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Impact and compression-after-impact (CAI) tests were carried out on [02/ ± 45]s carbon/epoxy samples to characterize the effect of z-pinning on the delamination resistance and damage tolerance properties of the laminate. Unpinned and z-pinned samples were subjected to impacts between 2 and 36 J to produce damage conditions that extend from barely visible impact damage (BVID) to complete penetration. The damage induced by impact and the damage modes leading to ultimate CAI failure were examined by X-radiography and by direct observations of the sample faces during CAI loading. The analyses indicate that the role of z-pins on the impact and CAI response of the laminate is dependent on the size and features of the damage. Z-pins do not modify the structural response to impact of the laminate, but they are effective in reducing the extent of damage for impact energies above a threshold value. Z-pinning is also effective in improving the CAI strength of the laminate for impact energies above this threshold value, even though it degrades the residual compressive strength for lower impact energies. Reductions in impact delamination size of up to 50% and improvements in CAI strength of about 20% were achieved by z-pinning for high-energy impacts. The mechanisms by which the z-pins affect the CAI response of the samples are illustrated and examined in detail for different impact damage severities.

In the past few decades, the need for efficient and reliable Structural Health Monitoring strategies has led to the development of several approaches for damage detection and characterization purposes. Among them, the Nonlinear Vibro-Acoustic Modulation (VAM) exploits the modulation arising from the interaction of two concurrently applied driving waves, namely the probe and the pump excitations, in the presence of nonlinear scatters such as cracks and defects. Therefore, the VAM provides information on the emergence of internal damage by extracting the nonlinear modulated components of the response of a damaged system. Originally proposed for granular media, the method has shown to be effective in detecting the presence of defects also in metals and composite materials. Nonetheless, its efficacy is highly affected by the excitation frequencies, which are usually chosen among the system resonances. The need for a preliminary modal analysis and, at once, the risk of selecting pump-probe frequency combinations with low sensitivity to damage may make the procedure time-consuming and not fully reliable, preventing the VAM technique from being widely accepted as a robust monitoring tool. To overcome these limitations, a broadband excitation may be used. This study assesses the effectiveness of the VAM technique when a combination of a frequency-swept pump excitation and a mono-harmonic probe wave is applied to drive the sample. Experimental tests were conducted on a composite laminated beam mounted on an electrodynamic shaker and tested in both pristine and damaged conditions. Low-profile surface-bonded piezoceramic transducers were used for both probe excitation and sensing. Barely visible impact damage (BVID) was introduced in the composite beam to examine the potential of the approach for the detection of very small, localized damage. The results show that the use of VAM with a broadband low-frequency excitation may be an effective option for identifying nonlinearities associated with typical damage occurring in composite structures.

Composite materials provide many advantages over more conventional materials. However, their susceptibility to impact damage can question their use in critical load-bearing structures, and efficient methods are needed for early damage detection. To this purpose, the nonlinear vibro-acoustic modulation (VAM) technique applies a low-frequency pump excitation and a high-frequency probe excitation to exploit the onset of harmonic components around the probe frequency of the damaged structural response. The VAM technique has been widely studied on structures instrumented with piezoceramic transducers used for both actuation and sensing, but few attempts have been made to use equipment typical of modal testing, such as shakers and accelerometers. In this study, the VAM technique is applied to a composite laminate beam by employing an electro-dynamic shaker to generate low-frequency flexural excitation, a low-profile piezoceramic transducer to introduce the probe wave, and a micro-accelerometer to sense the structural response. Three resonance low frequencies and two acoustic frequencies are considered in different testing scenarios, at increasing levels of excitation amplitude. The results show a general good performance of the technique with the adopted experimental setup, the choice of the probe frequency and the higher level of the pump excitation having a significant impact on its sensitivity.

