Unveiling the Enhancement of Spontaneous Emission at Exceptional Points.

Exceptional points (EPs), singularities of non-Hermitian physics where complex spectral resonances degenerate, are one of the most exotic features of nonequilibrium open systems with unique properties. For instance, the emission rate of quantum emitters placed near resonators with EPs is enhanced (compared to the free-space emission rate) by a factor that scales quadratically with the resonance quality factor. Here, we verify the theory of spontaneous emission at EPs by measuring photoluminescence from photonic-crystal slabs that are embedded with a high-quantum-yield active material. While our experimental results verify the theoretically predicted enhancement, they also highlight the practical limitations on the enhancement due to material loss. Our designed structures can be used in applications that require enhanced and controlled emission, such as quantum sensing and imaging.

Surgical interventions in adult upper limb spasticity management: a systematic review.

Upper limb spasticity following upper motor neuron lesion is a key cause of long-term disability in adults, causing functional loss, pain, and reduced quality of life. Surgical management is an under-utilized intervention, and little work has been performed to collate and evaluate the evidence for these interventions. We undertake the first, PRISMA-compliant systematic review synthesizing the evidence for surgical management of spasticity in adults. Three databases were searched using pre-specified search strings over a 20-year window (September 2001-2021). Only primary research papers featuring an entirely adult sample were included. Case reports were excluded. Quality assessment was performed using the Oxford Centre for Evidence-Based Medicine Scale and the Methodological Index for Non-Randomized Studies. We identified 19 eligible studies, all of which were poor quality. Significant benefit of surgery was identified in 15 of the 16 studies conducting significance testing. Detailed analysis of the surgical procedures used was prevented by poor reporting. Studies reported low rates of serious postoperative complication, and relatively high rates of postoperative deformity recurrence. Studies' approaches to patient assessment and management varied significantly, reflecting a lack of standardization in this field. This review suggests that higher-quality, more standardized evidence is required to demonstrate the safety and efficacy of these surgical procedures. Future work should focus on improved reporting of surgical procedures and development of consensus assessment tools focusing on assessment of patient functionality and quality of life.

Recruitment of patients into head and neck clinical trials: acceptability of studies to patients from perspective of the research team.

We reviewed longitudinal recruitment data to assess recruitment into head and neck cancer trials, and to identify factors that could influence this and affect their acceptability to patients. We retrieved data from the prospective computerised database (2009-2016) to measure acceptability to patients using the recruitment:screening ratio, and compared observational with interventional studies, single specialty (or site) with multispecialty (or site) studies, and "step-up" randomisation with "non-inferiority" randomisation designs. A total of 1283 patients were screened and 583 recruited. The recruitment:screening ratio for all National Institute for Health Research (NIHR) portfolio studies combined was 0.47 (486/1133). Studies that involved treatment by several specialties or at several sites had a significantly adverse impact on acceptability (p=0.01). Recruitment into non-inferiority randomised controlled studies was lower than that into step-up randomised studies (p=0.06). The complexity of a study's design did not compromise recruitment. Treatment across several specialties or several sites and perceived non-inferiority designs, reduced the acceptability of some trials.

Effects of gesture and target on 12- and 18-month-olds' joint visual attention to objects in front of or behind them.

Factors affecting joint visual attention in 12- and 18-month-olds were investigated. In Experiment 1 infants responded to 1 of 3 parental gestures: looking, looking and pointing, or looking, pointing, and verbalizing. Target objects were either identical to or distinctive from distractor objects. Targets were in front of or behind the infant to test G. E. Butterworth's (1991b) hypothesis that 12-month-olds do not follow gaze to objects behind them. Pointing elicited more episodes of joint visual attention than looking alone. Distinctive targets elicited more episodes of joint visual attention than identical targets. Although infants most reliably followed gestures to targets in front of them, even 12-month-olds followed gestures to targets behind them. In Experiment 2 parents were rotated so that the magnitude of their head turns to fixate front and back targets was equivalent. Infants looked more at front than at back targets, but there was also an effect of magnitude of head turn. Infants' relative neglect of back targets is partly due to the "size" of adult's gesture.

A simplified method of harvesting and dilating the radial artery achieves acceptable clinical outcomes.

