The prognostic value of 18F-FDG PET/CT taken immediately after completion of radiotherapy for lung cancer treated with concurrent chemoradiotherapy: A pilot study.

PURPOSE: The prognostic value of F-18 fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) taken immediately after completion of radiotherapy in lung cancer patients is not well known. The purpose of this study is to assess the prognostic value of PET/CT taken immediately after completion of radiotherapy in lung cancer patients. MATERIALS AND METHODS: Patients with primary lung cancer planned to undergo concurrent chemoradiotherapy were enrolled. Patients underwent PET/CT scans at 3 time points: before radiotherapy, within 24hours of completing radiotherapy (im-PET/CT), and 2-9 months after radiotherapy (post-PET/CT). Maximum standardized uptake value (SUVmax) was obtained. A post-PET/CT-SUVmax cut-off of 2.5 was determined as radiotherapy success. RESULTS: Nineteen patients were enrolled. im-PET/CT-SUVmax for patients in the high post-PET/CT-SUVmax group was significantly higher than that of the low group (P=0.004). Receiver operator curve analysis indicated that im-PET/CT-SUVmax of 4.35 was an optimal cut-off value to discriminate between the two groups. Multivariable analysis showed that a high im-PET/CT-SUVmax was significantly associated with a high post-PET/CT-SUVmax (P=0.003). CONCLUSION: PET/CT-SUVmax taken immediately following radiotherapy was associated with that evaluated 2-9 months after radiotherapy.

Generation of ozone during irradiation using medical linear accelerators: an experimental study.

BACKGROUND: Some patients have noted a foul odor during radiation therapy sessions, but the cause of the odor remains unknown. Since we suspected that this phenomenon is due to ozone generated by ionizing radiation, this experimental study measured ozone concentrations in the treatment room and in a coiled polyvinyl chloride (PVC) tube placed within the radiation field. METHODS: We measured ozone concentrations using an ultraviolet absorption method and an ozone monitor. A PVC tube (inner diameter 7 mm, outer diameter 10 mm) was used to mimic the environment of the nasal cavity. The tube (790 cm) was coiled and set between two 4-cm-thick (for X-rays) or 2-cm-thick (for electron beams) water-equivalent solid phantoms. The sampling tube of the ozone monitor was inserted into the PVC tube, and the joint was sealed to prevent environmental air contamination. To measure ozone concentrations in the atmosphere, the sampling tube supplied with the unit was used. A linac was used on a full-sized treatment field (40 cm × 40 cm at a source-to-axis distance of 100 cm). The effect of an electron beam on ozone concentrations was also evaluated with a full-sized treatment field (40 cm × 40 cm at a source-to-surface distance of 100 cm). RESULTS: Ozone levels in the treatment room were undetectable before the start of daily treatment but reached 0.008 parts per million (ppm) or more at 1 h after the start of treatment. Concentrations then remained nearly constant at 0.010-0.015 ppm throughout the day. The maximum ozone concentration in the PVC tube was only 0.006 ppm, even when it was irradiated at 2400 monitor units/min. Depending on the X-ray dose rate, the concentration increased to a maximum of 0.010 ppm with oxygen flowing into the other end of the tube at 1.5 L/min. Ozone concentrations in the PVC tube did not differ significantly between X-ray and electron-beam irradiation. CONCLUSIONS: Only traces of ozone were found in the PVC tube that was used to mimic the nasal passages during radiation, these concentrations were too low for human perception. However, ozone concentrations did reach potentially detectable levels in the treatment room.

Unusual visual and olfactory perceptions during radiotherapy sessions: an investigation of the organs responsible.

