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At least 145 records · Page 8Linked to original sources
PubMed1995

Hand and wrist disorders: how to manage pain and improve function.

Pain, swelling, or impaired function of the hand or wrist may be the result of one of several chronic or acute conditions, including tendinitis, arthritis, infection, or trauma. The first step in diagnosing a hand or wrist disorder is a detailed history. Include a review of the medical history, as many systemic disorders (eg, psoriasis, diabetes mellitus, rheumatoid arthritis, and scleroderma) may affect the hand and wrist. In the physical exam, assess motions of the cervical spine and those of all joints in the symptomatic extremity. A simple neurologic evaluation is required to assess function of the major nerves in the upper extremity. X-rays are indicated in any patient with hand or wrist pain.

Aged↗
PubMed1984

Ulnar ray deficiency: its various manifestations.

Eighty-eight upper extremities of 65 patients with ulnar ray deficiency were reviewed with regard to clinical manifestations. Based on the findings, a subclassification into four types was established: type I, hypoplasia or partial defect of the ulna; type II, total defect of the ulna; type III, total or partial defect of the ulna with humeroradial synostosis; and type IV, ulnar defect with congenital amputation at the wrist. Various manifestations of deficiency were evident not only within the ulnar ray but also in other rays. Hypoplasia of the shoulder and/or proximal part of the humerus was present in some cases of types III and IV. Elbow involvement varied from functioning (type I) to acute flexion contracture (type II) to fusion (type III). In 57 hands the digits and carpal bones in the radial ray showed hypoplasia and/or defect. Central digits and carpal bones were also influenced by ulnar ray deficiency, presenting carpal bone fusion, syndactyly, and delta phalanx.

Abnormalities, Multiple↗
PubMed2000

Analysis of the hierarchical structure of biological tissues by scanning X-ray scattering using a micro-beam.

The outstanding mechanical properties of biological tissues such as wood or bone are mainly due to their hierarchical structure and to their optimization at all levels of hierarchy. It is therefore essential to characterize the structure at all levels to understand the complex behavior of such tissues. Structures down to the micrometer level are accessible to light or scanning electron microscopic observation. In the case of bone this includes, for example, morphometry of the trabecular architecture or the bone mineral density distribution in cortical and trabecular bone. To characterize the sub-micrometer structure of, e.g., the collagen-mineral composite in the case of bone or the cellulose microfibrils in the case of wood, other methods, such as transmission electron microscopy or X-ray scattering are necessary. The recent availability of extremely brilliant synchrotron X-ray sources has led to the development of the new techniques of scanning small-angle X-ray scattering and scanning X-ray microdiffraction, which are capable of providing structural information on the micrometer and the nanometer level, simultaneously. As a basic principle of the method the specimen is scanned across an X-ray beam which has a diameter of few micrometers. Measuring the X-ray absorption at each position provides an image of the specimen (microradiography) with resolution similar to light microscopy, in the micrometer range. Moreover, the X-ray scattering pattern is analyzed at each specimen position to provide parameters characterizing the structure in the nanometer range. The present paper reviews the principles of the techniques and demonstrates their application to biological materials, such as wood or bone.

Biomechanical Phenomena↗
PubMed2005

Type 0 ulnar longitudinal deficiency.

PURPOSE: To describe the characteristics of type 0 ulnar longitudinal deficiency (ULD) in which deficiencies are present in the hand and carpus without involvement of the forearm or elbow. METHODS: A retrospective chart, radiograph, and clinical photograph review (1960-2005) of patients previously diagnosed with ectrodactyly, hand hypoplasia, or ULD was performed to evaluate for a diagnosis of ULD isolated to the hand. RESULTS: Thirteen extremities were identified. Three extremities had complete absence of the small-finger ray (phalanges and metacarpal) and 6 extremities had complete absence of the ring- and small-finger rays. Four hands showed hypoplasia of the small finger, 3 in conjunction with a ring- and small-metacarpal synostosis and 1 in isolation. Three extremities also had radial-sided hypoplasia or aplasia of the rays. Additional common findings included simple syndactyly, delta phalanx, and carpal fusions, most commonly of the capitohamate joint. CONCLUSIONS: Patients with isolated ulnar-sided hand deficiency such as ectrodactyly of the ring and/or small fingers or synostosis of the small metacarpal of the ring finger in the presence of a normal forearm may be diagnosed as having type 0 ULD. We propose that type 0 be added to the current classification systems for ULD representing those extremities with deficiencies isolated to the hand.