Pseudoangiomatous stromal hyperplasia (PASH) is an uncommon benign mesenchymal breast lesion. There are extremely rare reports of PASH arising in accessory breast tissue. To date, in literature, fewer than 10 cases of PASH occurring in axillary region have been described. We report a case presenting as axillary lump in a young woman. A 20-year-old female presented to our surgical unit for a progressively growing and painful palpable mass of the right axilla for about a year. Before surgery an ultrasound was performed. The patient underwent local excision of the lesion under local anaesthesia. Through histological and immunohistochemical examination a pseudoangiomatous stromal hyperplasia (PASH) was diagnosed. At 6 months of followup the patient is free of disease. It is important to include PASH also in the differential diagnosis of axillary lumps. Histological examination of the surgical specimen and surgery represent, respectively, the mainstay for diagnosis and therapy.

The Investigations of this article focus on the response of an Al2O3:C radioluminescence (RL) prototype for medical dosimetry in a 6 MV photon beam. The prototype can be configured using two types of detectors coupled to fiber-optic cables - single crystal (1 x 1 x 2 mm(3)) and droplets (in two grain sizes, 38 and 4 mu m, molded in r =0.5 mm,1= 200 mu m). By using the appropriate filters in addition to time gating it is possible to remove disturbance present during irradiation: the stem effect. Pre -irradiation of the dosimeters to a dose of 300 Gy made the memory effects in Al2O3:C negligible, so as to not impair the dosimetric properties of the system. The key findings are that the system is suitable for small field beam dosimetry, while giving overall good dose response in other features (i.e., beam profile, dose rate - FF and FFF modes). The results show that our prototype can be used for real time dose rate assessment in medical photon dosimetry without many correction factors. The 41 mu m RL measurement results are in excellent agreement (i.e. below 1%) with the dose delivered according to standard beam data. (C) 2018 Elsevier B.V. All rights reserved.

The spread of infections from multi-resistant bacteria in hospitals around the world is raising at an alarming rate. With the increasing capacity of bacteria to develop resistance to traditional antibiotics that target a particular metabolic pathway inside the cell, the use of nanoparticles as therapeutic agents is gaining importance because of their ability to attack bacterial membranes without evoking resistance. We have synthesized the catanionic surfactants Coum12–Coum18, based on fluorescent lactose-derivative organic salts using low-cost starting materials. In water, they self-assemble spontaneously to form stable aggregates at a physiological pH. The antibacterial properties of Coum12–Coum18 were investigated towards multi-drug-resistant Gram-positive bacteria (Staphylococcus aureus and Enterococcus faecalis) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). Compound Coum18 was found to have both a bacteriostatic and a bactericidal activity towards Gram-positive bacteria, although the values of both the MIC and MBC (32 μg mL−1) suggest only a topical use of the molecule. The valuable results that were found provide a challenging task for further investigation aimed at the development of this class of antibacterial drugs. In vitro fluorescence microscopy gave insight into the interaction between the aggregates and the cellular membranes on HeLa and CHO cells.

In this work, a multi-technical bulk and surface analytical approach was used to investigate the bioleaching of a pyrite and arsenopyrite flotation concentrate with a mixed microflora mainly consisting of Acidithiobacillus ferrooxidans. X-ray diffraction, X-ray photoelectron spectroscopy (XPS) and X-ray-induced Auger electron spectroscopy mineral surfaces investigations, along with inductively coupled plasma-atomic emission spectroscopy and carbon, hydrogen, nitrogen and sulphur determination (CHNS) analyses, were carried out prior and after bioleaching. The flotation concentrate was a mixture of pyrite (FeS(2)) and arsenopyrite (FeAsS); after bioleaching, 95% of the initial content of pyrite and 85% of arsenopyrite were dissolved. The chemical state of the main elements (Fe, As and S) at the surface of the bioreactor feed particles and of the residue after bioleaching was investigated by X-ray photoelectron and X-ray excited Auger electron spectroscopy. After bioleaching, no signals of iron, arsenic and sulphur originating from pyrite and arsenopyrite were detected, confirming a strong oxidation and the dissolution of the particles. On the surfaces of the mineral residue particles, elemental sulphur as reaction intermediate of the leaching process and precipitated secondary phases (Fe-OOH and jarosite), together with adsorbed arsenates, was detected. Evidence of microbial cells adhesion at mineral surfaces was also produced: carbon and nitrogen were revealed by CHNS, and nitrogen was also detected on the bioleached surfaces by XPS. This was attributed to the deposition, on the mineral surfaces, of the remnants of a bio-film consisting of an extra-cellular polymer layer that had favoured the bacterial action.

