Basilar invagination is a developmental anomaly of the craniovertebral junction in which the odontoid abnormally prolapses into the foramen magnum. It is also associated with Chiari malformation, syringomyelia, and hydrocephalus. Patients require surgical treatment to prevent progression of neurological symptoms, but assessment of anterior or posterior decompression can be difficult owing to bone instability and ambiguous compression of neural structures. Here, we describe a case of basilar invagination in a young adult. He presented with neurological symptoms, including syringomyelia, 3 months after a traffic trauma that might have led to instability of the bony structures. Since it was unclear whether the instability of the bony structures contributed to the clinical deterioration, the patient was first treated using halo-vest fixation. Significant improvements were observed in both neurological symptoms and magnetic resonance images. These results justified the invasive fixation and the patient was treated further with an occipito-cervical fusion ; good results were achieved in this case. Owing to the invasiveness of the procedure, occipito-cervical fixation should only be adopted following strict indication criteria. Halo-vest fixation was effective in treating the instability of the bony structures and as a trial treatment for permanent fixation.
Retropharyngeal abscess-like lesions are occasionally seen in computed tomography (CT) imaging of patients with Kawasaki disease (KD) and these patients often undergo unnecessary surgery. We could distinguish the lesions from true abscesses by measuring their Hounsfield unit values (HUs).
Human induced pluripotent stem cells (hiPSCs) are a promising source of cells for medical applications. Recently, the development of polydimethylsiloxane (PDMS) microdevices to control the microenvironment of hiPSCs has been extensively studied. PDMS surfaces are often treated with low-pressure air plasma to facilitate protein adsorption and cell adhesion. However, undefined molecules present in the serum and extracellular matrix used to culture cells complicate the study of cell adhesion. Here, we studied the effects of vitronectin and ?-globulin on hiPSC adhesion to plasma-treated and untreated PDMS surfaces under defined culture conditions. We chose these proteins because they have opposite properties: vitronectin mediates hiPSC attachment to hydrophilic siliceous surfaces, whereas ?-globulin is adsorbed by hydrophobic surfaces and does not mediate cell adhesion. Immunostaining showed that, when applied separately, vitronectin and ?-globulin were adsorbed by both plasma-treated and untreated PDMS surfaces. In contrast, when PDMS surfaces were exposed to a mixture of the two proteins, vitronectin was preferentially adsorbed onto plasma-treated surfaces, whereas ?-globulin was adsorbed onto untreated surfaces. Human iPSCs adhered to the vitronectin-rich plasma-treated surfaces but not to the ?-globulin-rich untreated surfaces. On the basis of these results, we used perforated masks to prepare plasma-patterned PDMS substrates, which were then used to pattern hiPSCs. The patterned hiPSCs expressed undifferentiated-cell markers and did not escape from the patterned area for at least 7 days. The patterned PDMS could be stored for up to 6 days before hiPSCs were plated. We believe that our results will be useful for the development of hiPSC microdevices.
A new technical standard for X-ray computed tomography (CT) has been published by the National Electrical Manufacturers Association (NEMA) that allows the Alert Value and Notification Value for cumulative dose to be configurable by CT systems operators in conjunction with the XR-25 (Dose check) standard. In this study, a decision method of the Notification Values for reducing the radiation dose was examined using the dose index registry (DIR) system, during 122 continuous days from August 1, 2012 to November 30, 2012. CT images were obtained using the Discovery CT 750HD (GE Healthcare) and the dose index was calculated using the DoseWatch DIR system. The CT dose index-volume (CTDIvol) and dose-length product (DLP) were output from the DIR system in comma-separated value (CSV) file format for each examination protocol. All data were shown as a schematic boxplot using statistical processing software. The CTDIvol of a routine chest examination showed the following values (maximum: 23.84 mGy; minimum: 2.55 mGy; median: 7.60 mGy; 75% tile: 10.01 mGy; 25% tile: 6.54 mGy). DLP showed the following values (maximum: 944.56 mGy·cm; minimum: 97.25 mGy·cm; median: 307.35 mGy·cm; 75% tile: 406.87 mGy·cm; 25% tile: 255.75 mGy·cm). These results indicate that the 75% tile of CTDIvol and DLP as an initial value proved to be safe and efficient for CT examination and operation. We have thus established one way of determining the Notification Value from the output of the DIR system. Transfer back to the protocol of the CT and automated processing each numeric value in the DIR system is desired.