During radiotherapy sessions to treat brain tumors or head-and-neck cancers, some patients experience unusual visual and/or olfactory perceptions. This prospective study sought to answer two questions: (i) what proportion of patients experience these unpleasant sensations?, and (ii) which organs are responsible? Eligible patients had brain or near-orbital tumors treated by helical tomotherapy. All were aged 10 years or older, able to communicate, and interviewed by a radiation oncologist at least once weekly during radiation therapy. If they had experienced such sensations, they were encouraged to join the second phase of the study. The patients were asked to indicate, using a button, when a sensation commenced and ended. The recorded data were collated with the treatment log. Thirty-eight consecutive patients were eligible. Twenty-six experienced visual and 13 olfactory sensations. The radiation doses to the organs related to the visual or olfactory sensations did not differ between patients who reported sensations and those who did not. Seventeen patients were enrolled in the second phase of the study. All 14 with visual sensations reported that the sensations occurred when the X-rays passed at eye level. Olfactory sensations were reported by eight out of nine patients when the X-rays passed through the olfactory epithelium and/or ethmoid sinus level. In conclusion, 68% of patients experienced visual sensations caused by X-rays passing through the level of the eyes, and 34% complained of olfactory sensations. With the exception of one patient, olfactory sensations occurred when the X-rays passed through the levels of the olfactory epithelium and/or ethmoid sinus.

Evaluation of 3-week-old layer chicks intratracheally challenged with Salmonella isolates from serogroup c1 (O:6,7) and Salmonella Enteritidis.

With the exception to Salmonella enterica serotype Typhimurium and S. Enteritidis (serogroups B [O:4] and D [O:9], respectively), there have been very few studies conducted on the respiratory tract as route of infection in chickens with salmonellas from serogroup C1 (O:6,7). Therefore, the purpose of this present study was to determine the potential organ invasion by Salmonella enterica serotype Potsdam (SP), S. Mbandaka (SM), and S. Infantis (SI) from serogroup C1 (O:6,7) and compare their characteristics with those of S. Enteritidis (SE) on intratracheally (IT) challenged 3-week-old layer chicks. A total of 360 one-day-old White Leghorn layer chicks were acquired from a commercial hatchery and randomly assigned into four treatment groups (SP, SM, SI, and SE, respectively), consisting of three independent trials. Chicks were grown up to 21 days (3 weeks) and IT-challenged thereafter with 106 CFU of respective salmonella organisms per group (n = 30). Chicks (n = 5) were humanely sacrificed every 24 h for 6 days post-IT infection and organs such as lung, heart, liver, spleen, kidney and caecal content were cultured for salmonella. All treatment groups exhibited colonization of lungs and caecal contents at 1 d (P = 0.475) and 4 d (P = 0.696) post-IT infection, respectively. There was no isolation of SP, SM, and SI in heart, liver, spleen, and kidney. In contrast, SE was obtained from heart, liver, and spleen of IT-infected chicks. The findings of this study contribute to a better understanding of the importance of the respiratory route in salmonella infection in poultry.

Characterization of Ornithobacterium rhinotracheale from commercial layer chickens in eastern Japan.

From a total of 72 commercial layer and pullet farms that were monitored in the eastern Japan area, 4 farms had mild to severe respiratory disease accompanied by decreased feed intake and drop in egg production. Microbiological analysis showed that 3 of the 4 farms, particularly from Fukushima, Tochigi, and Ibaraki prefectures, were positive for Ornithobacterum rhinotracheale (ORT). Out of 65 birds examined, ORT was isolated in 21 birds (32.31%). All isolates were Gram-negative pleomorphic rods with a colony size of 0.05 mm, translucent with grayish coloration, and with butyric smell after 48 h of incubation in 10% chicken blood agar at 37°C under microaerophilic conditions. All isolates reacted positively in the p-nitrophenyl-ß-d-galactopyranoside test within 3 h and were positive in cytochrome oxidase tests with an API 20NE identification system biocode of 0-0-2-0-0-0-4. An agar gel precipitation test showed that all isolates were serotype-A. All strains were positive in PCR by yielding a 784 bp amplicon of the 16S rRNA gene. All strains were resistant to amikacin, colistin, gentamicin, kanamycin, neomycin, polymyxin b, streptomycin, and sulfamethoxazole trimethoprim and susceptible to amoxicillin clavulanic acid, ampicillin, doxycycline, spectinomycin, and tetracycline. This study is the first characterization of ORT from commercial layer chickens in eastern Japan.

