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11.
Summary Growth and biomass protein formation by filamentous fungi grown on pretreated tropical woods of Mesta (Hibiscus cannabinus Linn.) and Subabul [Leucaena leucocephala (Lam.) de Witt] as well as their isolated hemicellulose and cellulose fractions have been studied. Penicillium janthinellum and Penicillium funiculosum produced a biomass having 20 to 30% crude protein when grown on either hemicellulose, while growth on pretreated (autoclaved in 1% NaOH) wood or isolated cellulose fractions was comparatively poor and crude protein content only 5 to 8% in the biomass.NCL Communication no.3550  相似文献   
12.
Rabbit articular chondrocytes in suspension culture synthesize Type II collagen [3alpha1(II)] in the absence of extracellular Ca2+ and Type I collagen [2alpha1(I) - alpha2] in the complete medium. As a result of pre-treatment in monolayer culture with calcitonin or parathyroid hormone in the complete medium, an influx of Ca2+ into the cells occurs. These cells produce mainly Type I collagen when transferred to suspension cultures in the medium devoid of CaCl2. If added directly to the suspension culture medium containing no CaCl2, calcitonin stimulates an active efflux of Ca2+ from the cells into the medium and leads the cells to synthesize Type I collagen. Under similar conditions, parathyroid hormone does not change the collagen-phenotype.  相似文献   
13.
Acute mitochondrial insult has been suggested as a primary reason for the clinical, histopathological and biochemical abnormalities seen in Reye's syndrome. However, the etiology of mitochondrial dysfunction has not been identified. Polyamines have been known to alter the mitochondrial structure and function. Influenza infection may cause an increase in ornithine decarboxylase activity and thereby channel ornithine for polyamine biosynthesis, leading to mitochondrial dysfunction in Reye's syndrome. To test this hypothesis, the hepatic concentrations of polyamines, polyamine-metabolizing enzymes and urea cycle enzyme activities in Reye's syndrome patients were determined and compared with patients who died from illnesses other than Reye's syndrome. The hepatic concentration of putrescine, spermidine and spermine were increased in Reye's syndrome patients. The activity of ornithine decarboxylase was elevated but, due to the small number of samples, these values did not reach statistical significance. Ornithine carbamoyltransferase activity was decreased in the liver of Reye's syndrome patients. Our results suggest that increased synthesis of polyamines from ornithine may initiate mitochondrial injury in Reye's syndrome.  相似文献   
14.
The modulatory role of endogenous cellular glycosphingolipids in bradykinin-stimulated myo-inositol 1,4,5-trisphosphate (InsP3) formation by MDCK cells was evaluated utilizing the glucosylceramide synthase inhibitor, threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP). Bradykinin-stimulated InsP3 formation in intact cells and in isolated plasma membranes was significantly enhanced when cells were first depleted of their glucosphingolipids. The effect of glucosphingolipid depletion on phospholipase C activity was dependent on the duration of exposure to the inhibitor and the cellular level of glucosylceramide. Inclusion of glucosylceramide in the culture medium prevented the stimulatory effect of PDMP on InsP3 formation. It is concluded that membrane glucosphingolipids may regulate phospholipase C activity.  相似文献   
15.
Phosphomonoesterase and diesterase that cleave phosphatidylinositol-4-phosphate (diphosphoinositide, DPI) and phosphatidylinositol-4,5-bisphosphate (triphosphoinositide, TPI) were detected in three subfractions of purified rat brain myelin, and some properties of the enzymes were studied. Monoesterase activity was stimulated by KCl, maximally at a concentration of 25 mM, and inhibited at KCl concentrations above 50 mM. Addition of boiled pH 5 supernatant of rat brain homogenate doubled the enzymic activity; EDTA was inhibitory. The specific activities were nearly equal in the low density, medium density, and heavy density myelin fractions but about 30% lower than in whole brain homogenate. The monophosphatase could be solubilized by extraction with 0.2% Triton X-100. The phosphodiesterase activity was inhibited by EDTA and EGTA and not stimulated by KCl or pH 5 supernatant. Specific activities were nearly equal in whole brain and myelin but were by about 60 percent elevated in the heavy density over the low density myelin fraction. These results show that the hydrolases operative in the fast turnover of the inositide phosphate groups are distributed over the entire myelin structure.  相似文献   
