Massive branchial henneguyosis of catfish: A distinct, myxozoan-induced gill disease caused by severe interlamellar Henneguya exilis infection in catfish aquaculture.

Proliferative gill disease (PGD), caused by the myxozoan Henneguya ictaluri, has been the most notorious parasitic gill disease in the US catfish aquaculture industry. In 2019, an unusual gill disease caused by massive burdens of another myxozoan, Henneguya exilis, was described in channel (Ictalurus punctatus) × blue (Ictalurus furcatus) hybrid catfish. Targeted metagenomic sequencing and in situ hybridization (ISH) were used to differentiate these conditions by comparing myxozoan communities involved in lesion development and disease pathogenesis between massive H. exilis infections and PGD cases. Thirty ethanol-fixed gill holobranchs from 7 cases of massive H. exilis infection in hybrid catfish were subjected to targeted amplicon sequencing of the 18S rRNA gene and compared to a targeted metagenomic data set previously generated from clinical PGD case submissions. Furthermore, serial sections of 14 formalin-fixed gill holobranchs (2 per case) were analyzed by RNAscope duplex chromogenic ISH assays targeting 8 different myxozoan species. Targeted metagenomic and ISH data were concordant, indicating myxozoan community compositions significantly differ between PGD and massive branchial henneguyosis. Although PGD cases often consist of mixed species infections, massive branchial henneguyosis consisted of nearly pure H. exilis infections. Still, H. ictaluri was identified by ISH in association with infrequent PGD lesions, suggesting coinfections occur, and some cases of massive branchial henneguyosis may contain concurrent PGD lesions contributing to morbidity. These findings establish a case definition for a putative emerging, myxozoan-induced gill disease of farm-raised catfish with a proposed condition name of massive branchial henneguyosis of catfish (MBHC).

Retinal injury from a laser skin resurfacing device during medical tourism: a public health concern.

BACKGROUND: Laser skin resurfacing is a popular cosmetic procedure for noninvasive skin rejuvenation. Since health insurance plans often do not cover these types of procedures, patients often pay out of pocket. Consequently, there is an incentive to go abroad, where prices are more affordable. However, practitioners in destination countries may lack rigorous training on laser safety, regulatory oversight, or licensing, especially on devices used for "cosmetic" procedures. In certain cases, this can lead to tragic outcomes, especially when underqualified practitioners operate medical-grade laser devices. CASE PRESENTATION: A 29-year-old woman suffered a retinal burn from a handheld Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser pulse device used to perform skin resurfacing treatment at a medical spa in Vietnam. The patient was not adequately informed about the potential risk to her vision and was not provided with any eye protection. A momentary, unintended laser exposure to the patient's right eye led to irreversible vision loss due to a macular burn. This incident caused immediate pain, followed by the sudden appearance of floaters, along with a retinal and vitreous hemorrhage. Despite treatment with off-label bevacizumab for the development of a choroidal neovascular membrane, vision remained at the level of counting fingers because of the presence of the macular scar. CONCLUSION: When utilizing laser-based devices, it is crucial to employ safety measures, such as the wearing of safety goggles or the use of eye shields to protect ocular tissues from potential damage. The growing availability of cosmetic laser devices presents a substantial public health risk, because numerous operators lack adequate training in essential safety standards, or they neglect to follow them. Furthermore, patients seeking services abroad are subject to the regulatory practices of the destination country, which may not always enforce the requisite safety standards. Further research is needed to determine regional and global incidence of laser-related injuries to help direct educational and regulatory efforts.

Case Report: Vision-Threatening Fungal Keratitis in a Service Member Stationed at Guantanamo Bay.

Fungal keratitis is a major cause of corneal blindness worldwide. Compared to other types of infectious keratitis, fungal keratitis has a relatively poor prognosis because of various factors such as delayed patient presentation and diagnosis. Although associated in earlier studies with poverty and low socioeconomic status, military personnel stationed in tropical and subtropical climates, in low-resource settings, are at risk. Here, we report a case of a 20-year-old active duty contact lens-wearing military service member stationed at Guantanamo Bay who developed a severe vision-threatening fungal keratitis in her left eye. Enhancing health and safety precautions in at-risk settings, maintaining vigilance, and leveraging new imaging modalities will be important to ensure early recognition and treatment.

Flavobacterium covae is the predominant species of columnaris-causing bacteria impacting the Channel Catfish industry in the southeastern United States.

