Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0086543 (cataract)
 29,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previous observations of raised calcium content in mature senile cataract are confirmed in the present study. Also human hypocalcemic cataract showed increased amounts of calcium in accordance with previous observations in animals. On the other hand, the magnesium content of the lens was not influenced by cataract development. The calcium aqueous/serum ratio was similar in all examined groups (normal, hypocalcemic-, incipient-, and mature senile cataract), whereas the corresponding magnesium ratio was elevated in the cataract patients. This observation may indicate a possible connection between magnesium metabolism and the development of cataract.
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PMID:The calcium and magnesium content of the human lens and aqueous humour. A study in patients with hypocalcemic and senile cataract. 338 87

Hachimi-jio-gan (Rehmannia Eight Formula, pa-wei-ti-huang-wan or Bawei dihuang wan) is one of traditional Chinese medicines which has been used for treating various senile disease for a few hundred years. This drug was evaluated for its therapeutic efficacy to rat galactosemic cataract from the suppressive rate of variance of some biochemical parameters, whose variation with cataractogenesis or the advance of cataract have been reported already. The dose of 500mg of Hachimi-jio-gan/day/200g of rat body weight suppressed significantly the variations of hydration rate, Na/K ratios, and calcium ion level in the lens with the advance of galactosemic cataract, especially when the drug was administered by the pre- or concurrent-administration before or with 30% of galactose diet respectively. This drug also could delay the progressive rate of lens opacification. However, the drug had no effect to suppress the galactitol accumulation in the lens. From these results, we presume that a drug action of Hachimi-jio-gan may control the balance of sodium, potassium and calcium ions which are important in relation to the maintenance of lens transparency. Then, we realized, that this drug may have a prophylactic efficacy to diabetic cataract, though a more detail study should be needed to apply this drug to human cataract disease.
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PMID:The evaluation of therapeutic efficacy of hachimi-jio-gan (traditional Chinese medicine) to rat galactosemic cataract. 350 15

Twenty seven cases of actionomycotic mycetoma caused either by Actinomadura madurae or Actinomadura pelletierii have been described. Infection by A. madurae has been more common than A. pelletierii. Left foot in A. madurae and right foot in A. pelletierii infections were involved more commonly in adult males, whereas right foot of the females was frequently affected in A. madurae infection. Large, soft, white grains in A. madurae and small, firm, red grains in A. pelletierii were consistently seen. Deep hematoxylin stained grains with scalloped margin and prominent eosinophilic club in A. madurae and such deep stained grains with smooth margin and horizontal cracks appearing as portions of a spherical mass in A. pelletierri were diagnostic. Large numbers of plasma cells and Russel bodies were also characteristic of A. madurae infection. Both the grains were stainable with Von Kossa method for calcium. Bone changes were similar in both the infections. Oral tetracycline produced soft tissue and bone resolution to almost normalcy in those who regularly consumed the drug any time from 2 to 6 years. Mild glucose intolerance, facial hyperpigmentation and urticaria were the side effects observed in a few. Two patients developed cataract following tetracycline therapy. The value of medical therapy with oral tetracycline in Actionomadura mycetomas is emphasized.
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PMID:A clinico-pathological study of actinomycotic mycetomas caused by Actinomadura madurae and Actinomadura pelletierii. 357 38

Small angle neutron scattering (SANS) was used to compare two models of cataracts: the cold cataract induced in the lens nucleus cytoplasm by lowering the temperature and the opacification induced by calcium in the lens cortex cytoplasm. In both cases opacified cytoplasms display additional scattering at low angles as compared to their clear controls. An analysis of this additional scattering provides quantitative information concerning the size distribution, the number and contrast of the scatterers responsible for lens opacification. The scatterers of cold cataract and of calcium--induced opacification not only have, as shown elsewhere, a different composition but are also found to display completely different sizes (in the thousand A range for cold-cataract, in the hundred A range for calcium--induced opacification). These results illustrate the diversity of scatterer types which are able to cause comparable lens opacities.
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PMID:Neutron scattering by calf lens cytoplasm. A comparison between two models of cataract. 360 32

