Persistent organic pollutants in green sea turtles (Chelonia mydas) inhabiting two urbanized Southern California habitats

Within Southern California, east Pacific green sea turtles (Chelonia mydas) forage year-round, taking advantage of diverse food resources, including seagrass, marine algae, and invertebrates. Assessing persistent organic pollutants (POP) in green turtle aggregations in the Seal Beach National Wildlife Refuge (SBNWR, n = 17) and San Diego Bay (SDB, n = 25) can help quantify contamination risks for these populations. Blood plasma was analyzed for polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs). PCBs and body size explained much of the separation of turtles by foraging aggregation in a principal component analysis. Turtles from SDB had significantly (p < 0.001) higher total PCBs than SBNWR turtles. Most PCBs detected in turtles were non-dioxin-like PCB congeners (153, 138, 99) that are associated with neurotoxicity. Recaptured turtles' POP levels changed significantly over time indicating significant variation in POP levels through time and space, even among adjacent foraging locations.

Trace metals in green sea turtles (Chelonia mydas) inhabiting two southern California coastal estuaries

Foraging aggregations of east Pacific green sea turtles (Chelonia mydas) inhabit the Seal Beach National Wildlife Refuge (SBNWR) and San Diego Bay (SDB), two habitats in southern California, USA, located near urbanized areas. Both juvenile and adult green turtles forage in these areas and exhibit high site fidelity, which potentially exposes green turtles to anthropogenic contaminants. We assessed 21 trace metals (TM) bioaccumulated in green turtle scute and red blood cell (RBC) samples collected from SBNWR (n = 16 turtles) and SDB (n = 20 turtles) using acid digestion and inductively coupled plasma mass spectrometry. Principal component analyses of TM composition indicate that SBNWR and SDB turtles have location-specific contaminant signatures, characterized by differences in cadmium and selenium concentrations: SBNWR turtles had significantly more cadmium and selenium in RBC and more selenium in scute samples, than SDB turtles. Cadmium and selenium concentrations in RBC had a strong positive relationship, regardless of location. SBNWR turtles had higher selenium in RBCs than previously measured in other green turtle populations globally. Due to different retention times in blood vs. scute, these results suggest that SBNWR turtles have high long- and short-term selenium exposure. Turtles from SBNWR and SDB had higher trace metal concentrations than documented in green turtle populations that inhabit non-urbanized areas, supporting the hypothesis that coastal cities can increase trace metal exposure to local green turtles. Our study finds evidence that green turtle TM concentrations can differ between urbanized habitats and that long-term monitoring of these green turtles may be necessary.

Volumetric measurement of human calf muscle from magnetic resonance imaging

Muscle mass is a determining factor in skeletal muscle function and is affected by inactivity, immobilization, disease, and aging. The aim of this study was to develop an objective and time-efficient method to quantify the volume and cross-sectional area of human calf muscles using three-dimensional magnetic resonance images. We have estimated the errors incurred in muscle volume measurements arising from artifacts known to occur in magnetic resonance imaging (MRI). The largest source of error was due to partial volume effects, which resulted in overestimation of phantom volumes ranging from 145 to 900 cc by 6% to 13%. The magnitude of this effect has been shown to increase with decreasing object size and decreasing spatial resolution. We have presented a straightforward correction for this effect, which has reduced the volume measurement error to less than 4% for all cases. Through the use of computer simulations, the correction algorithm has been shown to be independent of object shape and orientation. To reduce user subjectivity, a semiautomated computer program has been developed to segment MRI data for particular muscle groups. Images from seven human subjects were analyzed by the program, yielding muscle volumes of 154.2 +/- 23.2, 281.2 +/- 35.8, and 432.2 +/- 83.7 for the lateral gastrocnemius, medial gastrocnemius, and soleus, respectively.

Nevus counting as a risk factor for melanoma: comparison of self-count with count by physician

BACKGROUND

The number of total body nevi is a major risk marker for malignant melanoma. No previous study has evaluated the accuracy of whole body large nevus (> or = 5 mm) self-counts.

OBJECTIVE

Our purpose was to evaluate the accuracy of large nevus self-counts by sex, age, educational level, body site, family history of skin cancer, and nevus characteristics.

METHODS

Self-counting of large nevi by 125 patients was compared with physician counting, with attention to nevus characteristics.

RESULTS

Overall, 79% of the self-counts agreed to within +/- 3 nevi of the physician's count. Analysis of variance revealed that the presence of nonpigmented or flat nevi significantly increased the chance of subject undercount, as did male sex.

CONCLUSION

Self-counts of large nevi are comparable to physician's counts and may be useful for melanoma screening.

Differential Diagnosis of Some Conditions of the Canine and Feline Thorax

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Differential Diagnosis of Some Conditions of the Canine and Feline Thorax : (First Installment)

Routine clinical examination of the chest is described. The basic principles of viewing X-ray plates are mentioned. The conditions of the canine and feline thorax dealt with are mostly those which can be confirmed radiologically during life. The major points of differential diagnosis of each condition are dealt with within groups determined by some cardinal clinical sign. For convenience each condition is dealt with only under one groupheading, although it may have additional signs of some of the other groups. The groups and conditions are as follows:Gross DyspnoeaHydrothoraxPyothoraxPneumothoraxDiaphragmatic herniaPneumoniaCoughDistemperTuberculosisSecondary lung tumourFilaroides osleri infestation of the tracheaKennel coughFeline influenzaTiring on exerciseCardiac valvular diseaseCongenital cardiac diseaseDifficulty in swallowingOesophageal foreign bodyFeline oesophageal annular carcinomaOesophageal diverticulumMega-oesophagus (Achalasia)Oesophageal dilatation associated withvascular anomalies of the right aortic arch.

Transthoracic Surgery

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