Effect of accessibility of a genetic counselor on uptake of preimplantation genetic testing for aneuploidy (PGT-A) and carrier screening for patients undergoing in vitro fertilization

This retrospective cohort study assessed the accessibility of a genetic counselor on uptake of preimplantation genetic testing for aneuploidy (PGT-A) and carrier screening in a single academic Reproductive Endocrinology and Infertility (REI) clinic. A total of 420 patients were evaluated with 219 patients counseled by a REI physician only and 201 patients after the addition of a genetic counselor (GC) to the REI clinic team. Cycles initiated before hiring of a GC (pre-GC) were assessed from June 2018 to December 2018 and after integration of a GC (post-GC) from March 2019 to August 2019. Additionally, information regarding carrier screening was collected if available in the medical record. Results showed more patients utilized PGT-A post-GC (9.5% vs. 5.5%), although the difference between groups did not reach statistical significance (p = 0.12). Individuals who were screened post-GC or who started screening pre-GC and continued screening post-GC were screened for a larger number of conditions than if they were only screened pre-GC (median pre-GC = 3, post-GC = 27, pre- and post-GC = 274; p < 0.0001). The change in practice from using physician-only counseling to counseling with accessibility to a GC did not change the utilization of PGT-A in a single clinic.

Etiology- and region-specific characteristics of transependymal cerebrospinal fluid flow

OBJECTIVE

Transependymal flow (TEF) of CSF, often delineated as T2-weighted hyperintensity adjacent to the lateral ventricles on MRI, is a known imaging finding, usually in the setting of CSF flow disturbances. Specific radiological features of TEF and their relationships with clinical markers of hydrocephalus and underlying disease pathology are not known. Here, the authors describe the radiological features and clinical associations of TEF with implications for CSF circulation in the setting of intracranial pathology.

METHODS

After obtaining IRB review and approval, the authors reviewed the radiological records of all patients who underwent intracranial imaging with CT or MRI at St. Louis Children's Hospital, St. Louis, Missouri, between 2008 and 2019 to identify individuals with TEF. Then, under direct review of imaging, TEF pattern, degree, and location and underlying pathology and other radiological and clinical features pertaining to CSF circulation and CSF disturbances were noted.

RESULTS

TEF of CSF was identified in 219 patients and was most prevalent in the setting of neoplasms (72%). In 69% of the overall cohort, TEF was seen adjacent to the anterior aspect of the frontal horns and the posterior aspect of the occipital horns of the lateral ventricles, and nearly half of these patients also had TEF dorsal to the third ventricle near the splenium of the corpus callosum. This pattern was independently associated with posterior fossa medulloblastoma when compared with pilocytic astrocytoma (OR 4.75, 95% CI 1.43-18.53, p = 0.0157). Patients with congenital or neonatal-onset hydrocephalus accounted for 13% of patients and were more likely to have TEF circumferentially around the ventricles without the fronto-occipital distribution. Patients who ultimately required permanent CSF diversion surgery were more likely to have the circumferential TEF pattern, a smaller degree of TEF, and a lack of papilledema at the time of CSF diversion surgery.

CONCLUSIONS

CSF transmigration across the ependyma is usually restricted to specific periventricular regions and is etiology specific. Certain radiological TEF characteristics are associated with tumor pathology and may reflect impaired or preserved ependymal fluid handling and global CSF circulation. These findings have implications for TEF as a disease-specific marker and in understanding CSF handling within the brain.

Mechanical stress modulates NLRP3 pathway in macrophages

NLRP3 inflammasome activation releases the pro-inflammatory cytokine IL-1b and induces pyroptotic cell death. Dysregulated NLRP3 activation escalates inflammatory diseases such as acute lung injury (ALI), ventilator-induced lung injury (VILI), liver fibrosis, and idiopathic pulmonary fibrosis (IPF). These inflammatory disorders are associated with increased mechanical stress due to changing tissue compliance/stiffness. Resident macrophages sense this mechanical signal via a process known as “mechanotransduction”. However, the underlying mechanism of how mechanotransduction regulates the NLRP3 inflammasome is not fully known.

