SWI as an Alternative to Contrast-Enhanced Imaging to Detect Acute MS Lesions

BACKGROUND AND PURPOSE

Acute inflammatory activity of MS lesions is traditionally assessed through contrast-enhanced T1-weighted MR images. The aim of our study was to determine whether a qualitative evaluation of non-contrast-enhanced SWI of new T2-hyperintense lesions might help distinguish acute and chronic lesions and whether it could be considered a possible alternative to gadolinium-based contrast agents for this purpose.

MATERIALS AND METHODS

Serial MR imaging studies from 55 patients with MS were reviewed to identify 169 new T2-hyperintense lesions. Two blinded neuroradiologists determined their signal pattern on SWI, considering 5 categories (hypointense rings, marked hypointensity, mild hypointensity, iso-/hyperintensity, indeterminate). Two different blinded neuroradiologists evaluated the presence or absence of enhancement in postcontrast T1-weighted images of the lesions. The Fisher exact test was used to determine whether each category of signal intensity on SWI was associated with gadolinium enhancement.

RESULTS

The presence of hypointense rings or marked hypointensity showed a strong association with the absence of gadolinium enhancement (P < .001), with a sensitivity of 93.0% and a specificity of 82.9%. The presence of mild hypointensity or isohyperintensity showed a strong association with the presence of gadolinium enhancement (P < .001), with a sensitivity of 68.3% and a specificity of 99.2%.

CONCLUSIONS

A qualitative analysis of the signal pattern on SWI of new T2-hyperintense MS lesions allows determining the likelihood that the lesions will enhance after administration of a gadolinium contrast agent, with high specificity albeit with a moderate sensitivity. While it cannot substitute for the use of contrast agent, it can be useful in some clinical settings in which the contrast agent cannot be administered.

Example of antimicrobial stewardship program in a community hospital in Italy

BACKGROUND

Inappropriate use of antibiotics has caused the emergence of resistant strains of bacteria. The hospital of Alessandria, Italy, implemented an antimicrobial stewardship (AS) pilot program between 2013 and 2015 in the intensive care units (ICUs) and internal medicine departments of Casale Monferrato and Tortona. We aimed to describe the project, results at the end of the intervention, and its strengths and weaknesses.

METHODS

The protocol, designed by the local infection control committee, included three consecutive steps: local guidelines for empirical antibiotic therapy and list of prescription antibiotics with justification, monitoring of antibiotic consumption and antimicrobial resistance trend, and peer-to-peer audit sessions in the wards.

RESULTS

One thousand and eighty-five observations were made, corresponding to 850 patients admitted to the ICUs (16.7%) and internal medicine departments (83.3%). Appropriate antibiotic prescriptions increased by 6.4% between 2013 and 2015. The greatest improvement in appropriate prescriptions was observed for glycopeptides and fluoroquinolones (+17.4% and +16.2%, respectively). We reported 305 inappropriate prescriptions, with the most frequent errors being absence of an infectious process (33.3%), inadequate combination therapy (12.8%), and absence of microbiological investigations (8.5%). A reduced incidence of methicillin-resistant Staphylococcusaureus (MRSA) was also observed (p<0.0037).

CONCLUSIONS

Antimicrobial stewardship programs contribute to improving antibiotic prescription and can be implemented in small community hospitals. Narrower interventions, focused on a single disease or single antibiotic should be encouraged.

Are Lipid Abnormalities Reliable Cardiovascular Risk Factors in Dialysis Patients?

Patients on chronic hemodialysis often present both hyperlipidemia and a high incidence of cardiovascular disease (CVD). Uremic hyperlipidemia has usually been regarded as one of the most important cardiovascular risk factors (CVRF) in these patients. In order to study whether the “uremia-induced” lipid abnormalities are actually associated with evidence of uremic CVD, and consequently may be considered reliable CVRF, 123 patients on chronic dialysis were reviewed for the presence of CVD and, at the same time, examined for their lipoprotein pattern and other clinical and biochemical variables.

