The Effect of Surgical Weight Loss on Cognition in Individuals with Class II/III Obesity.

BACKGROUND: Obesity is a global epidemic and is associated with cognitive impairment and dementia. It remains unknown whether weight loss interventions, such as bariatric surgery, can mitigate cognitive impairment. OBJECTIVES: We aimed to determine the effect of surgical weight loss on cognition in individuals with class II/III obesity. DESIGN: We performed a prospective cohort study of participants who underwent bariatric surgery. At baseline and two years following surgery, participants completed metabolic risk factor and neuropsychological assessments. SETTING: Participants were enrolled from an academic suburban bariatric surgery clinic. PARTICIPANTS: There were 113 participants who completed baseline assessments and 87 completed two-year follow-up assessments (66 in-person and 21 virtual) after bariatric surgery. The mean (SD) age was 46.8 (12.5) years and 64 (73.6%) were female. INTERVENTION: Bariatric surgery. There were 77 (88.5%) participants that underwent sleeve gastrectomy and 10 (11.5%) that underwent gastric bypass surgery. MEASUREMENTS: Cognition was assessed using the NIH toolbox cognitive battery (NIHTB-CB) and the Rey Auditory Verbal Learning Test (AVLT). The primary outcome was the change in NIHTB-CB fluid composite score before and after surgery. RESULTS: The primary outcome, NIHTB-CB composite score, was stable following bariatric surgery (-0.4 (13.9), p=0.81,n=66). Among secondary outcomes, the NIHTB-CB dimensional card sorting test (executive function assessment), improved (+6.5 (19.9),p=0.01,n=66) while the Rey AVLT delayed recall test (memory assessment) declined (-0.24 (0.83),p=0.01,n=87) following surgery. Improvements to metabolic risk factors and diabetes complications were not associated with improvements to NIHTB-CB composite score. The other 4 NIHTB-CB subtests and Rey AVLT assessments of auditory learning and recognition were stable at follow-up. CONCLUSIONS: Following bariatric surgery, the age-adjusted composite cognitive outcome did not change, but an executive subtest score improved. These results suggest that bariatric surgery may mitigate the natural history of cognitive decline in individuals with obesity, which is expected to be faster than normal aging, but confirmatory randomized controlled trials are needed. The decline in delayed recall also warrants further studies to determine potential differential effects on cognitive subtests.

Identification of candidate novel production variants on the Bos taurus chromosome X.

Chromosome X is often excluded from bovine genetic studies due to complications caused by the sex specific nature of the chromosome. As chromosome X is the second largest cattle chromosome and makes up approximately 6% of the female genome, finding ways to include chromosome X in dairy genetic studies is important. Using female animals and treating chromosome X as an autosome, we performed X chromosome inclusive genome-wide association studies in the selective breeding environment of the New Zealand dairy industry, aiming to identify chromosome X variants associated with milk production traits. We report on the findings of these genome-wide association studies and their potential effect within the dairy industry. We identify missense mutations in the MOSPD1 and CCDC160 genes that are associated with decreased milk volume and protein production and increased fat production. Both of these mutations are exonic SNP that are more prevalent in the Jersey breed than in Holstein-Friesians. Of the 2 candidates proposed it is likely that only one is causal, though we have not been able to identify which is more likely.

Microbiome profiles of non-responding and responding paired periodontitis sites within the same participants following non-surgical treatment.

Aim: Periodontitis is a site-specific, chronic disease treated by non-surgical debridement of subgingival plaque. We aimed to determine the microbiome of sites that did not respond to this treatment (NR) compared with paired good responding (GR) sites before and after treatment. Materials and methods: In a longitudinal cohort study, clinical parameters of disease and biological samples were taken prior to and 3 months after treatment. Twelve NR sites from six participants were paired with GR sites within the same participant. Subgingival plaque samples were subjected to bacterial community analysis using 16S rRNA gene sequencing. Results: There were no significant differences in clinical parameters and microbial communities at baseline between GR and NR sites. Bacterial communities in deep pockets were dominated by a small number of species, notably Porphyromonas gingivalis and Treponema denticola. In NR sites three months after treatment there was no significant change in bacterial composition whilst there was a collapse in the abundance of pathobionts in GR sites. Conclusion: NR sites were not identifiable prior to treatment by clinical or microbiological parameters. Treatment failed to disrupt pathogenic bacterial community in NR sites. Targeted suppression of particular species should be considered to initiate community collapse and aid disease resolution.

