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PubMed2002

[Experimental study on effects of self-made miniature axial flow blood pump as left ventricle assistance for postischemic heart].

OBJECTIVE: To evaluate the effects of self-made miniature axial flow blood pump as left ventricle assistance for postischemic heart. METHODS: Sixteen adult healthy sheep were divided into two groups of 8 sheep. After acute left heart failure was induced by selective ligation of the left anterior descending branch of coronary artery for 1.5 hours and ligation of the left circumflex branch for half an hour, one hour of reperfusion with assistance by self-made blood pump was offered in experimental group and no mechanical assistance was given to the control group. The sheep were killed after the experiment and their hearts were taken to be observed. During the experiment, the changes in hemodynamic and hemologic indices were compared between the two groups to assess the effects of left heart assistance on hemodynamics and blood by self-made blood pump. RESULTS: After 1 hour of assistance by self-made blood pump, experimental group, in comparison with the control group, showed a significant (P < 0.05) increase in total cardial output (3.11 +/- 0.3 vs 2.37 +/- 0.3 L/min), mean aortic pressure (73 +/- 5.4 vs 66 +/- 3.1 mm Hg), and left ventricular Dp/Dt(max) (1 415 +/- 2 549 vs 986 +/- 8 mm Hg/sec); and a significant decrease in left ventricular end diastolic pressure (11.8 +/- 2.1 vs 13.5 +/- 1.4 mm Hg) and left atrial pressure (14.1 +/- 1.6 vs 16.0 +/- 1.6 mm Hg) (all P < 0.05). There was no significant difference in plasma free hemoglobin (12.4 +/- 3.1 vs 13.8 +/- 4.7 mg/dl) and fibrinogen (0.32 +/- 0.12 vs 0.42 +/- 0.12 g/dl) between these two groups. CONCLUSION: 1, Animal model for acute left heart failure can be achieved by selective ligation of coronary arteries and satisfactorily used in left ventricular assist device assessment. 2. Self-made blood pump can be used in assistance for failure heart without serious event.

Animals↗
PubMed1975

In vitro cultivation and identification of aortic endothelium from miniature pig.

Pieces of miniature pig aorta were explanted endothelial face down directly on the bottom of Petri dishes. On removal of the aorta fragments after 2-4 days of incubation single cells or small groups of viable endothelium were found attached. The cells developed into a permanent line (at present over 18 passages) and were identified as pure endothelial cells both by light- and electron microscopic examination.

Animals↗
PubMed1975

[Teratogenic action of ethyl-nitrosourea in Göttingen miniature pigs (author's transl)].

By i.p. application of 70 or 100 mg/kg ethyl-nitrosourea, resp., to gravide Göttingen miniature pigs on days 14 or 16, resp., of gestation massive malformations of the skeletal system were produced. The experiments demonstrated the teratogenic effect of ethylnitrosourea on non-rodents, ascertained the period of determination of the skeletal system in pigs, confirmed the concentration effect in teratogenesis as well as the ineffectiveness of biological barriers with adequately high dosages.

Abnormalities, Drug-Induced↗
PubMed2002

[Preventive therapy in middle-aged and elderly persons selected from the population-based screening by mass miniature radiography--methodological aspect and adverse reactions].