BACKGROUND: The recent successful revival of the radial artery as a coronary-bypass conduit has been attributed to a minimally traumatic harvesting technique without diathermy, combined with long-term oral calcium antagonist therapy. We describe a simplified technique of harvesting the radial artery, which reduces procurement time and maintains conduit relaxation. METHODS: Radial arteries were harvested using diathermy and topical glyceryl trinitrate-verapamil dilator solution. Postoperatively, intravenous glyceryl trinitrate, but no calcium antagonist was used. The clinical results in the first 100 consecutive patients receiving radial artery grafts (RA group), procured using this technique, were compared with a group of 100 patients receiving saphenous vein conduits (SV group) immediately prior to the introduction of the radial artery at our institution. RESULTS: There were no demographic differences between the two groups, other than the SV group being slightly older. There was one intraoperative death in each group. There was no difference in the rate of peri-operative myocardial infarction or length of stay in the intensive care unit. At a median follow-up time of 16 months for the RA group, and 25 months for the SV group, the survival rates were 97 and 94%, respectively. All survivors were in the New York Heart Association class I. In the SV group, two postoperative angioplasties were performed. CONCLUSIONS: These early results suggest that this method of procuring the radial artery using diathermy, glyceryl trinitrate and no postoperative calcium antagonists, is rapid, safe and effective. The continued use of this technique is justified, while awaiting the results of long-term angiographic studies.

Outcomes of coronary artery bypass grafting: a 3 year analysis using the Society of Thoracic Surgeons Database.

BACKGROUND: Accurate risk factor analysis is a critical element in contemporary cardiac surgical practice. In the USA, the Society of Thoracic Surgeons Database allows institutions and individual surgeons to carry out detailed patient risk assessment and to review their cardiac surgical outcomes in a comparative fashion. METHODS: To evaluate outcomes of isolated coronary artery bypass grafting, data from all patients operated upon at the Alfred Hospital, Melbourne, Australia, over a 3 year period were entered into the Society of Thoracic Surgeons Database. RESULTS: Our results (mortality and morbidity) compared favourably with those contained within this large international database. CONCLUSION: It is hoped that a similar Australasian database can be established to facilitate a meaningful local risk assessment and a comparative analysis of outcomes of cardiac surgical procedures.

Pulmonary arteriovenous fistula: presentation, diagnosis, and treatment.

Pulmonary arteriovenous fistulas (PAVFs) are rare vascular malformations of the lung. There is a strong association with Rendu-Osler-Weber disease. Although most patients are asymptomatic, PAVFs can cause dyspnea from a right-to-left shunt. They can also bleed and result in hemoptysis and hemothorax. Because of paradoxical emboli, various central nervous system complications have been described including stroke, and brain abscess. Currently, spiral computed tomography offers the most practical method for establishing the presence of PAVFs. Most patients should be treated. Therapeutic options include angiographic embolization with metal coils or balloon occlusion and surgical excision. Angiographic treatment has become the mainstay of therapy for most patients during the last decade. It is less invasive and can be repeated easily. Surgery, which usually consists of a conservative lung resection, is associated with low morbidity and a low recurrence rate. Both therapeutic approaches are discussed. The Mayo Clinic surgical experience of the last 20 years for PAVFs is presented.

Increased beta-cell proliferation and reduced mass before diabetes onset in the nonobese diabetic mouse.

To determine whether loss of beta-cell mass and function in the NOD mouse occurs gradually, beginning after the onset of insulitis, or abruptly, just before the onset of overt diabetes, beta-cell mass and rates of beta-cell proliferation and insulin secretory responses from the perfused pancreas were measured in NOD and control NOD/Scid mice at 8-9, 13, and 18 weeks of age. Of the NOD mice, 11 and 70% had diabetes (fasting blood glucose >8.3 mmol/l) at 13 and 18 weeks of age, respectively. Beta-cell mass in 8-week-old NOD mice was 69% of control mice (P>0.05), but the rate of 5-bromo-2-deoxyuridine uptake was greater, suggesting a compensatory proliferative response to ongoing autoimmune beta-cell destruction. Despite an increase in the rate of beta-cell proliferation, beta-cell mass was significantly reduced by 42% in 13-week-old nondiabetic NOD mice and by 73% in 18-week-old diabetic NOD mice. Insulin secretory responses to glucose and arginine demonstrated reductions of similar magnitude. In 18-week-old diabetic NOD mice, insulin secretion was reduced to a greater degree than beta-cell mass, suggesting the presence of beta-cell dysfunction in addition to reduced mass. These results suggest that in the NOD mouse, beta-cell destruction begins soon after the onset of insulitis. Despite a compensatory beta-cell proliferative response, beta-cell mass progressively falls and is significantly reduced by 13 weeks despite normal blood glucose concentrations. Diabetes may be present when residual beta-cell mass represents 30% of control levels.

