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PubMed2006

A salt-free zero-charged aqueous onion-phase enhances the solubility of fullerene C60 in water.

An onion-phase (multilamellar vesicular phase or Lalpha-phase) was prepared from salt-free zero-charged cationic and anionic (catanionic) surfactant mixtures of tetradecyltrimethylammonium hydroxide (TTAOH)/lauric acid (LA)/H2O. The H+ and OH- counterions form water (TTAOH + LA --> TTAL + H2O), leaving the solution salt free. The onion-phase solution has novel properties including low conductivity, low osmotic pressure and unscreened electrostatic repulsions between cationic and anionic surfactants because of the absence of salt. The spherical multilamellar vesicles have an average 250 nm radius as measured by freeze-fracture transmission electron microscopy (FF-TEM) and the maximum interlayer distance, i.e., the thickness of the hydrophobic bilayer and the water layer, was calculated to be around 52 nm by small-angle X-ray scattering (SAXS). Extremely hydrophobic C60 fullerene can be solubilized in this salt-free zero-charged aqueous onion-phase. As a typical result, 0.588 mg.mL(-1) (approximately 0.82 mmol.L(-1)) C60 has been successfully solubilized into a 50 mmol.L(-1) catanionic surfactant onion-phase aqueous solution. The weight ratio of fullerene to TTAL is calculated to be around 1:40. Solubilization of C60 in the salt-free catanionic onion-phase solution was investigated by using different sample preparation routes, and a variety of techniques were used to characterize these vesicular systems with or without encapsulated C60. The onion-phase solution changed color from slightly bluish to yellow or brown after C60 was solubilized. 1H and 13C NMR measurements indicated that the C60 molecules are located in the hydrophobic layers, i.e., in the central positions [omega-CH3 and delta-(CH2)x] of the hydrophobic layers of the TTAL onion-phase. Salt-free zero-charged catanionic vesicular aqueous solutions are good candidates for enhancing the solubility of C60 in aqueous solutions and may broaden the functionality of fullerenes to new potential applications in biology, medicine, and materials. Hopefully, our method can also be extended to solubilize functionalized carbon nanotubes in aqueous solutions.

Fullerenes↗

PubMed2004

The repair of gamma-ray-induced chromosomal damage in human lymphocytes after exposure to extremely low frequency electromagnetic fields.

G(0) human blood lymphocytes were irradiated with 2.0 Gy gamma-rays and cultured to metaphase whilst held in a 50-Hz power frequency magnetic field of 0.23, 0.47 or 0.7 mT. No differences were found in the frequencies of gamma-induced chromosome aberrations observed in cells held in the EM fields compared with replicates held in a sham coil. Similar field conditions have been reported to increase the frequency of gamma-induced HPRT mutations, leading to a suggestion that the EM fields alter the fidelity of repair of genomic lesions. This was not confirmed by the chromosome aberration assay described here.

Adult↗

PubMed1977

Sclerosis of the intestinal tract with severe malabsorption.

The clinical findings and pathological changes in a 14 year old boy who died from severe malabsorption are presented. Early signs of the illness were attacks of abdominal pain, diarrhoea, and intermittent periods of constipation. Later, severe malabsorption together with chronic ileus were apparent but no organic obstruction was found at several laparotomies. X-ray examination revealed extremly distended intestinal loops and a very slow transit time of barium. Malnutrition could not be improved by dietary, medical, or surgical therapy. Microscopic examination of the tissues obtained at autopsy showed changes in the small vessels of the lungs, heart, kidneys, and intestine. Increased fibrous tissue combined with atrophy of the muscular coat was observed in the wall of the entire intestine. Although cutaneous changes of scleroderma were not evident the deposition of collagenous material and the vascular changes seem typical of systemic sclerosis.

Adolescent↗

PubMed2001

Metaphyseal fractures mimicking abuse during treatment for clubfoot.

