Carboplatin in Patients With Metastatic Castration-Resistant Prostate Cancer Harboring Somatic or Germline Homologous Recombination Repair Gene Mutations: Phase II Single-Arm Trial.

BACKGROUND: Approximately 20%-25% of patients with metastatic castration-resistant prostate cancer (mCRPC) harbor a deleterious germline or somatic mutation in the homologous recombination repair (HRR) pathway genes, which is involved in the repair of double-stranded DNA damage. Half of these mutations are germline, while the remaining are exclusively somatic. While polyadenosine 5'diphosphoribose [poly (ADP-ribose)] polymerase inhibitors, such as olaparib and rucaparib, are effective in this subgroup, their widespread use is limited due to the associated high cost, especially in resource-constrained settings. Notably, platinum agents like carboplatin have exquisite sensitivity to cells with defective DNA repair machinery. Carboplatin, a conventional, inexpensive chemotherapeutic agent, offers a potential alternative treatment in such patients. Several retrospective small case series support this hypothesis. However, there are no prospective clinical trials of carboplatin in patients with mCRPC with HRR mutations. OBJECTIVE: The primary objective is to assess the objective response rate of 3 weekly carboplatin treatments in patients with mCRPC harboring deleterious mutations in the HRR pathway genes and previously treated with a taxane or a novel antiandrogen agent. The secondary objectives include progression-free survival, health-related quality of life, and safety profile of carboplatin. METHODS: Patients diagnosed with mCRPC harboring HRR pathway mutations previously treated with docetaxel or novel antiandrogen agents (abiraterone, enzalutamide, apalutamide, or darolutamide) or both will be eligible. Genes involved directly or indirectly in the HRR pathway will be tested. In this single-arm phase II study, we will screen approximately 200 patients to enroll 49 patients, and carboplatin (dosing at the area under curve=5) will be administered every 3 weeks until progression or intolerable side effects. The primary end point will be assessed as the proportion of patients with a reduction of serum prostate-specific antigen by more than 50% from enrollment. Secondary outcomes include progression-free survival-soft-tissue disease progression (by response evaluation criteria in solid tumors, version 1.1, and bone lesion progression using Prostate Cancer Clinical Trials Working Group 3 criteria), health-related quality of life during carboplatin treatment using the Functional Assessment of Cancer Therapy-Prostate questionnaire and the European Organisation for Research and Treatment of Cancer questionnaire and safety profile of carboplatin (National Cancer Institute's Common Terminology Criteria for Adverse Events version 5.0). RESULTS: The trial started enrollment in September 2023. This trial is ongoing, and 12 patients have been recruited to date. All 49 participants will be enrolled according to plan. CONCLUSIONS: This prospective phase II trial represents a critical step toward addressing the therapeutic gap in patients with mCRPC harboring HRR pathway mutations, particularly in demographic regions with limited access to poly (ADP-ribose) polymerase inhibitors. Outcomes from this study will inform clinical practice and guide future phase III randomized trials, ultimately improving patient outcomes globally. TRIAL REGISTRATION: Clinical Trials Registry of India CTRI/2023/04/051507; https://ctri.nic.in/Clinicaltrials/pmaindet2.php?EncHid=Njc0NjU=&Enc=&userName=. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/54086.

Removal of Six Esophageal Metals in a Four-Month-Old Infant: A Rare Case.

This case report details the distinctive and demanding clinical situation involving a four-month-old female neonate. Her chief complaint was a two-day refusal to consume food orally, accompanied by episodes of vomiting following feedings and a sensation of choking in the throat. The referring physician suspected the presence of a foreign body in the patient's esophagus and advised a chest X-ray following a thorough examination. The presence of six hyperdense metallic foreign bodies in the upper, mid, and distal dorsal esophagus was confirmed by subsequent CT thorax imaging. This case was managed through the implementation of a multidisciplinary strategy. A decision was reached to conduct an endoscopic assessment; a substantial foreign object resembling a boulder was detected throughout the procedure, resulting in total obstruction of the esophageal lumen. Despite some challenges, this foreign object was effectively extracted by utilizing a Dormia basket. After that, endoscopy was used to detect five more metallic foreign bodies, all successfully eliminated endoscopically. The postoperative course was characterized by the 24-hour prophylactic Ryles tube insertion, followed by the resumption of breastfeeding. The infant's recovery and positive attitude on the second day following the operation indicate the case's successful resolution, emphasizing the criticality of a timely intervention in similar circumstances. This report underscores the clinical management and treatment of multiple metallic foreign bodies in a pediatric patient while also stressing the importance of prompt diagnosis and interprofessional collaboration in complex and exceptional cases.

