MIMESIS: minimal DNA-methylation signatures to quantify and classify tumor signals in tissue and cell-free DNA samples.

DNA-methylation alterations are common in cancer and display unique characteristics that make them ideal markers for tumor quantification and classification. Here we present MIMESIS, a computational framework exploiting minimal DNA-methylation signatures composed by a few dozen informative DNA-methylation sites to quantify and classify tumor signals in tissue and cell-free DNA samples. Extensive analyses of multiple independent and heterogenous datasets including >7200 samples demonstrate the capability of MIMESIS to provide precise estimations of tumor content and to enable accurate classification of tumor type and molecular subtype. To assess our framework for clinical applications, we designed a MIMESIS-informed assay incorporating the minimal signatures for breast cancer. Using both artificial samples and clinical serial cell-free DNA samples from patients with metastatic breast cancer, we show that our approach provides accurate estimations of tumor content, sensitive detection of tumor signal and the ability to capture clinically relevant molecular subtype in patients' circulation. This study provides evidence that our extremely parsimonious approach can be used to develop cost-effective and highly scalable DNA-methylation assays that could support and facilitate the implementation of precision oncology in clinical practice.

Impact of Exposure to Vaccination and Infection on Cellular and Antibody Response to SARS-CoV-2 in CVID Patients Through COVID-19 Pandemic.

PURPOSE: The purpose of this study is to investigate the kinetics of response against SARS-CoV-2 elicited by vaccination and/or breakthrough infection (occurred after 3 doses of BNT162b2) in a cohort CVID patients. METHODS: We measured humoral and cellular immunity using quantitative anti-spike antibody (anti-S-IgG) and neutralization assay and specific interferon-gamma release assay (IGRA) before and after the third or fourth dose of BNT162b2 and/or after COVID-19. RESULTS: In CVID, 58.3% seroconverted after 2 doses that increased to 77.8% after 3 doses. Between the second and third dose, there was a decline in humoral compartment that led to titers below the cutoff of 1:10 (MNA90%) in CVID. This was paralleled by a significantly lower proportion (30%) and reduced magnitude of the residual cellular response among CVID. The third dose achieved a lower titer of anti-S and nAb against the Wuhan strain than HC and significantly decreased the rate of those showing solely a positive neutralizing activity and those with simultaneous negativity of IGRA and nAbs; the differences in IGRA were overall reduced with respect to HC. At further sampling after breakthrough SARS-COV-2 infection, mostly in the omicron era, or fourth dose, 6 months after the last event, the residual nAb titer to Wuhan strain was still significantly higher in HC, while there was no significant difference of nAbs to BA.1. The rate of IGRA responders was 65.5% in CVID and 90.5% in HC (p=0.04), while the magnitude of response was similar. None of CVID had double negativity to nAbs and IGRA at the last sampling. CONCLUSION: This data shows an increase of adaptive immunity in CVID after mRNA vaccination in parallel to boosters, accrual number of exposures and formation of hybrid immunity.

Hylin-a1: A Pan-Inhibitor against Emerging and Re-Emerging Respiratory Viruses.

Pandemic and epidemic outbreaks of respiratory viruses are a challenge for public health and social care system worldwide, leading to high mortality and morbidity among the human populations. In light of the limited efficacy of current vaccines and antiviral drugs against respiratory viral infections and the emergence and re-emergence of new viruses, novel broad-spectrum antiviral drugs are needed for the prevention and treatment of these infections. Antimicrobial peptides with an antiviral effect, also known as AVPs, have already been reported as potent inhibitors of viral infections by affecting different stages of the virus lifecycle. In the present study, we analyzed the activity of the AVP Hylin-a1, secreted by the frog Hypsiboas albopunctatus, against a wide range of respiratory viruses, including the coronaviruses HCoV-229E and SARS-CoV-2, measles virus, human parainfluenza virus type 3, and influenza virus H1N1. We report a significant inhibitory effect on infectivity in all the enveloped viruses, whereas there was a lack of activity against the naked coxsackievirus B3. Considering the enormous therapeutic potential of Hylin-a1, further experiments are required to elucidate its mechanism of action and to increase its stability by modifying the native sequence.

Evaluation of humoral and cellular response to third dose of BNT162b2 mRNA COVID-19 vaccine in patients treated with B-cell depleting therapy.

