Emergence Of Drug Resistance Research Articles

Parasites and Microbiota: Dual Interactions and Therapeutic Perspectives

The human gut hosts a diverse and active community of bacteria that symbiotically support the physiology, metabolism, and immunity of the intestinal lining. Nevertheless, a dynamic community of parasites (helminths and protozoa) may share a habitat with gut-dwelling microbiota. Both microbiota and parasites can significantly change the physical and immunological environment of the gut, thus generating several mechanisms of interaction. Studying this field is crucial for understanding the pathogenesis of parasitic diseases. Additionally, intestinal microbiota and gut-dwelling parasites may interact with each other and with the host immunity to alleviate or exacerbate the disease. These interactions can alter the pathogenicity of both parasites and microbiota, thereby changing the infection outcomes and the overall disease profile. Parasites and microbiota interactions occur via several mechanisms, including physical alteration in both the gastrointestinal microenvironment and the adaptive and innate immune responses. By modulating the microbiota, treating parasitic infections and microbiota dysbiosis may be improved through knowing the mechanisms and consequences of the interactions between intestinal parasites and the microbiota. Thus, new biological tools of treatment including probiotics can be introduced, particularly with the emergence of drug resistance and adverse effects.

Genome-wide CRISPR screens identify CLC-2 as a drug target for anti-herpesvirus therapy: tackling herpesvirus drug resistance.

The emergence of drug resistance to virus (i.e., acyclovir (ACV) to herpesviruses) has been termed one of the common clinical issues, emphasizing the discovery of new antiviral agents. To address it, a genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) screening was performed in mouse haploid embryonic stem cells infected with pseudorabies virus (PRV), an α-herpesvirus causing human and pig diseases. The results demonstrated that type 2 voltage-gated chloride channels (CLC-2) encoded by one of the identified genes, CLCN2, is a potential drug target for anti-herpesvirus therapy. CLC-2 inhibitors, omeprazole (OME) and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), can efficiently inhibit infection of multiple herpesviruses in cellulo (i.e., PRV, HSV and EBV), and effectively treat murine herpes simplex encephalitis (HSE). Additionally, DIDS was found to inhibit HSV-1 replication by blocking the PI3K/Akt pathway. Most importantly, both DIDS and OME were able to inhibit ACV-resistant HSV-1 strain infection. The study's findings suggest that targeting host-cell factors such as CLC-2 may be a promising approach to tackling herpesvirus drug resistance. The discovery of CLC-2 as a potential drug target for anti-herpesvirus therapy provides a new direction for the development of novel antiviral agents.

Rates of Viral Non-Suppression and Acquired HIV-1 Drug Resistance Emergence among Children during the Sociopolitical Crisis in the Northwest Region of Cameroon: A Call for Improved Monitoring Strategies.

