNF-alpha) treatment on the synthesis of specific myofibrillar proteins such as heavy chain myosin, light chain myosin and G-actin in rat diaphragm were evaluated. Muscles (diaphragm) from control and experimental groups (TNF-alpha i.v. at 50 microg/kg body wt for 5 days) were incubated in the presence of 35S-methionine for 2 h. Myofibrillar protein extracts were prepared and protein was electrophoresed on sodium dodecyl sulphate-polyacrylamide gels. Heavy chain myosin, light chain myosin and G-actin were identified by Western blot analysis using specific monoclonal antibodies. Polyacrylamide gel electrophoresis (PAGE) followed by Western blot analysis revealed two types of heavy chain myosin (206 and 212 kD), all four types of light chain myosin (15, 16.5, 18 and 20 kD) and a single type of G-actin (42 kD). Chronic TNF-alpha treatment produced a significant decline in the synthesis of all types of myofibrillar proteins, namely heavy chain myosin, light chain myosin and G-actin. TNF-alpha impaired peptide-chain initiation in diaphragm muscle which was reversed by the branched-chain amino acids (BCAA) therapy of TNF-alpha treated rats. These findings indicate a significant role for TNF-alpha in the translational regulation of protein synthesis in skeletal muscle.</p>","PeriodicalId":11078,"journal":{"name":"Cytobios","volume":"103 404","pages":"169-76"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21911726","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}
引用次数: 0
Chromosome evolution involving Robertsonian rearrangements in Xyrichthys fish (Labridae, Perciformes). 包含Robertsonian重排的Xyrichthys鱼的染色体进化(唇形科)。
Cytobios Pub Date : 2000-01-01
K Ueno, A Takai
{"title":"Chromosome evolution involving Robertsonian rearrangements in Xyrichthys fish (Labridae, Perciformes).","authors":"K Ueno,&nbsp;A Takai","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Three Xyrichthys fish (Labridae, Perciformes), X. pavo, X. dea, and X. twistii, were cytogenetically studied. X. pavo and X. dea had 2n = 44 chromosomes, which were all acrocentric. X. twistii had 2n = 22 chromosomes consisting of eighteen meta- and submetacentric and four acrocentric chromosomes. The cellular DNA contents of X. pavo and X. twistii measured using flow cytometry were nearly equal. These results suggest that the karyotype of X. twistii evolved by decreasing the number of chromosomes by fusion events, probably Robertsonian fusion. Cytogenetic relationships among the three species were surmized on the basis of features on the karyotypes and the NOR locations. A large gap in the chromosome number between 2n = 44 and 2n = 22 is an interesting feature related to the process of chromosome evolution.</p>","PeriodicalId":11078,"journal":{"name":"Cytobios","volume":"103 402","pages":"7-15"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21862264","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}
引用次数: 0
The sequestration of hydroxyl ions by CO2 in liquid water: the physiological implications and the second function of carbonic anhydrase. 液态水中CO2对羟基离子的固存:碳酸酐酶的生理意义和第二功能。
Cytobios Pub Date : 2000-01-01
W F Widdas, G F Baker
{"title":"The sequestration of hydroxyl ions by CO2 in liquid water: the physiological implications and the second function of carbonic anhydrase.","authors":"W F Widdas,&nbsp;G F Baker","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The pH changes due to bubbling CO2 through water produced anomalies which were more readily explained by an hypothesis based on electrostatic attractions between the molecules. The present studies have suggested that an hexagonal array of six carbon dioxide molecules could bind and sequester a hydroxyl anion. The binding energy of the complex is estimated to be comparable with that of a covalent compound and its dissociation may only occur at the water interface with air or at the water/hydrophobic protein interface in a protein cleft. The physiological importance lies in the consequential release of an equal number of free hydrogen ions (H3O+) and the disruption of the normal action of buffer systems in regulating the cytoplasmic pH. The counteraction of this sequestration reaction and the acid-base disturbances which result, form the second important function of carbonic anhydrase isoforms, the mechanisms of which are briefly discussed.</p>","PeriodicalId":11078,"journal":{"name":"Cytobios","volume":"103 402","pages":"39-60"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21862267","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}
引用次数: 0
Extracellular matrix effects on a neuroblastoma cell line. 细胞外基质对神经母细胞瘤细胞系的影响。
Cytobios Pub Date : 2000-01-01
M Hahn, T Glass, J Koke
