Impact of transmitted HIV-1 drug resistance on the efficacy of first-line antiretroviral therapy with two nucleos(t)ide reverse transcriptase inhibitors plus an integrase inhibitor or a protease inhibitor.

Objectives: To examine the impact of transmitted drug resistance (TDR) on response to first-line regimens with integrase strand transfer inhibitors (INSTIs) or boosted protease inhibitors (bPIs). Methods: From an Italian observational database (ARCA) we selected HIV-1-infected drug-naive patients starting two NRTIs and either an INSTI or a bPI, with an available pre-ART resistance genotype. The endpoint was virological failure (VF; plasma HIV-1 RNA >200 copies/mL after week 24). WHO surveillance drug resistance mutations and the Stanford algorithm were used to classify patients into three resistance categories: no TDR (A), TDR but fully-active ART prescribed (B), TDR and at least low-level resistance to one or more prescribed drug (C). Results: We included 1365 patients with a median follow-up of 96 weeks (IQR 54-110): 1205 (88.3%) starting bPI and 160 (11.7%) INSTI. Prevalence of TDR was 6.1%, 12.5%, 2.6% and 0% for NRTI, NNRTI, bPI and INSTI, respectively. Cumulative Kaplan-Meier estimates for VF at 48 weeks were 11% (95% CI 10.1%-11.9%) for the bPI group and 7.7% (95% CI 5.4%-10%) for the INSTI group. In the INSTI group, cumulative estimates for VF at 48 weeks were 6% (95% CI 4%-8%) in resistance category A, 5% (95% CI 1%-10%) in B and 50% (95% CI 30%-70%) in C (P < 0.001). Resistance category C [versus A, adjusted hazard ratio (aHR) 12.6, 95% CI 3.2-49.8, P < 0.001] and nadir CD4 (+100 cells/mm3, aHR 0.6, 95% CI 0.4-0.9, P = 0.03) predicted VF. In the bPI group, VF rates were not influenced by baseline resistance. Conclusions: Our data support the need for NRTI resistance genotyping in patients starting an INSTI-based first-line ART.

Listeria meningoencephalitis and anti-GQ1b antibody syndrome.

We report the first case of Listeria monocytogenes meningoencephalitis associated with anti-GQ1b antibody syndrome in an immunocompetent adult. A prompt diagnosis, made thanks to the multidisciplinary contribution, allowed a combined therapeutic approach leading to final favourable outcome, despite several intercurrent complications.

The influence of different shavers on the skin quantified by non-invasive reflectance confocal microscopy.

BACKGROUND: The impact of personal care devices on skin is mainly assessed using subjective tools. However, new objective, accurate non-invasive in vivo imaging techniques have been developed. The aim of this study was to evaluate the ability of reflectance confocal microscopy (RCM) in quantifying morphological impact of shavers on skin. Furthermore, tape stripping (TS) as method to study morphological impact of shavers was evaluated. METHODS: In 12 healthy male subjects, for two consecutive days, a split-face test was performed in the neck; on one side a shaver was applied, while the other side was exposed to TS. The stratum corneum (SC) thickness was quantified using RCM and sensory observations were evaluated using questionnaires. RESULTS: Shavers with a different impact on skin, can be discriminated by RCM; shaver B removed more SC after application than the skin friendlier shaver A. Furthermore, the changes in SC thickness induced by TS corresponded well to that of the shavers. CONCLUSION: RCM is able to quantify the impact of different shavers on skin. Besides, TS appeared to be a suitable model mimicking the mechanical impact of shavers on skin. RCM in combination with the TS model appeared to be a suitable minimally invasive model to obtain morphological and cell biological data on skin-material interactions caused by different personal care devices.

Impact of hepatitis B vaccination in children born to HBsAg-positive mothers: a 20-year retrospective study.

BACKGROUND: Preventive measures remain the best approach to control the spread of hepatitis B virus (HBV) infection. PATIENTS AND METHODS: To evaluate the effectiveness of vaccination against HBV, we conducted a 20-year retrospective study on 100 subjects, born to hepatitis B surface antigen (HBsAg)-positive mothers, who had received postexposure prophylaxis at the Clinic of Infectious Diseases (Siena University, Italy) during 1984-2004. All patients were tested for the presence of HBsAg, anti-HBs and anti-HB core antigen (anti-HBc). RESULTS: Two subjects (2%) acquired the infection as shown by the presence of anti-HBc. Of the 98 patients who did not acquire the infection, 62 of these (63.3%) had an anti-HBs concentration considered protective (> or =10 mIU/ml). The percentage of protected subjects decreased in relation to time from vaccination with a significant reduction (p = 0.009) of anti-HBs geometric mean titre (GMT) after 5 years, which reached the level of 10 mIU/ml after about 15 years. No patients without protective concentration have acquired the infection as of today. Only 12% of the HBsAg-positive mothers were followed in specialized structures after pregnancy, reflecting the scarce knowledge of the problem in the general population. CONCLUSION: Our data, while confirming the effectiveness of anti hepatitis B vaccination, highlight the need for postvaccination follow-up, particularly in high-risk categories, to prolong protection, through booster doses if necessary. We show, moreover, the importance of maintaining active surveillance in the territory to improve follow-up to chronic carriers and to sensitize families.