The association between midwifery staffing levels and the experiences of mothers on postnatal wards: Cross sectional analysis of routine data.

BACKGROUND: Women have consistently reported lower satisfaction with postnatal care compared with antenatal and labour care. The aim of this research was to examine whether women's experience of inpatient postnatal care in England is associated with variation in midwifery staffing levels. METHODS: Analysis of data from the National Maternity Survey in 2018 including 17,611 women from 129 organisations. This was linked to hospital midwifery staffing numbers from the National Health Service (NHS) Workforce Statistics and the number of births from Hospital Episode Statistics. A two-level logistic regression model was created to examine the association of midwifery staffing levels and experiences in post-natal care. RESULTS: The median Full Time Equivalent midwives per 100 births was 3.55 (interquartile range 3.26-3.78). Higher staffing levels were associated with less likelihood of women reporting delay in discharge (adjusted odds ratio [aOR] 0.849, 95% CI 0.753-0.959, p = 0.008), increased chances of women reporting that staff always helped in a reasonable time aOR1.200 (95% CI 1.052, 1.369, p = 0.007) and that they always had the information or explanations they needed aOR 1.150 (95% CI 1.040, 1.271, p = 0.006). Women were more likely to report being treated with kindness and understanding with higher staffing, but the difference was small and not statistically significant aOR 1.059 (0.949, 1.181, p = 0.306). CONCLUSIONS: Negative experiences for women on postnatal wards were more likely to occur in trusts with fewer midwives. Low staffing could be contributing to discharge delays and lack of support and information, which may in turn have implications for longer term outcomes for maternal and infant wellbeing.

Anglo-French neurological interactions in the 19th and early 20th centuries: Societies and Journals.

We have reviewed seminal interactions between British and French physicians prior to and following the establishment of the Paris and London Schools of Neurology from the mid-19th to the early 20th centuries. Our first article focused on British and French physicians, places and events. In this second part of our review we have examined the interactions between British and French Neurological Societies and Journals, including: (1) The Neurological Society of London founded in 1886, which became the Section of Neurology of the Royal Society of Medicine; (2) The Société de Neurologie de Paris founded in 1899, later renamed as The Société Française de Neurologie; (3) The journal Brain and its precursors and successors; (4) The journal Revue Neurologique and its precursors. We illustrate the constructive influence of Anglo-French interactions on the early development of neurology by the distinguished physicians who were corresponding members respectively of the British and French Neurological Societies and the scientific articles published by French authors in Brain and by British scientists in Nouvelle Iconographie de la Salpêtrière, Archives de Neurologie and Revue Neurologique.

The Type IX Secretion System and Its Role in Bacterial Function and Pathogenesis.

Porphyromonas, Tannerella, and Prevotella species found in severe periodontitis use the Type IX Secretion System (T9SS) to load their outer membrane surface with an array of virulence factors. These virulence factors are then released on outer membrane vesicles (OMVs), which penetrate the host to dysregulate the immune response to establish a positive feedback loop of chronic, inflammatory destruction of the tooth's supporting tissues. In this review, we present the latest information on the molecular architecture of the T9SS and provide mechanistic insight into its role in secretion and attachment of cargo proteins to produce a virulence coat on cells and OMVs. The recent molecular structures of the T9SS motor comprising PorL and PorM as well as the secretion pore Sov, together with advances in the overall interactome, have provided insight into the possible mechanisms of secretion. We propose the presence of PorL/M motors arranged in a circle at the inner membrane with bent periplasmic rotors interacting with the PorN protein. At the outer membrane, we envisage a slide carousel model where the PorN protein is driven around a circular track composed of PorK. Cargo proteins are transported by PorN to PorW and the Sov translocon just as slides are rotated to the projection window. Secreted proteins are proposed to then be shuttled along highways consisting of the PorV shuttle protein to an array of attachment complexes distributed around the cell. The cell surface attachment of cargo is a hallmark of the T9SS, and in Porphyromonas gingivalis and Tannerella forsythia, this attachment is achieved via covalent bonding to a linking sugar synthesized by the Wbp/Vim pathway. The cell-surface attached cargo are enriched on OMVs, which are then released from the cell.

