The mitochondrial genome of the pentastome parasite Raillietiella orientalis Hett, 1915 (Raillietiellida; Raillietiellidae) with notes on its phylogenetic position.

In this study we sequenced and annotated the complete mitochondrial genome of the invasive reptile parasite Raillietiella orientalis using Illumina DNA sequencing. The length of the mitogenome was 15,320 bp and had a GC content of 33.1%. The mitogenome contained 13 protein-coding genes, two ribosomal RNA genes, and 22 tRNA genes, the order of which was diagnostic of Pancrustacean mitogenomes. A phylogenetic tree constructed from the 13 protein-coding genes of R. orientalis and 26 other Pancrustacean mitogenomes supported the placement of R. orientalis as part of the monophyletic subclass Pentastomida within the Maxillopoda and sister to the subclass Branchiura.

Ophidiomycosis is associated with alterations in the acute glycemic and glucocorticoid stress response in a free-living snake species.

Emerging fungal pathogens are a direct threat to vertebrate biodiversity. Elucidating the mechanisms by which mycoses impact host fitness is an important step towards effective prediction and management of disease outcomes in populations. The vertebrate acute stress response is an adaptive mechanism that allows individuals to meet challenges to homeostasis and survival in dynamic environments. Disease may cause stress, and coping with fungal infections may require shifts in resource allocation that alter the ability of hosts to mount an acute response to other external stressors. We examined the glucocorticoid and glycemic response to acute capture stress in a population of free-living pygmy rattlesnakes, Sistrurus miliarius, afflicted with an emerging mycosis (ophidiomycosis) across seasons. In all combinations of disease status and season, acute capture stress resulted in a significant glucocorticoid and glycemic response. While disease was not associated with elevated baseline or stress-induced corticosterone (CORT), disease was associated with an increased glucocorticoid stress response (post-stress minus baseline) across seasons. Both baseline and stress-induced glucose were lower in snakes with ophidiomycosis compared to uninfected snakes. The relationship between glucose and pre- and post-stress CORT depended on infection status, and positive correlations were only observed in uninfected snakes. The variables which explained CORT and glucose levels were different. The pattern of CORT was highly seasonal (winter high - summer low) and negatively related to body condition. Glucose, on the other hand, did not vary seasonally or with body condition and was strongly related to sex (male high - female low). Our results highlight the fact that circulating CORT and glucose are sensitive to different intrinsic and extrinsic predictor variables and support the hypothesis that disease alters the acute physiological stress response. Whether the effects of ophidiomycosis on the acute stress response result in sublethal effects on fitness should be investigated in future studies.

The invasive pentastome Raillietiella orientalis in a banded water snake from the pet trade.

Raillietiella orientalis is established in Florida and rapidly spreading both geographically and in known host species. A banded water snake (Nerodia fasciata), purchased in Michigan at a regional reptile show, expectorated a pentastome whose morphology and DNA sequence indicated that it was R. orientalis. This event indicates that, through the pet trade, R. orientalis has been spread 1,500 km from its previously known distribution limit. Fecal sample analyses indicated that the snake was shedding large numbers of embryonated eggs for at least several months. The diversity of reptile species that are both known hosts of R. orientalis in Florida and are commonly sold in the pet trade indicates that this invasive pentastome may become a widespread health concern for pet owners and veterinarians.

The population genetics of the causative agent of snake fungal disease indicate recent introductions to the USA.

Snake fungal disease (SFD; ophidiomycosis), caused by the pathogen Ophidiomyces ophiodiicola (Oo), has been documented in wild snakes in North America and Eurasia, and is considered an emerging disease in the eastern United States of America. However, a lack of historical disease data has made it challenging to determine whether Oo is a recent arrival to the USA or whether SFD emergence is due to other factors. Here, we examined the genomes of 82 Oo strains to determine the pathogen's history in the eastern USA. Oo strains from the USA formed a clade (Clade II) distinct from European strains (Clade I), and molecular dating indicated that these clades diverged too recently (approximately 2,000 years ago) for transcontinental dispersal of Oo to have occurred via natural snake movements across Beringia. A lack of nonrecombinant intermediates between clonal lineages in Clade II indicates that Oo has actually been introduced multiple times to North America from an unsampled source population, and molecular dating indicates that several of these introductions occurred within the last few hundred years. Molecular dating also indicated that the most common Clade II clonal lineages have expanded recently in the USA, with time of most recent common ancestor mean estimates ranging from 1985 to 2007 CE. The presence of Clade II in captive snakes worldwide demonstrates a potential mechanism of introduction and highlights that additional incursions are likely unless action is taken to reduce the risk of pathogen translocation and spillover into wild snake populations.