Outpatient parenteral antibiotic therapy for bone and joint infections: an italian multicenter study.

In the early eighties, the advantages of outpatient parenteral antibiotic therapy (OPAT) (reduced costs, no hospitalization trauma in children, no immobilization syndrome in elderly, reduction in nosocomial infections by multiresistant organisms) were identified in the United States, and suitable therapeutic programs were established. Currently, more than 250,000 patients per year are treated according to an OPAT program. In order to understand the different ways of managing OPAT and its results, a National OPAT Registry was set up in 2003 in Italy. Analysis of data concerning osteomyelitis, septic arthritis, prosthetic joint infection and spondylodiskitis, allowed information to be acquired about 239 cases of bone and joint infections, with particular concern to demographics, therapeutic management, clinical response, and possible side effects. Combination therapy was the first-line choice in 66.9% of cases and frequently intravenous antibiotics were combined with oral ones. Teicoplanin (38%) and ceftriaxone (14.7%), whose pharmacokinetic/pharmacodynamic properties permit once-a-day administration, were the two top antibiotics chosen; fluoroquinolones (ciprofloxacin and levofloxacin) were the most frequently utilized oral drugs. Clinical success, as well as patients' and doctors' satisfaction with the OPAT regimen was high. Side-effects were mild and occurred in 11% of cases. These data confirm that the management of bone and joint infections in an outpatient setting is suitable, effective and safe.

Relapsing fever in a traveller from Senegal: determination of Borrelia species using molecular methods.

We describe a case of a febrile patient returning from Senegal in which haemoscopic and molecular investigation confirmed tick-borne relapsing fever (TBRF), suggesting Borrelia crocidurae as the causative agent. This case emphasises the need to include TBRF in the differential diagnosis of fever following a journey from endemic countries, including malarial areas.

[Retrospective study of tuberculosis in the Province of Siena]. / Studio retrospettivo sui ricoveri per tubercolosi nella Provincia di Siena.

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

The effect of timing of vincristine administration during a course of fractionated radiotherapy in a mouse carcinoma.

It has been previously shown that the uptake of 3H-vincristine by the NT carcinoma tumour in CBA mice can vary by a factor of 3 during a course of fractionated radiotherapy (2 Gy day-1, 5 day week-1, for 5 weeks). Here the effect of therapeutic doses of vincristine given at times of either maximum or minimum uptake has been investigated. The results show that whereas vincristine alone has a dose-related effect on this tumour, when given in combination with fractionated radiation it is only effective if administered during the first few fractions. It does not seem to matter whether it is given at times of maximum or minimum uptake. It is concluded that vincristine either exacerbates the radiation-induced vascular damage so that drug extravasation is reduced or that it causes a shift in the time of appearance of the peaks and troughs of uptake. The possibility that radiation-induced resistance to vincristine may have played a part in the results is also discussed.

Paclitaxel as a radiosensitiser: a proposed schedule of administration based on in vitro data and pharmacokinetic calculations.

Paclitaxel is efficacious against many human cancers. Because it blocks cells at the radiosensitive G2-M interface, paclitaxel has been investigated as a radiosensitiser. The results have been equivocal and somewhat contradictory. It is impossible to obtain proper pharmacokinetic calculations, aimed at obtaining maximum cytotoxicity and/or radiosensitisation, without knowing (i) how long the drug must be in contact with the cells, (ii) how long the effect lasts after the drug is removed from the cellular environment, (iii) whether the drug acts as a radiosensitiser even when, like cis-platinum, it is added after the radiation and (iv) what the minimum quantity of drug in the cellular environment is required for both chemotoxicity and radiosensitisation. The present work addresses the above questions. Two radioresistant cell lines of human origin were used, A375 melanoma and S549 lung carcinoma, in a clonogenic assay where only colonies with 50 or more cells were counted. For the irradiation, 6 MV X-rays were used. Any G2-M block was quantified by cell cycle kinetics analysis. From the results, a simulation of pharmacokinetics was conducted to calculate the schedule of administration of paclitaxel most likely to achieve and maintain significant chemotoxocity and radiosensitisation. The minimum concentration of paclitaxel for measurable cytotoxicity was 3 nM for both cell lines, but the drug was more toxic to the A549 cells. The minimum concentration for measurable radiosensitisation was 3 nM for A375 and approximately 0.1 nM for A549, but whereas above 3 nM the radiosensitivity increased in A375, it decreased above 1 nM for A549. A minimum of 18 h incubation with the drug was necessary for measurable effects and the radiosensitising effects were lost soon after its removal. There was no radiosensitisation if paclitaxel was added after the radiation, and, at the minimum effective concentrations, it caused only a minor and transient G2-M block. The pharmacokinetic calculations predict that 15 mg/m2 paclitaxel given as a 1 h infusion 5 days/week for 3 weeks during the radiotherapy should achieve both cytotoxicity and radiosensitisation. The mechanism of radiosensitisation by paclitaxel at the concentrations suggested by our results does not appear to be via a G2-M block and is probably concentration dependent. The results imply that low-dose, daily infusions of paclitaxel for as long as possible during a course of radiotherapy are more likely to result in radiosensitisation and prolonged cytotoxicity than high-dose infusions given once a week.

