District-Wide Herd Sanitation and Eradication of Intramammary Staphylococcus aureus Genotype B Infection in Dairy Herds in Ticino, Switzerland.

The present study demonstrates successful herd sanitation and eradication of contagious mastitis caused by Staphylococcus aureus genotype B (S. aureus GTB) in an entire Swiss district (Ticino) including 3,364 dairy cows from 168 farms. Herd sanitation included testing of all cows using a highly GTB specific and sensitive qPCR assay, implementation of related on-farm measures, appropriate antibiotic therapy of GTB-positive cows and culling of therapy-resistant animals, respectively. A treatment index was used as an objective criterion to select GTB-positive cows eligible for culling and replacement payment. 62 herds (37%) were initially GTB-positive with a cow prevalence between 10% and 100% and were submitted to sanitation. Twenty mo after the start of the campaign, all these herds were free from S. aureus GTB, whereby 73% of them were sanitized during the first 7 mo. At the cow level, a total of 343 animals were infected. 50 of them were immediately culled and financially compensated based on their treatment index value. The remaining 293 cows were intramammarily treated with antibiotics either during lactation using the combination of cephalexin-kanamycin or penicillin-gentamicin or at dry-off using cloxacillin. Out of these cows, 275 (93.9%) were treated successfully meaning that their milk was twice GTB-negative by qPCR after therapy. For lactational treatment, control samples were taken ≥10 and ≥20 d after treatment, for dry off treatment ≥14 and ≥24 d after parturition. Neither lactation number nor SCC before treatment of the cow nor the type of therapy were associated with therapeutic cure. Using data of 30 GTB-positive and 71 GTB-negative herds (1855 observations), the impact of GTB sanitation on bulk tank milk SCC (BTSCC) was evaluated applying a linear mixed statistical model. In the year before sanitation, BTSCC was always higher in GTB positive than in GTB negative herds. After the start of the campaign, BTSCC declined rapidly in the herds under GTB sanitation and achieved values that no longer differed statistically from those of GTB-free herds after only 2 mo, remaining very similar for the rest of the campaign. The farmers were very satisfied with the outcome of the campaign as all GTB positive herds could be sanitized rapidly, sanitation was sustainable, and milk quality increased.

Penicillin resistance in bovine Staphylococcus aureus: Genomic evaluation of the discrepancy between phenotypic and molecular test methods.

Staphylococcus aureus is a major pathogen in humans and animals. In cattle, it is one of the most important agents of mastitis, causing serious costs in the dairy industry. Early diagnosis and adequate therapy are therefore 2 key factors to deal with the problems caused by this bacterium, and benzylpenicillin (penicillin) is usually the first choice to treat these infections. Unfortunately, penicillin resistance testing in bovine S. aureus strains shows discrepant results depending on the test used; consequently, the best method for assessing penicillin resistance is still unknown. The aim of this study was therefore to find a method that assesses penicillin resistance in S. aureus and to elucidate the mechanisms leading to the observed discrepancies. A total of 146 methicillin-sensitive S. aureus strains isolated from bovine mastitis were tested for penicillin resistance using a broth microdilution [minimum inhibitory concentration (MIC)] and 2 different disk diffusion protocols. Furthermore, the strains were analyzed for the presence of the bla operon genes (blaI, blaR1, blaZ) by PCR, and a subset of 45 strains was also subjected to whole genome sequencing (WGS). Discrepant results were obtained when penicillin resistance of bovine S. aureus was evaluated by disk diffusion, MIC, and PCR methods. The discrepancies, however, could be fully explained by WGS analysis. In fact, it turned out that penicillin resistance is highly dependent on the completeness of the bla operon promotor: when the bla operon was complete based on WGS analysis, all strains showed MIC ≥1 µg/mL, whereas when the bla operon was mutated (31-nucleotide deletion), they were penicillin sensitive except in those strains where an additional, bla operon-independent resistance mechanism was observed. Further, WGS analyses showed that penicillin resistance is truly assessed by the MIC assay. In contrast, caution is required when interpreting disk diffusion and PCR results.

