Optimal dynamic incentive scheduling for Hawk-Dove evolutionary games.

The Hawk-Dove evolutionary game offers a paradigm of the trade-offs associated with aggressive and passive behaviors. When two (or more) populations of players compete, their success or failure is measured by their frequency in the population, and the system is governed by the replicator dynamics. We develop a time-dependent optimal-adaptive control theory for this dynamical system in which the entries of the payoff matrix are dynamically altered to produce control schedules that minimize and maximize the aggressive population through a finite-time cycle. These schedules provide upper and lower bounds on the outcomes for all possible strategies since they represent two extremizers of the cost function. We then adaptively extend the optimal control schedules over multiple cycles to produce absolute maximizers and minimizers for the system.

Electric scooters: convenient transport or ED headache?

Electric scooters (e-scooters) provide a potentially attractive means of private transportation in the pandemic era, during which use of public transport is discouraged. E-scooter use has become widespread recently, and we have noticed a concomitant rise in related craniomaxillofacial injuries, often associated with alcohol consumption and lack of protective equipment. We present here the first-published UK data on electric scooter injuries which, in the post-lockdown period, included facial lacerations, mandibular and midface fractures, avulsed teeth, and cervical spine injury. We urge that forthcoming legislation make e-scooters subject to at least the same requirements in lighting, helmet wear, and sobriety as bicycles and that, in this way, their benefits can be enjoyed while reducing associated morbidity and mortality.

Patient understanding of commonly used oral medicine terminology.

Introduction Communication within the doctor-patient relationship is complex due to a variety of reasons; a patient's understanding may not correspond with the clinician's vocabulary, resulting in misunderstanding, anxiety and ill-informed decision making. We investigated the understanding of terminology commonly used in oral and maxillofacial surgery and oral medicine clinics.Methods We investigated patients' understanding using a questionnaire-based study in the out-patient setting. Age, gender, first language and highest educational level were recorded. The questionnaire included multiple choice questions regarding patients' understanding of words as well as asking patients to define certain terms. Vocabulary included 'ulcer', 'blister', 'cancer', 'malignant' and 'benign'.Results and conclusions Many patients have difficulty in understanding and explaining commonly used terminology. 'Blister' was the most commonly understood term, while 'benign' and 'lesion' were the least well understood. 'Tumour' was mistakenly thought of as synonymous with 'malignancy' by over a third of patients. Understanding was better among those for whom English was their first language. It is essential that all clinicians modify their language appropriately during consultations in order to deliver information in a comprehensive manner, to educate patients on their condition thus enabling informed decision making by patients.

Physiologically based pharmacokinetic modeling framework for quantitative prediction of an herb-drug interaction.

Herb-drug interaction predictions remain challenging. Physiologically based pharmacokinetic (PBPK) modeling was used to improve prediction accuracy of potential herb-drug interactions using the semipurified milk thistle preparation, silibinin, as an exemplar herbal product. Interactions between silibinin constituents and the probe substrates warfarin (CYP2C9) and midazolam (CYP3A) were simulated. A low silibinin dose (160 mg/day × 14 days) was predicted to increase midazolam area under the curve (AUC) by 1%, which was corroborated with external data; a higher dose (1,650 mg/day × 7 days) was predicted to increase midazolam and (S)-warfarin AUC by 5% and 4%, respectively. A proof-of-concept clinical study confirmed minimal interaction between high-dose silibinin and both midazolam and (S)-warfarin (9 and 13% increase in AUC, respectively). Unexpectedly, (R)-warfarin AUC decreased (by 15%), but this is unlikely to be clinically important. Application of this PBPK modeling framework to other herb-drug interactions could facilitate development of guidelines for quantitative prediction of clinically relevant interactions.CPT Pharmacometrics Syst. Pharmacol. (2014) 3, e107; doi:10.1038/psp.2013.69; advance online publication 26 March 2014.

Psoas:lumbar vertebra index: central sarcopenia independently predicts morbidity in elderly trauma patients.