Hypoxia occurs during the development of uterine cervical cancer and is considered to correlate with its invasion. Hypoxia promotes both the invasiveness and the metastasis of cancer cells through urokinase-type plasminogen activator receptor (uPAR) expression. The aim of this study was to evaluate the correlation between uPAR mRNA level and clinical prognostic factors of uterine cervical cancer.
A 65-year-old man was admitted for detailed examination of a growing nodular shadow in the left lung. The nodular shadow was initially detected in a routine chest X-ray check-up in March 2012 that warranted regular chest X-ray follow-up. The nodular shadow increased in size from 12 × 15?mm to 15 × 20?mm within five months. The calculated tumor doubling time (TDT) in our case was approximately 132.2 days. A malignant tumor was strongly suspected based on the rapid growth, and tumorectomy was thus performed. Cartilaginous tissue accounted for most of the pathological specimen, but a small amount of an epithelial component was observed histologically, and we diagnosed a hamartoma. Hamartoma generally shows slow annual growth, but it is important to recognize that rapid enlargement occurs in some cases.
Understanding the substrate recognition mechanism of ?-secretase is a key step for establishing substrate-specific inhibition of amyloid ?-protein (A?) production. However, it is widely believed that ?-secretase is a promiscuous protease and that its substrate-specific inhibition is elusive. Here we show that ?-secretase distinguishes the ectodomain length of substrates and preferentially captures and cleaves substrates containing a short ectodomain. We also show that a subset of peptides containing the CDCYCxxxxCxCxSC motif binds to the amino terminus of C99 and inhibits A? production in a substrate-specific manner. Interestingly, these peptides suppress ?-secretase-dependent cleavage of APP, but not that of sialyltransferase 1. Most importantly, intraperitoneal administration of peptides into mice results in a significant reduction in cerebral A? levels. This report provides direct evidence of the substrate preference of ?-secretase and its mechanism. Our results demonstrate that the ectodomain of C99 is a potent target for substrate-specific anti-A? therapeutics to combat Alzheimers disease.
Lifespan extension has been demonstrated in dwarfism mouse models relative to their wild-type. The spontaneous dwarf rat (SDR) was isolated from a closed colony of Sprague-Dawley (SD) rats. Growth hormone deficiencies have been indicated to be responsible for dwarfism in SDR. Survival time, the markers of oxidative stress, antioxidant enzymes, and resistance to hyperoxia were compared between SDR and SD rats, to investigate whether SDR, a dwarfism rat model, also extends lifespan and has an enhanced resistance to oxidative stress. SDRs lived 38% longer than SD rats on average. This is the first report to show that dwarf rats exhibit lifespan extensions similar to Ames and Snell mice. Decreased 8-oxo-2-deoxyguanosine (8-oxodG) content, a marker of oxidative DNA damage, indicated suppressed oxidative stress in the liver, kidney, and lung of SDRs. Increased glutathione peroxidase enzyme activity was consistent with decreased 8-oxodG content in the same tissues. The heart and brain showed a similar tendency, but this was not significant. However, the catalase and superoxide dismutase enzyme activities of SDRs were not different from those of SD rats in any tissue. This was not what the original null hypothesis predicted. SDRs had potent resistance to the toxicity associated with high O2 (85%) exposure. The mean survival time in SDRs was more than 147% that of SD rats with 168h O2 exposure. These results suggest that the enhanced resistance to oxidative stress of SDRs associated with enhanced hydrogen peroxide elimination may support its potential role in lifespan extension.
Ubiquitin-like (UBL)-ubiquitin-associated (UBA) proteins, including Dsk2 and Rad23, act as delivery factors that target polyubiquitinated substrates to the proteasome. We report here that the Dsk2 UBL domain is ubiquitinated in yeast cells and that Dsk2 ubiquitination of the UBL domain is involved in Dsk2 stability, depending on the Dsk2 UBA domain. Also, Dsk2 lacking ubiquitin chains impaired ubiquitin-dependent protein degradation and decreased the interaction of Dsk2 with polyubiquitinated proteins in cells. Moreover, Dsk2 ubiquitination affected ability to restore the temperature-sensitive growth defect of dsk2?. These results indicate that ubiquitination in the UBL domain of Dsk2 has in vivo functions in the ubiquitin-proteasome pathway in yeast.