Female↗
PubMed1998

Observation of the strain field near the Si(111) 7 x 7 surface with a new X-ray diffraction technique.

A new X-ray diffraction technique has been developed in order to measure the strain field near a solid surface under ultrahigh vacuum (UHV) conditions. The X-ray optics use an extremely asymmetric Bragg-case bulk reflection. The glancing angle of the X-rays can be set near the critical angle of total reflection by tuning the X-ray energy. Using this technique, rocking curves for Si surfaces with different surface structures, i.e. a native oxide surface, a slightly oxide surface and an Si(111) 7 x 7 surface, were measured. It was found that the widths of the rocking curves depend on the surface structures. This technique is efficient in distinguishing the strain field corresponding to each surface structure.

Journal Article↗
PubMed1979

Reparable and irreparable damage in yeast cells induced by sparsely ionizing radiation.

It is shown that in diploid yeast there are significant differences in the extent of irreparable damage after irradiation with X-rays, 60Co-gamma-rays and 30 MeV electrons. At extremely low dose rates, 60Co-gamma-rays were found to produce almost no irreparable damage at least up to 1200 Gy. X-rays, however, at the same low dose rate caused irreparable damage in the same dose range yielding a surviving fraction of 0.25 at 1200 Gy. For irradiations at high dose rate followed by liquid holding recovery the relative biological effectiveness of X-rays amounted to at least 4 for absorbed doses of up to 1000 Gy. With 30 MeV electrons at high dose rates an accumulation of sublethal and potentially lethal damage resulting in irreparable damage occurred above 1000 Gy. It is suggested that irreparable damage in yeast is due to a cooperative effect of neighbouring track ends.

DNA Repair↗
PubMedDate not supplied

[The clinical x-ray characteristics of the soft tissues of the lower extremities in diabetics].

The authors present the results of clinicoroentgenological and immunological investigations of the state of lower limb soft tissues in 117 patients with diabetes mellitus. Vascular wall calcification and soft tissue edema were noted practically in all the patients with a period of disease over 1 year. X-ray investigation permitted the detection of vascular lesion at early stages of complication development, in most of the patients even at the preclinical stage. A degree of lower limb vascular lesion is not related to a type of diabetes mellitus and the patients' age. There is direct correlation between the affection of the walls of medium size vessels and vessels of the fundus of the eye. The frequency and severity of lower limb vascular lesion, polyneuropathy and nephropathy grow significantly with an increase in a period of disease. A parallel decrease of immunoglobulins is noted. The affection of osseous tissue does not depend on a period of disease and shows insignificant correlation with a degree of vascular lesion.

Adolescent↗
PubMedDate not supplied

[Effects of low-intensity electromagnetic radiation of extremely high frequency on the animal body within the framework of total low-dose x-ray irradiation].

Effect of low-intensive electromagnetic radiation of extremely high frequency (EMR EHF) on the rats, subjected to the low-dose X-ray irradiation (6.192 mC/rg) was investigated. Content of glial fibrillary acidic protein as well as glucose content and activity of glutamate dehydrogenase and malate dehydrogenase was studied. It was shown than EMR EHF modifies the X-ray irradiation effect: filament GFAP concentration in brain and glucose content in serum were restored. The authors suggest central nervous system participation in realization of EMR EHF effects on the organism.

Animals↗
PubMed1981

Analytical scanning electron microscopy and x-ray microdiffractometry of renal calculi using etched plastic sections.

