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PubMed2000

Dental and craniofacial findings in eight miniature schnauzer dogs affected by myotonia congenita: preliminary results.

Myotonia is a clinical sign characterized by the delay of skeletal muscle relaxation following the cessation of a voluntary activity or the termination of an electrical or mechanical stimulus. Recently, Miniature Schnauzers with myotonia congenita associated with defective chloride ion conductance across the skeletal muscle membrane were identified. Congenital myotonia in these dogs appears to follow an autosomal recessive mode of inheritance. Craniofacial and dental findings of eight Miniature Schnauzer dogs with myotonia congenita are described in the present paper. These findings include: delayed dental eruption of both deciduous and permanent dentition: persistent deciduous dentition; unerupted or partially erupted permanent teeth: crowding and rotation of premolar and or incisor teeth: missing teeth: increased interproximal space between the maxillary fourth premolar and first molar teeth: decreased interproximal space between the maxillary canine and lateral incisor teeth: inability to fully close the mouth due to malocclusion: distoclusion: and, decreased mandibular range of motion. A long narrow skull with a flattened zygomatic arch and greater mandibular body curvature were also consistent findings in the affected dogs. The small number of dogs studied prevents conclusive statements about the origin of these abnormalities, however it is interesting that only 1 of 45 unaffected Miniature Schnauzer dogs showed similar traits.

Animals↗

PubMed2005

Complications after cryosurgery with new miniature cryoprobes in long hollow bones: an animal trial.

BACKGROUND: In vitro studies show that new miniature cryoprobes are suitable for cryoablation of bone tissue. The aim of this animal trial on 24 sheep was to examine the perioperative complications, particularly the danger of embolism, of cryoablation when using miniature cryoprobes. METHODS: Cryoablations with 2 freeze-thaw cycles each were carried out in the epiphysis of the right tibia and the metaphysis of the left femur. Pulmonary artery pressure (PAP) and central venous pressure (CVP) were measured. Throughout the intra- and perioperative phase, heart rate and oxygen saturation by pulse oxymetry, blood gas and electrolytes were monitored regularly. Postoperative complications were examined up to 24 weeks postoperative. RESULTS: As result, no significant increase of PAP, CVP or heart rate were observed. Blood gases were unremarkable, with pO2 and pCO2 remaining constant throughout the operation. Regarding pH, standard bicarbonate and base excess, only a non-significant shift towards a slight acidosis was seen. There was a mean hemoglobin decrease of 0.5 g/dl. One animal showed postoperative wound infection and wound edge necrosis. No major peri- and postoperative complications associated with cryosurgery of bone were observed, especially regarding clinically relevant pulmonary embolism. CONCLUSION: Surgery with new types of miniature cryoprobes appears to be a safe alternative to or a complement to conventional resection of abnormal bone tissue.

Animals↗

PubMed1991

Comparative vascular anatomy of the hip of the miniature dog and of the normal-size mongrel.

In order to investigate the aetiology of Perthes' disease in the dog the author has conducted a comparative anatomical study of the vascular system of the femoral heads in miniature dogs and in normal-size mongrels. The study was made in five three-months old miniature dogs and five age-matched normal-size mongrels, in which the epiphyseal plate of the femoral head was still open. The most distinct difference between the two species was in the channel of the superior retinacular vessels. In miniature dogs, these vessels go through the shallow neck and appear as a "suspended bridge". In normal-size mongrels they go through the deep fossa of the femoral neck and appear to be very rigidly stable. Although foveolar vessels in the round ligament were present in both species, no vessels were found in either species reaching the epiphysis by penetrating the articular cartilage at this stage of development.

Animals↗

PubMed1979

The disposition of [14C]iprindole in man, dog, miniature swine, rhesus monkey and rat.

1. Absorption of a single oral dose of [14C]iprindole was rapid in rats, rhesus monkeys, miniature swine, dogs and human volunteers. In all species except the rat, most of the radioactivity in the blood resided in the plasma. Small amounts of unchanged iprindole were detected in the plasma of rats and rhesus monkeys but not in man and miniature swine. 2. Radioactivity was excreted mainly in the urine of man, miniature swine and rhesus monkey, but in the faeces of rat and dog. 3. Urinary radioactivity was associated with basic (free and conjugated), acidic and highly polar, water soluble metabolites. At least 20 metabolites as well as small amounts of unchanged drug were detected in the basic fractions of each species' urine. 4. Many of these metabolites were common to all species; however, qualitative as well as quantitative differences were apparent. Mass-spectrometric analysis of several metabolites indicated N-demethylation and oxidation of the alicylic ring or a combination of both pathways.