In this work, the microbe-mediated oxidative dissolution of enargite surfaces (Cu(3)AsS(4)) was studied on powdered samples exposed to 9K nutrient solution (pH 2.3) inoculated by Acidithiobacillus ferrooxidans initially adapted to arsenopyrite. These conditions simulate the acid mine environment. The redox potential of the inoculated solutions increased up to +0.72 V vs normal hydrogen electrode (NHE), indicating the increase of the Fe(3+) to Fe(2+) ratio, and correspondingly the pH decreased to values as low as 1.9. In the sterile 9K control, the redox potential and pH remained constant at +0.52 V NHE and 2.34, respectively. Solution analyses showed that in inoculated medium Cu and As dissolved stoichiometrically with a dissolution rate of about three to five times higher compared to the sterile control. For the first time, X-ray photoelectron spectroscopy (XPS) was carried out on the bioleached enargite powder with the aim of clarifying the role of the microorganisms in the dissolution process. XPS results provide evidence of the formation of a thin oxidized layer on the mineral surface. Nitrogen was also detected on the bioleached surfaces and was attributed to the presence of an extracellular polymer substance layer supporting a mechanism of bacteria attachment via the formation of a biofilm a few nanometers thick, commonly known as nanobiofilm.

A feasibility study for the use of a Ce3+-doped optical fibre as a radio luminescent dosimeter in radiotherapy was carried out. The prototype showed a satisfactory reproducibility (1.7%) and a good linearity over a clinically relevant dose range (from few cGy to approximately 10 Gy). Moreover, the device enabled a reliable evaluation of the absorbed dose, independently of the dose rate and of the orientation of the incoming radiation. A slight energy dependence of the response was observed when the system was irradiated with electron beams of different energies. The results indicate that the employment of this new system might be very promising both for quality control measurements and "in vivo" dosimetry. Some improvements are nevertheless still required in order to allow a real-time evaluation of the Cherenkov radiation produced by the irradiated portion of the passive optical fibre, which influences some of the dosimetric properties of the system. (c) 2006 Elsevier B.V. All rights reserved.

In this paper, errors and discrepancies in the subject paper [Cincotti et al. (2002)] are highlighted. A comment, concerning the axial resolution associated to the adopted processing procedure is also reported.

A novel series of 1-[2-(diarylmethoxy)ethyl]-2-methyl-5-nitroimidazole (DAMNI) analogues were synthesized and tested in cell-based assays and in enzyme assays against HIV-1 recombinant reverse transcriptase (RT). Preparation of the new derivatives was performed by reacting the appropriate benzhydrols or the corresponding bromides with 1-(2-hydroxyethyl)-2-methyl-5-nitroimidazole or the 3-hydroxypropyl homologue. Several compounds showed anti-HIV-1 activity in the submicromolar range. Structure-activity relationship studies suggested that meta substitution at one phenyl ring of the diarylmethane moiety strongly influences the antiviral activity. The 3,5-disubstitution at the same phenyl ring led to less potent derivatives. Molecular modeling and docking studies within the RT non-nucleoside binding site confirmed that DAMNIs, similar to other NNRTIs such as TNK-651 and delavirdine (BHAP U90152), assume a butterfly-like conformation that appears to be halfway between that of classical NNRTIs, such as nevirapine, HEPT, TBZ, TIBO, and DABOs, and the conformation of BHAPs. In particular, the diphenylmethane moiety mimics the wings whereas the 1-(2-methyl-5-nitroimidazolyl)ethane portion resembles the BHAP 5-methanesulfonamidoindole-2-carbonylpiperazine portion.

