Mesenchymal stromal cell therapy (REGENACIP®), a promising treatment option in chronic limb threatening ischemia - a narrative review.

Chronic Limb Threatening Ischemia (CLTI) is a challenging clinical problem associated with high morbidity and mortality. Endovascular interventions have been the cornerstone of treatment whenever possible. It is estimated that CLTI represents < 10% of all Peripheral Artery Disease patients, yet 50% of the patients end up either with a major amputation of the lower limbs or die of cardiovascular causes within one year period, especially in those with unsuccessful revascularization or "no-option" CLTI. Cell-based therapeutics, especially bone marrow-derived mesenchymal stromal cells have emerged as a potential, promising, and novel alternate therapeutic modality in the management of CLTI, bolstered with positive results in numerous research, including randomized and nonrandomized trials. REGENACIP® is one such BM-MSC therapy approved by Central Drugs Standard Control Organization in India for the management of "no-option" Atherosclerotic Peripheral Arterial disease / Buerger's disease patients with established critical limb ischemia in Rutherford Grade III-5 or III-6, not eligible for or have failed traditional revascularization treatment, with rest pain and / or ulcers in the affected limb. The current review aims to deliberate upon the various aspects of CLTI and clinical benefits of REGENACIP® therein.

Activating pyruvate kinase improves red blood cell integrity by reducing band 3 tyrosine phosphorylation.

In a Phase 1 study (NCT04000165), we established proof-of-concept for activating pyruvate kinase (PK) in sickle cell disease (SCD) as a viable anti-sickling therapy. AG-348 (mitapivat), a PK activator, increased adenosine triphosphate (ATP) and decreased 2,3- diphosphoglycerate levels while patients were on treatment in line with the mechanism of the drug. We noted that the increased hemoglobin persisted for 4 weeks after stopping AG-348 until the end of study (EOS). Here, we investigated the pathways modulated by activating PK that may contribute to the improved red blood cell (RBC) survival after AG-348 cessation. We evaluated frozen whole blood samples taken at multiple timepoints from the patients in the Phase 1 study, from which RBC ghosts were isolated and analyzed by Western blotting for tyrosine-phosphorylation of band 3 (Tyr-p-bd3), ankyrin-1 and intact (active) protein tyrosine phosphatase 1B (PTP1B) levels. We observed a significant dose-dependent decrease in mean Tyr-p-bd3 from baseline in the subjects, accompanied by increase in levels of membrane-associated ankyrin-1 and intact PTP1B, all of which returned to near baseline by EOS. As PTP1B is cleaved (inactivated) by intracellular Ca2+-dependent calpain, we next measured the effect of AG-348 on ATP production and calpain activity, and the plasma membrane Ca2+ ATPase pump (PMCA)-mediated efflux kinetics in HbAA and HbSS erythrocytes. AG-348 treatment increased ATP levels, decreased calpain activity, and increased Ca2+ efflux. Altogether, our data indicate that ATP increase is a key mechanism underlying the increase in hemoglobin levels upon PK activation in SCD.

Plasmodium falciparum CLAG Paralogs All Traffic to the Host Membrane but Knockouts Have Distinct Phenotypes.

Malaria parasites increase their host erythrocyte's permeability to obtain essential nutrients from plasma and facilitate intracellular growth. In the human Plasmodium falciparum pathogen, this increase is mediated by the plasmodial surface anion channel (PSAC) and has been linked to CLAG3, a protein integral to the host erythrocyte membrane and encoded by a member of the conserved clag multigene family. Whether paralogs encoded by other clag genes also insert at the host membrane is unknown; their contributions to PSAC formation and other roles served are also unexplored. Here, we generated transfectant lines carrying epitope-tagged versions of each CLAG. Each paralog is colocalized with CLAG3, with concordant trafficking via merozoite rhoptries to the host erythrocyte membrane of newly invaded erythrocytes. Each also exists within infected cells in at least two forms: an alkaline-extractable soluble form and a form integral to the host membrane. Like CLAG3, CLAG2 has a variant region cleaved by extracellular proteases, but CLAG8 and CLAG9 are protease resistant. Paralog knockout lines, generated through CRISPR/Cas9 transfection, exhibited uncompromised growth in PGIM, a modified medium with higher physiological nutrient levels; this finding is in marked contrast to a recently reported CLAG3 knockout parasite. CLAG2 and CLAG8 knockout lines exhibited compensatory increases in the transcription of the remaining clags and associated rhoph genes, yielding increased PSAC-mediated uptake for specific solutes. We also report on the distinct transport properties of these knockout lines. Similar membrane topologies at the host membrane are consistent with each CLAG paralog contributing to PSAC, but other roles require further examination.