Virological failure (VF) among children remains concerning, with high risks of HIV drug resistance (HIVDR) emergence and increased disease progression. Therefore, monitoring of viral non-suppression and emerging HIVDR is crucial, especially in the frame of sociopolitical unrest. The study sought to determine the prevalence of VF and evaluate the acquired HIVDR and viral genetic diversity among children in the northwest region of Cameroon during the ongoing sociopolitical crisis. A cross-sectional facility-based study was conducted among HIV-infected children aged ≤18 years, receiving antiretroviral therapy (ART) in urban and rural settings of Northwest Cameroon, from November 2017 through May 2018. Viral load (VL) was done using the Abbott m2000RealTime. Unsuppressed VL was defined as viral load ≥1,000 copies/ml. HIVDR testing was performed by sequencing of HIV-1 protease-reverse transcriptase at the Chantal Biya International Reference Center (CIRCB) using an in-house protocol. Drug resistance mutations (DRM) were interpreted using Stanford HIVdbv8.5 and phylogeny using MEGAv.6. Data were compared between urban and rural areas with p<0.05 considered statistically significant. A total of 363 children were recruited, average age of 12 years (urban) and 8 years (rural). VL coverage was 100% in the urban setting and 77% in the rural setting. Overall, VF was 40.5% (39% [130/332] in the urban setting and 41% (13/31) in the rural setting; p=0.45). Overall, viral undetectability (defined as VL<40 copies/ml) was 45.5% (46% (urban) and 45% (rural); p=0.47). Among those experiencing confirmed virological failure and who were successfully sequenced (n=35), the overall rate of HIVDR was 100% (35/35). By drug class, HIVDR rates were 97.1% (34/35) for non-nucleoside reverse transcriptase inhibitors (NNRTIs), 97.1% (34/35) for NRTIs and 17.1% (6/35) for protease inhibitors (22.7% (5/22) in the urban setting and 7.7% [1/13] in the rural setting). CRF02_AG was the most prevalent viral clade (75%), followed by other recombinants (09_cpx, 11_cpx, 13_cpx, 22_01A1, 37_cpx) and pure subtypes (A1, F2, G, H). In this population of children and adolescents living with HIV in a context of socio-political instability in the North-West region of Cameroon, rates of viral non-suppression are high, and accompanied by HIVDR selection. Our suggests the need for a more differentiated care of these CAHIV, especially those in these regions faced with significant socio-economic and health impacts due to the ongoing crisis.

A promising class of Antiprotozoal agents, design and synthesis of novel Pyrimidine–Cinnamoyl Hybrids

Malaria, caused by parasitic protozoans of the Plasmodium genus, continues to be one of the greatest global health crises, especially in Africa. The emergence of antimalarial drug resistance continues to be a health problem necessitating an urgent need for alternative and cost-effective antimalarials. Using a molecular hybridization approach, we report the design and synthesis of an efficacious novel class of antiprotozoal agents; (E)-1-(4-(4,6-diphenylpyrimidin-2-yl)piperazin-1-yl)-3-phenyl prop-2-en-1-one derivatives (8a-r). The in vitro inhibitory activity of the synthesized compounds was evaluated against the NF54 chloroquine-sensitive strain of Plasmodium falciparum. From the antiprotozoal screening, three compounds displayed propitious activity with IC50 values (0.18-0.21μM), using quinine and chloroquine as standard antimalarials. Compounds 8o and 8l emerged as the most potent candidates with IC50 values of 0.18 ± 0.02 μM and 0.21 ± 0.001 μM with an associated good safety index of 18.59 and 16.75 to human kidney epithelial (HEK293) cells, respectively. The synthesized analogues present a new chemical architecture structurally unrelated to the current regime of antimalarial drugs, representing a valid strategy to combat resistance in P. falciparum species to current commercial drugs. We further investigated the binding affinities of the compounds against recombinant forms of two P. falciparum heat shock protein 70 homologues; PfHsp70-1 and PfHsp70-z, both of which are essential and promising druggable candidates. Compound 8l exhibited the highest binding affinity for both PfHsp70s. Furthermore, molecular docking revealed that compounds 8k, 8l, 8m, and 8o exhibited better fitness to PfHsp70-1, with compounds 8l and 8o showing the highest binding affinity of 10.5 kcal/mol and 10.1 kcal/mol, respectively. Therefore, it can be speculated that PfHsp70-1 may be a possible target of some of the inhibitors tested in this study. The presence of electron-donating groups on the phenyl ring of 4,6-pyrimidine moiety and cinnamoyl group demonstrated a positive correlation between the observed computational data and the biological activity. Taken together, this paper demonstrates the importance of using the molecular hybridization approach in the development of newer cinnamoyl clubbed with 4,6-diphenyl pyrimidine hybrids as potential antiprotozoal agents.

Invasive candidiasis in a pediatric tertiary hospital: Epidemiology, antifungal susceptibility, and mortality rates.