Wireless EEG patch sensor on forehead using on-demand stretchable electrode sheet and electrode-tissue impedance scanner.

A wireless electroencephalogram (EEG) sensor using a stretchable electrode sheet and electrode-tissue impedance measurement module is presented herein. The sensor can be attached to the forehead using biocompatible gel with the electrode sheet. The sensor is compactly designed for 3 cm × 9 cm × 6 mm with weight of 12 g. Impedance scanning circuit is also proposed to evaluate the skin surface condition before EEG measurements. We developed the impedance scanning board for 3 cm × 5 cm × 3 mm, with weight of 5.6 g. Results show that the proposed system demonstrates a promising performance in diagnosing the Alzheimer's disease using frequency domain analysis.

The detection of toxigenic Corynebacterium ulcerans from cats with nasal inflammation in Japan.

Corynebacterium ulcerans (toxigenic C. ulcerans) produces the diphtheria toxin, which causes pharyngeal and cutaneous diphtheria-like disease in people, and this bacterium is commonly detected in dogs and cats that are reared at home. It is considered dangerous when a carrier animal becomes the source of infection in people. To investigate the carrier situation of toxigenic C. ulcerans of cats bred in Japan, bacteria were isolated from 37 cats with a primary complaint of rhinitis in 16 veterinary hospitals in Osaka. Toxigenic C. ulcerans was detected in two of the cats. By drug sensitivity testing, the detected bacterium was sensitive to all investigated drugs, except clindamycin. It appears necessary to create awareness regarding toxigenic C. ulcerans infection in pet owners because this bacterium is believed to be the causative organism for rhinitis in cats.

Identification of novel tumour-associated antigens in canine mammary gland tumour.

UNLABELLED: Canine mammary gland tumour (MGT) is the most common neoplasm in female dogs and has similar biological characteristics to human MGT. Spontaneous canine MGT is a more attractive clinical model in oncological research than that of the murine experimental model. Tumour-associated antigens (TAAs), which are produced in tumour cells, are applied as tumour markers, tumour vaccine antigens and molecular targets of therapeutic drugs. In this study, we have primarily identified 13 different TAAs of canine MGT by serological immunoscreening of cDNA expression library. The results of serological mini-arrays of identified antigens showed that CCDC41 antigen specially reacted with 35% of sera from MGT-dogs and did not react with control sera. We also found that HSPH1 mRNA expression levels increased significantly in MGT tissues. These findings will contribute to the development of diagnostic technologies and translational target therapies for dogs. CLINICAL RELEVANCE: HSPH1, which is strongly expressed in the tumour tissue, will be a possible vaccine antigen of canine MGT.

Design study of electron cyclotron resonance-ion plasma accelerator for heavy ion cancer therapy.

Electron Cyclotron Resonance-Ion Plasma Accelerator (ECR-IPAC) device, which theoretically can accelerate multiple charged ions to several hundred MeV with short acceleration length, has been proposed. The acceleration mechanism is based on the combination of two physical principles, plasma electron ion adiabatic ejection (PLEIADE) and Gyromagnetic Autoresonance (GYRAC). In this study, we have designed the proof of principle machine ECR-IPAC device and simulated the electromagnetic field distribution generating in the resonance cavity. ECR-IPAC device consisted of three parts, ECR ion source section, GYRAC section, and PLEIADE section. ECR ion source section and PLEIADE section were designed using several multi-turn solenoid coils and sextupole magnets, and GYRAC section was designed using 10 turns coil. The structure of ECR-IPAC device was the cylindrical shape, and the total length was 1024 mm and the maximum diameter was 580 mm. The magnetic field distribution, which maintains the stable acceleration of plasma, was generated on the acceleration center axis throughout three sections. In addition, the electric field for efficient acceleration of electrons was generated in the resonance cavity by supplying microwave of 2.45 GHz.