{"title":"Extracellular matrix effects on a neuroblastoma cell line.","authors":"M Hahn,&nbsp;T Glass,&nbsp;J Koke","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Cells of various lines assume similar shapes when grown attached to substrates like coverslips. In contrast, cells cultured in a collagen and/or laminin matrix often assume a relatively normal morphology in comparison with their in situ counterparts. During investigations of neuroblastoma SH-SY5Y cells, an attempt was made to identify culture conditions which would cause the cells to assume a more regular shape. SH-SY5Y cells cultured on bare coverslips, on coverslips coated with rat-tail collagen, and in approximately 1 mm thick gels containing extracellular matrix components were compared. Striking differences were apparent when comparing the gel-cultured cells with cells cultured on coverslips. Cells grown in the gel formed ganglia-like clusters which generated bundles of neurites which targeted other 'ganglia'. The same cells grown on coverslips, whether or not they were collagen-coated, appeared unaware of the presence of other cells, and did not cluster, nor did they generate neurites.</p>","PeriodicalId":11078,"journal":{"name":"Cytobios","volume":"102 399","pages":"7-19"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21667782","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}
引用次数: 0
DNA degradation in the kidney of folic acid-treated guinea pigs. 叶酸处理豚鼠肾脏的DNA降解。
Cytobios Pub Date : 2000-01-01
P M Zeis, M Tzaki, L Nakopoulou, P Nicolaidou, E Kavazarakis, A Messaritaki, M Moustaki, M P Zeis, D Gourgiotis
{"title":"DNA degradation in the kidney of folic acid-treated guinea pigs.","authors":"P M Zeis,&nbsp;M Tzaki,&nbsp;L Nakopoulou,&nbsp;P Nicolaidou,&nbsp;E Kavazarakis,&nbsp;A Messaritaki,&nbsp;M Moustaki,&nbsp;M P Zeis,&nbsp;D Gourgiotis","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Previous investigators agree on the increased DNA synthesis and destruction of tissues caused by folic acid (FA) administered parenterally. This study aims to clarify whether DNA degradation due to the destruction of cells and nuclei precedes DNA synthesis following FA administration. Forty guinea pigs were divided into four groups: group 1, contained 10 controls; in group 2, ten animals received intraperitoneally 300 mg/kg of body wt FA; in group 3, ten animals received FA and 12 h later frusemide intramuscularly in a dose of 7 mg/kg body wt; and finally in group 4, ten animals received frusemide as in group 3. FA produced necrosis of the epithelial cells of the convoluted tubules as the detection of the beta-aminoisobutyric acid end product of DNA and thymine catabolism indicated. Frusemide administered in group 3 had a favourable effect on the acute renal failure induced by FA.</p>","PeriodicalId":11078,"journal":{"name":"Cytobios","volume":"102 400","pages":"107-13"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21728157","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}
引用次数: 0
Nature and distribution of constitutive heterochromatin and NOR location in the grasshopper Phaeoparia megacephala (Romaleidae: Orthoptera). 巨头蚱蜢组成异染色质的性质、分布和NOR的位置。
Cytobios Pub Date : 2000-01-01
L G Pereira, M J de Souza
{"title":"Nature and distribution of constitutive heterochromatin and NOR location in the grasshopper Phaeoparia megacephala (Romaleidae: Orthoptera).","authors":"L G Pereira,&nbsp;M J de Souza","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The constitutive heterochromatin (CH) of Phaeoparia megacephala was studied using C-banding and fluorochrome staining (CMA3, DAPI and acridine orange). The nucleolar organizer regions (NOR) were identified with silver staining. The chromosome complement of this species was 2n = 23, XO in males, and 2n = 24, XX in females. The CH was pericentromeric in all chromosomes. L1, L2, L3 and X chromosomes showed large blocks of CH, while the medium and small chromosomes had small blocks. The staining procedure with acridine orange revealed the same pattern. All the pericentromeric regions showed small blocks of CMA3-positive constitutive heterochromatin (GC-rich regions), while only part of the large C-band positive chromosome segments (L1, L2, L3 and X) were CMA3 positive. This character demonstrates an uncommon heterogeneity of constitutive heterochromatin in P. megacephala. The fluorochrome DAPI did not reveal DAPI-positive regions (AT-rich regions). Silver staining revealed only one pair of medium chromosomes with NOR.</p>","PeriodicalId":11078,"journal":{"name":"Cytobios","volume":"103 403","pages":"111-9"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21902998","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}
引用次数: 0
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