Invasive infections caused by non-albicans Candida are increasing worldwide. However, there is still a lack of information on invasive candidiasis (IC) in the pediatric setting, including susceptibility profiles and clonal studies. We investigated the clinical, epidemiologic, and laboratory characteristics of IC, possible changes in antifungal susceptibility profiles over time, and the occurrence of clonality in our tertiary children's hospital. We analyzed 123 non-duplicate Candida isolates from sterile sites of pediatric patients in a tertiary hospital in southern Brazil, between 2016 and 2021. Data on demographics, comorbidities, and clinical outcomes were collected. Candida species distribution, antifungal susceptibility profiles, biofilm production, and molecular epidemiology of isolates were assessed using reference methods. The range of IC incidence was 0.88-1.55 cases/1000 hospitalized patients/year, and the IC-related mortality rate was 20.3%. Of the total IC cases, 42.3% were in patients aged<13 months. Mechanical ventilation, parenteral nutrition, and intensive care unit (ICU) admission were common in this group. In addition, ICU admission was identified as a risk factor for IC-related mortality. The main site of Candida spp. isolation was blood, and non-albicans Candida species were predominant (70.8%). No significant clonal spread was observed among isolates of the three most commonly isolated species, and 99.1% of all isolates were biofilm producers. Non-albicans Candida species were predominant in this study. Notably, clonal expansion and emergence of antifungal drug resistance were not observed in our pediatric setting.

In vitro and silico activity of piperlongumine against azole-susceptible/resistant Aspergillus fumigatus and terbinafine-susceptible/resistant Trichophyton species

In recent years, the widespread emergence of drug resistance in yeasts and filamentous fungi to existing antifungal armamentariums has become a severe threat to global health. There is also concern regarding increased rates of azole resistance in Aspergillus fumigatus and Terbinafine resistance in Trichophyton species. To overcome this concern of resistance to regular therapies, new antifungal drugs with novel and effective mechanisms are crucially needed. Herbal remedies may be promising strategies for the treatment of resistant infections. We aimed to investigate the in vitro and silico activity of piperlongumine against clinical azole susceptible/resistant A. fumigatus and terbinafine-susceptible/resistant Trichophyton species. In the current study, piperlongumine demonstrated potent antifungal activity, with minimum inhibitory concentrations (MICs) ranging from 0.016-4 μg/mL against Trichophyton isolates and 0.25-2 μg/mL for A. fumigatus isolates. Additionally, molecular docking studies indicated that piperlongumine has a strong binding affinity to the active sites of squalene epoxidase and sterol 14-alpha demethylase. However, further studies are warranted to correlate these findings with clinical outcomes and provide the basis for further investigations to pave the way for developing novel antifungal agents.

PATHOEXTRACT: A BIOINFORMATIC PIPELINE FOR QUALITY CONTROL AND HOST DNA REMOVAL IN PLASMODIUM FALCIPARUM NGS DATA

Malaria, caused by Plasmodium falciparum, is a significant global health burden, particularly in sub-Saharan Africa. Deep sequencing (NGS) of parasite genomes has revolutionized our understanding of its biology and the emergence of drug resistance. However, the presence of host human DNA and other microbial contaminants within patient samples can hinder accurate and efficient parasite genome analysis. To address this challenge, we have developed PathoExtract, a robust bioinformatics pipeline that integrates commonly used tools into a streamlined workflow. PathoExtract leverages Snakemake, a workflow management system, to provide a flexible and reproducible framework for data processing. The pipeline incorporates rigorous quality control steps to identify and remove low-quality reads and contaminants. Host DNA and microbial sequences are effectively filtered out using a combination of alignment-based and alignment-free methods, ensuring that only Plasmodium falciparum reads are retained for downstream analysis.The pipeline offers an intuitive graphical user interface, making it accessible to researchers with varying levels of bioinformatics expertise. This user-friendly interface simplifies the process of running the pipeline, even for those unfamiliar with command-line tools. The code and documentation for PathoExtract are freely available at: https://github.com/stanlasso/DREPAL-PATHOEXTRACT.

Dynamics and Evolution of Donor-derived Cytomegalovirus Infection in 3 Solid Organ Transplant Recipients With the Same Multiorgan Donor.

