One-step silver coating of polypropylene surgical mask with antibacterial and antiviral properties.

Face masks can filter droplets containing viruses and bacteria minimizing the transmission and spread of respiratory pathogens but are also an indirect source of microbes transmission. A novel antibacterial and antiviral Ag-coated polypropylene surgical mask obtained through the in situ and one-step deposition of metallic silver nanoparticles, synthesized by silver mirror reaction combined with sonication or agitation methods, is proposed in this study. SEM analysis shows Ag nanoparticles fused together in a continuous and dense layer for the coating obtained by sonication, whereas individual Ag nanoparticles around 150 nm were obtained combining the silver mirror reaction with agitation. EDX, XRD and XPS confirm the presence of metallic Ag in both coatings and also oxidized Ag in samples by agitation. A higher amount of Ag nanoparticles is deposited on samples by sonication, as calculated by TGA. Further, both coatings are biocompatible and show antibacterial properties: coating by sonication caused 24 % and 40 % of bacterial reduction while coating by agitation 48 % and 96 % against S. aureus and E. coli, respectively. At 1 min of contact with SARS-CoV-2, the coating by agitation has an antiviral capacity of 75 % against 24 % of the one by sonication. At 1 h, both coatings achieve 100 % of viral inhibition. Nonetheless, larger samples could be produced only through the silver mirror reaction combined with agitation, preserving the integrity of the mask. In conclusion, the silver-coated mask produced by silver mirror reaction combined with agitation is scalable, has excellent physico-chemical characteristics as well as significant biological properties, with higher antimicrobial activities, providing additional protection and preventing the indirect transmission of pathogens.

Melanocortin receptor 4 as a new target in melanoma therapy: Anticancer activity of the inhibitor ML00253764 alone and in association with B-raf inhibitor vemurafenib.

The aim of our study is to investigate in vitro and in vivo MC4R as a novel target in melanoma using the selective antagonist ML00253764 (ML) alone and in combination with vemurafenib, a B-rafV600E inhibitor. The human melanoma B-raf mutated A-2058 and WM 266-4 cell lines were used. An MC4R null A-2058 cell line was generated using a CRISPR/Cas9 system. MC4R protein expression was analysed by western blotting, immunohistochemistry, and immunofluorescence. Proliferation and apoptotic assays were performed with ML00253764, whereas the synergism with vemurafenib was evaluated by the combination index (CI) and Loewe methods. ERK1/2 phosphorylation and BCL-XL expression were quantified by western blot. In vivo experiments were performed in Athymic Nude-Foxn1nu male mice, injecting subcutaneously melanoma cells, and treating animals with ML, vemurafenib and their concomitant combination. Comet and cytome assays were performed. Our results show that human melanoma cell lines A-2058 and WM 266-4, and melanoma human tissue, express functional MC4R receptors on their surface. MC4R receptors on melanoma cells can be inhibited by the selective antagonist ML, causing antiproliferative and proapoptotic activity through the inhibition of phosphorylation of ERK1/2 and a reduction of BCL-XL. The concomitant combination of vemurafenib and ML caused a synergistic effect on melanoma cells in vitro and inhibited in vivo tumor growth in a preclinical model, without causing mouse weight loss or genotoxicity. Our original research contributes to the landscape of pharmacological treatments for melanoma, providing MC4R antagonists as drugs that can be added to established therapies.

Human T-Cell Leukemia Virus Type 1 Oncogenesis between Active Expression and Latency: A Possible Source for the Development of Therapeutic Targets.