To the Editor: Streptococcus suis, a major swine pathogen worldwide, is emerging as a zoonotic agent capable of causing a variety of serious infections in swine as well as in persons exposed to pigs or to pork products. These infections include meningitis, septicemia, pneumonia, endocarditis, arthritis, and septic shock (1,2). Despite recent outbreaks among persons in China, S. suis disease in humans is a rare, probably underdiagnosed infection that usually occurs as sporadic cases (1,2). Persons in close occupational or accidental contact with pigs or pork products and those who eat uncooked or undercooked pork may be at higher risk than others. However, most infected persons are likely healthy carriers, and S. suis is believed to induce overt disease (especially meningitis) in only some circumstances (2). We describe a case of S. suis meningitis in a 68-year-old man from Sardinia, Italy, who had no reported contact with swine, other animals, or any animal products; the patient also had cancer, which was discovered incidentally during the workup. In November 2007, the patient was hospitalized with a 48-hour history of fever, headache, nausea, and general malaise. Physical examination showed impaired consciousness, nuchal rigidity, and a temperature of 39.5°C. Laboratory findings were 20,700 leukocytes/mm3 with 92% neutrophils, glucose 95 mg/dL, and C-reactive protein 375 mg/L. Cerebrospinal fluid (CSF) analysis demonstrated 240 leukocytes/μL with 80% polymorphonuclear cells, glucose 24 mg/dL, and protein 277 mg/dL. A computed tomography scan of the head showed no abnormal findings. Gram stain of CSF showed gram-positive cocci, mostly in pairs (Figure). Figure Gram-positive cocci, mostly in pairs, in cerebrospinal fluid from a 68-year-old man with Streptococcus suis meningitis. Magnification ×1,000. Empirical therapy consisted of intravenous ceftriaxone (2 g twice a day) and oral chloramphenicol (2 g once a day). On day 5, α-hemolytic streptococci were isolated from CSF on sheep blood agar and identified as S. suis by using APIStrep (bioMerieux, Marcy l’Etoile, France). Serotyping, performed by slide agglutination with specific antiserum (Statens Serum Institute, Copenhagen, Denmark), identified the isolate as serotype 2. Antimicrobial drug­­–susceptibility testing, performed according to guidelines of the Clinical and Laboratory Standards Institute (www.clsi.org), indicated susceptibility to penicillin, ceftriaxone, chloramphenicol, levofloxacin, and vancomycin and resistance to erythromycin (MIC >128 mg/L) and tetracycline (MIC 16 mg/L). Erythromycin resistance was constitutive and was mediated by the erm(B) determinant; tetracycline resistance was mediated by tet(W). Multilocus sequence typing (http://ssuis.mlst.net) assigned the S. suis isolate to sequence type (ST) 1. The patient, a retired welder, denied any recent occupational or even occasional contact with swine or other animals and had no history of eating raw or undercooked pork. The patient’s condition improved; chloramphenicol was discontinued on day 10, but the 14-day course of ceftriaxone was completed. On day 6, the patient became afebrile but had dizziness and deafness; a formal audiology evaluation on day 9 showed severe bilateral sensorineural high-frequency hearing loss (–80 dB) that improved after a short course of dexamethasone. However, the patient was not discharged because of the lung mass found on initial chest radiograph. Computed tomography scan, bronchoscopy, and histopathologic findings led to diagnosis of the mass as an advanced-stage squamous cell carcinoma. The meningitis had common and uncommon features. The common features were hearing loss, a typical outcome of S. suis meningitis independent of early antimicrobial drug administration (1,2); serotype 2, the most frequent and virulent serotype in swine and in humans (1,2); ST1, belonging to the ST1 complex, strongly associated with S. suis meningitis isolates (2,3); and erm(B)-mediated erythromycin resistance, widespread in this species (4). The uncommon features were tetracycline resistance mediated by tet(W), increasingly detected in gram-positive and in gram-negative bacteria (5) but never previously reported in S. suis or in other major streptococcal pathogens, where common determinants are tet(M) and tet(O); and lack of evidence for recent contact with swine, other animals, or swine (pork) products. Two previous cases of human S. suis meningitis in Italy (6,7) and other recent cases from Europe (8,9) were related to occupational exposure. However, the patient reported here also had cancer, and malignancy has been indicated as a predisposing factor for the development of severe S. suis disease in humans (2). These findings appear to be consistent with the recent suggestion of new epidemiologic patterns of infection caused by this organism (2). S. suis may become an opportunistic pathogen in persons who are under stress or who have immunodeficiency, and it has been increasingly isolated from mammalian species other than pigs, from birds, and from the environment. As also discussed in a recent survey (10), the possibility cannot be excluded that a patient with S. suis infection may be unaware or have no memory of previous exposure to animals. Alternatively, because asymptomatic carriage of S. suis has been documented in humans (2) and is believed to contribute to its transmission (10), the possibility should also be considered that the infection may be a reactivation, possibly favored by malignancy, of latently colonizing S. suis.

