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1.
Front Pharmacol ; 15: 1369659, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086396

RESUMO

COVID-19 is currently considered the ninth-deadliest pandemic, spreading through direct or indirect contact with infected individuals. It has imposed a consistent strain on both the financial and healthcare resources of many countries. To address this challenge, there is a pressing need for the development of new potential therapeutic agents for the treatment of this disease. To identify potential antiviral agents as novel dual inhibitors of SARS-CoV-2, we retrieved 404 alkaloids from 12 selected medicinal antiviral plants and virtually screened them against the renowned catalytic sites and favorable interacting residues of two essential proteins of SARS-CoV-2, namely, the main protease and spike glycoprotein. Based on docking scores, 12 metabolites with dual inhibitory potential were subjected to drug-likeness, bioactivity scores, and drug-like ability analyses. These analyses included the ligand-receptor stability and interactions at the potential active sites of target proteins, which were analyzed and confirmed through molecular dynamic simulations of the three lead metabolites. We also conducted a detailed binding free energy analysis of pivotal SARS-CoV-2 protein inhibitors using molecular mechanics techniques to reveal their interaction dynamics and stability. Overall, our results demonstrated that 12 alkaloids, namely, adouetine Y, evodiamide C, ergosine, hayatinine, (+)-homoaromoline, isatithioetherin C, N,alpha-L-rhamnopyranosyl vincosamide, pelosine, reserpine, toddalidimerine, toddayanis, and zanthocadinanine, are shortlisted as metabolites based on their interactions with target proteins. All 12 lead metabolites exhibited a higher unbound fraction and therefore greater distribution compared with the standards. Particularly, adouetine Y demonstrated high docking scores but exhibited a nonspontaneous binding profile. In contrast, ergosine and evodiamide C showed favorable binding interactions and superior stability in molecular dynamics simulations. Ergosine demonstrated exceptional performance in several key pharmaceutical metrics. Pharmacokinetic evaluations revealed that ergosine exhibited pronounced bioactivity, good absorption, and optimal bioavailability. Additionally, it was predicted not to cause skin sensitivity and was found to be non-hepatotoxic. Importantly, ergosine and evodiamide C emerged as superior drug candidates for dual inhibition of SARS-CoV-2 due to their strong binding affinity and drug-like ability, comparable to known inhibitors like N3 and molnupiravir. This study is limited by its in silico nature and demands the need for future in vitro and in vivo studies to confirm these findings.

2.
Front Mol Med ; 4: 1310002, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086435

RESUMO

Since the FDA's approval of chimeric antigen receptor (CAR) T cells in 2017, significant improvements have been made in the design of chimeric antigen receptor constructs and in the manufacturing of CAR T cell therapies resulting in increased in vivo CAR T cell persistence and improved clinical outcome in certain hematological malignancies. Despite the remarkable clinical response seen in some patients, challenges remain in achieving durable long-term tumor-free survival, reducing therapy associated malignancies and toxicities, and expanding on the types of cancers that can be treated with this therapeutic modality. Careful analysis of the biological factors demarcating efficacious from suboptimal CAR T cell responses will be of paramount importance to address these shortcomings. With the ever-expanding toolbox of experimental approaches, single-cell technologies, and computational resources, there is renowned interest in discovering new ways to streamline the development and validation of new CAR T cell products. Better and more accurate prognostic and predictive models can be developed to help guide and inform clinical decision making by incorporating these approaches into translational and clinical workflows. In this review, we provide a brief overview of recent advancements in CAR T cell manufacturing and describe the strategies used to selectively expand specific phenotypic subsets. Additionally, we review experimental approaches to assess CAR T cell functionality and summarize current in silico methods which have the potential to improve CAR T cell manufacturing and predict clinical outcomes.