The human T-cell leukemia virus type 1 (HTLV-1) is the only known human oncogenic retrovirus. HTLV-1 can cause a type of cancer called adult T-cell leukemia/lymphoma (ATL). The virus is transmitted through the body fluids of infected individuals, primarily breast milk, blood, and semen. At least 5-10 million people in the world are infected with HTLV-1. In addition to ATL, HTLV-1 infection can also cause HTLV-I-associated myelopathy (HAM/TSP). ATL is characterized by a low viral expression and poor prognosis. The oncogenic mechanism triggered by HTLV-1 is extremely complex and the molecular pathways are not fully understood. However, viral regulatory proteins Tax and HTLV-1 bZIP factor (HBZ) have been shown to play key roles in the transformation of HTLV-1-infected T cells. Moreover, several studies have shown that the final fate of HTLV-1-infected transformed Tcell clones is the result of a complex interplay of HTLV-1 oncogenic protein expression with cellular transcription factors that subvert the cell cycle and disrupt regulated cell death, thereby exerting their transforming effects. This review provides updated information on the mechanisms underlying the transforming action of HTLV-1 and highlights potential therapeutic targets to combat ATL.

Severe acute respiratory syndrome coronavirus 2 infection leads to Tau pathological signature in neurons.

COVID-19 has represented an issue for global health since its outbreak in March 2020. It is now evident that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection results in a wide range of long-term neurological symptoms and is worryingly associated with the aggravation of Alzheimer's disease. Little is known about the molecular basis of these manifestations. Here, several strain variants were used to infect SH-SY5Y neuroblastoma cells and K18-hACE C57BL/6J mice. The Tau phosphorylation profile and aggregation propensity upon infection were investigated on cellular extracts, subcellular fractions, and brain tissue. The viral proteins spike, nucleocapsid, and membrane were overexpressed in SH-SY5Y cells, and the direct interaction and effect on Tau phosphorylation were checked using immunoblot experiments. Upon infection, Tau is phosphorylated at several pathological epitopes associated with Alzheimer's disease and other tauopathies. Moreover, this event increases Tau's propensity to form insoluble aggregates and alters its subcellular localization. Our data support the hypothesis that SARS-CoV-2 infection in the central nervous system triggers downstream effects altering Tau function, eventually leading to the impairment of neuronal function.

Exploring the link between viruses and cancer in companion animals: a comprehensive and comparative analysis.

Currently, it is estimated that 15% of human neoplasms globally are caused by infectious agents, with new evidence emerging continuously. Multiple agents have been implicated in various forms of neoplasia, with viruses as the most frequent. In recent years, investigation on viral mechanisms underlying tumoral transformation in cancer development and progression are in the spotlight, both in human and veterinary oncology. Oncogenic viruses in veterinary medicine are of primary importance not only as original pathogens of pets, but also in the view of pets as models of human malignancies. Hence, this work will provide an overview of the main oncogenic viruses of companion animals, with brief notes of comparative medicine.

Canonical fibroblast growth factors in viral infection.

Fibroblast growth factors (FGFs) are a family of proteins that play a crucial role in the development and maintenance of various tissues in the body. There are three function-al groups of FGFs: canonical FGFs (cFGFs), intracellularly retained FGFs, and metabolic (also called endocrine) FGFs. cFGFs are secreted and act in an autocrine/paracrine fashion to regulate differentiation during foetal development, as well as tissue repair in adults. Recent studies have also begun to unravel the role of cFGFs during viral infections, suggesting that FGF-2 and other canonical FGFs may have an important virus-specific role, also by the regulation of the immune response. Because dysregulation in the FGF pathways is pivotal in cancer development, FGFs are the target of many anticancer drugs. These drugs may be repurposed to treat viral infection, since dysregulation of FGF signalling has been implicated in the pathogenesis of viral infections, such as hepatitis C. Overall, the role of cFGFs during viral infection is an underrepresented area of current research. This review focuses on overviewing the effects of canonical FGFs during infection by different viruses. Many studies highlight that the effects of FGFs during viral infection may be complex and context-dependent. While there is evidence to suggest that FGFs may have a beneficial impact on the immune response and tissue repair during viral infection, further studies are needed to fully understand the mechanisms underlying these effects and to determine in what cases FGFs could be targeted as a therapeutic approach for viral infection.

