The experience of virtual reality: are individual differences in mental imagery associated with sense of presence?

The concept of "presence" describes the quality of subjective experience in immersive virtual reality (IVR). Presence refers to a specific state of consciousness: we behave and feel as if we actually were in the virtual world even though we know there is nothing there. In their handbook of Virtual Reality, Burdea and Coiffet (Virtual reality technology, Wiley, New York, 2003) suggested that the experience of presence in IVR would emerge from the combination of three Is: Immersion or capacity to isolate from the external world, Interaction or capacity to naturally exploring the virtual environment, and Imagination or individual aptitudes with mental imagery. So far, several studies have investigated the technological and psychological factors affecting the degree of immersion and interaction. However, no study has explored the relationship between perceived presence and mental imagery. Here we aim at filling this gap through a correlational study comparing self-reports about sense of presence and mental imagery abilities. After experiencing two IVR scenarios (an art gallery and a living room), 142 male and female users were administered with questionnaires assessing the degree of presence (Igroup Presence Questionnaire), the degree of vividness (Vividness of Visual Imagery Questionnaire) and control (Test of Visual Imagery Control) of subjective mental images. Results showed a clear positive correlation between presence and vividness: the higher the vividness of mental images the stronger the reported sense of presence felt in IVR scenarios. Instead, the capacity to control mental imagery showed a weaker association with presence. We may conclude that individual differences in the degree of perceived presence and mental imagery ability are associated.

[Pilot study: Apricena Marble District quarry workers and COPD]. / Studio pilota: addetti alle cave di pietra nel distretto del Marmo di Apricena e BPCO.

The aim of the present article was to verify the Chronic Obstructive Pulmonary Disease (COPD) prevalence in a cohort of quarry workers who belong to the Apricena Marble District. We studied 70 workers. They received a questionnaire about the disease and confounding factors. The spirometry showed that the FEV1 was normal in 95% of workers, instead 5% showed values lower than former (Average: 73%). TNF alpha and IL-1 Beta in Exhaled breath condensate (EBC) were lower than the method limit in all workers. Our cohort is limited, but we could retain that the lung disease is not present in workers taken into consideration. Our results are in according to Rushton who demonstrated that only a prolonged occupation, higher than thirty years, is able to induce lung disease.

Psychrophilic superoxide dismutase from Pseudoalteromonas haloplanktis: biochemical characterization and identification of a highly reactive cysteine residue.

A psychrophilic superoxide dismutase (SOD) has been characterized from the Antarctic eubacterium Pseudoalteromonas haloplanktis (Ph). PhSOD is a homodimeric iron-containing enzyme and displays a high specific activity, even at low temperature. The enzyme is inhibited by sodium azide and inactivated by hydrogen peroxide; it is also very sensitive to peroxynitrite, a physiological inactivator of the human mitochondrial Mn-SOD. Even though PhSOD is isolated from a cold-adapted micro-organism, its heat stability is well above the maximum growth temperature of P. haloplanktis, a feature common to other Fe- and Mn-SODs. The primary structure of PhSOD was determined by a combination of mass spectrometry and automated Edman degradation. The polypeptide chain is made of 192 amino acid residues, corresponding to a molecular mass of 21251 Da. The alignment with other Fe- and Mn-SODs showed a high amino acid identity with Fe-SOD from Vibrio cholerae (79%) and Escherichia coli (70%). A significant similarity is also shared with human mitochondrial Mn-SOD. PhSOD has the unique and highly reactive Cys57 residue, located in a variable region of the protein. The three-dimensional model of the PhSOD monomer indicates that Cys57 is included in a region, whose structural organization apparently discriminates between dimeric and tetrameric SODs. This residue forms a disulfide adduct with beta-mercaptoethanol, when this reducing agent is added in the purification procedure. The reactivity of Cys57 leads also to the formation of a disulfide bridge between two PhSOD subunits in specific denaturing conditions. The possible modification of Cys57 by physiological thiols, eventually regulating the PhSOD functioning, is discussed.

Partial purification and MALDI-TOF MS analysis of UN1, a tumor antigen membrane glycoprotein.