Utility of weekly docetaxel combined with preoperative radiotherapy for locally advanced esophageal cancer from pathological analysis.

Esophageal squamous cell cancer (ESCC) is a high-grade carcinoma that is treated with multidisciplinary approaches, including chemoradiotherapy (CRT) followed by surgery. Despite some success with these therapies, overall survival remains poor. In order to investigate a newer CRT regimen, we designed a comparative study to evaluate preoperative CRT using docetaxel (DOC) or 5-Fluorouracil and cisplatin (FU+CDDP [FP] therapy) for treatment of resectable ESCC. In a retrospective review of patients with resectable, locally advanced ESCC, 95 patients received preoperative CRT between 2001 and 2007. CRT was administered using either FP (n = 40) or DOC (n = 55). Pathological response and clinical outcomes were compared between the two groups. Hazard ratios and time-to-event analyses were used to assess outcomes; the ratios were controlled by multivariate logistic regression analysis of potential prognostic factors, and survival was presented with Kaplan-Meier curves. In the FP group, a significant curative effect was observed on the basis of pathological examination of postoperative lesions. However, the DOC group presented a significantly better prognosis on the basis of cumulative survival rates. Logistic regression analysis revealed that the presence of five or more lymph node metastases was an independent predictor of reduced survival. Patients with lymph node metastasis exhibited a better prognosis in the DOC group than those in the FP group. Preoperative CRT for locally advanced esophageal cancer using DOC results in similar or better long-term outcomes compared with FP-based CRT. Therefore, CRT using DOC is a promising therapy option for esophageal cancer.

SU-E-T-142: Evaluation of the Energy Dependence of Gafchromic EBT3 Film for Electron Beams.

PURPOSE: To evaluate the energy dependence of Gafchromic EBT3 film for establishing a quality assurance method of bolus electron conformal radiotherapy. METHODS: We irradiated electron beam to EBT3 films, which were set in the water tank. The linear accelerator used was Varian Clinac 21EX. The energy of electron beams were 9 and 12 MeV. The irradiated field size was 10×10 cm2 and the source to surface distance was 100 cm. The depths of measurement were 22 (depth of dose maximum; dmax), 31, and 37 mm for 9 MeV and 28 (dmax), 43, and 50 mm for 12 MeV. The irradiated doses were 25, 50, 75, 100, 150, 200, and 300 cGy. EBT3 films were readout with a flat-bed scanner 48 hours after irradiation, and the optical density (OD) curve was obtained for each beam energy and depth. The OD curves were approximated by a third-order polynomial. The doses were evaluated at netOD 0.1 and 0.3 from the approximated curves. RESULTS: The differences of the evaluated doses from those for 9 MeV at 22 mm depth were from 2 to 14 % for netOD=0.1, and from 1 to 13 % for netOD=0.3, respectively. The netOD curves of dmax for both energies showed good agreement, while large discrepancy was found in the deeper depths. CONCLUSIONS: The dependence of dose response of EBT3 film on electron beam energy was small at dmax, while it increased at deeper depth in the present study. It can be considered that the discrepancy was caused by setup error because dose gradient was steeper at the deeper region. In future work, we will perform more precise measurement with a solid phantom to evaluate the energy dependence of EBT3 film.

SU-E-T-497: Study of Restricted Mass Stopping Power Ratio in Small Electron Tube Fields.