INTRODUCTION: Central sarcopenia as a surrogate for frailty has recently been studied as a predictor of outcome in elderly medical patients, but less is known about how this metric relates to outcomes after trauma. We hypothesized that psoas:lumbar vertebral index (PLVI), a measure of central sarcopenia, is associated with increased morbidity and mortality in elderly trauma patients. METHODS: A query of our institutional trauma registry from 2005 to 2010 was performed. Data was collected prospectively for the Pennsylvania Trauma Outcomes Study (PTOS). INCLUSION CRITERIA: age >55 years, ISS >15, and ICU LOS >48 h. Using admission CT scans, psoas:vertebral index was computed as the ratio between the mean cross-sectional areas of the psoas muscles and the L4 vertebral body at the level of the L4 pedicles. The 50th percentile of the psoas:L4 vertebral index value was determined, and patients were grouped into high (>0.84) and low (≤0.83) categories based on their relation to the cohort median. Primary endpoints were mortality and morbidity (as a combined endpoint for PTOS-defined complications). Univariate logistic regression was used to test the association between patient factors and mortality. Factors found to be associated with mortality at p < 0.1 were entered into a multivariable model. RESULTS: A total of 180 patients met the study criteria. Median age was 74 years (IQR 63-82), median ISS was 24 (IQR 18-29). Patients were 58 % male and 66 % Caucasian. Mean PLVI was 0.86 (SD 0.25) and was higher in male patients than female patients (0.91 ± 0.26 vs. 0.77 ± 0.21, p < 0.001). PLVI was not associated with mortality in univariate or multivariable modeling. After controlling for comorbidities, ISS, and admission SBP, low PLVI was found to be strongly associated with morbidity (OR 4.91, 95 % CI 2.28-10.60). CONCLUSIONS: Psoas:lumbar vertebral index is independently and negatively associated with posttraumatic morbidity but not mortality in elderly, severely injured trauma patients. PLVI can be calculated quickly and easily and may help identify patients at increased risk of complications.

Prenatal diagnosis and management of a craniofacial glioma detected at 20 weeks' gestation. Case report and review of the literature.

Foetal imaging and anomaly detection is advancing at a rapid rate. As a result, detection of foetal craniofacial abnormalities is increasing. Ultrasound and magnetic resonance imaging are currently the imaging modalities most commonly used. The authors describe the detection of a nasal glioma at 20 weeks' gestation, subsequent prenatal monitoring and postnatal management with surgical excision at 2 months of age. The world literature regarding prenatal diagnosis and management of craniofacial malformations is discussed.

Lingual necrosis secondary to mucormycosis.

Mucormycosis is a rare fungal infection with a high mortality that affects immunocompromised patients. This is an unusual case of necrosis of the tongue in a patient with pulmonary mucormycosis, diabetes mellitus, and aplastic anaemia.

The two-week rule in colorectal cancer. Can it deliver its promise?

Despite recent advances in technology, a high percentage of patients with colorectal cancer present with disease that is already advanced, leading to an overall 5-year survival rate of 49.6% in men and 50.8% in women. In order to facilitate access to specialist cancer units, across specialities, the Department of Health formulated the NHS Cancer Plan in 2000 which consisted, in part, of the 'two-week rule' (TWR). The TWR was launched to ensure that all patients meeting specific referral criteria for suspected colorectal cancer were seen by a hospital specialist within 14 days of referral. The TWR referral system was set up with the intention of identifying 90% of patients with bowel cancer for prompt treatment. This study was conducted to investigate the difference in presentation between patients referred via the TWR pathway compared to those referred via an elective (non-TWR) route and to examine the impact of these referral routes on the time to treatment and clinical outcome.

A study of skin sensitivity to various allergens by skin prick test in patients of nasobronchial allergy.

OBJECTIVE: To study skin sensitivity to various allergens in patients of nasobronchial allergy. MATERIALS AND METHODS: 2880 skin prick tests with 60 allergens were performed in 48 patients of nasobronchial allergy. RESULTS: Most common offending allergens were insects (21.2%), followed by dusts (12.0%), pollens (7.8%), animal dander (3.1%), and fungi (1.3%). The common insect antigen were locust female (33.3%) followed by locust male (25%), grasshopper (20.8%), cricket (16.7%), cockroach female (16.7%) and cockroach male (14.6%). Common dust allergens were house dust, wheat dust, cotton mill and paper dust. Among pollens, Amaranthus spinosus, Argemone mexicana, Adhatoda vasica, Ailanthus and Cannabis were found to be common allergens. In animal danders common offending allergens were cow dander and dog dander. Among fungi Aspergillus fumigatus, Aspergillus flavus, Alternaria teneis and Fusarium sodani were common allergens. Patients of bronchial asthma had associated allergic rhinitis in 80% cases. CONCLUSION: Common allergens in patients of nasobronchial allergy were identified. The data may prove useful in of allergen avoidance and immunotherapy in these patients.

