Neuroendocrine Small Cell Carcinoma of the Cervix: A case report

Merkel cell polyomavirus (MCPyV) has been found in patients with Merkel cell carcinoma and respiratory tract infections. Merkel cell carcinoma is a primary aggressive neuroendocrine carcinoma of the skin. It has been demonstrated that MCPyV can be transmitted during sexual activity and may be present in the oral and anogenital mucosa. The aim of the present study was to evaluate whether MCPyV coexisted with HPV in three cases of neuroendocrine small cell carcinoma of the cervix using PCR and immunohistochemical analysis Three cases of NSC of the cervix were identified in the pathology archives of Parma University (Italy). Of these, two cases were associated with an adenocarcinomatous component. A set of general primers from the L1 region (forward, L1C1 and reverse, L1C2 or L1C2M) was PCR amplified to detect the broad‑spectrum DNA of genital HPV. The presence of MCPyV was investigated via immunohistochemistry using a mouse monoclonal antibody against the MCPyV LT antigen and through PCR analysis to separate viral DNA. HPV DNA was present in all three neuroendocrine carcinomas and in the adenocarcinoma component of the two mixed cases. None of the cases were immunoreactive to CM2B4 and did not contain viral DNA in either their neuroendocrine or adenocarcinomatous component. Whilst it is difficult to draw definitive conclusions from such a small sample size, these data suggested that MCPyV does not coexist with HPV in the cervix. However, in the present study, the absence of detectable MCPyV may have been due to the presence of a genotype that was not detected by the primers used in the PCR analysis or by the antibody used for the immunohistochemical study. MCPyV microRNA may also have been present, inhibiting LT expression. Additional studies with larger cohorts and more advanced molecular biology techniques are required to confirm the hypothesis of the current study

COVID-19-associated Guillain-Barré syndrome in the early pandemic experience in Lombardia (Italy)

Objective To estimate the incidence and describe clinical characteristics and outcome of GBS in COVID-19 patients (COVID19-GBS) in one of the most hit regions during the frst pandemic wave, Lombardia. Methods Adult patients admitted to 20 Neurological Units between 1/3–30/4/2020 with COVID19-GBS were included as part of a multi-center study organized by the Italian society of Hospital Neuroscience (SNO). Results Thirty-eight COVID19-GBS patients had a mean age of 60.7 years and male frequency of 86.8%. CSF albuminocytological dissociation was detected in 71.4%, and PCR for SARS-CoV-2 was negative in 19 tested patients. Based on neurophysiology, 81.8% of patients had a diagnosis of AIDP, 12.1% of AMSAN, and 6.1% of AMAN. The course was favorable in 76.3% of patients, stable in 10.5%, while 13.2% worsened, of which 3 died. The estimated occurrence rate in Lombardia ranges from 0.5 to 0.05 GBS cases per 1000 COVID-19 infections depending on whether you consider positive cases or estimated seropositive cases. When we compared GBS cases with the pre-pandemic period, we found a reduction of cases from 165 to 135 cases in the 2-month study period in Lombardia. Conclusions We detected an increased incidence of GBS in COVID-19 patients which can refect a higher risk of GBS in COVID-19 patients and a reduction of GBS events during the pandemic period possibly due to a lower spread of more common respiratory infectious diseases determined by an increased use of preventive measures

Microsatellite analysis of rare serous tumours of the fallopian tubes comparison with serous ovarian neoplasms

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Antifungal activity of the C-terminal peptide from human serum albumin