Infants' perception of dynamic affective expressions: do infants distinguish specific expressions?

Seven-month-old infants' perception of positive (happy, interested) and negative (angry, sad) affective expressions was investigated using a preferential looking procedure (n = 20 in each of 6 conditions). The infants saw two videotaped facial expressions and heard a single vocal expression concordant with one of the facial expressions. The voice on the soundtrack was played 5 s out of synchrony with the ongoing affective visual display. Infants participated in one of six conditions (all possible pairs of the four expressive events). Infants' visual fixations to the affectively concordant and affectively discordant displays were recorded. Infants looked longer at the affectively concordant displays than at the affectively discordant displays in all conditions except the happy/sad and interested/sad conditions. For these two comparisons, facial discrimination was demonstrated by the infants' preferential looking at happy and interested expressions compared to the sad expression. Thus, 7-month-old infants discriminate among happy, interested, angry, and sad expressions, demonstrating differentiation among specific, dynamic expressions. The results are discussed in terms of the information specifying facial and vocal affect and the possible role of familiarity in learning to differentiate among affective expressions during infancy.

Effect of sternotomy direction on the incidence of inadvertent pleurotomy.

OBJECTIVE: Median sternotomy was performed by 2 different techniques in order to determine whether there was a difference in the incidence of inadvertent pleural entry. EXPERIMENTAL DESIGN: Patients were prospectively evaluated and reviewed at a mean follow-up interval of 8.2 months. PATIENTS AND METHODS: Ninety five consecutive patients underwent primary sternotomy at a single tertiary referral center. MEASURES: Planned outcome measures included, incidence of pleural entry, length of hospitalization, and chest tube site related postoperative morbidity. RESULTS: Group 1 (n=49) had sternotomy undertaken from the sternal notch proceeding downwards. Group 2 (n=46) underwent sternotomy performed from the xiphoid upwards. Mediastinal evaluation revealed a significant reduction in the incidence of pleural violation for group 1 (3) versus group 2 (11) (p=0.014). This difference was not found to be surgeon specific. CONCLUSIONS: Sternotomy undertaken from the sternal notch proceeding downwards is shown to be associated with a reduced incidence of inadvertent pleural entry. Potential advantages for this approach also include reduced respiratory morbidity, less chest tube site complications and a trend to reduced length of hospitalization.

Defective insulin secretion in hepatocyte nuclear factor 1alpha-deficient mice.

Mutations in the gene for the transcription factor hepatocyte nuclear factor (HNF) 1alpha cause maturity-onset diabetes of the young (MODY) 3, a form of diabetes that results from defects in insulin secretion. Since the nature of these defects has not been defined, we compared insulin secretory function in heterozygous [HNF-1alpha (+/-)] or homozygous [HNF-1alpha (-/-)] mice with null mutations in the HNF-1alpha gene with their wild-type littermates [HNF-1alpha (+/+)]. Blood glucose concentrations were similar in HNF-1alpha (+/+) and (+/-) mice (7.8+/-0.2 and 7.9+/-0.3 mM), but were significantly higher in the HNF-1alpha (-/-) mice (13.1+/-0.7 mM, P < 0.001). Insulin secretory responses to glucose and arginine in the perfused pancreas and perifused islets from HNF-1alpha (-/-) mice were < 15% of the values in the other two groups and were associated with similar reductions in intracellular Ca2+ responses. These defects were not due to a decrease in glucokinase or insulin gene transcription. beta cell mass adjusted for body weight was not reduced in the (-/-) animals, although pancreatic insulin content adjusted for pancreas weight was slightly lower (0.06+/-0.01 vs. 0.10+/-0.01 microg/mg, P < 0.01) than in the (+/+) animals. In summary, a null mutation in the HNF-1alpha gene in homozygous mice leads to diabetes due to alterations in the pathways that regulate beta cell responses to secretagogues including glucose and arginine. These results provide further evidence in support of a key role for HNF-1alpha in the maintenance of normal beta cell function.

