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At least 1,639 records · Page 91Linked to original sources
PubMed2004

Production of 5alpha-reduced neurosteroids is developmentally regulated and shapes GABA(A) miniature IPSCs in lamina II of the spinal cord.

In lamina II of the spinal dorsal horn, synaptic inhibition mediated by ionotropic GABA(A) and glycine receptors contributes to the integration of peripheral nociceptive messages. Whole-cell patch-clamp recordings were performed from lamina II neurons in spinal cord slices to study the properties of miniature IPSCs (mIPSCs) mediated by activation of GABA(A) and glycine receptors in immature (<30 d) and adult rats. Blockade of neurosteroidogenesis by 1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinoline carboxamide (PK11195), an inhibitor of the peripheral benzodiazepine receptor (PBR), or finasteride, which blocks 5alpha-reductase, accelerated the decay kinetics of GABA(A) receptor-mediated mIPSCs in immature, but not in adult animals. Glycine receptor-mediated mIPSCs remained unaffected under these conditions. These results suggest the presence of a tonic production of 5alpha-reduced neurosteroids in young rats that confers slow decay kinetics to GABA(A) mIPSCs. At all of the ages, selective stimulation of PBR by diazepam in the presence of flumazenil prolonged GABA(A) mIPSCs in a PK11195- and finasteride-sensitive manner. This condition also increased the proportion of mixed GABA(A)/glycine mIPSCs in the immature animals and led to the reappearance of mixed GABA(A)/glycine mIPSCs in the adult. Our results might point to an original mechanism by which the strength of synaptic inhibition can be adjusted locally in the CNS during development and under physiological and/or pathological conditions by controlling the synthesis of endogenous 5alpha-reduced neurosteroids.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed2006

Transposition of a fungal miniature inverted-repeat transposable element through the action of a Tc1-like transposase.

The mimp1 element previously identified in the ascomycete fungus Fusarium oxysporum has hallmarks of miniature inverted-repeat transposable elements (MITEs): short size, terminal inverted repeats (TIRs), structural homogeneity, and a stable secondary structure. Since mimp1 has no coding capacity, its mobilization requires a transposase-encoding element. On the basis of the similarity of TIRs and target-site preference with the autonomous Tc1-like element impala, together with a correlated distribution of both elements among the Fusarium genus, we investigated the ability of mimp1 to jump upon expression of the impala transposase provided in trans. Under these conditions, we present evidence that mimp1 transposes by a cut-and-paste mechanism into TA dinucleotides, which are duplicated upon insertion. Our results also show that mimp1 reinserts very frequently in genic regions for at least one-third of the cases. We also show that the mimp1/impala double-component system is fully functional in the heterologous species F. graminearum, allowing the development of a highly efficient tool for gene tagging in filamentous fungi.

Base Sequence↗
PubMed1981

[A comparative study on the prevalence of pleural thickness related with asbestos exposures. A comparison between urban and rural districts using miniature X-ray films (author's transl)].

Using miniature films for mass tuberculosis examination of inhabitants, a comparison was made of the prevalence of pleural thickening between urban and rural districts in Japan. The classification of pleural thickening mostly followed the criteria of Askergren and Szamosi. Age adjusted prevalences for male adults were 2.7% (Ys city) and 5.3% (Yk city) in urban districts, and 0.7% (Hokuriku district) in rural districts. In addition to the survey of these inhabitants, workers of a ship building factory in the urban district were examined. Age adjusted prevalence in this case was 7.3%. On the other hand, the prevalence for female adults were 0.2% (Ys city) and 0.4% (Yk city) in the urban districts, and 0.09% in the rural districts. The prevalence of pleural thickening showed a sharp increase after 60 years of age in male adults but not in female adults. It was confirmed that pleural calcification was a better diagnostic feature for distinguishing the difference of prevalence by areas.

Adult↗
PubMed1988

Solvent constituents in paint, glue and thinner for plastic miniature hobby.

Solvent-containing products (8 paint, 29 glue and 4 thinner preparations) for plastic miniature hobby were analyzed for solvent constituents by capillary gas-chromatography. Acetone and methyl isobutyl ketone were two most extensively used solvents both in terms of frequency and concentration. Other popular solvents included ethyl alcohol and two esters of ethyl acetate and butyl acetate. In contrast, aromatics, chlorinated hydrocarbons and ethylene glycol derivatives were seldomly detected. The present findings were discussed in comparison with the observation on the materials abused for sniffing in the past, as well as constituents in the products for industrial application.

Adhesives↗
PubMed2005

An outbreak of besnoitiosis in miniature donkeys.

