COVID-19 AND THE THYROID FUNCTION IN PATIENTS WITH HCV- ASSOCIATED HEPATOCELLULAR CARCINOMA.

Context: COVID-19 is more than a respiratory infection, with deep implications regarding multiple systems and organs. Thyroid damage is frequent in COVID-19 and may overlap previous HCV or HCC associated diseases. Objective: The objective of this study is to determine the effects of COVID-19 in patients with HCV associated HCC and thyroid comorbidities. Design: We performed a retrospective study of the thyroid function tests and autoantibodies in patients with HCV-associated HCC prior and during COVID-19. Subjects and Methods: We included 52 consecutive patients with HCV-associated HCC and documented thyroid disease, diagnosed with COVID -19 between April and October 2020. Serum values of thyroid-stimulating hormone, free T3, free T4, anti-thyroglobulin antibodies and anti-thyroid peroxydase antibodies were determined and compared to baseline levels. Results: At baseline, 44 patients had positive antithyroid antibodies, 6 had hypothyroidism in substitution and 2 had hyperthyroidism under treatment. During COVID-19 we found an increase in serum values of antithyroid antibodies, and decreased levels of TSH, freeT3 and freeT4 levels. Specific therapies were discontinued in one patient with hyperthyroidism and 3 patients with hypothyroidism. Conclusion: There is a significant impact of COVID-19 on the thyroid homeostasis; a long-term prognostic value for patients with HCC infected with COVID-19 required further extensive research.

Tick species from Africa by migratory birds: a 3-year study in Italy.

The role of resident or migratory birds in dispersal of tick species and tick-borne pathogens is still poorly known in Italy. We report here the results of a 3-year project based on sampling ticks from migratory birds, as well as from the vegetation at three stop-over sites for migrants, namely the islands of Ventotene (Latium), Asinara (Sardinia) and Ustica (Sicily). During the spring seasons from 2017-2019, in total 2681 ticks were collected, 2344 of which were sampled from migratory birds and 337 from the vegetation. Ticks were identified by morphology or by molecular tools when necessary. In total, 16 tick species were identified among which the following were exclusively found on birds: Hyalomma rufipes (43.3%), Hy. truncatum (0.1%), Ixodes frontalis (11.8%), Ix. inopinatus (0.2%), Ix. ricinus (3%), Haemaphysalis punctata (0.08%), Hae. erinacei (0.1%), Amblyomma variegatum (0.08%) and Argas vulgaris 0.1%), whereas five species were exclusively collected from the vegetation: Rhipicephalus bursa (10.5%), Rh. turanicus (5.9%), Rh. sanguineus sensu lato (2%), Rh. pusillus (2.4%), Hae. sulcata (0.08%). Hy. marginatum (10.3%) and Ix. ventalloi (9.3%) were found both on birds and on the vegetation on the island Ustica. It is worth noting that the search for ticks on the vegetation did not detect allochthonous tick species. Although we found several interesting local species and allochthonous ticks like Hy. rufipes, Am. variegatum and Ar. vulgaris on birds, further investigations are needed to better define the possible role of migratory birds in the introduction of ticks and tick-borne diseases in Italy, above all after the evidence of imported ticks positive to Crimean Congo hemorrhagic fever (CCHF) virus in several European countries.

The impact of COVID 19 infection on HCV-induced thyroid disease.