Role of apoptosis in failure of beta-cell mass compensation for insulin resistance and beta-cell defects in the male Zucker diabetic fatty rat.

To define the mechanisms involved in the evolution of diabetes in the Zucker diabetic fatty (ZDF) rat, beta-cell mass and replication rates were determined by immunochemistry, point-counting morphometry, and 6-h 5-bromo-2'-deoxyuridine (BrdU) incorporation. The beta-cell mass in 5- to 7-week-old prediabetic ZDF rats (4.3 +/- 0.06 mg) was similar to age-matched insulin-resistant Zucker fatty (ZF) rats (3.7 +/- 0.05 mg) and greater than that in Zucker lean control (ZLC) rats (1.9 +/- 0.3, P < 0.05). At 12 weeks (after diabetes onset), beta-cell mass in the ZDF rats (8.1 +/- 1.7 mg) was significantly lower than the ZF rats (15.7 +/- 1.8 mg). The mass in the ZF rats was significantly greater than in the ZLC rats (4.3 +/- 0.8 mg, P < 0.05). The beta-cell proliferation rate (mean of both time points) was significantly greater in the ZDF rats (0.88 +/- 0.1%) compared with the ZF and ZLC rats (0.53 +/- 0.07%, 0.62 +/- 0.07%, respectively, P < 0.05), yet ZDF rats have a lower beta-cell mass than the ZF rats despite a higher proliferative rate. Morphological evidence of neogenesis and apoptosis is evident in the ZF and ZDF rats. In addition, even at 5-7 weeks a modest defect in insulin secretion per beta-cell unit was found by pancreas perfusion. These studies provide evidence that the expansion of beta-cell mass in response to insulin resistance and insulin secretory defects in diabetic ZDF rats is inadequate. This failure of beta-cell mass expansion in the ZDF rat does not appear to be from a reduction in the rate of beta-cell proliferation or neogenesis, suggesting an increased rate of cell death by apoptosis.

Third and fourth operations for myocardial ischemia: short-term results and long-term survival.

BACKGROUND: An increasing number of patients having at least two operations for myocardial ischemia are now presenting for a third or fourth procedure. We report the Mayo Clinic experience with repeated reoperative surgery for coronary artery disease. METHODS AND RESULTS: We have evaluated 67 consecutive patients (54 men, 13 women) during a 14-year period (1978 to 1992). The mean age at the third procedure (n=63) was 63.4 years and at the fourth procedure (n=4) was 70.6 years. Clinical indications for surgery were unstable angina in 29 patients (43%), New York Heart Association class III angina in 36 (54%), non-Q wave acute myocardial infarction in 1, and acute pulmonary edema in 1. Urgent or emergency surgery was undertaken in 17 patients (25%). All patients had triple-vessel disease, and 20 (30%) had left main coronary artery stenosis >50%. The mean ejection fraction in 56 patients was 0.56+/-0.11. Occlusion or significant stenoses of preexisting saphenous grafts were thought to be the major cause of recurrent ischemia in 64 patients (96%). Only 14 patients (21%) had received previous arterial grafts. An average of 2.4 grafts was placed, and a new internal mammary artery was used on 47 occasions. Eight patients (11.9%) died. Three patients required a left ventricular assist device, and one of them survived. There were 21 late deaths: 8 were cardiac and 5 were likely to be cardiac. Five-year and 10-year survival in all patients was 75.6%+/-5.3% and 47.9%+/-7.7%, respectively. Freedom from further intervention for hospital survivors at 5 and 10 years was 88.4+/-4.5 and 72.3+/-8.5%, respectively. Of the 38 patients still alive at last follow-up, 29 (76%) were considered to be in New York Heart Association functional class I or II. On univariate analysis, use of an intra-aortic balloon pump, prolonged bypass time, left main coronary artery stenosis >50%, and a surgeon's impression of angiographic inoperability correlated with increased risk of early mortality. CONCLUSION: We conclude that in a select group of patients, repeated reoperative surgery, despite an increased mortality, can result in good long-term survival and significant improvement in clinical status.