Cytomegalovirus (CMV) infection poses a significant risk to immunosuppressed transplant recipients, manifesting through primary infection, reinfection, or reactivation. We analyzed the emergence of drug resistance in CMV infection in 3 patients who were later found to have received an allograft from a shared, deceased donor. The seronegative transplant recipients developed symptomatic CMV infections after bowel/pancreas, kidney, or lung transplantation. Prospective Sanger sequencing was used to identify mutations in the viral DNA polymerase (DP) and protein kinase (PK). DP and PK variants were retrospectively quantified by targeted next-generation sequencing. The impact of the novel DP-A505G substitution on drug susceptibility was assessed using a recombinant virus. Whole-genome sequencing of clinical CMV samples was enabled through target DNA enrichment. The DP-A505G substitution was found in all patient samples and could be associated with a natural polymorphism. A subsequent review of the patients' clinical histories revealed that they had all received organs from a single donor. The CMV infection exhibited divergent evolution among the patients: patient 1 developed resistance to ganciclovir and foscarnet because of 2 DP mutations (V715M and V781I), patient 2 showed no genotypic resistance, and patient 3 developed ganciclovir (PK-L595S) and maribavir resistance (PK-T409M). Interpatient variation across the entire CMV genome was minimal, with viral samples clustering in phylogenetic analysis. All 3 transplant recipients were infected with the same donor-derived CMV strain and readily developed different drug susceptibility profiles. This underscores the importance of judicious antiviral drug use and surveillance in preventing antiviral resistance emergence.

QSAR Modeling, Molecular Docking and ADMET Study of Aryl Fluorosulfate Derivatives as Potential Anti-TB Agents

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb) infection, stands as a global infectious disease presenting substantial public health challenges due to its high incidence and mortality rates. The prolonged use of conventional anti-TB therapies has led to the emergence of severe drug resistance in Mtb, resulting in extended treatment durations, increased costs, poor patient compliance, and reduced cure rates. This phenomenon has posed a significant burden on global TB prevention and control efforts, necessitating a shift in research focus toward the exploration of novel anti-TB drugs. In this context, utilizing QSAR modeling methods, our study systematically investigated the relationship between the chemical structures of 36 aryl fluorosulfate derivatives and their inhibitory activity against Mtb. Robust and predictive Topomer CoMFA and HQSAR models were developed, featuring Topomer CoMFA model parameters: q 2 = 0.659, r 2 = 0.969, F = 102.877, N = 6, SEE = 0.138; HQSAR model parameters: q 2 = 0.705, r 2 = 0.873, SEE = 0.264, HL = 199, N = 4. Leveraging these models, structural modifications were applied to the compounds using the ZINC15 database, leading to the successful design and screening of three novel compounds with desirable inhibitory activity. Molecular docking and ADMET performance prediction results indicated that these three new compounds exhibit strong binding capabilities and promising pharmaceutical potential. This study provides valuable insights and research directions for the development of aryl fluorosulfate derivatives as potential agents for tuberculosis treatment and as novel drugs.

APITHERAPY AND APPLICATIONS IN VETERINARY MEDICINE

The use of bees and bee products for therapeutic purposes in human and veterinary medicine is called apitherapy. Natural products have been used throughout human history to protect against and treat diseases. In recent years, the emergence of drug resistance and the occurrence of adverse effects associated with the indiscriminate and irregular use of pharmacological agents have prompted humanity to pursue alternative solutions. One of the most significant solutions is the administration of bee products. The use of bee products in apitherapy applications includes honey, bee venom, pollen, propolis, beeswax, royal jelly, perga and apilarnil (bee larvae). In general, apitherapy products with a wide range of indications are widely used in various system diseases and some dermatologic problems and various effects of these products such as antibacterial, antifungal, antiviral, antioxidant, anticarcinogenic, anti-inflammatory, antidiabetic and immunomodulatory effects in vitro and in vivo have been investigated in many different studies. Apitherapy is less common in veterinary practice than in human medicine. Additionally, bee products are employed in the treatment of other animal diseases, including gastrointestinal disorders, otitis, sinusitis, ophthalmic conditions, dermatological disorders, and skin care. Additionally, bee products are employed as food supplements for animals. The most prevalent additive in animal food is bee pollen. It has been demonstrated to promote growth, reduce mortality and prevent morbidity. Apitherapy has gained importance in the field of veterinary medicine in recent years in order to prevent both human health and economic losses, especially in the treatment of animals consumed as food.