Zika virus induces FOXG1 nuclear displacement and downregulation in human neural progenitors.

Congenital alterations in the levels of the transcription factor Forkhead box g1 (FOXG1) coding gene trigger "FOXG1 syndrome," a spectrum that recapitulates birth defects found in the "congenital Zika syndrome," such as microcephaly and other neurodevelopmental conditions. Here, we report that Zika virus (ZIKV) infection alters FOXG1 nuclear localization and causes its downregulation, thus impairing expression of genes involved in cell replication and apoptosis in several cell models, including human neural progenitor cells. Growth factors, such as EGF and FGF2, and Thr271 residue located in FOXG1 AKT domain, take part in the nuclear displacement and apoptosis protection, respectively. Finally, by progressive deletion of FOXG1 sequence, we identify the C-terminus and the residues 428-481 as critical domains. Collectively, our data suggest a causal mechanism by which ZIKV affects FOXG1, its target genes, cell cycle progression, and survival of human neural progenitors, thus contributing to microcephaly.

Presence of a mouse mammary tumour virus-like in feline lymphomas: a preliminary study.

The mouse mammary tumour virus (MMTV) is implicated in the aetiology of murine mammary carcinomas and a variant of it, the type B leukemogenic virus, can cause murine thymic lymphomas. Interestingly, a MMTV-like virus is suspected to be involved in human breast cancer and feline mammary carcinomas. However, to date, no cases of MMTV-like sequence amplifications have been described in lymphoid neoplasms in veterinary literature. The aim of this study was to investigate the presence of env nucleotide sequences and protein 14 (p14) of a MMTV-like virus in fifty-three feline lymphoma samples. Our results show that MMTV-like sequences were detected in 5/53 tumours (9.4%): three gastrointestinal lymphomas (one B-type diffuse large, one B-type small non-cleaved, and one T-type diffuse mixed lymphoma); and two nasal lymphomas (one B-type diffuse small cleaved lymphoma and one B-type diffuse mixed lymphoma). P14 expression was detected in the cytoplasm, and rarely in nuclei, exclusively of neoplastic cells from PCR-positive tumours. The correlation between the presence of the MMTV-env like sequences (MMTVels) and p14 antigen was statistically significant in nasal lymphomas. All cats with MMTVels-positive lymphoma had a history of contact with the outdoor environment and/or catteries, and two deceased subjects shared their environment with cats that also died of lymphoma. In conclusion, this study succeeds in demonstrating the presence of MMTVels and p14 in feline lymphomas. The characterization of the immunophenotype of MMTVels-positive lymphomas could contribute to the understanding of a possible role of a MMTV-like virus in feline tumour aetiology. The significant association between the presence of the viral sequences in lymphoid tumours and their nasal localization, together with the data collected through supplementary anamnesis, should be further analysed in order to understand the epidemiology of the virus.

Mouse Mammary Tumor Virus (MMTV) and MMTV-like Viruses: An In-depth Look at a Controversial Issue.

Since its discovery as a milk factor, mouse mammary tumor virus (MMTV) has been shown to cause mammary carcinoma and lymphoma in mice. MMTV infection depends upon a viral superantigen (sag)-induced immune response and exploits the immune system to establish infection in mammary epithelial cells when they actively divide. Simultaneously, it avoids immune responses, causing tumors through insertional mutagenesis and clonal expansion. Early studies identified antigens and sequences belonging to a virus homologous to MMTV in human samples. Several pieces of evidence fulfill a criterion for a possible causal role for the MMTV-like virus in human breast cancer (BC), though the controversy about whether this virus was linked to BC has raged for over 40 years in the literature. In this review, the most important issues related to MMTV, from its discovery to the present days, are retraced to fully explore such a controversial issue. Furthermore, the hypothesis of an MMTV-like virus raised the question of a potential zoonotic mouse-man transmission. Several studies investigate the role of an MMTV-like virus in companion animals, suggesting their possible role as mediators. Finally, the possibility of an MMTV-like virus as a cause of human BC opens a new era for prevention and therapy.

