Ebola Virus Localization in the Macaque Reproductive Tract during Acute Ebola Virus Disease.

Sexual transmission of Ebola virus (EBOV) has been demonstrated more than a year after recovery from the acute phase of Ebola virus disease (EVD). The mechanisms underlying EBOV persistence and sexual transmission are not currently understood. Using the acute macaque model of EVD, we hypothesized EBOV would infect the reproductive tissues and sought to localize the infection in these tissues using immunohistochemistry and transmission electron microscopy. In four female and eight male macaques that succumbed to EVD between 6 and 9 days after EBOV challenge, we demonstrate widespread EBOV infection of the interstitial tissues and endothelium in the ovary, uterus, testis, seminal vesicle, epididymis, and prostate gland, with minimal associated tissue immune response or organ pathology. Given the widespread involvement of EBOV in the reproductive tracts of both male and female macaques, it is reasonable to surmise that our understanding of the mechanisms underlying sexual transmission of EVD and persistence of EBOV in immune-privileged sites would be facilitated by the development of a nonhuman primate model in which the macaques survived past the acute stage into convalescence

Simian hemorrhagic fever virus infection of rhesus macaques as a model of viral hemorrhagic fever: Clinical characterization and risk factors for severe disease

AbstractSimian Hemorrhagic Fever Virus (SHFV) has caused sporadic outbreaks of hemorrhagic fevers in macaques at primate research facilities. SHFV is a BSL-2 pathogen that has not been linked to human disease; as such, investigation of SHFV pathogenesis in non-human primates (NHPs) could serve as a model for hemorrhagic fever viruses such as Ebola, Marburg, and Lassa viruses. Here we describe the pathogenesis of SHFV in rhesus macaques inoculated with doses ranging from 50PFU to 500,000PFU. Disease severity was independent of dose with an overall mortality rate of 64% with signs of hemorrhagic fever and multiple organ system involvement. Analyses comparing survivors and non-survivors were performed to identify factors associated with survival revealing differences in the kinetics of viremia, immunosuppression, and regulation of hemostasis. Notable similarities between the pathogenesis of SHFV in NHPs and hemorrhagic fever viruses in humans suggest that SHFV may serve as a suitable model of BSL-4 pathogens

Exercise and Type 2 Diabetes: The American College of Sports Medicine and the American Diabetes Association: joint position statement

Although physical activity (PA) is a key element in the prevention and management of type 2 diabetes, many with this chronic disease do not become or remain regularly active. High-quality studies establishing the importance of exercise and fitness in diabetes were lacking until recently, but it is now well established that participation in regular PA improves blood glucose control and can prevent or delay type 2 diabetes, along with positively affecting lipids, blood pressure, cardiovascular events, mortality, and quality of life. Structured interventions combining PA and modest weight loss have been shown to lower type 2 diabetes risk by up to 58% in high-risk populations. Most benefits of PA on diabetes management are realized through acute and chronic improvements in insulin action, accomplished with both aerobic and resistance training. The benefits of physical training are discussed, along with recommendations for varying activities, PA-associated blood glucose management, diabetes prevention, gestational diabetes mellitus, and safe and effective practices for PA with diabetes-related complications

West Nile Virus Spreads Transsynaptically within the Pathways of Motor Control: Anatomical and Ultrastructural Mapping of Neuronal Virus Infection in the Primate Central Nervous System

<div><p>Background</p><p>During recent West Nile virus (WNV) outbreaks in the US, half of the reported cases were classified as neuroinvasive disease. WNV neuroinvasion is proposed to follow two major routes: hematogenous and/or axonal transport along the peripheral nerves. How virus spreads once within the central nervous system (CNS) remains unknown.</p><p>Methodology/Principal Findings</p><p>Using immunohistochemistry, we examined the expression of viral antigens in the CNS of rhesus monkeys that were intrathalamically inoculated with a wild-type WNV. The localization of WNV within the CNS was mapped to specific neuronal groups and anatomical structures. The neurological functions related to structures containing WNV-labeled neurons were reviewed and summarized. Intraneuronal localization of WNV was investigated by electron microscopy. The known anatomical connectivity of WNV-labeled neurons was used to reconstruct the directionality of WNV spread within the CNS using a connectogram design. Anatomical mapping revealed that all structures identified as containing WNV-labeled neurons belonged to the pathways of motor control. Ultrastructurally, virions were found predominantly within vesicular structures (including autophagosomes) in close vicinity to the axodendritic synapses, either at pre- or post-synaptic positions (axonal terminals and dendritic spines, respectively), strongly indicating transsynaptic spread of the virus between connected neurons. Neuronal connectivity-based reconstruction of the directionality of transsynaptic virus spread suggests that, within the CNS, WNV can utilize both anterograde and retrograde axonal transport to infect connected neurons.</p><p>Conclusions/Significance</p><p>This study offers a new insight into the neuropathogenesis of WNV infection in a primate model that closely mimics WNV encephalomyelitis in humans. We show that within the primate CNS, WNV primarily infects the anatomical structures and pathways responsible for the control of movement. Our findings also suggest that WNV most likely propagates within the CNS transsynaptically, by both, anterograde and retrograde axonal transport.</p></div

WNV-labeled neurons in the spinal cord.