Staphylococcus aureus adlb gene is associated with high prevalence of intramammary infection in dairy herds of northern Italy: A cross-sectional study.

Staphylococcus aureus is a major mastitis pathogen in dairy cattle worldwide, responsible for substantial economic losses. Environmental factors, milking routine, and good maintenance of milking equipment have been described as important factors to prevent intramammary infections (IMI). Staphylococcus aureus IMI can be widespread within the farm or the infection can be limited to few animals. Several studies have reported that Staph. aureus genotypes differ in their ability to spread within a herd. In particular, Staph. aureus belonging to ribosomal spacer PCR genotype B (GTB)/clonal complex 8 (CC8) is associated with high within-herd prevalence of IMI, whereas other genotypes are generally associated with individual cow disease. The adlb gene seems to be strictly related to Staph. aureus GTB/CC8, and is a potential marker of contagiousness. We investigated Staph. aureus IMI prevalence in 60 herds in northern Italy. In the same farms, we assessed specific indicators linked to milking management (e.g., teat condition score and udder hygiene score) and additional milking risk factors for IMI spread. Ribosomal spacer-PCR and adlb-targeted PCR were performed on 262 Staph. aureus isolates, of which 77 underwent multilocus sequence typing. In most of the herds (90%), a predominant genotype was identified, especially Staph. aureus CC8 (30%). In 19 of 60 herds, the predominant circulating Staph. aureus was adlb-positive and the observed IMI prevalence was relevant. Moreover, the adlb gene was detected only in genotypes of CC8 and CC97. Statistical analysis showed a strong association between the prevalence of Staph. aureus IMI, the specific CCs, and carriage of adlb, with the predominant circulating CC and presence of the gene alone explaining the total variation. Interestingly, the difference in the odds ratio obtained in the models for CC8 and CC97 suggests that it is carriage of the adlb gene, rather than the circulation of these CCs per se, that leads to higher within-herd prevalence of Staph. aureus. In addition, the model showed that environmental and milking management factors had no or minimal effect on Staph. aureus IMI prevalence. In conclusion, the circulation of adlb-positive Staph. aureus strains within a herd has a strong effect on the prevalence of IMI. Thus, adlb can be proposed as a genetic marker of contagiousness for Staph. aureus IMI in cattle. However, further analyses using whole-genome sequencing are required to understand the role of genes other than adlb that may be involved in the mechanisms of contagiousness of Staph. aureus strains associated with high prevalence of IMI.

The nature, severity and causes of medication incidents from an Australian community pharmacy incident reporting system: The QUMwatch study.

AIMS: Most research into medication safety has been conducted in hospital settings with less known about primary care. The aim of this study was to characterise the nature and causes of medication incidents (MIs) in the community using a pharmacy incident reporting programme. METHODS: Thirty community pharmacies participated in an anonymous or confidential MI spontaneous reporting programme in Sydney, Australia. The Advanced Incident Management System was used to record and classify incident characteristics, contributing factors, severity and frequency ratings. RESULTS: In total, 1013 incidents were reported over 30 months, 831 of which were near misses while 165 reports involved patient harm. The largest proportion of cases pertained to patients aged >65 years (35.7%). Most incidents involved errors during the prescribing stage (61.1%), followed by dispensing (25.7%) and administration (23.5%), while some errors occurred at multiple stages (17.9%). Systemic antibacterials (12.2%), analgesics (11.8%) and renin-angiotensin medicines (11.7%) formed the majority of implicated classes. Participants identified diverse and interrelating contributing factors: those concerning healthcare providers included violations to procedures/guidelines (75.6%), rule-based mistakes (55.6%) and communication (50.6%); those concerning patients included cognitive factors (31.9%), communication (25.5%) and behaviour (6.1%). Organisational safety culture and inadequate risk management processes were rated as suboptimal. CONCLUSION: An MI reporting programme can capture and characterise medication safety problems in the community and identify the human and system factors that contribute to errors. Since medicine use is ubiquitous in the community, morbidity and mortality from MIs may be reduced by addressing the prioritised risks and contributing factors identified in this study.