Realist evaluation of Schwartz rounds® for enhancing the delivery of compassionate healthcare: understanding how they work, for whom, and in what contexts.

BACKGROUND: Healthcare work is known to be stressful and challenging, and there are recognised links between the psychological health of staff and high-quality patient care. Schwartz Center Rounds® (Rounds) were developed to support healthcare staff to re-connect with their values through peer reflection, and to promote more compassionate patient care. Research to date has focussed on self-report surveys that measure satisfaction with Rounds but provide little analysis of how Rounds 'work' to produce their reported outcomes, how differing contexts may impact on this, nor make explicit the underlying theories in the conceptualisation and implementation of Rounds. METHODS: Realist evaluation methods aimed to identify how Rounds work, for whom and in what contexts to deliver outcomes. We interviewed 97 key informants: mentors, facilitators, panellists and steering group members, using framework analysis to organise and analyse our data using realist logic. We identified mechanisms by which Rounds lead to outcomes, and contextual factors that impacted on this relationship, using formal theory to explain these findings. RESULTS: Four stages of Rounds were identified. We describe how, why and for whom Schwartz Rounds work through the relationships between nine partial programme theories. These include: trust safety and containment; group interaction; counter-cultural/3rd space for staff; self-disclosure; story-telling; role modelling vulnerability; contextualising patients and staff; shining a spotlight on hidden stories and roles; and reflection and resonance. There was variability in the way Rounds were run across organisations. Attendance for some staff was difficult. Rounds is likely to be a 'slow intervention' the impact of which develops over time. We identified the conditions needed for Rounds to work optimally. These contextual factors influence the intensity and therefore degree to which the key ingredients of Rounds (mechanisms) are activated along a continuum, to produce outcomes. Outcomes included: greater tolerance, empathy and compassion for self and others; increased honesty, openness, and resilience; improved teamwork and organisational change. CONCLUSIONS: Where optimally implemented, Rounds provide staff with a safe, reflective and confidential space to talk and support one another, the consequences of which include increased empathy and compassion for colleagues and patients, and positive changes to practice.

Adaptive response of a metal-organic framework through reversible disorder-disorder transitions.

The ultrahigh porosity and varied functionalities of porous metal-organic frameworks make them excellent candidates for applications that range widely from gas storage and separation to catalysis and sensing. An interesting feature of some frameworks is the ability to open their pores to a specific guest, enabling highly selective separation. A prerequisite for this is bistability of the host structure, which enables the framework to breathe, that is, to switch between two stability minima in response to its environment. Here we describe a porous framework DUT-8(Ni)-which consists of nickel paddle wheel clusters and carboxylate linkers-that adopts a configurationally degenerate family of disordered states in the presence of specific guests. This disorder originates from the nonlinear linkers arranging the clusters in closed loops of different local symmetries that in turn propagate as complex tilings. Solvent exchange stimulates the formation of distinct disordered frameworks, as demonstrated by high-resolution transmission electron microscopy and diffraction techniques. Guest exchange was shown to stimulate repeatable switching transitions between distinct disorder states.

Anglo-French neurological interactions in the 19th and early 20th centuries: Physicians, places and events.

The development of neurology as an independent discipline in the mid-19th century was considerably influenced by the almost simultaneous foundation of the Charcot School at the Salpêtrière Hospital in Paris and the National Hospital for the Paralysed and Epileptic and it's School at Queen Square in London in the 1860's. We have reviewed the early interactions between Charcot's school and the leading neurologists at the National Hospital and also discussed their neurological antecedents and subsequent links up to the outbreak of World War 1 in 1914. Earlier interactions involved Trousseau and Duchenne in France and Graves, Todd, Laycock and Allbutt in Britain. The French Brown-Séquard was one of the first two physicians appointed to the National Hospital. Charcot was a frequent visitor to Britain culminating in his influential role in the 1881 International Medical Congress in London. He first suggested the terms "Parkinson's Disease" and "Jacksonian Epilepsy". He attracted numerous British visitors to Paris and his studies of hysteria were influenced by Laycock, Todd and Russell Reynolds. Hughlings Jackson drew upon the anatomical studies of Gratiolet in his interactions with Broca and Charcot which influenced French views on aphasia, epilepsy and cortical localisation. Ball, an Englishman, was the first Professor of mental and brain diseases in Paris in 1877. Bruce in Edinburgh and Kinnier Wilson in London both maintained frequent contacts with Paris, where the latter first presented his studies of hepatolenticular degeneration in 1912. The Entente Cordiale of 1904 led to further interactions with the leading role of the French and British physicians Raymond and Duckworth. Two outstanding British women, Elizabeth Garrett and Blanche Edwards, qualified in Medicine in Paris with neurological interests. Our review emphasises the constructive influence of the French and British Schools on each other and thus on the development of neurology. The French influence was primarily the establishment of the anatomo-clinical method and the use of photographic illustrations in publications. The British School influence was its Clinical Assessment Skills and scientific studies of newly recognised diseases and concepts and its early development of neurosurgery.