The Mycobacterium fortuitum group of rapidly growing nontuberculous mycobacteria is an uncommon cause of renal infection, particularly in otherwise healthy hosts. We describe a case of nephritis due to M. fortuitum in an immunocompetent woman with a clinical and radiological diagnosis of renal tuberculosis.

Among a series of unmodified phosphodiester (PO)-oligodeoxynucleotides (PO-ODNs) complementary to some of the human immunodeficiency virus type 1 (HIV-1) regulatory genes, several PO-ODN sequences complementary to the vpr gene (PO-ODNs-a-vpr, where a-vpr is the antisense vpr sequence) emerged as potent inhibitors (at concentrations of 0.8 to 3.3 microM) of HIV-1 multiplication in de novo infected MT-4 cells, while they showed no cytotoxicity for uninfected cells at concentrations up to 100 microM. Unlike phosphorothioate counterparts, PO-ODN-a-vpr sequences were not inhibitory to HIV-2 multiplication in de novo infected C8166 cells and neither prevented the fusion between chronically infected and bystander CD4+ cells nor inhibited the activity of the HIV-1 reverse transcriptase in enzyme assays. Moreover, they were not inhibitory to HIV-1 multiplication in chronically infected cells. Delayed addition experiments showed that PO-ODNs-a-vpr inhibit an event in the HIV-1 replication cycle following adsorption to the host cell, but preceding reverse transcription. Structure-activity relationship studies indicated that the antiviral activity of the test PO-ODN-a-vpr sequences is not related to an antisense mechanism but to the presence, within the active sequences, of contiguous guanine residues. Physical characterization of the test PO-ODNs suggested that the active structure is a tetramer stabilized by G quartets (i.e., four G residues connected by eight hydrogen bonds).

A new, simple extrapolation technique to enhance the lateral resolution of pulse-echo imaging systems is presented. The method attempts to build an image that could be obtained with a transducer aperture larger than that physically available, extrapolating the information contained in the image to be enhanced. The extrapolation process requires small hardware modifications of the standard echographic systems. The computational cost is very low compared with Fourier-based deconvolution approaches. The obtained computer simulations give very interesting and promising results.

Ultrasound beams propagating in biological tissues undergo distortions due to local inhomogeneities of the acoustic parameters and the nonlinearity of the medium. The spectral analysis of the radio-frequency (RF) backscattered signals may yield important clinical information in the field of tissue characterization, as well as enhancing the detectability of tissue parenchymal diseases. Here, the authors propose a new tissue spectral imaging technique based on the wavelet packets (WP) decomposition. In a conventional ultrasound imaging system, the received echo-signals are generally decimated to generate a medical image, with a loss of information. With the proposed approach, all the RF data are processed to generate a set of frequency subband images. The ultrasound echo signals are simultaneously frequency decomposed and decimated, by using two quadrature mirror filters, followed by a dyadic subsampling. In addition, to enhance the lesion detectability and the image quality, the authors apply a nonlinear filter to reduce noise in each subband image. The proposed method requires simple additional signal processing and it can be implemented on any real-time imaging system. The frequency subband images, which are available simultaneously, can be either used in a multispectral display or summed up together to reduce speckle noise. To localize the different frequency response in the tissues, the authors propose a multifrequency display method where 3 different subband images, chosen among those available, are encoded as red, green, and blue intensities (RGB) to create a false-colored RGB image. According to the clinical application, different choices can evidence different spectral proprieties in the biological tissue under investigation. To enhance the lesion contrast in a grey-level image, one of the possible methods is the summation of the images obtained from narrow frequency subbands, according to the frequency compounding technique. The authors show that by adding the denoised subband images created with the WP decomposition, the contrast-to-noise ratio in 2 phantom images is largely increased.

