14 research outputs found
Nuance and behavioral cogency: How the Visible Burrow System inspired the Stress-Alternatives Model and conceptualization of the continuum of anxiety
By creating the Visible Burrow System (VBS) Bob Blanchard found a way to study the interaction of genetics, physiology, environment, and adaptive significance in a model with broad validity. The VBS changed the way we think about anxiety and affective disorders by allowing the mechanisms which control them to be observed in a dynamic setting. Critically, Blanchard used the VBS and other models to show how behavioral systems like defense are dependent upon context and behavioral elements unique to the individual. Inspired by the VBS, we developed a Stress Alternatives Model (SAM) to further explore the multifaceted dynamics of the stress response with a dichotomous choice condition. Like the VBS, the SAM is a naturalistic model built upon risk assessment and defensive behavior, but with a choice of response: escape or submission to a large conspecific aggressor. The anxiety of novelty during the first escape must be weighed against fear of the aggressor, and a decision must be made. Both outcomes are adaptively significant, evidenced by a 50/50 split in outcome across several study systems. By manipulating the variables of the SAM, we show that a gradient of anxiety exists that spans the contextual settings of escaping an open field, escaping from aggression, and submitting to aggression. These findings correspond with increasing levels of corticosterone and increasing levels of NPS and BDNF in the central amygdala as the context changes.Whereas some anxiolytics were able to reduce the latency to escape for some animals, only with the potent anxiolytic drug antalarmin (CRF1R-blocker) and the anxiogenic drug yohimbine (α2 antagonist) were we able to reverse the outcome for a substantial proportion of individuals. Our findings promote a novel method for modeling anxiety, offering a distinction between low-and-high levels, and accounting for individual variability. The translational value of the VBS is immeasurable, and it guided us and many other researchers to seek potential clinical solutions through a deeper understanding of regional neurochemistry and gene expression in concert with an ecological behavioral model
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Strategies to increase testosterone in men seeking fertility.
Prevalence of testosterone deficiency is increasing in the adolescent and young adult male population. As the average paternal age rises, there is a significant population of men with hypogonadism seeking testosterone therapy wishing to achieve or maintain fertility potential. Identification of potential lifestyle modifications that may improve the testosterone deficiency is one of the initial interventions of the holistic strategy in treatment. This is followed by drug therapy; however, traditional testosterone therapy acts as a contraceptive by suppressing the hypothalamus-pituitary-gonadal (HPG) axis and therefore cannot be used as a treatment strategy. A solution has been the off-label use of selective estrogen receptor modulators, human chorionic gonadotropin (hCG), and anastrozole inhibitors to treat hypogonadal symptoms while increasing intratesticular testosterone, a necessity for spermatogenesis. Recently, a novel therapy, Natesto intranasal testosterone gel, has been shown to increase serum testosterone levels while maintaining semen parameters. This is hypothesized to be because of its short-acting properties having lesser effect on the HPG axis, in contrast to the long-acting properties of traditional testosterone therapy. It is important to differentiate hypogonadal men between those seeking to achieve or maintain fertility status because the drug therapy of choice differs. This can be accomplished by determining the levels of 17-hydroxyprogesterone (17-OHP), because it is a biomarker for intratesticular testosterone. Those with low 17-OHP may wish to initiate treatment with alternative therapies, whereas those with high 17-OHP may trial short-acting testosterone therapies. As the urologist's armamentarium continues to increase, better strategies to increase testosterone levels in men seeking fertility can be achieved
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POST-MORTEM EXAMINATION OF THE EFFECTS OF SEVERE ACUTE RESPIRATORY SYNDROME (SARS) ASSOCIATED CORONAVIRUS (SARS-COV) ON TESTIS
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Prospective Study of Nonbeneficial Care in Neurocritical Care Unit
We sought to determine whether a set of simple criteria can identify patients in the neuroscience intensive care unit (NICU) at high risk of poor outcome and delivery of nonbeneficial care early in the course of their illness. Secondarily, factors affecting limitation of care protocols were assessed.
We prospectively identified patients who were admitted to the NICU with partial loss of brainstem reflexes persisting for >24 hours due to an intrinsic lesion of the brain (trauma, stroke, hemorrhage, etc.).
The study included 102 patients. Seventy-two of them died after a mean of 16 days (median: 8 days), and 23 remained comatose, locked-in, or in a vegetative state. Four were conscious and following commands, while 3 were minimally conscious, episodically obeying simple commands. Three out of 4 conscious patients were young males with traumatic brain injuries. Patients who remained full code spent a mean of 22.2 days in the NICU, compared with 10.4 for those who had withdrawal of care (P = 0.022) and 11.9 for patients who received a do-not-resuscitate order (P = 0.045). Time to death did not differ significantly between the groups. Overall, institution of various limitations of care protocols correlated positively with older age (odds ratio [OR] = 1.07, P = 0.0008), being treated on the neurology service (OR = 4.4, P = 0.043), and having health insurance (OR = 5.4, P = 0.03).
We identified simple criteria that can be used to identify patients in the NICU setting for whom continued aggressive care is likely nonbeneficial. Our analysis revealed demographic, social, and economic factors correlating with proxies' willingness to consider limitation of care
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Primary Diffuse Leptomeningeal Melanomatosis: Case Report and Review of the Literature
Primary diffuse leptomeningeal melanomatosis (PDLM) is an extremely rare pathologic condition that can mimic several other neurologic disease states.
We report a rare case of PDLM without evidence of a primary focus. In addition, we performed a comprehensive review of the literature to describe all previously reported cases of PDLM.