Rhabdoid meningioma with cranial nerve involvement: case report of a child.

CASE REPORT: A 13-year-old girl presented with off and on headache for 1 year, hearing loss for 6 months and difficulty in closing eyes for 5 months along with mild cerebellar signs. Histopathologic evaluation of the tumor showed a rhabdoid meningioma (WHO Grade III). DISCUSSION: Rhabdoid meningiomas are uncommon in children, and only 4 cases have been reported so far. None of them presented with cranial nerve involvement. This unusual presentation is reported here. CONCLUSION: Though rare, rhabdoid meningiomas can occur in children. This, to the best of the authors' knowledge, is the first case of rhabdoid meningioma presenting with cranial nerve involvement.

Tension pneumoventricle following exposure of shunt chamber.

Pneumocephalus is the presence of air within the intracranial vault. Intraventricular pneumocephalus, also known as pneumoventricle is relatively rare and commonly occurs following cerebrospinal fluid diversion procedures. This may occur immediately or be delayed. Although a small amount of pneumoventriculus is asymptomatic and may not require any treatment, when present under tension it needs to be evacuated. We present a case of tension pneumoventricle following exposure of the shunt chamber, which resulted in deterioration of the patients' neurological condition and required evacuation.

Extruded Filshie clip presenting as an ischiorectal abscess.

This report adds to the small, but significant, literature base describing late complications following laparoscopic sterilisation. In women with recalcitrant peri-anal sepsis (who have previously undergone a sterilisation procedure) the possibility of tubal clip migration should be borne in mind. This is also an important learning point from a medicolegal point of view as patients presenting with the sequelae of clip migration will need to be counselled, and possibly investigated, with respect to the efficacy of their sterilisation procedure.

A comparative proteinomic analysis of nipple aspiration fluid from healthy women and women with breast cancer.

This pilot study examines the feasibility of nipple aspiration to distinguish women with breast cancer from healthy women using surface-enhanced laser desorption ionisation time-of-flight mass spectrometry (SELDI-TOF/MS). Nipple aspiration fluid (NAF) was collected from each breast in 21 women newly diagnosed with unilateral breast cancer and 44 healthy women. No differences were found when proteomic profiles of NAF from the cancer-bearing breast and the contralateral non-cancerous breast were compared. In contrast, 9 protein peaks were significantly different between the cancer-bearing breast compared with healthy women and 10 peaks were significantly different between the contralateral healthy breast and healthy women (P<0.05). These data suggest that invasive breast cancer may result in a field change across both breasts and that proteomic profiling of NAF may have more value in breast cancer risk assessment than as a diagnostic or screening tool.

Impact of HIV and AIDS on surgical practice.

INTRODUCTION: Surgical intervention has become a common component in the management of patients infected with the human immunodeficiency virus (HIV) or suffering from the clinical consequences of acquired immunodeficiency syndrome (AIDS). We investigated the evolution of this involvement at a tertiary referral centre for this condition over a 16-year period. PATIENTS AND METHODS: Detailed retrospective examination of the medical records of HIV-positive patients treated at the Royal Free Hospital between 1986 and 2002 was undertaken. Clinical, pathological and operative details of those patients who underwent surgical intervention were recorded. RESULTS: Of the 2100 cases reviewed, 477 patients underwent a combined total of 772 surgical procedures. Of the 772 operations, 95 (12.3%) were performed as emergencies. Anorectal surgery represented the highest group with a total of 195 procedures (25.26%) being undertaken. The majority of patients (59%) had AIDS at the time of surgery, and 27.04% had a significant co-existing medical problem. Overall postoperative complication rate was 10.1%, with the risk being significantly greater in those undergoing intra-abdominal surgery and emergency procedures. CONCLUSIONS: This is the largest study to audit the impact of HIV/AIDS in general surgical practice in the UK retrospectively. Surgery for HIV patients can be safely conducted with a low complication rate for the diagnostic and anorectal procedures that comprise the vast majority of surgery in HIV/AIDS patients. Medical treatment for patients with HIV/AIDS has developed dramatically over the last two decades. In parallel, this has resulted in a heavy, new and varied workload for general surgeons, who have also had to adapt in order to deal with the challenging spectrum of this disease.