Medication incident recovery and prevention utilising an Australian community pharmacy incident reporting system: the QUMwatch study.

PURPOSE: To identify factors in community pharmacy that facilitate error recovery from medication incidents (MIs) and explore medication safety prevention strategies from the pharmacist perspective. METHODS: Thirty community pharmacies in Sydney, Australia, participated in a 30-month prospective incident reporting program of MIs classified in the Advanced Incident Management System (AIMS) and the analysis triangulated with case studies. The main outcome measures were the relative frequencies and patterns in MI detection, minimisation, restorative actions and prevention recommendations of community pharmacists. RESULTS: Participants reported 1013 incidents with 831 recovered near misses and 165 purported patient harm. MIs were mainly initiated at the prescribing (68.2%) and dispensing (22.6%) stages, and most were resolved at the pharmacy (76.9%). Detection was efficient within the first 24 h in 54.6% of MIs, but 26.1% required one month or longer; 37.2% occurred after the patient consumed the medicine. The combination of specific actions/attributes (85.5%), appropriate interventions (81.6%) and effective communication (77.7%) minimised MIs. An array of remedial actions were conducted by participants including notification, referral, advice, modification of medication regimen, risk management and documentation corrections. Recommended prevention strategies involved espousal of medication safety culture (97.8%), better application of policies/procedures (84.6%) and improvements in healthcare providers' education (79.9%). CONCLUSION: Incident reporting provided insights on the human and organisational factors involved in the recovery of MIs in community pharmacy. Optimising existing safeguards and redesigning certain structures and processes may enhance the resilience of the medication use system in primary care.

Cerebral cortical thickness and gyrification changes in first-episode psychoses and multi-episode schizophrenia.

Cortical thickness (CT) and local gyrification index (LGI) in psychotic disorders may show modifications that relate to clinical course. This observational study aimed to analyse such variables in patients with schizophrenia, compared to healthy controls (HCs). We compared CT and LGI of 18 patients with first-episode psychosis with that of 21 with multi-episode schizophrenia and 16 HCs. CT corrected for false-positive cases (Family-Wise Error Rate) showed a reduction in the multi-episode group compared to HCs in left temporal and parietal, and right temporal, parietal, occipital, and hippocampal cortices. Family-wise corrected LGI was increased in the left inferior and middle frontal cortices, and in the right fusiform gyrus, cingulate, lingual, and parahippocampal gyri in first onset patients compared to HCs. Increased LGI was absent from later stages of psychosis, suggesting that specific CT and LGI alterations may underlie different stages of illness.

Multifunctional and tunable trigate graphene metamaterial with "Lakes of Wada" topology.

Many plasmon-induced transparency (PIT) metamaterials previously reported had limited functions. Their tunabilities were realized by complex discrete structures, which greatly increased the difficulty and cost of device fabrication and adversely affected their resonance characteristics. It is an open question to adjust the Fermi levels of many graphene patterns with only a few in-plane electrodes. We propose and numerically study a novel electrically tunable and multifunctional trigate graphene metamaterial (TGGM) based on the concept of "Lakes of Wada". Benefiting from the trigate regulation, our proposed TGGM turns out to exhibit excellent characteristics, that can not only be used for terahertz band-stop filter, terahertz refractive index sensor, near-field optical switch, slow-light device, but also for double PIT window metamaterial with broad transparency windows and large tunable frequency range.

Short communication: Characterization of Staphylococcus aureus from bulk tank milk of dairy cattle in Lombardy (northern Italy).