Optimized plasmid loading of human erythrocytes for Plasmodium falciparum DNA transfections.

In vitro modification of Plasmodium falciparum genes is the cornerstone of basic and translational malaria research. Achieved through DNA transfection, these modifications may entail altering protein sequence or abundance. Such experiments are critical for defining the molecular mechanisms of key parasite phenotypes and for validation of drug and vaccine targets. Despite its importance, successful transfection remains difficult and is a resource-intensive, rate-limiting step in P. falciparum research. Here, we report that inefficient loading of plasmid into erythrocytes limits transfection efficacy with commonly used electroporation methods. As these methods also require expensive instrumentation and consumables that are not broadly available, we explored a simpler method based on plasmid loading through hypotonic lysis and resealing of erythrocytes. We used parasite expression of a sensitive NanoLuc reporter for rapid evaluation and optimization of each step. Hypotonic buffer composition, resealing buffer volume and composition, and subsequent incubation affected plasmid retention and successful transfection. While ATP was critical for erythrocyte resealing, addition of Ca++ or glutathione did not improve transfection efficiency, with increasing Ca++ concentrations proving detrimental to outcomes. Compared with either the standard electroporation method or a previously reported hypotonic loading protocol, the optimized method yields greater plasmid loading and higher expression of the NanoLuc reporter 48 h after transfection. It also produced significantly faster outgrowth of parasites in transfections utilizing either episomal expression or CRISPR-Cas9 mediated integration. This new method produces higher P. falciparum transfection efficiency, reduces resource requirements and should accelerate molecular studies of malaria drug and vaccine targets.

Novel Ion Channel Genes in Malaria Parasites.

Ion channels serve many cellular functions including ion homeostasis, volume regulation, signaling, nutrient acquisition, and developmental progression. Although the complex life cycles of malaria parasites necessitate ion and solute flux across membranes, the whole-genome sequencing of the human pathogen Plasmodium falciparum revealed remarkably few orthologs of known ion channel genes. Contrasting with this, biochemical studies have implicated the channel-mediated flux of ions and nutritive solutes across several membranes in infected erythrocytes. Here, I review advances in the cellular and molecular biology of ion channels in malaria parasites. These studies have implicated novel parasite genes in the formation of at least two ion channels, with additional ion channels likely present in various membranes and parasite stages. Computational approaches that rely on homology to known channel genes from higher organisms will not be very helpful in identifying the molecular determinants of these activities. Given their unusual properties, novel molecular and structural features, and essential roles in pathogen survival and development, parasite channels should be promising targets for therapy development.

Precision Education: The Future of Lifelong Learning in Medicine.

ABSTRACT: The goal of medical education is to produce a physician workforce capable of delivering high-quality equitable care to diverse patient populations and communities. To achieve this aim amidst explosive growth in medical knowledge and increasingly complex medical care, a system of personalized and continuous learning, assessment, and feedback for trainees and practicing physicians is urgently needed. In this perspective, the authors build on prior work to advance a conceptual framework for such a system: precision education (PE).PE is a system that uses data and technology to transform lifelong learning by improving personalization, efficiency, and agency at the individual, program, and organization levels. PE "cycles" start with data inputs proactively gathered from new and existing sources, including assessments, educational activities, electronic medical records, patient care outcomes, and clinical practice patterns. Through technology-enabled analytics , insights are generated to drive precision interventions . At the individual level, such interventions include personalized just-in-time educational programming. Coaching is essential to provide feedback and increase learner participation and personalization. Outcomes are measured using assessment and evaluation of interventions at the individual, program, and organizational levels, with ongoing adjustment for repeated cycles of improvement. PE is rooted in patient, health system, and population data; promotes value-based care and health equity; and generates an adaptive learning culture.The authors suggest fundamental principles for PE, including promoting equity in structures and processes, learner agency, and integration with workflow (harmonization). Finally, the authors explore the immediate need to develop consensus-driven standards: rules of engagement between people, products, and entities that interact in these systems to ensure interoperability, data sharing, replicability, and scale of PE innovations.

