[What is new in 2014 for the specialist in hospital internal medicine? The point of view of university hospital chief residents]. / L'année 2014 mise en perspective par les internistes hospitaliers.

The year 2014 was rich in significant advances in all areas of internal medicine. Many of them have an impact on our daily practice and on the way we manage one problem or another. From the use of the ultrasound for the diagnosis of pneumonia to the choice of the site of venous access and the type of line, and the increasing complexity of choosing an oral anticoagulant agent, this selection offers to the readers a brief overview of the major advances. The chief residents in the Service of internal medicine of the Lausanne University hospital are pleased to share their readings.

[What is new in 2012 for the specialist in hospital internal medicine?]. / L'année 2012 de la perspective de l'interniste hospitalier.

The knowledge in internal medicine is constantly and so rapidly evolving that practices have to be updated and adjusted to recent scientific rules, in order to improve quality and efficiency in the day to day activities. Residents in the Service of internal medicine of the Lausanne University present several relevant papers published in 2012, whose results are susceptible to change the daily hospital practices. From modest impacts to real revolution, a variety of subjects are discussed in the perspective of evidence based medicine.

Reduction in circulating markers of endothelial dysfunction in HIV-infected patients during antiretroviral therapy.

OBJECTIVES: Antiretroviral therapy (ART) in HIV-infected patients is associated with increased cardiovascular risk. Circulating markers of endothelial dysfunction may be used to study early atherogenesis. The aim of our study was to investigate changes in such markers during initiation of ART. METHODS: In 115 HIV-positive treatment-naïve patients, plasma lipids, E-selectin, soluble intercellular adhesion molecule 1 (sICAM-1), soluble vascular cell adhesion molecule 1 (sVCAM-1), tissue-type plasminogen activator inhibitor 1 (tPAI-1) and high-sensitivity C-reactive protein (hsCRP) were measured before and after 2 and 14 months of ART. A control group of 30 healthy subjects was included. Values are mean+/-standard error of the mean. RESULTS: Prior to treatment, HIV-infected patients had elevated levels of sICAM-1 (296+/-24 vs. 144+/-12 ng/mL), tPAI-1 (18 473+/-1399 vs. 5490+/-576 pg/mL) and hsCRP (28 060+/-5530 vs. 6665+/-2063 ng/mL) compared with controls (P<0.001). In contrast, sVCAM-1 and E-selectin did not differ between the groups. Initiation of ART resulted in significantly lower levels of E-selectin (15.1+/-0.8; P<0.01), sICAM-1 (248+/-12 ng/mL; P<0.05), sVCAM-1 (766+/-33 ng/mL; P<0.001) and hsCRP (14 708+/-2358 ng/mL; P<0.001) after 2 months, which remained reduced at 14 months. tPAI-1 was not influenced by initiation of ART. CONCLUSIONS: Markers of endothelial dysfunction were elevated in treatment-naïve HIV-infected patients and were related to HIV RNA viral load. Initiation of ART reduced the levels of the majority of these markers. The positive effect of ART initiation was dependent on the duration of HIV infection prior to treatment.

BOLD-MRI for the assessment of renal oxygenation in humans: acute effect of nephrotoxic xenobiotics.