Remineralization and fluoride uptake of white spot lesions under dental varnishes.

INTRODUCTION: The aim of this study was to evaluate white spot lesion (WSL) remineralization and fluoride uptake by the application of fluoride varnishes directly onto artificial WSLs in vitro. METHODS: MI varnish containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and 2.26% fluoride and Duraphat varnish containing 2.26% fluoride (no added calcium) were compared with a placebo varnish (no added calcium or fluoride). Two WSLs were prepared in enamel slabs and varnish applied to cover one of the two lesions. Each slab was immersed in artificial saliva for 14 days at 37°C. Mineral content was determined using transverse microradiography and fluoride uptake using electron probe microanalysis. The data were statistically analysed using a linear mixed model. RESULTS: Both MI and Duraphat varnishes significantly remineralized the covered and uncovered WSLs when compared with the placebo varnish (P < 0.001). The WSLs covered with varnish showed greater remineralization than those uncovered. MI varnish produced the highest level of remineralization and significantly greater fluoride uptake (0.44 ± 0.08 wt%) compared with Duraphat (0.24 ± 0.03 wt%) and the placebo varnish (0.06 ± 0.05 wt%). CONCLUSION: Varnish containing fluoride and CPP-ACP was superior to varnish containing fluoride alone in promoting WSL remineralization and fluoride uptake.

Airway management during in-hospital cardiac arrest: An international, multicentre, retrospective, observational cohort study.

AIM: To determine the type of airway devices used during in-hospital cardiac arrest (IHCA) resuscitation attempts. METHODS: International multicentre retrospective observational study of in-patients aged over 18 years who received chest compressions for cardiac arrest from April 2016 to September 2018. Patients were identified from resuscitation registries and rapid response system databases. Data were collected through review of resuscitation records and hospital notes. Airway devices used during cardiac arrest were recorded as basic (adjuncts or bag-mask), or advanced, including supraglottic airway devices, tracheal tubes or tracheostomies. Descriptive statistics and multivariable regression modelling were used for data analysis. RESULTS: The final analysis included 598 patients. No airway management occurred in 36 (6%), basic airway device use occurred at any time in 562 (94%), basic airway device use without an advanced airway device in 182 (30%), tracheal intubation in 301 (50%), supraglottic airway in 102 (17%), and tracheostomy in 1 (0.2%). There was significant variation in airway device use between centres. The intubation rate ranged between 21% and 90% while supraglottic airway use varied between 1% and 45%. The choice of tracheal intubation vs. supraglottic airway as the second advanced airway device was not associated with immediate survival from the resuscitation attempt (odds ratio 0.81; 95% confidence interval 0.35-1.8). CONCLUSION: There is wide variation in airway device use during resuscitation after IHCA. Only half of patients are intubated before return of spontaneous circulation and many are managed without an advanced airway. Further investigation is needed to determine optimal airway device management strategies during resuscitation following IHCA.

Temporal development of the oral microbiome and prediction of early childhood caries.