Proteomic analysis of nipple aspirate fluid throughout the menstrual cycle in healthy pre-menopausal women.

A proteomic approach to nipple aspiration fluid (NAF) has been used in a number of studies comparing women with breast cancer and healthy women. However, to make useful comparisons between women with breast cancer and healthy women it is necessary to establish whether there is physiological variation in the proteomic profiles of NAF. The purpose of this study was, for the first time, to examine how the proteomic profile of NAF using surface-enhanced laser desorption ionisation time-of-flight mass spectrometry varies across the menstrual cycle in healthy pre-menopausal women. Twelve women were recruited and nipple aspiration was carried out weekly from both breasts of each subject for two menstrual cycles. Matching serum samples for luteinising hormone, follicle stimulating hormone and oestradiol were obtained at each aspiration attempt. Statistically significant peaks were found for three healthy volunteers (p < 0.05). However, the peaks that varied across the menstrual cycle were different from one healthy volunteer to another and the differences were small compared with the large variation in proteomic profiles between healthy volunteers. This study provides proof of concept that the NAF proteomic profile does not vary substantially during the menstrual cycle and that therefore it is valid to compare NAF profiles from pre-menopausal women that have been taken at different stages in the menstrual cycle.

The influence of radiotherapy on capsule formation and aesthetic outcome after immediate breast reconstruction using biodimensional anatomical expander implants.

BACKGROUND: Capsular contracture occurs more frequently when immediate breast reconstruction (IBR) is associated with radiotherapy (RT) in a post-mastectomy field. The aim of this study was to investigate the impact of RT on surgical outcome after IBR using a single implant type. METHODS: One hundred and thirty-six breast reconstructions were studied in 114 patients: 62 reconstructions were performed using submuscular implants alone and 74 had an implant-assisted latissimus dorsi myocutaneous flap using a McGhan 150 biodimensional permanent expander implant. Data were prospectively collected on capsule contracture, geometric measurements, photographic assessments and pain scores. The median follow-up was 4 (range, 2-5) years. RESULTS: The mean age of the 114 patients studied was 45 (range, 20-77) years. Forty-four reconstructed breasts received RT. Capsule formation was detected in 13/92 (14.1%) reconstructed breasts with no RT and in 17/44 (38.6%) reconstructed breasts with RT. On univariate analysis, RT was the only variable related to capsule formation (p<0.001). Significant differences in geometric measurements of symmetry were identified in patients with capsules compared with those without capsules. Photographic assessments were worse in the capsule group: mean photo score 8 (95% CI 8, 8.5) compared with the no capsule group 6.5 (95% CI 5, 7.5), p<0.001. Persistent pain two years or more after surgery was present in 8/30 patients with capsules and 1/106 with no capsule group, p<0.01. Capsule formation is three times more likely to occur after IBR in association with an RT field. However, as more than 60% of patients do not get capsules despite RT at four years, implant-assisted tissue expansion techniques using a biodimensional device is a viable breast reconstructive option in selected cases.

The intraductal approach to breast cancer biomarker discovery.

Established methods of breast cancer detection have well-described limitations, and new diagnostic techniques are evolving continually to improve diagnostic accuracy. The intraductal approach encompasses the modalities of nipple aspiration, ductal lavage, and duct endoscopy, and is a means of directly accessing the microenvironment of the breast and either sampling or visualizing this intraductal milieu. The aim of sampling this mammary microenvironment is to obtain samples from the physical surroundings of cells that are undergoing malignant transformation, thereby providing a new method of detection before the development of a clinically or radiologically discernible mass. A literature review was conducted to investigate the evolution of the intraductal approach and its particular application in the field of biomarker discovery, primarily using the intraductal technique of nipple aspiration, in combination with emerging protein profiling techniques.