Antiplasmodial peptaibols act through membrane directed mechanisms.

Our previous study identified 52 antiplasmodial peptaibols isolated from fungi. To understand their antiplasmodial mechanism of action, we conducted phenotypic assays, assessed the in vitro evolution of resistance, and performed a transcriptome analysis of the most potent peptaibol, HZ NPDG-I. HZ NPDG-I and 2 additional peptaibols were compared for their killing action and stage dependency, each showing a loss of digestive vacuole (DV) content via ultrastructural analysis. HZ NPDG-I demonstrated a stepwise increase in DV pH, impaired DV membrane permeability, and the ability to form ion channels upon reconstitution in planar membranes. This compound showed no signs of cross resistance to targets of current clinical candidates, and 3 independent lines evolved to resist HZ NPDG-I acquired nonsynonymous changes in the P. falciparum multidrug resistance transporter, pfmdr1. Conditional knockdown of PfMDR1 showed varying effects to other peptaibol analogs, suggesting differing sensitivity.

Navigating the Landscape of Precision Education: Insights From On-the-Ground Initiatives.

ABSTRACT: A central goal of precision education (PE) is efficiently delivering the right educational intervention to the right learner at the right time. This can be achieved through a PE cycle that involves gathering inputs, using analytics to generate insights, planning and implementing interventions, learning and assessing outcomes, and then using lessons learned to inform modifications to the cycle. In this paper, the authors describe 3 PE initiatives utilizing this cycle. The Graduate Medical Education Laboratory (GEL) uses longitudinal data on graduate trainee behavior, clinical skills, and wellness to improve clinical performance and professional fulfillment. The Transition to Residency Advantage (TRA) program uses learner data from medical school coupled with individualized coaching to improve the transition to residency. The Anesthesia Research Group for Educational Technology (TARGET) is developing an automated tool to deliver individualized education to anesthesia residents based on a longitudinal digital representation of the learner. The authors discuss strengths of the PE cycle and transferrable learnings for future PE innovations. Common challenges are identified, including related to data (e.g., volume, variety, sharing across institutions, using the electronic health record), analytics (e.g., validating augmented intelligence models), and interventions (e.g., scaling up learner assessments with limited resources). PE developers need to share their experiences in order to overcome these challenges, develop best practices, and ensure ethical development of future systems. Adapting a common framework to develop and assess PE initiatives will lead to a clearer understanding of their impact, help to mitigate potential risks, and allow deployment of successful practices on a larger scale.

NK cell-induced damage to P.falciparum-infected erythrocytes requires ligand-specific recognition and releases parasitophorous vacuoles that are phagocytosed by monocytes in the presence of immune IgG.

Natural killer (NK) cells lyse virus-infected cells and transformed cells through polarized delivery of lytic effector molecules into target cells. We have shown that NK cells lyse Plasmodium falciparum-infected red blood cells (iRBC) via antibody-dependent cellular cytotoxicity (ADCC). A high frequency of adaptive NK cells, with elevated intrinsic ADCC activity, in people chronically exposed to malaria transmission is associated with reduced parasitemia and resistance to disease. How NK cells bind to iRBC and the outcome of iRBC lysis by NK cells has not been investigated. We applied gene ablation in inducible erythrocyte precursors and antibody-blocking experiments with iRBC to demonstrate a central role of CD58 and ICAM-4 as ligands for adhesion by NK cells via CD2 and integrin αMß2, respectively. Adhesion was dependent on opsonization of iRBC by IgG. Live imaging and quantitative flow cytometry of NK-mediated ADCC toward iRBC revealed that damage to the iRBC plasma membrane preceded damage to P. falciparum within parasitophorous vacuoles (PV). PV were identified and tracked with a P.falciparum strain that expresses the PV membrane-associated protein EXP2 tagged with GFP. After NK-mediated ADCC, PV were either found inside iRBC ghosts or released intact and devoid of RBC plasma membrane. Electron microscopy images of ADCC cultures revealed tight NK-iRBC synapses and free vesicles similar in size to GFP+ PV isolated from iRBC lysates by cell sorting. The titer of IgG in plasma of malaria-exposed individuals that bound PV was two orders of magnitude higher than IgG that bound iRBC. This immune IgG stimulated efficient phagocytosis of PV by primary monocytes. The selective NK-mediated damage to iRBC, resulting in release of PV, and subsequent phagocytosis of PV by monocytes may combine for efficient killing and removal of intra-erythrocytic P.falciparum parasite. This mechanism may mitigate the inflammation and malaria symptoms during blood-stage P. falciparum infection.