Evidence of Human-designated Antiretroviral (ARV) Drug Residues in Broiler Chicken, Domestic Pigs, and Animal Feeds in Tanzania.

Recent reports have indicated the use of antiretroviral (ARV) drugs to boost animal production in neighboring Uganda, with further reports of use in several African countries. This cross-sectional study was conducted in nine districts in Tanzania, and involved screening for the presence of three first-line ARVs (lamivudine, nevirapine, and efavirenz) residues in the muscle and blood of domestic pigs and broiler chickens, and in sampled animal feed and water. Residues were determined using liquid chromatography and mass spectrometry (LC-MS/MS). The method involved calibration of the lower limit of quantitation (LLOQ) and limit of detection (LOD). ARVs were detected and quantified using the Multiple Reaction Monitoring (MRM) system. 131 (66.8%) of the 196 samples of muscle, blood, and animal feed were found to contain lamivudine residues, with the highest concentration detected in domestic pig blood and muscle (7.58mg/kg) and the lowest concentration (0.01 mg/kg) in broiler chicken feed. There was a significant relationship between the presence of lamivudine by sample type and sample origin (p=0.000). Nevirapine and efavirenz drugs were not detected in any of the collected samples. No ARV residues were detected in water samples (n=37). This study confirms the use of ARVs in animal production in Tanzania as evidenced by the presence of residues in animal feeds. We found lamivudine residues in domestic pigs and broiler chickens at concentrations higher than those recently reported in other East African studies. Farmers living with HIV may be using ARVs from their prescribed medications, which may lead to poor adherence and the emergence of drug resistance. Besides direct human and animal health issues, these residues in animal feeds and animal excreta can lead to environmental contamination leading to several negative impacts. We recommend a total ban on human-designated ARVs in animal production and advocate for comprehensive studies and monitoring systems across African countries to reveal potential societal and other reasons for their use and provide comprehensive solutions using One Health approaches.

New Therapies and Strategies to Curb HIV Infections with a Focus on Macrophages and Reservoirs.

More than 80 million people worldwide have been infected with the human immunodeficiency virus (HIV). There are now approximately 39 million individuals living with HIV/acquired immunodeficiency syndrome (AIDS). Although treatments against HIV infection are available, AIDS remains a serious disease. Combination antiretroviral therapy (cART), also known as highly active antiretroviral therapy (HAART), consists of treatment with a combination of several antiretroviral drugs that block multiple stages in the virus replication cycle. However, the increasing usage of cART is inevitably associated with the emergence of HIV drug resistance. In addition, the development of persistent cellular reservoirs of latent HIV is a critical obstacle to viral eradication since viral rebound takes place once anti-retroviral therapy (ART) is interrupted. Thus, several efforts are being applied to new generations of drugs, vaccines and new types of cART. In this review, we summarize the antiviral therapies used for the treatment of HIV/AIDS, both as individual agents and as combination therapies, and highlight the role of both macrophages and HIV cellular reservoirs and the most recent clinical studies related to this disease.

The Synergistic Effect of Baloxavir and Neuraminidase Inhibitors against Influenza Viruses In Vitro.