Rat Lungworm (Angiostrongylus cantonensis) in the Invasive Cuban Treefrog (Osteopilus septentrionalis) in Central Florida, USA.

Cuban treefrogs, Osteopilus septentrionalis, were grossly examined for parasites and parasite species confirmed by PCR. Angiostrongylus cantonensis larvae were recovered from the hind leg muscle of O. septentrionalis. This is the first report of the zoonotic rat lungworm in the Cuban treefrog and new geographic location (Volusia County) in Florida, US.

Neuroimaging of central diabetes insipidus.

Central diabetes insipidus (CDI) occurs secondary to deficient synthesis or secretion of arginine vasopressin peptide from the hypothalamo-neurohypophyseal system (HNS). It is characterized by polydipsia and polyuria (urine output >30mL/kg/day in adults and >2l/m2/24h in children) of dilute urine (<250mOsm/L). It can result from any pathology affecting one or more components of the HNS including the hypothalamic osmoreceptors, supraoptic or paraventricular nuclei, and median eminence of the hypothalamus, infundibulum, stalk or the posterior pituitary gland. MRI is the imaging modality of choice for evaluation of the hypothalamic-pituitary axis (HPA), and a dedicated pituitary or sella protocol is essential. CT can provide complimentary diagnostic information and is also of value when MRI is contraindicated. The most common causes are benign or malignant neoplasia of the HPA (25%), surgery (20%), and head trauma (16%). No cause is identified in up to 30% of cases, classified as idiopathic CDI. Knowledge of the anatomy and physiology of the HNS is crucial when evaluating a patient with CDI. Establishing the etiology of CDI with MRI in combination with clinical and biochemical assessment facilitates appropriate targeted treatment. This chapter illustrates the wide variety of causes and imaging correlates of CDI on neuroimaging, discusses the optimal imaging protocols, and revises the detailed neuroanatomy required to interpret these studies.

Extensor mechanism tendinopathy in patients with lateral patellar maltracking.

OBJECTIVE: Patellar maltracking is an important subset of patellofemoral pain syndrome. We hypothesize that maltracking patients have an increased incidence of extensor mechanism dysfunction due to repetitive attempts at stabilization of the patella. Our purpose is to delineate imaging features to identify maltracking patients at risk for extensor mechanism tendinopathy. MATERIALS AND METHODS: Retrospective review of knee MRIs performed for anterior knee pain over a year was conducted to identify 218 studies with imaging findings of maltracking. The cases were evaluated for the presence and degree of patellar and quadriceps tendinopathy, tibial tuberosity-trochlear groove distance (TT-TG) and the distribution and grade of patellofemoral chondrosis. Cases were compared to 100 healthy, age-matched control knee MRIs. RESULTS: The mean age of maltracking patients with either patellar or quadriceps tendinosis was 41.2 years versus 48.2 years in the control population (p = 0.037). The TT-TG was significantly higher in maltracking patients with either patellar or quadriceps tendinosis at 16.49 mm versus 14.99 mm (p = 0.006). Maltrackers with isolated lateral patellofemoral chondrosis had a higher mean TT-TG at 17.4 mm versus 15.4 mm (p = 0.007). Extensor mechanism tendinosis was increased in the maltracking population compared to the controls at 57.8% versus 27.3% (p = 0.004). CONCLUSION: Extensor mechanism tendinosis is more common in the maltracking population and occurs at a younger age. TT-TG distance is significantly increased in patients with extensor mechanism dysfunction and in patients with isolated lateral patellofemoral chondrosis. TT-TG measurement can be used independently to identifying maltrackers who may be at risk for future complications.

Lateral femoral condyle insufficiency fractures: imaging findings, demographics, and analysis of outcomes.