OBJECTIVE: to investigate the responses to mRNA COVID-19 vaccines in a cohort of immunosuppressed patients affected by immune-mediated inflammatory diseases (IMID). METHODS: we have measured humoral and cellular immunity using quantitative IgG anti-SARS-CoV-2 Spike antibody (anti-S-IgG), neutralization assays and specific interferon-gamma (IFN-g) release assay (IGRA) before and after the third dose of BNT162b2. The response of those on anti-CD20 (n = 18) was then compared with healthy controls (HC, n = 18) and IMID naïve to anti-CD20 drugs (n = 13). RESULTS: a third BNT162b2 dose is highly immunogenic in IMID patients naïve to anti-CD20, as 100% of the subjects seroconverted compared to the 55% in anti-CD20. The rate of IGRA response was of 79% in anti-CD20, 50% in IMID naïve to anti-CD20, 100% in HC. Among those who have seroconverted, IMID patients had significantly reduced anti-S-IgG and neutralization titers compared to HC, whereas no significant difference was observed when comparing anti-CD20 and HC. Furthermore, 13% of anti-CD20 and 7.7% of IMID were simultaneously negative for both neutralizing antibodies and IGRA after three doses. CONCLUSION: these data draw attention to the immunogenicity of COVID-19 vaccination in treated IMID, taking specific groups into consideration for vaccination program.

Nasopharyngeal virome analysis of COVID-19 patients during three different waves in Campania region of Italy.

From December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has spread rapidly, leading to a global pandemic. Little is known about possible relationships between SARS-CoV-2 and other viruses in the respiratory system affecting patient prognosis and outcomes. This study aims to characterize respiratory virome profiles in association with SARS-CoV-2 infection and disease severity, through the analysis in 89 nasopharyngeal swabs collected in a patient's cohort from the Campania region (Southern Italy). Results show coinfections with viral species belonging to Coronaviridae, Retroviridae, Herpesviridae, Poxviridae, Pneumoviridae, Pandoraviridae, and Anelloviridae families and only 2% of the cases (2/89) identified respiratory viruses.

Synthesis and Antiproliferative Effect of Halogenated Coumarin Derivatives.

A series of 6- and 6,8-halocoumarin derivatives have been investigated as potential antiproliferative compounds against a panel of tumor and normal cell lines. Cytotoxic effects were determined by the MTT method. To investigate the potential molecular mechanism involved in the cytotoxic effect, apoptosis assay, cell cycle analysis, reactive oxygen species (ROS), and reduced glutathione analysis were performed. Among the screened compounds, coumarins 6,8-dibromo-2-oxo-2H-chromene-3-carbonitrile 2h and 6,8-diiodo-2-oxo-2H-chromene-3-carbonitrile 2k exhibited the most antiproliferative effect in thyroid cancer-derived cells TPC-1. The apoptosis assay showed that both 2h and 2k induced apoptosis in TPC-1 thyroid cancer cells. According to these experiments, both coumarins induced a slight increase in TPC-1 cells in the G2/M phase and a decrease in the S phase. A significant increase in ROS levels was observed in TPC-1 treated with diiodocoumarin 2k, while the dibromocoumarin 2h induced a decrease in ROS in a dose and time-dependent manner.

EFFECT: a randomized phase II study of efficacy and impact on function of two doses of nab-paclitaxel as first-line treatment in older women with advanced breast cancer.