The notification rate of tuberculosis in Japan was 31.0 per 100,000 in 2000. The rate was especially high among the elderly population, reaching 85.5 per 100,000 among those over 65 years of age. We conducted a study of preventive therapy in middle-aged and elderly persons selected from the population-based screening by the mass miniature radiography. The eligible criteria were 50-79 years of age, fibrous lesion which were compatible with healed tuberculosis and showed no change for at least one year, no previous treatment for tuberculosis, normal liver function tests, and no serious disease at the time of study. The eligible criteria for liver function tests in this study was less than 50 IU/L of AST and ALT value, and less than 1.5 mg/dl of T-bil level. A total of 13,219 people underwent TB screening in 4 cities in 1997 and 2 cities in 1998. Among them, 440 persons fulfilled the above criteria based on the screening records and chest X-ray films. The municipal offices sent letters to 418 people, except 22 whose addresses were unknown, to obtain permission to use their addresses and results of screening in our study. Permission was obtained from 137 persons and we sent them invitation letters for cost-free physical checkup service. Ninety-five persons visited us, and we offered them physical checkup and explained about our study. After obtaining the informed consent, we performed chest X-ray and sputum examination for 3 consecutive days. Finally 29 people were enrolled in the study. They were divided into 4 groups by sex and age, and were randomly assigned to one of two treatment groups. One group took 300 mg of INH per day for 6 months and the other group was only followed up by chest X-ray. Fourteen out of 29 persons began to take INH and received monthly liver function test. All the subjects were scheduled to follow by medical checkup every 6 months for 5 years. The proportion of taking INH tablets was estimated to range from 94% to 100%, based on the calendar for record of taking medication and the number of remaining tablets each month. Six (42.9%) of 14 persons reported adverse reactions. Two of 6 persons complained some of diarrhea, vomiting and gastrointestinal disturbance within 2 weeks, and discontinued taking INH, although none of them showed abnormal liver function tests. Two of 6 persons who reported some kinds of symptoms and 2 of 8 persons who did not complain of any symptoms showed abnormal liver function tests. The abnormal liver function tests had developed from 2 months after the beginning of INH taking in most of the persons and the abnormality improved after the completion of 6-month treatment. We have followed them for a maximum duration of 2.5 years, and 3 cases dropped out from the study. These defaulted cases had completed 6 months of INH. One person (69 y.o. male) was diagnosed as active TB by his chest X-ray film at the 6th month medical checkup, although it was not confirmed bacteriologically. One person (62 y.o. female) had the mastectomy for breast cancer 7 months before the entry to this study and relapsed at the 8th month after the entry. One person (73 y.o. female) was diagnosed as lung cancer at the medical checkup on 2.5 years. Besides them, 4 persons were suspected of worsening the abnormal shadows on chest X-ray films; one was from the INH group and three were from the follow-up group. However none of them was diagnosed clinically and bacteriologically as active tuberculosis.

Aged↗
PubMed1976

High-performance colorimeter with an electronic bubble gate for use in miniaturized continuous-flow analyzers.

We describe a high-performance colorimeter with an electronic bubble gate for use with miniaturized continuous-flow analyzers. The colorimeter has a flow-through cuvette with optically flat quartz windows that allows a bubbled stream to pass freely without any breakup or retention of bubbles. The fluid volume in the light path is only 1.8 mul. The electronic bubble gate selectively removes that portion of the photodector signal produced by the air bubbles passing through the flow cell and allows that portion of the signal attributable to the fluid segment to pass to the recorder. The colorimeter is easy to use, rugged, inexpensive, and requires minimal adjustments.

Autoanalysis↗
PubMedDate not supplied

[A portable miniature IMD-01 X-ray dosimeter for monitoring the dose power in radiodiagnosis].

The paper presents a portable miniature [symbol: see text]-01 X-ray dosimeter designed by the Research Institute of Introscopy, Spektr Moscow Research-and-Production Association, for monitoring the power of a dose during X-ray diagnosis. The device ensures the monitoring of the power of a dose at the input of X-ray detectors of diagnostic apparatuses and, with the use of special methods, makes it possible to control the state of the protection devices of X-ray diagnostic apparatuses. An ionization chamber is used as a detector of X-ray radiation. The technical data of the dosimeter are given.

Equipment Design↗
PubMed1976

Serum protein concentrations and enzyme activities, as functions of age and sex, in Sinclair (S-1) miniature swine.

Venous blood samples were collected monthly from 60 male and 60 female Sinclair (S-1) miniature swine from 1 through 36 months of age. Serum total protein concentration increased linearly from 1 through 10 months of age and remained stable thereafter with no sex related difference. Serum albumin concentration decreased from 1 through 3 months, increased from 3 through 8 months and decreased from 14 through 36 months. From 2 through 36 months, serum alpha-globulin concentration decreased; whereas, serum beta-globulin concentration increased. Serum gamma-globulin concentration increased markedly from 1 through 3 months and continued to increase through 36 months of age. From 10 through 36 months, males had a greater mean serum gamma-globulin concentration than did females. Serum total globulin concentration increased most rapidly from 1 through 3 months, less rapidly from 3 through 18 months and remained stable thereafter. Serum albumin/globulin ratio decreased sharply from 1 through 3 months and continued to decrease from 6 through 36 months with females having a greater mean concentration than males. Serum glutamic-oxaloacetic transaminase activity decreased from 1 through 30 months with males having a greater mean activity than females from 7 through 36 months of age. Serum alkaline phosphatase activity decreased from 1 through 36 months of age with no sex related difference. Serum lactic dehydrogenase activity decreased from 1 through 30 months with females having a greater mean activity than males from 24 through 36 months of age.