Hypoxia of renal medulla is a key factor implicated in the development of drug-induced renal failure. Drugs are known to influence renal hemodynamics and, subsequently, affect renal tissue oxygenation. Changes in renal oxygenation can be assessed non-invasively in humans using blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI). This study was designed to test the acute effects of administration of specific drugs in healthy human kidney oxygenation using BOLD-MRI. Acute changes in renal tissue oxygenation induced by the non-steroidal anti-inflammatory drug indomethacin, the iodinated radio-contrast media (RCM) iopromidum, and the calcineurin inhibitors cyclosporine micro-emulsion (CsA-ME) and tracrolimus were studied in 30 healthy volunteers. A modified Multi Echo Data Image Combination sequence was used to acquire 12 T(2)(*)-weighted images. Four coronal slices were selected to cover both kidneys. The mean R(2)(*) (1/T(2)(*)) values determined in medulla and cortex showed no significant changes induced by indomethacin and tacrolimus administration. CsA-ME decreased medullary (P=0.008) and cortical (P=0.004) R(2)(*) values 2 h after ingestion. Iopromidum caused a significant increase in medullary R(2)(*) within the first 20 min after injection (P<0.001), whereas no relevant changes were observed in renal cortex. None of the measurements showed left-right kidney differences. Significant differences in renal medullary oxygenation were evidenced between female and male subjects (P=0.013). BOLD-MRI was efficient to show effects of specific drugs in healthy renal tissue. Cyclosporine increased renal medullary oxygenation 2 h after ingestion of a single dose, whereas indomethacin and tacrolimus showed no effect on renal oxygenation. Injection of iodinated RCM decreased renal medullary oxygenation.

Learning and memory in the mosquito Aedes aegypti shown by conditioning against oviposition deterrence.

Oviposition site choice by female mosquitoes, Aedes aegypti (L) (Diptera: Culicidae), was affected by rearing them in water treated with 0.016% of the repellent Mozaway trade mark containing citronella and neem. Given a choice between a bowl of repellent-treated and a bowl of untreated water, Ae. aegypti reared in untreated water strongly preferred to oviposit on the clean water (93-98%) instead of repellent-treated water. This demonstrates effective deterrence of oviposition by dilute Mozaway trade mark. Those reared in repellent-treated water were less deterred: 38-46% of their eggs were laid on the repellent-treated water and 54-62% on the clean water. Evidently the female mosquitoes reared in repellent-treated water were conditioned against oviposition site deterrence, as shown when choice tests were conducted 6 days post-emergence from the treated water. This demonstrates learning and memory in the mosquito Ae. aegypti, with implications for dengue vector surveillance and control.

Photodynamic therapy with mTHPC and polyethylene glycol-derived mTHPC: a comparative study on human tumour xenografts.

The photosensitizing properties of m-tetrahydroxyphenylchlorin (mTHPC) and polyethylene glycol-derivatized mTHPC (pegylated mTHPC) were compared in nude mice bearing human malignant mesothelioma, squamous cell carcinoma and adenocarcinoma xenografts. Laser light (20 J/cm2) at 652 nm was delivered to the tumour (surface irradiance) and to an equal-sized area of the hind leg of the animals after i.p. administration of 0.1 mg/kg body weight mTHPC and an equimolar dose of pegylated mTHPC, respectively. The extent of tumour necrosis and normal tissue injury was assessed by histology. Both mTHPC and pegylated mTHPC catalyse photosensitized necrosis in mesothelioma xenografts at drug-light intervals of 1-4 days. The onset of action of pegylated mTHPC seemed slower but significantly exceeds that of mTHPC by days 3 and 4 with the greatest difference being noted at day 4. Pegylated mTHPC also induced significantly larger photonecrosis than mTHPC in squamous cell xenografts but not in adenocarcinoma at day 4, where mTHPC showed greatest activity. The degree of necrosis induced by pegylated mTHPC was the same for all three xenografts. mTHPC led to necrosis of skin and underlying muscle at a drug-light interval of 1 day but minor histological changes only at drug-light intervals from 2-4 days. In contrast, pegylated mTHPC did not result in histologically detectable changes in normal tissues under the same treatment conditions at any drug-light interval assessed. In this study, pegylated mTHPC had advantages as a photosensitizer compared to mTHPC. Tissue concentrations of mTHPC and pegylated mTHPC were measured by high-performance liquid chromatography in non-irradiated animals 4 days after administration. There was no significant difference in tumour uptake between the two sensitizers in mesothelioma, adenocarcinoma and squamous cell carcinoma xenografts. Tissue concentration measurements were of limited use for predicting photosensitization in this model.

mTHPC Polymer Conjugates: The In Vivo Photodynamic Activity of Four Candidate Compounds.