Context: As we progress into the COVID-19 pandemic, it has become apparent that this infection is associated with a multitude of systemic effects, some involving the thyroid gland. The thyroid is also frequently affected in the HCV chronic infection. Objective: The objective of this study is to determine the effects of COVID-19 infection on the presence and severity of thyroid disorders associated with chronic HCV infection, at short and mid-term follow-up. Design: We prospectively evaluated patients with documented HCV- associated thyroid disease (with sustained virologic response after antiviral therapy). Subjects and Methods: The study group consisted of 42 patients with HCV- associated thyroid disease, diagnosed with COVID -19 infection between April and October 2020. We determined serum values of thyroid-stimulating hormone, freeT3, free T4, anti-thyroglobulin antibodies and anti-thyroid peroxidase antibodies at one and three months after resolution of infection and compared them to the baseline characteristics of the patient. We also evaluated the changes in thyroid substitution treatments or antithyroid drugs. Results: At baseline, out of the 42 patients, 5 presented hypothyroidism under levothyroxine substitution therapy, while 2 presented hyperthyroidism under methimazole therapy; 37 patients had positive antithyroid antibodies. At one month follow-up, we note an increase in serum values of antibodies, with a decrease in TSH, freeT3 and freeT4 levels, correlated with the severity of COVID-19 infection. Two patients required discontinuation of levothyroxine. At 3 months follow-up, lower levels of antithyroid antibodies were recorded, with an increase in TSH levels. No medication doses were adjusted at this time. Conclusion: Among the systemic effects of COVID-19, the impact of thyroid dysfunction should not be underestimated, especially in the presence of pre-existing conditions, such as HCV infection.

Nanoparticle delivery of grape seed-derived proanthocyanidins to airway epithelial cells dampens oxidative stress and inflammation.

BACKGROUND: Chronic respiratory diseases, whose one of the hallmarks is oxidative stress, are still incurable and need novel therapeutic tools and pharmaceutical agents. The phenolic compounds contained in grape are endowed with well-recognized anti-oxidant, anti-inflammatory, anti-cancer, and anti-aging activities. Considering that natural anti-oxidants, such as proanthocyanidins, have poor water solubility and oral bioavailability, we have developed a drug delivery system based on solid lipid nanoparticles (SLN), apt to encapsulate grape seed extract (GSE), containing proanthocyanidins. METHODS: Plain, 6-coumarin (6-Coum), DiR- and GSE-loaded SLN were produced with the melt-emulsion method. Physicochemical characterization of all prepared SLN was determined by photon correlation spectroscopy and laser Doppler anemometry. MTT assay (spectrophotometry) and propidium iodide (PI) assay (cytofluorimetry) were used to assess cell viability. Flow cytometry coupled with cell imaging was performed for assessing apoptosis and necrosis by Annexin V/7-AAD staining (plain SLE), cell internalization (6-Coum-SLN) and reactive oxygen species (ROS) production (SLN-GSE). NF-κB nuclear translocation was studied by immunofluorescence. In vivo bio-imaging was used to assess lung deposition and persistence of aerosolized DiR-loaded SLN. RESULTS: Plain SLN were not cytotoxic when incubated with H441 airway epithelial cells, as judged by both PI and MTT assays as well as by apoptosis/necrosis evaluation. 6-Coum-loaded SLN were taken up by H441 cells in a dose-dependent fashion and persisted into cells at detectable levels up to 16 days. SLN were detected in mice lungs up to 6 days. SLN-GSE possessed 243 nm as mean diameter, were negatively charged, and stable in size at 37 °C in Simulated Lung Fluid up to 48 h and at 4 °C in double distilled water up to 2 months. The content of SLN in proanthocyanidins remained unvaried up to 2 months. GSE-loaded SLN determined a significant reduction in ROS production when added 24-72 h before the stimulation with hydrogen peroxide. Interestingly, while at 24 h free GSE determined a higher decrease of ROS production than SLN-GSE, the contrary was seen at 48 and 72 h. Similar results were observed for NF-κB nuclear translocation. CONCLUSIONS: SLN are a biocompatible drug delivery system for natural anti-oxidants obtained from grape seed in a model of oxidative stress in airway epithelial cells. They feature stability and long-term persistence inside cells where they release proanthocyanidins. These results could pave the way to novel anti-oxidant and anti-inflammatory therapies for chronic respiratory diseases.

A SEVERE CASE OF HYPERGLYCEMIA IN A KIDNEY TRANSPLANT RECIPIENT UNDERGOING INTERFERON-FREE THERAPY FOR CHRONIC HEPATITIS C.

