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Department of Anatomy, Gunma University School of Medicine, Maebashi, Japan.
Ciliogenesis in human oviduct epithelium was studied with transmission and scanning electron microscopes. Both centriolar and acentriolar pathways were involved in duplication of centrioles. The plasma membrane surrounding the base of new cilia invaginated toward the distal end of the basal body during formation of transitional fibers. Fibrous granules were involved in development of striated rootlets in addition to formation of centrioles. The tips of rootlets elongated in fibrils with a banding pattern different from that of usual rootlets; further the fibrils' tips were laterally connected to cell organelles (mostly mitochondria). Ciliogenic cells in early stages contained secretory granule-like vesicles, suggesting that ciliogenic cells are differentiated from secretory cells. The ordinary course of ciliogenesis was disturbed in some ciliogenic cells, resulting in formation of various ciliary abnormalities. Intracytoplasmic ciliated cysts, cilia within periciliary sheaths, and intracytoplasmic axonemes were formed due to disturbance of migration of duplicated centrioles. Swollen cilia and some compound cilia were developed during ciliary elongation.
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PLoS Biol. 2007 Jun ;5 (6):e149
17518519
Cit:16
Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, United States of America.
Centriole positioning is a key step in establishment and propagation of cell geometry, but the mechanism of this positioning is unknown. The ability of pre-existing centrioles to induce formation of new centrioles at a defined angle relative to themselves suggests they may have the capacity to transmit spatial information to their daughters. Using three-dimensional computer-aided analysis of cell morphology in Chlamydomonas, we identify six genes required for centriole positioning relative to overall cell polarity, four of which have known sequences. We show that the distal portion of the centriole is critical for positioning, and that the centriole positions the nucleus rather than vice versa. We obtain evidence that the daughter centriole is unable to respond to normal positioning cues and relies on the mother for positional information. Our results represent a clear example of "cytotaxis" as defined by Sonneborn, and suggest that centrioles can play a key function in propagation of cellular geometry from one generation to the next. The genes documented here that are required for proper centriole positioning may represent a new class of ciliary disease genes, defects in which would be expected to cause disorganized ciliary position and impaired function.
Int Rev Cytol. 2004 ;234 :101-41
15066374
Cit:34
Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
Ciliogenesis is divided into four stages:(1) generation of centrioles,(2) migration of duplicated centrioles,(3) formation of the basal body-associated structures, and (4) elongation of cilia. The ultrastructural profile of ciliogenesis is fundamentally the same among various kinds of animal species. In acentriolar centriologenesis, centrioles are generated around deuterosomes by the use of fibrous granules. Components of the centriolar precursor structures, and genes that regulate the differentiation of ciliated cells, have been revealed. Ciliary abnormalities are classified into two categories: specific congenital defects of ciliary structure and acquired nonspecific anomalies of the ciliary apparatus. When ciliogenesis is disturbed, various nonspecific ciliary abnormalities develop in the cell. Inhibition of centriole migration results in the development of intracytoplasmic axonemes, cilia within periciliary sheaths, and intracellular ciliated vacuoles. Swollen cilia and the bulging type of compound cilia are formed during ciliary budding and elongation. Primary cilia can also develop from one of a pair of centrioles. They lack dynein arms and are immobile, but work as a mechanosensor and play a role during morphogenesis of the kidney. Abnormal function or structure of primary cilia results in the development of polycystic kidney disease. The axonemes of primary cilia or monocilia in the embryonic node cells are associated with dynein arms and move vortically. They have a role in determining the left-right (L-R) asymmetry of the fetus. This review also discusses the ciliogenesis of a primary cilium in the cell.
Institute for Anatomy and Physiology of Domestic Animals, University of Hohenheim, Fruwirthstrasse 35, 70599 Stuttgart, Germany.