3.
Health Sci Rep ; 7(8): e2258, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39086505

RESUMO

Background and aims: In low- and middle-income countries (LMICs), a shortage of skilled surgical practitioners hampers healthcare delivery, impacting well-being and economic growth. Surgical mentorship programs offer a promising solution but face challenges in implementation. This review aims to comprehensively assess the impact of surgical mentorship programs in LMICs and identify challenges and opportunities for their development and implementation. Methods: A thorough literature search was conducted from 2000 to 2023 using multiple databases, focusing on surgical mentorship programs in LMICs. Inclusion criteria encompassed full-text articles in English that demonstrated characteristics of mentorship. Rigorous exclusion criteria were applied to ensure high-quality evidence inclusion. Results: Surgical mentorship programs in LMICs strengthen local surgical capacity, improve surgical skills and patient outcomes, optimize resources and technology utilization, and positively impact medical students aspiring to be surgeons. However, challenges such as resistance to change, resource limitations, financial constraints, logistical and technological challenges, and time constraints hinder their implementation. Conclusion: Despite challenges, surgical mentorship programs hold promise for enhancing surgical capacity and healthcare quality in LMICs. Standardized metrics for accountability, innovative funding mechanisms, collaborative partnerships for scalability, interdisciplinary integration, and leveraging virtual mentorship programs are key strategies to overcome challenges and foster sustainable learning cultures, ultimately contributing to improved healthcare equity and quality in low-resource settings.

4.
Indian J Endocrinol Metab ; 28(3): 254-259, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086569

RESUMO

Introduction: Sheehan syndrome (SS) typically involves the loss of anterior pituitary cells and rarely affects the posterior pituitary. The water deprivation test (WDT) is the gold standard for diagnosing central diabetes insipidus (CDI), but it is cumbersome. Serum copeptin measurements are an alternative for CDI diagnosis. In this study, we measured hypoglycaemia-stimulated serum copeptin in SS patients to assess posterior pituitary function alongside anterior pituitary hormone levels. Methods: This study recruited 43 patients with SS on stable hormonal replacement except for growth hormone (GH), 18 patients with CDI, and 19 body mass index (BMI) and parity-matched controls. All patients with SS and four patients with CDI underwent an insulin tolerance test (ITT), and hypoglycaemia-stimulated copeptin levels were measured at 0, 30, 45, and 90 minutes after insulin injection. Results: The mean serum copeptin level among patients with SS (26.01 ± 12.41 pmol/L) was significantly lower than that in healthy controls (31.92 ± 7.85 pmol/L) and higher than that in patients with CDI (1.81 ± 0.14 pmol/L). Using pre-defined cut-offs for CDI, basal serum copeptin <2.69 pmol/L and stimulated levels <4.92 pmol/L for complete central DI, and basal copeptin levels >2.69 pmol/L and stimulated copeptin <4.92 pmol/L for partial central DI, 9.2% (n = 4) of patients with SS had CDI, of which half had complete CDI and half had partial CDI. Conclusion: A significant number of patients with SS who are on hormone replacement therapy show involvement of the posterior pituitary, despite not displaying symptoms.

5.
Oxf Med Case Reports ; 2024(7): omae079, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39087091

RESUMO

BACKGROUND: Epidermolysis Bullosa (EB) stands as the prototype category of disorders featuring subepidermal fragility, characterized by skin blistering induced by minimal trauma. The gastrointestinal tract is a common site of extracutaneous injury. Esophageal stricture (ES) is one of the severe complications, with nearly 70% of patients experiencing ES within the initial 25 years of life. CASE REPORT: We present a 11-year-old female child of dystrophic EB (DEB) who presented with dysphagia. Barium swallow showed a short segment proximal ES. We faced many challenges before endoscopy owing to difficult intravenous access, restricted mouth opening, multiple dental caries and low haemoglobin. Dental extraction under general anaesthesia and fibreoptic intubation with a smaller sized endotracheal tube guided over epidural catheter was done at another tertiary care institute. Child had severe bleeding due to airway manipulation. MANAGEMENT: At our centre endoscopy guided serial balloon dilation (BD) of ES was performed without intubation under total intravenous anaesthesia (TIVA) without any complications. The stricture was serially dilated under direct visualization till 12 mm in three sessions at three-weekly intervals using CRE (controlled radial expansion) fixed and wire-guided balloon dilators. During the first session 20 mg of triamcinolone acetate injection was also topically applied without mucosal invasion. No such further topical or submucosal applications were attempted due to risk of perforation. CONCLUSION: Endoscopy guided BD of ES is safe and effective in EB patients when done by experienced team.