Influenza viruses remain a major threat to human health. Four classes of drugs have been approved for the prevention and treatment of influenza infections. Oseltamivir, a neuraminidase inhibitor, is a first-line anti-influenza drug, and baloxavir is part of the newest generation of anti-influenza drugs that targets the viral polymerase. The emergence of drug resistance has reduced the efficacy of established antiviral drugs. Combination therapy is one of the options for controlling drug resistance and enhancing therapeutical efficacies. Here, we evaluate the antiviral effects of baloxavir combined with neuraminidase inhibitors (NAIs) against wild-type influenza viruses, as well as influenza viruses with drug-resistance mutations. The combination of baloxavir with NAIs led to significant synergistic effects; however, the combination of baloxavir with laninamivir failed to result in a synergistic effect on influenza B viruses. Considering the rapid emergence of drug resistance to baloxavir, we believe that these results will be beneficial for combined drug use against influenza.

The clinical significance of pyogenic liver abscess after transarterial chemoembolization or microwave ablation on malignant liver tumors: A retrospective study.

Pyogenic liver abscess (PLA) is a rare but severe complication of interventional therapy that has been little studied. We aimed to find the risk factors for PLA after transarterial chemoembolization (TACE) or microwave ablation (MWA), further explore its clinical significance and summarize our experience with its treatment. Twenty-two patients with PLA and 118 randomly selected patients without PLA after TACE/MWA were enrolled. Logistic regression was used to analyze risk factors, a nonparametric test was used to compare recovery duration, the log-rank test was used to compare progression-free survival, and Spearman correlation coefficient was calculated between the time from fever to drainage and the total duration of fever. The disease process and treatment were summarized. Sphincter of Oddi manipulation increased the risk of PLA by 70.781-fold. The PLA group took longer to recover (36.56 ± 16.42 days) than the control group (5.54 ± 4.33 days), and had a shorter progression-free survival. Escherichia coli was the major pathogenic bacterium, and multidrug resistance was found in 8 patients with E coli or Enterococcus faecium. The time from fever to drainage was 15.89 ± 13.78 days, which was positively correlated with the total duration of fever (24.29 ± 18.24 days). Overall, 18 patients recovered, and 4 patients died of PLA, for a mortality rate of 18.18%. The fever of 10 patients (45.45%) was controlled by cefoperazone sodium and sulbactam sodium or piperacillin sodium and tazobactam sodium; the fever of 7 patients (31.81%) was controlled by imipenem and cilastatin sodium; and the fever of 3 patients (13.63%) was controlled by tigecycline. Sphincter of Oddi manipulation is a high-risk factor for PLA after TACE or MWA. PLA can accelerate cancer progression and even lead to death. E coli was the major pathogenic bacterium, and multidrug resistance was most common in E coli and E faecium. Timely drainage and appropriate antibiotics are the key primary measures for treating PLA. Cefoperazone sodium and sulbactam sodium or piperacillin sodium and tazobactam sodium is a good choice for the first treatment of PLA, especially before pathogenic bacteria are identified. With the emergence of drug resistance, imipenem and cilastatin sodium, and tigecycline can be used for posterior treatment.

ASLdC3: A Derivative of Acidic Sophorolipid Disrupts Mitochondrial Function, Induces ROS Generation, and Inhibits Biofilm Formation in Candida albicans.

Fungal infections account for more than 140 million cases of severe and life-threatening conditions each year, causing approximately 1.7 million deaths annually. Candida albicans and related species are the most common human fungal pathogens, causing both superficial (mucosal and cutaneous) and life-threatening invasive infections (candidemia) with a 40-75% mortality rate. Among many virulence factors of Candida albicans, morphological transition from yeast to hyphae, secretion of hydrolytic enzymes, and formation of biofilms are considered to be crucial for pathogenicity. However, the arsenals for the treatment against these pathogens are restricted to only a few classes of approved drugs, the efficacy of which is being compromised by host toxicity, fungistatic activity, and the emergence of drug resistance. In this study, we have described the development of a molecule, exhibiting excellent antifungal activity (MIC 8 μg/mL), by tailoring acidic sophorolipids with aryl alcohols via enzyme catalysis. This novel derivative, ASLdC3, is a surface-active compound that lowers the surface tension of the air-water interface up to 2-fold before reaching the critical micelle concentration of 25 μg/mL. ASLdC3 exhibits excellent antibiofilm properties against Candida albicans and other nonalbicans Candida species. The molecule primarily exhibits its antifungal activity by perturbing mitochondrial function through the alteration of the mitochondrial membrane potential (MMP) and generation of reactive oxygen species (ROS). The ROS damages fungal cell membrane function and cell wall integrity, eventually leading to cell death. ASLdC3 was found to be nontoxic in in vitro assay and nonhemolytic. Besides, it does not cause toxicity in the C. elegans model. Our study provides a valuable foundation for the potential of acidic sophorolipid as a nontoxic, biodegradable precursor for the design and synthesis of novel molecules for use as antimicrobial drugs as well as for other clinical applications.

