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OBJECTIVE: Adiposity has been hypothesized to interfere with the activity of bevacizumab (BEV), an anti-angiogenic agent. Measurements of adiposity, BMI, surface fat area (SFA), and visceral fat area (VFA) were investigated as prognostic of oncologic outcomes among patients treated with chemotherapy, with or without BEV, on GOG 218, a prospective phase III trial. METHOD: Pretreatment computed tomography (CT) for 1538 GOG 218 participants were analyzed. Proportional hazards models assessed association between adiposity and overall survival (OS) adjusted for other prognostic factors. The predictive value of adiposity as a function of BEV treatment was assessed in 1019 patients randomized to either chemotherapy (CT) + placebo (P) → P or CT + BEV → BEV. RESULTS: After adjusting for prognostic factors, SFA was not associated with the overall hazard of death (p = 0.981). There was a non-significant 0.1% (p = 0.062) increase in hazard of death associated with a unit increase in VFA. When comparing the treatment HRs for patients who did and did not receive BEV, there was no association with SFA (p = 0.890) or VFA (p = 0.106). A non-significant 0.8% increase in the hazard of death with unit increase in BMI (p = 0.086) was observed. BMI values were not predictive of a longer survival for patients with BEV vs placebo (p = 0.606). CONCLUSION: Measures of adiposity strongly correlated to one another but were not predictive of efficacy for BEV. VFA is a weak prognostic factor.

Acetylcholine (ACh) is a prevalent neurotransmitter throughout the nervous system. In the brain, ACh is widely regarded as a potent neuromodulator. In neurons, ACh signals are conferred through a variety of receptors that influence a broad range of neurophysiological phenomena such as transmitter release or membrane excitability. In sensory circuitry, ACh modifies neural responses to stimuli and coordinates the activity of neurons across multiple levels of processing. These factors enable individual neurons or entire circuits to rapidly adapt to the dynamics of complex sensory stimuli, underscoring an essential role for ACh in sensory processing. In the auditory system, histological evidence shows that acetylcholine receptors (AChRs) are expressed at virtually every level of the ascending auditory pathway. Despite its apparent ubiquity in auditory circuitry, investigation of the roles of this cholinergic network has been mainly focused on the inner ear or forebrain structures, while less attention has been directed at regions between the cochlear nuclei and midbrain. In this review, we highlight what is known about cholinergic function throughout the auditory system from the ear to the cortex, but with a particular emphasis on brainstem and midbrain auditory centers. We will focus on receptor expression, mechanisms of modulation, and the functional implications of ACh for sound processing, with the broad goal of providing an overview of a newly emerging view of impactful cholinergic modulation throughout the auditory pathway. [ABSTRACT FROM AUTHOR]

Background: In South Africa, the doctrine of informed consent (introduced by the South African courts, Cape Provincial Division) dictates that all reasonable patients be told of material risks and alternative options before consenting to medical treatment or procedural interventions. The reasonable patient standard requires that a patient be told of all material risks that would influence a reasonable person in determining whether or not to consent to the treatment. Regional anaesthesia, including peripheral nerve blocks (PNBs), provides a plethora of benefits to patients undergoing surgery but, due to potential risks involved, also requires informed consent. Studies have shown that South African anaesthetists do not regularly obtain adequate informed consent for these procedures. We implemented a quality improvement project to facilitate and enhance documented informed consent in our setting. Methods: A prospective quality improvement project was established at Groote Schuur Hospital, Cape Town, including all PNBs performed in two-week blocks before and after the introduction of a standardised regional anaesthesia informed consent form. The primary outcome, comparing the incidence of documented informed consent between the two groups, was assessed with the McNemar's test for differences in proportions. Regression analysis was used to explore the effect of prespecified confounders (such as documented consent taken, benefits discussed, alternatives discussed, complications discussed and whether autonomy was documented). Results: In total, 39 and 43 patients were included in the pre- and post-intervention groups, respectively. In our setting, anaesthetists were 4.16 times (95% confidence interval (CI) -6.67 to -2.98, p < 0.001) more likely to take documented informed consent when provided with a standardised form. The incidence of documented informed consent improved from 7.7% to 60.5%. Regression analysis showed that these confounders influenced the recall of the PNB consent and discussed benefits and complications. Overall, recall was mostly influenced when benefits were discussed with patients (95%CI -20.023 to -14.64, p < 0.001). Conclusion: Documentation of informed consent for PNBs in our setting is poor. A standardised consent form can facilitate the documentation of consent significantly. Patient recollection of the consent process also improved, specifically when benefits were discussed. [ABSTRACT FROM AUTHOR]

