pH-sensitive release of nitric oxide gas using peptide-graphene co-assembled hybrid nanosheets.

Nitric oxide (NO) donating drugs such as organic nitrates have been used to treat cardiovascular diseases for more than a century. These donors primarily produce NO systemically. It is however sometimes desirable to control the amount, location, and time of NO delivery. We present the design of a novel pH-sensitive NO release system that is achieved by the synthesis of dipeptide diphenylalanine (FF) and graphene oxide (GO) co-assembled hybrid nanosheets (termed as FF@GO) through weak molecular interactions. These hybrid nanosheets were characterised by using X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, zeta potential measurements, X-ray photoelectron spectroscopy, scanning and transmission electron microscopies. The weak molecular interactions, which include electrostatic, hydrogen bonding and π-π stacking, are pH sensitive due to the presence of carboxylic acid and amine functionalities on GO and the dipeptide building blocks. Herein, we demonstrate that this formulation can be loaded with NO gas with the dipeptide acting as an arresting agent to inhibit NO burst release at neutral pH; however, at acidic pH it is capable of releasing NO at the rate of up to 0.6 µM per minute, comparable to the amount of NO produced by healthy endothelium. In conclusion, the innovative conjugation of dipeptide with graphene can store and release NO gas under physiologically relevant concentrations in a pH-responsive manner. pH responsive NO-releasing organic-inorganic nanohybrids may prove useful for the treatment of cardiovascular diseases and other pathologies.

Rate and Predictors of Patient Satisfaction After Total Joint Arthroplasty: A Cross-Sectional Study in a Low-to-Middle-Income Country.

Objective This study aimed to assess the rate of patient satisfaction after primary total joint arthroplasty (TJA) using a validated satisfaction measure. Materials and methods A cross-sectional study was conducted, including all patients who underwent primary TJA between December 2021 and February 2023. The age of the study population was found to range from 23 to 86 years. Patient satisfaction was assessed using a validated tool comprising four questions and a quality of life (QoL) question. Results A total of 197 patients were included, with a mean age of 60.9 ± 12.7 years. Total knee replacement (TKR) was performed in 124 patients (62.9%), and total hip replacement (THR) in 73 patients (37.1%). The mean patient satisfaction score was 86.6 ± 14.4 out of a maximum of 100. A significant negative correlation was observed between the Charlson Comorbidity Index (CCI) and the overall satisfaction score (p-value = 0.029). The majority of the patients (52.3%, n = 103) answered that their QoL had greatly improved, and a similar level of improvement was noted in elderly vs. adult patients (p-value = 0.17). A significantly higher proportion of male patients reported improvement more than they ever expected compared to female patients, the majority of whom reported their QoL was greatly improved (p-value = 0.025). Conclusion Total joint arthroplasty has been shown to achieve good patient satisfaction and an improvement in QoL. However, an increased comorbidity index and female gender were identified as factors for reduced satisfaction. Hence, it is recommended to consider these factors and counsel patients accordingly based on local patient data.

Predictors of clinical outcomes in patients with sepsis: A retrospective study from a tertiary care hospital in Pakistan.

OBJECTIVE: To assess associations between various clinic-demographic factors and clinical outcomes among patients treated for sepsis. METHODS: The retrospective study was conducted at the Aga Khan University Hospital, Karachi, and comprised data of all patients aged >18 years diagnosed with sepsis from January to December 2019. Multivariable logistic regression was used to evaluate independent associations between predictors and outcomes. Data was analysed using R packages. RESULTS: Of the 1,136 patients, 621(54.6%) were male and 515(45.3%) were female. The overall mean age was 59.05±16.91 years. Female gender (odds ratio: 1.029; 95% confidence interval: 1.03-1.64) was found to be an independent predictor of septic shock, while hypertension (odds ratio0.75; 95% confidence interval: 0.59-0.95) emerged as a protective factor. Chronic kidney disease (odds ratio: 1.539; 95% confidence interval: 1.14-2.07) was an independent predictor of prolonged length of stay, while older age appeared to be protective (odds ratio: 0.98; 95% confidence interval: 0.98-0.99). Mortality was associated with a significantly lower odds of Escherichia coli on culture (odds ratio: 0.26; 95% confidence interval: 0.12-0.54). CONCLUSIONS: Independent associations were found between specific patient characteristics and adverse clinical outcomes.

