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PubMed2004

Treatment of tracheal collapse with an intraluminal stent in a miniature horse.

A 7-month-old miniature horse was referred for respiratory distress. Tracheal collapse at the level of the thoracic inlet was diagnosed. An intraluminal nitinol stent was placed with endoscopic guidance. Respiratory function was restored immediately after stent placement. The main complication observed during a 14-month follow-up period was growth of granulation tissue through the stent, which was controlled satisfactorily by electrocautery performed during endoscopy with the horse standing. Treatment of tracheal collapse with an intraluminal stent is an effective, practical, and minimally invasive procedure in miniature and young equids and ponies.

Alloys↗
PubMed2005

Design of a mosquito trap support pole for use with CDC miniature light traps.

A mosquito trap support pole constructed from polyvinyl chloride and aluminum pipes was designed to hang a Centers for Disease Control and Prevention miniature light trap and dry ice container. Miniature light traps normally hang from tree branches. The trap support pole is designed to hang traps and dry ice bait in areas where no suitable trees exist.

Animals↗
PubMed1986

Undersulfated chondroitin sulfate in cartilage from a miniature poodle with spondyloepiphyseal dysplasia.

In order to determine if either the proteoglycans or collagen in the cartilagenous epiphyses of a Miniature Poodle with spondyloepiphyseal dysplasia were abnormal, the cartilage was dissociatively extracted in 4 M guanidine HCl in the presence of protease inhibitors and subjected to isopycnic cesium chloride dissociative density gradient ultracentrifugation. Dissociative extraction solubilized 97% of the uronic acid and 88% of the protein. Uronic acid distributed anomalously in the density gradient in that about 1/3 was recovered in each of the D1 (1.58 g/ml), D2 (1.49 g/ml) and D3 (1.44 g/ml) fractions. Proteoglycans in the D1, D2 and D3 fractions also eluted from Sepharose CL-2B columns in a manner indicative of monomers of a smaller apparent hydrodynamic size than those from normal canine growth plate or articular cartilage. D1, D2 and D3 monomers subjected to the sodium borohydride reaction followed by chromatography on a Sepharose CL-6B column yielded glycosaminoglycan chain molecular weights of 10,200 (D1), 7600 (D2) and 6200 (D3). High pressure liquid chromatography on a Whatman Partisil 10PAC column of the chondroitinase AC II digests of D1, D2 and D3 fractions revealed that 60% of the D1, 81% of the D2 and 88% of the D3 unsaturated disaccharides eluted in the delta DiOS-delta DiHA position. Subsequent HPLC of the unsaturated disaccharides on the Hypersil APS column resulted in the recovery of 97% of the nonsulfated unsaturated disaccharides in the delta DiOS position. Associative extraction in 0.5 M guanidine followed by associative gradient ultracentrifugation resulted in the recovery of 27% of the uronic acid in the aA1 and 47% in the aA2 fractions. Two dimensional SDS gel electrophoresis of the CNBr peptides of the collagen isolated by pepsin digestion and 0.9 M NaCl precipitation revealed type II collagen. This study has demonstrated that spondyloepiphyseal dysplasia in a Miniature Poodle is characterized by cartilage containing undersulfated chondroitin sulfate proteoglycan.

Animals↗
PubMed2003

Comparative reduction of Norwalk virus, poliovirus type 1, F+ RNA coliphage MS2 and Escherichia coli in miniature soil columns.