BACKGROUND: Limited data are available regarding the use of nab-paclitaxel in older patients with breast cancer. A weekly schedule is recommended, but there is a paucity of evidence regarding the optimal dose. We evaluated the efficacy of two different doses of weekly nab-paclitaxel, with a specific focus on their corresponding impact on patient function, in order to address the lack of data specifically relating to the older population. METHODS: EFFECT is an open-label, phase II trial wherein 160 women with advanced breast cancer aged ≥ 65 years were enrolled from 15 institutions within Italy. Patients were randomly assigned 1:1 to receive nab-paclitaxel 100 mg/m2 (arm A) or 125 mg/m2 (arm B) on days 1, 8, and 15 on a 28-day cycle, as first-line treatment for advanced disease. The primary endpoint was event-free survival (EFS), wherein an event was defined as disease progression (PD), functional decline (FD), or death. In each arm, the null hypothesis that the median EFS would be ≤ 7 months was tested against a one-sided alternative according to the Brookmeyer Crowley test. Secondary endpoints included objective response rate (ORR), clinical benefit rate (CBR), progression-free survival (PFS), overall survival (OS), and safety. RESULTS: After a median follow-up of 32.6 months, 140 events were observed in 158 evaluable patients. Median EFS was 8.2 months (90% CI, 5.9-8.9; p = 0.188) in arm A vs 8.3 months (90% CI, 6.2-9.7, p = 0.078) in arm B. Progression-free survival, overall survival, and response rates were similar in both groups. A higher percentage of dose reductions and discontinuations due to adverse events (AEs) was noted in arm B. The most frequently reported non-haematological AEs were fatigue (grade [G] 2-3 toxicity occurrence in arm A vs B, 43% and 51%, respectively) and peripheral neuropathy (G2-3 arm A vs B, 19% and 38%, respectively). CONCLUSION: Pre-specified outcomes were similar in both treatment arms. However, 100 mg/m2 was significantly better tolerated with fewer neurotoxicity-related events, representing a more feasible dose to be recommended for older patients with advanced disease. TRIAL REGISTRATION: EudraCT, 2012-002707-18 . Registered on June 4, 2012. NIH ClinicalTrials.gov, NCT02783222 . Retrospectively registered on May 26, 2016.

Measles Virus Bearing Measles Inclusion Body Encephalitis-Derived Fusion Protein Is Pathogenic after Infection via the Respiratory Route.

A clinical isolate of measles virus (MeV) bearing a single amino acid alteration in the viral fusion protein (F; L454W) was previously identified in two patients with lethal sequelae of MeV central nervous system (CNS) infection. The mutation dysregulated the viral fusion machinery so that the mutated F protein mediated cell fusion in the absence of known MeV cellular receptors. While this virus could feasibly have arisen via intrahost evolution of the wild-type (wt) virus, it was recently shown that the same mutation emerged under the selective pressure of small-molecule antiviral treatment. Under these conditions, a potentially neuropathogenic variant emerged outside the CNS. While CNS adaptation of MeV was thought to generate viruses that are less fit for interhost spread, we show that two animal models can be readily infected with CNS-adapted MeV via the respiratory route. Despite bearing a fusion protein that is less stable at 37°C than the wt MeV F, this virus infects and replicates in cotton rat lung tissue more efficiently than the wt virus and is lethal in a suckling mouse model of MeV encephalitis even with a lower inoculum. Thus, either during lethal MeV CNS infection or during antiviral treatment in vitro, neuropathogenic MeV can emerge, can infect new hosts via the respiratory route, and is more pathogenic (at least in these animal models) than wt MeV.IMPORTANCE Measles virus (MeV) infection can be severe in immunocompromised individuals and lead to complications, including measles inclusion body encephalitis (MIBE). In some cases, MeV persistence and subacute sclerosing panencephalitis (SSPE) occur even in the face of an intact immune response. While they are relatively rare complications of MeV infection, MIBE and SSPE are lethal. This work addresses the hypothesis that despite a dysregulated viral fusion complex, central nervous system (CNS)-adapted measles virus can spread outside the CNS within an infected host.

Clinical outcomes after palbociclib with or without endocrine therapy in postmenopausal women with hormone receptor positive and HER2-negative metastatic breast cancer enrolled in the TREnd trial.

Currently, there is limited data regarding the effectiveness of standard subsequent line therapies such as endocrine therapy, chemotherapy, or targeted agents after progression on CDK4/6 inhibitor-based regimens. This paper describes time-to-treatment failure beyond progression on palbociclib or palbociclib+endocrine therapy in patients enrolled in the phase II, multicenter TREnd trial. Our results indicate that there is limited benefit from post-palbociclib treatment, regardless of the type of therapy received. A small population of long responders were identified who demonstrated ongoing benefit from a subsequent line of endocrine therapy after progression to palbociclib-based regimens. A translational research program is ongoing on this population of outliers.

Novel mutations in two unrelated Italian patients with SSADH deficiency.