Animals↗

PubMed1993

Sonographically guided laparoscopy and mediastinoscopy using miniature catheter-based transducers.

Miniature ultrasound transducers (12.5 MHz) housed in 9 Fr catheters were passed through a laparoscope or mediastinoscope to image a variety of normal and abnormal structures within the peritoneal cavity and mediastinum in 20 patients. These transducers made it possible to visualize the gallbladder and bile ducts and evaluate for the presence of stones, to detect masses and provide guidance for their aspiration or biopsy, and to image the internal structures of the ovary and fallopian tube. In addition, these miniature transducers were used to locate such normal vital structures as blood vessels, thereby allowing the surgeon to decide on the best approach for dissection during mediastinoscopy. During conventional surgery, the surgeon or gynecologist can palpate an area of abnormality not directly visualized. However, during laparoscopy and mediastinoscopy direct palpation is not possible. Therefore, it is important to find another method to determine what structures lie beneath the visualized surface. These miniature ultrasound transducers appear to offer a means for making such determinations.

Adult↗

PubMed1975

Restraint, venipuncture, endotracheal intubation, and anesthesia of miniature swine.

Miniature swine are useful as experimental animals for investigations involving major surgical procedures, provided that proper restraint and anesthetic methods are employed. The methods and drugs described herein are not intended to be all-inclusive but rather those found most applicable to a wide variety of studies with miniature swine at this laboratory. This report is intended primarily to guide those unfamiliar in handling miniature swine during initiation of studies with that species. For chemical restraint during minor procedures, diazepam, at a dose of 5.5-8.5 mg/kg im, has become the drug of choice. For surgical anesthesia, optimal results have been obtained using thiamylal sodium iv for induction of anesthesia and maintained by 0.5-1.5% halothane administered via an endotracheal cannula. Pentobarbital sodium may be used to produce surgical anesthesia but is generally unsatisfactory except for terminal procedures. Electroanesthesia, even with concomitant use of tranquilizing drugs, is difficult to control and results in very poor muscle relaxation.

Anesthesia↗

PubMed2001

A calcium-dependent feedback mechanism participates in shaping single NMDA miniature EPSCs.

NMDA receptors (NMDARs) are highly calcium-permeable and are negatively regulated by intracellular calcium during prolonged exposure to agonist. We have investigated whether calcium-mediated feedback occurs during transient exposure to glutamate during single synaptic events. Examination of miniature EPSCs (mEPSCs) indicated that the decay kinetics of the NMDAR component was markedly slowed by the intracellular perfusion of exogenous calcium buffers (BAPTA or Fluo-3). In contrast, the AMPA receptor component of the miniature EPSC was unaffected. Slow on-rate calcium buffers, such as EGTA, did not alter kinetics of the NMDAR component of the mEPSC. Addition of exogenous fast calcium buffers did not slow the decay kinetics of glutamate-evoked currents mediated by NR1/NR2A heteromers expressed in HEK 293 cells, suggesting that the effect we observed in neurons may be specific to processes associated with synaptically activated receptors. Trial-to-trial amplitude variability of miniature calcium transients mediated by NMDARs increased with the injection of exogenous calcium buffers, suggesting that the amplitude of synaptic calcium transients are maintained at a rather constant level by a calcium-mediated feedback mechanism.

Aniline Compounds↗

PubMed2001

Hair diameter diversity: a clinical sign reflecting the follicle miniaturization.

BACKGROUND: The degree of androgenetic alopecia is generally evaluated either by global clinical scales or time-consuming methods like phototrichogram or histological studies. We describe a new clinical and reliable scoring method based on hair diameter diversity. OBSERVATIONS: (1) The clinical macroscopic scoring we propose for hair density was significantly correlated with Hamilton classification and with histological hair density. (2) Diversity in hair diameter was the main and most accurate clinical parameter linked to follicle miniaturization. (C) The anagen-telogen ratio decreased in parallel with the decrease in clinical hair density score. CONCLUSIONS: Considering that hair follicle miniaturization is the key point during androgenic alopecia onset and development, diversity in hair diameter represents an important feature to consider as an accurate clinical sign reflecting hair follicle miniaturization. Moreover, diversity in hair diameter seems to be an easily accessible and reliable parameter that should be taken into consideration for further characterization of hair disorders. By itself, we believe that this clinical feature constitutes a new tool of substantial help for the diagnosis and management of androgenic alopecia.