Modified Frailty Index as a Predictor of Adverse Outcomes in Elective Primary Hip and Knee Replacement Surgery Patients at a Tertiary Care Hospital in Pakistan: A Cross-Sectional Study.

Objective The objective was to evaluate the modified frailty index as a predictor of early (within 30 days) postoperative complications in total joint arthroplasty patients, in a low middle-income country. Material and methods A cross-sectional study was carried out which included patients with ages ranging from 23 to 86 years, who underwent elective primary Total Hip or Knee Arthroplasties (TKA or THA) between December 2021 and February 2023. Modified frailty index (mFI-5) was calculated and 30-day morbidity and mortality were recorded. Post-operative complications were categorized as either surgical or medical and recorded. Results A total of 175 patients were included, amongst whom the majority were females (68.6%, n=120) and the mean age was 60.5 ± 13.2 years. 85 patients (48.6%) had a mFI-5 score of one while 48 patients (27.4%) had a score of two. Superficial surgical site infection was the most common complication overall in 6 patients (3.4%); however, no case of prosthetic joint infection was noted. Deep vein thrombosis (DVT) was the most common medical complication (1.7%, n=3). 5 patients (2.9%) required re-admission and two mortalities were recorded within the 30-day interval. A significant association was noted between post-operative surgical complications and mFI-5 score (p-value = < 0.001), with the risk of complications increasing with a higher mFI-5 score. Smoking was noted to be a risk factor for post-operative medical complications as well as 30-day mortality. Conclusion The current study shows that the mFI-5 index can effectively be used as a predictor of postoperative complications in the South Asian region such as Pakistan. This should be calculated routinely and can be used as a tool for pre-operative assessment and counseling.

Peptide-conjugated Nanoparticle Platforms for Targeted Delivery, Imaging, and Biosensing Applications.

Peptides have become an indispensable tool in engineering of multifunctional nanostructure platforms for biomedical applications such as targeted drug and gene delivery, imaging and biosensing. They can be covalently incorporated into a variety of nanoparticles (NPs) including polymers, metallic nanoparticles, and others. Using different bioconjugation techniques, multifunctional peptide-modified NPs can be formulated to produce therapeutical and diagnostic platforms offering high specificity, lower toxicity, biocompatibility, and stimuli responsive behavior. Targeting peptides can direct the nanoparticles into specific tissues for targeted drug and gene delivery and imaging applications due to their specificity towards certain receptors. Furthermore, due to their stimuli-responsive features, they can offer controlled release of therapeutics into desired sites of disease. In addition, peptide-based biosensors and imaging agents can provide non-invasive detection and monitoring of diseases including cancer, infectious diseases, and neurological disorders. In this review, we covered the design and formulation of recent peptide-based NP platforms, as well as their utilization in in vitro and in vivo applications such as targeted drug and gene delivery, targeting, sensing, and imaging applications. In the end, we provided the future outlook to design new peptide conjugated nanomaterials for biomedical applications.

FBXO8 is a novel prognostic biomarker in different molecular subtypes of breast cancer and suppresses breast cancer progression by targeting c-MYC.