Deep Transfer Learning for Ethnically Distinct Populations: Prediction of Refractive Error Using Optical Coherence Tomography.

INTRODUCTION: The mismatch between training and testing data distribution causes significant degradation in the deep learning model performance in multi-ethnic scenarios. To reduce the performance differences between ethnic groups and image domains, we built a deep transfer learning model with adaptation training to predict uncorrected refractive errors using posterior segment optical coherence tomography (OCT) images of the macula and optic nerve. METHODS: Observational, cross-sectional, multicenter study design. We pre-trained a deep learning model on OCT images from the B&VIIT Eye Center (Seoul, South Korea) (N = 2602 eyes of 1301 patients). OCT images from Poona Eye Care (Pune, India) were chronologically sorted into adaptation training data (N = 60 eyes of 30 patients) for transfer learning and test data (N = 142 eyes of 71 patients) for validation. Deep learning models were trained to predict spherical equivalent (SE) and mean keratometry (K) values via transfer learning for domain adaptation. RESULTS: Both adaptation models for SE and K were significantly better than those without adaptation (P < 0.001). In myopia/hyperopia classification, the model trained on circular optic disc OCT images yielded the best performance (accuracy = 74.7%). It also performed best in estimating SE with the lowest mean absolute error (MAE) of 1.58 D. For classifying the degree of corneal curvature, the optic nerve vertical algorithm performed best (accuracy = 65.7%). The optic nerve horizontal model achieved the lowest MAE (1.85 D) when predicting the K value. Saliency maps frequently highlighted the retinal nerve fiber layers. CONCLUSIONS: Adaptation training via transfer learning is an effective technique for estimating refractive errors and K values using macular and optic nerve OCT images from ethnically heterogeneous populations. Further studies with larger sample sizes and various data sources are needed to confirm the feasibility of the proposed algorithm.

Retching Without Vomiting With Acute Abdominal Distension: A Clinical Cue.

Gastric volvulus leading to acute gastric dilatation is a rare presentation of congenital diaphragmatic hernia. Urgent detorsion with gastropexy and closure of the diaphragmatic defect are essential to prevent further complications and recurrence. We present a rare case of an infant with acute gastric dilatation due to acute gastric volvulus secondary to congenital diaphragmatic hernia.

In-phase and mixed-phase measure synchronization of camphor rotors.

The numerical, analytical, and experimental analyses are presented for synchronizing two rotors under the Yukawa interaction. We report that the rotors exhibit in-phase and mixed-phase measure synchronizations for a pair of coupled rotors. Here, the analytical condition for synchronization is derived, tested numerically, and confirmed experimentally using coupled camphor infused rotors as a test bed. Moreover, the concept of measure synchronization is discussed. We report that, in conservative systems, not only the critical coupling parameter but initial conditions also play an essential role for estimating the measure synchronization region.

Catamenial epilepsy occurrence and patterns in a mixed population of women with epilepsy.

We evaluated the occurrence and distribution of patterns of catamenial epilepsy in a heterogenous cohort of women with epilepsy on no hormonal therapies, enrolled in a prospective, observational study. The primary aim of the study was pregnancy rate in women with epilepsy with no prior reproductive problems. In this analysis, we included women who recorded one or more menstrual cycles with one or more seizures. We measured progesterone concentrations for one to three cycles. We defined catamenial patterns as twofold or greater average daily seizure frequency around menstruation (C1), ovulation (C2), and for anovulatory cycles, from midcycle through menstruation (C3). Twenty-three of the 89 enrolled women with epilepsy were eligible for this analysis; 12 of 23 met criteria for catamenial epilepsy; five of 23 demonstrated only a C1 pattern, two of 23 only a C2 pattern, five of 23 a combined C1/C2 pattern, and the one woman with anovulatory cycles did not demonstrate a C3 pattern. There were no differences in likelihood of demonstrating a catamenial pattern between those who reported a prior catamenial pattern and those who did not (p = .855). This analysis demonstrates the utility of app-based tracking to determine a catamenial pattern. Larger prospective studies could confirm these findings and inform potential therapeutic trial designs for catamenial epilepsy.

Heart Failure With Stable Mildly-reduced Ejection Fraction: Prognosis and Predictors of Outcomes.

