Clostridium perfringens-induced massive hemolysis treatment with blood purification to target toxins: a case report.

Clostridium perfringens can rarely cause severe systemic infections, usually from an abdominal source, associated with massive hemolysis, which is usually fatal. Hemolytic anemia and acute renal injury resulting from toxin action are critical for the development of multiple organ dysfunction syndrome (MODs), making this condition a real emergency, requiring multispecialty skills and aggressive multimodal therapies. We herein describe a case of septic shock from acute cholecystitis with massive hemolysis caused by C. perfringens in a 55 year-old man that was successfully treated with early blood purification and continuous renal replacement therapy (CRRT) along with antibiotic therapy and surgery. The effect of the enormous amount of toxins produced by Clostridium which elicit a strong cytokine response and the damage caused by the hemolysis products are the main pathogenetic mechanisms of this rare but lethal clinical entity. The main goal of treatment is to remove toxins from plasma, block toxin action, and further production by achieving bacterial killing with antimicrobial agents and controlling the infectious focus, remove waste products and prevent or limit multiorgan damage. Blood purification techniques play an important role due to a strong pathophysiological rationale, as they can remove toxins and cytokines as well as cell-free products from plasma and also replace renal function. Although this condition is rare and robust data are lacking, blood purification techniques for C. perfringens-induced massive hemolysis are promising and should be further explored.

Validation of a qPCR method for determination of viral genome titres of AAV2-based vector preparations.

The viral genome titre is universally used for the dosing of adeno-associated virus (AAV)-based vectors used for gene therapy. To standardise this determination, the development of a common method would be valuable to facilitate comparison of viral doses used in the clinic and in the subsequent quality control of the products. A collaborative study was initiated by the Gene Therapy Working Group of the General European Official Medicines Control Laboratories Network in order to validate a qPCR-based method targeting the ITR2 sequence common to a broad variety of AAV vectors, independently from the serotype of the capsid or from the specific transgene. Five preparations of AAV vectors from various serotypes, including the AAV2/2 (RSS2) and AAV2/8 (RSS8) Reference Standard Stocks (American Type Culture Collection, USA) were used in the study. A plasmid carrying the ITR2 sequence was used to prepare standard curves. Its digestion outside the ITR regions facilitated melting of the hairpin ITR sequence during PCR, allowing better accessibility to the DNA polymerase. The results show that this qPCR method is satisfactory in terms of accuracy and precision. The reproducibility is also acceptable when compared with other similar studies, as it was shown previously that titres obtained by qPCR generally show higher inter-laboratory variability. The use of RSS2 or RSS8 as normalisation control in each assay demonstrated a promising help to identify potential sources of variation in a given laboratory or to smooth out inter-laboratory variations, thus improving reproducibility.

Seroconversion in patients with cancer and oncology health care workers infected by SARS-CoV-2.

BACKGROUND: Patients with cancer have high risk for severe complications and poor outcome to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related disease [coronavirus disease 2019 (COVID-19)]. Almost all subjects with COVID-19 develop anti-SARS-CoV-2 immunoglobulin G (IgG) within 3 weeks after infection. No data are available on the seroconversion rates of cancer patients and COVID-19. PATIENTS AND METHODS: We conducted a multicenter, observational, prospective study that enrolled (i) patients and oncology health professionals with SARS-CoV-2 infection confirmed by real-time RT-PCR assays on nasal/pharyngeal swab specimens; (ii) patients and oncology health professionals with clinical or radiological suspicious of infection by SARS-CoV-2; and (iii) patients with cancer who are considered at high risk for infection and eligible for active therapy and/or major surgery. All enrolled subjects were tested with the 2019-nCoV IgG/IgM Rapid Test Cassette, which is a qualitative membrane-based immunoassay for the detection of IgG and IgM antibodies to SARS-CoV-2. The aim of the study was to evaluate anti-SARS-CoV-2 seroconversion rate in patients with cancer and oncology health care professionals with confirmed or clinically suspected COVID-19. RESULTS: From 30 March 2020 to 11 May 2020, 166 subjects were enrolled in the study. Among them, cancer patients and health workers were 61 (36.7%) and 105 (63.3%), respectively. Overall, 86 subjects (51.8%) had confirmed SARS-CoV-2 diagnosis by RT-PCR testing on nasopharyngeal swab specimen, and 60 (36.2%) had a clinical suspicious of COVID-19. Median time from symptom onset (for cases not confirmed by RT-PCR) or RT-PCR confirmation to serum antibody test was 17 days (interquartile range 26). In the population with confirmed RT-PCR, 83.8% of cases were IgG positive. No difference in IgG positivity was observed between cancer patients and health workers (87.9% versus 80.5%; P = 0.39). CONCLUSIONS: Our data indicate that SARS-CoV-2-specific IgG antibody detection do not differ between cancer patients and healthy subjects.