OBJECTIVE: To describe imaging characteristics and demographics of lateral femoral condyle insufficiency fractures (LFCIFs) and identify characteristics associated with progression to epiphyseal collapse. MATERIALS AND METHODS: A retrospective review of 105 consecutive patients with LFCIF was performed (mean age 58.1 years) after excluding post-traumatic and pathological fractures. Lesion size and location, presence of bone marrow edema-like signal, soft tissue edema, chondrosis grade, and meniscus pathology were documented. Demographics were recorded from the electronic patient record. Follow-up MRI and/or radiographs were evaluated for healing/stability or progression to epiphyseal collapse. Bone mineral density was assessed from dual-energy x-ray absorptiometry (DEXA) scans and/or radiographs. RESULTS: Fifty-six female and 49 male subjects were included. Female subjects were older at presentation (60.5 versus 56.3 years, p = .02). A total of 61.7% of the subjects with available DEXA and/or radiographs had osteopenia/osteoporosis. The central weight-bearing (61%) and outer condyle (54.3%) were most involved. High-grade chondrosis was present in ≥ 1 compartment in 70.5% including 42% in the lateral compartment. A total of 67.6% had ≥ 1 meniscus tear with similar frequency of medial and lateral tears (47.6% versus 41%). Bone marrow edema-like signal was present in all cases; soft tissue edema was present in 83.8%. Fifty-three subjects had available follow-up MRI (n = 24) and/or radiographs (n = 29). Increased age, fracture dimensions, presence of medial meniscus tears, and high-grade patellofemoral chondrosis were associated with progression (p ≤ .05). CONCLUSION: LFCIFs are associated with meniscus tears, high-grade chondrosis, and osteopenia/osteoporosis with more global knee pathology present when compared with medial femoral condyle insufficiency fracture. Increased age, medial meniscus tears, fracture dimensions, and high-grade patellofemoral chondrosis were associated with progression.

The metabolic response to an immune challenge in a viviparous snake, Sistrurus miliarius.

Mounting an immune response may be energetically costly and require the diversion of resources away from other physiological processes. Yet, both the metabolic cost of immune responses and the factors that impact investment priorities remain poorly described in many vertebrate groups. For example, although viviparity has evolved many times in vertebrates, the relationship between immune function and pregnancy has been disproportionately studied in placental mammals. To examine the energetic costs of immune activation and the modulation of immune function during pregnancy in a non-mammalian vertebrate, we elicited an immune response in pregnant and non-pregnant pygmy rattlesnakes, Sistrurus miliarius, using lipopolysaccharide (LPS). Resting metabolic rate (RMR) was measured using flow-through respirometry. Immune function was examined using bactericidal assays and leukocyte counts. The RMR of pygmy rattlesnakes increased significantly in response to LPS injection. There was no statistically significant difference in the metabolic response of non-reproductive and pregnant snakes to LPS. Mean metabolic increments for pregnant females, non-reproductive females, and males were 13%, 18% and 26%, respectively. The ratio of heterophils to lymphocytes was elevated in response to LPS across reproductive categories; however, LPS did not impact plasma bactericidal ability in non-reproductive snakes. Although pregnant females had significantly higher plasma bactericidal ability compared with non-reproductive snakes prior to manipulation, their bactericidal ability declined in response to LPS. LPS administration also significantly reduced several litter characteristics, particularly when administrated relatively early in pregnancy. Our results indicate that immune performance is energetically costly and is altered during pregnancy, and that immune activation during pregnancy may result in tradeoffs that affect offspring in a viviparous reptile.

Acromioclavicular Joint: What to Look for.

Acromioclavicular joint (ACJ) pathology is a common source of shoulder girdle pain, frequently coexisting with and sharing overlapping clinical features of rotator cuff and glenohumeral articular lesions. ACJ trauma and osteoarthritis dominate clinical presentation; however, an array of pathologies can affect the joint. MR imaging of the ACJ is a powerful secondary diagnostic tool in early diagnosis of ACJ pathology and in accurate assessment of ACJ injuries, helping to resolve clinically challenging cases and allowing for individualized treatment planning. Knowledge of ACJ anatomy, biomechanics, and pathology is fundamental to interpreting and providing a clinically relevant ACJ MR imaging report.

Comparison of outcomes and cost-effectiveness of trisacryl gelatin microspheres alone versus combined trisacryl gelatin microspheres and gelatin sponge embolization in uterine fibroid embolization.