Radiation absorbed dose from technetium-99m DTPA.

The whole-body retention of intravenously administered [99mTc]DTPA was measured by urine analysis and whole-body counting in eight normal subjects. On average, the elimination of [99mTc]DTPA was faster in these subjects than in 11 patients under study for hypertension whose whole-body retention data were used in MIRD Dose Estimate Report No. 12. The average residence time for [99mTc]DTPA in total body, less bladder contents, was only 65% of the MIRD value. However, despite this difference, the dosimetry is similar in both cases largely owing to the influence of radioactivity in bladder contents. Approximately 2-3% of the administered radioactivity was retained in the body for a time that was long relative to the physical half-life of 99mTc, and probably reflects a small amount of protein binding of the DTPA preparation.

Protein binding studies of technetium-99m-labeled phosphine and isocyanide cationic complexes.

Most 99mTc/phosphine/isocyanide complexes synthesized to date show preferential uptake by the myocardium of many animal species but not in man. A new complex has been synthesized, [99mTc(DEPE)2(CNR)2], +(DEPIC), where R = t - butyl isocyanide, which in three animal species images the myocardium very well, but in humans it remains primarily in the blood pool. One reason for the difference in the behavior of these complexes in different species could be the characteristics of their binding to plasma proteins. The protein binding characteristics of DEPIC and two other well-known complexes have therefore been studied. Whereas the other complexes bind nonspecifically to many proteins both in animal and human plasma, DEPIC binds almost exclusively to prealbumin in humans but nonspecifically to other proteins in the rabbit. The binding sites in human plasma appear to be those normally occupied by thyroxine on the prealbumin tetramer and these can be blocked by sodium salicylate.

Effect of non-steroidal anti-inflammatory drugs on the human small intestine.

The suggestion that the intestinal mucosa may be abnormally permeable and thus a site of antigen absorption in rheumatoid arthritis was tested by a 51Cr EDTA intestinal permeability test. Twelve patients with rheumatoid arthritis untreated by non-steroidal anti-inflammatory drugs (NSAIDs) had normal test results, while 12 NSAID-treated patients had increased intestinal permeability. Ten volunteers ingested aspirin, ibuprofen and indomethacin 8 and 1 hours before the study. The increased intestinal permeability was proportional to drug potency to inhibit cyclo-oxygenase. Intestinal permeability also increased following an indomethacin suppository, which suggests that the effect is systemically mediated. 111Indium leucocyte scintigrams and faecal collection showed no evidence of intestinal inflammation in 9 patients untreated by NSAIDs. Twenty-nine of 53 NSAID-treated patients showed abnormal localisation of 111indium in the right iliac fossa at 20 hours, and 32 of 49 patients had increased faecal excretion of 111indium. A 99mTc-porphyrin scan suggested that the main site of NSAID-induced intestinal inflammation was the small bowel. NSAIDs are thus shown to disrupt intestinal integrity and long term treatment leads to inflammation of the small intestine.

Pulmonary clearance of radiotracers after positive end-expiratory pressure or acute lung injury.

In anesthetized rabbits we measured clearance from lung to blood of eight aerosolized technetium-99m-labeled compounds: diethylenetriaminepentaacetate (99mTc-DTPA); cytochrome c; myoglobin; a myoglobin polymer; albumin; and anionic, cationic, and neutral dextrans of equivalent molecular size. We investigated the effect of applying positive end-expiratory pressure (PEEP) and, on a subsequent occasion, of injecting oleic acid intravenously to produce acute lung injury on the pulmonary clearance rate. Base-line clearance rates were monoexponential and varied with the molecular weights of the radiotracers. For each tracer the rate of clearance was increased a similar degree by either PEEP or oleic acid. However, with PEEP, clearance remained monoexponential, whereas after oleic acid, smaller molecular-weight radiotracers had multiexponential clearance curves. This suggests that after oleic acid the alveolar epithelium breaks down in a nonuniform fashion. We conclude that differentiation of the effect of PEEP from that of severe lung injury caused by oleic acid is not readily accomplished by either increasing the size of the tracer molecule or by varying the molecular charge.