To determine whether the mitochondria or cytoplasm produces superoxide during ischemia-reperfusion of the brain, we analyzed lucigenine-enhanced chemiluminescence emission in slices of brain tissue prepared from manganese-superoxide dismutase (Mn-SOD)-deficient (Sod2-deficient) and copper and zinc-superoxide dismutase (Cu,Zn-SOD)-deficient (Sod1-deficient) mice during oxygenation and hypoxia-reoxygenation. The steady-state level of chemiluminescence under oxygenated conditions was significantly enhanced by a lack of either Sod. We hypothesize that the enhanced chemiluminescence produced by Sod2 and Sod1 deficiency reflects in situ superoxide generation in the mitochondria and cytoplasm, respectively. Based on this hypothesis, the major site of intracellular superoxide generation was assumed to be the cytoplasm. However, mitochondria occupy less cellular space than the cytoplasm. In terms of volume, the superoxide concentration is assumed to be higher in mitochondria than in the cytoplasm. Mn-SOD activity was 18% of the Cu,Zn-SOD activity observed in the wild-type mouse brain. However, when mitochondrial SOD activity was expressed as per volume, it was assumed to be equal to that observed in the cytoplasm. This imbalance between superoxide and SOD activity is expected to cause mitochondrial oxidative damage. The chemiluminescence intensity increased significantly during reoxygenation and was enhanced by Sod2 deficiency but was not significantly affected by Sod1 deficiency. The superoxide concentration in the reoxygenated brain would be higher in the mitochondria than in the cytoplasm. The present study indicated that the major site of intracellular superoxide generation in the brain during oxygenation is the cytoplasm, whereas it is the mitochondria during reoxygenation.
In the early stages of epithelial ovarian cancer, histopathological grading is important. However, the grading of ovarian clear cell carcinoma (OCCC) remains controversial. We aimed to identify irregular giant nuclear cells (IGNCs) by a simple method in clinical practice, and to evaluate the prognostic value of IGNCs in pT1 OCCC. Eighty-seven pT1 OCCC patients who underwent initial surgery at Jikei University Kashiwa Hospital, Chiba, Japan, were retrospectively assessed. Paraffin-embedded tissue sections (PTSs) stained with hematoxylin and eosin were reviewed. Giant nuclear cells (GNCs) were defined as cells with a nuclear length of more than twice the median nuclear length. GNCs with irregular nuclear circumferences were defined as IGNCs. Cases where one or more GNCs existed and where IGNCs accounted for >10% of the GNCs were classified as IGNC-positive. We also attempted to identify IGNCs on touch imprint cytology smears (TICSs). Among the 87 cases, 68 were IGNC-negative and 19 were IGNC-positive. The 5-year disease-free and overall survival rates were 88.9% and 90.3% in the total patients, 98.3% and 100% in the IGNC-negative group, and 59.7% and 62.0% in the IGNC-positive group, respectively. These survival rates were significantly lower in the IGNC-positive group than in the IGNC-negative group (adjusted hazard ratio = 14, 95% confidence interval = 2.7-124 and adjusted hazard ratio?=?25, 95% confidence interval = ?2.9-768, respectively). Prognostic differences were not identified for other factors. IGNC identification on 28 available TICSs predicted IGNC identification on PTSs (sensitivity = 50.0%, specificity = 100%, P = 0.007). The presence of IGNCs has clinical and prognostic value for pT1 OCCC.