Succinic semialdehyde dehydrogenase deficiency (SSADHD) is a rare autosomal recessive disorder of γ-aminobutyric acid (GABA) catabolism caused by mutations in the gene coding for succinic semialdehyde dehydrogenase (ALDH5A1). The abnormal levels of GHB detected in the brain and in all physiological fluids of SSADHD patients represent a diagnostic biochemical hallmark of the disease. Here we report on the clinical and molecular characterization of two unrelated Italian patients and the identification of two novel mutations: a 22 bp DNA duplication in exon 1, c.114_135dup, p.(C46AfsX97), and a non-sense mutation in exon 10, c.1429C > T, p.(Q477X). The two patients showed very different clinical phenotypes, coherent with their age. These findings enrich the characterization of SSADHD families and contribute to the knowledge on the progression of the disease.

Disubstituted 4-Chloro-3-nitrophenylthiourea Derivatives: Antimicrobial and Cytotoxic Studies.

4-Chloro-3-nitrophenylthioureas 1⁻30 were synthesized and tested for their antimicrobial and cytotoxic activities. Compounds exhibited high to moderate antistaphylococcal activity against both standard and clinical strains (MIC values 2⁻64 µg/mL). Among them derivatives with electron-donating alkyl substituents at the phenyl ring were the most promising. Moreover, compounds 1⁻6 and 8⁻19 were cytotoxic against MT-4 cells and various other cell lines derived from human hematological tumors (CC50 ≤ 10 µM). The influence of derivatives 11, 13 and 25 on viability, mortality and the growth rate of immortalized human keratinocytes (HaCaT) was observed.

Synthesis and Biological Evaluation of Novel Indole-Derived Thioureas.

A series of 2-(1H-indol-3-yl)ethylthiourea derivatives were prepared by condensation of 2-(1H-indol-3-yl)ethanamine with appropriate aryl/alkylisothiocyanates in anhydrous media. The structures of the newly synthesized compounds were confirmed by spectroscopic analysis and the molecular structures of 8 and 28 were confirmed by X-ray crystallography. All obtained compounds were tested for antimicrobial activity against Gram-positive cocci, Gram-negative rods and for antifungal activity. Microbiological evaluation was carried out over 20 standard strains and 30 hospital strains. Compound 6 showed significant inhibition against Gram-positive cocci and had inhibitory effect on the S. aureus topoisomerase IV decatenation activity and S. aureus DNA gyrase supercoiling activity. Compounds were tested for cytotoxicity and antiviral activity against a large panel of DNA and RNA viruses, including HIV-1 and other several important human pathogens. Interestingly, derivative 8 showed potent activity against HIV-1 wild type and variants bearing clinically relevant mutations. Newly synthesized tryptamine derivatives showed also a wide spectrum activity, proving to be active against positive- and negative-sense RNA viruses.

Free amino acids in fibromyalgia syndrome: relationship with clinical picture.

The objectives of our study were to evaluate free amino acid (FAA) concentrations in the serum of patients affected by fibromyalgia syndrome (FMS) and to determine the relationships between FAA levels and FMS clinical parameters. Thus, serum amino acid concentrations were quantified (HPLC analysis) in 23 females with fibromyalgia (according to the American College of Rheumatology classification criteria) and 20 healthy females. The results showed significantly higher serum concentrations of aspartate, cysteine, glutamate, glycine, isoleucine, leucine, methionine, ornithine, phenylalanine, sarcosine, serine, taurine, tyrosine and valine in FMS patients vs. healthy controls. Patients with higher Fibromyalgia Impact Questionnaire (FIQ) scores showed increased levels of alanine, glutamine, isoleucine, leucine, phenylalanine, proline and valine. In conclusion, our results indicate an imbalance in some FAAs in FMS patients. Increased Glu is particularly interesting, as it could explain the deficit in monoaminergic transmission involved in pain.

N-((1,3-Diphenyl-1H-pyrazol-4-yl)methyl)anilines: A novel class of anti-RSV agents.

A series of N-((1,3-diphenyl-1H-pyrazol-4-yl)methyl)anilines were synthesized and evaluated in vitro for cytotoxicity and antiviral activity against a large panel of viruses. Most of the tested compounds interfered with RSV replication in the micromolar concentrations (EC50s ranging from 5 µM to 28 µM). SAR studies suggested that the presence of a trifluoromethyl group in R(1) abolished the anti-RSV activity and enhanced the cytotoxicity while the best results in term of both anti-RSV activity and selectivity were obtained by the introduction in R(1) of a chlorine or a bromine atom.