Positive peritoneal swab in SARS-CoV-2 patients undergoing abdominal emergency surgery: effect or cause?

PURPOSE: The presence of the SARS-CoV-2 in the peritoneal fluid is a matter of debate in the COVID-19 literature. The study aimed to report the prevalence of SARS-CoV-2 in the peritoneal fluid of patients with nasopharyngeal swab tested positive for SARS-CoV-2 undergoing emergency surgery and review the literature. METHODS: The present study was conducted between March 2020 and June 2021. Diagnosis of SARS-CoV-2 positivity was confirmed by preoperative real-time reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: Eighteen patients with positive nasopharyngeal swabs were operated in emergency in two third-level Italian hospitals. In 13 of these patients (72%), a peritoneal swab was analyzed: SARS-CoV-2 RNA was found in the abdominal fluid of two patients (15%). Neither of them had visceral perforation and one patient died. In ten patients with negative peritoneal swabs, visceral perforation and mortality rates were 30% and 20%, respectively. CONCLUSION: SARS-CoV-2 peritoneal positivity is rare. Abdominal surgery can, therefore, be safely performed in patients with COVID-19 using standard precautions. The correlation with a visceral perforation is not evaluable. The clinical outcomes seem uninfluenced by the viral colonization of the peritoneum. Assessment in large series to provide definitive answers about the involvement of the SARS-CoV-2 in the peritoneum will be challenging to coordinate.

Patterns of neutralizing humoral response to SARS-CoV-2 infection among hematologic malignancy patients reveal a robust immune response in anti-cancer therapy-naive patients.

Understanding antibody-based SARS-CoV-2 immunity in hematologic malignancy (HM) patients following infection is crucial to inform vaccination strategies for this highly vulnerable population. This cross-sectional study documents the anti-SARS-CoV-2 humoral response and serum neutralizing activity in 189 HM patients recovering from a PCR-confirmed infection. The overall seroconversion rate was 85.7%, with the lowest values in patients with lymphoid malignancies or undergoing chemotherapy. Therapy-naive patients in the "watch and wait" status were more likely to seroconvert and display increased anti-s IgG titers. Enhanced serum neutralizing activity was observed in the following SARS-CoV-2-infected HM patient groups: (i) males; (ii) severe COVID-19; and (iii) "watch and wait" or "complete/partial response". The geometric mean (GeoMean) ID50 neutralization titers in patients analyzed before or after 6 months post-infection were 299.1 and 306.3, respectively, indicating that >50% of the patients in either group had a neutralization titer sufficient to provide 50% protection from symptomatic COVID-19. Altogether, our findings suggest that therapy-naive HM patients mount a far more robust immune response to SARS-CoV-2 infection vs. patients receiving anti-cancer treatment, raising the important question as to whether HM patients should be vaccinated before therapy and/or receive vaccine formats capable of better recapitulating the natural infection.

Ictogenesis of viral pneumonia: A comparison between SARS-CoV-2 and H1N1/H3N2.

