Dimethyl fumarate-induced lymphocyte count drop is related to clinical effectiveness in relapsing-remitting multiple sclerosis.

BACKGROUND AND PURPOSE: Dimethyl fumarate (DMF) causes a mean lymphocyte count drop of approximately 30% in relapsing-remitting multiple sclerosis (RRMS) patients. The relationship between this reduction and DMF effectiveness is controversial. The objective was to investigate if the decrease in absolute lymphocyte count (ALC) from baseline during DMF treatment is associated with clinical and magnetic resonance imaging (MRI) disease activity. A secondary aim was to evaluate ALC variations over time in a real-life cohort of DMF-treated patients. METHODS: Demographic, laboratory, clinical and MRI data were collected in this observational multicentre study, conducted on RRMS patients treated with DMF for at least 6 months. Multivariate Cox models were performed to evaluate the impact of 6-month ALC drop on time to no evidence of disease activity (NEDA-3) status loss. NEDA-3 is defined as absence of clinical relapses, MRI disease activity and confirmed disability progression. RESULTS: In all, 476 patients (312 females, age at DMF start 38.4 ± 9.97 years) were analysed up to 5-year follow-up. A greater lymphocyte decrease was associated with a lower risk of NEDA-3 status loss (hazard ratio 0.87, P = 0.01). A worse outcome in patients with lower ALC drop (<11.5%), compared with higher tertiles (11.5%-40.5% and >40.5%), was observed (P = 0.008). The nadir of ALC drop (-33.6%) and 35% of grade III lymphopaenia cases occurred after 12 months of treatment. CONCLUSION: A higher lymphocyte count drop at 6 months is related to better outcomes in DMF-treated patients. A careful ALC monitoring should be pursued up to 24 months of treatment.

Gemcitabine-based adjuvant chemotherapy in subtypes of ampullary adenocarcinoma: international propensity score-matched cohort study.

BACKGROUND: Whether patients who undergo resection of ampullary adenocarcinoma have a survival benefit from adjuvant chemotherapy is currently unknown. The aim of this study was to compare survival between patients with and without adjuvant chemotherapy after resection of ampullary adenocarcinoma in a propensity score-matched analysis. METHODS: An international multicentre cohort study was conducted, including patients who underwent pancreatoduodenectomy for ampullary adenocarcinoma between 2006 and 2017, in 13 centres in six countries. Propensity scores were used to match patients who received adjuvant chemotherapy with those who did not, in the entire cohort and in two subgroups (pancreatobiliary/mixed and intestinal subtypes). Survival was assessed using the Kaplan-Meier method and Cox regression analyses. RESULTS: Overall, 1163 patients underwent pancreatoduodenectomy for ampullary adenocarcinoma. After excluding 187 patients, median survival in the remaining 976 patients was 67 (95 per cent c.i. 56 to 78) months. A total of 520 patients (53·3 per cent) received adjuvant chemotherapy. In a propensity score-matched cohort (194 patients in each group), survival was better among patients who received adjuvant chemotherapy than in those who did not (median survival not reached versus 60 months respectively; P = 0·051). A survival benefit was seen in patients with the pancreatobiliary/mixed subtype; median survival was not reached in patients receiving adjuvant chemotherapy and 32 months in the group without chemotherapy (P = 0·020). Patients with the intestinal subtype did not show any survival benefit from adjuvant chemotherapy. CONCLUSION: Patients with resected ampullary adenocarcinoma may benefit from gemcitabine-based adjuvant chemotherapy, but this effect may be reserved for those with the pancreatobiliary and/or mixed subtype.