The luminal epithelium of the porcine oviduct is composed of ciliated cells and secretory cells, but it is assumed for several species that under the control of steroid hormones secretory cells are able to be transformed into ciliated cells. In order to better understand such physiological changes during the different stages of the oestrous cycle, we evaluated epithelial cell proliferation together with oestrogen receptor alpha (ERalpha) expression of porcine ampullary oviducts. To identify the immunophenotype of proliferating cells, double immunohistochemistry was performed using anti-chromogranin A antibody (anti-CgA) as the second primary antibody. Anti-CgA, recently shown to be an immunocytochemical marker of ciliated cells of the cow, also labelled specifically the luminal surface of ciliated cells of the pig. Double labelling of sections with the monoclonal antibody MIB-1 against the proliferation-associated nuclear epitope Ki-67 and anti-CgA clearly demonstrates that MIB-1 was selectively localised in the nuclei of secretory cells. Proliferative activity was not observed in CgA-positive ciliated cells in all examined stages of the oestrous cycle. The percentage of Ki-67-positive epithelial cells was higher at pro-oestrus, compared with the other stages of the oestrous cycle. Furthermore, ERalpha immunoreactivity was exclusively detected in the nuclei of the epithelial cells, which were negative for CgA. We conclude, therefore, that oestrogen may induce the initial proliferation of secretory cells and promote the differentiation into ciliated cells.
Department of Anatomy and Cell Biology, Gunma University School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan. hhagiwar@med.gunma-u.ac.jp
Cilia are motile processes extending from the basal bodies, playing important roles in the mucociliary clearance in the respiratory tract and the transport of the ovum from the ovary to the uterus in mammals. Ciliogenesis is divided into four stages:(1) duplication of centrioles;(2) migration of centrioles to the apical cell surface to become basal bodies;(3) elongation of cilia containing the axoneme; and (4) formation of accessory structures of basal bodies. The orderly course of ciliogenesis appears to be disturbed by various internal and external factors and, as a result, various unusual forms of the ciliary apparatus develop in the cell. Inhibition of basal body migration results in development of intracytoplasmic axonemes, cilia within periciliary sheaths, and intracellular ciliated cysts. Swollen cilia and the bulging type of compound cilia are formed during ciliary budding and elongation. This review also discusses the origin, composition, and function of the centriolar precursor structures.
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Department of Thoracic and Cardiovascular Surgery, Kansai Rosai Hospital, Japan.
Graduate School of Science and Engineering, Advanced Information Science and Engineering Major, Human Information Science Course, Ritsumeikan University, 1-1-1 Noji Higashi, Kusatsu, Shiga 525-8577, Japan. ci004067@ed.ritsumei.ac.jp
A recently developed wearable device has gained attention in the area of self-discipline for the prevention of lifestyle-related diseases. The present study aimed to clarify the relationship between circadian rhythm and body shape change using actigraphy. Using a body shape vector, we classified 24 women in their 40s and 50s into 3 groups with different body shape changes. A circadian rhythm experiment was conducted on weekdays for 1 week with 24 healthy women. Amounts of activity of the non-dominant wrist and trunk, subjective evaluation of sleep quality, and subjective state of activity were surveyed. In order to maintain a constant body shape throughout life, a less sedentary lifestyle with more trunk movement during the day, getting adequate sleep at night, and having a varied sleep-wake cycle may be important factors.
J Comp Pathol. ;145 (2-3):122-5
21453928
Advanced Technology Development Center, Kyoritsu Seiyaku Corporation, Takamihara, Tsukuba, Ibaraki 300-1252, Japan.
An outbreak of disease in Seriola dumerili occurred from August to October in 2007 and 2008. The fish developed lesions of the caudal peduncle, pectoral and/or dorsal fin and the heart. The lesions were characterized by moderate to severe infarction with areas of microabscessation and multifocal granulomatous inflammation associated with the presence of Streptococcus dysgalactiae antigen. This is the first report to describe the immunohistology of the lesions induced in S. dumerili following natural infection with S. dysgalactiae.
Advanced Technology Development Center, Kyoritsu Seiyaku Corporation, Takamihara, Tsukuba, Ibaraki 300-1252, Japan. jerzy.kaleczyc@uwm.edu.pl
Seriola dumerili were infected experimentally with Streptococcus dysgalactiae by oral dosing or immersion. There was moderate mortality after immersion in water containing defined numbers of bacteria, regardless of the dose, whereas the effect on the oral challenge groups depended on the dose of bacteria administered. The characteristic lesions were microabscesses and/or pyogranulomatous inflammation of the caudal peduncle, pectoral and/or dorsal fin, heart and olfactory region. S. dysgalactiae antigen was found within necrotic foci at these sites. There was no difference in distribution of S. dysgalactiae antigen in fish that were exposed by oral or immersion challenge. There was no difference in antigen distribution when fish that died were compared with those that survived and were killed. Immersion exposure is therefore a more effective natural route of infection than oral challenge.