CONTEXT: Hepatitis C and diabetes represent important health problems globally. The new-onset diabetes after transplantation is a particular entity that appears due to the use of immunosuppression among transplanted patients. OBJECTIVE: We aim to describe the clinical and biological aspects of severe hyperglycemia in a kidney transplant recipient undergoing Interferon-free therapy for chronic hepatitis C, discussing the interference of different factors with the glucose metabolism. DESIGN: The occurrence of diabetes in a patient with history of renal transplantation and Interferon-free treated hepatitis C was studied from both clinical and paraclinical points of view. SUBJECTS AND METHODS: When presenting to the hospital, extensive blood tests were performed on the patient, revealing significant hyperglycemia and an elevated level of blood tacrolimus. Creatinine clearance was calculated. ECG presented T-wave alterations. Intensive insulin protocol was applied, the case being managed in a multidisciplinary approach. RESULTS: Blood glucose and tacrolimus were slowly normalized, under therapy. The antiviral treatment was continued, with the achievement of sustained virologic response. CONCLUSIONS: Diabetes mellitus can have many causes, hepatitis C and transplantation both having an impact on glucose metabolism. The association of the three entities should be carefully managed, due to its enhancing effect on morbidity and mortality.

Computational Mechanistic Study of Thionation of Carbonyl Compounds with Lawesson's Reagent.

The thionation reaction of carbonyl compounds with Lawesson's reagent (LR) has been studied using density functional theory methods and topological analyses. After dissociation of LR, the reaction takes place through a two-step mechanism involving (i) a concerted cycloaddition between one monomer and the carbonyl compound to form a four-membered intermediate and (ii) a cycloreversion leading to the thiocarbonyl derivative and phenyl(thioxo)phosphine oxide. Topological analyses confirmed the concertedness and asynchronicity of the process. The second step is the rate-limiting one, and the whole process resembles the currently accepted mechanism for the lithium salt-free Wittig reaction. No zwitterionic intermediates are formed during the reaction, although stabilizing electrostatic interactions are present in initial stages. Phenyl(thioxo)phosphine oxide formed in the thionation reaction is capable of performing a second thionation, although with energy barriers higher than the first one. The driving force of the thionation reactions is the formation of trimers from the resulting monomers. In agreement with experimental observations, the amides are the most reactive when compared with esters, aldehydes, and ketones and the reaction is slightly influenced by the polarity of the solvent. Whereas for amides and esters substituents have little effect, aldehydes and ketones are influenced by both steric and electronic effects.

An analysis of cattle farmers' perceptions of drivers and barriers to on-farm control of Escherichia coli O157.

Structural equation modelling and survey data were used to test determinants' influence on farmers' intentions towards Escherichia coli O157 on-farm control. Results suggest that farmers more likely to show willingness to spend money/time or vaccinate to control Escherichia coli O157 are those: who think farmers are most responsible for control; whose income depends more on opening farms to the public; with stronger disease control attitudes; affected by outbreaks; with better knowledge and more informed; with stronger perceptions of biosecurity measures' practicality; using a health plan; who think farmers are the main beneficiaries of control; and whose farms are dairy rather than beef. The findings might suggest that farmers may implement on-farm controls for E. coli O157 if they identify a clear hazard and if there is greater knowledge of the safety and efficacy of the proposed controls.

Evaluation of vector competence for West Nile virus in Italian Stegomyia albopicta (=Aedes albopictus) mosquitoes.

West Nile virus (WNV) is a zoonotic arboviral pathogen transmitted by mosquitoes in a cycle that involves wild birds as reservoir hosts. The virus is responsible for outbreaks of viral encephalitis in humans and horses. In Europe, Culex pipiens (Diptera: Culicidae) is considered to be the main vector of WNV, but other species such as Stegomyia albopicta (=Aedes albopictus) (Diptera: Culicidae) may also act as competent vectors of this virus. Since 2008 human cases of WNV disease have been reported in northeast Italy. In 2011, new areas of southern Italy became involved and a first outbreak of WNV lineage 1 occurred on the island of Sardinia. On the assumption that a potential involvement of St. albopicta in WNV transmission cannot be excluded, and in order to evaluate the competence of this species for the virus, an experimental infection of an St. albopicta laboratory colony, established from mosquitoes collected in Sardinia, was carried out. The results were compared with those obtained in a colony of the main vector Cx. pipiens. The study showed St. albopicta collected on Sardinia to be susceptible to WNV infection, which suggests this Italian mosquito species is able to act as a possible secondary vector, particularly in urban areas where the species reaches high levels of seasonal abundance.