OBJECTIVE: Columnaris disease is a leading cause of disease-related losses in the catfish industry of the southeastern United States. The term "columnaris-causing bacteria" (CCB) has been coined in reference to the four described species that cause columnaris disease: Flavobacterium columnare, F. covae, F. davisii, and F. oreochromis. Historically, F. columnare, F. covae, and F. davisii have been isolated from columnaris disease cases in the catfish industry; however, there is a lack of knowledge of which CCB species are most prevalent in farm-raised catfish. The current research objectives were to (1) sample columnaris disease cases from the U.S. catfish industry and identify the species of CCB involved and (2) determine the virulence of the four CCB species in Channel Catfish Ictalurus punctatus in controlled laboratory challenges. METHODS: Bacterial isolates or swabs of external lesions from catfish were collected from 259 columnaris disease cases in Mississippi and Alabama during 2015-2019. The DNA extracted from the samples was analyzed using a CCB-specific multiplex polymerase chain reaction to identify the CCB present in each diagnostic case. Channel Catfish were challenged by immersion with isolates belonging to each CCB species to determine virulence at ~28°C and 20°C. RESULT: Flavobacterium covae was identified as the predominant CCB species impacting the U.S. catfish industry, as it was present in 94.2% (n = 244) of diagnostic case submissions. Challenge experiments demonstrated that F. covae and F. oreochromis were highly virulent to Channel Catfish, with most isolates resulting in near 100% mortality. In contrast, F. columnare and F. davisii were less virulent, with most isolates resulting in less than 40% mortality. CONCLUSION: Collectively, these results demonstrate that F. covae is the predominant CCB in the U.S. catfish industry, and research aimed at developing new control and prevention strategies should target this bacterial species. The methods described herein can be used to continue monitoring the prevalence of CCB in the catfish industry and can be easily applied to other industries to identify which Flavobacterium species have the greatest impact.

Species-specific in situ hybridization confirms arrested development of Henneguya ictaluri in hybrid catfish (Channel Catfish × Blue Catfish) under experimental conditions, with notes on mixed-species infections in clinical cases of proliferative gill disease from Mississippi catfish aquaculture.

OBJECTIVE: Proliferative gill disease (PGD) in Channel Catfish Ictalurus punctatus and hybrid catfish (Channel Catfish × Blue Catfish I. furcatus) is attributed to the myxozoan Henneguya ictaluri. Despite evidence of decreased H. ictaluri transmission and impaired parasite development in hybrid catfish, PGD still occurs in hybrid production systems. Previous metagenomic assessments of clinical PGD cases revealed numerous myxozoans within affected gill tissues in addition to H. ictaluri. The objective of this study was to investigate the development and pathologic contributions of H. ictaluri and other myxozoans in naturally and experimentally induced PGD. METHODS: Henneguya species-specific in situ hybridization (ISH) assays were developed using RNAscope technology. Natural infections were sourced from diagnostic case submissions in 2019. Experimental challenges involved Channel Catfish and hybrid catfish exposed to pond water from an active PGD outbreak, and the fish were sampled at 1, 7, 10, 12, 14, 16, 18, and 20 weeks postchallenge. RESULT: Nine unique ISH probes were designed, targeting a diagnostic variable region of the 18S ribosomal RNA gene of select myxozoan taxa identified in clinical PGD cases. Partial validation from pure H. ictaluri, H. adiposa, H. postexilis, and H. exilis infections illustrated species-specific labeling and no cross-reactivity between different myxozoan species or the catfish hosts. After experimental challenge, mature plasmodia of H. ictaluri and H. postexilis formed in Channel Catfish but were not observed in hybrids, suggesting impaired or delayed sporogenesis in the hybridized host. These investigations also confirmed the presence of mixed infections in clinical PGD cases. CONCLUSION: Although H. ictaluri appears to be the primary cause of PGD, presporogonic stages of other myxozoans were also present, which may contribute to disease pathology and exacerbate respiratory compromise by further altering normal gill morphology. This work provides molecular confirmation and more resolute developmental timelines of H. ictaluri and H. postexilis in Channel Catfish and supports previous research indicating impaired or precluded H. ictaluri sporogony in hybrid catfish.

Characterization of SARS-CoV-2 Aerosols Dispersed During Noninvasive Respiratory Support of Patients With COVID-19.

