[Swiss clinical practice guidelines for skin cancer in organ transplant recipients]

Swiss clinical practice guidelines for skin cancer in organ transplant recipients Transplant patients have increased over the last decades. As a consequence of long-term immunosuppression, skin cancer, in particular squamous cell carcinoma (SCC), has become an important problem. Screening and education of potential organ transplant recipients (OTRs) regarding prevention of sun damage and early recognition of skin cancer are important before transplantation. Once transplanted, OTRs should be seen yearly by a dermatologist to ensure compliance with sun avoidance as well as for treatment of precancerosis and SCC. Early removal is the best treatment for SCC. Reduction of immunosuppression, switch to mTOR inhibitors and chemoprevention with acitretin may reduce the incidence of SCC. The dermatological follow-up of OTRs should be integrated into a comprehensive post-transplant management strategy.

Defective cerebral gamma-aminobutyric acid-A receptor density in patients with systemic lupus erythematosus and central nervous system involvement. An observational study

Gamma-aminobutyric acid-A (GABA-A) receptors play a crucial role in regulating neuronal excitability and cognitive functions. Single-photon emission computerized tomography (SPECT) analysis of GABA-A receptors binding by 123I-labelled Iomazenil (123I-IMZ) has been applied in some neuropsychiatric disorders to investigate conditions where GABA-A receptor density can be detected in several pathophysiological conditions. In this study we investigate cerebral GABA-A receptor density in a small series of patients with systemic lupus erythematosus (SLE) and cognitive impairment characterized by recurrent, episodic memory loss. Nine female patients with SLE and cognitive alterations underwent to a clinical neuropsychiatric evaluation including digital video-EEG, brain MRI, 99mTc-ECD brain SPECT and 123I-IMZ brain SPECT. All patients tested showed diffuse or focal GABA-A receptor density reduction. This is, to our knowledge, the first report on GABA-A receptor density abnormalities associated with cognitive defects in SLE patients. We hypothesize that in our series a decrease in GABA-A receptor density might be related to the neurological manifestations. Further studies are needed to clarify this aspect and the possible mechanisms. GABA-A receptor density impairment might be due to the SLE-related cerebral vasculopathy, or to neuronal-reacting auto-antibodies or drugs which could interfere with GABA-A receptors expression/binding. This study may support the concept that cognitive impairment in systemic lupus erythematosus could be the outcome of fine-tuned neurotransmission alterations.

Monitoring prion protein expression in complex biological samples by SERS for diagnostic applications

Surface-enhanced Raman spectroscopy (SERS) allows a new insight into the analysis of cell physiology. In this work, the difficulty of producing suitable substrates that, besides permitting the amplification of the Raman signal, do not interact with the biological material causing alteration, has been overcome by a combined method of hydrothermal green synthesis and thermal annealing. The SERS analysis of the cell membrane has been performed with special attention to the cellular prion protein PrP(C). In addition, SERS has also been used to reveal the prion protein-Cu(II) interaction in four different cell models (B104, SH-SY5Y, GN11, HeLa), expressing PrP(C) at different levels. A significant implication of the current work consists of the intriguing possibility of revealing and quantifying prion protein expression in complex biological samples by a cheap SERS-based method, replacing the expensive and time-consuming immuno-assay systems commonly employed.

Effect of low doses of atorvastatin on the urinary peptide profile of kidney transplant patients

Statins are prescribed to reduce posttransplant dyslipidemia, which is frequent among kidney graft recipients. Their efficacy to reduce cholesterol levels has been accompanied by pleiotropic effects. Proteomics is the study of the expressed complement of proteins in tissues or biological fluids. It includes the identification of changes in proteins that occur in various states, eg, after drug administration. Our study objectives were: (1) to analyze the effect of atorvastatin (10 mg/d) on lipid profile, renal function, proteinuria, and inflammation parameters, such as C-reactive protein (CRP), and (2) to use proteomics to ascertain whether this treatment modified the patients' urinary peptide profiles seeking to understand the molecular actions of the drug. Urinary peptide profiles, lipids, renal function parameters (creatinine clearance), proteinuria, and CRP were determined in 39 patients at baseline and at 12 weeks after atorvastatin treatment (10 mg/d). The peptide fraction of each sample acquired using magnetic beads was analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Our results showed that treatment with atorvastatin produced a significant reduction in lipid profile, but did not modify renal function (creatinine clearance), proteinuria, or CRP. The proteomic study showed that statin treatment did not produce significant changes in the urinary peptidome, although there was a tendency for some peptides to increase or decrease after the treatment.