PURPOSE: Electron tubes with small radii are useful to treat narrow regions which cannot accommodate normal electron applicators. In small electron fields, it is not trivial to estimate restricted mass stopping power ratio (MSR), which is needed to evaluate dose from ion chamber measurement. We studied MSRs in small electron tube fields using the Monte Carlo simulation. METHODS: Electron tubes with radii, 3 and 2.5 cm, were used in this study. Nominal electron energies were 6 and 9 MeV. There were two types of tubes. One has a normal cut but the other has a 45-degree cut. For the normal cut tube, percent depth dose (PDD) in water was evaluated along the center of axis (CAX) of a beam. For the 45-degree cut tube, PDD was evaluated along the vertical line from the intersection of the CAX and the phantom surface with 45-degree gantry angle. The MSRs and mean electron energies were calculated using the Monte Carlo simulation. RESULTS: We found good agreement between the measured and calculated PDDs. The changes of mean energies from those in the 10×10 cm2 field at the depth of maximum dose (dmax) were very small for the normal cut electron tubes. For the 45-degree cut tubes, the changes of mean energies at dmax were less than 1 MeV. The MSRs in the normal cut tube fields were almost the same as those in the 10×10 cm2 field at the corresponding depths. The MSRs for the 45-degree cut tubes deviated from those in the 10×10 cm2 by about 1% (1.5 % at most). CONCLUSIONS: We evaluated the mean energies and MSRs in small electron tube fields. The deviations of them from the values in the 10×10 cm2 were small. The maximum difference of MSR was 1.5% in 45-degree cut tube fields. This work was supported by KAKENHI (23791449), Japan Society for the Promotion of Science, and Cancer Professional Training Plan, The Ministry of Education, Culture, Sports, Science and Technology, Japan.

Dynamic alteration of regional cerebral blood flow during carotid compression and proof of reversibility.

BACKGROUND: It is difficult to non-invasively visualize changes in regional cerebral blood flow caused by manual compression of the carotid artery. PURPOSE: To visualize dynamic changes in regional cerebral blood flow during and after manual compression of the carotid artery. MATERIAL AND METHODS: Two healthy volunteers were recruited. Anatomic features and flow directions in the circle of Willis were evaluated with time-of-flight magnetic resonance angiography (MRA) and two-dimensional phase-contrast (2DPC) MRA, respectively. Regional cerebral blood flow was visualized with territorial arterial spin-labeling magnetic resonance imaging (TASL-MRI). TASL-MRI and 2DPC-MRA were performed in three states: at rest, during manual compression of the right carotid artery, and after decompression. In one volunteer, time-space labeling inversion pulse (Time-SLIP) MRA was performed to confirm collateral flow. RESULTS: During manual carotid compression, in one volunteer, the right thalamus changed to be fed only by the vertebrobasilar system, and the right basal ganglia changed to be fed by the left internal carotid artery. In the other volunteer, the right basal ganglia changed to be fed by the vertebrobasilar system. 2DPC-MRA showed that the flow direction changed in the right A1 segment of the anterior cerebral artery and the right posterior communicating artery. Perfusion patterns and flow directions recovered after decompression. Time-SLIP MRA showed pial vessels and dural collateral circulation when the right carotid artery was manually compressed. CONCLUSION: Use of TASL-MRI and 2DPC-MRA was successful for non-invasive visualization of the dynamic changes in regional cerebral blood flow during and after manual carotid compression.

Morphological changes and viability of Cryptosporidium parvum sporozoites after excystation in cell-free culture media.

Cryptosporidium parvum, belonging to the phylum Apicomplexa, is a major cause of waterborne gastroenteritis throughout the world. The sporozoites are thought to invade host enterocytes using an active process termed gliding motility. However, the biological and morphological changes within the sporozoites during this process are not fully understood. In the present study, excysted sporozoites of C. parvum were analysed ultrastructurally in vitro and their viability was evaluated using fluorescent dyes. The sporozoites excysted from oocysts changed morphologically from banana-shaped to rod-shaped and finally to a rounded shape, in culture media in 3 h. Transmission microscopy revealed that the distance between the apical end and the nucleus was markedly reduced, dense granules were present close to the rhoptry in the apical region, amylopectin granules were absent, and membranes of round sporozoites were less clear. A fluorescent assay showed that the rate of survival decreased from 89% to 56% at 0-3 h (84.3% for banana-shaped and 49.2% for rod-shaped sporozoites). Therefore, post-excysted sporozoites in vitro underwent morphological changes and a rapid loss of viability. This staining method is useful, inexpensive and provides an alternative to more costly and intensive flow cytometric assays or infectivity assays with host cells in vitro.