ANTECEDENTES: Actualmente se desconoce si la quimioterapia adyuvante ofrece un beneficio en la supervivencia de los pacientes que se someten a resección de un adenocarcinoma ampular. El objetivo de este estudio fue comparar la supervivencia mediante la concordancia estimada por emparejamiento por puntaje de propensión, entre pacientes con y sin quimioterapia adyuvante después de la resección de un adenocarcinoma ampular. MÉTODOS: Se realizó un estudio internacional de cohortes multicéntrico, que incluyó a los pacientes que se sometieron a una duodenopancreatectomía por adenocarcinoma ampular (2006-2017) en 13 centros de seis países. Los puntajes de propensión se usaron para emparejar a los pacientes que recibieron quimioterapia adyuvante con los que no; tanto en la cohorte completa como en dos subgrupos (subtipo pancreaticobiliar / mixto e intestinal). La supervivencia se evaluó utilizando el método de Kaplan-Meier y las regresiones de Cox. RESULTADOS: En total, 1.163 pacientes fueron sometidos a una duodenopancreatectomía por adenocarcinoma ampular. Después de excluir a 179 pacientes, la mediana de supervivencia de los 976 pacientes restantes fue de 67 meses (i.c. del 95%, 56-78), de los cuales un total de 520 pacientes (53%) recibieron quimioterapia adyuvante. En una cohorte de emparejamiento por puntaje de propensión (194 versus 194 pacientes), la mediana de supervivencia fue mejor en los pacientes tratados con quimioterapia adyuvante en comparación con aquellos sin quimioterapia adyuvante (no se alcanzó la mediana de supervivencia versus 60 meses, respectivamente; P = 0,051). En el subtipo pancreaticobiliar/mixto se observó un beneficio en la supervivencia; no se alcanzó la mediana de supervivencia en pacientes que recibieron quimioterapia adyuvante versus 32 meses en el grupo sin quimioterapia, P = 0,020. El subtipo intestinal no mostró beneficio en la supervivencia de la quimioterapia adyuvante. CONCLUSIÓN: Los pacientes con adenocarcinoma ampular resecado pueden beneficiarse de la quimioterapia adyuvante basada en gemcitabina, pero este efecto podría reservarse para aquellos pacientes con subtipo de tumor pancreaticobiliar y/o mixto.

Cerebrospinal fluid kappa and lambda free light chains in oligoclonal band-negative patients with suspected multiple sclerosis.

BACKGROUND AND PURPOSE: Cerebrospinal fluid (CSF) kappa free light chains (FLCs) may be a more sensitive marker of intrathecal immunoglobulin (Ig)G synthesis compared with oligoclonal bands (OCBs). Our aim was to retrospectively determine the additional value of the kappa and lambda index (CSF FLC/serum FLC)/(CSF albumin/serum albumin) in predicting a multiple sclerosis (MS) diagnosis in a group of OCB-negative patients with suspected MS. METHODS: The CSF and serum kappa and lambda FLCs were tested using the Freelite kit (serum) and Freelite Mx (CSF) assay (The Binding Site Group, Bimingham, UK) in 391 OCB-negative patients with suspected/possible MS and in 54 OCB-positive patients with MS. RESULTS: The CSF kappa FLC levels were below the detection limit (0.27 mg/L) in 61% of patients. Using quantitative data, we found the best kappa index cut-off value for the prediction of MS to be 5.8. A kappa index ≥5.8 was present in 25% of OCB-negative MS (23/92) and in 98% of OCB-positive patients with MS. Using a qualitative approach and a kappa index cut-off of 5.9, based on literature data, we likewise found that 24% of OCB-negative patients with MS had a kappa index ≥5.9, compared with 5.4% of OCB-negative patients without MS (P < 0.001). No reliable data could be obtained for the lambda index; lambda FLCs were below the detection limit (0.68 mg/L) in 90% of CSF samples. CONCLUSIONS: The kappa index could contribute to the identification of OCB-negative patients with a high probability of an MS diagnosis. Using more sensitive techniques might even improve the diagnostic performance of the kappa index and better define the role of the lambda index.

Informing MS patients on treatment options: a consensus on the process of consent taking.

In the last years, change in multiple sclerosis (MS) therapeutic scenario has highlighted the need for an improved doctor-patient communication in advance of treatment initiation in order to allow patient's empowerment in the decision-making process. AIMS: The aims of our project were to review the strategies used by Italian MS specialists to inform patients about treatment options and to design a multicentre shared document that homogenizes the information about disease-modifying treatment (DMTs) and the procedure of taking informed consent in clinical practice. RESULTS: The new resource, obtained by consensus among 31 neurologists from 27 MS Centres in Italy with the supervision of a medico-legal advisor, received the aegis of Italian Neurological Society (SIN) and constitutes a step toward a standardized decision process around DMTs in MS.