BACKGROUND: Uterine fibroid embolization (UFE) is an effective treatment for uterine leiomyomata. Optimizing the choice of embolic agents is imperative to achieve better patient outcomes with maximum resource utilization. PURPOSE: To evaluate the efficacy and cost-effectiveness of trisacryl gelatin microspheres (TAGM) versus combined TAGM and gelatin sponge (GS) embolization in the treatment of symptomatic uterine leiomyomata. MATERIAL AND METHODS: Between July 2007 and December 2010, 106 consecutive patients underwent UFE with TAGM. Between January 2011 and December 2016, 123 consecutive patients underwent UFE with a combination of TAGM/GS. The primary outcomes were successful infarction rate (≥90% infarction) of the dominant leiomyoma and percentage reduction in uterine and dominant leiomyoma volume on MRI at six months. Secondary outcomes included adverse event rates, pain scores, and change in clinical symptoms at six months. The embolic agents utilized per procedure were recorded and a cost-effectiveness analysis was performed. RESULTS: Baseline characteristics of both groups were similar. Successful infarction was achieved in 93.2% of the TAGM group and 94.6% of the TAGM/GS group (P = 0.52). Reduction in uterine volume (TAGM 40.7%, TAGM/GS 44.4%, P = 0.16) and dominant leiomyoma volume (TAGM 47.6%, TAGM/GS 50.1%, P = 0.29) at six months was similar. No significant difference was observed in symptom improvement at six months (P = 0.8). The mean number of TAGM vials utilized and cost per procedure was 6.3 and $1688.40 for TAGM embolization and 3.6 and $979.50 for TAGM/GS embolization, respectively. CONCLUSION: Primary and secondary outcomes were comparable when performing UFE with TAGM versus combined TAGM/GS. The combined use of TAGM/GS reduced the mean cost of embolic agents by 42%.

High levels of functional divergence in toxicity towards prey among the venoms of individual pigmy rattlesnakes.

Venom is a complex molecular phenotype that shows high levels of variation in expressed proteins between individuals within and between populations. However, the functional significance of this variation in terms of toxicity towards prey is largely unknown. Here, we assessed the relative toxicity of venom from individual pygmy rattlesnakes ( Sistrurus miliarius) on brown anoles ( Anolis sagrei) using a novel assay involving tests of fixed doses of venom from individual snakes on individual lizards. We found high levels of functional variation between individual venoms within populations with individual differences (nested within population) explaining 3.6 times more variation in toxicity than population differences. Our results suggest a previously unappreciated adaptive significance to within-population variation in venom. They argue that selective mechanisms that maintain variation within populations may be of equal or greater importance to divergent selection leading to local adaption between populations as evolutionary explanations of venom variation within species.

Evidence of Vertical Transmission of the Snake Fungal Pathogen Ophidiomyces ophiodiicola.

Snake fungal disease (ophidiomycosis) is an emerging infection of snakes caused by Ophidiomyces ophiodiicola. Little is known about mechanisms of this pathogen's transmission and its implications for conservation of wild snake populations. We report four cases with evidence of vertical transmission of O. ophiodiicola from dam to offspring.

Superior bearing dislocation in a unicompartmental total knee prosthesis.

The mobile bearing Oxford Unicompartmental Knee Prosthesis (OUKP) is the most commonly used treatment of osteoarthritis confined to 1 compartment of the knee. Dislocation of the mobile bearing is an uncommon but recognized complication of the OUKP. Patients typically present with severe pain and reduced range of motion of the affected knee. Radiological evaluation of OUKP can be challenging and requires knowledge of the prosthesis components and common complication patterns. Dislocation of the bearing can easily be overlooked on plain radiographs as the bearing is radiolucent, distinguished only by radiopaque markers. Further imaging in particular with CT may be required to adequately evaluate for prosthesis complications. Advances in prosthesis design and surgical technique may reduce the rate of bearing dislocation.

Therapeutic Intervention in Musculoskeletal Radiology: Current Practice and Future Directions.

Over the last several decades, the volume and range of therapeutic musculoskeletal (MSK) interventions that radiologists can offer their patients has dramatically increased. With new materials and improving imaging modalities, as well as significant investment in research, the field of MSK interventional radiologic intervention will likely continue to expand. In this article, we summarize the range of interventions currently available to the MSK radiologist. We also seek to explore new and emerging techniques that may become commonplace in the near future while considering the challenges that may lie ahead in the field of MSK radiology.

Musculoskeletal Imaging: Current Practice and Future Directions.