BACKGROUND: In the midst of the COVID-19 pandemic, noninvasive respiratory support (NRS) therapies such as high-flow nasal cannula (HFNC) and noninvasive ventilation (NIV) were central to respiratory care. The extent to which these treatments increase the generation and dispersion of infectious respiratory aerosols is not fully understood. The objective of this study was to characterize SARS-CoV-2 aerosol dispersion from subjects with COVID-19 undergoing NRS therapy. METHODS: Several different aerosol sampling devices were used to collect air samples in the vicinity of 31 subjects with COVID-19, most of whom were receiving NRS therapy, primarily HFNC. Aerosols were collected onto filters and analyzed for the presence of SARS-CoV-2 RNA. Additional measurements were collected in an aerosol chamber with healthy adult subjects using respiratory therapy devices under controlled and reproducible conditions. RESULTS: Fifty aerosol samples were collected from subjects receiving HFNC or NIV therapy, whereas 6 samples were collected from subjects not receiving NRS. Only 4 of the 56 aerosol samples were positive for SARS-CoV-2 RNA, and all positive samples were collected using a high air flow scavenger mask collection device placed in close proximity to the subject. The chamber measurements with healthy subjects did not show any significant increase in aerosol dispersion caused by the respiratory therapy devices compared to baseline. CONCLUSIONS: Our findings demonstrate very limited detection of SARS-CoV-2-containing aerosols in the vicinity of subjects with COVID-19 receiving NRS therapies in the clinical setting. These results, combined with controlled chamber measurements showing that HFNC and NIV device usage was not associated with increased aerosol dispersion, suggest that NRS therapies do not result in increased dispersal of aerosols in the clinical setting.

EXPERIMENTAL ELUCIDATION OF THE LIFE CYCLE OF DREPANOCEPHALUS SPATHANS (DIGENEA: ECHINOSTOMATIDAE) WITH NOTES ON THE MORPHOLOGICAL PLASTICITY OF D. SPATHANS IN THE UNITED STATES.

The echinostomatid Drepanocephalus spathans (syn. Drepanocephalus auritus) parasitizes the double-crested cormorant Phalacrocorax auritus. In North America, the marsh rams-horn snail Planorbella trivolvis and ghost rams-horn snail Biomphalaria havanensis serve as snail intermediate hosts, both of which inhabit catfish aquaculture ponds in the southeastern United States. Studies have demonstrated D. spathans exposure can be lethal to juvenile channel catfish Ictalurus punctatus. Two studies were undertaken to elucidate the life cycle of D. spathans to establish a developmental time line. In both studies, D. spathans cercariae collected from naturally infected P. trivolvis individuals were used to infect channel catfish fingerlings, which were then fed to double-crested cormorants (DCCOs) that had been pharmaceutically dewormed. In study 1, laboratory-reared P. trivolvis and B. havanensis individuals were placed in aviary ponds with experimentally infected DCCO and examined bi-weekly for release of cercariae. Trematode eggs were observed in the feces of exposed birds 3 days post-infection. Birds were sacrificed 18 days post-exposure (dpe), and gravid adults morphologically and molecularly consistent with D. spathans were recovered. Snails from the aviary pond were observed shedding D. spathans cercariae 18-54 dpe. In study 2, trematode eggs were observed in the feces of exposed DCCOs beginning 8 dpe. Once eggs were observed, birds were allowed to defecate into clean tanks containing naïve laboratory-reared P. trivolvis individuals. Additionally, eggs from experimental DCCO feces were recovered by sedimentation and placed in an aquarium housing laboratory-reared P. trivolvis individuals. Birds in study 2 were sacrificed after 60 days, and gravid D. spathans specimens were recovered. Snails from the experimental DCCO tanks shed D. spathans cercariae 89-97 dpe. Lastly, trematode eggs were isolated and observed for the hatching of miracidia, which emerged on average after 16 days at ambient temperatures. No D. spathans adults were observed in control birds fed non-parasitized fish. This is the first experimental confirmation of the D. spathans life cycle, resolving previously unknown developmental time lines. In addition, the effects of fixation on adult trematode morphology were assessed, clarifying reports of pronounced morphological plasticity for D. spathans.

MYXOZOAN COMMUNITY COMPOSITION AND DIVERSITY IN CLINICAL CASES OF PROLIFERATIVE GILL DISEASE IN MISSISSIPPI CATFISH AQUACULTURE.

