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At least 181 records · Page 10Linked to original sources
PubMed2005

Six-week improvements in muscle mass and strength during androgen therapy in older men.

BACKGROUND: The purpose of our study was to assess the early effects of a potent anabolic androgen on muscle mass and strength, lower extremity power, and functional performance in older men. METHODS: Thirty-two men 72 +/- 6 years of age were randomized to receive oxandrolone (10 mg twice daily) or matching placebo in a 2:1 manner for 12 weeks. Total and appendicular lean body mass (LBM) were assessed by dual-energy x-ray absorptiometry (DEXA). Lower extremity muscle volume was determined by magnetic resonance imaging to validate DEXA changes. RESULTS: Total LBM increased by 2.7 +/- 1.6 kg after 6 weeks with oxandrolone (p <.001), which was greater (p <.001) than the decline in LBM (-0.5 +/- 0.9 kg) with placebo. Appendicular LBM increased by 1.2 +/- 0.9 kg after just 6 weeks with oxandrolone (p <.001), which was greater (p <.001) than the decline in LBM (-0.4 +/- 0.5 kg) with placebo. These changes were >90% of the gains in total and appendicular LBM (3.0 +/- 1.5 kg and 1.3 +/- 0.9 kg, respectively) after 12 weeks. Total thigh and hamstring muscle volume increased by 111 +/- 29 mm(3) (p =.001) and 75 +/- 18 mm(3) (p =.001), respectively, after 12 weeks. Maximal strength increased for the leg press 6.3 +/- 5.6% (p =.003), leg curl 6.7 +/- 8.6% (p =.01), chest press 6.9 +/- 6.5% (p =.001), and latissimus pull-down 4.8 +/- 6.3% (p =.009) with oxandrolone after 6 weeks; these increases were different than those with placebo (p <.001) and were 93%, 96%, 74%, and 94% of the respective gains at week 12. There were no improvements in functional measures. CONCLUSION: Treatment with a potent anabolic androgen may produce significant increases in muscle mass and strength after only 6 weeks in healthy older men. However, such treatment did not improve leg muscle power or walking speed.

Aged↗
PubMedDate not supplied

[Healing of "wire tunnels" in tibial diaphysis: data of local X-ray study and densitometry].

Fifteen pelvic extremities from adult dogs were used to perform 60 cross tunnelization of tibial diaphysis with a wire having a pointed groove, 1.8-mm in diameter, at 1,500 rpm. Thirty five leg X-ray films in the lateral projection, which show changes on days 30, 60, 90, 120, 520 after the experiment, were studied. Bony diaphysis tunnelization was found to give rise to a regeneration focus wherein an area of tissue element degradation and an area of introduction of bony fragments into soft tissues were detectable. Changes in the regeneration focus were determined by a response to osseous fragments, which involved the formation of an bony regenerate during a month and to the resorption of the bony matter of an osseous regenerate and osseous fragments in future. Healing of diaphysis defects began with the resorption of a damaged cortical layer. Osteogenesis prevailed at month 2 and ensured healing of cortical layer defects following 4-6 months.

Absorptiometry, Photon↗
PubMed2005

[Silica-containing urinary stones--clinical issues to keep in mind].

Formation of calculi in efferent urinary passages is always due to supersaturation of urinary calculi substances and associated increased crystallization. Apart from the typical calculi, consisting of calcium oxalate, inorganic phosphates, uric acid or cystine, there are occasional signs of rare substance classes. Although more than 50 silicate stones have already been reported internationally, this stone entity remains relatively unknown. In particular, the occurrence of silicate stones in the absence of magnesium trisilicate abuse is extremely rare. A medium-sized left-sided ureterolith was removed from a 54-year-old male patient using a ureteroscope. X-ray diffraction showed it to be a compound stone consisting of 40% silicate. The patient, who in 1986 was living close to the nuclear reactor accident in Chernobyl, showed no signs of a constant uptake of magnesium trisilicate. However, he had undergone partial (2/3) gastrectomy 4 months before for a drug-refractory gastric ulcer, which had been diagnosed at the end of the 1980s and treated with excessive dosages of a magnesium trisilicate antacid preparation until the time of the operation. The patient had also been suffering from unstable angina pectoris since 1986 and treated with Pentalong (pentaerythrityltetranitrate) for 17 years. We were also able to detect silicium dioxide in components of this drug using X-ray diffraction. Silicate uroliths are extremely rare but they can be clearly identified by X-ray diffraction or infrared spectroscopy and distinguished from artifacts or quartz pebbles. Formation of calculi can be prevented by increasing diuresis as well as switching to a different drug and reducing the dosage.