Anti-inflammatory disease-modifying treatment and disability progression in primary progressive multiple sclerosis: a cohort study.

BACKGROUND AND PURPOSE: Treatment options in primary progressive multiple sclerosis (PPMS) are scarce and, with the exception of ocrelizumab, anti-inflammatory agents have failed to show efficacy in ameliorating disability progression. The aim of this study was to investigate a potential effect of anti-inflammatory disease-modifying treatment on disability outcomes in PPMS. METHODS: Using MSBase, a large, international, observational database, we identified patients with PPMS who were either never treated or treated with a disease-modifying agent. Propensity score matching was used to select subpopulations with similar baseline characteristics. Expanded Disability Status Scale (EDSS) outcomes were compared with an intention-to-treat and an as-treated approach in paired, pairwise-censored analyses. RESULTS: Of the 1284 included patients, 533 were matched (treated, n = 195; untreated n = 338). Median on-study pairwise-censored follow-up was 3.4 years (quartiles 1.2-5.5). No difference in the hazard of experiencing 3-month confirmed EDSS progression events was observed between the groups [hazard ratio (HR), 1.0; 95% confidence interval (CI), 0.6-1.7, P = 0.87]. We did not find significant differences in the hazards of confirmed EDSS improvement (HR, 1.0; 95% CI, 0.6-1.6, P = 0.91) or reaching a confirmed EDSS step ≥7 (HR, 1.1; 95% CI, 0.7-1.6, P = 0.69). CONCLUSION: Our pooled analysis of disease-modifying agents suggests that these therapies have no substantial effect on short- to medium-term disability outcomes in PPMS.

HBV reactivation in patients with HCV/HBV cirrhosis on treatment with direct-acting antivirals.

Anecdotal reports suggest that patients with chronic hepatitis C virus (HCV) hepatitis and overt or occult hepatitis B virus (HBV) coinfection may reactivate HBV when HCV is suppressed or cleared by direct-acting antivirals (DAAs). We assessed the prevalence of overt or previous HBV coinfection and the risk of HBV reactivation in patients with HCV cirrhosis treated with DAAs. This was a retrospective cohort of 104 consecutive patients with HCV cirrhosis treated with DAAs. Serum HCV-RNA and HBV-DNA were tested at weeks 4, 8 and 12 of DAAs therapy and at week 12 of follow-up. At the start of DAAs, eight patients (7.7%) were HBsAg positive/HBeAg negative with undetectable HBV-DNA and low levels of quantitative HBsAg (four on nucleos(t)ide analogues [NUCs] and four inactive carriers), 37 patients (35.6%) had markers of previous HBV infection (25 anti-HBc positive, 12 anti-HBc/anti-HBs positive) and 59 (56.7%) had no evidence of HBV infection. Sixty-seven patients (64.4%) were HCV-RNA negative at week 4 and 98 (94.2%) achieved sustained virological response. All four HBsAg-positive patients treated with NUCs remained HBV-DNA negative, but three of four untreated patients showed an increase in HBV-DNA of 2-3 log without a biochemical flare and achieved HBV-DNA suppression when given NUCs. During or after DAAs, by conventional assay, HBV-DNA remained not detectable in all 37 anti-HBc-positive patients but in three of them (8.1%) HBV-DNA became detectable with a highly sensitive PCR. HBV reactivation is likely to occur in untreated HBV/HCV-coinfected cirrhotic patients when they undergo HCV treatment with DAAs. Pre-emptive therapy with NUCs should be considered in this setting. Anti-HBc-positive patients rarely reactivate HBV without clinical or virological outcomes.

Dynamics of Ferrofluid Drops on Magnetically Patterned Surfaces.

The motion of liquid drops on solid surfaces is attracting a lot of attention because of its fundamental implications and wide technological applications. In this article, we present a comprehensive experimental study of the interaction between gravity-driven ferrofluid drops on very slippery oil-impregnated surfaces and a patterned magnetic field. The drop speed can be accurately tuned by the magnetic interaction, and more interestingly, drops are found to undergo a stick-slip motion whose contrast and phase can be easily tuned by changing either the strength of the magnetic field or the ferrofluid concentration. This motion is the result of the periodic modulation of the external magnetic field and can be accurately analyzed because the intrinsic pinning due to chemical defects is negligible on oil-impregnated surfaces.