Kyobu Geka. 2009 Dec ;62 (13):1170-3
19999097
Department of Cardiovascular Surgery, Japanese Red Cross Nagoya First Hospital, Nagoya, Japan.
We report a case of surgical treatment for ascending aortic aneurysm and aortic valve regurgitation (AR) 24 years after operative repair of coarctation of the aorta (CoA). The patient was a 32-year-old man who had undergone operative repair of CoA and patent ductus arteriosus (PDA) ligation when 8 years old, and was followed since then. However, since 14 years after the operation, dilation of his ascending aorta and AR was observed. Then the AR deteriorated and the ascending aorta dilated, and at 24 years after operation he had symptoms of heart failure. So we performed ascending aorta replacement and aortic root replacement (reimplantation). Despite primary success of the operative repair of CoA, however. 9% of patients develop aortic aneurysms long after the operation. Therefore, long-term follow-up is needed after repair of coarctation of the aorta.
Y Inoue,
N Hiramatsu,
T Oze,
T Yakushijin,
K Mochizuki,
H Hagiwara,
M Oshita,
E Mita,
H Fukui,
M Inada,
S Tamura,
H Yoshihara,
E Hayashi,
A Inoue,
Y Imai,
M Kato,
T Miyagi,
A Hohsui,
H Ishida,
S Kiso,
T Kanto,
A Kasahara,
T Takehara,
N Hayashi
Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita City, Osaka, Japan.
Reducing the dose of drug affects treatment efficacy in pegylated interferon (Peg-IFN) and ribavirin combination therapy for patients with hepatitis C virus (HCV) genotype 1. The aim of this study was to investigate the impact of drug exposure, as well as the baseline factors and the virological response on the treatment efficacy for genotype 2 patients. Two-hundred and fifty patients with genotype 2 HCV who were to undergo combination therapy for 24 weeks were included in the study, and 213 completed the treatment. Significantly more patients who achieved a rapid virological response (RVR), defined as HCV RNA negativity at week 4, achieved a sustained virological response (SVR)(92%, 122/133) compared with patients who failed to achieve RVR (48%, 38/80)(P < 0.0001). Multivariate logistic-regression analysis showed that only platelet counts [odds ratio (OR), 1.68; confidence interval (CI), 1.002-1.139] and RVR (OR, 11.251; CI, 5.184-24.419) were independently associated with SVR, with no correlation being found for the mean dose of Peg-IFN and ribavirin for RVR and SVR. Furthermore, in the stratification analysis of the timing of viral clearance, neither mean dose of Peg-IFN (P = 0.795) nor ribavirin (P = 0.649) affected SVR in each group. Among the patients with RVR, the lowest dose group of Peg-IFN (0.77 +/- 0.10 microg/kg/week) and ribavirin (6.9 +/- 0.90 mg/kg/day) showed 100% and 94% of SVR. Hence, RVR served as an important treatment predictor, and drug exposure had no impact on both SVR and RVR in combination therapy for genotype 2 patients.