Staphylococcus aureus is one of the most important pathogens causing mastitis in cattle, and it is responsible for economic losses in dairy herds worldwide. The PCR amplification of the 16S-23S rRNA intergenic spacer (ribosomal spacer PCR, RS-PCR) allows a rapid classification of the strains in genotypes and genotypic clusters (CL), which are characterized by different epidemiological and clinical properties. Both RS-PCR and multi-locus sequence typing (MLST) were performed on strains isolated from bovine bulk tank milk (BTM) collected from dairy herds located in the Lombardy region (northern Italy), to outline the distribution of Staph. aureus genotypes in this geographical area. Out of 844 examined samples, 398 were positive for Staph. aureus, with a variable count (cfu/mL) Up to 8 colonies from each sample were genotyped. A total of 1,101 Staph. aureus strains were analyzed with RS-PCR, and only a selection of them (n = 86), in relation to their frequency and geographical origin, underwent MLST. This study revealed 8 major genotypic clusters (CLB, CLC, CLR, CLS, CLI, CLF, CLAO, and CLZ), of which Staph. aureus CLB (29.3%) was the most common. Samples of BTM positive for CLB had a Staph. aureus cfu/mL count significantly higher than the non-CLB positive ones. Our MLST analysis showed genotypes already known as bovine-associated in literature, such as clonal complexes CC8, CC97, and CC151. The same selection of 86 strains was also analyzed for the presence of the adlb gene, which was recently proposed as a possible marker of contagiousness. Most Staph. aureus belonging to CLB or CC8 carried the adlb gene (85%), whereas this gene was detected in only 9% of non-CLB strains (CLAA, CLBI, CLBJ, CLS). In conclusion, the present study confirms that Staph. aureus CLB, which is recognized as a contagious genotype, is a particularly relevant agent of intramammary infection in dairy cows in Lombardy, and indirectly supports the idea that adlb can be a possible marker of contagiousness of isolates.

Natural history of a cohort of ABCD1 variant female carriers.

BACKGROUND AND PURPOSE: The therapeutic scenario of X-linked adrenoleukodystrophy (X-ALD) is rapidly changing. Whereas the disease is well characterized in men, the condition remains to be fully clarified in women carrying ATP binding cassette subfamily D member 1 (ABCD1) variants. Specifically, data on clinical progression are needed, in order to recommend any appropriate management. The objective of this study was to outline the natural history of a cohort of untreated ABCD1 heterozygous female carriers. METHODS: Longitudinal data from a single-center population of 60 carriers were retrospectively reviewed. Demographics, anthropometrics, serum very long chain fatty acid (VLCFA) levels, clinical parameters and the Adult ALD Clinical Score (AACS) were collected from every recorded visit in a 7-year period and analyzed to define the phenotype modifications, to determine factors associated with clinical features, and to estimate the annual progression rate and the subsequent sample size for interventional trials. RESULTS: Thirty-two patients were eligible for the study, and 59.4% were symptomatic at baseline. Clinical severity worsens with age which increases risk of symptom onset, the cut-off of 41 years being crucial for phenoconversion. VLCFA levels were not predictive and did not change over time. Symptomatic carriers were followed up for 3.45 ± 2.1 years. The AACS increased at an annual rate of 0.24 points. The estimated sample size for 30% reduction in annual progression at 80% power was 272. CONCLUSIONS: This study provides data on the natural disease progression of untreated ABCD1 heterozygous female carriers, demonstrating the relevance of aging. The estimated annual increase of the AACS will be useful for future interventional studies.

Analysis of lip pigmentations by reflectance confocal microscopy: report of two cases.