201 Transcriptome analysis of bovine abomasal mucosa following experimental infection with Ostertagia ostertagi

Abstract Ostertagia ostertagi is a cattle stomach nematode that causes significant disease; however, little is known about host responses to infection. Due to the emergence of drug resistance in these parasites, there is a need for alternative treatments. To understand host responses to O. ostertagi infection in the gastric mucosa, gene expression in fundic and pyloric mucosa was compared between infected and uninfected calves for 21 d post-infection. The number of differentially expressed genes (DEGs) increased over time with more upregulated than downregulated DEGs at each time point. Fundic mucosa had more DEGs than pyloric mucosa across all time points. The largest changes occurred between d 7 to 9 and 10 post-infection. Most DEGs are associated with immunity, cellular reorganization, cell migration, and proliferation. Tuft/epithelial cell response to the infection was atypical, lacking key cytokines. Numerous genes associated with T cell exhaustion were upregulated. The data collectively indicate that O. ostertagi infection elicited host immune responses, yet also suggest parasite-induced immunosuppression is present. This may explain why cattle are slow in developing protective immunity to O. ostertagi. Understanding mechanisms of parasite evasion will facilitate the rational design of protective vaccines against complex nematode parasites.

Elucidating the Substrate Envelope of Enterovirus 68-3C Protease: Structural Basis of Specificity and Potential Resistance.

Enterovirus-D68 (EV68) has emerged as a global health concern over the last decade with severe symptomatic infections resulting in long-lasting neurological deficits and death. Unfortunately, there are currently no FDA-approved antiviral drugs for EV68 or any other non-polio enterovirus. One particularly attractive class of potential drugs are small molecules inhibitors, which can target the conserved active site of EV68-3C protease. For other viral proteases, we have demonstrated that the emergence of drug resistance can be minimized by designing inhibitors that leverage the evolutionary constraints of substrate specificity. However, the structural characterization of EV68-3C protease bound to its substrates has been lacking. Here, we have determined the substrate specificity of EV68-3C protease through molecular modeling, molecular dynamics (MD) simulations, and co-crystal structures. Molecular models enabled us to successfully characterize the conserved hydrogen-bond networks between EV68-3C protease and the peptides corresponding to the viral cleavage sites. In addition, co-crystal structures we determined have revealed substrate-induced conformational changes of the protease which involved new interactions, primarily surrounding the S1 pocket. We calculated the substrate envelope, the three-dimensional consensus volume occupied by the substrates within the active site. With the elucidation of the EV68-3C protease substrate envelope, we evaluated how 3C protease inhibitors, AG7088 and SG-85, fit within the active site to predict potential resistance mutations.