Lipids and lipoproteins did not prove helpful in our study in identifying patients with CVD. Despite the fact that they had been on dialysis for a shorter time, CVD patients were significantly older and had higher blood pressure than patients without CVD. Our data suggest that the uremia-induced lipid abnormalities are not reliable markers of CVD in dialysis patients, and support the hypothesis that dialysis per se does not accelerate the atherosclerotic process in uremic patients

Model-based optimization of parameters for degradation reaction of an organophosphorus pesticide, paraoxon, using CeO2 nanoparticles in water media

Degradation and body surface decontamination is vital to prevent the skin penetration of paraoxon (POX), an organophosphorus pesticide, and victims poisoning. CeO₂ demonstrated a good efficacy for the degradation of POX. The aim of the study was to develop a model which includes the impact of weight of CeO₂, POX and diluent volumes on the degradation kinetics. The modelling was realized with rapid and simple experiments carried out in tubes, in aqueous diluent which contained ions in order to be in accordance with in vitro skin decontamination conditions. CeO₂ had degraded from 5% (in case of 7.5mmol of POX per gram of CeO₂) to 100% (0.002mmol of POX per gram of CeO₂) of POX. Different kinetic models were tested. Using the particle aggregation kinetic model, the simulated and experimental data were in a good accordance. It highlighted the importance of particles aggregation due to salts and consistency of the mix on the degradation efficiency of CeO₂. The model worked also really well to predict the degradation efficiency of CeO₂ powders during in vitro skin experiments. However, it did not correctly forecast with an aqueous decontaminant, containing CeO₂.

THE DECADE OF THE RABiT (2005-15)

The RABiT (Rapid Automated Biodosimetry Tool) is a dedicated Robotic platform for the automation of cytogenetics-based biodosimetry assays. The RABiT was developed to fulfill the critical requirement for triage following a mass radiological or nuclear event. Starting from well-characterized and accepted assays we developed a custom robotic platform to automate them. We present here a brief historical overview of the RABiT program at Columbia University from its inception in 2005 until the RABiT was dismantled at the end of 2015. The main focus of this paper is to demonstrate how the biological assays drove development of the custom robotic systems and in turn new advances in commercial robotic platforms inspired small modifications in the assays to allow replacing customized robotics with 'off the shelf' systems. Currently, a second-generation, RABiT II, system at Columbia University, consisting of a PerkinElmer cell::explorer, was programmed to perform the RABiT assays and is undergoing testing and optimization studies.

In Vitro Effects of Aminobisphosphonates on Vγ9Vδ2 T Cell Activation and Differentiation

In this study we have evaluated the in vitro effects of four different aminobisphosphonates, alendronate, risedronate, neridronate and zoledronate, on Vγ9Vδ2 T cell activation and differentiation. All tested aminobisphosphonates induce an IL-2-dependent activation and expansion of Vγ9Vδ2 T lymphocytes in primary PBMC cultures of healthy donors. Most notably, they also determine a different distribution of Vγ9Vδ2 T cell subsets, with decrease of Tnaive and TCM cells and increase of TEM and TEMRA Vγ9Vδ2 cells, indicating that in vitro treatment with aminobisphosphonates induces Vγ9Vδ2 T lymphocytes to differentiate towards an effector/cytotoxic phenotype. Accordingly, Vγ9Vδ2 T lymphocytes cultured with aminobisphosphonates and IL-2 showed a major content of IFN-γ and acquired the ability to kill tumor target cells.

Effects of short-term manipulation of serum FFA concentrations on left ventricular energy metabolism and function in patients with heart failure: no association with circulating bio-markers of inflammation

BACKGROUND AND AIMS

We wanted to assess the effects of short-term changes in serum free fatty acids (FFAs) on left ventricular (LV) energy metabolism and function in patients with heart failure and whether they correlated with circulating markers of inflammation.

METHODS AND RESULTS

LV function and phosphocreatine (PCr)/ATP ratio were assessed using MR imaging (MRI) and 31P magnetic resonance spectroscopy (MRS) in 11 men with chronic heart failure in two experimental conditions 7 days apart. Study 1: MRI and 31P-MRS were performed before and 3-4 h after i.v. bolus + continuous heparin infusion titrated to achieve a serum FFA concentration of 1.20 mM. Study 2: The same protocol was performed before and after the oral administration of acipimox titrated to achieve a serum FFA concentration of 0.20 mM. Serum concentrations of IL6, TNF-α, PAI-1, resistin, visfatin and leptin were simultaneously assessed. Serum glucose and insulin concentrations were not different between studies. The PCr/ATP ratio (percent change from baseline: +6.0 ± 16.9 and -16.6 ± 16.1 % in Study 1 and Study 2, respectively; p = 0.005) and the LV ejection fraction (-1.5 ± 4.0 and -6.9 ± 6.3 % in Study 1 and Study 2, respectively; p = 0.044) were reduced during low FFA when compared to high FFA. Serum resistin was higher during Study 1 than in Study 2 (p < 0.05 repeated measures ANOVA); meanwhile, the other adipocytokines were not different.

