Metagenomic characterization of the equine endometrial microbiome during anestrus.

The equine uterus is highly interrogated during estrus prior to breeding and establishing pregnancy. Many studies in mares have been performed during estrus under the influence of high estrogen concentrations, including the equine estrual microbiome. To date, it is unknown how the uterine microbiome of the mare is influenced by cyclicity; while, the equine vaginal microbiome is stable throughout the estrous cycle. We hypothesized that differences would exist between the equine endometrial microbiome of mares in estrus and anestrus. The aim of this study was two-fold: to characterize the resident endometrial microbiome of healthy mares during anestrus and to compare this with estrus. Double-guarded endometrial swabs were taken from healthy mares during estrus (n = 16) and in the following non-breeding season during anestrus (n = 8). Microbial population was identified using 16S rRNA sequencing. Our results suggest that the equine uterine microbiome in estrus has a low diversity and low richness, while during anestrus, a higher diversity and higher richness were seen compared to estrus. Despite this difference, both the estrus and anestrus endometrial microbiome were dominated by Proteobacteria, Firmicutes, and Bacteroidota. The composition of the microbial community between anestrus and estrus was significantly different. This may be explained by the difference in the composition of the endometrial immune milieu based on the stage of the cycle. Further research investigating the function of the equine endometrial microbiome and dynamics changes within the uterine environment is required.

Effect of Sampling Method on Detection of the Equine Uterine Microbiome during Estrus.

Bacterial endometritis is among the most common causes of subfertility in mares. It has a major economic impact on the equine breeding industry. The sensitivity of detecting uterine microbes using culture-based methods, irrespective of the sample collection method, double-guarded endometrial swab, endometrial biopsy, or uterine low-volume lavage (LVL), is low. Therefore, equine bacterial endometritis often goes undiagnosed. Sixteen individual mares were enrolled, and an endometrial sample was obtained using each method from all mares. After trimming, quality control and decontamination, 3824 amplicon sequence variants were detected in the dataset. We found using 16S rRNA sequencing that the equine uterus harbors a distinct resident microbiome during estrus. All three sampling methods used yielded similar results in composition as well as relative abundance at phyla (Proteobacteria, Firmicutes, and Bacteroidota) and genus (Klebsiella, Mycoplasma, and Aeromonas) levels. A significant difference was found in alpha diversity (Chao1) between LVL and endometrial biopsy, suggesting that LVL is superior at detecting the low-abundant (rare) taxa. These new data could pave the way for innovative treatment methods for endometrial disease and subfertility in mares. This, in turn, could lead to more judicious antimicrobial use in the equine breeding industry.

Calculation of the age of the first infection for skin sores and scabies in five remote communities in northern Australia.

Prevalence of skin sores and scabies in remote Australian Aboriginal communities remains unacceptably high, with Group A Streptococcus (GAS) the dominant pathogen. We aim to better understand the drivers of GAS transmission using mathematical models. To estimate the force of infection, we quantified the age of first skin sores and scabies infection by pooling historical data from three studies conducted across five remote Aboriginal communities for children born between 2001 and 2005. We estimated the age of the first infection using the Kaplan-Meier estimator; parametric exponential mixture model; and Cox proportional hazards. For skin sores, the mean age of the first infection was approximately 10 months and the median was 7 months, with some heterogeneity in median observed by the community. For scabies, the mean age of the first infection was approximately 9 months and the median was 8 months, with significant heterogeneity by the community and an enhanced risk for children born between October and December. The young age of the first infection with skin sores and scabies reflects the high disease burden in these communities.

Iterative development and the scope for plasticity: contrasts among trait categories in an adaptive radiation.