In this study, we are investigating that how NLRP3 pathway is regulated in lung resident macrophages during mechanical stress. To alter substrate compliance, macrophages are cultured on collagen-coated gels with various physiologically relevant stiffness (elastic moduli; measured in kiloPascal (kPa)) prior to NLRP3 activation. We have found that the NLRP3 inflammasome is sensitive to the substrate stiffness. NLRP3 induced IL-1β and pyroptosis-inducing gasdermin-D production were highest on the softest substrate (0.2 kPa) and decreased on a stiffer substrate (64 kPa). However, NLRC4 inflammasome activation was not mechano-responsive, suggesting ASC adaptor mediated cross signaling in mechanotransduction. Further analysis of gene expression using high-throughput RNA-sequencing, revealed altered expression of inflammatory bio-markers on macrophages when substrate stiffness was varied. Further examination of molecular interactions between adhesion-based mechanotransduction and NLRP3 signaling will help in understanding inflammatory diseases such as lung fibrosis.

AAI career in Immunology Fellowship, R01-AI104732 and R56 AI104732

L-plastin enhances NLRP3 inflammasome assembly and bleomycin-induced lung fibrosis

Macrophage adhesion and stretching have been shown to induce interleukin (IL)-1β production, but the mechanism of this mechanotransduction remains unclear. Here we specify the molecular link between mechanical tension on tissue-resident macrophages and activation of the NLRP3 inflammasome, which governs IL-1β production. NLRP3 activation enhances antimicrobial defense, but excessive NLRP3 activity causes inflammatory tissue damage in conditions such as pulmonary fibrosis and acute respiratory distress syndrome. We find that the actin-bundling protein L-plastin (LPL) significantly enhances NLRP3 assembly. Specifically, LPL enables apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC) oligomerization during NLRP3 assembly by stabilizing ASC interactions with the kinase Pyk2, a component of cell-surface adhesive structures called podosomes. Upon treatment with exogenous NLRP3 activators, lung-resident alveolar macrophages (AMs) lacking LPL exhibit reduced caspase-1 activity, IL-1β cleavage, and gasdermin-D processing. LPL^−/− mice display resistance to bleomycin-induced lung injury and fibrosis. These findings identify the LPL-Pyk2-ASC pathway as a target for modulation in NLRP3-mediated inflammatory conditions.

In this study, Joshi et al. identify a crucial modulator, L-plastin, in lung inflammation. L-plastin supports the macrophage inflammatory response to enhance lung fibrosis during lung injury by connecting inflammation and mechanical stimuli in a process called mechanotransduction. The findings from this study will help determine efficient targets for diagnosis and treatment of lung inflammatory diseases.

Representation of female neurosurgeons as abstract authors at neurological surgery conferences

OBJECTIVE

Female neurosurgeon representation has increased, but women still represent only 8.4% of neurosurgeons in the US. Women are significantly underrepresented as authors in neurosurgical and spine journals, a key indicator of professional success in academic medicine. In this study, the authors aimed to assess the gender diversity of first and last authors of accepted abstracts at neurosurgical conferences in 2015 and 2019.

METHODS

Annual meeting abstracts for 2015 and 2019 of the American Association of Neurological Surgeons (AANS), Congress of Neurological Surgeons (CNS), and pediatrics, spine, stereotactic and functional surgery, and cerebrovascular AANS/CNS subspecialty sections were obtained and analyzed for gender. Partial data were obtained for tumor and pain sections. Composite gender data were obtained from the societies. Percentage differences were calculated using comparison of proportions testing.