The medial nucleus of the trapezoid body (MNTB) has been intensively investigated as a primary source of inhibition in brainstem auditory circuitry. MNTB-derived inhibition plays a critical role in the computation of sound location, as temporal features of sounds are precisely conveyed through the calyx of Held/MNTB synapse. In adult gerbils, cholinergic signaling influences sound-evoked responses of MNTB neurons via nicotinic acetylcholine receptors (nAChRs; Zhang et al., 2021) establishing a modulatory role for cholinergic input to this nucleus. However, the cellular mechanisms through which acetylcholine (ACh) mediates this modulation in the MNTB remain obscure. To investigate these mechanisms, we used whole-cell current and voltage-clamp recordings to examine cholinergic physiology in MNTB neurons from Mongolian gerbils (Meriones unguiculatus) of both sexes. Membrane excitability was assessed in brain slices, in pre-hearing (postnatal days 9-13) and post-hearing onset (P18-20) MNTB neurons during bath application of agonists and antagonists of nicotinic (nAChRs) and muscarinic receptors (mAChRs). Muscarinic activation induced a potent increase in excitability most prominently prior to hearing onset with nAChR modulation emerging at later time points. Pharmacological manipulations further demonstrated that the voltage-gated K+ channel KCNQ (Kv7) is the downstream effector of mAChR activation that impacts excitability early in development. Cholinergic modulation of Kv7 reduces outward K+ conductance and depolarizes resting membrane potential. Immunolabeling revealed expression of Kv7 channels as well as mAChRs containing M1 and M3 subunits. Together, our results suggest that mAChR modulation is prominent but transient in the developing MNTB and that cholinergic modulation functions to shape auditory circuit development. [ABSTRACT FROM AUTHOR]

BACKGROUND: To determine whether time from surgery to initiation of chemotherapy impacts survival in advanced ovarian carcinoma. PATIENTS AND METHODS: This is a post-trial ad hoc analysis of Gynecologic Oncology Group protocol 218, a phase III randomized, double-blind, placebo-controlled trial designed to study the antiangiogenesis agent, bevacizumab, in primary and maintenance therapy for patients with newly diagnosed advanced ovarian carcinoma. Maximum attempt at debulking was an eligibility criterion. Stage III patients, not stage IV, were required to have gross macroscopic or palpable residual disease following surgery. The survival impact of time from surgery to initiation of chemotherapy was studied using Cox regression models and stratified by treatment arm, residual disease and other clinical and pathologic factors. RESULTS: One thousand seven hundred eighteen assessable patients were randomized (stage III (n = 1237); stage IV (n = 477), including those with complete resection (stage IV only, n = 81), low-volume residual (≤1 cm, n = 701), and suboptimal (>1 cm, n = 932). On multivariate analysis, time to chemotherapy initiation was predictive of overall survival (P < 0.001), with the complete resection group (i.e. stage IV) encountering an increased risk of death when time to initiation of chemotherapy exceeded 25 days (95% confidence interval 16.6-49.9 days). CONCLUSION: Survival for women with advanced ovarian cancer may be adversely affected when initiation of chemotherapy occurs >25 days following surgery. Our analysis applies to stage IV only as women with stage III who underwent complete resection were not eligible for this trial. These results, however, are consistent with Gompertzian first-order kinetics where patients with microscopic residual are most vulnerable. CLINICAL TRIALS IDENTIFIER: NCT00262847.