Efficacy and Safety of Dose-Escalated Alectinib in Patients With Metastatic ALK-Positive NSCLC and Central Nervous System Relapse on Standard-Dose Alectinib.

Introduction: Central nervous system (CNS) metastases remain a common challenge in patients with ALK-positive NSCLC. We previously reported reinduction of CNS responses using dose-intensified alectinib in two patients with CNS progression on standard-dose alectinib. Nevertheless, this strategy has not been assessed in larger cohorts. Methods: Patients were eligible for this retrospective study if they had metastatic ALK-positive NSCLC with CNS relapse on alectinib 600 mg twice daily dosing and subsequently received escalated dosing (900 mg twice daily) of alectinib. CNS efficacy was assessed per the modified Response Evaluation Criteria in Solid Tumors version 1.1. Results: Among 27 patients, median duration of dose-escalated alectinib was 7.7 months (95% confidence interval [CI]: 4.8-10.9), with median overall time-to-progression (TTP) of 7.1 months (95% CI: 4.4-9.6). Among 25 CNS response-assessable patients, CNS objective response rate was 12.0% (95% CI: 2.5-31.2) and CNS disease control rate was 92.0% (95% CI: 74.0-99.0), with median CNS duration of disease control of 5.3 months (95% CI: 3.4-8.3) and median CNS TTP of 7.1 months (95% CI: 4.4-9.6). Among four patients with measurable CNS disease at baseline, three experienced a best intracranial response of stable disease and one experienced intracranial partial response with CNS TTP ranging from 4.1 to 7.7 months. No patient required drug discontinuation due to treatment-related adverse event or experienced grade 3 or higher treatment-related adverse events. Conclusions: Dose-intensified alectinib was found to have tolerability and activity in patients with ALK-positive NSCLC who experienced CNS relapse on standard-dose alectinib and represents one clinically viable strategy for this population.

Hidden Flaws Behind Expert-Level Accuracy of Multimodal GPT-4 Vision in Medicine.

Recent studies indicate that Generative Pre-trained Transformer 4 with Vision (GPT-4V) outperforms human physicians in medical challenge tasks. However, these evaluations primarily focused on the accuracy of multi-choice questions alone. Our study extends the current scope by conducting a comprehensive analysis of GPT-4V's rationales of image comprehension, recall of medical knowledge, and step-by-step multimodal reasoning when solving New England Journal of Medicine (NEJM) Image Challenges - an imaging quiz designed to test the knowledge and diagnostic capabilities of medical professionals. Evaluation results confirmed that GPT-4V performs comparatively to human physicians regarding multi-choice accuracy (81.6% vs. 77.8%). GPT-4V also performs well in cases where physicians incorrectly answer, with over 78% accuracy. However, we discovered that GPT-4V frequently presents flawed rationales in cases where it makes the correct final choices (35.5%), most prominent in image comprehension (27.2%). Regardless of GPT-4V's high accuracy in multi-choice questions, our findings emphasize the necessity for further in-depth evaluations of its rationales before integrating such multimodal AI models into clinical workflows.

Kidney-Targeted Redox Scavenger Therapy Prevents Cisplatin-Induced Acute Kidney Injury.

Cisplatin-induced acute kidney injury (CI-AKI) is a significant co-morbidity of chemotherapeutic regimens. While this condition is associated with substantially lower survival and increased economic burden, there is no pharmacological agent to effectively treat CI-AKI. The disease is hallmarked by acute tubular necrosis of the proximal tubular epithelial cells primarily due to increased oxidative stress. We investigated a drug delivery strategy to improve the pharmacokinetics of an approved therapy that does not normally demonstrate appreciable efficacy in CI-AKI, as a preventive intervention. In prior work, we developed a kidney-selective mesoscale nanoparticle (MNP) that targets the renal proximal tubular epithelium. Here, we found that the nanoparticles target the kidneys in a mouse model of CI-AKI with significant damage. We evaluated MNPs loaded with the reactive oxygen species scavenger edaravone, currently used to treat stroke and ALS. We found a marked and significant therapeutic benefit with edaravone-loaded MNPs, including improved renal function, which we demonstrated was likely due to a decrease in tubular epithelial cell damage and death imparted by the specific delivery of edaravone. The results suggest that renal-selective edaravone delivery holds potential for the prevention of acute kidney injury among patients undergoing cisplatin-based chemotherapy.