Oral mucosa pigmentations belong to a heterogeneous variety of lesions, which are usually divided into two groups: exogenous or endogenous pigmentations. The pigmented lesions most frequently found in the oral mucosa are the amalgam tattoo, the melanotic macula and the nevus. All these lesions may affect every part of the oral mucosa, and they may represent a hard diagnostic challenge for the clinician; the clinical objective examination is not sufficient to make a correct diagnosis. Reflectance Confocal Microscopy provides a real-time microscopic evaluation of tissue layers, and is widely considered a useful auxiliary tool in monitoring skin and mucosa lesions. In this context, Reflectance Confocal Microscopy imaging is a valid aid in the management of oral mucosa pigmented lesions, to corroborate and support the diagnostic process.

Analysis of oral mucosa erosive-ulcerative lesions by reflectance confocal microscopy.

In vivo Reflectance Confocal Microscopy (RCM) allows to optically biopsy vital tissues, non-invasively and in real time. It results in horizontal virtual slices at a microscopic resolution and correlating with conventional histopathology. The aim of the present work is to describe RCM cellular and architectural findings in oral mucosae affected by erosive-ulcerative diseases, thus highlighting in vivo the wellknown histological peculiarities. A series of conventionally diagnosed Recurrent Aphthous stomatitis (RAS) and Pemphigus Vulgaris (PV) erosive and/or ulcerative oral lesions underwent RCM imaging to establish the application of RCM imaging to this kind of inflammatory non-tumoral lesions. A total of 12 RAS-related lesions and 8 PV-related lesions were considered. RCM imaging was capable to visualize their microscopic peculiarities, mainly inflammatory infiltrate, vessel dilation (RAS) and acantholytic cells, intraepithelial clefts and inflammatory cell carpets (PV). Despite RCM may result unnecessary to diagnose oral lesions referred to RAS and PV, its capability to highlight their main microscopic features could be advantageously used to monitor the healing or worsening of the clinical situation as well as the responsiveness/refractoriness to therapy.

Association between denture stomatitis, candida species and diabetic status.

Candida species are commensal yeasts of the oral cavity, which, under predisposing systemic and/or local circumstances, are responsible for a wide variety of clinical manifestations, globally known as oral candidiasis. Candida-associated denture stomatitis is an oral candidiasis particularly affecting the oral mucosa covered by a dental prosthesis, with several degree of severity. Diabetics suffer oral candidiasis more frequently than healthy individuals do and if they are denture wearers, the risk increases. Since various controversies still remain regarding the interrelationship among diabetes, oral Candida spp. strains involved in denture stomatitis and the presence of dentures, the present review aims to investigate the differences in Candida species frequencies and degree of denture stomatitis severity existing among diabetic and non- diabetic individuals, with and without dentures.

Topical toluidine blue-mediated photodynamic therapy for the treatment of oral lichen planus.

Photodynamic Therapy (PDT) is a minimally invasive approach that has shown promising results in management of oral, head and neck lesions. PDT can be used alone or in combination with other conventional treatments (surgery, chemotherapy, radiotherapy). Oral Lichen Planus (OLP) is a mucosal and cutaneous chronic disease characterized by an autoimmune insult of basal keratinocytes. We aim to evaluate the feasibility of topical toluidine blue-mediated PDT for the treatment of oral cavity multifocal homogeneous white lesions by oral lichen planus without dysplastic features.

Hymenoptera Venom Allergy: Management of Children and Adults in Clinical Practice.

Hymenoptera venom allergy is an epidemiologically underestimated condition and a major cause of morbidity worldwide. Preventing future allergic reactions in patients who experience a systemic reaction is based on the correct management of the emergency followed by an accurate diagnosis, prescription of adrenaline autoinjectors, and, where indicated, specific venom immunotherapy. Some epidemiological studies highlight our poor knowledge of this disease and the frequent inadequacy of its management. Moreover, they emphasize the importance of such a life-saving treatment as specific immunotherapy. The availability of high-quality hymenoptera venom extracts for diagnostic and therapeutic use has dramatically improved the prognosis and quality of life of allergic patients. Subcutaneous venom immunotherapy is currently the most effective form of allergen-based immunotherapy, with a carry-over effect lasting up to several years after its interruption. This report on the management of hymenoptera venom-allergic children and adults was prepared by a panel of Italian experts. The main objective of this consensus document is to review the scientific evidence related to diagnosis, therapy, and management of patients allergic to hymenoptera venom. Thus, we can improve our knowledge of the disease and promote good clinical practices. The present document provides practical suggestions for correct diagnosis, prescription of emergency therapy and immunotherapy, and strategies for patient care.