An abundance of morphologically variable Henneguya species complicates the understanding of disease relationships between ictalurid catfish and myxozoan (Phylum: Cnidaria) parasites on North American aquaculture operations. Henneguya ictaluri, the cause of proliferative gill disease (PGD) in channel and hybrid catfish, is arguably the most important parasite of commercial catfish aquaculture in the southeastern United States. While research indicates arrested development and limited sporogenesis of H. ictaluri in channel (Ictalurus punctatus) × blue (Ictalurus furcatus) hybrid catfish, incidents of PGD persist in hybrid production systems. This work investigated the influence of fish host on myxozoan community composition and diversity within naturally infected gill tissues from diagnostic case submissions to the Aquatic Research and Diagnostic Laboratory in Stoneville, Mississippi, from 2017 to 2019. Gills collected from farm-raised catfish with clinical PGD were subjected to metagenomic amplicon sequencing of the myxozoan 18S SSU rDNA gene diagnostic variable region 3 (DVR3). Myxozoan community composition significantly differed between channel and hybrid catfish PGD cases, with channel catfish having more diverse community structures. Channel catfish gills had a greater relative abundance of H. ictaluri in 2017 and 2019, while no differences were observed in 2018. Importantly, H. ictaluri was present in all channel and hybrid catfish PGD cases across all years; however, H. ictaluri was not the most abundant myxozoan in almost half the cases examined, suggesting other myxozoan species may also contribute to PGD pathology. The detection of numerous known and unclassified myxozoan sequences in addition to H. ictaluri provides evidence PGD may involve mixed species infections. Furthermore, the presence of numerous unclassified myxozoan sequences in gill samples from clinical PGD cases indicates the number of described species from U.S. farm-raised catfish vastly underestimates the true myxozoan diversity present within the varied pond microcosms associated with catfish aquaculture.

New data on Henneguya postexilis Minchew, 1977, a parasite of channel catfish Ictalurus punctatus, with notes on resolution of molecular markers for myxozoan phylogeny.

Previous morphological and histological data are supplemented with molecular and ultrastructural data for a Henneguya sp. isolated from farm-raised channel catfish Ictalurus punctatus in Mississippi, USA. Myxospores were cryptic, encapsulated within a thin layer of epithelium in the gill lamellae with spore measurements consistent with the original description of Henneguya postexilis Minchew, 1977. Myxospores were 42.7-49.1 µm in total length with spore bodies 12.1-17.2 × 3.6-4.8 × 2.9-3 µm. Polar capsules were of unequal length, with the longer capsule being 4.4-6.7 × 1.1-1.6 µm and the shorter capsule being 4.4-6.4 × 1.1-1.6 µm. Polar tubules had 6-8 turns. Caudal processes were 25.7-38.1 µm in length. Spores were encapsulated in a thin layer of epithelium in the gill lamellae. Molecular data from the most commonly used markers for myxozoan identification and phylogeny, partial 18S small subunit ribosomal gene (SSU), partial 28S large subunit ribosomal gene (LSU), and elongation factor 2 (EF2) were generated for H. postexilis. Additionally, novel data for LSU and EF2 were generated for archived myxozoan specimens from farm-raised catfish (H. mississippiensis, H. ictaluri, H. exilis, H. adiposa, H. sutherlandi, H. bulbosus, Unicauda fimbrethilae), as well as archived specimens from wild fish (H. laseeae [from Pylodictis olivaris], Hennegoides flockae [from Aphredoderus sayanus], Myxobolus cloutmani [from Cycleptus elongatus]. These include the first EF2 sequence data for the genera Hennegoides and Unicauda. Phylogenetic analyses using these data placed H. postexilis in well supported clades with other ictalurid-infecting Henneguya species. Phylogenetic signal assessments on these analyses suggest that while SSU provided the greatest phylogenetic signal, LSU yielded comparable signal, supporting previous work implying this region may be underutilised in reconstructing myxobolid phylogenies.

End-stage crystalline maculopathy with retinal atrophy in Sjögren-Larsson syndrome: a case report and review of the literature.

Sjögren-Larsson syndrome (SLS) is a rare, autosomal recessive neurocutaneous disorder. It is caused by the inheritance of sequence variants in the ALDH3A2 gene, which codes for fatty aldehyde dehydrogenase (FALDH). Universal signs of the condition are congenital ichthyosis, spastic paresis of the lower and upper limbs, and reduced intellectual ability. In addition to this clinical triad, patients with SLS experience dry eyes and decreased visual acuity caused by a progressive retinal degeneration. Examination of the retina in patients with SLS often reveals glistening yellow crystal-like deposits surrounding the fovea. This crystalline retinopathy often develops in childhood and is considered pathognomonic for the disease. The metabolic disorder typically shortens lifespan to half that of the unaffected population. However, now that patients with SLS live longer, it becomes increasingly important to understand the natural course of the disease. Our case describes a 58-year-old woman with advanced SLS whose ophthalmic examination illustrates the end-stage of the retinal degeneration. Optical coherence tomography (OCT) and fluorescein angiography confirm the disease is restricted to the neural retina with dramatic thinning of the macula. This case is unique since it is among the most advanced both in terms of chronological age and severity of retinal disease. While the accumulation of fatty aldehydes, alcohols, and other precursor molecules is the probable cause of retinal toxicity, a more complete understanding of the course of retinal degeneration may aid in the development of future treatments. The aim of our presentation of this case is to increase awareness of the disease and to foster interest in therapeutic research which may benefit patients with this rare condition.