Heart failure with mildly-reduced ejection fraction (HFmrEF) of 40%-49% is an under-recognized type of heart failure. The prognosis and predictors of outcomes of stable mildly-reduced ejection fraction (EF) of 1 year are unclear. This is a retrospective study. Included patients had stable left ventricular ejection fraction (LVEF) for at least 1 year (n = 609) and were classified into 3 groups based on LVEF. Clinical outcome measures were all-cause mortality, cardiac mortality, and HF hospitalization (HFH). In patients with stable HFmrEF of one year, the predictors of clinical outcomes and hospital length of stay (LOS) were studied. Patients with stable HFmrEF had lower HFH rate compared to stable HFrEF with HR = 0.52 (95% CI = 0.39-0.70), P = 0.0001, and a higher HFH rate compared to stable HFpEF with HR = 1.23 (95% CI = 1.01-1.50), P = 0.032. Mortality rates were similar between all groups. In the stable HFmrEF patients, beta-blockers caused lower cardiac mortality, and CKD had fewer HFH. Unfavorable predictors were loop diuretics for mortality, and higher NYHA class for HFH. Smoking and CKD were associated with a longer hospital stay. Stable HFmrEF patients with at least one HF admission had higher mortality. Patients with stable HFmrEF had a lower HFH rate compared to stable HFrEF and higher HFH rate compared to stable HFpEF. In patients with stable HFmrEF, CKD, NYHA class, beta-blockers, and loop diuretics were predictors of clinical outcomes. Smoking and CKD were predictors of hospital LOS.

In Situ Imaging of Faujasite Surface Growth Reveals Unique Pathways of Zeolite Crystallization.

Zeolite crystallization occurs by complex processes involving a variety of possible mechanisms. The sol gel media used to prepare zeolites leads to heterogeneous mixtures of solution and solid states with diverse solute species. At later stages of zeolite synthesis when growth occurs predominantly from solution, classical two-dimensional nucleation and spreading of layers on crystal surfaces via the addition of soluble species is the dominant pathway. At earlier stages, these processes occur in parallel with nonclassical pathways involving crystallization by particle attachment (CPA). The relative roles of solution- and solid-state species in zeolite crystallization have been a subject of debate. Here, we investigate the growth mechanism of a commercially relevant zeolite, faujasite (FAU). In situ atomic force microscopy (AFM) measurements reveal that supernatant solutions extracted from a conventional FAU synthesis at various times do not result in growth, indicating that FAU growth predominantly occurs from the solid state through a disorder-to-order transition of amorphous precursors. Elemental analysis shows that supernatant solutions are significantly more siliceous than both the original growth mixture and the FAU zeolite product; however, in situ AFM studies using a dilute clear solution with a lower Si/Al ratio revealed three-dimensional growth of surfaces that is distinct from layer-by-layer and CPA pathways. This unique mechanism of growth differs from those observed in studies of other zeolites. Given that relatively few zeolite frameworks have been the subject of mechanistic investigation by in situ techniques, these observations of FAU crystallization raise the question whether its growth pathway is characteristic of other zeolite structures.

Effects of Electron Beam Sterilization on Polytetrafluoroethylene: Design of Experiments Study.

Polytetrafluoroethylene (PTFE) is a common polymer used in medical devices due to its exceptional properties (e.g., biocompatibility, inertness, chemical stability, low coefficient of friction). However, as a result of molecular weight reduction caused by the process of chain scission, it is known to be susceptible to radiation exposure and can rapidly lose strength and integrity. In this design of experiments study, the goal was to determine whether an operating window of conditions exist for electron beam (E-beam) radiation sterilization in which the degradation of PTFE is acceptably low. PTFE was tested for yield stress after exposure to radiation under different parameters (total dose [15-60 kGy], packaging atmosphere [air/nitrogen], and poststerilization accelerated aging [real-time equivalent of 1 and 3 years]). The results showed that total dose and packaging atmosphere were significant factors and indicated that the use of modified atmosphere packaging (vacuum sealing with nitrogen gas purge) can be a useful approach in increasing the stability of PTFE toward E-beam sterilization.

Self-assembling peptide nanofiber HIV vaccine elicits robust vaccine-induced antibody functions and modulates Fc glycosylation.