BACKGROUND: Metaphyseal injuries resembling the classic metaphyseal lesion (CML) of abuse may occur as the result of serial casting during treatment of clubfoot deformity. Mentioned in the orthopedic literature in 1972, this iatrogenic fracture has not been described in the radiologic literature nor has the similarity to injuries occurring with abuse been previously recognized. OBJECTIVE: To describe the mechanism and radiographic appearance of metaphyseal injury observed during serial casting of clubfoot. Note similarities to the CML of abuse. MATERIALS AND METHODS: Eight children ranging in age from 1 to 4 months underwent casting for clubfoot. Five orthopedic surgeons from three different institutions performed the casting. Two patients had spina bifida and one, arthrogryposis. A complete skeletal survey was performed on one child who was abused; there was no suspicion of abuse in the remaining seven. RESULTS: All children manifest injury with periosteal new bone. One child had clear evidence of abuse with 24 rib fractures. X-rays of lower extremities in short leg casts revealed bilateral tibial metaphyseal fractures. Four other children had metaphyseal fractures resembling the CML of abuse, and three developed an area of sclerosis within the metaphysis. CONCLUSION: In the setting of serial casting for equinovarus deformity, metaphyseal injury even the CML of abuse may be noted. Since inflicted injuries are almost always unobserved and explanations rarely offered, the fact that the CML occurs as a result of orthopedic maniuplation may offer some further insight concerning the pathogenesis of this well-described abuse injury.

Casts, Surgical↗

PubMed2000

A case of postpregnancy osteoporosis.

A puerperant woman, who was previously healthy and had no disease known to affect bone metabolism, experienced lower back pain and lumbar vertebral fractures during lactation. Both bone formation markers and resorption markers were markedly elevated. Bone mineral density of the lumbar spine as measured by dual energy X-ray absorptiometry was extremely low. She stopped lactation through the use of bromocriptine because of the large volume of milk secretion. After treatment with calcitonin injections and the use of a corset, her back pain gradually disappeared. This case appears to be postpregnancy osteoporosis.

Absorptiometry, Photon↗

PubMed1999

Comment on the use of GOES solar proton data and spectra in solar proton dose calculations.

There is a need to understand the calibration and response of the GOES solar particle detectors since the GOES data are being used to evaluate high energy solar particle events. We share some of our experience in utilizing these data in the analysis of solar particle ground-level events (GLEs). For the 29 September 1989 event, we have evaluated the solar proton and alpha particle spectral characteristics throughout the event. The results show that the solar cosmic ray spectrum is extremely hard at low energies with the magnitude of the slope increasing with increasing energy and with time.

Alpha Particles↗

PubMed2006

Failed methotrexate termination of pregnancy: a case report.

We report a case of a fetus with shortened proximal long bones, ambiguous genitalia, intrauterine growth restriction and abnormal umbilical artery Doppler velocities observed on antenatal ultrasound exam. At 34 weeks the patient revealed methotrexate/misoprostol exposure at 6 weeks gestational age in attempted medical termination of pregnancy. On newborn exam, the baby had dysmorphic facial features, a short torso, scoliosis, a micropenis (phallus <1 cm) and shortened proximal long bones both upper and lower extremities. X-ray exam revealed a hemivertebra at T10 level, rib abnormalities, shortened proximal long bones, an absent pubic bone and bilateral knee ossification centers. With methotrexate exposure, improved counseling and surveillance could potentially avoid these significant abnormalities and prevent psychological distress.

Abnormalities, Multiple↗

PubMed1982

[Complications of treatment of neuroblastoma].

This article is based on two patients whose tumorous growths were successfully treated and who were cured of tumours and whose treatment had severe consequences. In one female patient, surgical removal of the tumour from the thoracic cavity resulted in haemorrhage into the spinal canal, leading to an irreversible transverse lesion of the cord with paraplegia. In the second patient, irradation with x-rays resulted in extremely severe radiation damage ultimately causing the death of the patient. Within the framework of this discussion, these problems are illuminated in detail. The emphasis is on severe damage in patients in whom the tumour itself has been cured in the course of the requisite therapeutic procedure. The author draws special attention to a stage-correlated treatment of neuroblastoma.