Do retinal haemorrhages occur in infants with convulsions?

AIM

To determine the prevalence of retinal haemorrhages in infants presenting with convulsions and admitted to hospital, and to consider whether this finding indicates shaken baby syndrome.

METHODS

Prospective study of children aged 15 days to 2 years admitted with a diagnosis of first convulsion over a 2-year period (May 2004-May 2006). All infants were examined by an experienced ophthalmologist using indirect ophthalmoscopy within 72 h of admission.

RESULTS

182 of 389 children seen in the accident and emergency department were admitted and two were found to have retinal haemorrhages. Both children were eventually diagnosed as being abused.

CONCLUSIONS

Convulsions alone are unlikely to cause retinal haemorrhages in children under 2 years of age.

Using fast eye movements to study fatigue in multiple sclerosis

OBJECTIVE

To investigate whether internuclear ophthalmoparesis (INO) due to demyelination of the medial longitudinal fasciculus (MLF) provides a model for studying the poorly understood symptom of fatigue in multiple sclerosis (MS). We asked whether repetitive horizontal saccades increased eye movement disconjugacy in patients with MS with INO, but not in healthy subjects.

METHODS

We compared conjugacy of horizontal saccades in 9 patients with INO (4 bilateral, total 13) and 8 controls during minute 1 and minute 10 of a fatigue test; we measured the ratio of abducting/adducting peak velocity (versional disconjugacy index [VDI]).

RESULTS

VDI values were greater in patients than controls. During the fatigue test, controls showed no changes of VDI, but patients did (p < 0.005) for 10/13 INOs, with increased ratios in 5 cases and a decrease in the other 5.

CONCLUSION

Fatigue-induced worsening of conjugacy was observed in milder internuclear ophthalmoparesis (INO), and may reflect deteriorated fidelity of saccadic pulse transmission along demyelinated medial longitudinal fasciculus. Improved conjugacy was observed in the more severe INOs, and may be due to adaptive mechanisms, such as recruitment of vergence to aid gaze shifts. INO may provide an accessible, reductionist model to study how decreased neural transmission influences fatigue in multiple sclerosis, how the brain adapts to it, and whether drugs may prove therapeutic.

Effects of chronic copper exposure on fluvial systems: linking structural and physiological changes of fluvial biofilms with the in-stream copper retention

Long-term metal exposure is known to be responsible for a large variety of structural and functional changes in periphyton communities which allow these communities to adapt to metal-polluted conditions. This study aimed to link the changes that chronic copper (Cu) exposure causes on the structure and physiology of fluvial biofilms with the efficiency of the river systems in retaining phosphate and Cu. The effects of a chronic Cu exposure on the structure, physiology and induction of Cu tolerance of the community were evaluated by comparing this community with a non-exposed one. Results showed that periphyton chronically exposed to Cu had lower algal biomass, higher proportion of green algae, lower proportion of brown algae, and higher EPS content per unit of biomass than the un-exposed community. In addition, the chronically-exposed community showed a Cu content (both total and intracellular Cu content) ten times higher than the un-exposed community. While in-stream phosphate retention was not markedly influenced by chronic Cu exposure; Cu retention was clearly reduced, as was shown by a reduction in Cu retention efficiency (Cu-S(w)) and demand (Cu-Vf). The chronically-exposed periphyton, in spite of having high intracellular Cu concentration, showed similar photosynthetic efficiency than the un-exposed community and showed a higher Cu tolerance. It indicated that this community was acclimatized to Cu exposure and that this acclimatization was probably linked to the ability to detoxify and immobilize metals. These observations suggest that the fate of Cu in fluvial ecosystems will be influenced by the exposure history of the system. The results from this study indicate that metals will travel longer distances in metal-polluted streams compared to pristine systems having effects on water quality farther downstream.