Introduction In recent years, a number of studies showed the biological activities of peptides derived by proteolytic cleavage of physiological proteins. These functional units, called cryptides, can be characterized by activities similar or different to those of the precursor protein. The present study was aimed to evaluate the fungicidal properties of a synthetic peptide (K13L, KKLVAASQAALGL), representing the C-terminal fragment of human albumin found in serum. Materials and Methods The synthetic peptide was obtained by solid-phase synthesis chemistry and evaluated for its biological properties by consolidated experimental methods. The in vitro fungicidal activity was investigated against different yeast species, inclusive of multidrug resistant strains. The ex vivo and in vivo anticandidal efficacy was evaluated in a model of C. albicans infection in porcine oral mucosa and in experimentally infected larvae of Galleria mellonella, respectively. Furthermore, haemolytic, cytotoxic and genotoxic properties were verified. The effect of peptide treatment on C. albicans cells was studied by confocal microscopy and transmission and scanning electron microscopy. Results K13L peptide proved to be fungicidal in vitro against the investigated yeasts at micromolar concentrations, to reduce fungal infiltration in porcine oral mucosa ex vivo, and to exert a therapeutic effect in vivo in the invertebrate animal model, without showing toxic effects on mammalian cells. Microscopic studies demonstrated that the peptide penetrates and accumulates in fungal cells causing gross morphological alterations in cellular structure. Conclusions Overall, our data prove that fragments from physiological serum proteins, as K13L peptide, may exert an antifungal activity, as previously shown for antibody-derived peptides, suggesting a potential role of these molecules in antifungal homeostasis and establishing serum proteins as a source of new antimicrobial agents

Fungicidal activity of peptides encoded by immunoglobulin genes

Abstract Evidence from previous works disclosed the antimicrobial, antiviral, anti-tumour and/or immunomodulatory activity exerted, through different mechanisms of action, by peptides expressed in the complementarity-determining regions or even in the constant region of antibodies, independently from their specificity and isotype. Presently, we report the selection, from available databases, of peptide sequences encoded by immunoglobulin genes for the evaluation of their potential biological activities. Synthetic peptides representing the translated products of J lambda and J heavy genes proved to act in vitro against pathogenic fungi, entering yeast cells and causing their death, and exerted a therapeutic effect in a Galleria mellonella model of infection by Candida albicans. No haemolytic, cytotoxic and genotoxic effects were observed on mammalian cells. These findings raise the hypothesis that antibodies could be the evolutionary result of the adaptive combination of gene products ancestrally devoted to innate antimicrobial immunity

In Vitro and In Vivo Anti-<i>Candida</i> Activity and Structural Analysis of Killer Peptide (KP)-Derivatives

The previously described decapeptide AKVTMTCSAS (killer peptide, KP), derived from the variable region of a recombinant yeast killer toxin-like anti-idiotypic antibody, proved to exert a variety of antimicrobial, antiviral, and immunomodulatory activities. It also showed a peculiar self-assembly ability, likely responsible for the therapeutic effect in animal models of systemic and mucosal candidiasis. The present study analyzed the biological and structural properties of peptides derived from KP by substitution or deletion of the first residue, leaving unchanged the remaining amino acids. The investigated peptides proved to exert differential in vitro and/or in vivo anti-Candida activity without showing toxic effects on mammalian cells. The change of the first residue in KP amino acidic sequence affected the conformation of the resulting peptides in solution, as assessed by circular dichroism spectroscopy. KP-derivatives, except one, were able to induce apoptosis in yeast cells, like KP itself. ROS production and changes in mitochondrial transmembrane potential were also observed. Confocal and transmission electron microscopy studies allowed to establish that selected peptides could penetrate within C. albicans cells and cause gross morphological alterations. Overall, the physical and chemical properties of the first residue were found to be important for peptide conformation, candidacidal activity and possible mechanism of action. Small antimicrobial peptides could be exploited for the development of a new generation of antifungal drugs, given their relative low cost and ease of production as well as the possibility of devising novel delivery systems

Relazione struttura-funzione di un peptide fungicida derivato dalla regione costante di immunoglobuline G umane

