Atypical lateral tracheal collapse in a Yorkshire terrier.

A 10-month-old, neutered female Yorkshire terrier was presented with a 6-month history of inspiratory dyspnoea, coughing and exercise intolerance. Tracheoscopy revealed marked lateral-to-lateral fixed collapse of the cervical trachea and mild collapse of the thoracic trachea. Surgical exploration revealed a marked reduction in lateral tracheal width and multiple malformed tracheal rings. Placement of extraluminal ring prostheses around the cervical trachea resulted in widening of the tracheal diameter and an immediate improvement in clinical signs. 6 years postoperatively the patient was reported to have an excellent quality of life with complete resolution of clinical signs.

Invasive group B streptococcal disease in Maryland nursing home residents.

Between 1991 and 1995, among 999 nonpregnant adult Maryland residents with group B Streptococcus (GBS) isolated from a normally sterile site, 84 resided in nursing homes (NHs). The age-adjusted annual incidence of GBS infection (per 100,000 population) among those > or = 65 years old was 72.3 for NH residents and 17.5 for community residents (relative risk, 4.1; P < 0.001). Thirty-four case patients resided in 11 NHs with > or = 2 cases; 1 NH had 8 case patients within 22 months. Six of 8 case patients from 3 NHs had serotype V GBS. Molecular subtyping of several isolates identified 2 case patients in 1 NH with identical subtype patterns. NH residents have a markedly higher incidence of invasive GBS than do community residents > or = 65 years old and may serve as a target group for immunization when GBS vaccines become available. Further evaluation of intra-NH transmission of GBS is warranted.

Role of surgical intervention in the management of crotaline snake envenomation.

Crotaline venoms produce various toxic effects. Although these are most commonly treated with specific antivenoms, surgical management of snakebite has also been practiced for many years. Surgical approaches to pit viper envenomation include incision or excision of the bite site, fasciotomy, and digit dermotomy. The evidence regarding each of these procedures is sparse; however, incision or excision of the bite site are difficult to advocate. Fasciotomy and digit dermotomy may be appropriate in carefully selected patients.

Studies on the measurement of phospholipase A2 (PLA2) and PLA2 inhibitor activities in ram semen.

Extraction with Tris-citrate or Tris-NaCl-EGTA improved the yield of phospholipase A2 (PLA2) from ram semen by 40-50 fold over the previously recommended method of extraction by dilute (0.18 N) sulphuric acid. The enzyme activity in the citrate extract deteriorated more rapidly than in Tris-NaCl-EGTA. The semen PLA2 activity was optimum at pH 8.0, heat sensitive at 70 degrees C for 30 min, activated by Ca2+ (although approximately 60% activity was also found in the absence of calcium) and did not exist as a pro-enzyme. The semen PLA2 activity was equally distributed among the sperm and seminal plasma (SP) components of ram semen. However, the low levels of PLA2 activity in the SP of vasectomised rams tend to suggest that PLA2 in the SP fraction may have originated from testicular or epididymal secretions or leakage, from sperm. PLA, in sperm exists as a large molecular weight aggregate, whereas in SP it is present as a smaller aggregate. In addition to PLA2, semen also contained PLA2 inhibitor activities. Inhibition was observed against PLA2s from bee venom, pig pancreas and oviductal extracts. The inhibitory activity is presumed to be due to a large molecular weight protein as the inhibitor activity was not extracted in a chloroform:methanol (2:1; v/v) mixture, it was non-dialysable, precipitated by 10% trichloroacetic acid and destroyed by proteases. The inhibitor activity was distributed in various molecular weight fractions of sperm, SP and SP from vasectomised rams.

Effect of oral creatine ingestion on parameters of the work rate-time relationship and time to exhaustion in high-intensity cycling.

The relationship between work rate (W) and time to exhaustion (t) during intense exercise is commonly described by either a hyperbolic function (NLin), t= W'/(W-Wcp), or by its linear equivalent (LinW) Wlim=W' + Wcp(t). The parameter Wcp (critical power) has been described as an inherent characteristic of the aerobic energy system, while W' has been shown to be a ralid estimate of anaerobic work capacity. Recent studies have demonstrated that oral supplementation of creatine monohydrate (CrH2O) increases total muscle creatine stores, and have linked these increases to improved performances in intense intermittent exercise. This study was conducted to determine the effect of CrH2O supplementation on estimates of W' and Wcp derived from the NLin and LinW equations, and to determine the effect of CrH2O on t in exhaustive constant power exercise of different intensities. Fifteen active but untrained university students completed three phases of testing on a cycle ergometer: (1) familiarization, three learning trials, (2) baseline determination of W' and Wcp, four bouts performed at a W selected to elicit fatigue in 90-600 s, and (3) experimental determination of W' and Wcp, four bouts performed at the same W as baseline, but performed after 5 days of ingesting either a placebo (4 x 6 g of glucose/day) or CrH2O (4 x 5 g of CrH2O and 1 g glucose/day). Testing was administered in a double-blind manner. Analyses of covariance revealed a significant effect for CrH2O on both estimates of W' (NLin, P=0.04; LinW, P < 0.01), but not on estimates of Wcp (NLin, P=0.37; LinW; P=0.30). Within groups, t was significantly different for only CrH2O at the two highest Ws (P=0.04). It is concluded that oral ingestion of CrH2O increases estimates of W' due to an improved t at the shorter, more intense exercise bouts.