Age Factors↗
PubMed1976

Automated enzymic determination of ethanol in blood, serum, and urine with a miniature centrifugal analyzer.

We describe an automated spectrophotometric reaction-rate method for determination of ethanol in serum and urine with a miniature centrifugal analyzer. The theanol is selectively oxidized in the presence of alcochol dehydrogenase and NAD+ to form NADH, which is measured by the rate of change of its absorbance. Reaction rates are determined automatically, and unknown concentrations are calculated from a computer-generated working curve based on aqueous ethanol standards. Blood, serum, or urine specimens need not be deproteinized. The method permits duplicate analysis of at least 30 samples per hour. Coefficients of variation and relative errors are about 2-3% for ethanol concentrations of 0.3-3.0 mug per 2 mul of sample. Analytical recovery of ethanol added to serum is 92-103% (average, 98.5%). Comparisons with distillation-oxidation, gas-chromatographic, and conventional enzymic procedures give satisfactory agreement.

Alcohol Oxidoreductases↗
PubMed1976

Adaptation of "EMIT" technique for serum phenobarbital and diphenylhydantoin assays to the miniature centrifugal analyzer.

We used a miniature centrifugal analyzer in a spectrophotometric rate-measurement mode to determine the anticonvulsant drugs phenobarbital and diphenylhydantoin in serum, by use of a modified enzyme immunoassay ("EMIT", Syva Corp.) We decreased reagent cost per determination by at least sixfold by means of microscale techniques. Also, the analysis rate is increased by measuring multiple samples simultaneously. Our method requires only 3 mul of serum for duplicate determinations. Replicate analyses of sera containing phenobarbital and diphenylhydantoin gave reaction rates with a CV of 1.5%. Run-to-run CV was 15%. Analytical recovery for drug-supplemented serum samples was 98%, and results for a series of samples compared well with results obtained by gas chromatography (for phenobarbital, r = 0.95; for diphenylhydantoin, r = 0.91).

Centrifugation↗
PubMed1992

[Atypical endplate miniature potentials in the frog neuromuscular junction after modification of the intercellular matrix and osmotic exposures].

In frog cutaneous-pectoris muscles the frequency of slowly rising atypical miniature endplate potentials (MEPPs) was significantly enhanced after collagenase (0.1%) treatment. Treatment with trypsin, hyaluronidase, hyper- and hypoosmotic solutions caused no changes in slowly rising MEPP (frequency in muscle fibers with intact acetylcholinesterase (AChE). Inhibition of AChE caused appearance of giant MEPPs. Acceleration of acetylcholine diffusion from synaptic cleft after treatment with hyaluronidase decreased giant MEPP frequency demonstrating their dependence upon nonhydrolyzed acetylcholine in synaptic cleft. The relation between slowly rising MEPPs and activity of synaptic Schwann cells in discussed.

Acetylcholine↗
PubMed1992

Obstructive enterolith in an 11-month-old miniature horse.

An obstructive enterolith was diagnosed in an 11-month-old 68-kg miniature horse with a 24-hour history of mild, intermittent colic. Abdominal radiography revealed gas distention of the cecum and the right and left ascending colon, and a radiodense elliptical structure in the area of the left kidney. During exploratory laparotomy, the right dorsal colon was noticed to contain ecchymotic hemorrhage and generalized discoloration in the portion proximal to the location of the enterolith. While exteriorizing the ascending colon, it ruptured caudal to the diaphragmatic flexure in the right dorsal colon. Radiography of the enterolith did not reveal a metallic center, but division of the stone allowed identification of a canvas cloth, and chemical analysis determined the stone's composition to be ammonium magnesium phosphate. Although equine enteroliths were reported over 100 years ago and the factors involved in their formation were investigated, the reasons for their development have yet to be determined. The mean reported age of horses requiring abdominal surgery because of an obstructive enterolith is 10 years, with the youngest being 4 years. The time required for an enterolith to enlarge is unknown, although a true enterolith has not been reported in horses younger than 4 years of age.

Animals↗
PubMed1992

[Effects of ouabain on 201Tl and 99mTc MIBI kinetics in rat myocardium--in vivo study using miniature CsI detector].