F-box only protein 8 (FBXO8) is a recently identified member of the F-box proteins, showcasing its novelty in this protein family. Extensive research has established FBXO8's role as a tumor suppressor in various cancers, including hepatocellular carcinoma, and colorectal cancer, Nevertheless, its functional, mechanistic, and prognostic roles in primary and metastatic breast cancer, particularly in different molecular subtypes of breast cancer, various stages, as well as its potential implications in immunotherapy, tumor microenvironment, and prognostic survival among breast cancer patients, remain unexplored. In this article, we employed a multi-dimensional investigation leveraging TCGA, TIMER, TISIDB, STRING, MEXPRESS, UALCAN, and cBioPortal databases to explore the underlying suppression mechanism of FBXO8 in breast cancer. FBXO8 negatively correlates with MYC, NOTCH, WNT and inflammatory signaling pathways in breast tumor microenvironment. Furthermore we conducted RT-PCR, western blot, cell proliferation, cell migration, and mRNA target gene RT-PCR analyses to elucidate the role of FBXO8 in breast cancer progression. Mechanistically, PTEN and FBXW7 expression were down-regulated and MYC, IL10, IL6, NOTCH1, WNT6 mRNA expressions were up-regulated in FBXO8 knockdown cell lines. c-MYC silenced cells showed an increase in FBXO8 protein level, which suggests a negative feedback loop between FBXO8 and c-MYC to control breast cancer metastasis. These findings illuminate the novel role of FBXO8 as a prognostic and therapeutic target across different molecular subtypes of breast cancer. Finally, through the utilization of virtual screening and Molecular Dynamics simulations, we successfully identified two FDA-approved medications, Ledipasvir and Paritaprevir, that demonstrated robust binding capabilities and interactions with FBXO8.

Machine and Deep Learning: Artificial Intelligence Application in Biotic and Abiotic Stress Management in Plants.

Biotic and abiotic stresses significantly affect plant fitness, resulting in a serious loss in food production. Biotic and abiotic stresses predominantly affect metabolite biosynthesis, gene and protein expression, and genome variations. However, light doses of stress result in the production of positive attributes in crops, like tolerance to stress and biosynthesis of metabolites, called hormesis. Advancement in artificial intelligence (AI) has enabled the development of high-throughput gadgets such as high-resolution imagery sensors and robotic aerial vehicles, i.e., satellites and unmanned aerial vehicles (UAV), to overcome biotic and abiotic stresses. These High throughput (HTP) gadgets produce accurate but big amounts of data. Significant datasets such as transportable array for remotely sensed agriculture and phenotyping reference platform (TERRA-REF) have been developed to forecast abiotic stresses and early detection of biotic stresses. For accurately measuring the model plant stress, tools like Deep Learning (DL) and Machine Learning (ML) have enabled early detection of desirable traits in a large population of breeding material and mitigate plant stresses. In this review, advanced applications of ML and DL in plant biotic and abiotic stress management have been summarized.

Intrapulmonary schwannoma presenting as an asymptomatic lung mass: a case report.

BACKGROUND: Schwannomas are solitary well-circumscribed encapsulated benign tumors that exhibit Schwann cell differentiation, and arise directly from myelinated peripheral or central nerves. Although they are usually asymptomatic and found incidentally, schwannomas can cause symptoms due to compression of nearby structures which, depending on the location, can make clinical presentations widely variable. Despite their rarity, schwannomas have been documented in a number of locations including the limbs, cerebellopontine angle, posterior mediastinum, and, far more infrequently, the lungs. CASE PRESENTATION: In this article, we report an incidental finding of an intrapulmonary schwannoma in a 59-year-old Pakistani woman who was grossly asymptomatic upon presentation to the cardiothoracic surgery clinic. An [18F]fluorodeoxyglucose positron emission tomography/computed tomography scan revealed a lobulated soft-tissue lesion measuring 23 mm × 23 mm in the lower lobe of the right lung. A computed tomography-guided core biopsy of the mass was performed, which revealed a benign spindle cell lesion based on histopathological examination and immunohistochemical staining. The mass was surgically resected via a right lower lobectomy, and subsequently confirmed to be an encapsulated neoplastic lesion composed of well-differentiated Schwann cells. There were no short- or long-term complications, morbidities, or recurrences based on 1-year follow-up. CONCLUSION: This report underscores the predominantly asymptomatic nature of schwannomas and reemphasizes the efficacy of surgical resection as a safe and curative procedure for a tumor of this nature. Albeit very rare, intrapulmonary schwannomas can be considered a differential diagnosis when encountering solitary asymptomatic pulmonary nodules or masses.

Selective amide bond formation in redox-active coacervate protocells.