RESULTS

Overall, female neurosurgeons accounted for only 8.3% of first and 5.8% of last authors, and 7.2% of authors overall. The pediatrics section had the highest proportion of female neurosurgeons as first (13.7%) and last (12.4%) abstract authors, while the spine section had the lowest proportions of female neurosurgeon first (4.6%) and last (2.0%) authors. Qualitatively, a higher proportion of women were first authors, while a higher proportion of men were last authors. Overall, there was no significant change in female neurosurgeon authorship between 2015 and 2019. With regard to society demographics, female neurosurgeons accounted for only 6.3% of AANS membership. The pediatrics section had the highest proportion of female neurosurgeons at 18.1% and the stereotactic and functional surgery section had the lowest of the subspecialty sections (7.6%). While female neurosurgeons represented 12.6% of spine section membership, they represented only 4.7% of first authors (-7.9% difference; p < 0.0001) and 2.4% of last authors (-10.2% difference; p < 0.0001). For the 2019 cerebrovascular section, female neurosurgeons were underrepresented as presenting authors (5.8%) compared with their membership representation (14.8%, -9.0% difference; p = 0.0018).

CONCLUSIONS

Despite an increase in the number of female neurosurgeons, there has not been a corresponding increase in the proportion of female neurosurgeons as abstract authors at annual neurosurgery conferences, and female neurosurgeons remain underrepresented as authors compared with their male colleagues.

A randomized controlled trial to evaluate the use of a web-based application to manage medications during in vitro fertilization

OBJECTIVE

To evaluate the use of a web-based application that assists in medication management during in vitro fertilization (IVF) treatment.

DESIGN

Multicenter randomized controlled trial.

SETTING

University hospitals.

PATIENT(S)

Women undergoing IVF.

INTERVENTION(S)

Subjects were recruited to assess quality of life during IVF and were randomly assigned to use either the OnTrack application to assist with medication management or conventional medication management. Surveys were administered at four time points.

MAIN OUTCOME MEASURE(S)

Medication surplus, incidence of medication errors, amount of patient-initiated communication, and patient satisfaction.

RESULT(S)

A total of 153 women participated. The average number of portal messages and telephone calls was similar between groups. Twelve patients in the control group (12/69, 17.4%) and 8 patients in the case group (8/72, 11.1%) made medication errors. There were similar amounts of medication surplus in the two groups. The estimated cost of medication waste was $2,578 ± $2,056 in the control group and $2,554 ± $1,855 in the case group. Patient satisfaction was similar between the two groups.

CONCLUSION(S)

Use of a web-based application did not decrease medication errors, medication surplus, or patient-initiated messages. Many patients had a medication surplus, which can be an area of cost reduction during IVF.

CLINICAL TRIAL REGISTRATION NUMBER

Clinicaltrials.gov NCT03383848.

NLRP3 inflammasome activation in macrophages is mechanosensitive

Macrophages are innate immune cells that activate the NLRP3 inflammasome to induce inflammatory cytokine IL-1b production and pyroptotic cell death to combat infections. Dysregulated NLRP3 activation escalates inflammatory diseases under mechanical stress, such as ventilator induced injury (VLI), liver fibrosis, acute lung injury (ALI), and idiopathic pulmonary fibrosis (IPF). Macrophages reside in tissues via anchoring to the extracellular matrix (ECM), and change in adhesiveness tunes their inflammatory response via a process known as “mechanotransduction”. However, the underlying mechanism of how mechanical signaling regulates the NLRP3 inflammasome is not fully known. We have found that the NLRP3 inflammasome pathway in macrophages is sensitive to altered stiffness of the culture surface. We cultured bone-marrow derived macrophages (BMDMs) on collagen-coated polyacrylamide gels or silicone gels mimicking physiological tissue stiffness. We observed that NLRP3-induced IL-1b release was smallest on the softest gel (elastic moduli 0.2 kPa) and increased with a stiffer gel (64 kPa). Additionally, macrophages displayed increased adhesiveness and spreading on stiffer gels, indicating enhanced mechanical force. Further examination of how adhesion based-mechanotransduction modulates NLRP3 signaling will help in understanding inflammatory diseases associated with changing adhesive microenvironments such as lung fibrosis. We propose that increased stiffness during lung fibrosis exerts mechanical stress on macrophages and may promote NLRP3 inflammasome activation. Elucidating the mechanosensitivity of the NLRP3 inflammasome will aid in identifying treatment for such inflammatory diseases.