To develop vaccines for certain key global pathogens such as HIV, it is crucial to elicit both neutralizing and non-neutralizing Fc-mediated effector antibody functions. Clinical evidence indicates that non-neutralizing antibody functions including antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP) contribute to protection against several pathogens. In this study, we demonstrated that conjugation of HIV Envelope (Env) antigen gp120 to a self-assembling nanofiber material named Q11 induced antibodies with higher breadth and functionality when compared to soluble gp120. Immunization with Q11-conjugated gp120 vaccine (gp120-Q11) demonstrated higher tier 1 neutralization, ADCP, and ADCC as compared to soluble gp120. Moreover, Q11 conjugation altered the Fc N-glycosylation profile of antigen-specific antibodies, leading to a phenotype associated with increased ADCC in animals immunized with gp120-Q11. Thus, this nanomaterial vaccine strategy can enhance non-neutralizing antibody functions possibly through modulation of immunoglobulin G Fc N-glycosylation.

Generation of aperiodic motion due to sporadic collisions of camphor ribbons.

We present numerical and experimental results for the generation of aperiodic motion in coupled active rotators. The numerical analysis is presented for two point particles constrained to move on a unit circle under the Yukawa-like interaction. Simulations exhibit that the collision among the rotors results in chaotic motion of the rotating point particles. Furthermore, the numerical model predicts a route to chaotic motion. Subsequently, we explore the effect of separation between the rotors on their chaotic dynamics. The numerically calculated fraction of initial conditions which led to chaotic motion shed light on the observed effects. We reproduce a subset of the numerical observations with two self-propelled ribbons rotating at the air-water interface. A pinned camphor rotor moves at the interface due to the Marangoni forces generated by surface tension imbalance around it. The camphor layer present at the common water surface acts as chemical coupling between two ribbons. The separation distance of ribbons (L) determines the nature of coupled dynamics. Below a critical distance (L_{T}), rotors can potentially, by virtue of collisions, exhibit aperiodic oscillations characterized via a mixture of co- and counterrotating oscillations. These aperiodic dynamics qualitatively matched the chaotic motion observed in the numerical model.

Bleeding per rectum in pediatric population: A pictorial review.

Bleeding per rectum in children can be seen in congenital as well as acquired conditions that may require medical or surgical management. The present review article is aimed to discuss the imaging findings of some common and uncommon causes of bleeding per rectum in children.

Ingestion poisoning related lung injury- a pictorial review.

Poison ingestion is a medical emergency requiring immediate care in the emergency department. Respiratory symptoms with ingested poisons can occur due to aspiration, cardiopulmonary effects, or direct lung toxicity due to injury of the alveolar epithelium. Chest imaging (chest radiographs/CT) is usually performed in the emergency setting to evaluate such symptoms. It is often impossible to elicit the nature of the poison ingested by the patients due to their unconscious state. Identification of the culprit poison can expedite the patient's management towards a specific antidote or help understand the underlying mechanism causing the pulmonary symptoms. The imaging manifestations depend on the underlying mechanisms, varying for each ingested poison, forming an imaging signature which has not been adequately discussed in existing literature. Poisons like paraquat and organophosphate are important to differentiate as indiscriminate use of oxygen therapy in the former can exacerbate the lung injury caused by redox cycling. In this pictorial assay, we present the chest imaging spectrum of commonly ingested poisons, and further suggest algorithmic approach towards identification of common poisons based on their chest imaging.

A Study of Role of Ngal in Diagnosis and Staging the Severity of Diabetic Nephropathy in Type 2 Diabetes Mellitus Patients in Sms Medical College, Jaipur.

Present work was conducted to study of role of NGAL in diagnosis and staging the severity of diabetic nephropathy in type 2 diabetes mellitus patients to assess serum NGAL, urine albumin levels in diabetic patients with and without apparent nephropathy. MATERIAL: Comparative study conducted in the General Medicine department of SMS Hospital. INCLUSION CRITERIA: Patients of type 2 Diabetes mellitus. EXCLUSION CRITERIA: Patients consuming high protein diet, pregnancy, severe muscular exercises, orthostatic albuminuria, congestive heart failure, urinary tract infections, liver diseases. Patients with type 1 diabetes mellitus. OBSERVATION: The mean age of patient was 51.7 years. Here, HbA1c and NGAL were negatively correlated with each other with Pearson correlation -0.484 (p-value<0.05). In prediabetic patients mean NGAL was 407ng/ml and as HbA1c increases mean NGAL decreases 276.69 ng/ml (P-value <0.0012). As ACR increases mean NGAL increases significantly (P-value<0.05). CONCLUSION: Neutrophil gelatinase-associated lipocalin could be a renal function evaluation marker for patients with renal dysfunction and markers for detection of diabetic nephropathy in patients with type2 diabetes mellitus.