Active immunization status against measles, mumps, rubella, hepatitis B in internationally adopted children, surveyed at the university hospital of Palermo, Sicily.

INTRODUCTION: The internationally adopted child is a fragile subject who often shows an incomplete health documentation, which hinders the complete assessment of health status. MATERIALS AND METHODS: Between January 2010 and June 2016, at the University Hospital "AOUP P. Giaccone" of Palermo, we reviewed the health documentations of 111 children recently arrived in Italy following the conclusion of the international adoption procedure. 62.2% of the children were male, of various nationalities and with an average age of 7 years (± 3.4). This study aims to detect, in the observed sample, the reliability of the vaccinal documentation and the real acquired immunization. We intend to estimate the presence of IgG against Measles, Mumps, Rubella and Hepatitis B viruses. RESULTS: Percentages of subjects with a complete correspondence between documentation attesting the successful vaccination and the effective immunization were: 78% for measles, 66% for mumps, 84% for rubella, 71% for hepatitis B. Percentages of subjects without vaccinal documentation but with positive evidence of IgG were: 50% for measles, 38% for mumps, 71% for rubella, 50% for hepatitis B. CONCLUSIONS: The partial correspondence found between vaccinations performed and real immune status can be attributed to several reasons: poor reliability of the received health documentation, the complex economic situation of the health services in the countries of origin, the incorrect vaccines storage or the administration beyond the expiration date, the poor immunological response due to concomitant diseases or severe malnutrition, the probable non-administration of the expected booster dose. Particular attention needs to be paid to this population, which may represent a risk group susceptible to vaccine-preventable diseases.

Minimal Excitations in the Fractional Quantum Hall Regime.

We study the minimal excitations of fractional quantum Hall edges, extending the notion of levitons to interacting systems. Using both perturbative and exact calculations, we show that they arise in response to a Lorentzian potential with quantized flux. They carry an integer charge, thus involving several Laughlin quasiparticles, and leave a Poissonian signature in a Hanbury Brown-Twiss partition noise measurement at low transparency. This makes them readily accessible experimentally, ultimately offering the opportunity to study real-time transport of Abelian and non-Abelian excitations.

Amyotrophic lateral sclerosis: a comparison of two staging systems in a population-based study.

BACKGROUND AND PURPOSE: To compare two recently developed staging systems for amyotrophic lateral sclerosis (ALS) [King's College and Milano-Torino staging (MITOS) systems] in an incident, population-based cohort of patients with ALS. METHODS: Since 2009, a prospective registry has been recording all incident cases of ALS in the Emilia Romagna region in Italy. For each patient, detailed clinical information, including the ALS functional rating scale score, is collected at each follow-up. RESULTS: Our study on 545 incident cases confirmed that King's College stages occurred at predictable times and were quite evenly spaced out throughout the disease course (occurring at approximately 40%, 60% and 80% of the disease course), whereas MITOS stages were mostly skewed towards later phases of the disease. In the King's College system there was a decrease in survival and an increase in deaths with escalating stages, whereas in the MITOS system survival curves pertaining to intermediate stages overlapped and the number of deaths was fairly homogenous throughout most stages. CONCLUSIONS: The King's College staging system had a higher homogeneity (i.e. smaller differences in survival among patients in the same stage) and a higher discriminatory ability (i.e. greater differences in survival among patients in different stages), being more suitable for individualized prognosis and for measuring efficacy of therapeutic interventions.

Abdominal scar endometriosis: case report.

Abdominal scar endometriosis, corresponding to the presence of an endometrial tissue near or inside an abdominal surgical incision, is a rare clinical event that can occur in women after gynecological or obstetric surgery. Generally, a triad consisting of underlying mass at the incision, cyclic menstrual scar pain, and history of previous gynecological or obstetric surgery leads to the preoperative diagnosis. In rare cases, the clinical presentation is atypical and the differential diagnosis with incarcerated incisional hernia, granuloma, abscess or other soft tissue tumors can be difficult. The authors describe the case of 39-year-old woman who underwent three previous cesarean sections, with a 20-week history of underlying palpable mass at the Pfannenstiel incision, associated to continuous pain. In this case, a surgical excision followed by the histology definitely clarified the diagnosis.