Management of hepatocellular carcinoma -- experience of a single center.

BACKGROUND AND AIMS: Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and the third most common cause of cancer-related death. We aim to study the diagnosis and treatment options for HCC. METHODS: We used standard methods of diagnosis for HCC:radiology, determining serum alpha fetoprotein (AFP). We included 190 patients diagnosed with HCC between April 2011 and May 2012. RESULTS: All patients were classified and treated according to the BCLC staging. Our study included 43 patients with early stage HCC, 58 patients with intermediate stage HCC (Stage B) and 89 patients with advanced stage HCC (Stage C). Most patients in the early stage underwent local ablation, while TACE was preferred in 46 patients in the intermediate stage.Systemic therapy was the most frequent treatment for patients in the advanced stage (48 patients), followed by Sorafenib (16 patients). 21 patients with end-stage disease did not receive treatment. Survival rates depended on the HCC stage: 2 - 18 months in the intermediate stage and 1 - 12 months in the advanced stage. CONCLUSION: Early diagnosis of HCC is essential in improving the patients outcomes, as there are several classic therapeutic options and new emerging ones addressing patients with early stage disease.

A rare case of ileal metastasis from cervical cancer.

We present the case of a 70-year-old woman, with a history of radiation-treated and surgically- resected cervical cancer, who was admitted to our clinic for intermittent sub occlusive symptoms. CT scan revealed a liver nodule and intestinal obstruction. The patient underwent surgery for excision of suspected liver metastasis and resolution of intestinal obstruction.Intraoperatively an ileal tumour was found to be the cause of the obstruction. Anatomo-pathological findings were consistent with an ileal metastasis from the cervical cancer.The liver nodule was only an area of focal steatosis.

Trypanosoma cruzi heparin-binding proteins present a flagellar membrane localization and serine proteinase activity.

Heparin-binding proteins (HBPs) play a key role in Trypanosoma cruzi-host cell interactions. HBPs recognize heparan sulfate (HS) at the host cell surface and are able to induce the cytoadherence and invasion of this parasite. Herein, we analysed the biochemical properties of the HBPs and also evaluated the expression and subcellular localization of HBPs in T. cruzi trypomastigotes. A flow cytometry analysis revealed that HBPs are highly expressed at the surface of trypomastigotes, and their peculiar localization mainly at the flagellar membrane, which is known as an important signalling domain, may enhance their binding to HS and elicit the parasite invasion. The plasmon surface resonance results demonstrated the stability of HBPs and their affinity to HS and heparin. Additionally, gelatinolytic activities of 70 kDa, 65·8 kDa and 59 kDa HBPs over a broad pH range (5·5-8·0) were revealed using a zymography assay. These proteolytic activities were sensitive to serine proteinase inhibitors, such as aprotinin and phenylmethylsulfonyl fluoride, suggesting that HBPs have the properties of trypsin-like proteinases.

Environmental efficiency of alternative dairy systems: a productive efficiency approach.

Agriculture across the globe needs to produce "more with less." Productivity should be increased in a sustainable manner so that the environment is not further degraded, management practices are both socially acceptable and economically favorable, and future generations are not disadvantaged. The objective of this paper was to compare the environmental efficiency of 2 divergent strains of Holstein-Friesian cows across 2 contrasting dairy management systems (grazing and nongrazing) over multiple years and so expose any genetic × environment (G × E) interaction. The models were an extension of the traditional efficiency analysis to account for undesirable outputs (pollutants), and estimate efficiency measures that allow for the asymmetric treatment of desirable outputs (i.e., milk production) and undesirable outputs. Two types of models were estimated, one considering production inputs (land, nitrogen fertilizers, feed, and cows) and the other not, thus allowing the assessment of the effect of inputs by comparing efficiency values and rankings between models. Each model type had 2 versions, one including 2 types of pollutants (greenhouse gas emissions, nitrogen surplus) and the other 3 (greenhouse gas emissions, nitrogen surplus, and phosphorus surplus). Significant differences were found between efficiency scores among the systems. Results indicated no G × E interaction; however, even though the select genetic merit herd consuming a diet with a higher proportion of concentrated feeds was most efficient in the majority of models, cows of the same genetic merit on higher forage diets could be just as efficient. Efficiency scores for the low forage groups were less variable from year to year, which reflected the uniformity of purchased concentrate feeds. The results also indicate that inputs play an important role in the measurement of environmental efficiency of dairy systems and that animal health variables (incidence of udder health disorders and body condition score) have a significant effect on the environmental efficiency of each dairy system. We conclude that traditional narrow measures of performance may not always distinguish dairy farming systems best fitted to future requirements.