Diagnostic criteria for Buerger's disease: International Consensus of VAS - European Independent Foundation in Angiology/Vascular Medicine.

Buerger's disease (BD) remains a debilitating condition and early diagnosis is paramount for its effective management. Despite many published diagnostic criteria for BD, selective criteria have been utilized in different vascular centers to manage patients with BD worldwide. A recent international Delphi Consensus Study on the diagnostic criteria of BD showed that none of these published diagnostic criteria have been universally accepted as a gold standard. Apart from the presence of smoking, these published diagnostic criteria have distinct differences between them, rendering the direct comparison of patient outcomes difficult. Hence, the expert committees from the Working Group of the VAS-European Independent Foundation in Angiology/Vascular Medicine critically reviewed the findings from the Delphi study and provided practical recommendations on the diagnostic criteria for BD, facilitating its universal use. We recommend that the 'definitive' diagnosis of BD must require the presence of three features (history of smoking, typical angiographic features and typical histopathological features) and the use of a combination of major and minor criteria for the 'suspected' diagnosis of BD. The major criterion is the history of active tobacco smoking. The five minor criteria are disease onset at age less than 45 years, ischemic involvement of the lower limbs, ischemic involvement of one or both of the upper limbs, thrombophlebitis migrans and red-blue shade of purple discoloration on edematous toes or fingers. We recommend that a 'suspected' diagnosis of BD is confirmed in the presence of a major criterion plus four or more minor criteria. In the absence of the major criterion or in cases of fewer than four minor criteria, imaging and laboratory data could facilitate the diagnosis. Validation studies on the use of these major and minor criteria are underway.

Unique Properties of Nutrient Channels on Plasmodium-Infected Erythrocytes.

Intracellular malaria parasites activate an ion and organic solute channel on their host erythrocyte membrane to acquire a broad range of essential nutrients. This plasmodial surface anion channel (PSAC) facilitates the uptake of sugars, amino acids, purines, some vitamins, and organic cations, but remarkably, it must exclude the small Na+ ion to preserve infected erythrocyte osmotic stability in plasma. Although molecular, biochemical, and structural studies have provided fundamental mechanistic insights about PSAC and advanced potent inhibitors as exciting antimalarial leads, important questions remain about how nutrients and ions are transported. Here, I review PSAC's unusual selectivity and conductance properties, which should guide future research into this important microbial ion channel.

The External Jugular Vein Cut-Down Method for Chemoport Insertion from a Tertiary Cancer Treatment Center in Central India: A Prospective Study.