Background Bone and joint scan using 99mTc-MDP is often used in rheumatologic practice, but there is little data on its effective relevance in evaluating chronic articular inflammatory diseases. Objectives The aim of this work has been to compare bone scan results against clinical evidence of joint inflammatory involvement, evaluating with both approaches the number of affected joints (NAJ) in a group of patients with rheumatoid arthritis (RA) or osteoarthritis (OA). Methods Bone scan was carried out in 75 consecutive patients (44 RA, 31 OA). The nuclear medicine specialist indicated in the report the list of joints showing uptake. In the same patients (without knowing the results of scintigraphy) a rheumatologist diagnosed the NAJ on the basis of clinical signs of inflammation. Then the patients were stratified in 2 * 2 tables according to the prevalence of clinical evidence or scintigraphic uptake. Results The distribution was found to be not significant (chi-square = 1.6, p = 0.2). The percentage of patients without uptake was only 5.3%. In 33 patients (44%) no clinical evidence was observed. Among these, 30 showed articular uptake (in an average of 7.0 * 4.6 joints). Considering only the patients with clinical evidence, the subjects with articular uptake were 41 out of 42 (97.6%) with an average of 8.6 * 4.6 involved joints. In these patients the ratio between number of joints with uptake and number of joints with clinical evidence (ratio uptake/clinical) was then calculated for each subject. Such a ratio resulted in an average of 2.9 * 3.6. These results were also confirmed analysing the data by sex, disease (RA or OA) and class of therapy. We then decided to assess if the greater prevalence of involved joints obtained with bone scan was correlated with an increase of inflammatory indexes. Taking into consideration the patients with clinical evidence, we performed multiple regression analysis using as dependent variable in distinct models the ratio uptake/clinical, the number of joints with clinical evidence and the number of joints showing uptake. The inflammatory indexes (ESR and CRP) were used as independent variables and age, sex, diagnosis and therapy were used as covariates. The uptake/clinical ratio did not show any significant correlation. The number of joints with clinical evidence correlates with ESR, those ones showing uptake correlates only with age, both with direct correlation. Conclusion The data obtained indicates that the articular scintigraphic uptake in AR and OA, on average, highlights a significantly higher number of joints involved as compared to the clinical test. It still remains to be defined if this is an overestimation related to the characteristics of the scan or if it is the sign of a higher sensibility in highlighting the inflammation location. An element of caution against the second hypothesis is established by the absence of correlation with the inflammatory indexes.

Molecular modeling analysis of compounds belonging to the recently published series of dihydro-alkoxy-benzyl-oxopyrimidines (DABOs), such as S-DABOs and DATNOs, gave support to the design of new 2, 6-disubstituted benzyl-DABO derivatives as highly potent and specific inhibitors of the HIV-1 reverse transcriptase (RT). To follow up on the novel DABO derivatives, we decided to investigate the effect of electron-withdrawing substituents in the benzyl unit of the S-DABO skeleton versus their anti-HIV-1 activity. Such chemical modifications impacted the inhibitory activity, especially when two halogen units were introduced at positions 2 and 6 in the phenyl portion of the benzyl group bound to C-6 of the pyrimidine ring. Various 5-alkyl-2-(alkyl(or cycloalkyl)thio)-6-(2, 6-dichloro(or 2,6-difluoro)phenylmethyl)-3, 4-dihydropyrimidin-4(3H)-ones were then synthesized and tested as anti-HIV-1 agents in both cell-based and enzyme (recombinant reverse transcriptase, rRT) assays. Among the various mono- and disubstituted phenyl derivatives, the most potent were those containing a 6-(2,6-difluorophenylmethyl) substituent (F-DABOs), which showed EC50's ranging between 40 and 90 nM and selectivity indexes up to >/=5000. An excellent correlation was found between EC50 and IC50 values which confirmed that these compounds act as inhibitors of the HIV-1 RT. The structure-activity relationships of the newly synthesized pyrimidinones are presented herein.