16.
Abstract: At intervals ranging from 1 to 10 min after injection of 32Pi into rat brain, myelin was prepared and separated into three subfractions: heavy, medium, and light. The radioactivity of total phospholipids and polyphospho-inositides (PPI) was then determined. There was rapid incorporation of 32Pi into PPI, which contained 50–70% of the radioactivity among total brain lipids and more than 70% among myelin lipids. The myelin fraction had incorporated 32Pi into total recovered PPI in the order of medium > heavy > light fraction: however, the order of relative specific radioactivities was heavy > light > medium. Labeling of the PPI precursors, phosphatidic acid (PA) and phos-phatidylinositol (PI), was considerably lower in the purified myelin than in total brain. The di- (DPI) and triphosphoinositides (TPI) in heavy myelin exchanged 32Pi at rates 2 to 3 times faster than those in medium and light myelin. DPI of all subfractions of myelin exchanged much faster than TPI. The results show that the most active phosphate turnover of myelin PPI occurs in the heavy myelin fraction (probably largely consisting of myelin appurtenant regions). However, medium and light myelin (most probably representing the closely packed layers of myelin sheaths) also showed rapid turnover of PPI.  相似文献   
17.
Abstract: Age-dependent changes in the oxidative metabolism in nonsynaptic and synaptic mitochondria from brains of 3, 12, and 24-month-old rats were investigated. When pyruvate and malate were used in conjunction as substrates, a significant reduction in State 3 respiration was observed in both mitochondrial populations from 12-and 24-month-old rats compared with 3-month-old animals. A similar age-dependent reduction in the oxidation of [1-11C]pyruvate was also observed in nonsynaptic and synaptic mitochondria from senescent rats. Pyruvate dehydrogenase complex activity (both active and total) was, however, not decreased in the two mitochondrial populations from brains of 3, 12, and 24-month-old rats. When DL-3-hydroxybutyrate plus malate were used as substrates, a decrease in State 3 respiration was observed only in synaptic mitochondria from 24-month-old rats compared with 3- month-old animals. Similarly, an age-dependent reduction in the oxidation of 3-hydroxy[3-11C]butyrate was also observed only in synaptic mitochondria from 12-and 24-month-old rats. However, a significant reduction in the activities of ketone body-metabolizing enzymes, namely, 3-hydroxybutyrate dehydrogenase, 3-ketoacid CoA transferase, and acetoacetyl-CoA thiolase was observed in both mitochondrlal populations from 12- and 24-month-old rats compared with 3 month-old animals. These findings show that specific alterations in oxidative metabolism occur in nonsynaptic and synaptic mitochondria from aging rats. The data also suggest that in addition to alterations in enzyme activities, permeability of anions (e.g. pyruvate) across the inner mitochondrial membrane may be altered in nonsynaptic and synaptic mitochondria from senescent animals.  相似文献   
18.
19.
Objective: The objective of this study was to fabricate a successful implant for temporomandibular joint (TMJ) disorder patients who could not be treated through conventional surgeries.

Methods: A custom-made implant was fabricated using rapid prototyping (RP) for the TMJ surgery. The stability of the metallic implant was validated using a finite element analysis.

Results: The results of finite elements were stable and the design of the TMJ implant was suitable as per the patient's need. The customised implant was made using a fused deposition modelling method of RP and a vertical machining centre. The implant has provided normal jaw function for over 2 years since surgery.

Conclusions: The approach utilised will be helpful in providing successful treatment to the deformed mandible and the mandible joints. This method allows to customise and to accurately fabricatie the implant. Advantages of this approach are that the physical model of the implant was tested for stability before the implantation, the surgeon can plan and rehearse the surgery in advance, it is a less invasive and less time-consuming surgical procedure.  相似文献   
20.
Neurochemical Research - Parkinson’s disease (PD) is a slow progressive, second most common neurodegenerative disease characterized by the loss of dopaminergic neurons from the nigrostriatal...  相似文献   
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