The unpredictability of seasonal variations in serum vitamin D levels in children with asthma and/or rhinitis.

BACKGROUND: Some studies have showed that seasonality is an important determinant of vitamin D (vitD) status. OBJECTIVE: We evaluated whether there are differences in individual trends of serum vitD level over one year in asthmatic and rhinitic children. MATERIALS AND METHODS: Ninety-two asthmatic and rhinitic paediatric patients were followed up for one year and their serum vitD level was detected at three-month intervals, once in each season. RESULTS: We observed higher vitD levels at the end of summer and lower at the end of winter. However, the individual seasonal trend was very variable and unpredictable. If it is true that in a given season the majority of patients followed one direction (increase or decrease of serum vitD levels), nevertheless a substantial percentage behaved differently and unpredictably. For example, at the end of spring, 70% of patients showed an increase in serum vitD levels, but 30% showed a decrease. In addition, five individuals had a value ≥50ng/ml in September and showed serum vitD levels ≥30ng/ml throughout the year; 16 patients presented vitD value ≥40ng/ml in September and always had ≥20ng/ml in the other months. CONCLUSIONS: The wide and unpredictable variability of the individual trend of serum vitD levels should be taken into account before deciding whether or not a drug supplementation is appropriate.

Yogurt is tolerated by the majority of children with IgE-mediated cow's milk allergy.

BACKGROUND: Children with IgE-mediated cow's milk allergy (IgE-CMA) with gastrointestinal symptoms tolerate yogurt at 100%. Yogurt tolerance in children with IgE-CMA with urticaria and anaphylaxis was 7%. METHODS: We enrolled children with IgE-CMA with cutaneous, respiratory, gastrointestinal and anaphylactic symptoms. All performed prick by prick (PbP) and oral food challenge (OFC) with yogurt. Some children performed also an OFC with CM mixed with wheat flour and baked, baked liquid CM, parmesan. RESULTS: 34 children were enrolled, 31/34 (91%) with systemic adverse reaction after ingestion of CM (systemic CMA), 3/34 (9%) with isolated contact urticaria (ICU CMA). PbP with yogurt was negative only in one patient. OFC with yogurt was passed (that is, the OFC was negative) by 20/31 (64%) of the children with systemic CMA. 10/11 (91%) of the patients who failed OFC (that is, the OFC was positive) with yogurt were positive to SPT with casein vs. 8/20 (40%) of the patients who passed it (p=0.018). None of the 19 children who passed OFC with yogurt failed all OFC with processed CM forms other than yogurt that tested vs. 4/8 among those who failed OFC with yogurt (p=0.006). The rub test with yogurt was negative in 1/3 (33%) of the patients with ICU CMA. CONCLUSIONS: The results of our study are placed alongside others already present in the literature and concerning other methods of processing CM proteins and help to reduce the dietary restrictions of the majority of children with systemic IgE-CMA.

Cooking influence in tolerance acquisition in egg-induced acute food protein enterocolitis syndrome.