N Hiramatsu,
T Oze,
T Yakushijin,
Y Inoue,
T Igura,
K Mochizuki,
K Imanaka,
A Kaneko,
M Oshita,
H Hagiwara,
E Mita,
T Nagase,
T Ito,
Y Inui,
T Hijioka,
K Katayama,
S Tamura,
H Yoshihara,
Y Imai,
M Kato,
Y Yoshida,
T Tatsumi,
K Ohkawa,
S Kiso,
T Kanto,
A Kasahara,
T Takehara,
N Hayashi
Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Osaka 565-0871, Japan. hiramatsu@gh.med.osaka-u.ac.jp
The impact of ribavirin exposure on virologic relapse remains controversial in combination therapy with pegylated interferon (Peg-IFN) and ribavirin for patients with chronic hepatitis C (CH-C) genotype 1. The present study was conducted to investigate this. Nine hundred and eighty-four patients with CH-C genotype 1 were enrolled. The drug exposure of each medication was calculated by averaging the dose actually taken. For the 472 patients who were HCV RNA negative at week 24 and week 48, multivariate logistic regression analysis showed that the degree of fibrosis (P = 0.002), the timing of HCV RNA negativiation (P < 0.001) and the mean doses of ribavirin (P < 0.001) were significantly associated with relapse, but those of Peg-IFN were not. Stepwise reduction of the ribavirin dose was associated with a stepwise increase in relapse rate from 11% to 60%. For patients with complete early virologic response (c-EVR) defined as HCV RNA negativity at week 12, only 4% relapse was found in patients given > or = 12 mg/kg/day of ribavirin and ribavirin exposure affected the relapse even after treatment week 12, while Peg-IFN could be reduced to 0.6 microg/kg/week after week 12 without the increase of relapse rate. Ribavirin showed dose-dependent correlation with the relapse. Maintaining as high a ribavirin dose as possible (> or = 12 mg/kg/day) during the full treatment period can lead to suppression of the relapse in HCV genotype 1 patients responding to Peg-IFN alpha-2b plus ribavirin, especially in c-EVR patients.
T Oze,
N Hiramatsu,
T Yakushijin,
M Kurokawa,
T Igura,
K Mochizuki,
K Imanaka,
A Yamada,
M Oshita,
H Hagiwara,
E Mita,
T Ito,
Y Inui,
T Hijioka,
S Tamura,
H Yoshihara,
E Hayashi,
A Inoue,
Y Imai,
M Kato,
Y Yoshida,
T Tatsumi,
K Ohkawa,
S Kiso,
T Kanto,
A Kasahara,
T Takehara,
N Hayashi
Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Yamadaoka, Suita, Osaka 565-0871, Japan.
Chronic hepatitis C (CH-C) genotype 1 patients who achieved early virologic response have a high probability of sustained virologic response (SVR) following pegylated interferon (Peg-IFN) plus ribavirin therapy. This study was conducted to evaluate how reducing drug doses affects complete early virologic response (c-EVR) defined as hepatitis C virus (HCV) RNA negativity at week 12. Nine hundred eighty-four patients with CH-C genotype 1 were enrolled. Drug doses were evaluated independently on a body weight base from doses actually taken. From multivariate analysis, the mean dose of Peg-IFN alpha-2b during the first 12 weeks was the independent factor for c-EVR (P = 0.02), not ribavirin. The c-EVR rate was 55% in patients receiving > or = 1.2 microg/kg/week of Peg-IFN, and declined to 38% at 0.9-1.2 microg/kg/week, and 22% in patients given <0.9 microg/kg/week (P < 0.0001). Even with stratified analysis according to ribavirin dose, the dose-dependent effect of Peg-IFN on c-EVR was observed, and similar c-EVR rates were obtained if the dose categories of Peg-IFN were the same. Furthermore, the mean dose of Peg-IFN during the first 12 weeks affected HCV RNA negativity at week 24 (P < 0.0001) and SVR (P < 0.0001) in a dose-dependent manner. Our results suggest that Peg-IFN was dose-dependently correlated with c-EVR, independently of ribavirin dose. Thus, maintaining the Peg-IFN dose as high as possible during the first 12 weeks can yield HCV RNA negativity and higher c-EVR rates, leading to better SVR rates in patients with CH-C genotype 1.
Kyobu Geka. 2009 Mar ;62 (3):247-50
19280960
Department of Cardiovascular Surgery, Nagoya First Red Cross Hospital, Nagoya, Japan.
We report a 74-year-old man with aortoesophageal fistula due to aotic aneurysm. He underwent 2 stage operations. At the 1st operation the graft replacement of thoracic aorta and esophagectomy were performed. Inflammatory reactions improved with systemic administration of antibiotics and continuous irrigation of the thoracic cavity. On the 21st postoperative day, the esophagus was reconstructed by gastrointestinal interposition technique via ante-thoracic route. On the 58th post operative day he was discharged.