Child↗

PubMed2000

Determinants of bone density in healthy older men with low testosterone levels.

BACKGROUND: Osteoporosis is a significant problem in older men, 30% of all hip fractures occur in men and the mortality rate following hip fracture exceeds that of women. Testosterone is thought to be important in the development of peak bone mass hut its role in age-related bone loss is not established. The purpose of this study was to define the predictors of bone mass ill healthy older men with low testosterone levels but without symptomatic osteoporosis. METHODS: Eighty-three community-dwelling white men, aged more than 65 years old, selected for low bioavailable testosterone levels (< or = 4.44 nmol/l) participated in a cross-sectional study located at a university general clinical research center. Sex hormone concentrations and markers of bone turnover were assayed in serum and urine. Risk factors for osteoporosis and physical activity were ascertained by physical examination and questionnaire, including the Physical Activity Scale in the Elderly (PASE) questionnaire. Bone mineral densities of the femoral neck (FN BMD), spine, and whole body were measured by dual x-ray absorptiometry. Lower extremity muscle strength (1 repetition maximum) was measured using a leg press machine. RESULTS: Mean bone mineral density values were 0.93 +/- 0.14 g/cm2 for femoral neck, 1.31 +/- 0.23 g/cm2 for spine, and 1.22 +/- 0.12 g/cm2 for whole body. Thirty-one of the 82 subjects (37%) had t scores < -1 and 12 of 82 subjects (15%) had t scores < -2.5 at the femoral neck. Multiple linear regression analysis demonstrated that bioavailable testosterone, body mass index (BMI), and PASE scores were positively correlated with, and significant predictors of, femoral neck BMD, accounting for 34.4% of the variance in FN BMD (F = 10.10, p = .001). Examining each variable independently, bioavailable testosterone accounted for 20.7%, physical activity score for 9.0%, and BMI for 6.5% of FN BMD. Using analysis of variance, mean values for FN BMD were significantly different between men grouped by tertile of bioavailable testosterone (F = 6.192, p = .003). FN BMD mean values were 0.86 +/- 0.14 g/cm2 for the lowest tertile, 0.94 +/- 0.16 for the middle tertile, and 0.99 +/- 0.14 for the highest tertile. Markers of bone turnover were inversely correlated, and strength directly correlated with BMD, but did not contribute to the multiple regression model. CONCLUSIONS: Fifty-two percent of older men with low bioavailable testosterone levels had BMD levels below the young adult normal range and are likely at an increased risk of fracture. Bioavailable testosterone, BMI, and physical activity scores were significant determinants of FN BMD in these men. These variables are potentially modifiable and, therefore, amenable to intervention. Hence, our results suggest the need for testosterone replacement and physical activity intervention trials in men at risk for osteoporotic fractures.

Absorptiometry, Photon↗

PubMed1991

Extra-adrenal phaeochromocytoma presenting as fulminant malignant disease with tumour positive sputum cytology.

A case of a 69-year-old man with an extra-adrenal malignant phaeochromocytoma is described. Sputum cytology revealed metastatic cells, which have not been reported previously in malignant phaeochromocytoma. This case is also remarkable for the short duration of disease, rapid progression and extensive spread of metastases, the radiological aspect of metastatic lesions shown by chest X-ray, hypercalcaemia and extremely high levels of circulating catecholamines and urinary metabolites.

Aged↗

PubMed1998

Homologous recombination, but not DNA repair, is reduced in vertebrate cells deficient in RAD52.

Rad52 plays a pivotal role in double-strand break (DSB) repair and genetic recombination in Saccharomyces cerevisiae, where mutation of this gene leads to extreme X-ray sensitivity and defective recombination. Yeast Rad51 and Rad52 interact, as do their human homologues, which stimulates Rad51-mediated DNA strand exchange in vitro, suggesting that Rad51 and Rad52 act cooperatively. To define the role of Rad52 in vertebrates, we generated RAD52(-/-) mutants of the chicken B-cell line DT40. Surprisingly, RAD52(-/-) cells were not hypersensitive to DNA damages induced by gamma-irradiation, methyl methanesulfonate, or cis-platinum(II)diammine dichloride (cisplatin). Intrachromosomal recombination, measured by immunoglobulin gene conversion, and radiation-induced Rad51 nuclear focus formation, which is a putative intermediate step during recombinational repair, occurred as frequently in RAD52(-/-) cells as in wild-type cells. Targeted integration frequencies, however, were consistently reduced in RAD52(-/-) cells, showing a clear role for Rad52 in genetic recombination. These findings reveal striking differences between S. cerevisiae and vertebrates in the functions of RAD51 and RAD52.