Canebrake rattlesnake envenomation.

STUDY OBJECTIVE: To document the clinical presentation and course of consecutive cases of envenomation by the canebrake rattlesnake (Crotalus horridus atricaudatus). METHODS: The medical care provided all patients envenomated by canebrake rattlesnakes in two institutions was retrospectively reviewed. Particular attention was paid to coagulation abnormalities, serum enzymes, electrocardiographic findings, and treatment with antivenom. RESULTS: Of the 15 patients, envenomation was judged to be mild in 3, moderate in 6, and severe in 5. In one case envenomation caused death. The clinical course generally predicted the degree of increase in the serum creatinine kinase (CK) level, as well as the amount of antivenom used for treatment. Despite increases in serum CK concentration and frequent increases in the serum CK-MB fraction, we found no evidence of cardiac damage. CONCLUSION: In envenomation by North American pit vipers, rhabdomyolysis appears to be characteristic of envenomation by the canebrake rattlesnake. We speculate that toxins in the canebrake venom cause skeletal muscle rhabdomyolysis. Physicians caring for victims of canebrake bite should regard marked increases in CK concentration as coming from skeletal, not cardiac, muscle. Good general medical support and antivenom for victims with moderate to severe envenomation appears effective.

Three-dimensional moment invariants.

Recognition of three-dimensional objects independent of size, position, and orientation is an important and difficult problem of scene analysis. The use of three-dimensional moment invariants is proposed as a solution. The generalization of the results of two-dimensional moment invariants which had linked two-dimensional moments to binary quantics is done by linking three-dimensional moments to ternary quantics. The existence and number of nth order moments in two and three dimensions is explored. Algebraic invariants of several ternary forms under different orthogonal transformations are derived by using the invariant property of coefficients of ternary forms. The result is a set of three-dimensional moment invariants which are invariant under size, orientation, and position change. This property is highly significant in compressing the data which are needed in three-dimensional object recognition. Empirical examples are also given.

The selection of critical subsets for signal, image, and scene matching.

A basic matching problem consists of locating a reference subset in a larger set of data subject to a given criterion. Variations of the problem include template matching for object recognition, matched filtering for signal detection, image registration, change detection, cartography feature location, correlation guidance, and scene matching. In the general case the data sets may be made by completely different sensors at different geometrical orientations. A data set in N dimensions can be considered as a function in N-space. The critical subset selection problem arises when one is given a function and must select some subset of the function to match with the original. In some cases uniqueness is a key feature of the best subset. Uniqueness may be measured by the number and relative magnitudes of the peaks in the cross correlation function of the original and subset functions. For a unique subset, another desirable characteristic is lack of ambiguity. This characteristic may be measured using the correlation length or 50 percent width of the main correlation peak. The smaller the correlation length, the greater the certainty one has in detecting the correct match position. In this paper a method is presented for selecting the ``best'' subset of a scene where best is defined in terms of the minimum correlation length. The best solution is shown to be a function of the entire scene, i.e., an improper subset.

Performance comparison of scene matching techniques.

The problem of matching two images of the same scene, taken by different sensors under different viewing geometries, is a challenging problem in the field of image processing and pattern recognition. The scenes are usually transformed so drastically by the different viewing geometries and sensor characteristics that it is extremely difficult, if not impossible, to match the original images without the proper data processing. Geometric and intensity transformations must be performed to bring the matching elements and their intensity into a one-to-one correspondence. Objects of interest represented by subimages of one scene were located in the other using scene matching techniques with intensity difference and edge features as measurement features. Performance characteristics of the matches by these techniques are presented in terms of the probability of a match as a function of the probability of false fix.

Hybrid optical-digital radiography-based system for lung disease detection.

A hybrid optical-digital system for automated measurement and disease classification of chest radiographs has been constructed. Initial results from the use of this system for classification of opacity textural patterns associated with a specific diffuse lung disease (coal workers pneumoconiosis) are presented. This system consists of three subsystems which include a digital image scanner for lung field detection, a computercontrolled X - Y transport for film positioning, and a Fraunhofer diffraction pattern sampling unit for opacity detection and measurement. A minicomputer is used to integrate these subsystems as well as render a film quality and disease classification through the use of discriminant functions and probability estimates.