UN1 is a membrane glycoprotein that is expressed in immature human thymocytes, a subpopulation of peripheral T lymphocytes, the HPB acute lymphoblastic leukemia (ALL) T-cell line and fetal thymus. We previously reported the isolation of a monoclonal antibody (UN1 mAb) recognizing the UN1 protein that was classified as "unclustered" at the 5th and 6th International Workshop and Conference on Human Leukocyte Differentiation Antigens. UN1 was highly expressed in breast cancer tissues and was undetected in non-proliferative lesions and in normal breast tissues, indicating a role for UN1 in the development of a tumorigenic phenotype of breast cancer cells. In this study, we report a partial purification of the UN1 protein from HPB-ALL T cells by anion-exchange chromatography followed by immunoprecipitation with the UN1 mAb and MALDI-TOF MS analysis. This analysis should assist in identifying the amino acid sequence of UN1.

[Descriptive statistics of occupational accidents during 2005 in the area of competency of the Occupational Health Unit FG/1]. / Statistica descrittiva degli infortuni sul lavoro avvenuti nel corso del 2005 nel territorio di competenza della ASL FG/1.

During 2005, the Unit of Occupational Health of the Local Health Centre FG/1 started to record accident at work. The results confirme "Industry" as the sector with the highest risk of accidents at work. Many accidents at work seem to be in relation with the insufficient use of D.P.I. or with the wrong use of D.P.I. The results point out the necessity of a better model to record data and in particular the data that describe what/how has the accident happened and the sector/subsector of workers. In order to continue this activity during the next years, it will be useful to control the trend.

Resistance of archaebacterial aEF-1 alpha.GDP against denaturation by heat and urea.

The elongation factor aEF-1 alpha, isolated as aEF-1 alpha.GDP from the thermoacidophilic archaebacterium Sulfolobus solfataricus, exchanges GDP for [3H]GDP at a rate which reaches a maximum at 95 degrees C. The rate constants at different temperatures of the heat inactivation of aEF-1 alpha.GDP are considerably lower compared to those referred to Escherichia coli EF-Tu.GDP. The Tm values determined for both aEF-1 alpha.GDP and EF-Tu.GDP are 97 and 53 degrees C, respectively. The addition of GDP during the heat treatment protects significantly EF-Tu.GDP but only slightly aEF-1 alpha.GDP. The ability of aEF-1 alpha.GDP to exchange GDP for [3H]GDP is impaired at 70 degrees C by urea at concentrations which are greater compared to those required to inactivate E. coli EF-Tu.GDP at 45 degrees C; apparently both factors are not protected by GDP against inactivation by urea.

Molecular, functional and structural properties of an archaebacterial elongation factor 2.

The elongation factor 2 (aEF-2) from the extreme thermo-acidophilic archaebacterium Sulfolobus solfataricus, is the only cytosolic target protein which is ADP-ribosylated by diphtheria toxin in presence of NAD. Once ADP-ribosylated, aEF-2 is no longer able to sustain poly(Phe) synthesis in vitro. aEF-2 displays a great thermoresistance: at the growth temperature of the archaebacterium, 87 degrees C, its half-life is 3 h. The amino acid sequence of the N-terminal region of aEF-2 has been determined up to residue 22. In the first 15 positions such a sequence is identical to that of EF-2 from Sulfolobus acidocaldarius and very similar to that of EF-2 from other archaebacteria or eukaryotes. The same is true for the primary structure of the peptide containing the ADP-ribosylation site. The fact that the primary structure of EF-2 at the ADP-ribosylation site is highly conserved ensures either the correct recognition of the histidine residue by the enzymes involved in its modification to diphthamide, or the proper interaction with the diphtheria toxin.

Iron superoxide dismutase from the archaeon Sulfolobus solfataricus: average hydrophobicity and amino acid weight are involved in the adaptation of proteins to extreme environments.

The iron-superoxide dismutase in the thermoacidophilic archaeon Sulfolobus solfataricus has a homodimeric structure with a metal content of 0.7 atom of iron per subunit. The enzyme is insensitive to cyanide inhibition, sensitive to inactivation by H2O2 and is the most heat resistant SOD known so far being its half-life 2 h at 100 degrees C. Its primary structure was determined by a profitable combination of advanced mass spectrometry and automated sequence analysis of peptides obtained after cleavage of the purified protein. The enzyme subunit is composed of 210 amino acid residues accounting for a relative molecular mass of 24,112. It does not contain cysteine residues and has a high average of both hydrophobicity and amino acid weight. Vice versa, the hydrophobicity is lower in halophilic SODs. Therefore, it seems that the average hydrophobicity is involved in the adaptation of proteins to extreme environments. The multiple alignment of the primary structure of archaeal and thermophilic eubacterial SODs indicated that archaeal SODs evolved separately from the thermophilic eubacterial SODs and that halophiles originated from a gene different from that of thermophilic archaea.