7.
Clin Imaging ; 113: 110240, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39088933

RESUMO

RATIONALE AND OBJECTIVES: Many barriers to breastfeeding upon return to the workplace are reported by female radiologists, which have implications on maternal/infant health and physician burnout. The Department of Radiology at our institution piloted an initiative to provide a free portable breast pump to address these barriers. MATERIALS AND METHODS: An anonymous voluntary 32-question survey assessing the impact of the portable pump on postpartum work-life integration was sent to all female radiologists and radiologists-in-training in the department from May 2023 to July 2023. RESULTS: A total of 59 surveys were completed (65 % response rate). Overall, respondents reported a positive or very positive impact of the pump on transitioning back to work (median 4.5/5 on a 5-point Likert scale), on their decision to continue breastfeeding when returning to work (median 4/5), and duration of breastfeeding (median 4/5). Use of the pump was reported as favorable, with utilization of the pump while simultaneously engaging in clinical work (median 4.5/5) obviating necessity of dedicated lactation rooms, and positive impact on daily productivity (median score of 4/5). Nearly all (94 %, 16/17) users of the portable pump had their lactational needs addressed while returning to work, compared to 54 % (6/13) of those returning from leave prior to the pump initiative (p = 0.003). Compared to those utilizing traditional lactational resources, those who utilized the portable pump were significantly less likely to miss educational opportunities (0 % vs 44 %, p = 0.03), or academic engagements due to lactational practices at work (0 % v 44 %, p = 0.01). CONCLUSION: A department-sponsored portable breast pump initiative proved to be an effective resource to support physician breastfeeding and work-life integration.

8.
Stem Cell Res ; 80: 103509, 2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39089181

RESUMO

Patients born with complex congenital heart defects, not amenable for surgical repair establishing normal bi-ventricular circulation are palliated with the Fontan Circulation (FC). Here, we report new iPSC line from a patient with tricuspid and pulmonary atresia. The patient underwent series of surgeries leading to completion of Fontan circulation at the age of 13yr., and this line was generated when she was 38yr. old. The exact genetic cause of this patient's congenital heart defect is unknown, and this line will be used for studying molecular and cellular mechanisms responsible for cardiac dysfunction, along with screening for future potential therapeutic avenues.

9.
Clin Psychol Psychother ; 31(4): e3033, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39089290

RESUMO

Cognitive behaviour therapy for psychosis (CBTp) should be offered to patients receiving psychiatric inpatient care, yet very little is known about patients' perspectives on this. The aim of this study was to examine patients' experiences of a CBTp-informed intervention delivered in inpatient settings. We recruited 10 participants from the intervention arm of a randomised controlled trial examining the feasibility and acceptability of a CBTp-informed intervention for psychiatric inpatient settings. We undertook semistructured interviews examining their experiences of the intervention and analysed them using thematic analysis. The study was conducted in partnership with a coproduction group of key stakeholders (people with lived experience, family and carers, and clinicians). The intervention was found helpful by almost all participants, and all participants would recommend it to others in similar situations to themselves. The results demonstrated that participants valued the therapist's professionalism and emphasised the importance of the therapeutic relationship. Participants highlighted the importance of the therapy focusing on navigating admission and developing skills to manage the crisis experience so they could return to their normal lives. Participants described challenges to having psychological therapy in the acute crisis context including therapy interruptions and ongoing distressing experiences of psychosis. The study demonstrated the importance of prioritising the therapeutic relationship, that therapy was a valued process to navigate admission and discharge, but that some environmental and patient-level challenges were present. Further research is needed to explore inpatients' experiences of psychological interventions in this setting. TRIAL REGISTRATION: ISRCTN trial registry: ISRCTN59055607.


Assuntos
Terapia Cognitivo-Comportamental , Intervenção em Crise , Pacientes Internados , Transtornos Psicóticos , Pesquisa Qualitativa , Humanos , Transtornos Psicóticos/terapia , Transtornos Psicóticos/psicologia , Feminino , Masculino , Terapia Cognitivo-Comportamental/métodos , Adulto , Intervenção em Crise/métodos , Pessoa de Meia-Idade , Pacientes Internados/psicologia , Satisfação do Paciente/estatística & dados numéricos
10.
Am J Ophthalmol ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39089358