Since Harman proposed the "free-radical theory of aging", oxidative stress has been postulated to be a major causal factor of senescence. The accumulation of oxidative stress-induced oxidatively modified macromolecules, including protein, DNA and lipid, were found in tissues during the aging process; however, it is not necessarily clear which factor is more critical, an increase in endogenous reactive oxygen and/or a decrease in anti-oxidative defense, to the age-related increase in oxidative damage. To clarify the increasing production of reactive oxygen with age, we examined reactive oxygen-dependent chemiluminescent (CL) signals in ex vivo brain slices prepared from different-aged animal brains during hypoxia-reoxygenation treatment using a novel photonic imaging method. The CL signal was intensified during reoxygenation. The signals in SAMP10 (short-life strain) and SAMR1 (control) brain slices increased with aging. The slope of the increase of CL intensity with age in P10 was steeper than in R1. Age-dependent increase of CL intensity was also observed in C57BL/6 mice, Wistar rats and pigeons; however, superoxide dismutase (SOD) activity in the brain did not change with age. These results suggest that reactive oxygen production itself increased with aging. The rate of age-related increases of CL intensity was inversely related to the maximum lifespan of animals. We speculate that reactive oxygen might be a signaling molecule and its levels in tissue might determine the aging process and lifespan. Decelerating age-related increases of reactive oxygen production are expected to be a potent strategy for anti-aging interventions.
Surgical resections, such as peritoneal stripping (peritonectomy) are performed for disseminated diaphragmatic lesions of advanced ovarian cancer. This study retrospectively investigated the incidental events of diaphragmatic surgery. The records of patients with advanced mullerian carcinomas, including ovarian, primary peritoneal and fallopian carcinomas, who underwent diaphragmatic surgery were reviewed. Based on our criteria, stripping was performed for surface disease on the diaphragm, and full-thickness resection was performed for bulky disease. In certain cases, both procedures were performed. We analyzed intra- and post-operative incidental events in 82 patients. The ?(2) and Fishers exact tests were used in the statistical analysis. There were 82 stage III-IV cases of which 56 patients underwent stripping, 12 underwent full-thickness resection and 14 patients underwent both procedures. Unexpected open chest surgery following stripping occurred in 1 out of 63 patients (1.6%) in the primary, 4 out of 13 patients (30.8%) in the interval and 0 out of 6 patients (0.0%) in the secondary debulking surgery groups. The incidence of unexpected open chest surgery was high in the interval debulking surgery group (p<0.001). Regarding post-operative events, accumulation of pleural effusion was identified in 43 patients (52.4%). The incidence of pleural effusions was not significantly different between the two procedures. No complications were encountered, nor was a chest tube required, during unexpected open chest surgery and postoperative pleural effusions. Therefore, it was concluded that special attention should be paid during interval debulking surgery even though it was possible for surgical resections of diaphragmatic lesions to be performed safely.
We describe the "chopsticks" technique of simultaneous use of two instruments held in one hand during tonsillectomy. The technique allows the surgeon to simultaneously, retract the tonsils, clear the blood, and cauterize the tissue and thus achieve rapid hemostasis and a more efficient tonsillectomy.
We analyse, from a mathematical point of view, the global stability of equilibria for models describing the interaction between infectious agents and humoral immunity. We consider the models that contain the variables of pathogens explicitly. The first model considers the situation where only a single strain exists. For the single strain model, the disease steady state is globally asymptotically stable if the basic reproductive ratio is greater than one. The other models consider the situations where multiple strains exist. For the multi-strain models, the disease steady state is globally asymptotically stable. In the model that does not explicitly contain an immune variable, only one strain with the maximum basic reproductive ratio can survive at the steady state. However, in our models explicitly involving the immune system, multiple strains coexist at the steady state.
In male broad-horned flour beetles, Gnatocerus cornutus, losers of conflicts avoid fighting at subsequent encounters. The loser effect lasts for 4 days. It is considered that the memory of losing remains for 4 days. The duration of the memory is expected to affect the fitness, and the duration, 4 days, is expected to be optimal. We consider the fitness of a mutant in an homogeneous population to obtain the optimal duration. Here we carry out simulations using an individual-based model. The results suggest that the trade-off of getting mating chances and avoiding damage can cause the optimal duration of the memory, and that the decay in time of the female population is an important factor.
In this paper, we consider the global stability of the models which incorporate humoural immunity or cell-mediated immunity. We consider the effect of loss of a pathogen, which is called the absorption effect when it infects an uninfected cells. We construct Lyapunov functions for these models under some conditions of parameters, and prove the global stability of the interior equilibria. It is impossible to remove the condition of parameters for the model incorporating humoural immunity.
In Western countries, the response of gastric cancer to chemotherapy is evaluated by assessing measurable metastatic lesions (MMLs) according to the response evaluation criteria in solid tumors (RECIST). In Japan, the response of primary lesions is assessed according to local Japanese criteria. We compared the response to chemotherapy as evaluated by these two sets of criteria.