Norwalk-like viruses (NLVs) are important agents of waterborne illness and have been linked to several groundwater-related outbreaks. The presence of human enteric viruses, in particular the presence of NLVs, is difficult to detect in the environment. Consequently, surrogate organisms are typically used as indicators of viruses from faecal contamination. Whether traditional bacterial indicators are reliable indicators for viral pathogens remains uncertain. Few studies have directly compared mobility and reduction of bacterial indicators (e.g. coliforms, Escherichia coli) and other surrogate indicators (coliphages) with pathogenic human viruses in soil systems. In this study the mobility and comparative reduction of the prototype NLV, Norwalk Virus (NV), was compared to poliovirus 1 (PV1), a bacterial indicator (E coli, EC) and a viral indicator (coliphage MS2) through miniature soil columns. Replicate, 10 cm deep, miniature columns were prepared using three soils representing a range of soil textures (sand, organic muck, and clay). Columns were initially conditioned, then incubated at 10-14 degrees C, dosed twice weekly for 8 weeks with one column pore volume of virus-seeded groundwater per dose, followed by 8 weeks of dosing with one column pore volume per dose of unseeded, simulated rainwater. Columns were allowed to drain after each dosing until an effluent volume equivalent to an applied dose was collected. Column effluents and doses were assayed for all viruses and EC. Rapid mobility with minimal reduction was observed for all organisms in the sand. Similar reductions were observed in organic muck for most organisms but NV showed a greater reduction. No organisms were shown to pass through the clay columns. Elution of viruses, in particular PV1, from the columns was gradual. After cessation of microbe dosing, E. coli was less detectable than viruses in column effluents and, therefore, unreliable as a virus indicator.

Aluminum Silicates↗
PubMed2003

Cerebellar abiotrophy in a miniature schnauzer.

A 3.5-month-old miniature schnauzer was presented for signs of progressive cerebellar ataxia. Necropsy revealed cerebellar abiotrophy. This is the first reported case of cerebellar abiotrophy in a purebred miniature schnauzer.

Animals↗
PubMed2004

[Modulation of miniature inhibitory potentials in motoneurons of the turtle spinal cord by group II metabotropic glutamate receptors].

The role of group II metabotropic glutamate receptors (mGluRs) in modulation of inhibitory synaptic activity was studied by intracellular recording of motoneuron miniature inhibitory spontaneous postsynaptic potentials (mIPSPs) in isolated lumbar segments of the turtle spinal cord in the medium containing TTX, CNQX, AP-5. The ratio of mIPSPs with fast and slow kinetics (83% vs 17%) is in accordance with the ratio shown for glycine- and GABA-mediated IPSP or IPSCs (Jones et al., 1988; Gao et al., 2001). In the majority of investigated motoneurons, the selective group II mGluRs antagonist EGLU (100-250 microM) increased the frequency of mIPSPs by 106.6 +/- 74.4% (n = 9) without affecting average amplitude, suggesting a presynaptic site of mGluRs action providing for the transmitter release reduction. The analysis of EGLU action on mIPSPs with different time courses (selection by half-width) showed that the frequency of inhancement of miniature inhibitory activity is caused by predominantly short-duration mIPSPs (ba 84.0 +/- 18.2%; n = 9), which are probably glycineergic. However, EGLU did not influence the mIPSPs frequency under condition of GABA-receptor blockade by bicuculline (20 microM). This fact suggest that group II mGluRs could modulate glycinergic transmission to the turtle spinal motoneurons on the necessary condition that GABergic system is active.

Animals↗
PubMed2005

Rat cardiopulmonary bypass model: application of a miniature extracorporeal circuit composed of asanguinous prime.