Real-time decoherence of Landau and Levitov quasiparticles in quantum Hall edge channels.

Quantum Hall edge channels at integer filling factor provide a unique test bench to understand the decoherence and relaxation of single-electron excitations in a ballistic quantum conductor. In this Letter, we obtain a full visualization of the decoherence scenario of energy (Landau)- and time (Levitov)-resolved single-electron excitations at filling factor ν = 2. We show that the Landau excitation exhibits a fast relaxation followed by spin-charge separation whereas the Levitov excitation only experiences spin-charge separation. We finally suggest to use Hong-Ou-Mandel-type experiments to probe specific signatures of these different scenarios.

Tuning drop motion by chemical patterning of surfaces.

We report the results of extensive experimental studies of the sliding of water drops on chemically heterogeneous surfaces formed by square and triangular hydrophobic domains printed on glass surfaces and arranged in various symmetric patterns. Overall, the critical Bond number, that is, the critical dimensionless force needed to depin the drop, is found to be strongly affected by the shape and the spatial arrangement of the domains. Soon after the droplet begins to move, stick-slip motion is observed on all surfaces, although it is less pronounced than that on striped surfaces. On the triangular patterns, anisotropic behavior is found with drops sliding down faster when the tips of the glass hydrophilic triangles are pointing in the down-plane direction. Away from the critical Bond number, the dynamic regime depends mainly on the static contact angle and weakly on the actual surface pattern. Lattice Boltzmann numerical simulations are performed to validate the experimental results and test the importance of the viscous ratio between the droplet phase and the outer phase.

Chronic telogen effluvium and female pattern hair loss are separate and distinct forms of alopecia: a histomorphometric and immunohistochemical analysis.

BACKGROUND: Chronic telogen effluvium (CTE), a poorly understood condition, can be confused with or may be a prodrome to female pattern hair loss (FPHL). The pathogenesis of both is related to follicle cycle shortening and possibly to blood supply changes. AIM: To analyze a number of histomorphometric and immunohistochemical findings through vascular endothelial growth factor (VEGF), Ki-67, and CD31 immunostaining in scalp biopsies of 20 patients with CTE, 17 patients with mild FPHL and 9 controls. METHODS: Ki-67 index and VEGF optical density were analyzed at the follicular outer sheath using ImageJ software. CD31 microvessel density was assessed by a Chalkley grid. RESULTS: Significant follicle miniaturization and higher density of nonanagen follicles were found in FPHL, compared with patients with CTE and controls. Ki-67+ index correlated positively with FPHL histological features. The FPHL group showed the highest VEGF optical density, followed by the CTE and control groups. No differences were found in CD31 microvessel density between the three groups. CONCLUSIONS: Histomorphometric results establish CTE as a distinct disorder, separate from FPHL from its outset. Its pathogenic mechanisms are also distinct. These findings support the proposed mechanism of 'immediate telogen release' for CTE, leading to cycle synchronization. For FPHL, accelerated anagen follicular mitotic rates and, thus, higher Ki-67 and VEGF values, would leave less time for differentiation, resulting in hair miniaturization.

Comparative effectiveness and cost-effectiveness of natalizumab and fingolimod in rapidly evolving severe relapsing-remitting multiple sclerosis in the United Kingdom.