Adult↗

PubMed1975

Hypotrichosis in Miniature Poodle siblings.

Progressive hypotrichosis was detected in 2 silver male Miniature Poodle siblings at 5 weeks of age. A male and 2 female siblings had normal black coats. The sire, a 3-year-old black Miniature Poodle, and the dam, a 2-year-old silver Miniature Poodle, also had normal coats. Microscopically, the hypotrichotic skin had accumulations of keratotic debris and melanin in dilated hair canals and melanin deposits in and around inactive hair bulbs. Sex-linked or sex-limited inheritance may have been involved, inasmuch as both affected dogs were males.

Alopecia↗

PubMed1992

Fecalith impaction in four miniature foals.

Four miniature foals admitted with signs of progressive nonresponsive abdominal pain and no fecal production had fecalith impaction of the small colon. Duration of clinical signs ranged from 10 hours to 5 days. Removal of the fecalith via small colon enterotomy was a successful treatment in all 4 cases. Miniature foals may be predisposed to fecalith impaction of the small colon. If a miniature foal has signs of progressive nonresponsive abdominal pain, fecalith impaction needs to be considered. Surgical correction may be required.

Animals↗

PubMed2005

[Clinical equivalence trial of UROCALUN miniaturized tablet in patients with upper urinary tract stone disease].

We performed a clinical trial on patients with upper urinary tract stone disease (renal stone disease) to prove the clinical equivalence as the target for removal of renal stones between the new formulation (miniaturized tablet) and the conventional formulation (capsule) of UROCALUN. The clinically effective rate of both formulations was the same at 70% (28 of 40 cases), and it was suggested that these two formulations possess the same clinical efficacy. Adverse drug reactions were observed in 10.0% (4 of 40 cases) with the tablet and 5.0% (2 of 40 cases) with the capsule. There were no significant differences between the two formulations in the incidence of adverse drug reactions, and there were no clinically significant safety problems. In the questionnaire survey for patients about medication compliance, we found that the patients felt the miniaturized tablets were much easier to swallow than the conventional formulation. In conclusion, it is suggested that the miniaturized tablet contributes to improve the medication compliance for patients and thus it is expected to improve the clinical efficacy.

Administration, Oral↗

PubMed1986

Comparison of an experimental updraft ultraviolet light trap with the CDC miniature light trap and biting collections in sampling for Anopheles albimanus in Haiti.

Three methods of capturing Anopheles albimanus mosquitoes were compared during a field study in four villages in northern Haiti. Updraft ultraviolet (UV) light traps proved to be more effective than biting collections, regardless of season or whether the tests were done indoors or outdoors. Biting collections were in turn more effective than the Centers for Disease Control (CDC) miniature light traps. Updraft UV light traps and biting collections yielded more An. albimanus outdoors than indoors; the reverse was found for the CDC miniature light traps. The updraft UV light traps caught An. albimanus on 86% of the occasions used outside and 75% of the occasions inside. The biting collections were equally as successful as the traps in catching mosquitoes outside but caught An. albimanus only on 64% of the occasions when used inside houses. The CDC miniature light traps were successful in collecting An. albimanus on 33% of the occasions outside and 60% of the occasions inside.

Animals↗

PubMed1972

51-chromium labeled erythrocyte half-time disappearance from miniature swine.

Half-time disappearance of (51)Cr-laeled erythrocytes was studied in 39 Sinclair miniature swine at 20 to 46 days of age and again at 79 to 109 days of age. Mean erythrocyte half-time disappearance, disregarding age, was 21.29 (+/-0.77) days for males and 22.04 (+/-0.81) days for females. The half-time difference between males and females was not statistically significant (P<0.05). At 20 to 46 days of age the mean erythrocyte half-time disappearance was 19.56 (+/-1.41) days. The same pigs, tested at 79 to 109 days of age, had a mean erythrocyte half-time disappearance of 23.95 (+/-1.94) days. There was a significant difference (P<0.01) in erythrocyte half-time disappearance from miniature swine as the result of age and also for age within sex. The grand mean erythrocyte half-time disappearance, for all the miniature swine tested, was 21.67 (+/-0.54) days. The estimate of heritability was 0.61 for dam effect at 20 to 46 days of age and 0.06 at 79 to 109 days of age. Sire estimate of heritability was 0 at both age groups. It was concluded that the large heritability coefficient found only for dam component in young nursing pigs was the result of maternal environment rather than additive genetic variance.

Age Factors↗

PubMed1981

[Miniature potentials in fast and slow muscle fibers in the locust].