Eye issues in Sjogren-Larsson Syndrome Sjögren-Larsson syndrome (SLS) is a rare, inherited condition that affects the skin and nervous system. It is caused by variations in a gene that controls the way fats are broken down in the body. The three key signs of the disease are (1) peeling, dry skin; (2) muscle stiffness and impaired movement of the arms and legs; and (3) reduced intellectual ability. Most signs of the condition appear shortly after birth. Genetic testing and counseling services can help patients and their families to understand what to expect with SLS. Caring for people with SLS requires teamwork by specialists like neurologists and physical therapists. Because eye problems are common, the early consultation of an eye doctor is also important. An eye examination can also confirm the diagnosis of SLS. SLS often causes the eyes to appear red, feel dry, or become irritated. This can make it hard to see in bright light. Decreased vision at night is also common. This is caused by the progressive loss of the central part of the retina which is needed to see fine details. Because SLS shortens lifespan, it is rare for anyone to reach the final stages of the disease. As patients with SLS are living longer, as illustrated by the individual in our case study, it becomes important to understand how the disease progresses. Unfortunately, treatments to restore vision are not yet available. Nevertheless, some protective measures can be taken. Eye examinations in early childhood are important for preventing damage to the eyes. Wearing glasses can improve vision, as well as protect eyes from accidental injury or falls. Eye drops can provide relief from dry eyes, and sunglasses can reduce glare and sensitivity to light. In the future, gene therapy may be used to treat SLS.

A Review of Bacterial Co-Infections in Farmed Catfish: Components, Diagnostics, and Treatment Directions.

Catfish production is a major aquaculture industry in the United States and is the largest sector of food fish production. As producers aim to optimize production yields, diseases caused by bacterial pathogens are responsible for high pond mortality rates and economic losses. The major bacterial pathogens responsible are Edwardsiella ictaluri, Aeromonas spp., and Flavobacterium columnare. Given the outdoor pond culture environments and ubiquitous nature of these aquatic pathogens, there have been many reports of co-infective bacterial infections within this aquaculture sector. Co-infections may be responsible for altering disease infection mechanics, increasing mortality rates, and creating difficulties for disease management plans. Furthermore, proper diagnoses of primary and secondary pathogens are essential in ensuring the correct treatment approaches for antimicrobials and chemical applications. A thorough understanding of the interactions and infectivity dynamics for these warm water bacterial pathogens will allow for the adoption of new prevention and control methods, particularly in vaccine development. This review aims to provide an overview of co-infective pathogens in catfish culture and present diagnostic case data from Mississippi and Alabama to define prevalence for these multiple-species infections better.

Robotic Assisted Upper Limb Training Post Stroke: A Randomized Control Trial Using Combinatory Approach Toward Reducing Workforce Demands.

Post stroke upper limb rehabilitation is a challenging problem with poor outcomes as 40% of survivors have functionally useless upper limbs. Robot-aided therapy (RAT) is a potential method to alleviate the effort of intensive, task-specific, repetitive upper limb exercises for both patients and therapists. The present study aims to investigate how a time matched combinatory training scheme that incorporates conventional and RAT, using H-Man, compares with conventional training toward reducing workforce demands. In a randomized control trial (NCT02188628, www.clinicaltrials.gov), 44 subacute to chronic stroke survivors with first-ever clinical stroke and predominant arm motor function deficits were recruited and randomized into two groups of 22 subjects: Robotic Therapy (RT) and Conventional Therapy (CT). Both groups received 18 sessions of 90 min; three sessions per week over 6 weeks. In each session, participants of the CT group received 90 min of 1:1 therapist-supervised conventional therapy while participants of the RT group underwent combinatory training which consisted of 60 min of minimally-supervised H-Man therapy followed by 30 min of conventional therapy. The clinical outcomes [Fugl-Meyer (FMA), Action Research Arm Test and, Grip Strength] and the quantitative measures (smoothness, time efficiency, and task error, derived from two robotic assessment tasks) were independently evaluated prior to therapy intervention (week 0), at mid-training (week 3), at the end of training (week 6), and post therapy (week 12 and 24). Significant differences within group were observed at the end of training for all clinical scales compared with baseline [mean and standard deviation of FMA score changes between baseline and week 6; RT: Δ4.41 (3.46) and CT: Δ3.0 (4.0); p < 0.01]. FMA gains were retained 18 weeks post-training [week 24; RT: Δ5.38 (4.67) and week 24 CT: Δ4.50 (5.35); p < 0.01]. The RT group clinical scores improved similarly when compared to CT group with no significant inter-group at all time points although the conventional therapy time was reduced to one third in RT group. There were no training-related adverse side effects. In conclusion, time matched combinatory training incorporating H-Man RAT produced similar outcomes compared to conventional therapy alone. Hence, this study supports a combinatory approach to improve motor function in post-stroke arm paresis. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02188628.

