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Typhoid fever is a major cause of morbidity and mortality in developing countries. Vaccines based on the Vi capsular polysaccharide are licensed or in development against typhoid fever. Vi content is a critical quality attribute for vaccines release, to monitor their stability and to ensure appropriate immune response. Vi polysaccharide is a homopolymer of α-1,4- N -acetylgalactosaminouronic acid, O-acetylated at the C-3 position, resistant to the commonly used acid hydrolysis for sugar chain depolymerization before monomer quantification. We previously developed a quantification method based on strong alkaline hydrolysis followed by High Performance Anion Exchange Chromatography-Pulsed Amperometric Detection analysis, but with low sensitivity and use for quantification of an unknown product coming from polysaccharide depolymerization. Here we describe the development of a method for Vi polysaccharide quantification based on acid hydrolysis with concomitant use of trifluoroacetic and hydrochloric acids. A Design of Experiment approach was used for the identification of the optimal hydrolysis conditions. The method is 100-fold more sensitive than the previous one, and specifically, resulting in the formation of a known product, confirmed to be the Vi monomer both de-O- and de-N-acetylated by mono- and bidimensional Nuclear Magnetic Resonance spectroscopy and mass spectrometry. Accuracy and precision were determined, and chromatographic conditions were improved to result in reduced time of analysis. This method will facilitate characterization of Vi-based vaccines. Furthermore, a similar approach has the potential to be extended to other polysaccharides containing 2-amino uronic acids, as already verified here for Shigella sonnei O-antigen, Streptococcus pneumoniae serotype 12F, and Staphylococcus aureus types 5 and 8 capsular polysaccharides.

This report focuses on epidemiological and clinical features of dengue fever (DF) in Tuscany (Italy) between 2006 and 2012. Sixty-one DF cases were diagnosed, 32 of which were in the period of Aedes albopictus activity. Some clinical (arthralgia/myalgia, nausea/vomiting, and skin rash), laboratory (leukopenia and thrombocytopenia), and epidemiological characteristics (travel in a continent other than Africa) significantly distinguished DF cases from other febrile illnesses. Our data stress the importance of increasing awareness on dengue in Italy among clinicians in order to reach an early diagnosis in returning travelers and to implement appropriate clinical and public health interventions., (© 2014 International Society of Travel Medicine.)

Aim: Two recurrent cases of severe acute liver injury attributed to the use of a wild germander decoction, prepared with some variation in traditional method has been reported. The aim of the present study was to correlate the hepatotoxic effect observed in patients who consumed germander decoction with teucrin A levels. Antioxidant properties were analyzed to assess any possible differences between the decoction used traditionally by the family (without negative consequences) and the decoction taken by the patients., Materials and Methods: Different types of germander decoctions were prepared in the laboratory by simulating the same conditions for preparing the decoction by the patients and their family members. The levels of teucrin A, the polyphenols and the antioxidant power were determined. One-way analysis of variance was used to test for differences between the groups., Results and Conclusions: The extract consumed by the patients had higher concentration of teucrin A, lower antioxidant activity and lower content of polyphenols compared with the traditional decoction, revealing an inverse relationship between teucrin A content and antioxidant capacity. These case reports emphasize that more information is needed on the safety and quality of these natural products.

Highly active antiretroviral therapy dramatically decreases in vivo viral replication to levels below the level of clinical detection, but does not eradicate HIV-1 infection on the basis of persistent low-level or cryptic viral replication and latent provirus in resting CD4+ T lymphocytes. Immune activation therapy has begun to be used in attempts to increase the turnover rate of the latent virus reservoir through activation of infected cells that comprise this reservoir, in order to promote cell death and accelerate virus clearance. Recent reports have not demonstrated complete virus ablation. Autologous hematopoietic cell transplantation now appears as a safe, feasible, and reasonable approach for Aids-related lymphoma in patients who meet criteria for transplantation. The hypothesis is based on the possibility that hematopoietic stem cells from a HIV-positive patient could be collected before the patient becomes infected with HIV. Then, the proposed treatment consists of the following assumptions. HAART keeps viral replication below the level of detection, limiting the infection to latent provirus in resting CD4+ T lymphocytes. It is presumed here that myeloablative conditioning regimen can lead to the killing of all the cells that, in theory, harbour the virus. The following transplantation of the autologous hematopoietic stem cells, collected before HIV infection, would allow the complete recovery. The hypothesis is to be tested on a suitable animal model. After the collection of hematopoietic stem cells, the animal is experimentally infected with the immunodeficiency virus. HAART is given after plasma viral RNA becomes detectable. By myeloablative conditioning regimen all the cells harbouring the virus are supposed to be killed. Then, as the viral load is kept undetectable by HAART, the animal undergoes autologous hematopoietic stem cell transplantation. Antiretroviral therapy is interrupted a month after engraftment has taken place. Although hematopoietic stem cells from man before infection with HIV are unlikely to be available, a successful test on the animal would suggest a new approach which could allow the cure of HIV in future.

The Infectious Diseases Unit of Lucca Hospital conducted a multicentric retrospective study to evaluate the epidemiological and clinical features of adult patients affected by bacterial meningitis attending all the Infectious Diseases Units of Tuscany (Italy) from July 1999 to June 2004. A specific questionnaire was sent to all the units to collect information about each case of bacterial meningitis occurring in patients older than sixteen. Patients with meningitis by Mycobacterium tuberculosis were excluded from the analysis. Nine out of 12 Infectious Diseases Units of Tuscany took part in the study and 197 cases were identified. Most cases of meningitis occurred during 2002 with a slight reduction in cases in subsequent years. Streptococcus pneumoniae and Neisseria meningitidis were the most frequently isolated pathogens with an increase in diagnosis from 1999 to 2004; in 23.8% of patients no pathogens were isolated, with a reduction in meningitis from unknown aetiology from 1999 to 2004. Most patients were treated with a combination of two antibiotics, and corticosteroid drugs were added to the therapy; in the group of patients treated with corticosteroid drugs invalidating complications occurred in 23% of cases and 5% of patients died. In all, 27 out of 197 subjects (13.7%) developed invalidating complications and 20 out of 197 patients (10.2%) died.

We report here the results of a retrospective study carried out on 200 tuberculosis cases admitted to the Hospital of Siena during the period 1994-2003. For each case, epidemiological, clinical and microbiological data were collected in order to analyze the trend of tuberculosis over the years and to compare our experience with similar studies. Indigenous patients were significantly older than immigrants (60.1 vs 34.2 yrs) more frequently affected by underlying chronic diseases. Overcrowding and HIV infection were predisposing conditions in 30 subjects (15% of cases) recently arrived from high endemicity countries. Pulmonary tuberculosis (TB) was diagnosed in 71% of cases, irrespective of origin. The death rate was 5%. Microbiological investigation was positive in 74.4% of examined subjects; 9.8% of isolates were resistant to one or more antituberculous drugs. The number of cases admitted to the Hospital seems to have slowly decreased in the last few years; factors that may influence this trend are discussed. Our results confirm a distinct epidemiological pattern of the disease between indigenous patients and immigrants, which is typical of low-endemicity countries. The delay in the diagnosis and management of the disease observed in this case-series report underlines the need to improve information on TB and skill in treatment, and to maintain specialized centres.