hERG1 and CA IX expression are associated with disease recurrence in surgically resected clear cell renal carcinoma.

BACKGROUND: In search of novel prognostic biomarkers for clear cell renal carcinoma (ccRCC), we analysed the expression of several proteins related to angiogenesis and hypoxia. METHODS: A monocentric study on 30 consecutive surgical samples from surgically-treated ccRCC patients with a 10-year follow up was performed. The following proteins were analysed by immunohistochemistry: Vascular Endothelial Growth Factor- A (VEGF-A), Platelet-Derived Growth Factor ß Receptor (PDGFRß), VEGF-receptor 1 (Flt1), VEGF-receptor 2 (KDR), Glucose Transporter 1 (GLUT1), Carbonic anhydrase IX (CA-IX) and the hERG1 potassium channel. Data were analysed in conjunction with the clinico-pathological characteristics of the patients and follow up. RESULTS: All the proteins were expressed in the samples, with statistically significant associations of VEGF-A with PDGFRß and Flt1 and hERG1 with CA IX. Notably, hERG1 and CAIX co-immunoprecipitated in primary ccRCC samples and survival analysis showed that the positivity for hERG1 and CA IX had a negative impact on Recurrence Free Survival (RFS) at the univariate analysis. At the multivariate analysis only hERG1 maintained its statistically significant negative impact. CONCLUSIONS: hERG1 expression can be exploited to predict recurrence in surgically-treated ccRCC patients. hERG1 channels form a multiprotein complex with the pH regulator CA IX in primary ccRCC samples their potential use as therapeutic target might be suggested.

Innovative method for recovery and valorization of hydroxytyrosol from olive mill wastewaters.

The nutritional properties of olive oil can be attributed to its oleic acid and phenolic compounds content, acting as natural oxidants to prevent human diseases. In particular, hydroxytyrosol has an anti-inflammatory action similar to omega 3 fatty acids from fish oil. The olive oil production was conducted by two extraction procedures: first, a two-phase extraction giving extra-virgin olive oil and humid pomace, second, a three-phase working process of humid pomace, obtaining another minimum quantity of extra-virgin olive oil, 'dry' pomace devoid of polyphenols, and mill wastewaters rich in anti-oxidant compounds. The aim of this processing was to employ water to extract the highest concentration of polyphenols from humid pomace and convey them in oil mill wastewaters for extraction. Processed olives were 37,200 kg, pomace deprived of polyphenols was equal to 20,400 kg and processing was performed with 500 kg of olives per hour. This method offers advantages of using cheap equipment and technical simplicity.

Recreational Boating in Ligurian Marine Protected Areas (Italy): A Quantitative Evaluation for a Sustainable Management.