AIM: To evaluate the real-world comparative effectiveness and the cost-effectiveness, from a UK National Health Service perspective, of natalizumab versus fingolimod in patients with rapidly evolving severe relapsing-remitting multiple sclerosis (RES-RRMS). METHODS: Real-world data from the MSBase Registry were obtained for patients with RES-RRMS who were previously either naive to disease-modifying therapies or had been treated with interferon-based therapies, glatiramer acetate, dimethyl fumarate, or teriflunomide (collectively known as BRACETD). Matched cohorts were selected by 3-way multinomial propensity score matching, and the annualized relapse rate (ARR) and 6-month-confirmed disability worsening (CDW6M) and improvement (CDI6M) were compared between treatment groups. Comparative effectiveness results were used in a cost-effectiveness model comparing natalizumab and fingolimod, using an established Markov structure over a lifetime horizon with health states based on the Expanded Disability Status Scale. Additional model data sources included the UK MS Survey 2015, published literature, and publicly available sources. RESULTS: In the comparative effectiveness analysis, we found a significantly lower ARR for patients starting natalizumab compared with fingolimod (rate ratio [RR] = 0.65; 95% confidence interval [CI], 0.57-0.73) or BRACETD (RR = 0.46; 95% CI, 0.42-0.53). Similarly, CDI6M was higher for patients starting natalizumab compared with fingolimod (hazard ratio [HR] = 1.25; 95% CI, 1.01-1.55) and BRACETD (HR = 1.46; 95% CI, 1.16-1.85). In patients starting fingolimod, we found a lower ARR (RR = 0.72; 95% CI, 0.65-0.80) compared with starting BRACETD, but no difference in CDI6M (HR = 1.17; 95% CI, 0.91-1.50). Differences in CDW6M were not found between the treatment groups. In the base-case cost-effectiveness analysis, natalizumab dominated fingolimod (0.302 higher quality-adjusted life-years [QALYs] and £17,141 lower predicted lifetime costs). Similar cost-effectiveness results were observed across sensitivity analyses. CONCLUSIONS: This MSBase Registry analysis suggests that natalizumab improves clinical outcomes when compared with fingolimod, which translates to higher QALYs and lower costs in UK patients with RES-RRMS.

There are several medications used to treat people with relapsing remitting multiple sclerosis, such as interferon-based therapies (Betaferon/Betaseron (US), Rebif, Avonex, Extavia), glatiramer acetate (Copaxone), teriflunomide (Aubagio), and dimethyl fumarate (Tecfidera), collectively named BRACETD. Other treatments for multiple sclerosis (MS) have a narrower use, such as natalizumab (Tysabri) or fingolimod (Gilenya), among others.This study objective was to assess how well natalizumab and fingolimod helped treating MS (clinical effectiveness) and subsequently estimate what the cost of these treatments is in comparison to the benefit they bring to people with rapidly evolving severe MS that use them in the United Kingdom (UK) (cost-effectiveness).We used an international disease registry (MSBase), which collects clinical data from people with MS in various centers around the world to compare the effectiveness of natalizumab, fingolimod and BRACETD treatments. We used a technique called propensity score matching to obtain results from comparable patient groups. People treated with natalizumab had better disease control, namely with fewer relapses and higher improvement on their disability level, than patients on fingolimod or BRACETD. Conversely, there were no differences between each group of people on a measure called disability worsening.Based on these clinical results, we built an economic model that simulates the lifetime costs and consequences of treating people with MS with natalizumab in comparison with fingolimod. We found that using natalizumab was less costly and was more effective compared to using fingolimod in UK patients.

Role of IL-28B and inosine triphosphatase polymorphisms in efficacy and safety of Peg-Interferon and ribavirin in chronic hepatitis C compensated cirrhosis with and without oesophageal varices.

Genetic factors can influence the outcome of antiviral therapy in chronic hepatitis C (HCV). We evaluated the role of interleukin-28B single nucleotide polymorphisms (SNPs) and inosine triphosphatase (ITPA) gene variants in HCV cirrhosis treated with Peg-Interferon and ribavirin. A prospective cohort of 233 patients with compensated cirrhosis received 1-1.5 µg/kg/week of Peg-Interferon alpha-2b plus 1000-1200 mg/day of RBV for 48 weeks. A sustained virologic response (SVR) was achieved in 27% of patients. On multivariate logistic analysis, the absence of oesophageal varices (OR 3.64 CI 95% 1.27-10.44 P = 0.016), infection with genotype 2 or 3 (OR 4.06, CI 95% 1.08-15.26, P = 0.038), C/C alleles of rs12979860 SNP (OR 7.04, CI 95% 2.40-20.72, P < 0.001) and rapid virologic response (RVR) (OR 78.29, CI 95% 16.07-381.29, P < 0.001) were independently associated with SVR. Patients who experienced post-treatment relapse received lower total doses of Peg-Interferon (52.0 ± 15.8 µg/kg vs 65.7 ± 13.3 µg/kg, P < 0.001) and lower total dose of RBV (3829 ± 1210 mg vs 4709 ± 954 mg, P < 0.001) than patients who achieved an SVR. ITPA variants predictive of high ITPase activity were associated with reduction of haemoglobin ≥3 g/dL in the first 4 weeks (P < 0.001), and with reduction of haemoglobin <10 g/dL (P = 0.03) on treatment. In conclusion, combination therapy with Peg-Interferon and RBV in patients with HCV cirrhosis must be guided by virus genotype, severity of portal hypertension, favourable IL-28B polymorphisms and ITPA variants, and RVR on treatment.