The aim of this study is to investigate the effect of ouabain (inhibitor of Na-K ATPase) in the myocardial uptake and clearance of 201Tl and 99mTc MIBI using rats. Time activity curves of three groups were measured by CsI miniature detector for 15 min after the administration of each radiopharmaceutical. Groups were divided as follows; 1) control group (CON group), 2) early phase as 15 min after the administration of ouabain (OU15 group), and 3) late phase as 120 min after the administration of ouabain (OU120 group). Main organs of rats including myocardium were resected at 1 min and 15 min after the administration of 201Tl or 99mTc MIBI under the anesthesia of pento-barbital sodium. The uptake (%ID/g) of 201Tl or 99mTc MIBI was measured by well type scintillation counter. The uptake of 201Tl of OU15 group was significantly higher than CON group (OU15: 10.81 +/- 1.90, CON: 1.86 +/- 0.42) and cleared more rapidly. On the contrary, OU120 group showed lower uptake (1.70 +/- 0.21) and slower clearance than OU15 group. Time activity curve of OU15 group indicated the accelerated washout compared with CON group. However, OU120 group showed significantly the reduced washout (CON group: 19%, OU15 group: 22%, OU120 group: 9%). On the other hand, the uptake and time activity curves of 99mTc MIBI were not influenced by ouabain administration. In conclusion, myocardial uptake and clearance of 99mTc MIBI were not related to Na-K ATPase activity, while those of 201Tl were markedly influenced by Na-K ATPase.

Animals↗
PubMed1977

[Resting membrane potentials and miniature postsynaptic potentials of frog intrafusal muscle fibers].

Electrophysiological charact eristics of frog intrafusal muscle fibers were studied by means of the intracellular potential recording. Analysis of distribution of the amplitude of miniature postsynaptic potentials suggests the nonuniformity of the intrafusal muscle fibers. A conclusion was drawn on the presence of three types of intrafasal muscle fibers in frog muscle spindle: single-innervated, multiple innervated, and fibers with both types of innervation.

Animals↗
PubMed1977

Transplantation in miniature swine. II. In vitro parameters of histocompatibility in MSLA homozygous minipigs.

A selective breeding program based on serological techniques was used to establish three herds of miniature swine, each homozygous for a different allele at the major histocompatibility complex, termed MSLA. By selective immunization of these swine, high-titered antisera detecting the products of individual MSLA alleles were raised and used to confirm the genotype of offspring in these herds. Techniques for performing one-way mixed leukocyte cultures in these pigs were developed and demonstrated the presence of a strong mixed leukocyte culture locus (or loci) closely linked to the serologically defined MSLA locus. Cell-mediated cytotoxicity assays based on 51Cr release were developed to monitor the course of cellular immunity following allotransplantation and exhibited specificity identical to that predicted by the serological typing.

Animals↗
PubMed2003

[Modulation of extracellular calcium on miniature inhibitory postsynaptic currents of Xenopus' optic tectal neurons].