Nanoreporter of an Enzymatic Suicide Inactivation Pathway.

Enzymatic suicide inactivation, a route of permanent enzyme inhibition, is the mechanism of action for a wide array of pharmaceuticals. Here, we developed the first nanosensor that selectively reports the suicide inactivation pathway of an enzyme. The sensor is based on modulation of the near-infrared fluorescence of an enzyme-bound carbon nanotube. The nanosensor responded selectively to substrate-mediated suicide inactivation of the tyrosinase enzyme via bathochromic shifting of the nanotube emission wavelength. Mechanistic investigations revealed that singlet oxygen generated by the suicide inactivation pathway induced the response. We used the nanosensor to quantify the degree of enzymatic inactivation by measuring response rates to small molecule tyrosinase modulators. This work resulted in a new capability of interrogating a specific route of enzymatic death. Potential applications include drug screening and hit-validation for compounds that elicit or inhibit enzymatic inactivation and single-molecule measurements to assess population heterogeneity in enzyme activity.

Congenital Granular Cell Epulis: Classic Presentation and Its Differential Diagnosis.

Congenital granular cell epulis (CGCE) is an uncommon lesion of unclear pathogenesis. It occurs predominantly in female newborns with a predilection site of the maxillary alveolar ridge. The mass enlarges prenatally but the growth arrests after birth. Histologically, CGCE is characterized by a proliferation of polygonal cells with eosinophilic, granular cytoplasm and eccentric, bland-appearing nuclei. It closely resembles adult granular cell tumor (GCT) microscopically and S-100 immunostain is often helpful in distinguishing the two (S-100-positive in GCT and S-100-negative in CGCE). Clinically, the lesion should also be distinguished from entities such as infantile myofibroma, rhabdomyoma, melanotic neuroectodermal tumor of infancy, peripheral odontogenic fibroma, and neurofibroma. CGCE demonstrates an excellent prognosis and has not been associated with any syndromes/genetic defects or malignant transformation. Clinicians and pathologists should be familiar with this rare entity and its differential diagnosis for accurate diagnosis and management.

Structure-induced switching of interpolymer adhesion at a solid-polymer melt interface.

Here we report a link between the interfacial structure and adhesive property of homopolymer chains physically adsorbed (i.e., via physisorption) onto solids. Polyethylene oxide (PEO) was used as a model and two different chain conformations of the adsorbed polymer were created on silicon substrates via the well-established Guiselin's approach: "flattened chains" which lie flat on the solid and are densely packed, and "loosely adsorbed polymer chains" which form bridges jointing up nearby empty sites on the solid surface and cover the flattened chains. We investigated the adhesion properties of the two different adsorbed chains using a custom-built adhesion testing device. Bilayers of a thick PEO overlayer on top of the flattened chains or loosely adsorbed chains were subjected to the adhesion test. The results revealed that the flattened chains do not show any adhesion even with the chemically identical free polymer on top, while the loosely adsorbed chains exhibit adhesion. Neutron reflectivity experiments corroborated that the difference in the interfacial adhesion is not attributed to the interfacial brodening at the free polymer-adsorbed polymer interface. Instead, coarse-grained molecular dynamics simulation results suggest that the tail parts of the loosely adsorbed chains act as "connector molecules", bridging the free chains and substrate surface and improving the interfacial adhesion. These findings not only shed light on the structure-property relationship at the interface, but also provide a novel approach for developing sticking/anti-sticking technologies through precise control of the interfacial polymer nanostructures.