Impact of Environmental Laws Pertaining to Pollution Problems in Pharma and Chemical Sectors in India

Medical waste is regarded as a hazardous waste of a specific kind because of its high toxicity, presence of radioactive and toxic compounds, and propensity to cause sickness. The degree to which bacteria and viruses are present in medical waste, the dosage and type of exposure, and the degree to which the body is resistant to these pathogens Trash from isolation rooms for patients with infectious disorders, bacterial, infectious, and biological agent residues, waste from sterilization and disinfection, blood, serums, and plasma, and pharmaceutical residues are all considered to be medical waste. This manual offers suggestions for reducing trash creation through source reduction and recycling as well as an explanation of the processes that produce waste in hospitals. Hospitals will benefit by restricting the age of these materials at the source or reusing the wastes on or off site in light of the fact that doing so will limit removal expenses and liabilities connected with discarding hazardous waste. Compared to industrial facilities, general medical and surgical hospitals produce less hazardous wastes overall, although they do so in a number of different forms. Pharmaceuticals were formerly believed to enter the environment largely through usage or improper disposal. It was discovered that some production facilities were the sources of substantially higher ambient concentrations than those brought on by drug use. For both authorities and the pharmaceutical industry, the widespread discovery of waste medicines in environmental samples and the dangers posed by their introduction into wildlife habitats are key issues. Pharmaceutical firms should understand that reducing drug use and environmental damage is in their own best interests because doing so will prevent the emergence of drug resistance, which will prolong the shelf life of their medications. Changes in public and worldwide regulations, the reception of reasonable environmental principles inside current business standards, and requests from medical care suppliers and patients are likely impetuses for activity. Yet, clients can't pursue taught decisions because of the shortage of data about the wellspring of drugs and the impacts of creation on the climate. We suggest that one of several crucial strategies for lowering pollution from medicine manufacture would be improved transparency throughout the entire production chain.

Cancer drug-tolerant persister cells: from biological questions to clinical opportunities.

The emergence of drug resistance is the most substantial challenge to the effectiveness of anticancer therapies. Orthogonal approaches have revealed that a subset of cells, known as drug-tolerant 'persister' (DTP) cells, have a prominent role in drug resistance. Although long recognized in bacterial populations which have acquired resistance to antibiotics, the presence of DTPs in various cancer types has come to light only in the past two decades, yet several aspects of their biology remain enigmatic. Here, we delve into the biological characteristics of DTPs and explore potential strategies for tracking and targeting them. Recent findings suggest that DTPs exhibit remarkable plasticity, being capable of transitioning between different cellular states, resulting in distinct DTP phenotypes within a single tumour. However, defining the biological features of DTPs has been challenging, partly due to the complex interplay between clonal dynamics and tissue-specific factors influencing their phenotype. Moreover, the interactions between DTPs and the tumour microenvironment, including their potential to evade immune surveillance, remain to be discovered. Finally, the mechanisms underlying DTP-derived drug resistance and their correlation with clinical outcomes remain poorly understood. This Roadmap aims to provide a comprehensive overview of the field of DTPs, encompassing past achievements and current endeavours in elucidating their biology. We also discuss the prospect of future advancements in technologies in helping to unveil the features of DTPs and propose novel therapeutic strategies that could lead to their eradication.

Exosomes: Key Factors in Ovarian Cancer Peritoneal Metastasis and Drug Resistance.

Ovarian cancer remains a leading cause of death among gynecological cancers, largely due to its propensity for peritoneal metastasis and the development of drug resistance. This review concentrates on the molecular underpinnings of these two critical challenges. We delve into the role of exosomes, the nano-sized vesicles integral to cellular communication, in orchestrating the complex interactions within the tumor microenvironment that facilitate metastatic spread and thwart therapeutic efforts. Specifically, we explore how exosomes drive peritoneal metastasis by promoting epithelial-mesenchymal transition in peritoneal mesothelial cells, altering the extracellular matrix, and supporting angiogenesis, which collectively enable the dissemination of cancer cells across the peritoneal cavity. Furthermore, we dissect the mechanisms by which exosomes contribute to the emergence of drug resistance, including the sequestration and expulsion of chemotherapeutic agents, the horizontal transfer of drug resistance genes, and the modulation of critical DNA repair and apoptotic pathways. By shedding light on these exosome-mediated processes, we underscore the potential of exosomal pathways as novel therapeutic targets, offering hope for more effective interventions against ovarian cancer's relentless progression.