Several studies reported acute symptomatic seizures as a possible neurological complication of COVID-19 pneumonia. Apart from metabolic imbalances, hypoxia, and fever, other ictogenic mechanisms are likely related to an immune-mediated damage. The same mechanisms are shared by other respiratory viruses. Since neurotropic properties of SARS-CoV-2 have been questioned, we investigated whether SARS-CoV-2 has a similar ictogenic potential to other respiratory non-neurotropic viruses. We conducted a retrospective study identifying 1141 patients with SARS-CoV-2 pneumonia and 146 patients with H1N1/H3N2 pneumonia. We found a similar prevalence of seizures in the two viral pneumonia (1.05% with SARS-CoV-2 vs 2.05% with influenza; p = 0.26). We detailed clinical, electroencephalographic, and neuroradiological features of each patient, together with the hypothesized pathogenesis of seizures. Previous epilepsy or pre-existing predisposing conditions (i.e., Alzheimer's disease, stroke, cerebral neoplasia) were found in one-third of patients that experienced seizures, while two-thirds of patients had seizures without known risk factors other than pneumonia in both groups. The prevalence of pre-existing predisposing conditions and disease severity indexes was similar in SARS-CoV-2 and H1N1/H3N2 pneumonia, thus excluding they could act as potential confounders. Considering all the patients with viral pneumonia together, previous epilepsy (p < 0.001) and the need for ventilatory support (p < 0.001), but not the presence of pre-existing predisposing conditions (p = 0.290), were associated with seizure risk. Our study showed that SARS-CoV-2 and influenza viruses share a similar ictogenic potential. In both these infections, seizures are rare but serious events, and can manifest without pre-existing predisposing conditions, in particular when pneumonia is severe, thus suggesting an interplay between disease severity and host response as a major mechanism of ictogenesis, rather than a virus-specific mechanism.

Pathological Features and Molecular Phenotype of MMTV Like-Positive Feline Mammary Carcinomas.

In the last few years MMTV-like nucleotide sequences were detected in some feline and canine mammary tumours. Due to the confirmed role of cats in the epidemiology of the MMTV-like virus, the aim of this study was to investigate the main pathological features of positive feline mammary carcinomas (FMCs). Twenty-four FMCs were collected at the University of Bologna, submitted to laser microdissection and analysed by nested fluorescence-PCR using primer sets specific for MMTV env sequence. For immunohistochemistry, an antibody against MMTV protein 14 (p14) was used. MMTV-like sequences were detected in three out of 24 FMCs (12.5%), one tubular carcinoma, one tubulopapillary carcinoma and one ductal carcinoma. All PCR-positive tumours were also positive for p14. Multiple nucleotide alignment has shown similarity to MMTV ranging from 98% to 100%. All the 102 examined FMCs were submitted to immunohistochemistry for molecular phenotyping. Of the nine MMTV-like positive FMCs, six were basal-like and three luminal-like. Our results demonstrate MMTV-like sequences and protein in FMCs of different geographic areas. Molecular phenotyping could contribute to understand the possible role of MMTV-like virus in FMC tumor biology.

A pandemic recap: lessons we have learned.

On January 2020, the WHO Director General declared that the outbreak constitutes a Public Health Emergency of International Concern. The world has faced a worldwide spread crisis and is still dealing with it. The present paper represents a white paper concerning the tough lessons we have learned from the COVID-19 pandemic. Thus, an international and heterogenous multidisciplinary panel of very differentiated people would like to share global experiences and lessons with all interested and especially those responsible for future healthcare decision making. With the present paper, international and heterogenous multidisciplinary panel of very differentiated people would like to share global experiences and lessons with all interested and especially those responsible for future healthcare decision making.

Acid ceramidase controls apoptosis and increases autophagy in human melanoma cells treated with doxorubicin.

Acid ceramidase (AC) is a lysosomal hydrolase encoded by the ASAH1 gene, which cleaves ceramides into sphingosine and fatty acid. AC is expressed at high levels in most human melanoma cell lines and may confer resistance against chemotherapeutic agents. One such agent, doxorubicin, was shown to increase ceramide levels in melanoma cells. Ceramides contribute to the regulation of autophagy and apoptosis. Here we investigated the impact of AC ablation via CRISPR-Cas9 gene editing on the response of A375 melanoma cells to doxorubicin. We found that doxorubicin activates the autophagic response in wild-type A375 cells, which effectively resist apoptotic cell death. In striking contrast, doxorubicin fails to stimulate autophagy in A375 AC-null cells, which rapidly undergo apoptosis when exposed to the drug. The present work highlights changes that affect melanoma cells during incubation with doxorubicin, in A375 melanoma cells lacking AC. We found that the remarkable reduction in recovery rate after doxorubicin treatment is strictly associated with the impairment of autophagy, that forces the AC-inhibited cells into apoptotic path.