Development of a system that generates structured reports for chest x-ray radiography.

OBJECTIVES: Radiology reports are typically made in narrative form; this is a barrier to the implementation of advanced applications for data analysis or a decision support. We developed a system that generates structured reports for chest x-ray radiography. METHODS: Based on analyzing existing reports, we determined the fundamental sentence structure of findings as compositions of procedure, region, finding, and diagnosis. We categorized the observation objects into lung, mediastinum, bone, soft tissue, and pleura and chest wall. The terms of region, finding, and diagnosis were associated with each other. We expressed the terms and the relations between the terms using a resource description framework (RDF) and developed a reporting system based on it. The system shows a list of terms in each category, and modifiers can be entered using templates that are linked to each term. This system guides users to select terms by highlighting associated terms. Fifty chest x-rays with abnormal findings were interpreted by five radiologists and reports were made either by the system or by the free-text method. RESULTS: The system decreased the time needed to make a report by 12.5% compared with the free-text method, and the sentences generated by the system were well concordant with those made by free-text method (F-measure = 90%). The results of the questionnaire showed that our system is applicable to radiology reports of chest x-rays in daily clinical practice. CONCLUSIONS: The method of generating structured reports for chest x-rays was feasible, because it generated almost concordant reports in shorter time compared with the free-text method.

Unconventional ferroelectric transition in the multiferroic compound TbMnO3 revealed by the absence of an anomaly in c-polarized phonon dispersion.

TbMnO(3) exhibits a spontaneous electric polarization along c concomitantly with a spiral spin ordering modulated along b below T_{C} = 28 K. We have performed inelastic x-ray scattering measurements on a single crystal of TbMnO(3) to clarify whether phonon anomalies related to the ferroelectricity exist. We measured transverse modes, especially the Mn-O-Mn bending mode polarized along c and propagating along b, which we expect is most relevant to the ferroelectricity. However, no anomaly was found in the phonon dispersion below 50 meV across T_{C}. The present result suggests that the mechanism of ferroelectricity in TbMnO(3) is different from that of a conventional displacive-type ferroelectric. The weak coupling between electric polarization and lattice in TbMnO(3) strongly suggests that the ferroelectricity is mainly derived from the spiral spin ordering.

Cycloidal spin order in the a-axis polarized ferroelectric phase of orthorhombic perovskite manganite.

The ferroelectric state in an orthorhombic perovskite RMnO3 (R=Gd0.7Tb0.3) was proved by neutron scattering studies to show the cycloidal spin state with the ab-spiral plane and the spin-helicity dependent polarization vector along the a axis, sharing the microscopic origin (inverse Dzyaloshinskii-Moriya interaction) with the more widely observed P||c state (e.g., for R=Tb and Dy) with the bc-spiral plane. The magnetic-field induced polarization flop from P||c to P||a as well known for RMnO3 is thus assigned to the orthogonal flop of the spin spiral plane from bc to ab.

Prevention of corticosteroid-induced osteonecrosis in rabbits by intra-bone marrow injection of autologous bone marrow cells.