Kyobu Geka. 2009 Mar ;62 (3):219-22
19280954
Department of Cardiovascular Surgery, Japanese Red Cross Nagoya First Hospital, Nagoya, Japan.
The patient was a 53-year-old woman who complained of chest pain. Echocardiography and angiography revealed mild aortic regurgitation (AR) with an eccentric jet and an unruptured aneurysm of the non-coronary sinus of Valsalva which protruded into the left atrium. Operative findings showed that tethering due to elongation of the circumference of the aortic wall at the level of the non-coronary sinus commissures caused AR. Then patch closure and partial sino-tubular (ST) junction plication were carried out. Postoperative echocardiography showed decrease of AR and complete repair of the aneurysm of Valsalva sinus.
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Protoplasma. 2012 Apr 4;:
22476260
Graduate School of Environmental Science, Hokkaido University, Sapporo, 060-0810, Japan.
Flagellar development in the plurilocular zoidangia of sporophytes of the brown alga Ectocarpus siliculosus was analyzed in detail using transmission electron microscopy and electron tomography. A series of cell divisions in the plurilocular zoidangia produced the spore-mother cells. In these cells, the centrioles differentiated into flagellar basal bodies with basal plates at their distal ends and attached to the plasma membrane. The plasma membrane formed a depression (flagellar pocket) into where the flagella elongated and in which variously sized vesicles and cytoplasmic fragments accumulated. The anterior and posterior flagella started elongating simultaneously, and the vesicles and cytoplasmic fragments in the flagellar pocket fused to the flagellar membranes. The two flagella (anterior and posterior) could be clearly distinguished from each other at the initial stage of their development by differences in length, diameter and the appendage flagellar rootlets. Flagella continued to elongate in the flagellar pocket and maintained their mutually parallel arrangement as the flagellar pocket gradually changed position. In mature zoids, the basal part of the posterior flagellum (paraflagellar body) characteristically became swollen and faced the eyespot region. Electron dense materials accumulated between the axoneme and the flagellar membrane, and crystallized materials could also be observed in the swollen region. Before liberation of the zoospores from the plurilocular zoidangia, mastigoneme attachment was restricted to the distal region of the anterior flagellum. Structures just below the flagellar membrane that connected to the mastigonemes were clearly visible by electron tomography.
College of Life and Environment Science, Shanghai Normal University, Shanghai, China.
By using scanning and transmission electron microscopy, the present study demonstrates a great number of trichocyst-like extrusomes distributed in the cortical cytoplasm of the protozoan Pseudourostyla cristata, a hypotrichous ciliate. Of these, the mature organelles are rod-shaped with a cap consisting of tubular structures, a tip located at the apex of the cap, a body consisting of strateform structures of uneven electron density and an elongated shaft located along the longitudinal central axis of the body. The electron microscopic observations suggest that the extrusive organelles in P. cristata might undergo a morphogenetic process including the following sequential events: the occurrence of the vesicles in the cytoplasm, the condensation of the fibrous substances within the vesicles, the appearance of the electron-dense shaft, and the formation of the cap. In contrast with a large quantity of extrusomes in trophozoit P. cristata, there are no such extrusive organelles in the encysted cells of the ciliate. The phenomena that P. cristata ciliates can readily enter physiological reorganization or encysting phases and discharge a great number of their extrusomes when prepared for SEM and TEM observation suggest that the extrusive process of the extrusomes in P. cristata might have an important influence on the life activity of the ciliate and could be one of the causes leading to the physiological reorganization and the encysting of the ciliate. These reactions of P. cristata might be a protective or defensive response to the environmental changes.
Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan. hhagiwar@med.gunma-u.ac.jp
The human oviduct is lined with a simple columnar epithelium composed of ciliated cells and secretory cells. Primary cilia or solitary cilia usually extend from the apical surface of the secretory cells. The axoneme of the primary cilia is composed of nine peripheral microtubule doublets (9 + 0 pattern) that lack dynein arms and nexin links. Displacement of peripheral doublets to the central region, which is suggested to be attributable to the lack of nexin links, is one of the distinctive features of oviductal primary cilia. The basal body that extends the primary cilium connects to its paired centriole by the striated connector. The basal body is associated with the accessory structures, such as alar sheets, basal feet, and striated rootlets. Several basal feet project laterally from the basal body. The cap of the basal foot serves as the microtubule organizing center. Several striated rootlets radiate from the basal body toward the nucleus. The basal body, the paired centriole, and the basal body-associated structures are considered to play important roles in the stabilization and fixing of the cilium in the proper position on the apical cell surface.