Fourteen miniature donkeys (Equus asinus) in a mid-Michigan herd of 38 animals presented with clinical signs of besnoitiosis, including the presence of typical tissue cysts in the ocular sclera, the buccal and nasal mucosa, together with characteristic dermatitis in specific areas of the body. The common histopathological change seen was the presence of many 100-200-microm diameter, thick walled, typical Besnoitia sp. tissue cysts together with a chronic cellular response associated with degenerating cysts. Microscopy of isolated scleral cysts and skin biopsies showed the presence of protozoal organisms consistent in morphology with that of Besnoitia bennetti bradyzoites. Molecular analysis of these parasites indicates that they differ from previously described coccidia, including Besnoitia sp., from rabbits and opossums. Isolated cases of infection with this agent have been reported infrequently in equids; however, this is the first report of an outbreak in a herd of donkeys in the United States.

Animals↗
PubMed1979

Plasma oxytocin and steroid concentrations during late pregnancy, parturition and lactation in the miniature pig.

Plasma oxytocin concentrations were measured during late pregnancy, parturition and lactation in the miniature pig. Measurements were made of plasma oestradiol, oestrone and progesterone to determine whether there was any relationship between the concentrations of oxytocin and these steroids in the circulation. Plasma oxytocin concentrations were low or undetectable in late pregnancy. Rises of up to 68.8 mum./ml were seen at the time of delivery of the foetuses and at the expulsion of the placenta. The only steroid that seemed to relat to oxytocin release was progesterone. Oxytocin release was consistently seen when progesterone concentrations had fallen to below 10 ng/ml but no increase in concentration was observed while oestrone and oestradiol increased to their maximum concentrations of 3.86--11.6 and 0.43--0.70 ng/ml respectively. During lactation, when both oestrogen and progesterone concentrations were low, suckling caused the levels of oxytocin to increase to 7.4 muu./ml. These increases were greater during the first 2 weeks of lactation than later.

Animals↗
PubMed1981

Intranuclear inclusions in the bone marrow cells of miniature pigs.

Intranuclear inclusions were found in bone marrow cells of miniature pigs, whose ultrastructure and nature were examined by electron microscope and by cytochemical techniques. The inclusions were found predominantly in the granulocyte series and in a megakaryocyte and plasma cell. The inclusions consisted of closely packed, wavy filaments, 20-40 in number. They varied in size from 0.5-1.0 mum in length and 0.2-0.5 mum in width. The largest inclusion extended across the entire length of the nucleus. Occasionally, an inclusion extending toward the nuclear pore was observed. the intranuclear inclusions showed a tendency to appear frequently in immature granulocytes. The experiment on enzyme digestion for the epoxy sections showed that the inclusions were insoluble in RNase, DNase, pepsin, trypsin and protease solutions. These results seem to suggest that the intranuclear inclusions of blood cells differ from filamentous inclusions which have been noted previously in some neurons.

Animals↗
PubMedDate not supplied

Congenital myasthenia gravis in Smooth-Haired Miniature Dachshund dogs.

Three 8-week-old Miniature Smooth Haired Dachshund littermates were diagnosed with myasthenia gravis based on clinical signs, results of electrophysiological testing, and response to the short-acting anticholinesterase drug, edrophonium chloride. Congenital myasthenia gravis was confirmed by the demonstration of decreased acetylcholine-receptor density in external intercostal muscle in the absence of demonstrable serum antiacetylcholine receptor antibody or antibodies complexed to acetylcholine receptors in muscle biopsy samples. Unlike most previously reported cases of congenital myasthenia gravis that are relentlessly progressive, clinical signs resolved spontaneously by 6 months of age.

Aging↗
PubMed1980

The healing of gingival wounds in miniature swine.

Standard wounds of simple incision and partial excision of the dentogingival junction were made in miniature swine. The healing from the 1st to the 14th day were described clinically and histologically, and the standardization of the wounds permitted quantitative and statistical analysis. In wounds that are closely adapted to the tooth, the epithelium of the new dentogingival junction contributes primarily to early wound strength recovery. This functional achievement probably would not occur with thick clots or hematomas, or with any displacement of the gingiva away from the tooth.

Animals↗
PubMed2003

A miniaturized fluorescence detector with a windowless flow cell using a light-emitting diode.

A miniaturized fluorescence detector using a high-brightness light-emitting diode as an excitation source was constructed and evaluated. A windowless flow cell based on a commercial four-port cross fitting was designed to reduce the stray-light level and to eliminate the optical alignment. The observed detection limit for fluorescein was 26 nM in the continuous-flow mode. The error in the reproducibility of the responses was evaluated by the FIA method, and was found to be within 2% RSD.

Journal Article↗
PubMed2006

Micro-miniature autonomous optical sensor array for monitoring ions and metabolites 1: design, fabrication, and data analysis.