OBJECTIVES: Femoral head osteonecrosis (ON) is a serious complication of steroid administration. We evaluated bone marrow transplantation (BMT) for preventing corticosteroid-induced ON. METHODS: Rabbits, injected with methylprednisolone (MPSL; 20 mg/kg), were divided into four groups: (i) MPSL alone; MPSL injection only, (ii) MPSL+needling; 2 days after MPSL injection, a hole (1.2 mm diameter) was drilled from the outer cortex 2.5 cm distal to the proximal end of the greater trochanter, (iii) MPSL+saline; 2 days after MPSL injection, 2 ml saline was injected directly into the bone marrow cavity, and (iv) MPSL+BMT; 2 days after MPSL injection, 1 x 10(7)/2 ml bone marrow cells (BMCs) were injected directly into the bone marrow cavity. Platelets, fibrinogen, prothrombin time and total cholesterol in peripheral blood were measured before and after treatment. Tissues were stained with haematoxylin and eosion and terminal deoxynucleotidyl-mediated deoxyuridine triphosphate nick-end labelling stain and immunostained for VEGF, while cell proliferation and viability of whole BMCs in the femur were analysed by cell cycle analysis and [(3)H]-thymidine uptake. RESULTS: The ON incidence in rabbits treated with MPSL alone, MPSL+needling and MPSL+saline was 72.7, 70.0 and 66.7%, respectively, while in the MPSL+BMT group, the incidence was 0%. Serological findings in the MPSL+BMT group were almost normalized. VEGF and TUNEL staining were reduced in the MPSL+BMT group compared with all other groups. There were significantly fewer BMCs in G1 phase from the MPSL+BMT group than the other groups, while uptake of [(3)H]-thymidine was significantly increased. CONCLUSION: Direct injection of autologous BMCs into femurs prevents corticosteroid-induced ON following treatment with high-dose, short-term steroids.

Targeted disruption of Aurora A causes abnormal mitotic spindle assembly, chromosome misalignment and embryonic lethality.

Aurora A (also known as STK15/BTAK in humans), a putative oncoprotein naturally overexpressed in many human cancers, is a member of the conserved Aurora protein serine/threonine kinase family that is implicated in the regulation of G(2)-M phases of the cell cycle. In vitro studies utilizing antibody microinjection, siRNA silencing and small molecule inhibitors have indicated that Aurora A functions in early as well as late stages of mitosis. However, due to limitations in specificity of the techniques, exact functional roles of the kinase remain to be clearly elucidated. In order to identify the physiological functions in vivo, we have generated Aurora A null mouse embryos, which show severe defects at 3.5 d.p.c. (days post-coitus) morula/blastocyst stage and lethality before 8.5 d.p.c. Null embryos at 3.5 d.p.c. reveal growth retardation with cells in mitotic disarray manifesting disorganized spindle, misaligned and lagging chromosomes as well as micronucleated cells. These findings provide the first unequivocal genetic evidence for an essential physiological role of Aurora A in normal mitotic spindle assembly, chromosome alignment segregation and maintenance of viability in mammalian embryos.

Electron microscopic observation of cytoskeletal frame structures and detection of tubulin on the apical region of Cryptosporidium parvum sporozoites.

Cryptosporidium parvum is an intracellular protozoan parasite belonging to the phylum Apicomplexa, and a major cause of waterborne gastroenteritis throughout the world. Invasive zoites of apicomplexan parasites, including C. parvum, are thought to have characteristic organelles on the apical apex; however, compared with other parasites, the cytoskeletal ultrastructure of C. parvum zoites is poorly understood. Thus, in the present study, we ultrastructurally examined C. parvum sporozoites using electron microscopy to clarify the framework of invasive stages. Consequently, at the apical end of sporozoites, 3 apical rings and an electron-dense collar were seen. Two thick central microtubules were seen further inside sporozoites and extended to the posterior region. Using anti-alpha and -beta tubulin antibodies generated from sea urchin and rat brain, both antibodies cross-reacted at the apical region of sporozoites in immunofluorescent morphology. The molecular mass of C. parvum alpha tubulin antigen was 50 kDa by Western blotting and the observed apical cytoskeletal structures were shown to be composed of alpha tubulin by immunoelectron microscopy. These results suggested that C. parvum sporozoites were clearly different in their cytoskeletal structure from those of other apicomplexan parasites.