Single versus bilateral internal mammary artery grafts: 10-year outcome analysis.

BACKGROUND: The superior long-term patency of the internal mammary artery (IMA) confers important short-term and late survival advantages when grafted to the left anterior descending coronary artery. However, it remains uncertain whether patients derive additional survival benefit when both IMAs are used in coronary revascularization. METHODS: Between June 1983 and May 1986, 160 patients (mean age 60 years) received bilateral IMA grafts for coronary artery bypass procedures, and in 93% of patients, the right IMA was used to bypass the left coronary system. During a similar interval, a group of 161 patients matched for symptomatic status and extent of disease (mean age, 62 years) received a single left IMA and saphenous vein grafts. RESULTS: The two groups were similar with respect to gender, preoperative angina class, priority status, extent of coronary artery disease, left ventricular function, and number of distal anastomoses. Diabetes was more prevalent in the patient group receiving a single IMA graft (27% versus 17.5%; p = 0.05). Early outcome was similar in the two groups; operative mortality was 0.6% for the patient group receiving single IMA grafts and 0% for those with bilateral IMA grafts. The mean follow-up of 320 hospital survivors was 10 years. Univariate analysis revealed significantly fewer overall deaths in the patients receiving bilateral IMA grafts (n = 30; p = 0.05), and less late cardiac mortality (n = 12; p = 0.016). Ten-year actuarial survival for patients dismissed from the hospital was 76% for those receiving single IMA graft versus 85% for those receiving bilateral IMA grafts. Multivariate analysis revealed diabetes (risk ratio = 1.73), advancing age (risk ratio = 1.08), and lower ejection fraction (risk ratio = 1.01) to be the only significant predictors of late cardiac death. Use of a single IMA graft was not significant (p = 0.138) despite a risk ratio of 1.78. Use of only a single IMA graft correlated with an increased risk of angina recurrence (p < 0.001), late myocardial infarction (p = 0.019), and risk of any cardiac event (p < 0.001). CONCLUSIONS: Independent risk factors for late death were diabetes mellitus, older age, and reduced ejection fraction. Patients receiving bilateral IMA grafts had better long-term survival than those with a single IMA graft, but this was not independent of diabetes. Multivariate analysis, however, did confirm that compared with single arterial grafts, bilateral IMA grafting was an independent predictor of lower rates of angina recurrence, late myocardial infarction, and the composite end point of any cardiac event.

Podocarpus gracilior and Callitris verrucosa--newly identified allergens that crossreact with Cupressus sempervirens.

Thirty-six symptomatic patients, with positive skin reactions to Cupressus sempervirens pollen extract were skin-tested with pollen extracts of Podocarpus gracilior and Callitris verrucosa, of these 17 (47%) had positive responses to P. gracilior, nine (25%) to C. verrucosa, and six (17%) to both. None of the non-atopic healthy controls had positive reactions to either of the extracts. Radioallergosorbent test (RAST)-inhibition studies were performed with pooled sera from three patients. Fifty per cent inhibition was obtained with 11 micrograms protein of C. sempervirens, 54 micrograms of P. gracilior, and 71 micrograms of C. verrucosa; however, when pollen extract of Olea europaea, an unrelated allergen, was tested, 265 micrograms protein were needed to obtain 50% inhibition. One-dimension sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of pollen extracts from the three species revealed that they had several very similar protein bands. Using Western blot analysis, several closely related IgE binding proteins were identified in the three species. It was concluded that the pollen grains of P. gracilior and of C. verrucosa are potentially allergenic. The presence of common allergenic proteins indicate partial crossreactivity with C. sempervirens.

Relationship between immunoglobulin levels and extremes of solar activity.