A clinically relevant rat cardiopulmonary bypass (CPB) model would be a valuable tool for investigating pathophysiological and therapeutic strategies on bypass. Previous rat CPB models have been described in the literature; however, they have many limitations, including large circuit surface area, the inability to achieve full bypass, and donor blood requirements for prime. Therefore, we have established a rat CPB model designed to overcome these limitations. The miniature circuit consisted of a filtered reservoir, heat exchanger, membrane oxygenator (surface area = 0.02 m2) with a static priming volume of 2.8 mL, and an inline blood gas monitor. The circuit was primed with 9.5+/-0.5 mL of crystalloid solution and CPB was established on male Sprague-Dawley rats (430-475 g, n = 5) by cannulating the left common carotid artery and the right external jugular vein. The animals were placed on CPB at full flow (111+/-13 mL/kg/ min) for 1 hour and were monitored for and additional 2 hours after the CPB procedure. Hemodynamics, hemoglobin concentration (Hb), and blood gases were analyzed at three time intervals: before, during, and after CPB. The circuit performance was evaluated according to prime volume, compliance, hemodynamic parameters, and gas and heat exchange as described by modified AMMI standards. Data are expressed as mean+/-SD and a repeated-measures analysis of variance with post-Hoc test was used for data comparison between the three time intervals. The ratio of oxygenator surface area to subject body weight for this model is comparable with that of current human adult CPB practice (0.05 m2/kg vs 0.057 m2/kg) Full CPB was achieved and we observed clinically acceptable PaO2, PaCO2, and SvO2 values (209+/-86 mmHg, 25+/-2 mmHg, 78+/-8%, respectively) while on CPB. The use of asanguinous prime did produce statistically significant Hg reduction (15.7+/-0.76 vs. 9.2+/-0.59 g/dL) comparable with clinical practice. No statistically significant differences between pre- and post-CPB hemodynamics and blood gases were found in our study. We have established a miniature circuit consisting of asanquineous prime for a rat CPB model that maintains clinically acceptable results regarding hemodynamic parameters, blood gases, and hemodilution. This model would be valuable for further use in clinically relevant research studies.

Animals↗
PubMed1992

Application of a continuous ventricular function monitor with miniature cadmium telluride detector to patients with coronary artery bypass grafting.

A continuous ventricular function monitor with a miniature cadmium telluride detector was evaluated and applied to patients with coronary bypass surgery (CABG). Ejection fraction (EF) at rest and change in EF from rest to exercise and postexercise (Y) measured with the device correlated with that of the gamma camera (X) (Y = 0.86x + 6.8(%), r = 0.87, n = 110, p less than 0.001, and Y = 0.96x + 0.4(%), r = 0.90, n = 37, p less than 0.001 respectively). Left ventricular function during and after supine ergometer exercise was monitored in 54 patients before and after CABG. The EF change from baseline to peak exercise improved from -5.9% +/- 8.9% before CABG to 7.2% +/- 7.9% after CABG (p less than 0.001). In all patients but two, a rapid EF increase just after exercise over baseline EF was observed. This EF "overshoot" during recovery increased from 11.5% +/- 6.5% to 16.4% +/- 6.0% (p less than 0.001) after CABG. The time from the cessation of exercise to EF overshoot decreased from 153 +/- 80 sec to 76 +/- 49 sec (p less than 0.001) after CABG. The continuous ventricular function monitor with a miniature cadmium telluride detector is able to measure EF reliably. Following successful aortocoronary bypass, EF response during exercise improved and the EF overshoot in the recovery phase became faster and higher.

Cadmium↗
PubMedDate not supplied

In vitro and in vivo evaluation in dogs of a miniaturized glucose sensor.

A miniaturized glucose sensor was developed, consisting of a platinum wire entirely coated with teflon, except for a 1 mm section near its extremity where glucose oxidase is immobilized. The in vitro sensitivity to glucose of the sensors was 2.3 +/- 0.4 nA/mM, mean +/- SEM (n = 23). These sensors were implanted in the subcutaneous tissue of normal beagles. Two consecutive glucose infusions (15-30 mg/kg/min) were performed. The current generated by the sensor was used for calculation of the sensitivity coefficient (SC) (nA/mM), and the background current in the absence of glucose (lo) (nA). These parameters were used for determination of the apparent subcutaneous glucose concentration. The in vivo sensitivity was less than the in vitro sensitivity (0.5 +/- 0.1 vs. 2.2 +/- 0.2; n = 12 comparisons; p less than 0.01). Stability of sensor function was demonstrated by the absence in variation of SC and lo, calculated from the different plateaus obtained during the glucose infusions. This study provides a simple method for evaluating in vivo the function of a miniaturized sensor implanted in subcutaneous tissue.