We describe the technique and illustrate results of renal calculi analyses utilizing correlative analytical scanning electron microscopy and x-ray microdiffractometry on the same 100 micrometer Spurr embedded sections. Essential to the technique is the employment of an extremely sensitive x-ray microdiffractometer, and for morphological analysis, pretreatment of the sections with a sodium ethoxide etching solution. This technique facilitates more precise identification of crystalline constituents especially calcium apatite and magnesium ammonium phosphate hexahydrate (struvite). Further, the technique permits detection and mapping of both crystalline and amorphous constituents within calculi.

Calcium Oxalate↗
PubMed2003

Synchrotron techniques for metalloproteins and human disease in post genome era.

Metalloproteins make up some 30% of proteins in known genomes. Metalloproteins are a special class of proteins that utilise the unique properties of metal atoms in conjunction with the macromolecular assembly to perform life-sustaining processes. A number of metalloproteins are known to be involved in many disease states including ageing processes. The incorporation of the metal ion is a very tightly regulated process that, in vivo, very often requires specific chaperones to deliver and help incorporate the metal atom in the macromolecule. The lack of or inappropriate incorporation of metals along with genetic factors can lead to the mis-function of these proteins leading to disease. The mis-functions due to genetic alterations that lead to diseases like ALS (amyotrophic lateral sclerosis or motor neuron disease) and Creutzfeld Jacob disease (CJD) are now well recognised. Synchrotron radiation sources provide a unique set of structural tools, which in combination can prove extremely powerful in providing a comprehensive picture of these complex biological systems. In particular for metalloproteins, the combined use of X-ray crystallography, X-ray solution scattering and X-ray spectroscopy (XAFS) is extremely useful. We are currently engaged in a structural study where our aim is to characterize structurally and functionally metalloproteins and then transfer this knowledge to afford the problem of the mis-function of metalloproteins that lead to these terminal illnesses, either due to a gain of function/property or a loss of function/property. In this context, the benefits of adopting the 'philosophy' being developed for the structural genomics effort are highlighted.

Amyotrophic Lateral Sclerosis↗
PubMed1999

Long-term exposure to a magnetic field (5 mT at 60 Hz) increases X-ray-induced mutations.

Exposure to extremely low frequency magnetic field (ELFMF) at 400 mT has been shown to induce mutations (Mutat. Res., 349: 109-114, 1996; Int. J. Radiat. Biol., 71: 75-79, 1997; and Biochem. Biophys. Res. Commun., 243: 579-584, 1998). However, whether ELFMF at low flux densities (under 1 mT) induces mutations is debatable. We investigated the effect of long-term exposure to 5 mT ELFMF at 60 Hz on mutant frequency. Chinese hamster ovary K1 (CHO-K1) cells were exposed or sham-exposed to 5 mT ELFMF for up to 6 weeks with or without X-irradiation (3 Gy), and the mutant frequency of the hypoxanthine-guanine phosphoribosyl transferase (HPRT) gene was analyzed. Long-term exposure to 5 mT ELFMF did not increase mutations, suggesting a threshold for mutation induction greater than 115 mA/m2 or a magnetic density of 5 mT. However, enhancement of the X-ray-induced mutation rate was observed after treatment with X-irradiation followed by long-term exposure to 5 mT ELFMF. At little as a 1-week exposure to ELFMF after X-irradiation enhanced the mutation rate. We also found that 400 mT exposure enhanced the mutation rate induced by X-irradiation (Mutat. Res., 349: 109-114, 1996). These results suggest that exposure to more than 5 mT ELFMF may promote X-ray-induced mutations.

Animals↗
PubMed1981

[Indications for surgery in ruptures of ankle joint ligaments (author's transl)].

X-ray films of the forced extreme joint position are required for diagnosis of lateral ligamentous injuries of the ankle joint. These x-ray films must be taken in forced extreme joint position in two planes (a.p. and lateral planes) by means of a special holding device simulating the mechanism of trauma by supination, inversion and adduction of the ankle joint by plantar flexion of the foot. If there is a 5 degree difference in talar tilt angle or a 5 mm difference in talar subluxation, an operation is indicated to prevent post-traumatic weak ankle and early arthrosis following chronic instability.

Adult↗