Coacervate droplets are promising protocell models because they sequester a wide range of guest molecules and may catalyze their conversion. However, it remains unclear how life's building blocks, including peptides, could be synthesized from primitive precursor molecules inside such protocells. Here, we develop a redox-active protocell model formed by phase separation of prebiotically relevant ferricyanide (Fe(CN)63-) molecules and cationic peptides. Their assembly into coacervates can be regulated by redox chemistry and the coacervates act as oxidizing hubs for sequestered metabolites, like NAD(P)H and gluthathione. Interestingly, the oxidizing potential of Fe(CN)63- inside coacervates can be harnessed to drive the formation of new amide bonds between prebiotically relevant amino acids and α-amidothioacids. Aminoacylation is enhanced in Fe(CN)63-/peptide coacervates and selective for amino acids that interact less strongly with the coacervates. We finally use Fe(CN)63--containing coacervates to spatially control assembly of fibrous networks inside and at the surface of coacervate protocells. These results provide an important step towards the prebiotically relevant integration of redox chemistry in primitive cell-like compartments.

Comparative analysis of endophytic fungal communities in bamboo species Phyllostachys edulis, Bambusa rigida, and Pleioblastus amarus.

Fungal endophytes in plant leaf mesophyll form mutually beneficial associations through carbon assimilation, synthesis of biologically active chemicals, and enhancement of aesthetic and nutritional value. Here, we compared community structure, diversity, and richness of endophytic fungi in the leaves of three bamboo species, including Phyllostachys edulis (MZ), Bambusa rigida (KZ), and Pleioblastus amarus (YT) via high-throughput Illumina sequencing. In total, 1070 operational taxonomic units (OTUs) were retrieved and classified into 7 phylum, 27 classes, 82 orders, 185 families, 310 genus, and 448 species. Dominant genera were Cladosporium, Trichomerium, Hannaella, Ascomycota, Sporobolomyces, Camptophora and Strelitziana. The highest fungal diversity was observed in Pleioblastus amarus, followed by Bambusa rigida, and Phyllostachys edulis. Comparatively, monopodial species Ph. edulis and sympodial B. rigida, mixed P. amarus revealed the highest richness of endophytic fungi. We retrieved a few biocontrol agents, Sarocladium and Paraconiothyrium, and unique Sporobolomyces, Camptophora, and Strelitziana genera. FUNGuild analysis revealed the surrounding environment (The annual average temperature is between 15 and 25 °C, and the relative humidity of the air is above 83% all year round) as a source of fungal accumulation in bamboo leaves and their pathogenic nature. Our results provide precise knowledge for better managing bamboo forests and pave the way for isolating secondary metabolites and potential bioactive compounds.

Redox-responsive peptide-based complex coacervates as delivery vehicles with controlled release of proteinous drugs.

Proteinous drugs are highly promising therapeutics to treat various diseases. However, they suffer from limited circulation times and severe off-target side effects. Inspired by active membraneless organelles capable of dynamic recruitment and releasing of specific proteins, here, we present the design of coacervates as therapeutic protocells, made from small metabolites (anionic molecules) and simple arginine-rich peptides (cationic motif) through liquid-liquid phase separation. These complex coacervates demonstrate that their assembly and disassembly can be regulated by redox chemistry, which helps to control the release of the therapeutic protein. A model proteinous drugs, tissue plasminogen activator (tPA), can rapidly compartmentalize inside the complex coacervates, and the coacervates formed from peptides conjugated with arginine-glycine-aspartic acid (RGD) motif (a fibrinogen-derived peptide sequence), show selective binding to the thrombus site and thus enhance on-target efficacy of tPA. Furthermore, the burst release of tPA can be controlled by the redox-induced dissolution of the coacervates. Our proof-of-principle complex coacervate system provides insights into the sequestration and release of proteinous drugs from advanced drug delivery systems and represents a step toward the construction of synthetic therapeutic protocells for biomedical applications.

Recent Progress in Azobenzene-Based Supramolecular Materials and Applications.