Obesity, Thyroid and OSA: An Intriguing Triangle.

The complex relationship between BMI, thyroid and its effects on OSA raises a question on how patients with suspected OSA should be evaluated. Some studies have described an association between thyroid disorders and OSA. Whether this is a direct effect of thyroid disorders, or it is indirectly related to BMI values is an important point to ponder. The aim of this study was to estimate the prevalence of thyroid disorders in relation to BMI in newly diagnosed patients with OSA (AHI > 5/h on diagnostic Polysomnography) at sleep lab of our tertiary care centre. In addition, we compared baseline characteristics of OSA patients with thyroid parameters. MATERIAL: In this hospital based observational study, recently diagnosed OSA on the basis of PSG showing AHI > 5/ h according to the AASM 2012 scoring rules and age more than 18 years were recruited from OPD and in-patients of SMS Medical College Jaipur. Patients on previous CPAP treatment, mixed or predominantly central sleep apnea, known diabetics and language barriers or cognitive or psychiatric disorders that made informed consent difficult to obtain were excluded. OBSERVATION: During the study period, 65 patients with treatment naïve OSA and a mean age of 52.28±10.92 year, a mean body mass index (BMI) of 34.73±7.20 kg/m2 underwent thyroid function tests. In the OSA patients, the prevalence of newly diagnosed clinical hypothyroidism was 12.3%. In Mild OSA the mean FT3 (ng/ml), FT4 (ng/dl), TSH (mIU/l) and mean AHI score was 3.10±0.71, 1.37±0.58, 3.64±1.37 and 7.74±3.55 respectively. Similarly, mean FT3 (ng/ml), FT4 (ng/dl), TSH (mIU/l) and mean AHI score were 2.97±0.93, 1.46±0.79, 6.33±8.05 and 17.42±88.90 respectively in moderate OSA and 3.32±0.58, 1.23±0.46, 3.55±1.82 and 45.54±21.38 respectively in severe OSA. There was a statistically significant difference between mild moderate and severe OSA regarding thyroid profile as well as BMI with p of <0.05. CONCLUSION: The prevalence of hypothyroidism was common among patients with OSA and the severity of OSA correlated with thyroid function tests and BMI.

Controlling Nucleation Pathways in Zeolite Crystallization: Seeding Conceptual Methodologies for Advanced Materials Design.

A core objective of synthesizing zeolites for widespread applications is to produce materials with properties and corresponding performances that exceed conventional counterparts. This places an impetus on elucidating and controlling processes of crystallization where one of the most critical design criteria is the ability to prepare zeolite crystals with ultrasmall dimensions to mitigate the deleterious effects of mass transport limitations. At the most fundamental level, this requires a comprehensive understanding of nucleation to address this ubiquitous materials gap. This Perspective highlights recent methodologies to alter zeolite nucleation by using seed-assisted protocols and the exploitation of interzeolite transformations to design advanced materials. Introduction of crystalline seeds in complex growth media used to synthesize zeolites can have wide-ranging effects on the physicochemical properties of the final product. Here we discuss the diverse pathways of zeolite nucleation, recent breakthroughs in seed-assisted syntheses of nanosized and hierarchical materials, and shortcomings for developing generalized guidelines to predict synthesis outcomes. We offer a critical analysis of state-of-the-art approaches to tailor zeolite crystallization wherein we conceptualize whether parallels between network theory and zeolite synthesis can be instrumental for translating key findings of individual discoveries across a broader set of zeolite crystal structures and/or synthesis conditions.

Spontaneous Pillaring of Pentasil Zeolites.

Conventional methods to prepare hierarchical zeolites depend upon the use of organic structure-directing agents and often require multiple synthesis steps with limited product yield and Brønsted acid concentration. Here, it is shown that the use of MEL- or MFI-type zeolites as crystalline seeds induces the spontaneous formation of self-pillared pentasil zeolites, thus avoiding the use of any organic or branching template for the crystallization of these hierarchical structures. The mechanism of formation is evaluated by time-resolved electron microscopy to provide evidence for the heterogeneous nucleation and growth of sequentially branched nanosheets from amorphous precursors. The resulting hierarchical zeolites have large external surface area and high percentages of external acid sites, which markedly improves their catalytic performance in the Friedel-Crafts alkylation and methanol to hydrocarbons reactions. These findings highlight a facile, commercially viable synthesis method to reduce mass-transport limitations and improve the performance of zeolite catalysts.