Animals↗
PubMed1991

[Extremely low birth-weight infant with hydrocephalus; management of hydrocephalus using a miniature Ommaya's reservoir].

Use of the miniature Ommaya's reservoir in the treatment of extremely low birth-infant (under 1,000 mg) with hydrocephalus was studied in a series of five patients. The reservoir has a small-caliber with a 3 cm ventricular catheter. For these infants, this miniature Ommaya's reservoir is extremely useful for protection of the cortical mantle until a definitive procedure can be carried out after increase of body weight. The clinical course in five cases are summarized.

Cerebrospinal Fluid Pressure↗
PubMed1990

[Results of the operation for creating "miniature stomach" in the treatment of alimentary-constitutional obesity].

The article analyses the results of surgical treatment of alimentary-constitutional obesity in 207 patients by means of operation for formation of a "miniature stomach". Total postoperative mortality was 2.4%. This index was 4.2% in the period when the method was mastered and 0.89% for the next 112 operations. It is shown that the operation for formation of a "miniature stomach" leads to a significant and stable loss of body weight, recovery from concomitant diseases or essential diminution of their severity, it alters the patients' life for the better and makes it possible for many of them to resume work.

Adolescent↗
PubMedDate not supplied

Miniature environments and subjective estimates of time.

A recent review of a century of studies describes the different conditions in which subjective estimates of time deviate, sometimes considerably, from clock time. With reference to experimental data published a few years ago, showing that prolonged observation of a scene in miniature induces the observer to ascribe durations contracted by the scale factor to events imaginable therein, it is demonstrated that a simple comparison with the time of the experimenter does not always reveal all the effects obtainable from the data. Avoiding questions of interpretation belonging to the field of psychology, the author applies the physical law of time contraction to a miniaturized scene to provide a time reference dependent on the scale factor, to be exact, proportional to its square root.

Environment, Controlled↗
PubMedDate not supplied

Evaluation of a miniature blood glucose sensor.

A miniature version of the electrocatalytic glucose sensor has been designed and fabricated with thick-film metalization technology. The in vitro stability tests of the sensor were performed in buffered saline, human plasma ultrafiltrate, and bovine plasma. For bovine plasma studies the sensor was directly coated with a semipermeable ethylene vinyl alcohol (EVAL) membrane. To stabilize the activity of the sensing platinum electrode, a fast-pulsing reactivation method was applied. Good performance of the continuously operating sensor was achieved in buffer (10% stability of the baseline current within 12 days) and human ultrafiltrate (10% stability of the baseline current and 5% stability of the sensitivity within 7 days). However, for measurements in plasma a slow degradation of the sensor's sensitivity (approximately 10% per day) was observed. These results indicate that when a proper screening membrane is provided the continuous glucose monitoring of body fluids with the miniature sensor is possible for at least 7 days.

Animals↗
PubMedDate not supplied

Characterization of the hepatic microsomal mixed-function oxidase enzyme system in miniature pigs.

Hepatic microsomal protein, cytochrome P-450, UDP-glucuronyltransferase, ethylmorphine demethylase, aniline hydroxylase, and aryl hydrocarbon hydroxylase levels were measured in the 2-, 4-, 5-, 6-, and 8-month-old Hanford miniature pig. The activities or concentrations of all of the liver parameters measured had apparently reached their adult plateau level by 2 months of age. The use of the miniature pig in toxicology research programs is discussed.

Aging↗
PubMed1986

Prekallikrein deficiency in a family of miniature horses.