Isolation and anticancer, anthelminthic, and antiviral (HIV) activity of acylphloroglucinols, and regioselective synthesis of empetrifranzinans from Hypericum roeperianum.

From the ethno-medicinally used leaves of Hypericum roeperianum we isolated a new tricyclic acylphloroglucinol (1), a new tetracyclic acylphloroglucinol (2), and a new prenylated bicyclic acylphloroglucinol (3) together with four known prenylated (4-7) and three known tetracyclic acylphloroglucinol derivatives (8-10). Structure elucidation was based on UV, IR, [α]D(25), 1D- and 2D-NMR experiments. Furthermore, empetrifranzinans A (8) and C (9) were synthesized regioselectively in only two steps. The isolated compounds were evaluated for their cytotoxicity against PC-3 and HT-29 cancer cell lines as well as antibacterial and anthelmintic activities. They were also tested in cell-based assays for cytotoxicity against MT-4 cells and for anti-HIV activity in infected MT-4 cells. Significant anthelmintic activity against Caenorhabditis elegans was exhibited by compound 7 (3-geranyl-1-(2'-methylbutanoyl)-phloroglucinol), which might provide a new lead.

Antimicrobial and anti-biofilm activity of thiourea derivatives incorporating a 2-aminothiazole scaffold.

A series of new thiourea derivatives of 1,3-thiazole have been synthesized. All obtained compounds were tested in vitro against a number of microorganisms, including Gram-positive cocci, Gram-negative rods and Candida albicans. Compounds were also tested for their in vitro tuberculostatic activity against the Mycobacterium tuberculosis H37Rv strain, as well as two 'wild' strains isolated from tuberculosis patients. Compounds 3 and 9 showed significant inhibition against Gram-positive cocci (standard strains and hospital strain). The range of MIC values is 2-32 µg/mL. Products 3 and 9 effectively inhibited the biofilm formation of both methicillin-resistant and standard strains of S. epidermidis. The halogen atom, especially at the 3rd position of the phenyl group, is significantly important for this antimicrobial activity. Moreover, all obtained compounds resulted in cytotoxicity and antiviral activity on a large set of DNA and RNA viruses, including Human Immunodeficiency Virus type 1 (HIV-1) and other several important human pathogens. Compound 4 showed activity against HIV-1 and Coxsackievirus type B5. Seven compounds resulted in cytotoxicity against MT-4 cells (CC50<10 µM).

Antiviral activity of benzimidazole derivatives. III. Novel anti-CVB-5, anti-RSV and anti-Sb-1 agents.

A library of eighty-six assorted benzimidazole derivatives was screened for antiviral activity against a panel of ten RNA and DNA viruses. Fifty-two of them displayed different levels of activity against one or more viruses, among which CVB-5, RSV, BVDV and Sb-1 were the most frequently affected. In particular, fourteen compounds exhibited an EC50 in the range 9-17µM (SI from 6 to >11) versus CVB-5, and seven compounds showed an EC50 in the range 5-15µM (SI from 6.7 to ⩾20) against RSV, thus resulting comparable to or more potent than the respective reference drugs (NM108 and ribavirin). Most of these compounds derive from 2-benzylbenzimidazole, but also other molecular scaffolds [as 1-phenylbenzimidazole (2), 2-trifluoromethylbenzimidazole (69), dihydropyrido[3',2':4,5]imidazo[1,2-a][1,4]benzodiazepin-5-one (3), dibenzo[c,e]benzimidazo[1,2-a]azepine (22), and 2-(tetrahydropyran-2-yl)benzimidazole (81, 82 and 86)] are related to interesting levels of activity against these or other viruses (BVDV, Sb-1). Thus, these scaffolds (some of which, so far unexplored), represent valid starting points to develop more efficient agents against pathologies caused by CVB-5, RSV, BVDV and Sb-1 viruses.

The Effect of Exposure to SARS-CoV-2 Vaccination and Infection on Humoral and Cellular Immunity in a Cohort of Patients with Immune-Mediated Diseases: A Pilot Study.