Experiments were performed to study the relationship between presynaptic calcium and miniature inhibitory postsynaptic currents (mIPSCs) using voltage-clamp technique with whole cell mode in Xenopus optic tectal slices. The results are as follows: The frequency of mIPSCs decreased from 1.91+/-0.59 Hz to 0.34+/-0.09 Hz in calcium-free solution (paired t test, P=0.019, n=8), the value of mIPSCs frequency being (25.5+/-4.4)% of control. In order to rule out the effect of remaining calcium in perfusing solution we further applied calcium-free solution containing egtazic acid, ethyleneglycol-bis (beta-aminoethylether)-N,N -tetraacetic acid (EGTA) (200 nmol/L-2 mmol/L). The mIPSCs frequency changed from 1.57+/-0.57 in control to 0.89+/-0.41 Hz in calcium-free solution containing EGTA (paired t test, P=0.002, n=12), decreasing to (40.0+/-5.9)% of control. There is no statistical difference in the results between Ca(2+)-free perfusion and Ca(2+)-free solution containing EGTA (paired t test, P=0.74, n=9). When cadmium chloride (CdCl2, 100 micromol/L), a non-specific Ca(2+) channel blocker, was applied to the bath solution, the mIPSCs frequency decreased from 1.15+/-0.34 Hz in control to 0.25+/-0.09 Hz in CdCl2-containing solution (paired t test, P=0.008, n=11), reaching (29.25+/-6.1)% of control. However, the amplitude did not change much. An endoplasmic reticulum pump inhibitor thapsigargin increased the mIPSCs frequency from 0.93+/-0.19 Hz to 1.58+/-0.28 Hz (paired t test, P=0.002, n=11). The value in the latter is (214.6 +/-49.1)% of that in the former. In order to exclude the remaining calcium from the bathing solution, the mIPSCs frequency was first recorded from calcium-free solution as control (0.41+/-0.08 Hz) and then from calcium-free containing TG solution (8-16 micromol/L)(0.71+/-0.15 Hz)(paired t test, P=0.026, n=5), increasing to (175.0+/-14.6)% of control. The endoplasmic reticulum Ca(2+) store RyR agonist (ryanodine, 10-100 nmol/L) enhanced mIPSCs frequency from 1.18+/-0.40 Hz to 1.80+/-0.44 Hz with increment of (261.8+/-89.5)% (paired t test, P=0.004, n=6). However, the endoplasmic reticulum RyR antagonist (procaine, 2 mmol/L) could inhibit mIPSCs from 1.26+/-0.35 Hz to 0.43+/-0.15 Hz (paired t test, P=0.027, n=6). U73122 (40 micromol/L), a phosphalipase C inhibitor, decreased also mIPSCs frequency from 2.01+/-0.58 Hz in control to 0.92+/-0.40 Hz in U73122-containing solution (paired t test, P=0.002, n=10). Caffeine (10 mmol/L) markedly diminished mIPSCs frequency from 3.22+/-0.64 Hz to 0.15+/-0.30 Hz (paired t test, P=0.003, n=7), which is (4.6+/-2.9)% compared to control. Furthermore, in some cases the caffeine could abolish mIPSCs. Taken together, our results demonstrated that cytosolic calcium might be important for mediating the generation of mIPSCs. The cytosolic calcium could be increased by calcium influx through membrane calcium channel on presynaptic membrane, and/or by calcium released through RyR and IP(3)R in presynaptical internal store. The increased cytosolic Ca(2+) both from external solution or internal Ca(2+) stores might increase the transmitter vesicles at the presynaptic terminal, which in turn results in the increase of the mIPSCs frequency in the postsynaptic neurons.

Animals↗
PubMed2004

[The clinical value of miniature ultrasonic probes on diagnosis and treatment of digestive tract diseases].

OBJECTIVE: To investigate the clinical value of miniature ultrasonic probes (MUP) in the diagnosis and treatment of digestive tract diseases. METHODS: 537 patients who were indicated for endoscopic ultrasorography (EUS) underwent EUS with 7.5 - 20 MHz MUP and double-cavity electronic endoscope. According to the diagnoses of MUP, those patients who presented the indication of treatment were treated by endoscopic resection or surgical excision respectively, the postoperative histological results were compared with the preoperative diagnoses of MUP. A follow-up with MUP was periodically made for a few patients without endoscopic resection or surgical excision. RESULTS: Among the 537 patients the diagnosis of gastrointestinal submucosal lesions was made in the 256 cases, polyp in 56 cases, inflammatory prominence in 37 cases, extrinsic compression 53 cases, digestive tract cancer 50 cases, peptic ulcer 17 cases, cholecystolithiasis 11 cases, chronic pancreatitis in 8 cases, and achalasia 2 cases and 47 cases were diagnosed as normal, After examination of MUP, 220 patients were treated by endoscopic resection or surgical excision respectively, the postoperative histological results of 211 patients were completely consistent with the preoperative diagnosis of MUP, and diagnostic accuracy of MUP was 95.9%. The result of follow-up with MUP indicated that gastrointestinal leiomyoma, lipoma, phlebangioma and cyst were unchanged within 1 - 2 years. The patients who were treated by endoscopic resection or centesis showed no complication. CONCLUSION: EUS with MUP is a valuable method in diagnosis of gastrointestinal submucosal lesions, staging of digestive tract cancer and diagnosis of biliary-pancreatic diseases. It plays a very important role for making scientific, effective, safe and economic therapeutic plan.

Adolescent↗
PubMed2002

New, miniaturized breath analyser for applications on Earth and in space.

The present article deals with the development and application of an innovative breath analyser for metabolic stress testing and cardio respiratory measurements. The system is based on new, miniaturized ceramic gas sensors, which have the unique ability to measure simultaneously oxygen and carbon dioxide concentrations as well as flow rates. The small size of just a few millimetres allows the operation of the sensor directly in a breathing mask, minimizing dead space and breath resistance. Due to these properties and the fast response time of the measurement, it will be possible to perform a breath-by-breath analysis, in both stationary and mobile mode, with low environmental and psychological influences of the experimental circumstances to the tested person. The current development status and the most interesting technical data, experimental results, and benefits of the new breath analyser are described in the article.

Journal Article↗