Argas ticks (Ixodida: Argasidae) on migratory birds from Africa: first record of a genotype close to Argas africolumbae in Italy.

In spring, migratory birds reach Europe, mainly from sub-Saharan Africa or from northern African countries. Avian species may be implicated in the spread of pathogens, either as reservoirs, hosts or carriers of infected ectoparasites. In 2021, on Ventotene Island (Latium region, Italy) within a project focused on the potential incoming pathogens via migratory birds from Africa, we found two larvae of Argas sp., on the redstart Phoenicurus phoenicurus, that shared morphological features with the African Argas (Argas) africolumbae. Comparison of the tested larval DNA sequences to the adult reference sequences showed the highest identity (> 92%) with homologous sequences of A. africolumbae collected in South Africa and in Spain. This study reports the first detection of Argas africolumbae-like specimens in Italy.

Trypanosoma cruzi heparin-binding proteins mediate the adherence of epimastigotes to the midgut epithelial cells of Rhodnius prolixus.

Heparin-binding proteins (HBPs) have been demonstrated in both infective forms of Trypanosoma cruzi and are involved in the recognition and invasion of mammalian cells. In this study, we evaluated the potential biological function of these proteins during the parasite-vector interaction. HBPs, with molecular masses of 65·8 kDa and 59 kDa, were isolated from epimastigotes by heparin affinity chromatography and identified by biotin-conjugated sulfated glycosaminoglycans (GAGs). Surface plasmon resonance biosensor analysis demonstrated stable receptor-ligand binding based on the association and dissociation values. Pre-incubation of epimastigotes with GAGs led to an inhibition of parasite binding to immobilized heparin. Competition assays were performed to evaluate the role of the HBP-GAG interaction in the recognition and adhesion of epimastigotes to midgut epithelial cells of Rhodnius prolixus. Epithelial cells pre-incubated with HBPs yielded a 3·8-fold inhibition in the adhesion of epimastigotes. The pre-treatment of epimastigotes with heparin, heparan sulfate and chondroitin sulfate significantly inhibited parasite adhesion to midgut epithelial cells, which was confirmed by scanning electron microscopy. We provide evidence that heparin-binding proteins are found on the surface of T. cruzi epimastigotes and demonstrate their key role in the recognition of sulfated GAGs on the surface of midgut epithelial cells of the insect vector.

Impact of environmental changes and human-related factors on the potential malaria vector, Anopheles labranchiae (Diptera: Culicidae), in Maremma, Central Italy.

The Maremma Plain (central Italy) was hyper-endemic for malaria until the mid-20th century, when a national campaign for malaria elimination drastically reduced the presence of the main vector Anopheles labranchiae Falleroni. However, the introduction of rice cultivation over 30 yr ago has led to an increase in the An. labranchiae population and concern over possible malaria reemergence. We studied the impact of anthropogenic environmental changes on the abundance and distribution of An. labranchiae in Maremma, focusing on rice fields, the main breeding sites. Adults and larvae were collected in three main areas with diverse ecological characteristics. Data were collected on human activity, land use, and seasonal climatic and demographic variations. We also interviewed residents and tourists regarding their knowledge of malaria. Our findings showed that the most important environmental changes have occurred along the coast; An. labranchiae foci are present throughout the area, with massive reproduction strictly related to rice cultivation in coastal areas. Although the abundance of this species has drastically decreased over the past 30 yr, it remains high and, together with climatic conditions and the potential introduction of gametocyte carriers, it may represent a threat for the occurrence of autochthonous malaria cases. Our findings suggest the need for the continuous monitoring of An. labranchiae in the study area. In addition to entomological surveillance, more detailed knowledge of human-induced environmental changes is needed, so as to have a more complete database that can be used for vector-control plans and for properly managing emergencies related to autochthonous introduced cases.