Opacification was induced in calf lens cytoplasmic extracts by addition of calcium. The sample turbidity was shown to increase with calcium molarity, incubation time and temperature and to decrease with the protein cytoplasmic concentration. Although this turbidity was enhanced when membrane fragments were left over in the cytoplasmic extracts, it did show up in the absence of any detectable vesicular fragment. Scattering techniques (X-ray and light) showed that the calcium-induced opacification is linked to enhanced light scattering, which results from the formation of additional scatterers, a few tens of nm in diameter. Additional structures were indeed visualized by freeze-fracture electron microscopy (FFEM): they appear as molecular clusters with diameters ranging from 20 to 90 nm, made of densely packed particles, with heterogeneous sizes. The turbidity expected from these clusters, as well as the expected variation of turbidity with cytoplasmic concentration, was calculated to be in agreement with the measurements. When compared with cold cataract, these results illustrate that similar opacities may result from completely different biophysical mechanisms.
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PMID:Effect of calcium on the calf lens cytoplasm. 362 43

The pathology of rainbow trout lenses incubated in various media and at various temperatures was examined by electron microscopy. After incubation at 0 degrees C for 5 h, no changes were observed in transparency and cytology. Irreversible warm cataract occurred at 37 degrees C, which corresponds to the body temperature of mammals. The degree of turbidity increased depending on incubation time. The ultrastructure of warm cataract in short-term incubation was characterized by the appearance of dense substances in the epithelium and swelling of the lens fibers. When the incubation time was prolonged up to 3 h, the turbidity increased and cellular disorders became severe. The volume of the dense substances increased also. A slight but detectable haziness of the lens was observed after incubation with calcium-free medium. Pathological findings in this case consisted of disorders of the intracellular membrane system in the epithelium and swelling of the lens fibers. These results suggest that the rainbow trout lens has a lower optimum temperature compared to the mammalian lens but requires the same Ca2+ concentration.
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PMID:Ultrastructural study of rainbow trout lenses incubated under various conditions. 374 50

Myotonic dystrophy (MyD) is a multisystemic disorder characterized by muscle weakness, myotonia, cataract and frontal baldness. Several endocrinological abnormalities are also known in this disorder. Although presence of bone changes, such as hyperostosis, has been frequently reported in MyD patients, there have been few published papers in which calcium metabolism was precisely examined. The present study was designed to elucidate the possibility of the presence of abnormal calcium metabolism in MyD by using the oral calcium tolerance test. Ten patients with MyD, 11 patients with other neuromuscular disorders (non-MyD) and 9 healthy control subjects were investigated according to the method of Broadus et al. Increments of serum and urinary calcium levels after oral calcium load (1 gram) were determined as indices of intestinal calcium absorption. There were no significant differences in basal plasma calcium and phosphate levels among the three groups. Plasma 1,25(OH)2D level in MyD (38.0 +/- 11.8 pg/ml, Mean +/- SD) was significantly higher than those in the other two groups (normal subjects 21.8 +/- 7.0; P less than 0.01, non-MyD 21.8 +/- 12.0; P less than 0.01), respectively. In contrast, plasma 25(OH)D and 24, 25(OH)2D levels were not significantly different among these groups. Fasting urinary calcium excretion in both MyD (0.151 +/- 0.069 mg/100 ml GF) and non-MyD (0.141 +/- 0.077) was significantly higher than that in normal subjects (0.064 +/- 0.048). Calcemic response in MyD (1.08 +/- 0.20 mg/dl) was significantly increased when compared with that in normal subjects (0.72 +/- 0.34, P less than 0.02) and non-MyD (0.54 +/- 0.31, P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Abnormal calcium metabolism in myotonic dystrophy: increased level of serum 1,25(OH)2D concentration and augmented intestinal calcium absorption]. 380 29