Insights from a Pan India Sero-Epidemiological survey (Phenome-India Cohort) for SARS-CoV2.

To understand the spread of SARS-CoV2, in August and September 2020, the Council of Scientific and Industrial Research (India) conducted a serosurvey across its constituent laboratories and centers across India. Of 10,427 volunteers, 1058 (10.14%) tested positive for SARS-CoV2 anti-nucleocapsid (anti-NC) antibodies, 95% of which had surrogate neutralization activity. Three-fourth of these recalled no symptoms. Repeat serology tests at 3 (n = 607) and 6 (n = 175) months showed stable anti-NC antibodies but declining neutralization activity. Local seropositivity was higher in densely populated cities and was inversely correlated with a 30-day change in regional test positivity rates (TPRs). Regional seropositivity above 10% was associated with declining TPR. Personal factors associated with higher odds of seropositivity were high-exposure work (odds ratio, 95% confidence interval, p value: 2.23, 1.92-2.59, <0.0001), use of public transport (1.79, 1.43-2.24, <0.0001), not smoking (1.52, 1.16-1.99, 0.0257), non-vegetarian diet (1.67, 1.41-1.99, <0.0001), and B blood group (1.36, 1.15-1.61, 0.001).

Management of patients after failed peroral endoscopic myotomy: a multicenter study.

BACKGROUND: Although peroral endoscopic myotomy (POEM) is highly effective for the management of achalasia, clinical failures may occur. The optimal management of patients who fail POEM is not well known. This study aimed to compare the outcomes of different management strategies in patients who had failed POEM. METHODS: This was an international multicenter retrospective study at 16 tertiary centers between January 2012 and November 2019. All patients who underwent POEM and experienced persistent or recurrent symptoms (Eckardt score > 3) were included. The primary outcome was to compare the rates of clinical success (Eckardt score ≤ 3) between different management strategies. RESULTS : 99 patients (50 men [50.5 %]; mean age 51.4 [standard deviation (SD) 16.2]) experienced clinical failure during the study period, with a mean (SD) Eckardt score of 5.4 (0.3). A total of 29 patients (32.2 %) were managed conservatively and 70 (71 %) underwent retreatment (repeat POEM 33 [33 %], pneumatic dilation 30 [30 %], and laparoscopic Heller myotomy (LHM) 7 [7.1 %]). During a median follow-up of 10 (interquartile range 3 - 20) months, clinical success was highest in patients who underwent repeat POEM (25 /33 [76 %]; mean [SD] Eckardt score 2.1 [2.1]), followed by pneumatic dilation (18/30 [60 %]; Eckardt score 2.8 [2.3]), and LHM (2/7 [29 %]; Eckardt score 4 [1.8]; P = 0.12). A total of 11 patients in the conservative group (37.9 %; mean Eckardt score 4 [1.8]) achieved clinical success. CONCLUSION : This study comprehensively assessed an international cohort of patients who underwent management of failed POEM. Repeat POEM and pneumatic dilation achieved acceptable clinical success, with excellent safety profiles.

Development of High-Throughput Assays for Evaluation of Hematopoietic Progenitor Kinase 1 Inhibitors.

Hematopoietic progenitor kinase 1 (HPK1), also referred to as mitogen-activated protein kinase kinase kinase kinase 1 (MAP4K1), is a serine/threonine kinase that negatively regulates T-cell signaling by phosphorylating Ser376 of Src homology 2 (SH2) domain-containing leukocyte protein of 76 kDa (SLP-76), a critical mediator of T-cell receptor activation. HPK1 loss of function mouse models demonstrated enhanced immune cell activation and beneficial antitumor activity. To enable discovery and functional characterization of high-affinity small-molecule HPK1 inhibitors, we have established high-throughput biochemical, cell-based, and novel pharmacodynamic (PD) assays. Kinase activity-based time-resolved fluorescence energy transfer (TR-FRET) assays were established as the primary biochemical approach to screen for potent inhibitors and assess selectivity against members of MAP4K and other closely related kinases. A proximal target engagement (TE) assay quantifying pSLP-76 levels as a readout and a distal assay measuring IL-2 secretion as a functional response were established using human peripheral blood mononuclear cells (PBMCs) from two healthy donors. Significant correlations between biochemical and cellular assays as well as excellent correlation between the two donors for the cellular assays were observed. pSLP-76 levels were further used as a PD marker in the preclinical murine model. This effort required the development of a novel ultrasensitive single-molecule array (SiMoA) assay to monitor pSLP-76 changes in mouse spleen.