<p>Representative images of WNV-labeled neurons in the cervical (<b>A</b> and <b>D</b>), thoracic (<b>B</b> and <b>E</b>), and lumbar regions (<b>C</b> and <b>F</b>) of the spinal cord are shown on indicated dpi. Approximate boundaries of the spinal cord gray matter are outlined in the overview images. Clarke’s column is shown by magenta overlay in <b>E</b>. Round insets show the corresponding circled areas at higher magnification. Note that the majority of WNV-labeled neurons occupy a medial portion of the Clarke’s column. Vh, ventral horns; CC, Clarke’s column. Bars in overview images: 1000 μm. Bars in the round insets: 100 μm.</p

WNV-labeled neurons in the cerebellar cortex.

<p>Original views of WNV-labeled neurons at 7 dpi (<b>A</b>) and 9 dpi (<b>C</b>). <b>B</b> and <b>D</b> show the corresponding markup images of <b>A</b> and <b>C</b> after applied “WNV-labeled cell segmentation” image analysis algorithm (WNV immunoreactivity: red, strong; orange, moderate; yellow, weak; negative, blue). Note an increasing WNV immunoreactivity in the somatodendritic compartments of Purkinje cells from 7 dpi to 9 dpi (compare <b>B</b> and <b>D</b>) and variable immunoreactivity in small groups of granule neurons only at 9 dpi (<b>D</b>). M, molecular layer; P, Purkinje cell layer; G, granule cell layer. Scale bars: 100 μm.</p

Ultrastructural localization of WNV particles in the cerebellar cortex.

<p>Shown are electron microscopy images of dendritic arbors of Purkinje cells (PCs). Some asymmetric axo-dendritic synapses are shown by green overlays. In panels (<b>A</b> and <b>D</b>): white arrows point to the postsynaptic density (PSD) and black arrows show synaptic clefts (SC). In some panels the groups of virions are outlined by yellow dashed circles/ovals. Insets in (<b>A</b>, <b>B</b>, <b>E</b>, and <b>F</b>) show the corresponding red boxed areas at higher magnification. (<b>A</b>) Bifurcating PC dendrite contains multiple spherical electron-dense virions. Inset shows several virions in close vicinity to the dendritic spine (DS) which is synapsing with axonal terminal (AT). (<b>B</b>) A shaft of another PC dendrite is shown at higher magnification. Virions can be seen in association with the hypolemmal cisternae of the agranular endoplasmic reticulum (AER; white arrows) and microtubule structures (white arrowheads). Inset shows three virions adjacent to the AER (white arrow) and one virion inside the vesicle adjacent to microtubules covered with a “cottony” material. (<b>C</b> and <b>D</b>) Virions within PC dendrites are found in close vicinity to synapses. (<b>E</b>) Virion-containing vesicles are in the presynaptic position in the axonal terminal. Another axonal terminal in the lower right corner contains synaptic vesicles (black arrows) and one large dense-core vesicle (black arrowhead). (<b>F</b>) Virions are enclosed within the autophagosome-like vesicles with double-layered membrane. Inset shows one such vesicle at presynaptic position (~40 nm away from the active zone of the synapse). M, mitochondria. Scale bars: 100 nm.</p

Proposed directionality of WNV spread based on the neuroanatomical connectivity and time of immunohistochemical virus detection.

<p>The connectograms illustrate most probable routes and directionality of WNV spread within the CNS in our NHP model of neuroinfection at 7 dpi (<b>A</b>) and 9/10 dpi (<b>B</b>). Construction and elements of the connectogram are described in Materials and Methods and text. Each arrow has the same color as the structure in the ring from which it originates. The circled numbers 1 to 4 represent most probable “order” of infected neurons within the corresponding anatomical structures. Solid arrows indicate most probable routes of anterograde spread; dashed arrows indicate most probable routes of retrograde spread. White lines indicate the possibility of both, anterograde and retrograde virus spread, due to existence of reciprocal connections between the same orders of neurons. <b><i>Abbreviations</i>:</b> Mthal, motor thalamus; BG, basal ganglia; CSMN, corticospinal motor neurons; SNC, substantia nigra pars compacta; RnM, red nucleus magnocellular; SMN, spinal motor neurons (C—cervical; T—thoracic; L—lumbar); CC, Clarke’s column; DCN, deep cerebellar nuclei; ACu, Accessory cuneate nucleus; IO, inferior olivary nuclear complex; MeRF, Medullary reticular formation; Ve, vestibular nuclei; PN, pontine nuclei.</p

Summary of neurological functions related to the structures containing WNV-labeled neurons.

<p>Summary of neurological functions related to the structures containing WNV-labeled neurons.</p