Recreational boating is an important economic activity that can also represent a powerful source of interference for biological communities. The monitoring of the recreational boating in all Marine Protected Areas (MPAs) within the Liguria region was conducted in the 2010 summer season and it allowed to obtain information not provided by any official institution. The collaboration of geographically different MPAs in Liguria has led to the implementation of a monitoring framework of recreational boating, and this has made it possible to develop uniform management strategies for all the Ligurian marine parks. This study identifies the optimal number of boats for each MPAs, the number of boats that can anchor in the various parks without creating any impact on the biocenosis of merit, providing a first characterization of recreational boating in Liguria during the high touristic season and providing management recommendation to each MPAs. Generally, the Ligurian MPAs do not present critical situations, the number of boats in each MPA being below the optimal number, with the exception of Portofino MPA, where in the 12.5 % of monitored days more than 220 boats were counted and the mean density for weekend is 1.19 no boats/ha (4 times higher than weekday). The results confirm the dependence of the boats peaking from the holidays and the months of the summer, but also it highlights other factors that can contribute in the choice of the boaters.

Combination of letrozole, metronomic cyclophosphamide and sorafenib is well-tolerated and shows activity in patients with primary breast cancer.

PURPOSE: To assess whether the combination of letrozole, metronomic cyclophosphamide and sorafenib (LCS) is well tolerated and shows activity in primary breast cancer (BC). METHODS: Thirteen oestrogen receptor-positive, postmenopausal, T2-4, N0-1 BC patients received the LCS combination for 6 months. In these patients we examined the pharmacokinetics of sorafenib and cyclophosphamide, toxicity of the regimen, the clinical response to therapy and changes in the levels of biologically relevant biomarkers. RESULTS: Adequate plasma concentrations of sorafenib were achieved in patients when it was dosed in combination with L+C. The mean plasma concentrations of C were consistently lower following administration of LCS, compared with administration of L+C only. The most common drug-related grade 3/4 adverse events were skin rash (69.3%), hand-foot skin reaction (69.3%) and diarrhoea (46.1%). According to RECIST Criteria, a clinical complete response was observed in 6 of 13 patients. A significant reduction in tumour size, evaluated with MRI, was also observed between baseline and 14 days of treatment in all 13 patients (P=0.005). A significant reduction in SUV uptake, measured by (18)FDG-PET/CT, was observed in all patients between baseline and 30 days of treatment (P=0.015) and between baseline and definitive surgery (P=0.0002). Using modified CT Criteria, a response was demonstrated in 8 out of 10 evaluable patients at 30 days and in 11 out of 13 evaluable patients at the definitive surgery. A significant reduction in Ki67 expression was observed in all patients at day 14 compared with baseline (P<0.00001) and in 9 out of 13 patients at the definitive surgery compared with baseline (P<0.03). There was also a significant suppression of CD31 and VEGF-A expression in response to treatment (P=0.01 and P=0.007, respectively). CONCLUSIONS: The LCS combination is feasible and tolerable. The tumour response and target biomarker modulation indicate that the combination is clinically and biologically active.

Role of magnetic resonance in characterising extrahepatic cholangiocarcinomas.

PURPOSE: The purpose of this study was to evaluate the accuracy of magnetic resonance (MR) in correctly locating and characterising biliary strictures in patients affected by extrahepatic cholangiocarcinoma, identify findings suggestive of the disease, identify lesions with similar MR features and possible criteria for differential diagnosis and establish prospective MR accuracy in diagnosis of malignant obstruction of extrahepatic bile ducts. MATERIALS AND METHODS: We retrospectively reviewed the MR examinations of 39 patients affected by extrahepatic cholangiocarcinoma confirmed by histology or cytology. The studies were evaluated for the following parameters: site of obstruction (hilar, proximal or distal), presence of intra- or extrahepatic dilation of bile ducts, morphology of ductal stenosis (gradual tapering or abrupt ending), morphology of the lesion (mass like or circumferential), dimension, signal intensity before contrast medium administration and lesion enhancement after administration of contrast medium. Finally, we assessed the most useful sequence for the diagnosis. In order to evaluate MR accuracy in the diagnosis of malignant obstruction of extrahepatic bile ducts, we prospectively reviewed MR examinations of 74 patients affected by obstructive jaundice (55 malignant lesions and 19 inflammatory lesions). MR diagnosis was compared with histology or cytology considered as the gold standard. RESULTS: MR allowed identification and localisation of 41/41 extrahepatic cholangiocarcinomas. Fifty-four percent of the lesions showed gradual duct tapering; the remaining lesions showed an abrupt ending. Fifty-six percent of the lesions appeared as a circumferential thickening (infiltrative growth); the remaining lesions had a mass-like appearance (expansile growth). Most lesions were hypo- (49%) or isointense (49%) in T1-weighted sequences and hyper- (49%) or isointense (51%) in T2-weighted sequences. Ninety-five percent of the lesions did not enhance significantly in the arterial phase while 98% showed late enhancement (10 min). The most diagnostic sequence (in 76% of cases) was the late-phase gradient-echo (GRE) T1 fat-saturated sequence. MR had good sensitivity (91%) but poor specificity (47%) in characterising stenosis as malignant, given the large number (10/19) of benign lesions evaluated as neoplastic lesions. CONCLUSIONS: MR almost always identified the cause of stenosis and suggested its neoplastic nature if it exhibited a mass-like appearance (extraductal or growing into the choledochus). On the other hand, lesions with parietal thickening, particularly if smaller than 1 cm, require endoscopic cytology or histology because of the high risk of unnecessary procedures for benign lesions.