Clearance of charged and uncharged dextrans from normal and injured lungs.

To examine how molecular charge affects the transfer of molecules across the alveolar-capillary barrier, we prepared the following dextrans of equivalent molecular size (mol wt 10,000) but varying molecular charge: neutral dextran, cationic DEAE dextran, and anionic dextran sulfate. These were labeled with 99mTc. The lungs of three groups of anesthetized rabbits were insufflated with dextran aerosols, with six rabbits receiving each type, and the half-time pulmonary clearance (t1/2) was measured. Control t1/2's (95% confidence limits) were 95 (74-120), 227 (192-268), and 291 (246-345) min for neutral, cationic, and anionic dextrans, respectively. One week later, when the same animals were restudied 4 h after 3 micrograms/kg iv endotoxin, t1/2's were 102 (75-139), 167 (149-187), and 126 (102-154) min, respectively. After 30 min during this repeat study, animals were ventilated with 20 breaths of cigarette smoke, which acutely increased the clearance rate to 34 (26-46), 25 (20-31), and 13 (7-24) min, respectively. Mean carboxyhemoglobin levels were not significantly different in the three groups: 13.6, 12.7, and 11.1%, respectively. These results demonstrated that neutral dextrans showed the same clearance rate before and after endotoxin, whereas the charged dextrans had a significantly faster clearance after endotoxin. After smoke exposure the anionic dextran left the lung more rapidly than the neutral dextran. Thus molecular charge affects solute transfer across the alveolar-capillary barrier in both normal and injured lungs, and an effect of endotoxin on the lung can be detected with charged dextrans but not with neutral dextran.

Imaging of human thrombi in the rabbit jugular vein: I: Comparison of two fibrin-specific monoclonal antibodies.

The development of monoclonal antibodies with a specificity for cross-linked fibrin may have a potential role in the detection and of thrombi and thrombolytic therapy. In this study, two monoclonal antibodies with a specificity for fibrin have been examined. In vitro studies have shown NIBn 123 (which has a high affinity for X-oligomer) and DD-3B6 to bind to immobilised fibrin on PVC plates as well as plasma clots which were incubated in the presence of plasma. The Km values for NIBn 123 and DD-3B6 wre 1.0 x 10(10)/7.7 x 10(8) M and 2.6 x 10(8) M respectively. No significant binding to fibrinogen either immobilised or in solution was found. The binding of these antibodies to a human thrombus in the jugular vein of the rabbit was monitored over a 24 hour period. Preferential binding of each antibody reached a ratio of approximately 1.0 (jugular/heart) at 24 hours and an image was detected.

77Br-p-bromospiperone: a ligand for in vivo labelling of dopamine receptors.

A high striatum: cerebellum ratio of 77Br-p-bromospiperone (77Br-BrSp) was observed in rat brain following tail vein injection of the drug. Striatal 77Br-BrSp was stereospecifically displaced by the isomers of flupenthixol. After chronic haloperidol administration striatal dopamine receptor supersensitivity was demonstrated both by increased 3H-spiperone binding to striatal membranes in vitro and by increased striatal 77Br-BrSp content. These results confirm and extend previous findings and enhance interest in the use of 77Br-BrSp for the in vivo assessment of central dopamine receptors in man.

Synthetic porphyrins as tumour-localizing agents.

A series of radioactively labelled porphyrin analogues have been synthesized and compared for tissue distribution and tumour uptake against 67Ga in the same tumour-mouse system. The compounds were: 14C-ms-tetraphenylporphine sulphonate (14C-TPPS), 35S-ms-tetraphenylporphine sulphonate (TPP35S), 35S-ms-tetra[beta-naphthyl]porphine sulphonate (TNP35S), 14C-ms-thienylphenylporphine sulphonate (14C-TTPPS) and 35S-ms-tetra[p-tolyl]porphine sulphonate (TTP35S). 14C-TPPS and TNP35S appear to concentrate in tumours to a greater extent than 67Ga (ratios of tumour uptake for TPPS/67Ga and TNPS/67Ga were about two and three respectively) but their uptake in kidneys and lungs was also greater than that of gallium. The type of side group attached to the central tetrapyrrole ring appears to have a substantial effect on the tumour-localizing properties of these compounds. Comparison of 14C and 35S-labeled TPPS indicates that the sulphonate groups are split off in vivo and that compounds with highly aromatic side groups (e.g. TNPS) and a radioactive label in a non-labile part of the molecule (e.g. in the tetrapyrrole ring system itself) would show even better tumour localization. The feasibility of synthesizing porphyrins with a variety of reactive side groups suggests that it may be possible to introduce suitable gamma-emitters while retaining the tumour-localizing properties.