A micro-miniature array of sensing capsules for optical monitoring of pH, potassium and glucose is described. Optode technology translates the respective ionic levels into variable colors of ionophore/dye/polymeric liquid micro-beads stuffed into individual capsules. Glucose is monitored indirectly, by coupling through glucose oxidase (GOX) immobilized in cellulose acetate phthalate (CAP) based microscopic beads that are stuffed into another microcapsule together with pH sensitive optical microscopic beads. The electrolyte and glucose sensing capsules are embedded in a transparent cellulose acetate bar 300-500 microm wide and 2-2.5 mm long called the sliver sensor that includes also a white capsule made of micro-beads without dye for optical reference. By adding further capsules custom combinations of analytes can be monitored in biomedical and non-biological contexts. In this work, as an example, design, fabrication and testing of a sliver sensor that could be developed for in vivo use are described.

Biosensing Techniques↗
PubMed2006

Miniature liquid flow sensor and feedback control of electroosmotic and pneumatic flows for a micro gas analysis system.

Accurate liquid flow control is important in most chemical analyses. In this work, the measurement of liquid flow in microliters per minute was performed, and feedback control of the flow rate was examined. The flow sensor was arranged on a channel made in a polydimethylsiloxane (PDMS) block. The center of the channel was cooled by a miniature Peltier device, and the change in temperature balance along the channel formed by the flow was measured by two temperature sensors. Using this flow sensor, feedback flow control was examined with two pumping methods. One was the electroosmotic flow method, made by applying a high voltage (HV) between the reagent and waste reservoirs; the other was the piezo valve method, in which a micro-valve-seat was fabricated in a PDMS cavity with a silicone diaphragm. The latter was adopted for a micro gas analysis system (microGAS) for measuring atmospheric H2S and SO2. The obtained baselines were stable, and better limits of detection were obtained.

Air Pollutants↗
PubMed1983

Anti-botulismic effect of toosendanin and its facilitatory action on miniature end-plate potentials.

The time for blocking neuromuscular transmission by botulinum toxin is lengthened in phrenic nerve-diaphragm preparation of rats sacrificed at various times after subcutaneous injection of toosendanin (7 mg/kg). This effect of toosendanin manifests itself 15 min after injection and lasts for 3 days. During this period the frequency of miniature end-plate potentials is increased.

Action Potentials↗
PubMed1989

Effects of cesium ions on the frequency of miniature end-plate potentials at the frog neuromuscular junction.

The effects of Cs ions on the frequency of miniature end-plate potentials (MEPPs) were investigated at the frog neuromuscular junction. The frequency of MEPPs increased gradually with time, after a delay, when part of the NaCl in normal Ringer's solution was replaced isotonically with CsCl. The delay was greatly prolonged and the rate of increase in MEPP frequency slowed when a low concentration--between 6 and 40 mM--of CsCl was applied. As the external concentration of CaCl2 (0.4-6.3 mM) was increased, the delay was prolonged and the rate of increase became slower. The effect of Mg ions was qualitatively the same as that of Ca ions. In the case of reapplication, Cs ions produced a prompt increase in MEPP frequency and the rate was much faster than before. When the solution contained no added Ca and 1 mM EGTA, no appreciable change in MEPP frequency was observed when CsCl was applied. It is suggested that the first step in the gradual increase in MEPP frequency is the slow entry of Cs ions into the nerve terminal, following which transmitter release is mainly induced by the influx of external Ca ions.

Action Potentials↗
PubMed1979

Genetic selection for diabetogenic traits in Yucatan miniature swine.

Yucatan miniature pigs have been selectively bred for reduced and increased glucose clearance during an intravenous glucose tolerance test. Pigs with low glucose clearance rates (low K) have been selected through the F-5 generation. They have a significantly reduced rate of glucose clearance and a blunted peripheral IRI increase in response to the challenge. Through the F-5 generation, heritability of glucose tolerance is estimated at 0.26. Sporadic fasting blood glucoses in excess of 100 mg/dl are seen in later generations of this group. High glucose clearance pigs (high K) have been selected through the F-4 generation. They have significantly increased rates of glucose clearance and a greater increase in peripheral IRI than the low K animals. The estimated heritability for high K through the F-4 generation is 0.31. No evidence of fasting hypo- or hyperglycemia has been seen in the high K animals.

Animals↗
PubMedDate not supplied

Control of insulin-dependent diabetes with portable miniaturized infusion systems.

A method of insulin therapy that appears to achieve better control of diabetes than present conventional methods is the use of insulin infusion devices--either glucose-controlled feedback (closed-loop) systems or the preprogrammed (open-loop) infusion pump. In view of the problems with implantable glucose sensors, we have worked to develop a miniaturized, programmable infusion system. Its use in insulin-dependent diabetic patients to provide either intravenous doses or a continuous subcutaneous insulin infusion resulted in significant reductions in blood glucose levels, glycemic excursions and 24-h glucose excretion.

Blood Glucose↗