The possible relationship between epidemics and extremes of solar activity has been discussed previously. The purpose of the present study was to verify whether differences in the levels of immunoglobulins (IgA, IgG, IgM) could be noted at the highest (July 1989) and lowest (September 1986) points of the last (21st) and present (22nd) 11-year solar cycle. The work was divided into a 1-month study (covering the month of minimal or maximal solar activity), a 3-month study (1 month before and after the month of minimal or maximal solar activity) and a 5-month study (2 months before and after the month of minimal or maximal solar activity). A trend of a drop-off for all three immunoglobulins was seen on the far side of the maximal point of the solar cycle. Statistical significance was achieved in the 5-month study for IgM (P = 0.04), and a strong trend was shown for IgG (P = 0.07). Differences between the sexes were also noted.

Serum IgE concentrations, disease activity, and atopic disorders in systemic lupus erythematosus.

We investigated the relationship between disease activity and total IgE concentration in the sera of patients with active systemic lupus erythematosus (SLE). In addition, the prevalence of personal and family history of allergic rhinitis and asthma were examined with a questionnaire and immediate skin tests for common inhalant allergens in 24 patients in remission. In the 20 patients with active disease, we found that IgE concentration was significantly higher during the periods of active disease than the periods of remission. This elevation was not associated with an elevation in total serum IgG concentrations. The increase in IgE concentration during disease activity in patients with active nephritis was significantly higher than in patients without nephritis. Of the 24 patients in remission, only one reported allergic rhinitis, and two had positive skin tests for inhalant allergens. We concluded that, although patients with SLE do not have an increased rate of atopic disorders, serum IgE rises during disease activity and is associated with active nephritis. This phenomenon suggests that IgE may be involved in the pathogenesis of SLE, particularly in patients with nephritis.

Is granulocyte-macrophage colony-stimulating factor (GM-CSF) safe in myelodysplastic syndromes?

The complication of secondary myelodysplastic syndrome (sMDS) during the course of multiple myeloma (MM) has been recognized for more than a decade. sMDS occurs years after MM diagnosis, and typically, at sMDS presentation the MM is stable or inactive. We report a 56-year-old patient, who developed sMDS 15 years following the diagnosis of IgG-lambda MM, which had been completely stable for 13 years. However, very soon after sMDS was diagnosed, the MM relapsed and required combination chemotherapy. The first cycle of vincristine, adriamycin and dexamethasone (VAD) resulted in severe neutropenia and sepsis, which was treated with antibiotics and recombinant human granulocyte-macrophage colony-stimulating factor (rHuGM-CSF). Two weeks after GM-CSF administration a transformation to acute myeloblastic leukemia was observed. The relation between GM-CSF and the leukemic transformation is discussed and the possible contribution of the cytokine to the stimulation of this complication is emphasized.

Secondary myelodysplastic syndrome in multiple myeloma--a study of nine patients with an attempt to detect myeloma patients at risk.

Over a follow-up period of ten years, nine of our 100 patients with multiple myeloma (MM), developed myelodysplastic syndrome (MDS, preleukaemia). MDS occurred 19-156 (median 35) months from the diagnosis of MM. Six patients presented with pancytopenia and no patients had active MM at the time of MDS diagnosis. Three patients were defined as having refractory anaemia (RA) and six as refractory anaemia with excess blasts (RAEB) or RAEB in transformation (RAEBT), according to the FAB classification. The clinical course is characterized by increasing red blood cell and platelet transfusion requirements, recurrent infections and bleeding episodes. All patients, except for one, died within 3 to 8 (median 5) months from MDS diagnosis. The causes of death were sepsis or bleeding; three patients underwent leukaemic transformation. Thus, the clinical course of this small group of myeloma patients who developed secondary MDS (sMDS), was similar to other series of patients with sMDS. Serial bone marrow examinations suggest an initial hypercellular phase, followed by a rapidly evolving preterminal hypocellular marrow. In an attempt to detect MM patients at risk of developing sMDS, the epidemiological (including ethnic), clinical and laboratory data of the 9 MDS patients at the time of the MM presentation were reviewed and compared to the other MM patients. No significant differences were observed between the two groups in most parameters, except for two. All MDS patients were Ashkenazi Jews and no patients of Sepharadic origin developed MDS. Also, no IgA-myeloma patient developed MDS. If these findings are confirmed in a larger series, it may point to subgroups at risk which may require a different approach.(ABSTRACT TRUNCATED AT 250 WORDS)