Pathologic Changes Associated With Respiratory Compromise And Morbidity Due To Massive Interlamellar Henneguya Exilis Infection In Channel × Blue Hybrid Catfish.

There are multiple Henneguya spp. (Myxozoa: Myxobolidae) endemic to North American catfish aquaculture that affect the gills of channel catfish and their hybrids. These parasites are morphologically similar, and confusion exists regarding the predilection sites and pathologic changes associated with different species. In the spring of 2018, channel (Ictalurus punctatus) female × blue (Ictalurus furcatus) male hybrid catfish from 2 separate commercial operations in northwest Mississippi were submitted for diagnostic assessment in response to observed morbidity and reduced feeding activity. Fish presented with unusually heavy infections of Henneguya spp. plasmodia in the gills. The majority of gill filaments contained widespread, pinpoint, raised, white nodules corresponding microscopically to myxospore-filled plasmodia that obliterated interlamellar spaces. The bipolar myxospores were consistent with Henneguya spp. described from North American ictalurids, possessing slender fusiform spore bodies and elongate bifurcate caudal processes. Associated microscopic lesions included lamellar fusion, epithelial hyperplasia, infrequent, localized, granulomatous branchitis, and rare cartilage lysis, suggesting impaired gill function. Mature plasmodia were excised by laser capture microdissection from ethanol-fixed, hematoxylin and eosin-stained histologic sections for molecular analysis. Fragments (700 bp) of a highly variable region of the 18S rRNA gene, diagnostic for the Myxobolidae, were 100% similar at the nucleotide level to Henneguya exilis. Although mortality was negligible, fish in the affected ponds exhibited signs of respiratory distress similar to proliferative gill disease (PGD) caused by Henneguya ictaluri in channel and hybrid catfish. However, gross and microscopic lesions differed markedly from PGD, known colloquially as "hamburger gill disease." While H. exilis has been reported from channel catfish, it is not typically associated with morbidity and mortality and has not previously been reported from channel × blue catfish hybrids. This work characterizes lesions and confirms the etiology of gill disease induced by the myxozoan H. exilis. In addition to PGD and other non-parasitic conditions, massive interlamellar H. exilis infection should be a differential consideration in pond-raised channel and hybrid catfish experiencing signs of respiratory distress.

Arrested Development of Henneguya ictaluri (Cnidaria: Myxobolidae) in ♀ Channel Catfish × â™‚ Blue Catfish Hybrids.

Henneguya ictaluri is the etiologic agent of proliferative gill disease (PGD) in farm-raised Channel Catfish Ictalurus punctatus and hybrid catfish in the southeastern United States, and significant annual losses are attributed to this disease. Research suggests that H. ictaluri infection dynamics in Blue Catfish I. furcatus and hybrid catfish (Channel Catfish × Blue Catfish) differ from those in Channel Catfish. Two separate infectivity trials were conducted to investigate H. ictaluri development in Channel Catfish, Blue Catfish, and their hybrids. On two separate occasions with two different year-classes, fish were exposed to pond water containing H. ictaluri actinospores and sampled weekly for 12 weeks (trial 1) or 14 weeks (trial 2). In trial 1, the presence of H. ictaluri was evaluated histologically and by quantitative PCR of fish tissues, including gills, blood, anterior kidney, brain, heart, liver, posterior kidney, spleen, and stomach. Henneguya ictaluri DNA was detected in significantly higher concentrations throughout multiple organ systems in the Channel Catfish compared to the hybrid catfish and Blue Catfish, with the gills having higher quantities. Myxospores were observed in Channel Catfish gill tissue at 8 weeks postexposure. No myxospores were observed in Blue Catfish or hybrid catfish. The second trial focused on gills only and yielded similar results, with Channel Catfish having significantly greater H. ictaluri DNA quantities than hybrids or Blue Catfish across all time points. Myxospores were observed in Channel Catfish beginning at 6 weeks postexposure and were found in 36% (58/162) of Channel Catfish sampled for molecular and histological analysis during weeks 6-14. Myxospores in hybrid catfish were sparse, with single pseudocysts observed in two hybrid catfish (1.2%) at 14 weeks postexposure. These results imply arrested development of H. ictaluri in hybrid catfish. As such, culture of hybrid catfish may be an effective management strategy to minimize the burden of PGD.