Two sibling miniature horses, a male and a female, had a normal 1-stage prothrombin time and a prolonged activated-partial thromboplastin time (APTT). The addition of as little as 5% of a normal equine plasma pool to the plasma samples of both horses shortened their prolonged APTT to within normal limits. Coagulation factor analysis revealed deficiencies in factor XII (12 and 13 U/dl, control population 77 to 128 U/dl), when determined with a feline factor XII-deficient plasma substrate, but normal concentrations (119 and 96 U/dl) when a human factor XII-deficient plasma substrate was used. Deficiencies of another factor, prekallikrein, were detected with a human prekallikrein-deficient plasma substrate (16 and 6 U/dl, control population 70 to 173 U/dl). Other intrinsic coagulation factors were present in normal concentrations. The APTT was measured with plasma from the 2 horses after various incubation periods (1 to 15 minutes) with a contact activator before the addition of Ca ions. With incubation times of greater than or equal to 10 minutes, the APTT of both horses were essentially the same as that of the normal equine plasma pool. Several family members of the 2 prekallikrein-deficient miniature horses appeared to be heterozygous carriers of the prekallikrein deficiency.

Animals↗
PubMed1979

Transplantation in miniature swine. V. Characterization of Ia antigens.

The complexity of the I region analog associated with the MHC of miniature swine has been probed by sequential antibody precipitation studies of Ia antigens. Treatment of solubilized lymphocyte preparations from MSLA homozygotes of the DD haplotype with excess AA anti-DD alloantiserum led to precipitation of only a portion of the total Ia antigens, as determined by secondary precipitation of the remaining material with CC anti-DD serum. The presumed I region of miniature swine must therefore code for more than one Ia antigen-bearing polypeptide chain. In addition, certain mouse alloantisera that had previously been shown to react with rat Ia antigens were tested for reactivity with swine Ia antigens. Anti-Iak mouse alloantisera precipitated Ia molecules from every swine extract tested, regardless of MHC type, precluding genetic mapping studies. However, sequential precipitation studies demonstrated that the cross-reactive mouse alloantisera reacted only with a subclass of swine Ia antigens, again suggesting genetic complexity of the pig Ia locus.

Animals↗
PubMed1986

Full-field electroretinograms in miniature poodles with progressive rod-cone degeneration.

Full-field electroretinograms (ERGs) were recorded between the ages of 4 and 34 months from 8 miniature French poodles with inherited progressive rod-cone degeneration (PRCD) and from 11 normal miniature poodles. Three stages of retinal function were observed in the affected dogs, although the ages of transition from one stage to the next were variable among dogs. Rod and cone ERGs were normal in amplitude in the first stage, rod ERGs were reduced in amplitude and cone ERGs were normal in the second, and rod ERGs were extremely reduced in amplitude or nondetectable and cone ERGs were reduced in amplitude in the third. On average, these poodles with PRCD lost 7.2% of remaining rod amplitude per month and 2% of remaining cone amplitude per month. Affected poodles had normal rod and cone b-wave implicit times over all three stages, in contrast to humans with the early stages of progressive forms of retinitis pigmentosa who have delayed rod and/or cone b-wave implicit times.

Animals↗
PubMed1972

50-Chromium labeled erythrocyte half-time disappearance from adult Sinclair (S-1) miniature swine.

Half-time disappearance of (51)Cr-labeled erythrocytes from 20 adult miniature swine was measured. Seven males and 13 females from 388 to 418 days of age, having a mean weight of 55kg were studied. Five ml of blood collected from each animal were labeled with 75 microCi (51)Cr at room temperature for 60 to 90 min. Following injection of the labeled erythrocytes into each animal, blood samples were collected every four to six days. Specific activity was measured and half-time disappearance determined by linear regression. The results were compared with values obtained from the same animals tested at two earlier ages. No significant (P <0.05) difference in erythrocyte half-time disappearance was detected between males and females at the three different ages. Mean (+/-SEM) erythrocyte half-time disappearance values were: 20 to 46 days of age, 19.58 (+/-0.59) days; 79 to 109 days of age, 23.56 (+/-1.18) days; and 388 to 418 days of age, 22.35 (+/-0.72) days. A significant (P <0.01) difference in erythrocyte half-time disappearance was found between the miniature swine tested at 20 to 46 days of age and those tested at either 79 to 109 or 388 to 418 days of age. No significant (P <0.05) difference in erythrocyte half-time disappearance was found between the two older age groups.

Animals↗