In the reported case, making the diagnosis of PDLM was difficult. A brain and frontal dural biopsy was nondiagnostic. Computed tomography of the chest, abdomen, and pelvis did not show any distinct solitary mass. After a positron emission tomography scan was performed that showed lumbar sacral enhancement, lumbar dorsal rootlet biopsy was initiated, which was diagnostic of PDLM. Our literature review found 32 previously reported cases of PDLM. Sixteen cases (48.5%) had a distinct focus or mass discovered on imaging workup. The reported case was the seventeenth reported case of PDLM without a distinct focus or mass found on imaging workup.
PDLM is an extremely rare disease, and diagnosis is difficult because of nonspecific clinical, radiographic, and laboratory findings. In approximately half of cases, no distinct mass is shown on imaging workup, which may further complicate diagnosis. PDLM should be on the differential diagnosis for cases of diffuse dural enhancement. Neurosurgical intervention is often limited to ventriculoperitoneal shunting for increased intracranial pressure and dural and cranial biopsy to obtain diagnosis. If the initial biopsy is nondiagnostic, hypermetabolic activity as seen on positron emission tomography may be helpful to find an alternative biopsy site
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SARS-COV-2 ENDOTHELIAL DYSFUNCTION CAN CAUSE ERECTILE DYSFUNCTION: HISTOPATHOLOGICAL, IMMUNOHISTOCHEMICAL AND ULTRASTRUCTURAL STUDY OF THE HUMAN PENIS
Nuance and behavioral cogency: How the Visible Burrow System inspired the Stress-Alternatives Model and conceptualization of the continuum of anxiety
By creating the Visible Burrow System (VBS) Bob Blanchard found a way to study the interaction of genetics, physiology, environment, and adaptive significance in a model with broad validity. The VBS changed the way we think about anxiety and affective disorders by allowing the mechanisms which control them to be observed in a dynamic setting. Critically, Blanchard used the VBS and other models to show how behavioral systems like defense are dependent upon context and behavioral elements unique to the individual. Inspired by the VBS, we developed a Stress Alternatives Model (SAM) to further explore the multifaceted dynamics of the stress response with a dichotomous choice condition. Like the VBS, the SAM is a naturalistic model built upon risk assessment and defensive behavior, but with a choice of response: escape or submission to a large conspecific aggressor. The anxiety of novelty during the first escape must be weighed against fear of the aggressor, and a decision must be made. Both outcomes are adaptively significant, evidenced by a 50/50 split in outcome across several study systems. By manipulating the variables of the SAM, we show that a gradient of anxiety exists that spans the contextual settings of escaping an open field, escaping from aggression, and submitting to aggression. These findings correspond with increasing levels of corticosterone and increasing levels of NPS and BDNF in the central amygdala as the context changes.Whereas some anxiolytics were able to reduce the latency to escape for some animals, only with the potent anxiolytic drug antalarmin (CRF1R-blocker) and the anxiogenic drug yohimbine (α2 antagonist) were we able to reverse the outcome for a substantial proportion of individuals. Our findings promote a novel method for modeling anxiety, offering a distinction between low-and-high levels, and accounting for individual variability. The translational value of the VBS is immeasurable, and it guided us and many other researchers to seek potential clinical solutions through a deeper understanding of regional neurochemistry and gene expression in concert with an ecological behavioral model
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AN EVALUATION OF SEMEN PARAMETERS IN MEN WITH CONFIRMED COVID-19 INFECTION
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Histopathology and Ultrastructural Findings of Fatal COVID-19 Infections on Testis
To evaluate the presence and analyze the pathological changes within the testes of patients who died or recovered from severe acute respiratory syndrome coronavirus 2 (COVID-19) complications.
Testis tissue was collected from autopsies of COVID-19 positive (n=6) and negative men (n=3). Formalin-fixed paraffin-embedded tissues were stained with hematoxylin and eosin (H&E) and subjected to immunofluorescence for angiotensin-converting enzyme 2 (ACE-2) expression. Fluorescent-labeled tissue slides were imaged on a quantitative pathology scope with various zoom levels allowing for qualitative and quantitative interpretation. Tissue from four COVID-19 positive autopsy cases and a live seroconverted patient was imaged with transmission electron microscopy (TEM).
H&E histomorphology showed three of the six COVID-19 biopsies had normal spermatogenesis while the remaining three had impaired spermatogenesis. TEM showed the COVID-19 virus in testis tissue of one COVID-19 positive autopsy case and the live biopsy, H&E stain on the same autopsy case demonstrated interstitial macrophage and leukocyte infiltration. Immunofluorescent stained slides from six COVID-19 positive men demonstrated a direct association between increased quantitative ACE-2 levels and impairment of spermatogenesis.
The novel COVID-19 has an affinity for ACE-2 receptors. Since ACE-2 receptor expression is high in the testes, we hypothesized that COVID-19 is prevalent in testes tissue of infected patients. This study suggests the male reproductive tract, specifically the testes, may be targets of COVID-19 infection. We found an inverse association between ACE-2 receptor levels and spermatogenesis, suggesting a possible mechanism of how COVID-19 can cause infertility
Rising Black voices in urology - the next generation
In 2020, Nature Reviews Urology made a pledge to actively work towards improving diversity in our field. As we head into 2021, Black urologists make up only 2% of the US workforce in urology; this lack of representation is detrimental to the field as a whole and to the patients it serves. In this Viewpoint, which follows on from our previous article ‘Supporting Black voices in urology’, 12 medical students who have chosen to enter the field recount their experiences, describing their reasons for entering urology and why they chose particular programmes. As well as illustrating the importance of mentorship and representation, they also offer ideas on how urology programmes can better appeal to Black students, in order to encourage and support under-represented minorities into our specialty in the future