INTRODUCTION: In the realm of oncology, the development of TIVAD (chemoport) has been a blessing for cancer patients, freeing them from having to undergo numerous recurrent venepunctures throughout their treatment. The External Jugular Vein cut-down has been the standard procedure for administering chemotherapy to cancer patients at our institution. Here, we discuss our experience with the External Jugular Vein cut-down Chemoport Insertion Technique and the outcomes it produced. MATERIALS AND METHODS: We performed a prospective observational study and included all patients who underwent the open External Jugular Vein cut-down technique of Chemoport Insertion from January 2019 to January 2022 in the Department of Surgical Oncology at our hospital. RESULTS: Out of 136 patients, 3 (2.2%) had failed external jugular vein (EJV) cannulation, and alternative access (Internal Jugular Vein) was chosen for cannulation. The most common indication for chemoport insertion in our study was carcinoma of the breast, around 72.93% (97/133), and hence the majority of patients were females, about 84.21% (112/133). Only 18.04% (24/133) were male patients. The age distribution ranged from 2 years to 84 years. Out of 133 patients, complications were observed in 14 patients (10.52%). Around 6 patients (4.5%) had problems with catheter blockage after one cycle of chemotherapy. 4 patients (3%) had port infections at the chamber region (pectoral region). 3 patients (2.2%) had catheter tip displacement into the brachiocephalic vein. 1 patient (0.75%) had extravasation of chemotherapy. CONCLUSION: In conclusion, our study demonstrates that the External Jugular Vein cut-down technique offers several advantages in the realm of oncology, as it is a safe, efficient, and straightforward technique for chemoport insertion. With its minimal learning curve and simplicity, this technique represents a favorable initial option for successfully implanting chemoports in cancer patients. Further research and comparative studies are needed to validate and further explore the benefits of this technique in diverse patient populations and healthcare settings.

Beyond Traditional Approaches: A Pilot Study Exploring the Role of Injection Mitomycin C on the Surgical Resection Bed in Oral Cancer Treatment.

Background Oral cavity cancer ranks sixth among all cancers worldwide. India has the most oral cancer cases and accounts for one-third of the global oral cancer burden. Oral cavity cancer is known to be associated with an elevated likelihood of locoregional recurrences, which account for the bulk of post-surgery and radiotherapy treatment failures. Mitomycin C (MMC) is an antineoplastic and antibiotic agent that is administered topically rather than intravenously to treat bladder and intraperitoneal tumors to avoid recurrences. This study aimed to investigate the use of injection MMC as a local application on surgical resection beds for patients undergoing surgery for oral cancer and to assess its efficacy in preventing regional recurrences. Methodology In this prospective, interventional, pilot study, patients were assigned randomly to two groups using simple randomization. Group A involved the application of two gauze pieces soaked with MMC injection. Group B involved the application of two gauze pieces soaked with a 10% betadine solution. During the pectoralis major myocutaneous flap harvest procedure for reconstruction, two gauze pieces soaked with either injection MMC solution (20 mg MMC in 20 mL of 0.9% normal saline) or 10% betadine solution were placed on the surgical resection bed for a 45-minute contact period. Patients were evaluated daily in the postoperative period for local complications. Regular follow-up visits were scheduled for 15 months of follow-up. Results After exclusions at various phases, the final analysis included 50 patients in Group A and 50 patients in Group B. Minor complications, specifically blackening of the skin flap in the neck resulting in surgical site infections, were observed in 16% (eight patients) of the MMC group and in 6% (three patients) of the betadine group (p = 0.1997) patients. In the MMC group, two (4%) patients experienced locoregional recurrences at three months, four (8%) patients at six months, six (12%) patients at nine months, eight (16%) patients at 12 months, and 10 (20%) patients at 15 months of follow-up. In contrast, locoregional recurrences occurred in two (4%) patients in the betadine group at three months, six (12%) patients at six months, nine (18%) patients at nine months, 12 (24%) patients at 12 months, and 15 (30%) patients at 15 months. Although the difference in locoregional recurrences between the two groups was not statistically significant, there was a trend of decreasing locoregional recurrences in the MMC group relative to the betadine group as the duration of follow-up increased. In the subgroup analysis of patients with pathological extranodal extension (ENE), only 10 of 18 patients with ENE in Group A (55.55%) experienced a recurrence, whereas all 12 patients with ENE in Group B (100%) experienced a recurrence within the same time frame. This difference in locoregional recurrence rates between the two groups was statistically significant, with a p-value of 0.0100. Conclusions Our study demonstrated that the local administration of MMC on surgical resection beds may lower the risk of locoregional recurrences in patients with oral cancer, especially those with ENE. These findings contribute to the ongoing efforts to enhance treatment strategies and patient outcomes for this challenging malignancy.

Using poetry to elicit internal medicine residents' perspectives on wellness.

