Coverage of education and training of traumatic brain injury-induced growth hormone deficiency in US residency and fellowship programs: a cross-sectional study

BACKGROUND

Hypopituitarism, including growth hormone deficiency (GHD), is a common sequela of traumatic brain injury (TBI). This study explored the coverage of education and training of TBI-induced hypopituitarism in general and GHD in particular, in postgraduate program curricula to identify knowledge gaps and opportunities.

METHODS

An online survey and qualitative interviews (focus groups) were conducted among endocrinology, neurology, and physiatry postgraduate program directors in the United States (US). The study received an IRB exemption.

RESULTS

A total of 419 fellowship and residency programs were invited to participate; 60 program directors completed the survey and 11 of these participated in the focus groups. About half of the respondents considered TBI-induced hypopituitarism important or fairly important to include in the curriculum, and nearly two-thirds considered it an appropriate training component. Neurology program directors considered education regarding hypopituitarism following TBI less important and relevant for their curricula compared with endocrinology and physiatry program directors. About half (53%) of the programs responded that they included TBI-induced pituitary disorders in their curricula. About two-thirds (68%) of endocrinology programs, compared with only one-quarter (25%) of neurology programs, covered TBI-induced pituitary disorders. Respondents identified multiple barriers to expanding hypopituitarism following TBI in the curriculum, including the rarity of condition and lack of time/room in the curriculum. Respondents reported that consensus clinical guidelines and the availability of more data on TBI-induced hypopituitarism, including GHD, would greatly impact the development of educational curricula on this topic.

CONCLUSIONS

To improve the management of TBI-induced hypopituitarism, education and training should be expanded in US fellowship and residency programs to prepare trainees to effectively screen, diagnose, and treat TBI-induced hypopituitarism, including GHD.

Tetracyclines for Treatment of Tularemia: A Case Series

Tetracyclines for tularemia have been associated with higher failure rates. There were 48 cases of tularemia at the University of Missouri between 1988 and 2015. We retrospectively analyzed 17 patients with tularemia who were successfully treated with tetracyclines, and 9 of these patients also underwent aspiration or incision and drainage.

Dysregulation of PINCH signaling in mesial temporal epilepsy

Mounting evidence suggests that inflammation is important in epileptogenesis. Particularly Interesting New Cysteine Histidine-rich (PINCH) protein is a highly conserved, LIM-domain protein known to interact with hyperphosphorylated Tau. We assessed PINCH expression in resected epileptogenic human hippocampi and further explored the relationships among PINCH, hpTau and associated kinases. Resected hippocampal tissue from 7 patients with mesial temporal lobe epilepsy (MTLE) was assessed by Western analyses to measure levels of PINCH and hyperphosphorylated Tau, as well as changes in phosphorylation levels of associated kinases AKT and GSK3β in comparison to normal control tissue. Immunolabeling was also conducted to evaluate PINCH and hpTau patterns of expression, co-localization and cell-type specific expression. Hippocampal PINCH was increased by 2.6 fold in the epilepsy cases over controls and hpTau was increased 10 fold over control. Decreased phospho-AKT and phospho-GSK3β in epilepsy tissue suggested involvement of this pathway in MTLE. PINCH and hpTau co-localized in some neurons in MTLE tissue. While PINCH was expressed by both neurons and astrocytes in MTLE tissue, hpTau was extracellular or associated with neurons. PINCH was absent from the serum of control subjects but readily detectable from the serum of patients with chronic epilepsy. Our study describes the expression of PINCH and points to AKT/GSK3β signaling dysregulation as a possible pathway in hpTau formation in MTLE. In view of the interactions between hpTau and PINCH, understanding the role of PINCH in MTLE may provide increased understanding of mechanisms leading to inflammation and MTLE epileptogenesis and a potential biomarker for drug-resistant epilepsy.

Expression of Signaling Molecules in Progressive Multifocal Leukoencephalopathy

INTRODUCTION

Progressive multifocal leukoencephalopathy (PML) is a debilitating demyelinating disease of the CNS caused by the infection and destruction of glial cells by JC virus (JCV) and is an AIDS-defining disease. Infection with JCV is common and most people acquire antibodies early in life. After initial infection, JCV remains in an asymptomatic persistent state and can be detected by PCR in many tissues including brain. A major question in PML pathogenesis is how the virus reactivates from persistence in HIV-1/AIDS. Our studies with primary cultures of glial cells have implicated transcription factors NF-κB and NFAT4, which bind to a unique site in the JCV noncoding control region and stimulate viral gene expression. Furthermore, these transcription factors are controlled by pathways downstream of proinflammatory cytokines, e.g., TNF-α activates NF-κB and stimulates JCV transcription.

OBJECTIVES

We hypothesize that HIV-1/PML initiation may involve reactivation of JCV by cytokine disturbances in the brain such as occur in HIV-1/AIDS. In this study, the objective was to evaluate HIV-1/PML clinical samples for expression of TNF-α and its receptors and subcellular localization of NF-κB p65 and NFAT4 compared to non-PML controls.

METHODS

We evaluated HIV-1/PML clinical samples and non-PML controls for expression of TNF-α and its receptors and subcellular localization of NF-κB p65 and NFAT4 using Western blot and immunohistochemistry.

RESULTS

Consistent with our hypothesis, compared to non-PML controls, HIV-1/PML tissue has high levels of TNF-α and TNFR1 expression and NF-κB and NFAT4 were preferentially localized to the nucleus.

CONCLUSION

The involvement of TNF-α/NF-κB/NFAT4 signaling in JCV regulation that we reported from experiments in cultured human glial cells may be clinically relevant in PML.