CONCLUSION

FFA deprivation, but not excess, impaired LV energy metabolism and function within hours. Cautions should be used when sudden iatrogenic modulation of energy substrates may take place in vulnerable patients.

Bladder urothelial neoplasms in pediatric age: experience at three tertiary centers

INTRODUCTION

Urothelial bladder neoplasms (UBN) typically occur in patients in their sixth or seventh decade of life while they are infrequent in children and young adults. They occur in 0.1-0.4% of the population in the first two decades of life. Their management is controversial and paediatric guidelines are currently unavailable.

OBJECTIVE

To further expound the available data on the outcome of patients younger than 18 year old diagnosed with UBN.

STUDY DESIGN

We retrospectively reviewed the files of all the consecutive paediatric patients with UBN treated in three tertiary paediatric urology units from January 1999 to July 2013. Lesions were classified according to the 2004 WHO/ISUP criteria as urothelial papillomas (UP), papillary urothelial neoplasm of low malignant potential (PUNLMP), low-grade urothelial carcinoma (LGUC), and high-grade urothelial carcinoma (HGUC).

RESULTS

The table shows the results. Management after TURB varied among centres. One centre recommended only follow-up US at increasing intervals whereas another follow-up US plus urine cytologies and endoscopies, every three months in the first year, and at increasing intervals thereafter. After a median follow-up of 5 years (range 9 months-14.5 years), none of the patients showed disease recurrence or progression.

DISCUSSION

UBN is an uncommon condition in children and adolescents and, unlike in adults, its incidence, follow-up and outcome still controversial. Paediatric guidelines are currently lacking and management varies among centres. Gross painless haematuria is the most common presenting symptom. Therefore, this symptom should never be underestimated. US is generally the first investigation and additional imaging seems unnecessary. TURB often allows for complete resection. Lesions are generally solitary, non-muscle invasive, and low-grade (mainly UP and PUNLMP). Ideal follow-up protocol is the most controversial point. Reportedly, recurrence or progression during follow-up is uncommon in patients under 20 years, recurrence rate 7% and a single case of progression reported so far. Accordingly, a follow-up mainly based on serial US might be considered in this age group compared to adults where also serial endoscopies and urine cytologies are recommended. In the selection of the follow-up investigations, it should also be taken into consideration that urine cytology has a low sensibility in the detection of low-grade lesions while cystoscopy in young patients requires a general anaesthesia and hospitalization, and carries an increased risk of urethral manipulation.

CONCLUSION

UBN is a rare condition in children. Ultrasound is generally accurate in order to visualize the lesion, and TURB can treat the condition. Lesions are generally low-grade and non-muscle invasive, but high-grade lesions can also be detected. In present series, after TURB, follow-up US monitoring at increasing intervals was used at all centres, follow-up cystoscopies were added in two centres, but with different schedules. Urine cytologies were considered only at one centre. After a median follow-up of 5 years (range 9 months-14.5 years), none of the patients showed recurrence or progression of the disease.

Incretins or anti-incretins? A new model for the "entero-pancreatic axis"

The role of incretins in glucose homeostasis is well known. Yet, in recent years, the sustained weight loss and rapid glycemic control following bariatric surgery has challenged our understanding of the intestinal-pancreatic interaction. This in turn led to the introduction of metabolic surgery, an innovative medical discipline in which a surgical manipulation of the gastrointestinal tract (e. g., through a Roux-en-Y gastric bypass, RYGB, or Bilio-Pancreatic-Diversion, BPD) yields a sustained remission of diabetes mellitus. The pathophysiological background of this metabolic effect is, amongst other things, based on the anti-incretin theory. This theory postulates that in addition to the well-known incretin effect, nutrient passage through the GI-tract could also activate negative feedback mechanisms (anti-incretins) to balance the effects of incretins and other postprandial glucose-lowering mechanisms (i. e., suppression of ghrelin, glucagon, and hepatic glucose production via activation of nutrient sensing). This in turn prevents postprandial hyperinsulinemic hypoglycemia. The bypass of the duodenum, the entire jejunum and the first portion of the ileum by BPD induce normalization of peripheral insulin sensitivity, while the bypass of a shorter intestinal tract by RYGB mainly improves the hepatic insulin sensitivity. In addition, RYGB greatly increases insulin secretion. Therefore, metabolic surgery highlights the important role of the small intestine in glucose homeostasis, while until few years ago, it was only the pancreas and the liver that were thought to represent the regulatory organs for glucose disposal.