High prevalence of latent tuberculosis infection in autoimmune disorders such as psoriasis and in chronic respiratory diseases, including lung cancer.

The early diagnosis and treatment of individuals harboring M. tuberculosis is key to ensuring the effectiveness of health programs aimed at the elimination of tuberculosis (TB). Monitoring for TB also has other important health care implications for the related immune pathology caused by the chronic inflammatory response to M. tuberculosis. Moreover, the recent introduction of biologic therapies for the treatment of several immune-mediated inflammatory diseases has shown unexpected high frequencies of reactivation of latent TB. The present cross-sectional study is aimed at estimating the prevalence of latent tuberculosis infection (LTBI) in different groups of subjects, either undergoing a routine program of screening for TB or a clinical monitoring of autoimmune or lung disorders, by analyzing their immune response in vitro to a pool of different M. tuberculosis antigens through an IFN-gamma-release assay (IGRA). We consecutively tested 1,644 subjects including health care workers (931), healthy immigrants from different countries (93), patients with a diagnosis of psoriasis (405), patients with lung inflammatory disease (60) or lung neoplasia (32) and a group of HIV-1 infected Italian subjects (120). The prevalence of IGRAs positive responses among health care workers was 8.9 percent. In comparison, significantly higher frequencies were found in healthy immigrant subjects (33.3%), similar to those found in inflammatory broncho-pneumopathies (34.5%) or lung cancer (29.6%). Interestingly, an unexpected high prevalence was also found in patients affected by psoriasis (18.0%), while HIV-infected subjects had values comparable to those of health care workers (10.8%). An age cut-off was determined and applied for each group by receiver operating characteristic (ROC) curves in order to perform the statistical analysis among age-comparable groups. Multivariate analysis showed that the age and clinical conditions such as having a diagnosis of psoriasis or a lung inflammatory disease were independent risk factors for developing an IGRA positive response. This study highlights an unprecedented high prevalence of IGRA positive responses among patients affected by psoriasis and emphasizes the need for a preliminary assessment of LTBI before the administration of any biologic therapy based on cytokine antagonists such as anti-TNF-alpha. Moreover, screening for LTBI should be routinely performed in the presence of a chronic pulmonary disease.

Involvement of host cell heparan sulfate proteoglycan in Trypanosoma cruzi amastigote attachment and invasion.

Cell surface glycosaminoglycans (GAGs) play an important role in the attachment and invasion process of a variety of intracellular pathogens. We have previously demonstrated that heparan sulfate proteoglycans (HSPG) mediate the invasion of trypomastigote forms of Trypanosoma cruzi in cardiomyocytes. Herein, we analysed whether GAGs are also implicated in amastigote invasion. Competition assays with soluble GAGs revealed that treatment of T. cruzi amastigotes with heparin and heparan sulfate leads to a reduction in the infection ratio, achieving 82% and 65% inhibition of invasion, respectively. Other sulfated GAGs, such as chondroitin sulfate, dermatan sulfate and keratan sulfate, had no effect on the invasion process. In addition, a significant decrease in infection occurred after interaction of amastigotes with GAG-deficient Chinese Hamster Ovary (CHO) cells, decreasing from 20% and 28% in wild-type CHO cells to 5% and 9% in the mutant cells after 2 h and 4 h of infection, respectively. These findings suggest that amastigote invasion also involves host cell surface heparan sulfate proteoglycans. The knowledge of the mechanism triggered by heparan sulfate-binding T. cruzi proteins may provide new potential candidates for Chagas disease therapy.

Midline mandibular osteotomy in an asymmetric patient.