Angina, Unstable↗
PubMed1997

[Delayed exacerbation of cervical myelopathy in a case of juvenile muscular atrophy of unilateral distal upper extremity].

We reported a case in which cervical myelopathy exacerbated 20 years after the stabilization of juvenile muscular atrophy of unilateral distal upper extremity. The patient presented progressive weakness in the right proximal upper extremity and spastic paraparesis in addition to the long-lasting muscular atrophy of right distal upper extremity. Plain x-ray showed severe cervical spondylosis with kyphosis of the cervical spine. Dynamic study on MRI disclosed cervical spinal cord atrophy and compression enhanced in both flexion and extension position of the neck. Malalignment (kyphosis) and severe spondylotic change of the cervical spine seemed to affect the spinal cord with little functional reservoir, manifesting the delayed exacerbation of myelopathy. We conclude that malalignment and subsequent spondylotic change of the cervical spine would be significant factors to determine the long term prognosis of patients with juvenile muscular atrophy of unilateral distal upper extremity.

Arm↗
PubMed2001

Recovery from severe glucocorticoid-induced osteoporosis in an adolescent boy.

An 18-yr-old boy presented with extreme back pain as the result of multiple vertebral fractures. At age 16 he had developed a tumor of the mesencephalon. A ventriculoperitoneal shunt was established surgically. One year later, he developed progressive neurologic deficits in his upper and lower limbs with an increase in the size of the tumor. He was treated by irradiation and high doses of glucocorticoids. Although the neurologic deficits progressively improved, he developed severe back pain resulting in complete immobilization for 3 mo in spite of neurologic recovery. Multiple vertebral fractures were diagnosed by X-ray. Bone density was extremely low (Z-score of -5.5 in the spine and -3.1 in the femoral neck). The patient was treated with calcium and vitamin D, calcitonin, bisphosphonates, physiotherapy, and progressive mobilization. Glucocorticoids were decreased and could be stopped as the neurologic deficits fully recovered. After 1 yr of treatment with intermittent i.v. pamidronate, bone density had increased by 40% in the spine and by 25% in the femoral neck despite growth arrest. He progressively recovered from back pain and is now, at age 20, fully ambulant, studying mechanical engineering, without neurologic sequelaes and free of glucocorticoids. Magnetic resonance imaging revealed that the tumor had disappeared. This case proves that treatment of symptomatic glucocorticoid-induced osteoporosis during puberty can be rewarding, even when multiple and invalidating vertebral fractures already exist.

Adolescent↗
PubMedDate not supplied

[Clinical and X-ray diagnosis of vertical blood reflux in muscle-venous pump of lower extremities and pelvis in varicosity].

Four hundred and twenty three patients with varicosity were comprehensively examined and surgically treated. X-ray diagnosis of vertical blood reflux was made in each of 4 musculovenous pumps (the abdominocaval pump, the punps of the hip, shin, foot). The first pump was studied by retrograde pelvic phlebography through the contralateral leg, the second one was examined by retrograde contrast administration into the onset of the external iliac vein as the second stage of retrograde pelvic phlebography or by its direct puncture, the third pump was explored by retrograde saphenous phlebography with pneumocompression of deep veins of the hip proximalo the site of puncture. The vertical reflux in the foot pump was determined by retrograde talocrural phlebography by contrast administration into the accompanying rectal vein above 4 cm of the foot along the Lington line. At surgery, vertical blood reflux was removed in each area of the musculovenous pump by extravasal correction of failing deep venous valves. Analyzing the outcomes of treatment in the patients and controls who underwent routine superficial and accompanying vein surgery without removing vertical blood reflux showed that the application of the new approaches to X-ray diagnosis and treatment of varicosity yielded excellent and good treatment outcomes by 10.6%, reduced poor ones by 10.8%, shortened the mean disability duration by 15.6 + 2.3 days, prevented disability.