Dwarf animal models can provide new models for aging research. For the spontaneous dwarf rat (SDR), a dwarf strain derived from the Sprague-Dawley (SD) rat, no data relevant to aging research are available. The present study aimed to examine its growth, hormonal background, lifespan and age-related diseases.
Since Harman proposed the "free-radical theory of aging", oxidative stress is postulated to be a major causal factor of senescence. Accumulation of oxidative stress-induced oxidatively modified macromolecules including protein, DNA, and lipid, were found in tissues during the aging process. However, it is not necessarily clear which factor is more critical for an increase in endogenous reactive oxygen and/or decrease in antioxidative defense, to the age-related increase in oxidative damage. To clarify the production of reactive oxygen increasing with age, we examined reactive oxygen-dependent chemiluminescent (CL) signals in ex-vivo brain slices prepared from different aged animal brain during hypoxia-reoxygenation treatment using a novel photonic imaging method. CL signal was intensified during reoxygenation. The signals in SAMP10 (short life strain) and SAMR1 (control) brain slices increased with aging. The slope of increase of CL intensity with age in P10 was steeper than those in R1. Age-dependent increase of CL intensity was also observed in C57BL/6 mouse, Wistar rat, and pigeon. However, SOD activity in brain was not changed with age. These results suggest that reactive oxygen production itself increase with aging. The rate of age-related increase of CL intensity was inversely related to the maximum life span of the animals. We speculate that reactive oxygen may be a kind of signal for aging and its levels in tissue may determine the aging process and life span. To decelerate the age-related increases of reactive oxygen production is expected as a potent strategy for anti-aging interventions.
Caloric and food restriction attenuate oxidative stress. The effect of aging and every-other-day (EOD) feeding on oxygen radical-dependent chemiluminescent intensity was examined in ex vivo brain slices from Fischer rats during oxygenation and hypoxia-reoxygenation with lucigenin, a chemilumigenic probe used for detecting superoxide anion radicals. The chemiluminescent intensity increased during reoxygenation after hypoxic treatment, and the chemiluminescence in the brain slices at the baseline and during reoxygenation increased with age. However, no difference was observed in the superoxide-dependent chemiluminescence between brain slices prepared from the aged rats fed EOD and those fed ad libitum. Our results indicated that age-dependent increases in superoxide production might be associated with enhanced oxidative stress in aged Fischer rat brains. However, the present study newly indicated that decreased superoxide production might not be a major causal factor in caloric and food restriction attenuated oxidative stress.
We report a robust display technology for the screening of disulfide-rich peptides, based on cDNA-protein fusions, by developing a novel and versatile puromycin-linker DNA. This linker comprises four major portions: a ligation site for T4 RNA ligase, a biotin site for solid-phase handling, a reverse transcription primer site for the efficient and rapid conversion from an unstable mRNA-protein fusion (mRNA display) to a stable mRNA/cDNA-protein fusion (cDNA display) whose cDNA is covalently linked to its encoded protein and a restriction enzyme site for the release of a complex from the solid support. This enables not only stabilizing mRNA-protein fusions but also promoting both protein folding and disulfide shuffling reactions. We evaluated the performance of cDNA display in different model systems and demonstrated an enrichment efficiency of 20-fold per selection round. Selection of a 32-residue random library against interleukin-6 receptor generated novel peptides containing multiple disulfide bonds with a unique linkage for its function. The peptides were found to bind with the target in the low nanomolar range. These results show the suitability of our method for in vitro selections of disulfide-rich proteins and other potential applications.