The in vivo photodynamic activities of four poly(ethylene glycol) (PEG) conjugates of the photosensitiser 5,10,15,20-tetrakis-(m-hydroxyphenyl)chlorin (mTHPC, temoporfin, Foscan(®)) were compared with that of mTHPC over a range of drug-light intervals using acute tumour necrosis and skeletal muscles swelling in a mouse model in order to ascertain the influence of linking group stability and PEG chain length on the photodynamic activity. The four compounds examined contained either PEG 2000 or PEG 5000 attached by carbonate or triazine linkages at the phenol hydroxyl groups of the mTHPC.All compounds tested caused tumour necrosis at drug-light intervals of between one and four days. mTHPC produced tumour necrosis of over 5 mm at drug-light intervals of 1 and 2 days with limited muscle damage at early drug-light intervals. The relatively labile carbonate-linked conjugates gave tumour necrosis similar to mTHPC but produced severe muscle and systemic phototoxicity on irradiation at 4-24 h after injection. The more stable triazine-linked conjugates produced no significant muscle damage at any of the drug-light intervals tested, but gave only limited tumour necrosis under the conditions tested. PEG chain length had relatively little effect on the patterns of bioactivity.It is concluded that both classes of mTHPC PEG conjugates may be suitable for photodynamic therapy if the problems of stability and early photosensitivity in the case of the carbonates and reduced potency in the case of the triazines can be overcome through improved formulations and PDT treatment regimens.

Experimental assessment of photodynamic therapy with chlorins for malignant mesothelioma.

OBJECTIVE: Photodynamic therapy (PDT) with two chlorin sensitisers was assessed on nude mice bearing human mesothelioma xenografts, and on intrathoracic tissues of minipigs with the same drug-light conditions to optimise the antitumour activity of PDT while preventing photosensitising injury to normal tissues. METHODS: Laser light (20 J/cm2) at 652 nm was delivered to the xenografts 1-4 days after i.p. administration of 0.1 mg/kg m-tetrahydroxyphenyl-chlorin (mTHPC) or an equimolar dose of polyethylene glycol-derived mTHPC (pegylated mTHPC), respectively. The extent of tumour necrosis was assessed by histomorphometry. Intraoperative PDT was then performed to the thoracic cavity of minipigs through a sternotomy with the same drug-light conditions at drug-light intervals ranging from 12 h to 6 days after i.v. administration of mTHPC and pegylated mTHPC, respectively. RESULTS: Both, mTHPC and pegylated mTHPC, resulted in photosensitised necrosis of mesothelioma xenografts at drug-light intervals from 1 to 4 days but the extent of necrosis was significantly larger by use of pegylated mTHPC instead of mTHPC at a drug-light interval of 3 and 4 days. The optimal tumourcidal effect was achieved with pegylated mTHPC at a drug-light interval of 4 days. The photosensitising effect of mTHPC on intrathoracic tissues of minipigs revealed severe damage of virtually all tissues except nerves at short drug-light intervals. Tissue damage gradually became less at longer drug-light intervals and was absent at intervals of 3 days and longer. In contrast, pegylated mTHPC resulted in no obvious change to any structure at any drug-light interval assessed. CONCLUSIONS: PDT with pegylated mTHPC reveals the potential of selective tumour destruction in this experimental setting and deserves further evaluation for intraoperative application in patients with malignant mesothelioma.