RESUMO

PURPOSE: The purpose of this study is to compare efficacies and safeties of combined phacoemulsification-Micro-Invasive Glaucoma Surgeries (MIGS) to phacoemulsification only in eyes with open angle glaucoma. DESIGN: Systematic Review and Meta-Analysis. METHODS: A multi-database literature search was conducted to caputre MIGS articles published prior to April 19th, 2024. Key exclusion criteria were inadequate follow-up, significant loss to follow-up, standalone MIGS surgery, or primary outcomes unreported. MIGS were grouped according to mechanisms of action: 1) Trabecular Meshwork (TM) bypass which improve aqueous drainage into Schlemm's canal (SC), 2) non-GATT Goniotomies which remove TM with varying devices, and 3) GATT which remove TM with a catheter or suture placed into SC. Efficacy was measured by reductions in IOP and medications while safety was compared using incidence of sight-threatening and other adverse events. RESULTS: A total of 95 studies were included, accounting for 9733 eyes followed up at 1-year. The control group had a baseline IOP of 16.9(95%CI 15.9-17.9) mmHg on 1.43(1.19-1.68) medications and a postoperative IOP of 15.2(14.4-15.9) mmHg on 0.80(0.54-1.00) medications. The TM bypass baseline IOP was 18.2(17.6-18.7) mmHg on 1.89(1.78-2.01) medications which lowered to an IOP of 14.8(14.5-15.1) mmHg on 0.80(0.65-0.95) medications at 1-year-postoperation. The non-GATT goniotomy baseline IOP was 20.0(19.2-20.8) mmHg on 2.30(2.09-2.53) medications, and at 1-year followup the IOP was 14.6(14.3-15.0) mmHg on 1.41(1.22-1.62) medications. Lastly, the GATT baseline IOP of 21.8(19.5-24.1) mmHg on 2.90(2.36-3.44) medications was reduced to an IOP of 12.5(10.0-15.0) mmHg on 0.73(0.37-1.09) medications at 1-year-postoperation. All MIGS groups had equal or lower rates of sight-threatening events and secondary glaucoma surgery when compared to control. GATT had the highest hyphema rate at 27.7(13.5-44.5) % followed by non-GATT goniotomy with 15.5(7.8-25.0) %. These were both significantly higher than TM bypass and control groups, with hyphema rates of 3.5(1.6-5.9) % and 4% (only 1 study reporting hyphema rate), respectively. CONCLUSION: Based on current peer-reviewed articles, there is strong evidence that when compared to phacoemulsification alone, combined phaco-MIGS is beneficial for patients with open angle glaucoma and does not increase the incidence of vision-threatening events. Key limitations of our review stem from heterogeneities in protocol design or outcome reporting, and a limited number of high-quality studies with long-term follow-up.

11.
Vascul Pharmacol ; : 107414, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39089528

RESUMO

Sepsis and atherosclerotic cardiovascular disease (ASCVD) are major health challenges involving complex processes like inflammation, renin-angiotensin system (RAS) dysregulation, and thrombosis. Despite distinct clinical symptoms, both conditions share mechanisms mediated by bradykinin. This review explores bradykinin's role in inflammation, RAS modulation, and thrombosis in sepsis and ASCVD. In sepsis, variable kininogen-bradykinin levels may correlate with disease severity and progression, though the effect of bradykinin receptor modulation on inflammation remains uncertain. RAS activation is present in both diseases, with sepsis showing variable or low levels of Ang II, ACE, and ACE2, while ASCVD consistently exhibits elevated levels. Bradykinin may act as a mediator for ACE2 and AT2 receptor effects in RAS regulation. It may influence clotting and fibrinolysis in sepsis-associated coagulopathy, but evidence for an antithrombotic effect in ASCVD is insufficient. Understanding bradykinin's role in these shared pathologies could guide therapeutic and monitoring strategies and inform future research.