Thermoplastic Foams from Zein and Gelatin

The aim of this study was to characterize the foaming of natural proteins as thermoplastic polymers. In particular, two proteins, one of vegetal origin, zein, and one of animal origin, gelatin, were processed to achieve thermoplastic polymers, and subsequently foamed by a gas foaming batch process. The effects of suitable plasticizing additives and melt-mixing process on the thermal and mechanical properties of the thermoplasticized proteins were evaluated to assess the thermoplastic characteristics of these materials. Furthermore, selected protein/plasticizers systems were foamed with mixtures of CO2 and N2 as blowing agents, in a batch foaming apparatus, at different temperatures, pressures and pressure drop rates, to evaluate the processing window and the final properties of the foams. Foams with densities of 0.1 g/cm3 and morphologies characterized by uniform distributions of cells with 10 μm diameters were obtained. Results indicated the suitability of zein and gelatin for being processed with classical thermoplastic processing technologies including melt mixing and foaming and their potentials as biodegradable polymers.

Tuning the microstructure and biodegradation of three-phase scaffolds for bone regeneration made of PCL, Zein, and HA

The aim of this study has been the design of novel multi-phase porous scaffolds with bi-modal pore size distributions and controlled biodegradation rate for bone tissue engineering (bTE), via a gas foaming—leaching approach. Poly( ε-caprolactone) (PCL) has been melt mixed with thermoplastic zein (TZ) and hydroxyapatite particle, to prepare multi-phase PCL—TZ and PCL—TZ—HA composites suitable to be further processed for the fabrication of 3D porous scaffolds. To this aim, these systems have been gas foamed by using CO2 as blowing agent and, subsequently, soaked in H2O to leach out the plasticizer from the TZ. This combined process allows the formation of an interpenetrated micro- and macro-porosity network within the samples. The effect of the different formulations on the micro-structural properties and in vitro biodegradation of the scaffolds has been investigated, and the results correlated to the mechanisms involved in the formation of the bi-modal pore structure. Results demonstrated that the multi-phase nature of the biomaterials prepared as well as their composition significantly affect the micro-structural properties and biodegradation rate of the scaffolds. The optimal selection of the processing conditions may allow for the design of multi-phase 3D porous scaffolds suitable for bTE.

Experimental validation of a reach-and grasp optimization algorithm inspired to human arm-hand control

Taking inspiration from neurophysiological studies on synergies in the human grasping action, this paper tries to demonstrate that it is possible to find a general rule for performing a stable, human-like cylindrical grasp with a robotic hand. To this purpose, the theoretical formulation and the experimental validation of a reach-and-grasp algorithm for determining the optimal hand position and the optimal finger configuration for grasping a cylindrical object with known features are presented. The proposed algorithm is based on the minimization of an objective function expressed by the sum of the distances of the hand joints from the object surface. Algorithm effectiveness has preliminarily been tested by means of simulation trials. Experimental trials on a real arm-hand robotic system have then been carried out in order to validate the approach and evaluate algorithm performance.

NYHA Class II subgrouping: correlation with left ventricular dysfunction questionnaire (LVD-36) and ejection fraction

AIM

NYHA classification divides into four classes. Although subjective and lacking of standardization, NYHA class II is in clinical practice often further subgrouped in IIA and IIB, where IIA class can be defined as dyspnea after running or climbing ≥ 2 ramps of stairs, and IIB class as dyspnea after fast walking or climbing 2 ramps of stairs. Validation of NYHA IIA and IIB sub-grouping was performed with left ventricular dysfunction questionnaire (LVD-36) results and echocardiographic left ventricular ejection fraction.

METHODS

The study includes a total of 127 patients with both systolic and diastolic heart failure (mean age 65 ± 17, range 38-85 years). Sixteen patients were in NYHA class I, 81 patients in NYHA class II (45 in class IIA and 36 in class IIB) and 30 in class III.