Azobenzene-containing small molecules and polymers are functional photoswitchable molecules to form supramolecular nanomaterials for various applications. Recently, supramolecular nanomaterials have received enormous attention in material science because of their simple bottom-up synthesis approach, understandable mechanisms and structural features, and batch-to-batch reproducibility. Azobenzene is a light-responsive functional moiety in the molecular design of small molecules and polymers and is used to switch the photophysical properties of supramolecular nanomaterials. Herein, we review the latest literature on supramolecular nano- and micro-materials formed from azobenzene-containing small molecules and polymers through the combinatorial effect of weak molecular interactions. Different classes including complex coacervates, host-guest systems, co-assembled, and self-assembled supramolecular materials, where azobenzene is an essential moiety in small molecules, and photophysical properties are discussed. Afterward, azobenzene-containing polymers-based supramolecular photoresponsive materials formed through the host-guest approach, polymerization-induced self-assembly, and post-polymerization assembly techniques are highlighted. In addition to this, the applications of photoswitchable supramolecular materials in pH sensing, and CO2 capture are presented. In the end, the conclusion and future perspective of azobenzene-based supramolecular materials for molecular assembly design, and applications are given.

Fibrils Emerging from Droplets: Molecular Guiding Principles behind Phase Transitions of a Short Peptide-Based Condensate Studied by Solid-State NMR.

Biochemical reactions occurring in highly crowded cellular environments require different means of control to ensure productivity and specificity. Compartmentalization of reagents by liquid-liquid phase separation is one of these means. However, extremely high local protein concentrations of up to 400 mg/ml can result in pathological aggregation into fibrillar amyloid structures, a phenomenon that has been linked to various neurodegenerative diseases. Despite its relevance, the process of liquid-to-solid transition inside condensates is still not well understood at the molecular level. We thus herein use small peptide derivatives that can undergo both liquid-liquid and subsequent liquid-to-solid phase transition as model systems to study both processes. Using solid-state nuclear magnetic resonance (NMR) and transmission electron microscopy (TEM), we compare the structure of condensed states of leucine, tryptophan and phenylalanine containing derivatives, distinguishing between liquid-like condensates, amorphous aggregates and fibrils, respectively. A structural model for the fibrils formed by the phenylalanine derivative was obtained by an NMR-based structure calculation. The fibrils are stabilised by hydrogen bonds and side-chain π-π interactions, which are likely much less pronounced or absent in the liquid and amorphous state. Such noncovalent interactions are equally important for the liquid-to-solid transition of proteins, particularly those related to neurodegenerative diseases.

Alternative splicing: transcriptional regulatory network in agroforestry.

Alternative splicing (AS) in plants plays a key role in regulating the expression of numerous transcripts from a single gene in a regulatory pathway. Variable concentrations of growth regulatory hormones and external stimuli trigger alternative splicing to switch among different growth stages and adapt to environmental stresses. In the AS phenomenon, a spliceosome causes differential transcriptional modifications in messenger RNA (mRNAs), resulting in partial or complete retention of one or more introns as compared to fully spliced mRNA. Differentially expressed proteins translated from intron-retaining messenger RNA (mRNAir) perform vital functions in the feedback mechanism. At the post-transcriptional level, AS causes the remodeling of transcription factors (TFs) by the addition or deletion of binding domains to activate and/or repress transcription. In this study, we have summarized the specific role of AS in the regulation of gene expression through repression and activation of the transcriptional regulatory network under external stimuli and switch among developmental stages.

Primary plant nutrients modulate the reactive oxygen species metabolism and mitigate the impact of cold stress in overseeded perennial ryegrass.