Dehydrated gelatin drops: a good method for fungi maintenance and preservation.

Some techniques have been proposed to maintain fungi culture collection. However, any choice must ensure the cultural stability and its phenotypic characteristics. This work proposes an adaptation of a preservation method considered by few literature reports: the dehydrated gelatin drops method (DGD). A total of 27 strains of fungi of clinical interest, including four dermatophyte fungi isolates, six filamentous non-dermatophyte fungi, five environment isolated filamentous fungi, six dimorphic fungi and six yeasts were maintained by this method for a seven year period at room temperature. After that time, the macro and micro characteristics of each fungus were studied, allowing the evaluation of the DGD method. In our experience, none of the strains maintained by DGD were found to be contaminated by bacteria or other fungi and no apparent changes were observed in morphology or macroscopic features.

Intramuscular depot medroxyprogesterone versus oral megestrol for the control of postmenopausal hot flashes in breast cancer patients: a randomized study.

BACKGROUND: Hot flashes are frequent in postmenopausal breast cancer patients, especially when treated with tamoxifen. Estrogen replacement therapy is the most effective treatment for hot flashes, but its use is controversial in breast cancer survivors. Progestins may offer a good alternative for the control of hot flashes in this setting; in particular, oral megestrol acetate has been proven effective in a randomized, placebo-controlled clinical trial. With the aim of further improving these results, we have designed a randomized study comparing oral megestrol acetate with depot intramuscular (i.m.) medroxyprogesterone acetate (MPA) for the control of hot flashes in postmenopausal patients with a history of breast cancer. PATIENTS AND METHODS: Seventy-one postmenopausal patients were randomized to receive an i.m. injection of depot MPA 500 mg on days 1, 14 and 28, or oral megestrol acetate 40 mg daily for 6 weeks. Patients recorded daily the number and severity of their hot flashes; response was defined as a > or =50% decrease in the number and severity of hot flashes. RESULTS: At week 6, hot flashes were reduced by 86% on average in the whole group of patients, without significant differences between the two progestins. Response was obtained by 75 and 67% of patients receiving MPA or megestrol, respectively (P = 0.5). Responders were followed to assess maintenance of response (without further treatment), which was significantly better with i.m. MPA: in this group, 89% of responders still showed a benefit at week 24, compared with 45% in the megestrol group (P = 0.03). CONCLUSIONS: Our study shows that a short cycle of i.m. depot MPA injections provides significant and long-lasting relief from postmenopausal hot flashes in patients with a history of breast cancer, offering an alternative to estrogen replacement therapy or prolonged administration of oral megestrol.

Transcription factor PU.1 is necessary for development of thymic and myeloid progenitor-derived dendritic cells.