RESULTS

In class IIA patients' mean age was 64 ± 9 years, LVD-36 score 31.79 ± 14.06, EF 43 ± 10% (P = ns, P<0.001 and P=ns, respectively, vs. class I patients). In class IIB patients' mean age was 67 ± 10 years, LVD-36 score 48.90 ± 15.51, EF 39 ± 12% (P = ns, P < 0.0001 and P = ns, respectively, vs. IIA patients). In class III patients' mean age was 65 ± 11 years, LVD-36 score 65.17 ± 16.35, EF 32.77 ± 12.91% (P = ns, P < 0.01 and P = ns, respectively, compared with class IIB).

CONCLUSION

NYHA class II sub-grouping appears an accurate method of classification and could represent a further useful tool in monitoring functional capacity of heart failure patients. NYHA class II sub-grouping correlates well with patients functional impairment and can therefore be implemented as an accurate method to better characterize heart failure patients.

Design of porous polymeric scaffolds by gas foaming of heterogeneous blends

One of the challenges in tissue engineering scaffold design is the realization of structures with a pre-defined multi-scaled porous network. Along this line, this study aimed at the design of porous scaffolds with controlled porosity and pore size distribution from blends of poly(epsilon-caprolactone) (PCL) and thermoplastic gelatin (TG), a thermoplastic natural material obtained by de novo thermoplasticization of gelatin. PCL/TG blends with composition in the range from 40/60 to 60/40 (w/w) were prepared by melt mixing process. The multi-phase microstructures of these blends were analyzed by scanning electron microscopy and dynamic mechanical analysis. Furthermore, in order to prepare open porous scaffolds for cell culture and tissue replacement, the TG and PCL were selectively extracted from the blends by the appropriate combination of solvent and extraction parameters. Finally, with the proposed combination of gas foaming and selective polymer extraction technologies, PCL and TG porous materials with multi-scaled and highly interconnected porosities were designed as novel scaffolds for new-tissue regeneration.

Engineered mu-bimodal poly(epsilon-caprolactone) porous scaffold for enhanced hMSC colonization and proliferation

The use of scaffold-based strategies in the regeneration of biological tissues requires that the design of the microarchitecture of the scaffold satisfy key microstructural and biological requirements. Here, we examined the ability of a porous poly(epsilon-caprolactone) (PCL) scaffold with novel bimodal-micron scale (mu-bimodal) porous architecture to promote and guide the in vitro adhesion, proliferation and three-dimensional (3-D) colonization of human mesenchymal stem cells (hMSCs). The mu-bimodal PCL scaffold was prepared by a combination of gas foaming (GF) and selective polymer extraction (PE) from co-continuous blends. The microarchitectural properties of the scaffold, in particular its morphology, porosity distribution and mechanical compression properties, were analyzed and correlated with the results of the in vitro cell-scaffold interaction study, carried out for 21days under static conditions. Alamar Blue assay, scanning electron microscopy, confocal laser scanning microscopy and histological analyses were performed to assess hMSC adhesion, proliferation and 3-D colonization. The results showed that the combined GF-PE technique allowed the preparation of PCL scaffold with a unique multiscaled and highly interconnected microarchitecture that was characterized by mechanical properties suitable for load-bearing applications. Study of the cell-scaffold interaction also demonstrated the ability of the scaffold to support hMSC adhesion and proliferation, as well as the possibility to promote and guide 3-D cell colonization by appropriately designing the microarchitectural features of the scaffold.

Analysis of memory and effector CD8+ T cell subsets in chronic graft-versus-host disease

In humans, the selective depletion of CD8+ cells may prevent GVHD after allogeneic transplantation. These cells can infiltrate and damage target tissues. It is of interest to investigate the phenotypical characteristics and cytotoxic properties of the different CD8+ subsets in cGVHD patients. In a preliminary study we found that patients with cGVHD had a markedly elevated percentage of peripheral blood CCR7-/CD45RA+ cells compared to patients without cGVHD; conversely, the CCR7+/CD45RA+ subsets of CD8+ cells was significantly decreased. In this study, we report in depth on the phenotype of effector T cell subsets in cGVHD patients, as well as their proliferative capability, cytotoxic properties and cellular turnover. We confirm a predominance of effector T cell subsets in cGVHD patients and show that a large fraction of these cells down-regulate CCR7 and re-express CD45RA, thus approaching end-stage differentiation. Moreover CD8+ cells of cGVHD patients have low CD8 coreceptor expression, reduced proliferative potential and a high content of perforin and granzyme A. They also have a lower cell turnover and have more propensity to apoptosis, as demonstrated by BrdU incorporation. Taken together, our findings indicate a perturbation of the balance between naive/memory and effector/CD45RA+ CD8+ T cells, and suggest an involvement of the latter compartment characterized by a high content of cytotoxic equipment, in the pathogenesis of cGVHD.