Adolescent↗
PubMed1995

Use of X-rays in family practice. A multicentre study.

Practicing physicians, faced with pressure to control health care costs, are increasingly being asked to incorporate considerations of cost into their decisions regarding the care they offer their patients. Accordingly, it is of importance to know how the money is spent. The use and cost of X-rays in family practice, and what factors influence it, is not well known. The aim of this study is to analyse the use and the cost of X-ray requests in family practice. A prospective practice study from 16 Icelandic community health centres (HC) with computerised contact data and their target populations, 12 rural and four urban, was carried out. The X-ray requests, numbers, types and cost were analysed. Patient and practice characteristics were used to assess variation in X-ray practices. A total of 5173 X-ray requests were recorded, which comprised 3.2% of all office visits. The mean number of X-ray requests was 24.7 and 14.7/1000 contacts in rural and urban HCs respectively, and 123.1/1000 inhabitants in rural HCs. The X-ray request rate per individual increased with age, but per contact it was highest among young males. Extremity and chest X-rays were the most common requests. For every 1000 individuals added to a practice population, the likelihood of having an X-ray requested decreased by 18%. The use of X-ray examinations in family practices represents approximately 17% of all ambulatory X-ray use in Iceland. The calculated cost of X-rays requested in this study was $6157/1000 inhabitants per year as of October 1993.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

[Dumbbell cervical neurinomas with subcutaneous extension: report of two cases].

Two cases of dumbbell cervical neurinomas with massive subcutaneous extension were reported. The first case was A 30-year-old woman who was admitted to our hospital because she had been aware of a left lateral cervical subcutaneous mass and was suffering from shoulder dullness. On admission, neurological examination revealed hypesthesia to touch and pain in the segmental area of C4, and hyperreflexia in the left biceps and patellar tendon reflexes. Plain X-ray showed enlargement of the left C3/4 intervertebral foramen. CT scan, post-myelogram CT and MRI demonstrated a dumbbell shaped tumor at the level of C3-4. Angiogram showed an anterior shift of the left vertebral artery (VA) and tumor stain. Temporary occlusion of the left VA by a balloon catheter was performed leaving no neurological deficits. The second case was a 36-year-old woman who had been aware of a left lateral cervical subcutaneous mass. She complained of shoulder pain and finger clumsiness. On admission, neurological examination revealed weakness of the left deltoid muscle, hypesthesia in the segmental area of C3-4 and exaggeration of all deep tendon reflexes in the left-side extremities. Plain X-ray showed enlargement of the C2/3, C3/4 and C4/5 intervertebral foramina. CT scan, post myelogram CT and MRI demonstrated a dumbbell shaped tumor at the level of C2-5. Angiogram showed an anteromedial shift of the left VA and tumor stain. Temporary occlusion test of the left VA by a balloon catheter was performed with negative results. In each case two-stage operations were undertaken with excellent results.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2003

Induction of kinetochore-positive and kinetochore-negative micronuclei in CHO cells by ELF magnetic fields and/or X-rays.

To test the genotoxic effects of extremely low frequency (ELF) magnetic fields, the induction of micronuclei by exposure to ELF magnetic fields and/or X-rays was investigated in cultured Chinese hamster ovary (CHO) cells, using the cytokinesis block method. Micronuclei derived from acentric fragments or from whole chromosomes were evaluated by immunofluorescent staining using anti-kinetochore antibodies from the serum of scleroderma (CREST syndrome) patients. A 60 Hz ELF magnetic field at 5 mT field strength was applied, either before or after 1 Gy X-ray irradiation or without additional X-ray irradiation. No statistically significant difference in the frequency of micronuclei in CHO cells was observed between a sham exposure (no exposure to an ELF magnetic field) and a 24 h ELF magnetic field exposure. Exposure to an ELF magnetic field for 24 h before X-ray irradiation or for 18 h after X-ray irradiation did not affect the frequency of X-ray-induced micronuclei. However, the number of kinetochore-positive micronuclei was significantly increased in the cells subjected to X-ray irradiation followed by ELF magnetic field exposure, but not in the cells treated with ELF magnetic field exposure before X-ray irradiation, compared with exposure to X-rays alone. The number of spontaneous kinetochore-positive and kinetochore-negative micronuclei was not affected by exposure to an ELF magnetic field alone. Our data suggest that exposure to an ELF magnetic field has no effect on the number of spontaneous and X-ray-induced micronuclei. However, ELF magnetic field exposure after but not before X-ray irradiation may somehow accelerate X-ray-induced lagging of whole chromosomes (or centric fragments) in CHO cells.