Swiss clinical practice guidelines for skin cancer in organ transplant recipients

Patients with a solid organ transplant have increased in numbers and in individual survival in Switzerland over the last decades. As a consequence of long-term immunosuppression, skin cancer in solid organ recipients (SOTRs) has been recognized as an important problem. Screening and education of potential SOTRs about prevention of sun damage and early recognition of skin cancer are important before transplantation. Once transplanted, SOTRs should be seen by a dermatologist yearly for repeat education as well as early diagnosis, prevention and treatment of skin cancer. Squamous cell carcinoma of the skin (SCC) is the most frequent cancer in the setting of long-term immunosuppression. Sun protection by behaviour, clothing and daily sun screen application is the most effective prevention. Cumulative sun damage results in field cancerisation with numerous in-situ SCC such as actinic keratosis and Bowen's disease which should be treated proactively. Invasive SCC is cured by complete surgical excision. Early removal is the best precaution against potential metastases of SCC. Reduction of immunosuppression and switch to mTOR inhibitors and potentially, mycophenolate, may reduce the incidence of further SCC. Chemoprevention with the retinoid acitretin reduces the recurrence rate of SCC. The dermatological follow-up of SOTRs should be integrated into the comprehensive post-transplant care.

Measuring in-stream retention of copper by means of constant-rate additions

Human practices entail inputs of nutrients and toxicants such as heavy metals to the fluvial ecosystems. While nutrient dynamics in fluvial ecosystems have been widely studied for over three decades, dynamics of toxicants still remain unclear. In this investigation, the nutrient spiraling concept and associated methodologies to quantify nutrient retention in streams were applied to study copper (Cu) dynamics in streams. The present study aimed to quantify total dissolved Cu retention using a simplified system of indoor channels colonized with fluvial biofilms. Cu retention was studied at sub-toxic concentrations to avoid negative/lethal effects on biota. In addition, Cu retention was compared with retention estimates of a macronutrient, phosphate (PO(4)(3-)), which has been widely studied within the context of the nutrient spiraling concept. The methodology used allowed a successful quantification of Cu and PO(4)(3-) retention. The results showed higher retention efficiency for PO(4)(3-) than for Cu. The biofilm played a key role in retaining both solutes. Although retention efficiency for both solutes was higher in the experiments with colonized substrata compared to uncolonized substrata, we found a positive relationship between uptake rate and chlorophyll-a only for PO(4)(3-). Finally, retention efficiency for both solutes was influenced by water discharge, showing lower retention efficiencies under higher flow conditions. These results suggest that the fate and toxic effects of copper on stream biota may be strongly influenced by the prevailing environmental conditions. Our results indicate that the experimental approach considered can provide new insights into the investigation of retention of toxic compounds in fluvial systems and their controlling mechanisms.

Non-functionalized silver nanoparticles for a localized surface plasmon resonance-based glucose sensor

The optical properties of non-functionalized silver nanoparticles in ethanol solution have been analyzed and a progressive shift of localized surface plasmon resonances caused by the adding of increasing quantities of glucose has been observed. To understand this occurrence, the interaction of glucose molecules with the silver nanoparticle surface has been investigated using Raman spectroscopy. In addition, high resolution transmission electron microscopy shows the presence of superstructures on the silver nanoparticle surface that can be imputed to the presence of glucose.

[Prevention and therapy of critical ischemia in hemodialyzed patients]

The cardiovascular disease is largely increased in chronic renal failure and the patients have a 10-20 times higher mortality respect normal population. Besides habitual risk-factors they add the mineral metabolism alterations, iperomocisteine and chronical vessel flogosis. In these patients the vascular disease is often lately diagnosed, but early diagnosis would be extremely important to establish appropriate pharmacologic or surgical treatment (PTA or by pass). The basic diagnostic methods are still digital angiography, angio-NMR or angio-CT. In our experience appears that dialysed patients present high total mortality and re-vascolarization (particularly for peripheral occlusive disease) gives less guarantee of success. During last years endovascular surgery procedures extremely improved short-term prognosis for these patients. When there is no space for the re-vascolarization and the situation is strongly compromised by the presence of extended gangrene or infected lesion, amputation is still indicated and can be considered the only possible solution.