Dendritic cells (DCs) are a heterogeneous population of cells that are specialized for Ag processing and presentation. These cells are believed to derive from both myeloid- and lymphoid-committed precursors. Normal human PBMC-derived, human CD14+ cell (monocyte)-derived, and mouse hematopoietic progenitor-derived DCs were shown to express the hematopoietic cell-restricted, ets family transcription factor PU.1. These populations represent myeloid progenitor-derived DCs. Hematopoietic progenitor cells from PU.1 gene-disrupted (null) mice were unable to generate MHC class IIhigh, CD11c+ myeloid-derived DCs in vitro. Mouse thymic DCs are proposed to be derived from a committed lymphoid progenitor cell that can give rise to T cells as well as DCs. Previously, we showed that CD4 and CD8 T cells developed in PU.1 null mice in a delayed manner and in reduced number. We examined the thymus of 10- to 12-day-old PU.1 null mice and found no evidence of DEC-205+, MIDC-8+ DCs in this tissue. Our findings indicate that PU.1 regulates the development of both thymic and myeloid progenitor-derived populations of DCs, and expand its known role in hematopoietic development.

The maltose-binding protein as a scaffold for monovalent display of peptides derived from phage libraries.

Random peptide libraries are displayed on filamentous bacteriophage as fusions to either the minor coat protein, pIII, or the major coat protein, pVIII. We have devised a means of isolating the peptide displayed on a phage clone by transferring it to the N-terminus of the maltose-binding protein (MBP) of Escherichia coli encoded by malE. Transfer of a peptide sequence to monomeric MBP eliminates phage-encoded amino acids downstream of the insert peptide as well as avidity effects caused by multivalent display on phage. Peptide:MBP fusions are also easily affinity purified on amylose columns. The pMal-p2 vector was engineered to accept phage DNA encoding pIII- and pVIII-displayed peptides fused to their respective leader sequences. Both types of leader sequence were shown to target the peptide:MBP fusions to the periplasm of E. coli. A streamlined procedure for transferring peptides to MBP was applied to clones that had been isolated from a panel of pVIII-displayed peptide libraries by screening with an HIV-1-specific monoclonal antibody (Ab). By enzyme-linked immunosorbent assay, the Ab bound each of the peptide:MBP fusions and required the presence of a disulfide bridge within each peptide. Some of the peptide:MBP fusions were also analyzed using surface plasmon resonance. Thus, our study shows the value of malE fusion vectors in characterizing phage-displayed peptides.

Probing the tertiary structure of proteins by limited proteolysis and mass spectrometry: the case of Minibody.

A strategy that combines limited proteolysis experiments and mass spectrometric analysis of the fragments generated has been developed to probe protease-accessible sites on the protein surface. This integrated approach has been employed to investigate the tertiary structure of the Minibody, a de novo designed 64-residue protein consisting of a beta-sheet scaffold based on the heavy-chain variable-domain structure of a mouse immunoglobulin and containing two segments corresponding to the hypervariable H1 and H2 regions. The low solubility of the protein prevented a detailed characterization by NMR and/or X-ray. Different proteases were used under strictly controlled conditions and the cleavage sites were mapped onto the anticipated Minibody model, leading to the identification of the most exposed regions. A single-residue mutant was constructed and characterized, following the same procedure, showing a slightly higher correspondence with the predicted model. This strategy can be used to effectively supplement NMR and X-ray investigations of protein tertiary structure, where these procedures cannot provide definitive data, or to verify and refine protein models.

A case of idiopathic myelofibrosis with alloimmunization to HLA-identical platelet transfusions not responsive to antibody absorption over protein-A columns.

A case of idiopathic myelofibrosis has been treated with HLA-identical platelet apheresis concentrates. After a short period the patient also developed refractoriness to the haploidentical siblings. Protein A columns were used to absorb the platelet antibodies with no result. Now two apheresis platelet concentrates are used every month, crossmatched negative products produce good results maintaining cell counts between 20 and 30 x 10(9)/L. The immune mechanism involved is difficult to understand.