Anat Histol Embryol. 2008 Sep 16;:
18798837
Cit:3
Lehrstuhl of Veterinary Anatomy II, University of Munich, Veterinärstrasse 13, D-80539 Munich, Germany.
In this study, we investigated the ultrastructural changes during the prenatal differentiation of oviductal epithelium in 16 bovine embryos and fetuses from CRL of 18.0 cm to a CRL of 94.0 cm. Ciliated and secretory cells of bovine uterine tube, a derivative of the Müllerian duct, differentiate to distinct development stages in the prenatal period. The typical cellular pattern, which is generally characteristic for the adult bovine oviduct, is also obtained during fetal life. In the early stages (CRL 18.0/20.4 cm), the bovine oviductal epithelium appears mostly undifferentiated. The epithelial cells show only a few mitochondria, some cisternae of rough endoplasmic reticulum (rER) and a small Golgi-complex. Most of the cytoplasm is filled with a large amount of glycogen, which decreases during later development. Interspersed between the undifferentiated epithelial cells, a few cells undergoing ciliogenesis can be observed. Ciliogenesis increased significantly during the later prenatal developmental stages. At a CRL of 55.0 cm, ciliated cells appear fully differentiated with mature cells covering their luminal surface. Formation of cilia usually use the acentriolar pathway. Fibrous granules occurred initially in association with the Golgi-apparatus and r(ER) in the supranuclear cytoplasm. Fibrous granules later fuse with deuterosomes and give rise to procentrioles, which are translocated to the luminal plasma membrane. There they become arranged in a line just beneath the apical cell membrane and further differentiate to basal bodies from which the formation of cilia and striated rootlets take place. Clear signs of differentiation of secretory cells were first seen in our material in fetuses with a CRL of 51.0 cm and 64.0 cm. These cells contain a well developed rER and Golgi-apparatus with dilated cisterns. In the supranuclear cytoplasm, the number of secretory granules continuously increases during later development and the cells adapt to the morphology of mature secretory cells at the CRL 94.0 cm.
Department of Genetics, Stanford University School of Medicine, Stanford University, Stanford, CA 94305, USA.
Ciliated epithelial cells have the unique ability to generate hundreds of centrioles during differentiation. We used centrosomal proteins as molecular markers in cultured mouse tracheal epithelial cells to understand this process. Most centrosomal proteins were up-regulated early in ciliogenesis, initially appearing in cytoplasmic foci and then incorporated into centrioles. Three candidate proteins were further characterized. The centrosomal component SAS-6 localized to basal bodies and the proximal region of the ciliary axoneme, and depletion of SAS-6 prevented centriole assembly. The intraflagellar transport component polaris localized to nascent centrioles before incorporation into cilia, and depletion of polaris blocked axoneme formation. The centriolar satellite component PCM-1 colocalized with centrosomal components in cytoplasmic granules surrounding nascent centrioles. Interfering with PCM-1 reduced the amount of centrosomal proteins at basal bodies but did not prevent centriole assembly. This system will help determine the mechanism of centriole formation in mammalian cells and how the limitation on centriole duplication is overcome in ciliated epithelial cells.
Ontogenez. ;36 (3):190-8
15977801
An electron microscopic study of the ciliary epithelium of respiratory tracts was carried out in children (members of the same family) with Kartagener syndrome, which is a variant of ciliary dyskinesia. It was shown that in the case of both mobile cilia and ciliary dyskinesia in man, centrioles are formed during formation of the ciliary basal bodies predominantly de novo, involving deuterosomes. A wide spectrum of pathological changes was described in literature, such as the absence of dynein arms in the axoneme and disorganization of axoneme structure. In addition to these changes in the ciliary system, we found integration of several ciliary axonemes by the same plasma membrane, running of microtubules from the plasma membrane as bundles, different orientation of basal legs, etc.