Double-phase 99mTc-methoxyisobutylisonitrile (MIBI) parathyroid scintigraphy has been proposed to detect hyperplastic parathyroid tissue, but the clinical usefulness of this technique in secondary hyperparathyroidism is still debated.Technetium-99m-MIBI parathyroid scintigraphy associated with parathyroid echography and [99mTc]pertechnetate thyroid scans were performed on 38 patients with chronic renal failure (CRF) and secondary hyperparathyroidism. In all patients, serum calcium, phosphorus, FT3, FT4, TSH, calcitonin and intact PTH (iPTH) were determined. Nine patients eventually underwent neck exploration and 28 parathyroid glands were removed.Thyroid diseases were excluded in all patients. Echography revealed parathyroid enlargement in 22/38 (58%) patients, while MIBI scintigraphy was positive in 28/38 (74%), including 5 ectopic glands. Mean serum iPTH concentration was significantly higher in MIBI-positive glands compared to MIBI-negative glands, but several discrepancies were observed in single patients. A significant positive correlation between serum iPTH and gland size was observed when MIBI-positive, but not MIBI-negative, parathyroids were considered. A paradoxical positive correlation between serum calcium and iPTH concentrations was found in MIBI-positive patients.Double-phase 99mTc-MIBI scintigraphy is positive in the majority of patients with uremic hyperparathyroidism. Comparison of scintigraphic data with morphological and functional data strongly suggests that 99mTc-MIBI scans do not reveal simple parathyroid enlargement but rather, identify the presence of hyperfunctioning (autonomous) parathyroid tissue suggestive of tertiary hyperparathyroidism.

As an approach to more extensive structural modifications of [(oxazolylphenoxy)alkyl]isoxazoles, we synthesized new compounds characterized by the replacement of the isoxazole nucleus with furan, pyrrole, and thiophene rings and by the presence of a ketocarbonyl group in the aliphatic chain connecting these pentatomic heterocycles to the 4-(4,5-dihydro-2-oxazolyl)phenoxy, 4-(ethoxycarbonyl)phenoxy, and 4-carboxyphenoxy moieties. Some pentamethylene derivatives were also prepared, and their antirhinovirus activity was compared to that of the corresponding ketomethylene derivatives. Syntheses were carried out by Friedel-Crafts acylation of the above pentatomic heterocycles and subsequent reaction of chloroalkyl ketones with the proper 4-substituted phenol. Reduction of the ketone function afforded the related polymethylene derivatives. The new compounds were tested for antirhinovirus activity and cytotoxicity in comparison with WIN 51711, used as reference drug. Inspection of the structure-activity relationships revealed that the thiophene ring and the carbonyl group are the structural components which to a large extent contribute to the positive biological profile in terms of both wideness of spectrum and low cytotoxicity. Among the various derivatives, compounds 8e,d showed in vitro the same potency of WIN 51711 but a cytotoxicity at least 10 times lower.

Earlier investigations on laboratory and pilot plant scale have shown the resort to microorganisms to be a practicable approach to the problem of purifying mineral dressing plant reject waters from residual flotation reagents and/or metal ions. In spite of the proven effectiveness of this method, one major drawback, namely the pathogenicity of some microorganisms, has so far hampered its application on a commercial scale. A research programme, aimed at developing a microbial reject water purification technique utilizing non-pathogenic strains was thus drawn up and is currently being implemented. Strains such as Bacillus subtilis, Saccharomyces cerevisiiae, Bifidobacterium bifidum, Lactobacillus acidophilus and Acinetobacter calcoaceticus , which are not harmful to human health, some of them being commonly found in the human intestine, have been successfully tested for removing alkylsulphates, alkylamines and fany acids from solutions simulating flotation plant tailings waters. Removals as high as 90% in less than 48 h can be easily achieved with no nutrient requirements, since in most cases the flotation reagent residue to be removed is metabolized by the microorganisms themselves.