BACKGROUND: Few studies on the age of resolution of Food Protein Induced Enterocolitis Syndrome (FPIES) induced by solid foods are available. In particular, for FPIES induced by egg, the mean age of tolerance acquisition reported in the literature ranges from 42 to 63 months. OBJECTIVE: We have assessed whether the age of tolerance acquisition in acute egg FPIES varies depending on whether the egg is cooked or raw. METHODS: We conducted a retrospective and multicentric study of children with diagnosis of acute egg FPIES seen in 10 Italian allergy units between July 2003 and October 2017. The collected data regarded sex, presence of other allergic diseases, age of onset of symptoms, kind and severity of symptoms, cooking technique of the ingested egg, outcome of the allergy test, age of tolerance acquisition. RESULTS: Sixty-one children with acute egg FPIES were enrolled, 34 (56%) males and 27 (44%) females. Tolerance to cooked egg has been demonstrated by 47/61 (77%) children at a mean age of 30.2 months. For 32 of them, tolerance to raw egg has been demonstrated at a mean age of 43.9 months. No episodes of severe adverse reaction after baked egg ingestion have been recorded. CONCLUSIONS: It is possible to perform an OFC with baked egg, to verify the possible acquisition of tolerance, at about 30 months of life in children with acute egg FPIES.

Predictive value of the number of adverse reaction episodes for the IgE-mediated food allergy diagnosis.

INTRODUCTION AND OBJECTIVES: The reproducibility of the adverse reaction increases the suggestiveness of a history of food allergy. However, the positive predictive value (PPV) of multiple adverse reaction episodes for the diagnosis of IgE-mediated food allergy is not known. This evaluation was the objective of our study. PATIENTS AND METHODS: We retrospectively studied 180 children with a history of non-anaphylactic adverse reactions after the ingestion of a food. All children had the prick test positive for the offending food and performed the oral food challenge (OFC) within 12 months after the last adverse reaction episode (ARE). We have evaluated whether increasing the number of ARE increased the probability that the OFC would be positive (failed). RESULTS: 93 patients (52%) presented one ARE, 49 (27%) presented two ARE, 24 (13%) presented three ARE, 14 (8%) patients presented≥four ARE. The OFC was positive in 94/180 (52%). The outcome of the OFC was found to be positively correlated with the number of ARE (OR=1.56; 95% CI=1.16-2.09; p=0.003). A PPV=100% was observed with a number of ARE≥five. CONCLUSIONS: The number of ARE is an important predictor of the diagnosis of food allergy, although less than we would have imagined. The number of ARE could be used to increase the predictability of the diagnostic tests currently in use, to define clinical prediction rules alternative to OFC and easy to use in clinical practice.

Transatlantic Crossings: Early neurological exchanges between USA and France.

Transnational exchanges have existed for centuries, with both economic and cultural effects. At the end of the 18th century, in the aftermath of the French Revolution, medical education in France underwent radical innovations, prefiguring the training system now almost universally accepted. This paper presents 19th and early 20th century neurology-related exchanges between the United States (US) and Europe, particularly, Paris, which had become a major medical center and where many US neurologists were trained. We discuss some of the intense neurology-related exchanges between the USA and Europe, notably the role of US neurology founders William Alexander Hammond, Silas Weir Mitchell, Edward Seguin as well as Mauritius-born Charles Edouard Brown-Séquard and a few others. We emphasize the mutual benefits that resulted from such exchanges. In later years, the trend reversed with many foreigners, particularly Europeans coming to improve their knowledge in the US. More recently, a shared pattern of travel and enrichment is occurring despite current threats caused by isolationism and undue stress on local identity.

Laser direct writing of graphene nanostructures beyond the diffraction limit by graphene oxidation.

The fabrication ability of graphene nanostructures is the cornerstone of graphene-based devices, which are of particular interest because of their broad optical response and gate-tunable properties. Here, via laser-induced redox reaction of graphene and silica, we fabricate nano-scale graphene structures by femtosecond laser direct writing. The resolution of destructed graphene lines is far beyond the diffraction limit up to 100 nm with a precision as small as ± 7 nm. Consequently, graphene nanostructures are fabricated precisely and excellent plasmon responses are detected. This novel fabrication method of graphene nanostructures has the advantages of low costs, high efficiency, maskless and especially high precision, which would pave the way for practical application of graphene-based optical and electronic devices.