Human microbiomes are predicted to assemble in a reproducible and ordered manner yet there is limited knowledge on the development of the complex bacterial communities that constitute the oral microbiome. The oral microbiome plays major roles in many oral diseases including early childhood caries (ECC), which afflicts up to 70% of children in some countries. Saliva contains oral bacteria that are indicative of the whole oral microbiome and may have the ability to reflect the dysbiosis in supragingival plaque communities that initiates the clinical manifestations of ECC. The aim of this study was to determine the assembly of the oral microbiome during the first four years of life and compare it with the clinical development of ECC. The oral microbiomes of 134 children enrolled in a birth cohort study were determined at six ages between two months and four years-of-age and their mother's oral microbiome was determined at a single time point. We identified and quantified 356 operational taxonomic units (OTUs) of bacteria in saliva by sequencing the V4 region of the bacterial 16S RNA genes. Bacterial alpha diversity increased from a mean of 31 OTUs in the saliva of infants at 1.9 months-of-age to 84 OTUs at 39 months-of-age. The oral microbiome showed a distinct shift in composition as the children matured. The microbiome data were compared with the clinical development of ECC in the cohort at 39, 48, and 60 months-of-age as determined by ICDAS-II assessment. Streptococcus mutans was the most discriminatory oral bacterial species between health and current disease, with an increased abundance in disease. Overall our study demonstrates an ordered temporal development of the oral microbiome, describes a limited core oral microbiome and indicates that saliva testing of infants may help predict ECC risk.

Non-invasive screening of a microRNA-based dysregulation signature in oral cancer and oral potentially malignant disorders.

INTRODUCTION: We have previously shown that oral swirls are a robust source of microRNA protected by extracellular vesicles, potentially useful to detect oral squamous cell carcinoma (OSCC)-associated molecular aberration. OBJECTIVES: To study a developed dysregulation score and risk classification algorithm based upon a panel of OSCC-associated microRNA in oral swirls from individuals with OSCC and oral potentially malignant disorders (OPMDs). MATERIALS AND METHODS: An OSCC-associated panel of 5 microRNAs (miR-24; miR-21; miR-99a; let-7c; miR-100;) was quantified by qPCR in 190 individuals with and without mucosal abnormalities, including OSCC (n = 53) and OPMDs (n = 74). Each sample was analyzed using a developed dysregulation score (dSCORE) and risk classification algorithm, allocating a LOW- or HIGH-RISK score. The influence of demographic, systemic, oral health and mucosal disease factors on the developed test was analyzed. RESULTS: MicroRNA for analysis can be predictably isolated from oral swirls sourced from individuals with a range of demographic, systemic and oral health findings. Utilizing the presence of HIGH-RISK identified OSCC patients with 86.8% sensitivity and 81.5% specificity. Older age and female gender were associated with higher dSCOREs and higher proportions of HIGH-RISK classification amongst individuals with no mucosal abnormalities. The dSCOREs for all subgroups of OPMDs were significantly different from the OSCC group. CONCLUSION: This is the first comparison of microRNA sourced from oral swirls from individuals with OPMDs with individuals with and without OSCC. A HIGH-RISK dysregulation signature was found to be accurate in indicating the presence of OSCC and exampled to parallel malignant transformation.

CPP-ACP Promotes SnF2 Efficacy in a Polymicrobial Caries Model.

Dental caries is associated with plaque dysbiosis, leading to an increase in the proportions of acidogenic and aciduric bacteria at the expense of alkali-generating commensal species. Stannous fluoride (SnF2) slows the progression of caries by remineralization of early lesions but has also been suggested to inhibit glycolysis of aciduric bacteria. Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) promotes fluoride remineralization by acting as a salivary biomimetic that releases bioavailable calcium and phosphate ions, and the peptide complex has also been suggested to modify plaque composition. We developed a polymicrobial biofilm model of caries using 6 bacterial species representative of supragingival plaque that were cultured on sound human enamel and pulsed with sucrose 4 times a day to produce a high cariogenic challenge. We used this model to explore the mechanisms of action of SnF2 and CPP-ACP. Bacterial species in the biofilms were enumerated with 16S rRNA gene sequence analyses, and mineral loss and lesion formation were determined in the enamel directly under the polymicrobial biofilms via transverse microradiography. The model tested the twice-daily addition of SnF2, CPP-ACP, or both. SnF2 treatment reduced demineralization by 50% and had a slight effect on the composition of the polymicrobial biofilm. CPP-ACP treatment caused a similar inhibition of enamel demineralization (50%), a decrease in Actinomyces naeslundii and Lactobacillus casei abundance, and an increase in Streptococcus sanguinis and Fusobacterium nucleatum abundance in the polymicrobial biofilm. A combination of SnF2 and CPP-ACP resulted in a greater suppression of the acidogenic and aciduric bacteria and a significant 72% inhibition of enamel demineralization.

Anticariogenic efficacy of a saliva biomimetic in head-and-neck cancer patients undergoing radiotherapy.