Peptidi sintetici corrispondenti alle sequenze delle regioni determinanti la complementarità o derivati dalla regione costante di anticorpi hanno dimostrato di esercitare in vitro, ex vivo e/o in vivo un’attività differenziale, antimicrobica, antivirale, antitumorale e/o immunomodulatoria, indipendentemente dalla specificità e dall’isotipo dell’anticorpo parentale. Derivati degli stessi peptidi, ottenuti mediante sostituzione di ciascun residuo con alanina, hanno mostrato un’attività candidacida in vitro inalterata, aumentata o diminuita. Il peptide bioattivo N10K, la cui sequenza (NQVSLTCLVK) è presente nella regione costante delle IgG umane, ha mostrato la capacità di auto-aggregare in modo spontaneo in strutture β, caratteristica precedentemente riconosciuta come rilevante per l’attività terapeutica di un altro peptide di derivazione anticorpale. Il contributo di ciascun residuo all’auto-aggregazione è stato analizzato mediante dicroismo circolare. L’interazione di N10K e di suoi derivati con cellule di Candida albicans è stata studiata in microscopia confocale ed elettronica, a trasmissione e a scansione. I profili di induzione di apoptosi e autofagia in cellule di lievito trattate con i peptidi sono stati valutati mediante citometria a flusso, mentre l’efficacia terapeutica è stata studiata in un modello di candidosi sistemica sperimentale in Galleria mellonella. Complessivamente, i risultati indicano il ruolo critico di alcuni residui nel processo di auto-aggregazione dei peptidi e una correlazione di tale capacità con l’effetto terapeutico in vivo

Novel Activity of a Synthetic Decapeptide Against Toxoplasma gondii Tachyzoites

The killer peptide KP is a synthetic decapeptide derived from the sequence of the variable region of a recombinant yeast killer toxin-like microbicidal single-chain antibody. KP proved to exert significant activities against diverse microbial and viral pathogens through different mechanisms of action, but little is known of its effect on apicomplexan protozoa. The aim of the present study was to evaluate the in vitro activity of KP against Toxoplasma gondii, a globally widespread protozoan parasite of great medical interest. The effect of KP treatment and its potential mechanism of action on T. gondii were evaluated by various methods, including light microscopy, quantitative PCR, flow cytometry, confocal microscopy, and transmission electron microscopy. In the presence of KP, the number of T. gondii tachyzoites able to invade Vero cells and the parasite intracellular proliferation were significantly reduced. Morphological observation and analysis of apoptotic markers suggested that KP is able to trigger an apoptosis-like cell death in T. gondii. Overall, our results indicate that KP could be a promising candidate for the development of new anti-Toxoplasma drugs with a novel mechanism of action

Adenomatous polyposis coli gene involvement in ileal enterochromaffin cell neuroendocrine neoplasms

The adenomatous polyposis coli gene is a key tumor suppressor gene. Alterations in this gene have been found in most sporadic colon cancers; associated with familial adenomatous polyposis; and found in neoplasms of other organs, such as the liver, stomach, lung, breast, and cerebellar medulloblastoma. In the heterogeneous group of neuroendocrine neoplasms of the gastrointestinal tract, the involvement of adenomatous polyposis coli is debated, and only occasional reports found adenomatous polyposis coli alterations in foregut and midgut neuroendocrine neoplasms, with adenomatous polyposis coli mutations only in the latter. To elucidate the penetrance of adenomatous polyposis coli alterations in ileal neuroendocrine neoplasms, we performed DNA fragment analysis (loss of heterozygosity for 5q22-23 and 5q23) and sequencing on the mutation cluster region of the adenomatous polyposis coli gene on 30 ileal enterochromaffin cell neuroendocrine neoplasms. Adenomatous polyposis coli gene mutations were detected in 23% of cases (7/30); in particular, 57% were missense and 14%, nonsense/frameshift, all novel and different from those reported in colorectal or other cancers. Loss of heterozygosity analysis demonstrated a deletion frequency of 15% (4/27). No association was found with features of tumor progression. Our observations support the involvement of somatic adenomatous polyposis coli alterations in tumorigenesis of ileal enterochromaffin cell neuroendocrine neoplasms; the mechanisms of adenomatous polyposis coli gene inactivation appear to be different from those reported in other tumor types