Musculoskeletal (MSK) radiology plays a crucial role in the diagnosis and management of MSK disorders and has rapidly expanded in tandem with advances in technology and improved access to imaging. Although anatomical imaging remains the mainstay of MSK radiology, significant progress has been made in functional and molecular imaging as well as in hybrid imaging with an expanding armament of technologies becoming available or in development. A vast array of research is occurring in MSK imaging, and this review article highlights some of the most promising current and future clinical applications in development in each of the major imaging modalities. Identifying the clinical utility of these technologies in an era of rising health care costs is an important challenge for MSK radiologists.

Seasonal testosterone and corticosterone patterns in relation to body condition and reproduction in a subtropical pitviper, Sistrurus miliarius.

Seasonal constraints on the timing and intensity of reproductive events shape observed variation in life history strategies across latitudes. Selection acts on the endocrine mechanisms that underlie reproductive investment. It is therefore important to examine the seasonal relationship between hormones and reproduction in geographically and phylogenetically diverse taxa. Snakes have proven to be a valuable model in investigations of seasonal hormone production and behavior in field-active vertebrates, but most research has focused on temperate populations from highly seasonal environments. To reduce this bias, we provide a description of the seasonal relationships among testosterone, corticosterone, body condition, and reproductive behavior in a subtropical population of Pygmy Rattlesnakes, Sistrurus miliarius. In central Florida, Sistrurus miliarius exhibits a prolonged breeding season (September-January) compared to most temperate zone snakes. Despite the extended breeding season, the pattern of testosterone in the population was highly seasonal and very similar to temperate pitvipers with a shorter mating season. Testosterone declined steadily through the mating season, but males sampled while engaging in mating behaviors had higher testosterone compared to solitary males throughout the mating season. Testosterone was negatively related to corticosterone throughout the breeding season and during times of year when the gonads were presumed to be quiescent and no mating behavior was observed. Testosterone was positively related to individual body condition both within and outside of the breeding season. A review of the literature reveals no consistent pattern regarding the relationship between corticosterone and testosterone in snakes, but suggests that the condition-dependence of steroid production may be consistent across snake taxa.

The importance of species: Pygmy rattlesnake venom toxicity differs between native prey and related non-native species.

Venom toxicity assessments are often based upon non-native surrogate prey species that are not consumed in the wild by the venomous predator. This raises questions about the relevance of toxicity results on these "model" prey in addressing ecological or evolutionary questions about venom effects on native prey. We explore this issue by comparing the toxicity of venom from pygmy rattlesnakes (Sistrurus miliarius) on taxonomically-diverse sets of model (non-native) and native prey. Specifically, we compared rattlesnake venom toxicity for nine species from three broad taxonomic groups of prey (reptiles, mammals, and amphibians) to determine whether estimates of venom toxicity for the non-native model species of each group was representative of species which were native prey. In all three groups, model species (Anolis sagrei, Mus musculus, and Lithobates pipiens) had a significantly different mortality response from one or more of the native prey species (Anolis carolinensis, Peromyscus gossypinus, Lithobates sphenocephalus, Hyla cinerea, and Hyla squirella) that the models were meant to represent. Two features of our results suggest an importance of evolutionary history in understanding these differences. First, there was a phylogenetic component to prey responses to venom in that in each group, non-native models and congeneric native prey showed more similar responses than prey from other genera suggesting that venom may act on common prey targets that result from common ancestry. Second, native prey generally showed higher LD50 values than their non-native counterparts, suggesting greater resistance to venom from a predator with which they interact in nature. Our results suggest that researchers should use native prey to generate measures of venom toxicity that are ecologically and evolutionarily relevant. If this is not possible using "model" prey species that are close taxonomic relatives to natural prey may be a reasonable alternative.

Tracking Outcomes of Snake Fungal Disease in Free-ranging Pygmy Rattlesnakes ( Sistrurus miliarius).

Snake fungal disease (SFD) is caused by the fungus Ophidiomyces ophiodiicola and its documentation in wild snake populations has risen sharply in the past decade. Little is known regarding the fate of individual, free-ranging snakes afflicted with SFD. We monitored an afflicted population of pygmy rattlesnakes ( Sistrurus miliarius) at Lake Woodruff National Wildlife Refuge in Central Florida, US for 2 yr. The severity of SFD in individual snakes was unrelated to the probability of their recapture later in the study, and half of the snakes diagnosed as severely infected at the onset of the study were recaptured later with no clinical signs of SFD. The clinical progress of 12 serially recaptured individuals also showed that individuals cleared the infection and fluctuated between no or low and severe clinical signs over the 2-yr study.