Dietary supplementation with ferric tyrosine improves zootechnical performance and reduces caecal Campylobacter spp. load in broilers.

1. The objective of this study was to evaluate the effect of ferric tyrosine on the reduction of Campylobacter spp. and zootechnical performance in broilers exposed to Campylobacter spp. using a natural challenge model to simulate commercial conditions. Additionally, the minimum inhibitory concentrations (MICs) of ferric tyrosine against common enteropathogens were evaluated. 2. At the start of the trial, 840 healthy male 1-d-old birds (Ross 308) were randomly allocated to 6 replicate pens of 35 birds each and fed diets containing different concentrations of ferric tyrosine (0, 0.02, 0.05 and 0.2 g/kg) in mash form for 42 d. 3. Broilers fed diets containing ferric tyrosine showed significantly higher body weight at d 42 and weight gain compared to the control group. However, birds fed ferric tyrosine ate significantly more than the control birds so significant improvements in feed conversion rate were not observed. 4. Microbiological analyses of caecal samples collected on d 42 of the study showed, per gram of sample, 2-3 log10 reduction in Campylobacter spp. and 1 log10 reduction in Escherichia coli in the groups fed diets containing ferric tyrosine compared to the control. 5. The MICs of ferric tyrosine was >400 mg/l for C. jejuni and >200 mg/l for E. coli and Salmonella enterica, indicating that ferric tyrosine did not exert antimicrobial activity. 6. The results showed that birds fed ferric tyrosine grew faster and consumed more feed compared to the control group, indicating potential benefits of faster time to reach slaughter weight with no significant reduction on feed efficiency. Moreover, ferric tyrosine significantly reduced caecal Campylobacter spp. and E. coli indicating potential as a non-antibiotic feed additive to lower the risk of infections transmitted through the food chain.

Proprioceptive assessment in clinical settings: Evaluation of joint position sense in upper limb post-stroke using a robotic manipulator.

Proprioception is a critical component for motor functions and directly affects motor learning after neurological injuries. Conventional methods for its assessment are generally ordinal in nature and hence lack sensitivity. Robotic devices designed to promote sensorimotor learning can potentially provide quantitative precise, accurate, and reliable assessments of sensory impairments. In this paper, we investigate the clinical applicability and validity of using a planar 2 degrees of freedom robot to quantitatively assess proprioceptive deficits in post-stroke participants. Nine stroke survivors and nine healthy subjects participated in the study. Participants' hand was passively moved to the target position guided by the H-Man robot (Criterion movement) and were asked to indicate during a second passive movement towards the same target (Matching movement) when they felt that they matched the target position. The assessment was carried out on a planar surface for movements in the forward and oblique directions in the contralateral and ipsilateral sides of the tested arm. The matching performance was evaluated in terms of error magnitude (absolute and signed) and its variability. Stroke patients showed higher variability in the estimation of the target position compared to the healthy participants. Further, an effect of target was found, with lower absolute errors in the contralateral side. Pairwise comparison between individual stroke participant and control participants showed significant proprioceptive deficits in two patients. The proposed assessment of passive joint position sense was inherently simple and all participants, regardless of motor impairment level, could complete it in less than 10 minutes. Therefore, the method can potentially be carried out to detect changes in proprioceptive deficits in clinical settings.

Comparative Phenotypic and Genotypic Analysis of Edwardsiella Isolates from Different Hosts and Geographic Origins, with Emphasis on Isolates Formerly Classified as E. tarda, and Evaluation of Diagnostic Methods.