Overseeded perennial ryegrass (Lolium perenne L.) turf on dormant bermudagrass (Cynodon dactylon Pers. L) in transitional climatic zones (TCZ) experience a severe reduction in its growth due to cold stress. Primary plant nutrients play an important role in the cold stress tolerance of plants. To better understand the cold stress tolerance of overseeded perennial ryegrass under TCZ, a three-factor and five-level central composite rotatable design (CCRD) with a regression model was used to study the interactive effects of nitrogen (N), phosphorus (P), and potassium (K) fertilization on lipid peroxidation, electrolyte leakage, reactive oxygen species (ROS) production, and their detoxification by the photosynthetic pigments, enzymatic and non-enzymatic antioxidants. The study demonstrated substantial effects of N, P, and K fertilization on ROS production and their detoxification through enzymatic and non-enzymatic pathways in overseeded perennial ryegrass under cold stress. Our results demonstrated that the cold stress significantly enhanced malondialdehyde, electrolyte leakage, and hydrogen peroxide contents, while simultaneously decreasing ROS-scavenging enzymes, antioxidants, and photosynthetic pigments in overseeded perennial ryegrass. However, N, P, and K application mitigated cold stress-provoked adversities by enhancing soluble protein, superoxide dismutase, peroxide dismutase, catalase, and proline contents as compared to the control conditions. Moreover, N, P, and, K application enhanced chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids in overseeded perennial ryegrass under cold stress as compared to the control treatments. Collectively, this 2-years study indicated that N, P, and K fertilization mitigated cold stress by activating enzymatic and non-enzymatic antioxidants defense systems, thereby concluding that efficient nutrient management is the key to enhanced cold stress tolerance of overseeded perennial ryegrass in a transitional climate. These findings revealed that turfgrass management will not only rely on breeding new varieties but also on the development of nutrient management strategies for coping cold stress.

Evaluation of data analytics workshop using RStudio amongst medical students in Pakistan.

A quasi-experimental study was conducted at the Aga Khan University, Karachi, Pakistan, to evaluate the outcomes of a series of workshops on 25 medical students' statistical knowledge and acceptance of RStudio. The knowledge in each of the five sessions was assessed using pre- and post- knowledge-based quizzes. In addition, the Student's Attitude Towards Statistics (SATS-36) and the Technology Acceptance Model were used. Data analysis on RStudio revealed a statistically significant improvement in knowledge in all five sessions (p<0.05). SATS-36 showed statistically significant improvement in Cognitive Competence (p<0.001). RStudio had commendable acceptance with relatively high scores of Attitudes (behavioural intention, median = 6.00 [5.20-7.00]) and Utility (perceived usefulness, median = 5.20 [4.10-6.20]). In conclusion, medical students had improved statistical knowledge and acceptance towards the novel statistical tool. Hence, further studies must evaluate the effectiveness of RStudio when integrated as part of the medical curriculum.

Genome-wide identification and expression analysis of metal tolerance protein (MTP) gene family in soybean (Glycine max) under heavy metal stress.

AIM: Plant metal tolerance proteins (MTPs) are plant membrane divalent cation transporters that specifically contribute to heavy metal stress resistance and mineral uptake. However, little is known about this family's molecular behaviors and biological activities in soybean. METHODS AND RESULTS: A total of 20 potential MTP candidate genes were identified and studied in the soybean genome for phylogenetic relationships, chromosomal distributions, gene structures, gene ontology, cis-elements, and previous gene expression. Furthermore, the expression of MTPs has been investigated under different heavy metals treatments. All identified soybean MTPs (GmaMTPs) contain a cation efflux domain or a ZT dimer and are further divided into three primary cation diffusion facilitator (CDF) groups: Mn-CDFs, Zn-CDFs, and Fe/Zn-CDFs. The developmental analysis reveals that segmental duplication contributes to the GmaMTP family's expansion. Tissue-specific expression profiling revealed comparative expression profiling in similar groups, although gene expression differed between groups. GmaMTP genes displayed biased responses in either plant leaves or roots when treated with heavy metal. In the leaves and roots, nine and ten GmaMTPs responded to at least one metal ion treatment. Furthermore, in most heavy metal treatments, GmaMTP1.1, GmaMTP1.2, GmaMTP3.1, GmaMTP3.2, GmaMTP4.1, and GmaMTP4.3 exhibited significant expression responses. CONCLUSION: Our findings provided insight into the evolution of MTPs in soybean. Overall, our findings shed light on the evolution of the MTP gene family in soybean and pave the path for further functional characterization of this gene family.