Animals↗
PubMed1984

Radiation-induced renal damage: the effects of hyperfractionation.

The response of mouse kidneys to multifraction irradiation was assessed using three nondestructive functional end points. A series of schedules was investigated giving 1, 2, 4, 8, 16, 32, or 64 equal X-ray doses, using doses per fraction in the range of 0.9 to 16 Gy. The overall treatment time was kept constant at 3 weeks. Kidney function was assessed from 19 to 48 weeks after irradiation by measuring changes in isotope clearance, urine output, and hematocrit. The degree of anemia (assessed from the hematocrit measurements) is a newly developed assay which is an early indicator of the extent of renal damage after irradiation. All three assays yielded steep dose-effect curves from which the repair capacity of kidney could be estimated by comparing the isoeffective doses in different schedules. There was a marked influence of fractionation, with increasing dose being required to achieve the same level of damage for increasing fraction number, even between 32 and 64 fractions. The data are well fitted by a linear quadratic dose-response equation, and analysis of the data in this way yields low values (approximately 3.0 Gy) for the ratio alpha/beta. This would suggest that hyperfractionation , using extremely small X-ray doses per fraction, would spare kidneys relative to tumors and acutely responding tissues.

Animals↗
PubMed1987

Neutron RBEs and the radiosensitive target for mouse immature oocyte killing.

The highly radiosensitive immature oocytes of mice were irradiated in vivo with graded doses of 252Cf fission radiation, 0.43- or 15-MeV neutrons, or 60Co gamma rays. Comparisons of oocyte survival for neutrons and for gamma rays demonstrate that neutron RBEs for the killing of these important cells do not reach the high values (30-50 or more) at low doses observed for several other biological end points. Rather, neutrons differ little in effectiveness from gamma rays in killing these extremely sensitive murine oocytes. For 0.43-MeV neutrons, RBEs obtained from fitted survival curves reach only 1.7 at 0.1 rad. For 15-MeV neutrons, they are not significantly different from 1 at any dose tested (lowest, 4.5 rad). For 252Cf fission neutrons (E = 2.15 MeV), RBEs are intermediate between those for 0.43- and 15-MeV neutrons. For all neutron energies tested, the RBEs are particularly low in the juvenile period, a time when murine immature oocytes are especially radiosensitive. With exposure just prior to birth, however, when these cells are much less easily killed, higher, more usual RBEs are found. The minimum size of the lethality target in mouse immature oocytes, estimated from the inactivation constant for 0.43-MeV neutrons and microdosimetric values, is larger than the nucleus but not larger than the cell. This and related analytical considerations suggest that the hypersensitive target in these particular oocytes is the plasma membrane, a finding which is in excellent accord with results from other experiments using different, contrasting radiations and dose deliveries (accelerated Si14+ ions, gamma rays, and beta rays from 3HOH compared with those from [3H]thymidine).

Animals↗
PubMed2004

Taking X-ray diffraction to the limit: macromolecular structures from femtosecond X-ray pulses and diffraction microscopy of cells with synchrotron radiation.

Recent work is extending the methodology of X-ray crystallography to the structure determination of noncrystalline specimens. The phase problem is solved using the oversampling method, which takes advantage of "continuous" diffraction patterns from noncrystalline specimens. Here we review the principle of this newly developed technique and discuss the ongoing experiments of imaging nonperiodic objects, such as cells and cellular structures, using coherent and bright X rays produced by third-generation synchrotron sources. In the longer run, the technique may be applicable to image single biomolecules using anticipated X-ray free electron lasers. Here, computer simulations have so far demonstrated two important steps: (a) by using an extremely intense femtosecond X-ray pulse, a diffraction pattern can be recorded from a macromolecule before radiation damage manifests itself; and (b) the phase information can be retrieved in an ab initio fashion from a set of calculated noisy diffraction patterns of single protein molecules.