Int Rev Cytol. 2004 ;234 :101-41
15066374
Cit:34
Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
Ciliogenesis is divided into four stages:(1) generation of centrioles,(2) migration of duplicated centrioles,(3) formation of the basal body-associated structures, and (4) elongation of cilia. The ultrastructural profile of ciliogenesis is fundamentally the same among various kinds of animal species. In acentriolar centriologenesis, centrioles are generated around deuterosomes by the use of fibrous granules. Components of the centriolar precursor structures, and genes that regulate the differentiation of ciliated cells, have been revealed. Ciliary abnormalities are classified into two categories: specific congenital defects of ciliary structure and acquired nonspecific anomalies of the ciliary apparatus. When ciliogenesis is disturbed, various nonspecific ciliary abnormalities develop in the cell. Inhibition of centriole migration results in the development of intracytoplasmic axonemes, cilia within periciliary sheaths, and intracellular ciliated vacuoles. Swollen cilia and the bulging type of compound cilia are formed during ciliary budding and elongation. Primary cilia can also develop from one of a pair of centrioles. They lack dynein arms and are immobile, but work as a mechanosensor and play a role during morphogenesis of the kidney. Abnormal function or structure of primary cilia results in the development of polycystic kidney disease. The axonemes of primary cilia or monocilia in the embryonic node cells are associated with dynein arms and move vortically. They have a role in determining the left-right (L-R) asymmetry of the fetus. This review also discusses the ciliogenesis of a primary cilium in the cell.
Ontogenez. ;33 (3):187-94
12068719
Moscow State University, Vorob'evy gory, Moscow, 119899 Russia.
Electron microscopic studies of the leg ciliary epithelium was carried out in two mollusks. In the epithelium of the leg of adult animals, the centrioles were mostly formed de novo with participation of deuterosomes during the formation of basal bodies. Transformation of the centriolar cylinder in a mature basal body is accompanied by the cylinder elongation and appearance of pericentriolar structures, such as rootlet system, basal legs, and basal plate. Centriolegenesis proceeds in both ciliate and nonciliate (with microvilli) cells of the epithelium. It has been proposed that the cell with microvilli represent a transitional stage in differentiation of the ciliary cells.
J Anat. 2002 Jan ;200 (Pt 1):89-96
11833657
Cit:8
Department of Anatomy and Cell Biology, Gunma University School of Medicine, Maebashi, Japan. hhagiwar@med.gunma-u.ac.jp
The basal apparatus of the solitary cilium is composed of the basal body, an associated centriole and the basal body-associated structures. To see the connection between the basal body and the centriole, we studied the basal apparatus of solitary cilia in human oviductal secretory cells by electron microscopy and immunohistochemistry. A single centriole was present in the vicinity of the basal body of a solitary cilium. The basal body and the single centriole were interconnected by one or two bundles of thin filaments with a few periodic striations. We have called these bundles the striated connector. The periodicity of striations in the striated connector measured 55 +/- 6 nm, about 15 nm shorter than that of striated rootlets. The striated connector was immunolabelled with R67 antibody specific to striated rootlets, indicating that they are composed of common molecule(s). Although the true function of the connector is unknown as yet, it could play an important role for stabilising the basal body in the apical cytoplasm.
Department of Anatomy and Cell Biology, Gunma University School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan. hhagiwar@med.gunma-u.ac.jp
Cilia are motile processes extending from the basal bodies, playing important roles in the mucociliary clearance in the respiratory tract and the transport of the ovum from the ovary to the uterus in mammals. Ciliogenesis is divided into four stages:(1) duplication of centrioles;(2) migration of centrioles to the apical cell surface to become basal bodies;(3) elongation of cilia containing the axoneme; and (4) formation of accessory structures of basal bodies. The orderly course of ciliogenesis appears to be disturbed by various internal and external factors and, as a result, various unusual forms of the ciliary apparatus develop in the cell. Inhibition of basal body migration results in development of intracytoplasmic axonemes, cilia within periciliary sheaths, and intracellular ciliated cysts. Swollen cilia and the bulging type of compound cilia are formed during ciliary budding and elongation. This review also discusses the origin, composition, and function of the centriolar precursor structures.
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