Archaeal elongation factor 1 beta is a dimer. Primary structure, molecular and biochemical properties.

The elongation factor 1 beta (EF-1 beta), that in eukarya and archaea promotes the replacement of GDP by GTP on the elongation factor 1 alpha x GDP complex, was purified to homogeneity from the thermoacidophilic archaeon Sulfolobus solfataricus (SsEF-1 beta). Its primary structure was established by sequenced Edman degradation of the entire protein or its proteolytic peptides. The molecular weight of SsEF-1 beta was estimated as about 10000 or 20000 under denaturing or native conditions respectively; this finding suggests that the native protein exists as a dimer. The peptide chain of SsEF-1 beta is much shorter than that of its eukaryotic analogues and homology is found only at their C-terminal region; no homology exists between SsEF-1 beta and eubacterial EF-Ts. At 50 degrees C, at a concentration of SsEF-1 beta 5-fold higher than that of SsEF-1 alpha x [3H]GDP the rate of the exchange of [3H]GDP for GTP becomes about 160-fold faster. An analysis of the values of the energetic parameters indicates that in the presence of SsEF-1 beta the GDP/GTP exchange is entropically favoured. At 100 degrees C the half-life of SsEF-1 beta is about 4 h.

Breast cancer diagnosed during pregnancy and lactation: biological features and treatment options.

AIM OF THE STUDY: Assessment of biological features and treatment of patients with breast cancer presenting during pregnancy or lactation. PATIENTS AND METHODS: Immunohistochemical analysis of estrogen receptor (ER) and progesterone receptor (PgR), Ki-67, HER2/neu, prognostic markers, treatment and follow-up of 21 patients with breast cancer during pregnancy (BCdP) and 17 with breast cancer during lactation (BCdL) are presented. RESULTS: Median age was 36 and 33 years, median tumour size was 2.4 and 2.5 cm, axillary lymph nodes were positive in 10 of 21 pregnant patients and 11 of 17 lactating patients, respectively. Both ER and PgR were not expressed in six of 21 pregnant women and nine of 17 lactating patients. All the six women who had concurrent diagnosis of breast cancer and pregnancy (first trimester) preferred termination of pregnancy although an alternative option was discussed. Five patients received anthracycline containing chemotherapy during the second and third trimester with no complications for patient and child. Conservative surgery was performed in 15 of 21 patients during pregnancy with no local reappearance after a median follow-up of 24 months. Three pregnant women underwent lymphoscintigraphy and sentinel lymph node biopsy. CONCLUSIONS: Patients who had concurrent diagnosis of breast cancer and pregnancy (early first trimester) preferred termination of pregnancy to allow easier completion of treatment. Conservative surgery was safe also in women with BCdP. Sentinel node biopsy might be considered for pregnant patients with a clinically negative axilla.

Cloning and sequencing of the gene encoding thermostable elongation factor 2 in Sulfolobus solfataricus.

The gene (aEF-2) coding for the translation elongation factor 2 (aEF-2) in the thermoacidophilic archaebacterium, Sulfolobus solfataricus, has been cloned and sequenced. The deduced primary structure of aEF-2 is composed of 735 amino acids (aa), excluding the Met start residue. There are no Cys residues and the calculated M(r) is 81,699. In the coding region of aEF-2, the high A + T content greatly influences the codon usage. From the alignment of the primary structure of aEF-2 with that of the analogous factors from the three kingdoms, aa identities were derived. The greatest identity (82%) was found with EF-2 from Sulfolobus acidocaldarius; lower values were observed with other archaebacterial EF-2 (45-47%), eukaryotic EF-2 (38-40%) and with the functional eubacterial analogue EF-G (28-31%). aEF-2 possesses the consensus sequences required for a GTP-binding protein and the four regions which are supposed to be involved in the functional regulation of EF-2/EF-G. These data should have phylogenetic implications.

The interaction between the archaeal elongation factor 1alpha and its nucleotide exchange factor 1beta.

In Sulfolobus solfataricus the binding of the exchange factor 1beta (SsEF-1beta) to SsEF-1alpha-GDP displaces the nucleotide and the SsEF-1alpha-SsEF-1beta complex is formed. The complex itself is stable, but it dissociates upon the addition of GDP or Gpp(NH)p but not ATP. Since the rate of the formation of the SsEF-1alpha-SsEF-1beta complex is significatively slower than the rate of the nucleotide exchange catalyzed by SsEF-1beta it can be inferred that in vivo the GDP/GTP exchange reaction proceeds via an SsEF-1alpha-SsEF-1beta interaction without involving the formation of a stable binary complex as an intermediate.