The globin CACCC boxes are absolutely required for the appropriate regulation of the β-like globin genes. While the β-globin CACCC box binds EKLF/KLF1, a likely adult switching factor, analogous factors, interacting with the γ-globin gene and predicted to regulate the fetal stage of hemoglobin switching, have so far been elusive. By using yeast one hybrid assay, we have isolated four KLFs, KLF1, 2, 4, and 6, that bound the γ-CACCC bait. To establish their role in globin regulation and in the switching of hemoglobins, these factors were compared to four other KLFs already established or putative globin regulators, KLF3, 11, 13 and 16, mainly evaluating their ability to bind and transactivate the ε-, γ- and β-globin gene. γ-CACCC binding at variable intensities was confirmed in band shift assay for all four isolated KLFs, for KLF3 and, faintly, for KLF13. The ε- and β-CACCC were bound by the same factors with similar affinities with the exception of KLF3 and KLF13 that bound stronger to the β- and ε- than to the γ-CACCC box. On the other hand, KLF11 and 16 did not produce any specific complex in band shift assays with anyone of the globin CACCC boxes. More relevant differences were observed among the factors in the transactivation of single and dual luciferase reporters in both K562 and MEL cells. In these assays, most factors presented peculiar modulatory properties and specific promoter tropism. Several factors presented bidirectional activity displaying in the same time the capacity to stimulate and repress different globin promoters. KLF1 and 4 were the strongest stimulators of the β-globin promoter in both cell lines, whereas KLF2 activated the β-promoter only in K562 cells. KLF1 and especially KLF4 consistently repressed ε-globin expression especially in MEL cells. KLF3 behaved always as a general globin repressor in MEL cells, but acted as a weak stimulator of the γ- and ε-promoter in K562 cells. KLF4 was the strongest inhibitor of the ε-globin gene. KLF13 significantly stimulated the γ-promoter in both cell lines, whereas KLF3, 4 and 6 showed statistically significant stimulation only in MEL cells. By RT-PCR analysis we found that KLFs were highly variable in their tissue expression and that KLF1, 3 and 13 had the highest expression in erythroid tissues. Thus the level of tissue expression should ultimately determine which factors are really active in physiological conditions. Taken together our binding and expression studies suggest that several KLFs have the potential to modulate the activity of the globin genes and that the resulting globin expression will depend on the vectorial sum of the relative activities of the factors expressed at any given time of development. Furthermore, as some KLFs, like KLF1 and 4, exert opposite effects on fetal and adult globin genes, their role in hemoglobin switching may be direct and not only dependent on their ability to mediate promoter competition for the LCR.

Helicobacter pylori since Marshall and Warren's discovery has been an object of interest of gastroenterologists and many researchers of other specialties. What needs to be highlighted is also the growing interest of dentists in the role of oral residue of H. pylori in oral pathologies such as burning mouth syndrome, periodontitis and gingivitis. With the development of medical techniques more studies using highly specific diagnostic methods are performed in order to determine the transmission pattern of bacterial infection. Suggested faecal-oral and oral-oral routes of bacterial transmission raised interest in molecular biology methods as tools for the study of these environments. Additionally, co-existence of helical and coccoidal forms of H. pylori in the mentioned niches raised the question whether the latter is potentially pathogenic. This is why molecular biology is now giving a great opportunity to explore parts of the human body that could not have been diagnosed before using only gold standard diagnostic methods. Molecular techniques have shown their usefulness in examining the potential virulence of coccoid forms of bacterium. This review was created also to summarize the knowledge about molecular methods, especially different PCR techniques, as diagnostic tools that can help medical teams during regular diagnosis of gastritis.

With the aim of developing novel inhibitors of human immunodeficiency virus, various derivatives (10-17) related to 5H-pyrrolo[1,2-b] [1,2,5]benzothiadiazepine (PBTD) were prepared and tested in vitro. The title tricyclic derivatives were obtained by intramolecular cyclization of the open-chain intermediate arylpyrrylsulfones, followed by N-alkylation at position 10. Among test derivatives some 10-alkyl-5H-pyrrolo[1,2-b] [1,2,5]benzothiadiazepin-11(10H)-one-5,5-dioxides were found to exert potent and specific activity against HIV-1. In particular, 7-chloro derivatives 11i and j showed a potency comparable to that of nevirapine. However, when the chloro atom was shifted to the 8 position, the related products were scarcely active or totally inactive. Replacement of the pyrrole with pyrrolidine led to inactive products and the reduction of SO2 to S strongly diminished the antiviral potency. PBTD derivatives active in cell cultures were also inhibitory to the recombinant HIV-1 RT in enzyme assays, thus allowing the conclusion that PBTDs are a new class of non-nucleoside reverse transcriptase inhibitors (NNRTIs).