BACKGROUND: The aim of this study was to investigate the effect of treatment with the saliva biomimetic, casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and SnF2 /NaF compared with SnF2 /NaF alone on coronal surface caries progression in head-and-neck cancer patients undergoing radiotherapy. METHODS: Twenty-four participants were randomized into two groups. Both groups used 0.4% SnF2 gel and a 0.32% NaF toothpaste; the test group also applied a crème containing 10% CPP-ACP three times daily while the control group used an identical crème without CPP-ACP (placebo). Resting saliva flow rate and saliva fluoride concentrations were determined. Caries status was assessed using ICDASII at baseline and 12-weeks postradiotherapy. Data were statistically analysed using a linear mixed effects model. RESULTS: Both groups showed significantly reduced resting saliva flow rate (P < 0.001) postradiotherapy. There were no significant differences in flow rates and fluoride concentration between groups. The CPP-ACP group exhibited a significant (P < 0.05) 51% reduction in coronal surface caries progression compared with the placebo group. CONCLUSION: Resting salivary flow rate was significantly reduced in head-and-neck cancer patients following radiotherapy and use of CPP-ACP with SnF2 /NaF significantly lowered caries progression compared with SnF2 /NaF alone.

Xerostomia, salivary characteristics and gland volumes following intensity-modulated radiotherapy for nasopharyngeal carcinoma: a two-year follow up.

BACKGROUND: To evaluate changes in xerostomia status, salivary characteristics and gland volumes 2 years following radiotherapy in nasopharyngeal carcinoma patients. METHODS: Xerostomia scores, salivary flow rates, pH and buffering capacity were measured at pre-radiotherapy, mid-radiotherapy, 2 weeks, 3 months and 2 years post-radiotherapy. Salivary gland volumes and their correlation with radiation dose were also assessed. RESULTS: Mean radiation dose to oral cavity, parotid and submandibular glands (SMG) was 44.5, 65.0 and 38.6 Gy respectively. Parotid and SMG volumes decreased 33% at 3 months post-radiotherapy; volumes at 2 years post-radiotherapy were 84% and 51% of pre-radiotherapy levels, respectively. Correlations were observed between parotid gland volume per cent reduction and its radiation dose and between resting salivary flow rate reduction and post-radiotherapy/pre-radiotherapy SMG volume ratio. Salivary flow rates and resting saliva pH remained significantly low at 2 years post-radiotherapy (both flow rates, P = 0.001; resting saliva pH, P = 0.005). Similarly, xerostomia scores remained significantly higher compared with pre-radiotherapy levels. CONCLUSIONS: Submandibular gland volumetric shrinkage persisted 2 years after radiotherapy. Xerostomia scores remained significantly higher, and salivary flow rates and resting saliva pH remained significantly lower, suggesting that study participants were still at risk for hyposalivation-related oral diseases.

Allbutt of Leeds and Duchenne de Boulogne: Newly discovered insights on Duchenne by a British neuropsychiatrist.

It is well-established that Guillaume-Benjamin-Amand Duchenne de Boulogne (1806-1875), and Jean-Martin Charcot (1825-1893) were the founding fathers of Parisian and French neurology during the second half of the 19th century, although much more is known about Charcot than about his "master" Duchenne. In Britain, Thomas Clifford Allbutt (1836-1925) was Leeds' most distinguished physician of the 19th century, eventually becoming Regius Professor of Physic at Cambridge. Allbutt's 1860-1861 year of postgraduate study in Paris and his friendship with Duchenne profoundly influenced his own contributions to nervous system and mental diseases, partly in collaboration with his colleague James Crichton-Browne (1840-1938) at the nearby West Riding Lunatic Asylum in Wakefield, Yorkshire. The present report briefly recalls the careers of Duchenne and Allbutt, and also presents a unique account by Allbutt of Duchenne in action at the height of his powers, investigating and defining the previously uncharted field of neuromuscular diseases with the aid of his localized electrization techniques. This account is discussed in relation to: Duchenne's personality and pioneering neurological achievements; the origins of French neurology; and the development of Anglo-French neurological relationships during the 19th century. Interestingly, both Duchenne and Crichton-Browne separately made important and much-appreciated contributions to the third major book by Charles Darwin (1809-1882), The Expression of the Emotions in Man and Animals, published in 1872.