Phenotypic plasticity can influence evolutionary change in a lineage, ranging from facilitation of population persistence in a novel environment to directing the patterns of evolutionary change. As the specific nature of plasticity can impact evolutionary consequences, it is essential to consider how plasticity is manifested if we are to understand the contribution of plasticity to phenotypic evolution. Most morphological traits are developmentally plastic, irreversible, and generally considered to be costly, at least when the resultant phenotype is mis-matched to the environment. At the other extreme, behavioral phenotypes are typically activational (modifiable on very short time scales), and not immediately costly as they are produced by constitutive neural networks. Although patterns of morphological and behavioral plasticity are often compared, patterns of plasticity of life history phenotypes are rarely considered. Here we review patterns of plasticity in these trait categories within and among populations, comprising the adaptive radiation of the threespine stickleback fish Gasterosteus aculeatus. We immediately found it necessary to consider the possibility of iterated development, the concept that behavioral and life history trajectories can be repeatedly reset on activational (usually behavior) or developmental (usually life history) time frames, offering fine tuning of the response to environmental context. Morphology in stickleback is primarily reset only in that developmental trajectories can be altered as environments change over the course of development. As anticipated, the boundaries between the trait categories are not clear and are likely to be linked by shared, underlying physiological and genetic systems.

Prophylactic penicillin by the full moon: a novel approach in Central Australia that may help to reduce the risk of rheumatic heart disease.

INTRODUCTION: Uptake of penicillin prophylaxis to prevent recurrent rheumatic fever and its sequela rheumatic heart disease (RHD) is not optimal in the Northern Territory of Australia. The Full Moon Strategy (the Strategy) was introduced in the Central Australian region in June 2006 to improve the uptake of prophylactic penicillin: clients and healthcare workers were encouraged to use the full moon as a cue for the timing of the 4 weekly prophylactic penicillin injection. OBJECTIVE: To determine the impact and effectiveness of the Strategy on knowledge and uptake of benzathine penicillin prophylaxis for clients at risk of RHD, and for primary healthcare workers in Central Australia. METHODS: Clients at risk of RHD in four remote Aboriginal communities and the town camps of Alice Springs were identified from the RHD database. Consenting clients or their carers were interviewed about their knowledge of the Strategy and the health promotional tools used. Their healthcare records were then reviewed for prophylaxis uptake 2 years prior to and 2 years following the introduction of the Strategy. Primary healthcare workers in the four remote communities who were available at the time of the study visit were interviewed about their knowledge and use of the Strategy and the health promotional tools. RESULTS: Fifty RHD clients and 19 healthcare workers were interviewed. Most were aware of the flipchart but less than half knew of the calendar poster, hand-held card or radio advertisement. Prophylaxis uptake increased significantly from 47% in the 2 years prior to the introduction of the Strategy, to 57% 2 years after the Strategy was introduced. CONCLUSION: Introduction of the Strategy coincided with an improvement in uptake of prophylaxis but not around the time of the full moon. Uptake of benzathine penicillin remains inadequate and further innovative measures are needed to control rheumatic fever and its sequela in Aboriginal and Torres Strait Islander people.

Metabolic acidosis.

This article reviews acid-base homeostasis and discusses the approach to the acidotic patient, with special reference to problems commonly encountered in emergency practice. General principles of therapy are presented, and their application to specific types of life-threatening metabolic acidosis addressed. By extension, recommendations are made concerning the treatment of the acidosis associated with cardiac arrest. Finally, preliminary information is presented on promising new approaches to the treatment of metabolic acidosis that are currently under investigation.

Differential diagnosis of central retinal vein obstruction.

When obstruction of the central retinal vein presents in its florid hemorrhagic form, with disc edema and myriad, widespread retinal hemorrhages, there can be little doubt as to the proper diagnosis. However, when obstruction is incomplete, there may be confusion as to terminology, etiology, and proper treatment. "Venous-stasis retinopathy" was the term used in the early 1960s to describe the ophthalmoscopic changes recognized as resulting from the chronic ischemic changes induced by severe occlusive disease of the carotid artery. In the late 1970s, others began to use the term "venous-stasis retinopathy" to describe the incomplete or nonflorid type of central vein obstruction. These two conditions, although similar in appearance, have differences that allow their differentiation. The main differentiating feature is that the retinal artery pressure, as measured by ophthalmodynamometry or oculopneumoplethysmography, is always low in the retinopathy of carotid occlusive disease. These two conditions must be differentiated in order to manage the retinopathy properly as well as to recognize the potential for neurologic catastrophe.

Monitoring ophthalmology graduate education. The Residency Review Committee.