Xeroderma pigmentosum (XP), a genetic disorder in DNA nucleotide excision repair, is characterized by skin hypersensitivity to sunlight and progressive neurological impairment. Laryngeal dystonia and vocal cord paralysis are complications that can arise in older XP group A (XPA) patients. We report three patients with XPA being administered low-dose levodopa (0.3-1.5 mg/kg/day) for laryngeal dystonia. Patients were aged from 13 to 18 years, exhibited paroxysmal choking and inspiratory stridor, and were diagnosed with laryngeal dystonia. Two XPA patients responded to low-dose levodopa, and paroxysmal choking and involuntary movements resolved, although one of the two patients showed incomplete resolution due to suspected vocal cord paralysis. The other patient was unable to tolerate the medication because of a transient decrease of muscle tone in the extremities. We previously reported a decreased immunostaining of dopaminergic (DA) terminals in the basal ganglia of XPA patients, which may be involved in laryngeal dystonia. Low-dose levodopa has been reported to alleviate DA receptor supersensitivity in tic patients, while laryngeal dystonia occurs in patients with tardive dyskinesia caused by DA receptor supersensitivity. Thus, low-dose levodopa may improve laryngeal dystonia by alleviating DA receptor supersensitivity in XPA patients. We recommend that low-dose levodopa be used for treatment of paroxysmal respiratory disturbances and/or involuntary movements in XPA patients.
The superoxide-dependent chemiluminescent intensity in different brain regions was examined in ex vivo tissue slices of rat brain during normoxia and hypoxia-reoxygenation with lucigenin. The chemiluminescent intensity increased during reoxygenation after hypoxic treatment. There was a higher level of chemiluminescent intensity in the hippocampus during normoxia, and a lower level in the white matter during normoxia and hypoxia-reoxygenation. A weak correlation was found between the chemiluminescent intensity and the glucose uptake rate during normoxia. Then we examined whether hypoxic strength correlates to superoxide generation. The chemiluminescent intensity increased in a hypoxic strength-dependent manner. The generation mechanism of superoxide was examined using carbonyl cyanide m-chlorophenylhydrazone (CCCP), a mitochondrial uncoupler, genipin, an inhibitor for uncoupling protein-2, alloprinol, a xanthine oxidase inhibitor, or apocynin, an NADPH oxidase inhibitor. The chemiluminescent signal was significantly inhibited by CCCP under normoxic condition and enhanced by genipin during normoxia and hypoxia-reoxygenation, but not by allopurinol or apocynin. These results suggest that superoxide generation is high in the hippocampus during normoxia and low in the white matter during normoxia and hypoxia-reoxygenation, superoxide generation in the hypoxia-reoxygenation brain correlates with the strength of hypoxia influenced by oxygen delivery, and mitochondrion is the major sites of intracellular superoxide generation.
To generate well-defined warm dense state for evaluating electrical conductivity by using pulsed-power discharge, we have proposed an isochoric heating of foamed metal. Isochoric heating can be achieved by surrounding the foamed metal with a rigid-walled sapphire capillary. We evaluate the temperature and electrical conductivity of the foam?plasma based on the line-pair method of the foam?plasma emission and on the voltage-current waveforms. The electrical conductivity observed agrees with previous experiments and predictions. Thus, the proposed technique yields the electrical conductivity of warm dense matter with a well-defined temperature.
We found that the ubiquitin-conjugating enzyme E2-EPF mRNA is highly expressed in cervical squamous cancer relative to normal tissues and its expression levels positively correlate with clinical stage. Reduction of E2-EPF protein levels by >80% using shRNA decreases the expression levels of HIF-1?, and the proliferation, invasion and tumorigenicity of SiHa, a cervical squamous cancer cell line. E2-EPF knockdown also increases the chemosensitivity to topoisomerase I inhibitor (topotecan) and II (etoposide and doxorubicin). Our results suggest that E2-EPF is associated with the growth and aggressivity of cervical tumor cells. Targeting the E2-EPF pathway may have potential clinical applications for the treatment of cervical cancer.
We report a case of a 31-year-old Japanese woman with an uncommon shape of epiglottis misleading as acute epiglottitis. She presented with high fever, arthralgia, general fatigue and strong throat pain. Laryngeal fiberscopy showed a markedly swollen epiglottis suggestive of acute epiglottitis, though she had no signs of asphyxia. A careful observation and detailed medical history ruled out acute epiglottitis. However, without clinical discretion, it might have been misinterpreted as acute epiglottitis. She was diagnosed later with Behçets disease, which is reported to present pharyngeal stenosis. Two years later, a repeat laryngeal fiberscopy showed exactly the same appearance of the epiglottis, suggesting its shape to be permanent. The cause of this misleading shape of the epiglottis in this patient is yet unknown. For similar cases, a possibility of this kind of epiglottis should be considered before diagnosing as acute epiglottitis.
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