The site for GTP hydrolysis on the archaeal elongation factor 2 is unmasked by aliphatic alcohols.

An appropriate mixture of ethylene glycol and BaCl2 enhanced the otherwise very low intrinsic GTPase activity of the elongation factor 2 isolated from the archaeon Sulfolobus solfataricus (SsEF-2). The enzymatic activity became up to 300-fold higher than that of the SsEF-2 GTPase measured in the absence of any stimulator, but remained 20-fold lower than that stimulated by ribosome. The stimulatory effect of ethylene glycol/Ba2+ was attributed to the increased affinity for GTP, probably related to a conformational change occurring in a hydrophobic region near the catalytic site.

A 35 kDa NAD(P)H oxidase previously isolated from the archaeon Sulfolobus solfataricus is instead a thioredoxin reductase.

A thioredoxin reductase (TrxR) has been identified in the hyperthermophilic archaeon Sulfolobus solfataricus (Ss). This enzyme is a homodimeric flavoprotein that was previously identified as NADH oxidase in the same micro-organism ('Biotechnol. Appl. Biochem. 23 (1996) 47'). The primary structure of SsTrxR is made of 323 amino acid residues and contains two putative betaalphabeta regions for the binding of FAD, and a NADP(H) binding consensus sequence in the proximity of a CXXC motif. These findings indicate that SsTrxR is structurally related to the class II of the pyridine nucleotide-disulphide oxidoreductases family. Moreover, the enzyme exhibits a NADP(H) dependent thioredoxin reductase activity requiring the presence of FAD. Surprisingly, the reductase activity of SsTrxR is reduced in the presence of a specific inhibitor of mammalian TrxR. This finding demonstrates that the archaeal enzyme, although structurally related to eubacterial TrxR, is functionally closer to eukaryal enzymes. Experimental evidences indicate that a disulphide bridge is required for the reductase but also for the NADH oxidase activity of the enzyme. These results are further supported by the significantly reduced activities exerted by the C147A mutant. The integrity of the CXXC motif is also involved in the stability of the enzyme.

Protein engineering on enzymes of the peptide elongation cycle in Sulfolobus solfataricus.

The present article is a review of the work done on the elongation factors EF-1 alpha, EF-2 and EF-1 beta isolated from the hyperthermophilic archaeon Sulfolobus solfataricus. The molecular, physical and biochemical properties of the intact, truncated, mutant or chimeric forms are described and compared.

Myofibrosarcoma of the breast: review of the literature on myofibroblastic tumors and criteria for defining myofibroblastic differentiation.

A case of myofibrosarcoma of the breast is described. A 55-year-old woman presented with a small mammary nodule. A large recurrent lesions appeared a month later, and the patient died 11 months following initial presentation from diffuse pleuropulmonary metastases. Histologically, the primary tumor consisted mainly of spindled cells, arranged in fascicles and surrounded by varying quantities of dense hyaline collagen. The recurrent lesion had a more pleomorphic organization. In both lesions, there was positive immunostaining for vimentin, smooth-muscle actin, and fibronectin, and negative results for desmin, laminin, and type IV collagen. Electron microscopy revealed abundant rough endoplasmic reticulum, myofilaments with focal densities, and the fibronexus junctions and fibronectin fibrils characteristic of myofibroblasts. Given these cellular features and behavior, the tumor was interpreted as a malignant neoplasm showing myofibroblastic differentiation, i.e., a myofibrosarcoma. This case enlarges the group of myofibrosarcoma of breast, also with the demonstration of fibronexus and fibronectin fibrils. The paper emphasizes the criteria required for myofibroblastic differentiation and reviews lesions of the breast reported in the literature as myofibroblastic.

Properties of the purified elongation factor 2 in the thermoacidophilic archaebacterium Sulfolobus solfataricus.