Micro-computed tomography assessment of vertebral column defects in retinoic acid-induced rat model of myelomeningocele

BACKGROUND

Myelomeningocele (MMC) is a common congenital malformation and the most severe form of spina bifida characterized by the protrusion of spinal cord and meninges through the spinal defect. Our objective was to improve the assessment of congenital vertebral defects in animal models of MMC using three-dimensional high resolution micro-computed tomography (micro-CT) imaging and quantitative digital analyses methods.

METHODS

Lumbosacral MMC was induced in fetal rats by exposure of pregnant mothers at embryonic day 10 (E10) to all-trans retinoic acid, and rats were examined at term (embryonic day 22). The axial skeleton was examined in an MMC model for the first time using ex vivo micro-CT at 10 μm voxel resolution to allow high resolution two-dimensional and three-dimensional characterization of anomalies in lumbosacral vertebrae, and quantitative assessment of distances between dorsal vertebral arches in lumbosacral regions in MMC rats, compared with normal controls.

RESULTS

We observed, in detail, skeletal defects in lumbosacral vertebra of MMC rats, including in the morphology of individual dorsal vertebral arches. Use of high resolution micro-CT has also enabled us to identify the delayed (nonfused) or absent ossification in vertebral bodies, increased fusion of adjacent lateral vertebral elements, and quantify the extent of dorsal arch widening. Distances between dorsal vertebral arches showed statistically significant increases from L5 through S4 in MMC rats, compared with normal controls.

CONCLUSION

High-resolution micro-CT combined with digital quantification methods is a powerful technique ideally suited for precise assessment of complex congenital skeletal abnormalities such as examined in this rodent model of MMC.

Changes in PINCH levels in the CSF of HIV+ individuals correlate with hpTau and CD4 count

Several studies report associations between the particularly interesting new cysteine histidine-rich (PINCH) protein and HIV-associated CNS disease. PINCH is detected in the CSF of HIV patients, and changes in levels during disease may be indicative of changes in disease status over time. PINCH binds hyperphosphorylated Tau (hpTau) in the brain and CSF, but little is known about the relevance of these interactions to HIV CNS disease. In this study, PINCH and hpTau levels were assessed in three separate CSF samples collected longitudinally from 20 HIV+ participants before and after initiating antiretroviral therapy or before and after a change in the treatment regimen. The intervals were approximately 1 (T2) and 3-7 (T3) months from the initial visit (baseline, T1). Correlational analyses were conducted for CSF levels of PINCH and hpTau and other variables including blood CD4 T-cell count, plasma and CSF viral burden, CSF neopterin, white blood cell (WBC) count, and antiretroviral CNS penetration effectiveness (CPE). Values for PINCH and hpTau were determined for each patient by calculating the fold changes between the second (T2) and third measurements (T3) from the baseline measurement (T1). Statistical analyses showed that the fold changes in CSF PINCH protein from T1 to T2 were significantly higher in participants with CD4 counts >200 cells/mm(3) at T2 compared to those with CD4 counts <200 cells/mm(3) at T2. This trend persisted irrespective of plasma or CSF viral burden or antiretroviral therapy CPE scores. The fold changes in PINCH levels between T1 and T2, and T1 and T3 were highly correlated to the fold changes in hpTau at T2/T1 and T3/T1 (correlation coefficient = 0.69, p < 0.001; correlation coefficient = 0.83, p < 0.0001, respectively). In conclusion, in these HIV participants, changes in CSF levels of PINCH appear to correlate with changes in blood CD4 count and with changes in CSF hpTau levels, but not with plasma or CSF viral burden, neopterin, WBC, or antiretroviral regimen CPE.

PINCH in the cellular stress response to tau-hyperphosphorylation

Particularly interesting new cysteine- histidine- rich protein (PINCH) is an adaptor protein that our data have shown is required for neurite extension under stressful conditions. Our previous studies also report that PINCH is recalled by neurons showing decreased levels of synaptodendritic signaling proteins such as MAP2 or synaptophysin in the brains of human immunodeficiency virus (HIV) patients. The current study addressed potential role(s) for PINCH in neurodegenerative diseases. Mass spectrometry predicted the interaction of PINCH with Tau and with members of the heat shock response. Our in vitro data confirmed that PINCH binds to hyperphosphorylated (hp) Tau and to E3 ubiquitin ligase, carboxy-terminus of heat shock-70 interacting protein. Silencing PINCH prior to induction of hp-Tau resulted in more efficient clearance of accumulating hp-Tau, suggesting that PINCH may play a role in stabilizing hp-Tau. Accumulation of hp-Tau is implicated in more than 20 neuropathological diseases including Alzheimer's disease (AD), frontotemporal dementia (FTD), and human immunodeficiency virus encephalitis (HIVE). Analyses of brain tissues from HIVE, AD and FTD patients showed that PINCH is increased and binds to hp-Tau. These studies address a new mechanism by which AD and HIV may intersect and identify PINCH as a contributing factor to the accumulation of hyperphosphorylated Tau.

Leach Rate Excursions in Borosilicate Glasses: Effects of Glass and Leachant Composition

Leach tests on borosilicate glasses using a partial-replenishment technique show that in certain cases large excursions in leach rate may appear at the end of periods ranging between 1 and 20 months. The extent and time of these leach rate transients are very sensitive to glass and leachant composition and to S/V ratio, and they may be eliminated by slight increases in Si and Al levels in the glass or by using a neutrally buffered leachant. This phenomenon, which may reflect cracking of the initial surface layer, can have a considerable effect on the results and complicate the modeling of leach tests which strongly reflect the extent of leaching during the early stages of glass/leachant interaction. However, these effects appear to have relatively little significance in the long term.