Edwardsiella spp. are responsible for significant losses in important wild and cultured fish species worldwide. Recent phylogenomic investigations have determined that bacteria historically classified as Edwardsiella tarda actually represent three genetically distinct yet phenotypically ambiguous taxa with various degrees of pathogenicity in different hosts. Previous recognition of these taxa was hampered by the lack of a distinguishing phenotypic character. Commercial test panel configurations are relatively constant over time, and as new species are defined, appropriate discriminatory tests may not be present in current test panel arrangements. While phenobiochemical tests fail to discriminate between these taxa, data presented here revealed discriminatory peaks for each Edwardsiella species using matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) methodology, suggesting that MALDI-TOF can offer rapid, reliable identification in line with current systematic classifications. Furthermore, a multiplex PCR assay was validated for rapid molecular differentiation of the Edwardsiella spp. affecting fish. Moreover, the limitations of relying on partial 16S rRNA for discrimination of Edwardsiella spp. and advantages of employing alternative single-copy genes gyrB and sodB for molecular identification and classification of Edwardsiella were demonstrated. Last, sodB sequencing confirmed that isolates previously defined as typical motile fish-pathogenic E. tarda are synonymous with Edwardsiella piscicida, while atypical nonmotile fish-pathogenic E. tarda isolates are equivalent to Edwardsiella anguillarum Fish-nonpathogenic E. tarda isolates are consistent with E. tarda as it is currently defined. These analyses help deconvolute the scientific literature regarding these organisms and provide baseline information to better facilitate proper taxonomic assignment and minimize erroneous identifications of Edwardsiella isolates in clinical and research settings.

Quantitative assessment of motor functions post-stroke: Responsiveness of upper-extremity robotic measures and its task dependence.

Technology aided measures offer a sensitive, accurate and time-efflcient approach for the assessment of sensorimotor function after neurological impairment compared to standard clinical assessments. This preliminary study investigated the relationship between task definition and its effect on robotic measures using a planar, two degree of freedom, robotic-manipulator (H-Man). Four chronic stroke participants (49.5±11.95 years, 2 Female, FMA: 37.5±13.96) and eight healthy control participants (26.25± 4.70 years, 2 Female) participated in the study. Motor functions were evaluated using line tracing and circle tracing tasks with dominant and nondominant hand of healthy and affected vs. non affected hand of stroke participants. The results show significant dependence of quantitative measures on investigated tasks.

Investigating anthelmintic efficacy against gastrointestinal nematodes in cattle by considering appropriate probability distributions for faecal egg count data.

The Faecal Egg Count Reduction Test (FECRT) is the most widely used field-based method for estimating anthelmintic efficacy and as an indicator of the presence of anthelmintic resistant nematodes in cattle, despite never having been validated against the gold standard of controlled slaughter studies. The objectives of this study were to assess the normality of cattle faecal egg count (FEC) data and their transformed versions, since confidence intervals used to aid the interpretation of the FECRT, are derived from data assumed to be normally distributed, and violation of this assumption could potentially lead to the misclassification of anthelmintic efficacy. Further, probability distributions and associated parameters were evaluated to determine those most appropriate for representing cattle FEC data, which could be used to estimate percentage reductions and confidence limits. FEC data were analysed from 2175 cattle on 52 farms using a McMaster method at two different diagnostic sensitivities (30 and 15 eggs per gram (epg)) and a sensitive centrifugal flotation technique (SCFT) with a sensitivity of 1 epg. FEC data obtained from all egg count methods were found to be non-normal even upon transformation; therefore, it would be recommended that confidence or credible intervals be generated using either a Bootstrapping or Bayesian approach, respectively, since analyses using these frameworks do not necessarily require the assumption of normality. FEC data obtained using the SCFT method were best represented by distributions associated with the negative binomial and hence arithmetic means could be used in FECRT calculations. Where FEC data were obtained with less sensitive counting techniques (i.e. McMaster 30 or 15 epg), zero-inflated distributions and their associated central tendency were the most appropriate and would be recommended to use, i.e. the arithmetic group mean divided by the proportion of non-zero counts present; otherwise apparent anthelmintic efficacy could be misrepresented.

Improving T Cell Expansion with a Soft Touch.

Protein-coated microbeads provide a consistent approach for activating and expanding populations of T cells for immunotherapy but do not fully capture the properties of antigen presenting cells. In this report, we enhance T cell expansion by replacing the conventional, rigid bead with a mechanically soft elastomer. Polydimethylsiloxane (PDMS) was prepared in a microbead format and modified with activating antibodies to CD3 and CD28. A total of three different formulations of PDMS provided an extended proliferative phase in both CD4+-only and mixed CD4+-CD8+ T cell preparations. CD8+ T cells retained cytotoxic function, as measured by a set of biomarkers (perforin production, LAMP2 mobilization, and IFN-γ secretion) and an in vivo assay of targeted cell killing. Notably, PDMS beads presented a nanoscale polymer structure and higher rigidity than that associated with conventional bulk material. These data suggest T cells respond to this higher rigidity, indicating an unexpected effect of curing conditions. Together, these studies demonstrate that adopting mechanobiology ideas into the bead platform can provide new tools for T cell based immunotherapy.