Animals↗

PubMed2003

Optimized staircase profiles for diffractive optical devices made from absorbing materials.

We report on the optimization of staircase grating profiles for the case of absorbing grating materials. Using a simple numerical algorithm, we determined the grating parameters, maximizing the first-order diffraction efficiency for different numbers of staircase steps. The results show that there is a significant difference between the staircase profiles for nonnegligible and negligible absorption. The obtained solutions are of importance for diffractive optics in the soft-x-ray and extreme-ultraviolet ranges.

Journal Article↗

PubMed1997

[Analysis of high frequency X-ray images in 43 cases of breast cancer].

OBJECTIVE: To analyse a series of breast cancer images in high frequency X-ray for more accurate diagnosis of breast cancer. METHODS: Forty three high frequency X-ray images of breast cancer surgically confirmed were comprehensively analyzed. RESULTS: Of the 43 breast cancer cases, 42 were primary breast cancers and one secondary. Tumor mass was present in 38 cases, with burrs in 26. Malignant calcification was found in 13 cases, and structural derangement in 21 cases. There were 30 cases with abnormal blood vessels, and 7 cases with thick skins. Ductal and lymph drainage features were seen in 9 cases. There were 5 cases showing ox horn sign. The high frequency X-ray diagnosis of breast cancer conformed with pathologic diagnosis in 95.6% of the cases. CONCLUSION: The advantages of high frequency X-ray are its extremely high clarity and good contrast. Pictures can be taken form various axises which help detect occult and tiny cancer.

Adenocarcinoma↗

PubMed1963

Estimates of radiation doses in space on the basis of current data.

A gross survey of data on Van Allen belt radiations, galactic cosmic radiation, and solar cosmic radiation is presented. On the basis of these data that are, in part, fragmentary and uncertain, upper and lower limits of rad doses under different amounts of mass shielding are estimated. The estimates are preliminary especially in the cases of chance encounter with solar flare protons. Generally, the relative biological effectiveness of the high energetic space radiations and their secondaries appear insufficiently known to give detailed biological or rem doses. The overall ionization dosage of the low level galactic cosmic radiation in free space is estimated to be even in solar minimum years equivalent to less than 50 rem/year or 1 rem/week. Mass shielding up to 80 g/cm2 would not reduce the ionization dosage but would shield against heavy primaries and heavy ionizing secondaries, thus reducing the biological dose. The flux of energetic protons in the maximum intensity zone of the inner Van Allen belt is by about four orders of magnitude higher, their energy and penetration power, of course, lower. A shield of 25 g/cm2 would reduce the dose rate from 20 rad/hour under 2 g/cm2 to 5 rad/hour. These proton dose rates and also the electron and X-radiation dose rates under some g/cm2 shielding of low z-number material will not constitute a radiation hazard for flights straight through the inner and outer belt in about two hours. Staying within the maximum of the inner belt for two days would, however, lead even within 25 g/cm2 depth of outer shield and body itself to a dose of 200 rad which is on the permissible limit. Extreme solar cosmic ray events or proton showers of high intensity and a duration of days occurred with a frequency of 1-4 per year during the last highly active cycle. For the penetrating, most intense high energy event of February 23, 1956, the dose within 25 g/cm2 is estimated to have been in the order of 50 rad. In most cases the dose decreased more rapidly with penetration depth and would have been even in multiple events with such high shielding below critical levels, especially on inner organs. On the surface of the body and in a lightly shielded space vehicle or protected by a space suit only the dose can, especially in multiple events, reach values of 1000 rad and more.