Algorithms↗
PubMed1981

[Comparative examinations on diagnosis and therapy of fresh injuries of the exterior ligaments (author's transl)].

We are conducting a standardized investigation of injuries of the exterior ligaments, using X-ray films taken in forced extreme joint position in two planes. The advantage of this method is the comparison of the X-ray films taken while exerting a constant force. The X-ray films must be taken in two planes to permit a clear statement about the severity of the injury. It is necessary to exclude a hypermobile ankle joint by means of a comparative X-ray of the healthy limb. Adequate therapy with an elastic bandage, plaster cast or surgery based on this diagnostic method will ensure good results.

Adolescent↗
PubMed1993

Crystallization and preliminary X-ray analysis of an NAD(+)-dependent alcohol dehydrogenase from the extreme thermophilic archaebacterium Sulfolobus solfataricus.

An NAD(+)-dependent alcohol dehydrogenase from the extreme thermophilic archaebacterium Sulfolobus solfataricus has been crystallized in the holo-enzyme and apo-enzyme forms. Crystals of the holo-enzyme grow from 2-methyl-2,4-pentanediol at pH 8.4 with the addition of NADH and at pH 7.0 with the addition of NADH and dimethyl sulphoxide. Crystals of the apo-enzyme grow at pH 6.3 from a mixture of polyethylene glycol 4000 and propan-2-ol. The holo-enzyme crystallizes in C2 with a dimer in the asymmetric unit, however the crystals are twinned and unsuitable for data collection. The apo-enzyme crystallizes in I4(1)22 (a = 126.82 A, b = 118.95 A) with a monomer in the asymmetric unit, and the single crystals diffract to 2.8 A.

Alcohol Dehydrogenase↗
PubMed1990

Phocomelia and additional anomalies in two sisters.

Two daughters of non-consanguineous normal parents had phocomelia of both lower extremities with 4-toed feet. The older sister also had phocomelia of the left upper extremity with 5 finger rays; she died immediately after birth. Autopsy disclosed a congenital diaphragmatic hernia, common mesentery and agenesis of the gallbladder, and normal female genitalia. In addition, the younger sister showed a bony skull defect, diastasis recti, agenesis of the uterus and agenesis or atresia of the vagina, hypoplasia of the sacrum and hypo/dysplasia of the pelvic bones. Her growth and mental development were normal. The patterns of anomalies of the two sisters do not fit into any of the syndromes featuring phocomelia; there was no prenatal exposure to thalidomide or any other possible teratogen.

Abnormalities, Multiple↗
PubMed1991

Repair of damage caused by UV- and X-irradiation in the amoeboflagellate Naegleria gruberi.

Cysts of Naegleria gruberi have a normal UV- and an extremely high X-ray resistance compared to other protozoans. Caffeine and 3-aminobenzamide applied to excysting amoeba after irradiation in the encysted state (UV and X-rays) by feeding with drug-containing bacteria increased lethality, while fractionated irradiation (UV) and liquid-holding (UV and X-rays) increased survival. Illumination with visible light after UV-irradiation restored almost 100% viability. The results are discussed in regard to the activity of repair mechanisms.

Animals↗
PubMed1991

[Head posture in lateral roentgen image].

A cervico-cephalometric examination of 61 yet untreated orthodontic patients was performed in order to analyze differences in head posture between standardized cephalograms and lateral cephalograms taken in natural head position. Additional x-rays were taken in extreme flexion and extention of the head in 48 patients examining the mobility of the upper cervical spine. Finding partly large differences in cranio-vertical and cranio-cervical parameters between the two methods of registration it could be shown, that head posture on the average was more proclined in natural than in fixed standardized position. Subjects with class III malocclusion tended to a more extended head posture relatively to those with class I or class II malocclusion. Judging the atlas position with regard to the functional mobility of the upper cervical spine, a superior and inferior atlas position was not thought to be a pathologic fixed malposition.

Adolescent↗