14.
Artigo em Inglês | MEDLINE | ID: mdl-39090454

RESUMO

Given China's prohibition on the utilization of antibiotics as feed additives in 2020, we aim to investigate nutrition additives that are both efficient and safe. Lactobacillus, a well-recognized beneficial probiotic, has explicitly been investigated for its effects on health status of the host and overall impact on food industry. To evaluate effects of Lactobacillus plantarum (LW) supplementation on broiler chicken, we conducted comprehensive multi-omics analysis, growth performance evaluation, RT-qPCR analysis, and immunofluorescence. The findings revealed that LW supplementation resulted in a substantial progress in growth performance (approximately 205 g increase in final body weight in comparison to the control group (p < 0.01)). Additionally, LW exhibited promising potential for enhancing antioxidant properties of serum and promoting gut integrity and growth as evidenced by improved antioxidant indices (p < 0.01), intestinal villus morphology (p < 0.01), and enhanced gut barrier function (p < 0.01). Meanwhile, the multi-omics analysis, including 16S rRNA sequencing and liquid chromatography-tandem mass spectrometry, revealed an enrichment of beneficial microbes in the gut of broilers that were supplemented with LW, while simultaneously depleting harmful microorganisms. Moreover, a noteworthy modification was observed in gut metabolic profiling subsequent to the execution of the probiotic strategy. Specifically, variations were noticed in the levels of metabolites and metabolic pathways such as parathyroid hormone synthesis, inflammatory mediator regulation of TRP channels, oxidative phosphorylation, and mineral absorption. Taken together, our findings validate that LW administration produces valuable effects on the health and growth performance of broilers owing to its capability to boost the gut microbiota homeostasis and intestinal metabolism. Present findings signify the potential of LW as a dietary additive to promote growth and development in broiler chickens.

15.
Opt Lett ; 49(15): 4230-4233, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090901

RESUMO

We have developed a mid-infrared Doppler-free saturation absorption spectroscopy apparatus that employs a commercial continuous-wave optical parametric oscillator (CW OPO), complemented by a home-built automation and wavelength scanning system. Here, we report a comprehensive spectral scan of the Q branch transitions of the ν3 = 1 band of methane (CH4) with an average linewidth (FWHM) of 4.5 MHz. The absolute frequency calibration was achieved using previously reported transition frequencies determined using optical frequency combs, while a Fabry-Perot etalon was used for the relative frequency calibration. We report 15 transitions with improved accuracies of 1.13 MHz (3.76 × 10-5 cm-1).

16.
Opt Lett ; 49(15): 4254-4257, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090907

RESUMO

Field enhancement of applied electric field is the foundation for the variety of applied domains at a nanoscale level. Traditionally, efforts to achieve field enhancement have required the use of complicated metamaterial-based structures with a transition behavior. Here, the electromagnetic field solution of the TM-polarized wave that interacts with an optical-axis-driven hyperbolic medium with a transition behavior is established. Detailed calculations reveal that such field enhancement can be achieved over a broad range of incident angles (i.e., near critical angle). Definitely, such flexibility of the incident angle for achieving the field enhancement enriches the understanding and provides novel prospective toward its practical realization.

17.
Am J Case Rep ; 25: e944102, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39090990

RESUMO

BACKGROUND Coccidioidomycosis is caused by the fungi Coccidioides immitis and Coccidioides posadasii, which are endemic to the southwestern United States and other countries of the Western Hemisphere. Pulmonary coccidioidomycosis is the most common form of coccidioidomycosis. Rarely, coccidioidal infection disseminates to meninges, bones, skin, and soft tissues. While fluconazole remains the first line of treatment and is used for most patients, voriconazole is used in selected refractory cases of coccidioidomycosis. Voriconazole has more fluorine molecules than other azoles, and over time the fluorine molecules in voriconazole can cause disorganized bone formation in the periosteal region (periostitis), causing generalized bony pain, and radiographically can mimic skeletal coccidioidomycosis. While voriconazole-induced periostitis has been noted in aspergillosis and other infections, it has not been reported commonly in patients with coccidioidomycosis. CASE REPORT We present a case of a 50-year-old female patient with a diagnosis coccidioidal meningitis who was refractory to fluconazole and was treated with voriconazole. She presented with bony pain, which was initially radiographically attributed to multifocal skeletal coccidioidal infection. Reflecting upon the patient's history and serum levels of fluoride and bone alkaline phosphatase, a diagnosis of voriconazole-induced periostitis was made. Discontinuation of the voriconazole resulted in resolution of the periostitis. CONCLUSIONS Voriconazole-induced periostitis should be considered in patients with musculoskeletal pain with a history of voriconazole treatment or with laboratory abnormalities, such as elevated fluoride levels and/or bone alkaline phosphatase. Discontinuation of voriconazole reverses the condition promptly.