Atmosphere↗

PubMed2003

[Embryonic rhabdomyosarcoma of the prostate. Report of a case and review of the literature].

OBJECTIVES: To report a new case of prostatic rhabdomyosarcoma in a child. METHODS: Blood analysis, urinalysis, radiologic tests (abdominal ultrasound, intravenous urography, cystography, barium enema, lower extremities X-rays), and prostatic biopsy were performed. RESULTS/CONCLUSIONS: Neoadjuvant treatment with chemotherapy and radiotherapy were started prior to intended radical prostatectomy, but the patient died before due to disease progression with dissemination.

Adolescent↗

PubMed1989

[A case report of quadriparesis due to compression of the medulla oblongata by the elongated left vertebral artery].

A patient, 30-year-old man, was admitted to Shinshu University Hospital with gait disturbance and numbness of both arms and legs in June 1985. General physical findings were normal except for facial asymmetry, i.e. mild right facial hemiatrophy. Blood pressure was normal and there were no signs of arteriosclerosis. Neurological examination revealed marked bilateral pyramidal tract signs, muscular weakness of all extremities predominant of the right side, spastic gait and sensory disturbance with impairment of pin prick and light touch sensation in the second and third trigeminal nerve regions and extremities of the left side, and mild loss of vibratory sense and numbness in all extremities. X-ray examination of the cervical spine and the myelogram of the spinal canal were normal. CT scan of the brain performed 3 hours after the myelography showed that the left vertebral artery extended from the left side of the medulla oblongata to the midline and distorted it by compression. MRI confirmed the findings of the CT scan. Vertebral angiography disclosed that the elongated left vertebral artery crossed the ventral aspect of the medulla oblongata. Compression of the medulla oblongata by the vertebral artery was diagnosed and neurovascular decompression was performed. About one month after the operation his spastic gait and muscular weakness were slightly improved, but these symptoms progressed thereafter. One year after operation his spastic gait was more marked than preoperatively. In many cases with dolichoectatic intracranial arteries, hypertension and arteriosclerosis have been reported to be usually associated with this condition. In other opinions dolichoectasia has been suggested to be a congenital disease, because such vessels are occasionally present in children.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1985

DNA polymerase I is crucial for the repair of potentially lethal damage caused by the indirect effects of X irradiation in Escherichia coli.

The radiosensitivity of an Escherichia coli mutant deficient in DNA polymerase I was measured in the presence of OH radical scavengers. The extreme X-ray sensitivity of the mutant could be abolished by OH radical scavengers if a sufficiently high level of radioprotector was present. There was a direct correlation between the OH radical scavenging activity of the chemicals tested (NO2-, n-butanol, glycerol, t-amyl alcohol, and t-butanol) and their protective ability. I interpret the data as showing that the indirect actions of X rays (primarily OH radicals) result in major damage to the bacterial DNA which in large part consists of potentially lethal lesions. This potentially lethal damage is repaired through an enzymatic pathway requiring DNA polymerase I. In the mutant lacking DNA polymerase I, these potentially lethal lesions are expressed as cell lethality.

1-Butanol↗

PubMed1982

[Congenital angiodysplasias of types F.P. Weber, Klippel-Trénaunay and Servelle-Martorell].

Basing our observations on a study of 47 cases of angiodysplasia of types F.P. Weber, Klippel-Trénaunay and Servelle-Martorell, we attempted to demonstrate that differentiation of these 3 syndromes is possible if criteria obtained from a non-invasive investigative method are used. This involves taking standard X-rays of the extremities (both sides) which are examined under direct magnification (0.1-01 mm) thus allowing the most exact possible analysis of the skeletal changes. In this way, the Weber syndrome should be suspected if bone prolongation is seen in association with loss of substances from the skeleton. In the Klippel-Trénaunay syndrome, the bone lengthening is not accompanied by bony lesions. In the Servelle-Martorell syndrome bony lesions go hand in hand with limb hypertrophy.

Angiomatosis↗