Honeybee vision: analysis of orientation and colour in the lateral, dorsal and ventral fields of view

The ability of honeybees (Apis mellifera) to learn and recognise peripherally presented patterns was investigated by training bees in a Y-maze which presented patterns on the side walls, the ceiling or the floor. We found that pattern orientation is learnt and recognised in the lateral and frontal visual field, but not in the dorsal or ventral fields. Colour information, in contrast, is used in the lateral and frontal as well as the ventral visual field, but not in the dorsal field. If pattern orientation is different on opposite sides of the visual field during training, both patterns are learned, but each on its own is sufficient for the bees to recognise the learnt stimulus. However, unilaterally learnt pattern information, be it orientation or colour, cannot be accessed when the test pattern is viewed on the other side. That is, interocular transfer of such information does not occur.

[Liver biopsy in ambulatory patients. Diagnostic value in comparison to conventional and quantitative liver function tests]. / Die Leberbiopsie beim ambulanten Patienten. Diagnostische Wertigkeit im Vergleich zu konventionellen und quantitativen Leberfunktionsprüfungen.

In this retrospective analysis we investigated the diagnostic yield of 148 consecutive liver biopsies performed as an outpatient procedure. In 144 patients, adequate specimens for histologic analysis were obtained. In these patients, 226 diagnoses were entertained. Clinical diagnosis was confirmed in 49.3%, modified in 43.8% and altered in 6.9%. Liver biopsy was particularly helpful in patients where an alcoholic etiology was suspected, since this could be confirmed in only 59.4% while in the others different, often treatable, causes of chronic liver disease were found. Neither conventional nor quantitative liver tests (galactose elimination capacity, aminopyrine breath test) served to differentiate reliably between severe and mild lesions. We conclude that liver biopsy remains an important diagnostic tool in patients with chronic liver disease, and that it can be safely performed on an outpatient basis in appropriately selected patients.

[Research in epidemiology and causality: the example of the Basel Multiple Sclerosis Study 1980 to 1986]. / Epidemiologie und Ursachenforschung: Das Beispiel der Basler Multiple-Sklerose-Studie 1980 bis 1986.

Statistic evaluations on multiple sclerosis 1980 to 1986 in two Swiss cantons have been analyzed, using stochastic mathematical models in order to investigate significance of and possible reasons for variations in incidence. Fluctuation rates of up to 20% could hereby be demonstrated to be due to chance. This could be validated by computer simulations and comparisons with published data. The results show that such apparently large fluctuations in incidence rates should thus be attributed to possible causes with utmost care and prompt for more detailed rules for collection of data.

[Multiple sclerosis in northwestern Switzerland]. / Die Multiple Sklerose in der Nordwestschweiz.

From 1980 to 1987 an epidemiologic survey was conducted in northwestern Switzerland (population 523,000) with the aim of registering as many MS cases as possible. The prevalence for the entire region was 142 per 100,000, with a maximum of 164/100,000 in the city of Basle. Extrapolation suggests there are more than 8000 MS patients living in Switzerland. Other interesting results were: a sex-ratio of 2.2 females:1 male. The mean age at clinical onset was 31.6 years. The mean survival was 30.6 years. Prevalence has grown in recent decades, mainly due to longer survival and to changes in age structure. The incidence presumably remained unchanged.

[Osteomyelofibrosis syndrome 33 years after thorotrast angiography]. / Osteomyelofibrose-Syndrom 33 Jahre nach Thorotrast-Angiographie.

33 years after carotid arteriography with thorotrast a 69-year-old patient died from osteomyelofibrosis with severe hematopoietic hypoplasia and myeloid metaplasia detected in liver, lymph nodes, kidney and epicardium. Twenty years before death he underwent "prophylactic" splenectomy; histologically the spleen merely showed hypoplasia, fibrosis and deposits of thorotrast. It is assumed that the osteomyelofibrosis syndrome is a specific complication of thorotrast application which has only rarely been described in the past. This suggestion is supported by observations suggesting that osteomyelofibrosis syndrome may be induced by radiation and by the fact that thorotrast gives rise to foreign body reactions associated with subsequent severe fibrosis. The development of myeloid metaplasia is assumed to be secondary to chronic hematopoietic insufficiency.