The miniature excitatory postsynaptic potentials were studied in the fast and slow fibres of Locusta migratoria by means of intracellular microelectrodes. Statistical analysis indicated that the spontaneous transmitter release can be predicted by the negative binomial formula with a 85% reliability. It shows that there is certain mutual interaction between the processes responsible for the spontaneous release of the transmitter from locust nerve terminals. In the calcium-free solutions frequency of miniature potentials was reduced to about 83.5% in the fast muscle fibres and to about 96.3% in the slow muscle fibres. A study of Mg++ effect on frequency of miniature potentials showed that 10 mM Mg++ reduced the frequency to about 75% in the fast muscle fibres and to about 90% in the slow ones. The conclusion is drawn that in the fast and slow muscle fibres the nerve terminals possess different sensitivity to the changes in ionic composition of the environment.

Animals↗

PubMed1984

Clinical biochemical and hematologic values of the American Miniature Horse: reference values.

Sixteen clinical biochemical determinations and 13 hematologic measurements were performed on 49 healthy American Miniature Horses of mixed age and both sexes. Serum triiodothyronine and thyroxine values were also determined. Serum biochemical test results from American Miniature Horses compared favorably with values for full-sized horses, whereas differences in hematologic test results were noticed between American Miniature Horses and full-sized horses.

Animals↗

PubMed1978

Use of vectorcardiography for the detection of +Gz-related cardiac pathology in miniature swine.

Vectorcardiograms were recorded from anesthetized, adult miniature swine 1-2 weeks before high sustained +Gz exposure and 2-6 h after exposure. Each +Gz run consisted of one 60-s exposure, respectively, to 3, 5, 7, and 9 +Gz, with 3 min rest between each +Gz plateau. The full range, from severe to minor, of +Gz-induced cardiac pathology was observed in this group of miniature swine. In spite of the large variation in the amount and degree of cardiac pathology, there were no post-exposure vectorcardiographic changes which might be diagnostic of +Gz-induced cardiac pathology. The results of this study indicate that vectorcardiography, performed after +Gz exposure, is not a reliable technique for detecting the presence of +Gz-induced cardiac pathology in miniature swine.

Aerospace Medicine↗

PubMed1983

Biometry and clinical characteristics of congenital cataracts and microphthalmia in the Miniature Schnauzer.

Forty-two Miniature Schnauzer pups and adults with congenital cataracts and microphthalmia were evaluated by serial ophthalmic examinations, slit lamp biomicroscopic photography, and A-scan ultrasonography. The cataracts were evident when the eyelids opened at 2 weeks, affecting predominantly the lens nucleus and posterior cortex. Lenticonus was evident in 19% of the cataractous lenses. Progression of the cataracts was variable and related to involvement of the equatorial and posterior cortices. Lens-induced uveitis developed in some adult dogs with advanced hypermature cataracts. The globe and lens were smaller than normal in the cataractous eyes, as ascertained by A-scan ultrasonography. Age-matched comparisons of clear lens carrier Miniature Schnauzers and normal Beagles with the cataractous Miniature Schnauzers indicated affected globes and cataractous lenses were reduced 10% to 20% in their anteroposterior lengths. The microphthalmia appeared related to the congenital microphakic cataract.

Animals↗

PubMed1980

The importance of myocardial perfusion in the pathogenesis of the cardiac pathology associated with +Gz exposure in miniature swine.

Minor cardiomyopathy has been associated with exposure of miniature swine to levels of high sustained +Gz which can be attained routinely in new USAF high-performance aircraft. One possible cause of these lesions is total or regional myocardial ischemia. To test this hypothesis, regional coronary blood flow was measured with the radiolabeled microsphere technique in chronically instrumented miniature swine during 60-s exposures to +3Gz, +5Gz, or +7Gz. Acceleration exposure resulted in detectable left ventricular subendocardial hemorrhage in 1 of 5 animals exposed to +3Gz, in 7 of 8 animals exposed to +5Gz and in all 8 animals exposed to +7Gz. All levels of +Gz stress caused 2-3 fold increases in coronary blood flow. The regional distribution of coronary blood flow during +Gz was similar to that under resting control conditions as long as aortic diastolic pressure was maintained. There was no clear evidence of total or regional myocardial ischemia during +Gz or of any relationship between regional coronary blood flow and the presence of subendocardial hemorrhage. It is concluded that myocardial ischemia is not a primary factor in the pathogenesis of the cardiac lesions associated with the exposure of miniature swine to +Gz stress.

Acceleration↗