This case report shows the possibility of the application of a mandibular osteotomy to resolve mandibular asymmetry with independent and discordant movements of both bony segments. The authors report the case of a 25-year-old woman referred for mandibular asymmetry, with a transverse excess of the right hemi mandible and vertical defect of the left one. The patient underwent a bilateral sagittal split osteotomy, midline osteotomy, and genioplasty, which corrected the mandibular asymmetry with contraction of the entire right hemi mandible. A slight left vertical increase was also obtained through the surgically created lateral open bite. In the follow-up assessment, the patient's face appeared symmetrical with normalization of the bizygomatic-bigonial relationships, and the facial shape corresponded to ideal anthropometric features. This technique resulted in resolution of mandibular asymmetry. In addition, mandibular osteotomy permits the esthetic management of the shape of the entire mandibular body in relation to the other third of the face.

Aedes albopictus in Rome: results and perspectives after 10 years of monitoring.

In 1997, Aedes albopictus (Skuse 1894) was detected in Rome in two opposite areas of the city. In the following 2 years, the species quickly spread. In 2000, scattered foci of the species were reported in the whole urban area and in the outskirts of the capital city. In Rome, Ae. albopictus seems to have found optimal environmental conditions to proliferate and to overwinter through and without diapausing eggs. In ten years Ae. albopictus has colonized the whole urban area through three phases: first massive spread, following maintenance of infestation, and colonization of alternative winter breeding sites with favorable climatic conditions. Data collected during the 2007 show that rainfall is no longer the most important factor for the development of the species, with respect to the past. In fact Ae. albopictus probably has found new alternative larval breeding sites through the colonization of small water collections refilled periodically by human activities. During 2007-2008 winter season, in order to evaluate the species adaptability, a study of eggs hatching and length of larval cycle at low temperatures, was carried out in laboratory and in simulated field conditions. Data and results are showed and discussed also by the light of existing literature.

The influence of pseudohalide ligands on the SIM behaviour of four-coordinate benzylimidazole-containing cobalt(ii) complexes.

Three, mononuclear complexes of the formula [Co(bmim)2(SCN)2] (1), [Co(bmim)2(NCO)2] (2) and [Co(bmim)2(N3)2] (3) [bmim = 1-benzyl-2-methylimidazole] were prepared and structurally analyzed by single-crystal X-ray crystallography. The cobalt(ii) ions in 1-3 are tetrahedrally coordinated with two bmim molecules and two pseudohalide anions. The angular distortion parameter δ was calculated and the SHAPE program (based on the CShM concept) was used for 1-3 to estimate the angular distortion from an ideal tetrahedron. The molecules of 1-3 are effectively separated, and the values of the shortest distance of cobalt-cobalt are 8.442(6) and 6.774(8) Å for 1, 10.349(8) and 10.716(8) Å for 2 and 6.778(1) and 9.232(1) Å for 3. Direct current (dc) magnetic susceptibility measurements on the crushed crystals of 1-3 were carried out in the temperature range 1.9-295 K. The variable-temperature magnetic data of 1-3 mainly obey the zero-field splitting effect (D) of the 4A2 ground term of the tetrahedral cobalt(ii) complexes (2D being the energy gap between the |±1/2 and |±3/2 levels of the spin). The analysis of their magnetic data through the Hamiltonian H = D[S2z - S(S + 1)/3] + E(Sx2 - Sy2) + gßHS led to the following best-fit parameters: g = 2.29, D = -7.5 cm-1 and E/D = 0.106 (1), g = 2.28, D = + 6.3 cm-1 and E/D = 0.007 (2) and g = 2.36, D = + 6.7 cm-1 and E/D = 0.090 (3). The signs of D for 1-3 were confirmed by Q-band EPR spectra on powdered samples in the temperature range 4.0-20 K. Field-induced SIM behaviour was observed for 1-3 below 4.0 K, and the frequency-dependent maxima of χ''M were observed for 1 and only incipient signals of χ''M occurred for 2 and 3. The values of the exponential factor (τ0) and activation energy (Ea) for 1-3 which were obtained from the Arrhenius plot suggest a single relaxation process characteristic of an Orbach mechanism.