Nicotine upregulates ACE2 expression and increases competence for SARS-CoV-2 in human pneumocytes.

The coronavirus disease 2019 (COVID-19) pandemic has a variable degree of severity according to underlying comorbidities and life-style. Several research groups have reported an association between cigarette smoking and increased severity of COVID-19. The exact mechanism of action is largely unclear. We exposed low angiotensin-converting enzyme 2 (ACE2)-expressing human pulmonary adenocarcinoma A549 epithelial cells to nicotine and assessed ACE2 expression at different times. We further used the nicotine-exposed cells in a virus neutralisation assay. Nicotine exposure induces rapid and long-lasting increases in gene and protein expression of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor ACE2, which in turn translates into increased competence for SARS-CoV-2 replication and cytopathic effect. These findings show that nicotine worsens SARS-CoV-2 pulmonary infection and have implications for public health policies.

Ablation of Acid Ceramidase Impairs Autophagy and Mitochondria Activity in Melanoma Cells.

Cutaneous melanoma is often resistant to therapy due to its high plasticity, as well as its ability to metabolise chemotherapeutic drugs. Sphingolipid signalling plays a pivotal role in its progression and metastasis. One of the ways melanoma alters sphingolipid rheostat is via over-expression of lysosomal acid ceramidase (AC), which catalyses the hydrolysis of pro-apoptotic long-chain ceramides into sphingosine and fatty acid. In this report, we examine the role of acid ceramidase in maintaining cellular homeostasis through the regulation of autophagy and mitochondrial activity in melanoma cell lines. We show that under baseline conditions, wild-type melanoma cells had 3-fold higher levels of the autophagy marker, microtubule-associated proteins 1A/1B light chain 3B (LC3 II), compared to AC-null cells. This difference was further magnified after cell starvation. Moreover, we noticed autophagy impairment in A375 AC-null cells, possibly due to local accumulation of non-metabolized ceramides. Nonetheless, we observed that AC-null cells exhibited a significant increase in mitochondrial membrane potential compared to control cells. Consistent with this observation, we found that, after total starvation, ~30% of AC-null cells undergo apoptosis compared to ~6% of wild-type cells. As expected, AC transfection restored viability in A375 AC-null cells. Together, these findings suggest that AC-null melanoma cells change and adapt their metabolism to survive in the absence of AC, although in a way that does not allow them to cope with the stress of nutrient deprivation.

Protopine/Gemcitabine Combination Induces Cytotoxic or Cytoprotective Effects in Cell Type-Specific and Dose-Dependent Manner on Human Cancer and Normal Cells.

The natural alkaloid protopine (PRO) exhibits pharmacological properties including anticancer activity. We investigated the effects of PRO, alone and in combination with the chemotherapeutic gemcitabine (GEM), on human tumor cell lines and non-tumor human dermal fibroblasts (HDFs). We found that treatments with different PRO/GEM combinations were cytotoxic or cytoprotective, depending on concentration and cell type. PRO/GEM decreased viability in pancreatic cancer MIA PaCa-2 and PANC-1 cells, while it rescued the GEM-induced viability decline in HDFs and in tumor MCF-7 cells. Moreover, PRO/GEM decreased G1, S and G2/M phases, concomitantly with an increase of subG1 phase in MIA PaCa-2 and PANC-1 cells. Differently, PRO/GEM restored the normal progression of the cell cycle, altered by GEM, and decreased cell death in HDFs. PRO alone increased mitochondrial reactive oxygen species (ROS) in MIA PaCa-2, PANC-1 cells and HDFs, while PRO/GEM increased both intracellular and mitochondrial ROS in the three cell lines. These results indicate that specific combinations of PRO/GEM may be used to induce cytotoxic effects in pancreatic tumor MIA PaCa-2 and PANC-1 cells, but have cytoprotective or no effects in HDFs.