Integrating advancements in root phenotyping and genome-wide association studies to open the root genetics gateway.

Plant adaptation to challenging environmental conditions around the world has made root growth and development an important research area for plant breeders and scientists. Targeted manipulation of root system architecture (RSA) to increase water and nutrient use efficiency can minimize the adverse effects of climate change on crop production. However, phenotyping of RSA is a major bottleneck since the roots are hidden in the soil. Recently the development of 2- and 3D root imaging techniques combined with the genome-wide association studies (GWASs) have opened up new research tools to identify the genetic basis of RSA. These approaches provide a comprehensive understanding of the RSA, by accelerating the identification and characterization of genes involved in root growth and development. This review summarizes the latest developments in phenotyping techniques and GWAS for RSA, which are used to map important genes regulating various aspects of RSA under varying environmental conditions. Furthermore, we discussed about the state-of-the-art image analysis tools integrated with various phenotyping platforms for investigating and quantifying root traits with the highest phenotypic plasticity in both artificial and natural environments which were used for large scale association mapping studies, leading to the identification of RSA phenotypes and their underlying genetics with the greatest potential for RSA improvement. In addition, challenges in root phenotyping and GWAS are also highlighted, along with future research directions employing machine learning and pan-genomics approaches.

The impact of the COVID-19 pandemic on the career choice of medicine: A cross-sectional study amongst pre-medical students in Pakistan.

Background: The COVID-19 pandemic has significantly affected the lives of healthcare workers due to the frontline nature of their work. Their hard work and sacrifice have forged new perceptions of healthcare workers. These changes may potentially influence students' interest in medicine. This study explores how the COVID-19 pandemic has affected premedical students' decisions to pursue medicine as a career. Methods: A cross-sectional study using a self-designed online questionnaire was carried out amongst pre-medical students across Pakistan. Results: A total of 1695 students from 93 public and private schools filled in the survey. After the onset of the COVID-19 pandemic, significantly more pre-medical students want to pursue medicine (60.7%-62.9%) and less are unsure (20.2%-17%). Students are significantly more likely to be motivated to pursue medicine due to altruistic benefits to society (57% vs. 62.7%) and be deterred by the risk of contracting infections on duty (10%-14.6%). There is a minor but significant increase in the popularity of internal medicine (17.1%-18.9%), public health (4.1% vs. 5.7%), emergency medicine (3.8% vs. 5.7%), pediatrics (3.8% vs. 4.7%), and radiology (2.1% vs. 2.9%). Most pre-medical students felt that doctors routinely undergo physical and emotional turmoil (84%). Conclusions: Although awareness of hardships faced by medical professionals has increased, motivation to pursue medicine has grown. Through understanding trends in the motivations of students to pursue medicine, medical schools can accommodate the expectations of incoming students and reach out to potential applicants.

Peptide-Based Coacervate-Core Vesicles with Semipermeable Membranes.

Coacervates droplets have long been considered as potential protocells to mimic living cells. However, these droplets lack a membrane and are prone to coalescence, limiting their ability to survive, interact, and organize into higher-order assemblies. This work shows that tyrosine-rich peptide conjugates can undergo liquid-liquid phase separation in a well-defined pH window and transform into stable membrane-enclosed protocells by enzymatic oxidation and cross-linking at the liquid-liquid interface. The oxidation of the tyrosine-rich peptides into dityrosine creates a semipermeable, flexible membrane around the coacervates with tunable thickness, which displays strong intrinsic fluorescence, and stabilizes the coacervate protocells against coalescence. The membranes have an effective molecular weight cut-off of 2.5 kDa, as determined from the partitioning of small dyes and labeled peptides, RNA, and polymers into the membrane-enclosed coacervate protocells. Flicker spectroscopy reveals a membrane bending rigidity of only 0.1kB T, which is substantially lower than phospholipid bilayers despite a larger membrane thickness. Finally, it is shown that enzymes can be stably encapsulated inside the protocells and be supplied with substrates from outside, which opens the way for these membrane-bound compartments to be used as molecularly crowded artificial cells capable of communication or as a vehicle for drug delivery.