Stick-slip sliding of water drops on chemically heterogeneous surfaces.

We present a comprehensive study of water drops sliding down chemically heterogeneous surfaces formed by a periodic pattern of alternating hydrophobic and hydrophilic stripes. Drops are found to undergo a stick-slip motion whose average speed is an order of magnitude smaller than that measured on a homogeneous surface having the same static contact angle. This motion is the result of the periodic deformations of the drop interface when crossing the stripes. Numerical simulations confirm this view and are used to elucidate the principles underlying the experimental observations.

Biological markers in cerebrospinal fluid for axonal impairment in multiple sclerosis: acetylcholinesterase activity cannot be considered a useful biomarker.

An impairment of the cholinergic system activity has been demonstrated in multiple sclerosis (MS). The correlation between the cholinergic system and the cognitive dysfunction in MS has led to studies on the use of acetylcholinesterase inhibitors (AChEI). The acetylcholinesterase (AChE), essential enzyme for the regulation of turnover of acetylcholine, can be considered the most important biochemical indicator of cholinergic signaling in the nervous system. Besides its catalytic properties, AChE has a crucial role in the regulation of the immune function. Based on the role of the AChe in the regulation of cholinergic signaling in the nervous system, the aim of the present study is to evaluate the activity of AChE in different pathological conditions: MS, other inflammatory neurological disorders (OIND) and non-inflammatory neurological disorders (NIND). We measured AChE activity in CSF samples obtained from 34 relapsing-remitting MS patients and, as controls, 40 patients with other inflammatory neurological disorders (OIND) and 40 subjects with other non-inflammatory neurological disorders (NIND). Fluorimetric detection of the AChE in MS patients and in the controls showed no statistically significant differences: 1.507 ± 0.403 nmol/ml/min in MS patients, 1.484 ± 0.496 nmol/ml/min in OIND and 1.305 ± 0.504 nmol/ml/min in NIND. Similar results were obtained in another recent study, using a different method. Further studies must be conducted on a larger number of patients, with different degrees of cognitive impairment. However, AChE measured in CSF can probably not be considered a useful biomarker for the assessment of the functional alterations of cholinergic system in pathological conditions.

Viral sequence analysis of occult HBV infection and its reactivation in immunosuppressed patients.

Mechanisms associated with reactivation of hepatitis B virus (HBV) in patients with occult HBV infection (OBI) remain unclear. In some cases immunosuppression is an enhancer of viral replication. However, not all patients with OBI who undergo immunosuppression experience reactivation. This study explores the role of viral heterogeneity as a determinant of occult HBV reactivation. HBV genotype, mutation patterns and quasispecies were assessed by sequencing the PreS/S region of 16 patients with OBI undergoing chemotherapy, 3 of whom experienced a OBI reactivation. The latter were also assessed at the time of reactivation. Phylogenetic analysis identified low nucleotide and amino acid diversity rates. There were no differences in the viral quasispecies, or common mutation patterns, detected between patients who underwent reactivation of OBI, and those who did not. Furthermore, upon reactivation, the quasispecies evolved towards a loss of most of the variants present during the initial OBI stage, probably representing the fittest version of the virus. The genetic variability of HBV alone did not account for the transition from occult to overt infection, which appears to be governed principally by the host immune response.