Assuntos
Antifúngicos , Coccidioidomicose , Periostite , Voriconazol , Humanos , Periostite/induzido quimicamente , Coccidioidomicose/tratamento farmacológico , Coccidioidomicose/diagnóstico , Voriconazol/efeitos adversos , Pessoa de Meia-Idade , Feminino , Antifúngicos/efeitos adversos , Diagnóstico Diferencial
18.
J Oncol Pharm Pract ; : 10781552241265280, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39091073

RESUMO

INTRODUCTION: The treatment of cancer is associated with high risk for toxicity and high cost. Strategies to enhance the value, quality, and safety of cancer care are often managed independently of one another. Oncology stewardship is a potential framework to unify these efforts and enhance outcomes. This landscape survey establishes baseline information on oncology stewardship in the United States. METHODS: The Hematology/Oncology Pharmacy Association (HOPA) distributed a 38-item survey composed of demographic, institutional, clinical decision-making, support staff, metrics, and technology sections to 675 HOPA members between 9 September 2022 and 9 October 2022. RESULTS: Most organizations (78%) have adopted general pharmacy stewardship practices; however, only 31% reported having established a formalized oncology stewardship team. More than 70% of respondents reported implementation of biosimilars, formulary management, and dose rounding as oncology stewardship initiatives in both inpatient and outpatient settings. Frequently cited barriers to oncology stewardship included lack of clinical pharmacist availability (74%), lack of oncology stewardship training (62%), lack of physician/provider buy-in (32%), and lack of cost-saving metrics (33%). Only 6.6% of survey respondents reported their organization had defined "value in oncology." Lack of a formalized stewardship program was most often cited (77%) as the rationale for not defining value. CONCLUSIONS: Less than one-third of respondents have established oncology stewardship programs; however, most are providing oncology stewardship practices. This manuscript serves as a call to action for stakeholders to work together to formalize oncology stewardship programs that optimize value, quality, and safety for patients with cancer.

19.
bioRxiv ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39091782

RESUMO

While the proliferation of data-driven omics technologies has continued to accelerate, methods of identifying relationships among large-scale changes from omics experiments have stagnated. It is therefore imperative to develop methods that can identify key mechanisms among one or more omics experiments in order to advance biological discovery. To solve this problem, here we describe the network-based algorithm MENTOR - Multiplex Embedding of Networks for Team-Based Omics Research. We demonstrate MENTOR's utility as a supervised learning approach to successfully partition a gene set containing multiple ontological functions into their respective functions. Subsequently, we used MENTOR as an unsupervised learning approach to identify important biological functions pertaining to the host genetic architectures in Populus trichocarpa associated with microbial abundance of multiple taxa. Moreover, as open source software designed with scientific teams in mind, we demonstrate the ability to use the output of MENTOR to facilitate distributed interpretation of omics experiments.

20.
bioRxiv ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39091798

RESUMO

Multi-domain enzymes can be regulated by both inter-domain interactions and structural features intrinsic to the catalytic domain. The tyrosine phosphatase SHP2 is a quintessential example of a multi-domain protein that is regulated by inter-domain interactions. This enzyme has a protein tyrosine phosphatase (PTP) domain and two phosphotyrosine-recognition domains (N-SH2 and C-SH2) that regulate phosphatase activity through autoinhibitory interactions. SHP2 is canonically activated by phosphoprotein binding to the SH2 domains, which causes large inter-domain rearrangements, but autoinhibition can also be disrupted by disease-associated mutations. Many details of the SHP2 activation mechanism are still unclear, the physiologically-relevant active conformations remain elusive, and hundreds of human variants of SHP2 have not been functionally characterized. Here, we perform deep mutational scanning on both full-length SHP2 and its isolated PTP domain to examine mutational effects on inter-domain regulation and catalytic activity. Our experiments provide a comprehensive map of SHP2 mutational sensitivity, both in the presence and absence of inter-domain regulation. Coupled with molecular dynamics simulations, our investigation reveals novel structural features that govern the stability of the autoinhibited and active states of SHP2. Our analysis also identifies key residues beyond the SHP2 active site that control PTP domain dynamics and intrinsic catalytic activity. This work expands our understanding of SHP2 regulation and provides new insights into SHP2 pathogenicity.

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