The elongation factor 2 (aEF-2) has been purified to homogeneity from the extreme thermoacidophilic archaebacterium Sulfolobus solfataricus. It is the only target protein which is ADP-ribosylated by diphtheria toxin in presence of NAD and this modification abolishes its property to support poly(Phe) synthesis in vitro. The factor is constituted by a single polypeptide chain with a relative molecular mass of 78,000 and an isoelectric point of 5.9. aEF-2 is resistant to heat denaturation as shown by the fact that its capability to be ADP-ribosylated was only 10% reduced after 4 h treatment at 80 degrees C. Its amino acid composition does not reveal significant differences with that of analogous factors in other sources; nevertheless, the deviation function indicates that aEF-2 is related to Sulfolobus acidocaldarius and eukaryotes EF-2 more than to eubacterial EF-G or other archaebacterial EF-2.

Cardiopulmonary exercise test in young women affected by anorexia nervosa.

BACKGROUND: The aim of this study was to evaluate exercise performance in patients affected by anorexia nervosa. METHODS: We studied 19 patients (all females, mean age 23.1 +/- 5.2 years) affected by anorexia nervosa (mean weight 37.3 kg, body mass index 14.04 +/- 1.4 kg/m2) and 20 constitutionally thin women, matched for age, height and physical activity, with a body mass index < 19 kg/m2. All these women underwent clinical examination, standard ECG and a cardiopulmonary stress test. RESULTS: Patients affected by anorexia nervosa showed a lower heart rate and systolic blood pressure at peak exercise (148.8 +/- 13.8 vs 171 +/- 9.2 b/min, p < 0.001, and 130 +/- 9.5 vs 152 +/- 11.2 mmHg, p < 0.001), work load (85.5 +/- 15.1 vs 117.2 +/- 20.3 W, p < 0.001), rate-pressure product (19 371 +/- 2391 vs 25,986 +/- 2218 b/min/mmHg, p < 0.001), oxygen uptake (VO2) at rest and maximum VO2 (5.4 +/- 1.7 vs 7.1 +/- 1.1 ml/kg/min, p < 0.001, and 28.08 +/- 6.3 vs 40.2 +/- 7.1 ml/kg/min, p < 0.001), anaerobic threshold (15.7 +/- 1.9 vs 20.4 +/- 2.1 ml/kg/min, p < 0.001), VO2 during exercise (9.5 +/- 1.2 vs 12.8 +/- 1.3 ml/min/W, p < 0.001), maximum minute ventilation (34.5 +/- 9.9 vs 48.4 +/- 10.3 /min, p < 0.001), and oxygen pulse (7.2 +/- 2 vs 10.9 +/- 2.4 ml/b, p < 0.001). CONCLUSIONS: These data show an abnormal working capacity and cardiovascular responses to exercise in patients affected by anorexia nervosa. The low VO2, both at rest and during exercise, allows them to maintain a relatively high level of physical activity, which contributes to increase the energy expenditure needed for weight loss.

Tracheobronchial involvement in 84 cases of pulmonary tuberculosis.

In suspected pulmonary tuberculosis (TB), tracheobronchial examination is required for patients with clinical and radiographic features consistent with tuberculosis disease but with negative sputum for Mycobacterium tuberculosis. We report the endoscopic findings of 84 patients who underwent fibreoptic bronchoscopy in recent years, and whose cultures of biological specimens grew M tuberculosis. Cough (86%) and fever (69%) were the most common symptoms, followed by sputum (67%), dyspnoea (30%) and haemoptysis (27%). Chest radiographic abnormalities were mostly localized (60%) with prevalence in the upper lobes; in two cases chest radiography was normal. Sixty two patients (74%) showed endoscopic abnormalities: 1) mucosal inflammation; 2) submucosal granulomas and polyps; and 3) stenoses. They were localized in 58% of patients and diffuse in 42%. Five patients were checked several times during the year following the diagnosis because of a high degree of tracheobronchial involvement. Only one subject recovered, whilst in the other four stenotic sequelae were found. Fibreoptic bronchoscopy confirmed its usefulness in the diagnosis of tuberculosis and in monitoring the course and the outcome of the bronchial tuberculosis involvement.

[Considerations about health risk management]. / Riflessioni sul risk management in sanità.

From the birth of doctrines of Risk Management to today a lot of time is passed. From the initial application in the field of the insurances and the management of the enterprises, theories inspired to the identification, evaluation and correction of connected risks to the activity and the industrial trial has been figurative to the health, field in which the application of these principles results to be how much never profit and productive of benefits above all for the patients that suffer consequences of errors but also for the physicians and the personnel that, perfectly inserted in an organization aware of the trials to put into effect, can bring their contribution to underline the weak points of the relief trial. The economic cost and consequences of errors can decrease if a new culture is established inspired to the learning and the communication of the adverse events, to minimize the possibility that they again occurs.