The affinity-selection of a minibody polypeptide inhibitor of human interleukin-6.

A major challenge in basic and applied biological research is the engineering of small proteins with pre-determined structures and novel functions. In a limited number of cases, this has been achieved by de novo design. An alternative combinatorial approach is based on the construction of large libraries of random peptides and on methods for the selection of the desired molecules. Here we describe a successful combination of both the rational design and the combinatorial approaches for developing proteins with useful biological functions, in this case the construction of a specific inhibitor of the cytokine human interleukin-6. In previous work, the 'minibody', a 61 residue polypeptide consisting of a beta-pleated framework and two hypervariable regions, was designed, synthesized and expressed on f1 phage surface. We report the construction of a repertoire of 50 million minibodies displayed on phage in which the hypervariable regions have been randomized. One polypeptide which binds tightly and specifically to human interleukin-6 was isolated from this collection of minibody mutants. This particular minibody is an effective inhibitor of the cytokine's biological activity. The approach described here could in principle be applied to other molecular targets.

The making of the minibody: an engineered beta-protein for the display of conformationally constrained peptides.

Conformationally constraining selectable peptides onto a suitable scaffold that enables their conformation to be predicted or readily determined by experimental techniques would considerably boost the drug discovery process by reducing the gap between the discovery of a peptide lead and the design of a peptidomimetic with a more desirable pharmacological profile. With this in mind, we designed the minibody, a 61-residue beta-protein aimed at retaining some desirable features of immunoglobulin variable domains, such as tolerance to sequence variability in selected regions of the protein and predictability of the main chain conformation of the same regions, based on the 'canonical structures' model. To test the ability of the minibody scaffold to support functional sites we also designed a metal binding version of the protein by suitably choosing the sequences of its loops. The minibody was produced both by chemical synthesis and expression in E. coli and characterized by size exclusion chromatography, UV CD (circular dichroism) spectroscopy and metal binding activity. All our data supported the model, but a more detailed structural characterization of the molecule was impaired by its low solubility. We were able to overcome this problem both by further mutagenesis of the framework and by addition of a solubilizing motif. The minibody is being used to select constrained human IL-6 peptidic ligands from a library displayed on the surface of the f1 bacteriophage.

High level expression and rational mutagenesis of a designed protein, the minibody. From an insoluble to a soluble molecule.

We recently described the design and chemical synthesis of the minibody, a 61-residue metal binding beta-protein with a novel fold. Characterization of the polypeptide by circular dichroism spectroscopy, size exclusion chromatography, and metal binding studies showed the molecule to be folded, monomeric, globular and able to bind metals. The main obstacle which prevented a more detailed characterization was the very low solubility of the protein in water (about 10 microM). To address this problem, we used two independent approaches: (1) mutagenesis of the beta-sheet framework residues and (2) addition of a solubilizing motif, made of three lysine residues, at the N or C termini. Engineering and production of mutants was facilitated by the achievement of high level expression of the protein in Escherichia coli. Both approaches led to minibody variants with a solubility ranging from tenfold higher up to millimolar levels. For the best-characterized variant obtained so far, the thermodynamic stability calculated from denaturant-induced transition is identical to that of the parent, poorly soluble, molecule.

A designed metal-binding protein with a novel fold.

A major challenge in protein design is to create stable scaffolds into which tailored functions can be introduced. Here we present the design, synthesis and characterization of a 61-residue all-beta protein: the minibody. We used a portion of the heavy chain variable domain of an immunoglobulin as a template, obtaining a molecule with a novel beta-sheet scaffold and two regions corresponding to the hypervariable loops H1 and H2. To exploit the potential for creating functional centres in the minibody, we engineered a metal-binding site into it. This site is formed by one histidine in H1 and two in H2. The protein is folded, compact and able to bind metal, thus representing the first designed beta-protein with a novel fold and a tailored function. By randomizing the sequence of the hypervariable loops, we are using the minibody scaffold to construct a conformationally constrained peptide library displayed on phage.