Calibration of the thermoelastic constants for quantitative thermoelastic stress analysis on composites

The application of thermoelastic stress analysis in composite materials is particularly complicated because of the anisotropy of the material, that determines the thermoelastic constant to be dependent on the direction of the fibers. A further difficulty depends on the constructive stratification of the material, whose mechanical properties vary with the depth from the surface and this causes thermoelastic constants to be dependent on the frequency of the load applied. By using an analytical two layer model, it has been possible to interpret experimental data, thus proposing an explanation of the dependence on the frequency of the measured thermoelastic constants. This has shown that the practical use of the thermoelastic effect for quantitative stress analysis on composites needs constants calibrated at the correct frequency, also considering the thin layer of superficial resin present in every composite material.

Immunomodulating role of bisphosphonates on human gamma delta T cells: an intriguing and promising aspect of their antitumour activity

Vgamma9Vdelta2 T cells have the ability to produce inflammatory cytokines involved in protective immunity against intracellular pathogens and tumours and to display strong cytolytic as well as bactericidal activities. This suggests a direct involvement of Vgamma9Vdelta2 T lymphocytes in immune control of cancer and infections. These observations have recently aided development of novel immunotherapeutic approaches aimed at Vgamma9Vdelta2 T cell activation. Nitrogen-containing bisphosphonates (N-BPs) play a crucial role in Vgamma9Vdelta2 T lymphocyte activation and in the acquisition of effector functions. The preliminary results of these innovative strategies are encouraging. Moreover, compelling evidence in the literature supports the hypothesis that the antitumour effect of bisphosphonates is exerted through direct as well as indirect mechanisms. An additional and not yet well explored mechanism by which N-BPs may display antineoplastic effect is related to their immunomodulatory properties. It is fascinating that N-BPs influence the immune system in various but interrelated ways, being able to enhance the innate and to promote the adaptive immune responses. For all these reasons, Vgamma9Vdelta2 T lymphocytes represent a particularly interesting target for immunotherapeutic protocols based on N-BP administration. All these unexpected effects of N-BPs on the immune system have opened new and intriguing possibilities of therapeutic use for these drugs.

[Medical, social and economics aspects in the sulphur mines in Sicily(1791 - 1964)]

In Sicily the sulphur extraction represented an occasion of economic growth and a development for the dignity of the workers. The "carusi", young boys from 6 to 14 years old, were given up by their parents in return of a hardly payed of loan; it was the so called "soccorso morto" (dead aid). They were submitted to an enormous very hard physical work that caused severe damage to the skeleton and this was the reason of their inability to military service. The anthropometric surveys of "carusi" and pupils highlight for the first ones a reduced increase of the height and for the second ones the presence of "gibbo". For this reasons the inhabitans of Racalmuto were called racalmutesi immiruti" which means that people who lives in Racalmuto were hunchbacked. Nowadays it's possible to say that dietary and nutritional causes determined metabolic damages to the skeleton. A comparison between people who have been declared unable for military service belonged to the two lower clones of farmers and miners showed a lower incidence of the first ones. The law of 1866 on child labour assigned to medical doctors the task of certifying their suitability to work: the first step of normalisation on a medical care basis.

Magnetically Driven Growth of Anthracene Thin Films by Organic Molecular Beam Deposition

The possible use of a static magnetic field during organic molecular beam deposition of thin molecular films for inducing some preferential growth is discussed and the magnetic properties of diamagnetic molecules and molecular crystals are recalled. Considering prototypical materials, namely anthracene molecules and potassium phthalate substrates, which interact and may give rise to polycrystalline films with specific orientations, we show that in the presence of a magnetic field the films display a macroscopic preferential orientation as a result of minimization of the magnetic energy contribution. A very good agreement between the results of optical spectroscopy, atomic force microscopy, and predictions made on the basis of the anisotropic magnetic susceptibility of anthracene is found.