Immunization against COVID-19 is needed in patients with immune-mediated inflammatory diseases (IMIDs). However, data on long-term immunity kinetics remain scarce. This study aimed to compare the humoral and cellular response to COVID-19 in patients with immune-mediated inflammatory diseases (IMIDs) compared to healthy controls. We compared the humoral and cellular response to SARS-Cov-2 elicited by vaccination and/or infection in a prospective cohort of 20 IMID patients compared with a group of 21 healthcare workers (HCWs). We assessed immunity before and after the third and fourth dose of BNT162b2 or after COVID-19 infection using quantitative IgG anti-SARS-CoV-2 Spike antibody (anti-S-IgG), neutralization assay, and specific interferon-gamma (IFN-g) release assay (IGRA). The responses were compared with those of healthy controls. The two groups were similar in age and total exposure, becoming infected for the first time, mainly after the third dose. Neutralizing antibodies and IGRA were negative in 9.5% of IMID patients but not in any HCWs. No significant difference was found between neutralization titers to BA.1 in the IMID and the HCW groups. The study highlights the SARS-CoV-2 immunological responses in healthy controls and IMID patients, suggesting that the combined stimuli of vaccination and infection in IMID patients could promote a more profound immunological response.

Humoral responses to wild type and ancient BA.1 SARS-CoV-2 variant after heterologous priming vaccination with ChAdOx1 nCoV-19 and BNT162b2 booster dose.

Several countries have recommended a booster dose of Pfizer BNT162b2 vaccine for subjects under the age of 60, who have already received the first dose of ChAdOx1. This is due to several ChAdOx1 vaccine-associated adverse vascular events and thrombocytopenia. Neutralization assay and quantitative IgG anti-SARS-CoV-2 Spike antibody (anti-S-IgG) were conducted to investigate the long-term responses to vaccine treatment in a cohort of Sardinian participants, who have received heterologous Prime-Boost Vaccination via ChAdOx1 vector vaccine and a booster dose via BNT162b2. The obtained results were compared with those of a cohort of healthcare workers (HCW) who received homologous BNT162b2 (BNT/BNT/BNT) vaccination. One month (T2) and five months after the second and before the third dose (T3), anti-spike antibody or neutralizing titers in the subjects vaccinated with ChAdOx1-S/BNT162b2 were significantly higher than those who experienced the ChAdOx1-S/ChAdOx1-S or BNT162b2/BNT162b2 schedule. These results suggest that a ChAdOx1-S/BNT162b2 regimen provides a more robust antibody response than either of the homologous regimens. However, the anti-spike antibodies or neutralizing titers after the third injection (mRNA vaccine) of ChAdOx1-S as a second dose and BNT162b2 were not statistically different. Homologous and heterologous vaccination provided a strong antibody response. Neutralizing activities were also described against the Omicron BA.1 variant in a sub-group (40) representative of the three vaccination regimens among our cohort.

Exploring the Antiviral Potential of Esters of Cinnamic Acids with Quercetin.

Severe acute respiratory syndrome-related Coronavirus 2 (SARS-CoV-2) has infected more than 762 million people to date and has caused approximately 7 million deaths all around the world, involving more than 187 countries. Although currently available vaccines show high efficacy in preventing severe respiratory complications in infected patients, the high number of mutations in the S proteins of the current variants is responsible for the high level of immune evasion and transmissibility of the virus and the reduced effectiveness of acquired immunity. In this scenario, the development of safe and effective drugs of synthetic or natural origin to suppress viral replication and treat acute forms of COVID-19 remains a valid therapeutic challenge. Given the successful history of flavonoids-based drug discovery, we developed esters of substituted cinnamic acids with quercetin to evaluate their in vitro activity against a broad spectrum of Coronaviruses. Interestingly, two derivatives, the 3,4-methylenedioxy 6 and the ester of acid 7, have proved to be effective in reducing OC43-induced cytopathogenicity, showing interesting EC50s profiles. The ester of synaptic acid 7 in particular, which is not endowed with relevant cytotoxicity under any of the tested conditions, turned out to be active against OC43 and SARS-CoV-2, showing a promising EC50. Therefore, said compound was selected as the lead object of further analysis. When tested in a yield reduction, assay 7 produced a significant dose-dependent reduction in viral titer. However, the compound was not virucidal, as exposure to high concentrations of it did not affect viral infectivity, nor did it affect hCoV-OC43 penetration into pre-treated host cells. Additional studies on the action mechanism have suggested that our derivative may inhibit viral endocytosis by reducing viral attachment to host cells.