Secondary ion mass spectrometry (SIMS) is a surface analytical technique with high sensitivity for elemental detection and microlocalization capabilities within the micrometre range. Quantitative analysis of epoxy resins and gelatin have been reported (Burns-Bellhorn & File, 1979). We report here the first application of this technique to quantitative microlocalization in the context of a physiological problem--analyses of sodium, potassium and calcium in normal and galactose-induced cataract in rat lens. It is known that during the development of galactose-induced cataract the whole lens content of potassium is decreased, sodium is increased and, in late stages, calcium concentration increases. Whether these alterations in diffusible ions occur homogeneously or heterogeneously is not known. Standard curves were generated from epoxy resins containing known concentrations of sodium, potassium or calcium organometallic compounds using the Cameca IMS 300 Secondary Ion Mass Spectrometer. Normal and cataractous lenses were prepared by freezing in isopentane in a liquid nitrogen bath followed by freeze-drying at -30 degrees C. After dry embedding in epoxy resin, 10 microns thick sections of lens were pressure mounted on silicon wafers, overcoated with gold, and ion emission measured under the same instrumental conditions used to obtain the standard curves. Quantitative analysis of an area 27 microns in diameter, or a total analysed volume of 1.1 microns3, was performed by using a mechanical aperture in the ion optical system. Ion images provided qualitative microanalysis with a lateral resolution of 1 micron. Control rat lenses gave values for sodium and potassium content with a precision of +/- 17% or less. These values were compared to flame photometry and atomic absorption measurements of normal lenses and were accurate within 25%. Analysis of serum and blood also gave accurate and precise measurements of these elements. Normal rat lenses had a gradient of sodium, and, to a lesser degree, of potassium from the cortex to the nucleus. Development of galactose-induced cataract was heterogeneous by morphological criteria, beginning at the lens equator and spreading from the cortex into the nucleus. However, the loss of potassium and increase in sodium concentration occurred at early stages in both the cortex and nucleus cells, possibly because these cells are interconnected by gap junctions. There is a local alteration in elemental content prior to morphologically demonstrable cataract formation.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Quantitative microlocalization of diffusible ions in normal and galactose cataractous rat lens by secondary ion mass spectrometry. 382 Feb 81

Lens retrodots are round, oblong, or oval features in the perinuclear zone of the adult lens after the fifth decade of life and associated with cataract. Retrodots were found in 47 out of 121 eyes with cataract (39%) in the present series. They show birefringence in vivo and in vitro, and chemical studies suggest that they contain calcium oxalate. It is proposed that ascorbic acid, which is abundant in the normal human lens, is the most likely source for this oxalate. Ascorbic acid is thought to have a protective role against oxidative stress in the lens and other parts of the eye, and its level is known to be reduced in senile cataract. The presence of the retrodots may identify lenses which have been exposed to oxidative stress and are less capable of resisting oxidative damage.
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PMID:Perinuclear lens retrodots: a role for ascorbate in cataractogenesis. 382 68

Meticulous studies of the pathophysiology of postoperative eyes are mandatory to find the means of reducing the risks of intraocular surgery. Various methods of examination developed for this purpose are described and their clinical significance discussed. The corneal endothelium shows no proliferative capacity even after injury and great care must be taken to protect this vulnerable cell layer. Drugs may be toxic to the corneal endothelium and their use during surgery must be exercised with caution. The intraocular irrigating solutions must contain calcium and have an appropriate salt composition. Pupillary constriction that occurs during extracapsular cataract extraction is due mainly to prostaglandins synthesized as a result of surgical trauma; this can be prevented by the preoperative use of topical indomethacin. Breakdown of the blood-aqueous barrier after intraocular surgery may also be due to a similar mechanism, and preoperative topical non-steroidal anti-inflammatory agents (indomethacin, flurbiprofen and diclofenac) can prevent this phenomenon, as studied by fluorophotometry. Topical indomethacin also prevents cystoid macular oedema after cataract surgery. Based on the biochemical findings on inflammation after tissue injury, a protocol for the preoperative and postoperative use of corticosteroid and non-steroidal anti-inflammatory agents is proposed for anterior segment surgery.
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PMID:Pathophysiology and pharmacology of intraocular surgery. 390 61


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