PURPOSE: To elicit internal medicine residents' perspectives on wellness through poetry writing, examining (1) response rates, (2) the tone/sentiment of their submissions and (3) the primary thematic content. STUDY DESIGN: In academic year 2019-2020, a random sample of 88 residents from four internal medicine residency programmes was invited to participate in a year-long study of wellness. In December 2019, an open-ended prompt asked residents to write a poem reflecting on their well-being. Responses were inductively coded using content analysis techniques. RESULTS: The response rate for the poetry prompt was 94%. The tone of the entries was most often neutral or contradictory (42%), followed by negative (33%) and positive (25%). There were three main themes: (1) Mindsets: most residents simply wanted to make it through their programme; (2) wellness influencers: the main wellness supporters were external to the programme such as vacationing and exercise; within hospitals, friendships with colleagues and boosted wellness and (3) scheduling/repetition: difficult schedules drained energy as did the monotony of administrative tasks. CONCLUSIONS: Poetry appears to be an innovative and effective vehicle to elicit residents' perspectives without compromising response rate. Poetry survey techniques allow medical trainees to provide powerful messaging to leadership. Most of what is known about trainee wellness is derived from quantitative surveys. This study showed medicine trainees' willingness to engage in poetry and add richness and personal detail to highlight key drivers of wellness. Such information provides context and brings attention in a compelling manner to an important topic.

Topical Esmolol Hydrochloride as a Novel Treatment Modality for Diabetic Foot Ulcers: A Phase 3 Randomized Clinical Trial.

Importance: Preclinical and phase 1/2 studies with esmolol hydrochloride suggest its potential role in treatment of diabetic foot ulcers (DFUs). Objective: To study the efficacy of topical esmolol for healing of uninfected DFUs. Design, Setting, and Participants: A randomized, double-blind, multicenter, phase 3 clinical trial was conducted from December 26, 2018, to August 19, 2020, at 27 referral centers across India. Participants included adults with DFUs. Interventions: Participants were randomized after a run-in phase (1 week) to receive esmolol, 14%, gel with standard of care (SoC), SoC only, or vehicle with SoC (3:3:1 proportion) for 12 weeks (treatment phase) and followed up subsequently until week 24. Main Outcomes and Measures: The primary outcome was the proportion of wound closure within the 12-week treatment phase in the esmolol with SoC and SoC only groups. Analysis was conducted using an intention-to-treat safety evaluable population, full analysis set or efficacy-evaluable population, and per-protocol population comparing the esmolol plus SoC and SoC only treatment groups. Results: In the study, 176 participants (122 men [69.3%]; mean [SD] age, 56.4 [9.0] years; mean [SD] hemoglobin A1c level, 8.6% [1.6%]) with DFUs classified as University of Texas Diabetic Wound Classification system grade IA and IC (mean [SD] ulcer area, 4.7 [2.9] cm2) were randomized to the 3 groups. A total of 140 participants were analyzed for efficacy. The proportion of participants in the esmolol with SoC group who achieved target ulcer closure within 12 weeks was 41 of 68 (60.3%) compared with 30 of 72 (41.7%) participants in the SoC only group (odds ratio [OR], 2.13; 95% CI, 1.08-4.17; P = .03). A total of 120 participants completed the end of study visit which were analyzed. Target ulcer closure by the end of the study (week 24) was achieved in 44 of 57 (77.2%) participants in the esmolol with SoC group and 35 of 63 (55.6%) participants in the SoC only group (OR, 2.71; 95% CI, 1.22-5.99; P = .01). The median time for ulcer closure was 85 days for the esmolol with SoC group and was not estimable for SoC only group. Significant benefits of Esmolol with SoC were seen in patients with factors that impede the healing of DFU. Treatment-emergent adverse events were noted in 18.8% of the participants, but most (87.3%) of these events were not attributable to the study drug. Conclusions and Relevance: In this multicenter, randomized, double-blind clinical trial, the addition of esmolol to SoC was shown to significantly improve the healing of DFUs. With these results, topical esmolol may be an appropriate addition to SoC for treating DFUs. Trial Registration: ClinicalTrials.gov Identifier: NCT03998436; Clinical Trial Registry, India CRI Number: CTRI/2018/11/016295.