Formal monitoring of quality control in American graduate medical education is the task of the residency review committees (RRCs). The RRC for ophthalmology consists of nine members appointed by the American Board of Ophthalmology, the American Academy of Ophthalmology, and the American Medical Association. The RRC meets twice each year to determine the accreditation status of residency training programs. As of 1978, the residents ae board eligible only if they have graduated from accredited programs. The review process is based on data collected in standard hospital information forms and a site survey. An RRC member evaluates this information and makes a recommendation that is discussed and voted on by the nine-member RRC body. In response to pressures for greater quality control and regulatory visibility, the review process has been bolstered by improvements in the data-gathering forms and in the surveyors and by a revision of the minimum requirements for accreditation that provides clearer and more stringent guidelines.

Cloth-particle retinal emboli from artificial cardiac valves.

Two patients with prosthetic mitral valves had ocular complications. A 28-year-old woman suffered recurrent episodes of bilateral retinal embolization and consequent loss of useful vision over a period of two years despite therapeutic anticoagulation. Replacement of the valve was followed by cessation of the embolization. A 52-year-old man noted the abrupt onset of blurred vision in his right eye. Visual acuity was 6/6 (20/20) bilaterally, but the right eye had many retinal emboli of varying shapes. Both patients had long-standing mitral valve disease, but ocular symptoms developed only after the implantation of a cloth-covered mitral valve prosthesis. To the best of our knowledge, retinal emboli from cloth-covered cardiac valve prostheses have not been previously reported. Patients with such prostheses and ocular complaints who have adequate anticoagulation therapy should be carefully examined for retinal emboli. If emboli are present, valve dysfunction is possible and valve replacement may be necessary.

Resolution of venous stasis retinopathy after carotid artery bypass surgery.

Venous stasis retinopathy associated with carotid occlusive disease has been found to diminish or even disappear after carotid artery bypass surgery (superficial temporal artery to middle cerebral artery anastomosis). We present photographic documentation of these changes and subsequent resolution of the retinopathy in a patient who had bypass surgery. This resolution reflects the increased perfusion to the retina and to the cerebral hemisphere.

Unilateral visual loss in bright light. An unusual symptom of carotid artery occlusive disease.

Five patients with carotid artery occlusive disease had unilateral visual loss in bright light. All five had reduced retinal artery pressure on the side of the visual loss, and arteriograms showed either an occlusion or a high-grade stenosis of the ipsilateral internal carotid artery. Unilateral visual loss in bright light may indicate ipsilateral carotid artery occlusive disease and may reflect the inability of borderline circulation to sustain the increased retinal metabolic activity associated with exposure to bright light.

Ophthalmology and the carotid artery.

During the last three decades, carotid artery occlusive disease has changed from an obscure and rarely diagnosed condition to a clearly understood and frequently seen neurologic disorder. Its medical management and its surgical treatment are constantly improving. Ophthalmologists, together with neurologists, have contributed greatly to the understanding of the ocular signs and symptoms of carotid artery disease. Using his knowledge of these signs and symptoms, the ophthalmologist may make a significant contribution in the diagnosis and treatment of carotid artery occlusive disease.

The ocular aspects of bypass surgery of the carotid artery.

A new neurosurgical procedure, anastomosis of the superficial temporal artery to the middle cerebral artery, is being performed with increasing frequency. Over a 7-year period (1971 through 1977), 121 patients have undergone this operation in our institution. Ophthalmodynamometry may be of great help in identifying occlusion of an internal carotid artery. Progressing venous stasis retinopathy and ischemic orbital pain are believed to be indications for bypass surgery of the carotid artery.

The ocular aspects of carotid artery bypass surgery.

A new neurosurgical procedure, anastomosis of the superficial temporal artery to the middle cerebral artery, is being performed with increasing frequency. Over a 7-year period (1971 through 1977), 121 patients have undergone this operation in our institution. Ophthalmodynamometry may be of great help in identifying occlusion of an internal carotid artery. Progressing venous stasis retinopathy and ischemic orbital pain are believed to be indications for bypass surgery of the carotid artery.

Rapid resolution of venous stasis retinopathy after carotid endarterectomy.

A 60-year-old woman with ocular hypertension developed unilateral venous stasis retinopathy and neovascularization of the optic disk as the first signs of carotid occlusive disease. The retinopathy and the neovascularization disappeared rapidly and dramatically after carotid endarterectomy. Neovascularization in venous stasis retinopathy must be maintained by hypoxia or hypoperfusion, possibly through some intermediate substance such as a vasoproliferative factor.