L-plastin supports macrophage NLRP3 inflammasome activation and pulmonary fibrosis

NLRP3 inflammasome induces IL-1β production and pyroptotic cell death in macrophages to fight against invading pathogens. However, excessive inflammasome activation promotes tissue fibrosis and inflammatory diseases such as acute lung injury, liver injury, and acute respiratory distress syndrome (ARDS). NLRP3 inflammasome activation has been extensively studied, but exact regulatory molecular mechanisms remain unclear.

We have found that the actin-bundling protein L-plastin (LPL) is required for efficient activation of the NLRP3 inflammasome pathway. In ex-vivo stimulation, lung resident alveolar macrophages (AMs) lacking LPL produced less IL-1β and IL-18 upon NLRP3 stimulation. LPL−/− AMs from ASC-citrine reporter mice exhibited reduced ASC speck formation after NLRP3 activation. Similarly, bone-marrow derived macrophages (BMDMs) displayed reduced ASC oligomerization. Downstream of ASC oligomerization, caspase-1 activity and downstream IL-1β and pyroptotic gasdermin-D processing were also reduced in LPL-deficient macrophages. Further, LPL−/− mice displayed reduced peritonitis after monosodium urate (MSU) treatment, an experimental NLRP3-induced inflammatory disease model. Since AMs are crucial for NLRP3-mediated lung fibrosis, we next examined NLRP3-dependent bleomycin-induced lung injury. We found that LPL−/− mice responded mildly to bleomycin and exhibited significantly reduced fibrosis development. Thus, we identify a previously unknown significant function of LPL in regulating NLRP3 inflammasome signaling in macrophages. This finding presents LPL as a potential target for diagnosis and treatment for NLRP3-associated inflammatory disorders such as ARDS, COPD and lung fibrosis.

The actin-bundling protein L-plastin regulates NLRP3 inflammasome activation in macrophages

In macrophages, inflammasome pathways induce IL-1β release and pyroptotic cell death to clear infections. For example, NLRP3 inflammasome activation in lung resident alveolar macrophages (AMs) is crucial in controlling pneumonia. We have found that mice lacking the actin-bundling protein L-plastin (LPL−/−) mice are highly susceptible to Streptococcus pnuemoniae lung infection and produce less IL-1β. LPL is also required for podosome formation. Podosomes are integrin-based sites of adhesion that anchor the actin cytoskeleton of AMs to the extracellular environment. As such, AMs can sense their mechanical environment via podosomes. We have found that AMs lacking LPL exhibit defective NLRP3 inflammasome activation in ex-vivo stimulation. Specifically, LPL is required for ASC oligomerization and downstream IL-1β processing after NLRP3 assembly. Since LPL also supports mechanosensitive integrin signaling, we hypothesized that LPL might link contact-based mechanosensation to inflammasome activation in macrophages. To test this hypothesis, we challenged LPL−/− mice with bleomycin, as bleomycin-induced lung injury and fibrosis is thought to be dependent upon NLRP3 activation. LPL−/− mice were resistant to bleomycin-induced lung injury, suggesting a previously unrecognized mechanosensitive mechanism regulating inflammasome activation in macrophages. We propose that the increased lung stiffness in fibrotic lung exerts mechanical stress on AMs and thus may contribute in inflammasome signaling. Increased understanding how mechanical signaling regulates may thus aid in developing therapies to treat lung pathologies i.e. acute respiratory distress syndrome (ARDS), COPD and lung fibrosis.