Nano-Magnesium Oxide: A Novel Bactericide Against Copper-Tolerant Xanthomonas perforans Causing Tomato Bacterial Spot.

Bacterial spot caused by Xanthomonas perforans causes significant damage on tomato in Florida. Due to the presence of copper (Cu)-tolerant X. perforans strains, Cu bactericides are not effective in disease management. Hence, there is a critical need to find alternatives for Cu. Antibacterial activity of magnesium oxide (Nano-MgO), and other metal oxide nanoparticles, were evaluated against a Cu-tolerant and -sensitive X. perforans strain. In vitro experiments demonstrated high antibacterial activity of Nano-MgO against both strains compared with the commercial Cu. The minimum inhibitory concentration of Nano-MgO is 25 µg/ml and the minimum bactericidal concentration is 100 µg/ml against a Cu-tolerant X. perforans strain after 4 h of exposure. Structural changes in the bacterial membrane following exposure to Nano-MgO treatments compared with the controls were observed using transmission electron microscopy. In two greenhouse experiments with a Cu-tolerant strain, bacterial spot severity was significantly reduced by Nano-MgO at 200 µg/ml compared with Cu-ethylene bis-dithiocarbamate (grower standard), and the untreated control (P = 0.05). In three field experiments, Nano-MgO at 200 µg/ml significantly reduced disease severity with no negative impact on yield compared with the untreated control. Inductively coupled plasma mass spectrometric analysis of the fruit confirmed that Nano-MgO application did not lead to the accumulation of Mg, Cu, Ca, K, Mn, P, and S. This study is the first to demonstrate the potential of Nano-MgO against bacterial spot of tomato.

The psychological burden of disease among patients undergoing cervical spine surgery: Are we underestimating our patients' inherent disability?

BACKGROUND: Studies have utilized psychological questionnaires to identify the psychological distress among certain surgical populations. RESEARCH QUESTION: Is there an additional psychological burden among patients undergoing surgical treatment for their symptomatic degenerative cervical disease? MATERIALS AND METHODS: Patients>18 years of age with symptomatic, degenerative cervical spine disease were included and prospectively enrolled. Correlations and multivariable logistic regression analysis assessed the relationship between these mental health components (PCS, FABQ) and the severity of disability described by the NDI, EQ-5D, and mJOA score. Patient distress scores were compared to previously published benchmarks for other diagnoses. RESULTS: 47 patients were enrolled (age: 56.0 years,BMI: 29.7kg/m2). Increasing neck disability and decreasing EQ-5D were correlated with greater PCS and FABQ(all P<0.001). Patients with severe psychological distress at baseline were more likely to report severe neck disability, while physician-reported mJOA had weaker associations. Compared to historical controls of lumbar patients, patients in our study had greater levels of psychological distress, as measured by FABQ (40.0 vs. 17.6; P<0.001) and PCS (27.4 vs. 19.3;P<0.001). DISCUSSION AND CONCLUSION: Degenerative cervical spine patients seeking surgery were found to have a significant level of psychological distress, with a large portion reporting severe fear avoidance beliefs and catastrophizing pain at baseline. Strong correlation was seen between patient-reported functional metrics, but less so with physician-reported signs and symptoms. Additionally, this population demonstrated higher psychological burden in certain respects than previously identified benchmarks of patients with other disorders. Preoperative treatment to help mitigate this distress, impact postoperative outcomes, and should be further investigated. LEVEL OF EVIDENCE: Level III.

Facial emotion recognition in adolescents with psychotic-like experiences: a school-based sample from the general population.

BACKGROUND: Psychotic symptoms, also termed psychotic-like experiences (PLEs) in the absence of psychotic disorder, are common in adolescents and are associated with increased risk of schizophrenia-spectrum illness in adulthood. At the same time, schizophrenia is associated with deficits in social cognition, with deficits particularly documented in facial emotion recognition (FER). However, little is known about the relationship between PLEs and FER abilities, with only one previous prospective study examining the association between these abilities in childhood and reported PLEs in adolescence. The current study was a cross-sectional investigation of the association between PLEs and FER in a sample of Irish adolescents. METHOD: The Adolescent Psychotic-Like Symptom Screener (APSS), a self-report measure of PLEs, and the Penn Emotion Recognition-40 Test (Penn ER-40), a measure of facial emotion recognition, were completed by 793 children aged 10-13 years. RESULTS: Children who reported PLEs performed significantly more poorly on FER (ß=-0.03, p=0.035). Recognition of sad faces was the major driver of effects, with children performing particularly poorly when identifying this expression (ß=-0.08, p=0.032). CONCLUSIONS: The current findings show that PLEs are associated with poorer FER. Further work is needed to elucidate causal relationships with implications for the design of future interventions for those at risk of developing psychosis.

Dengue virus identification by transmission electron microscopy and molecular methods in fatal dengue hemorrhagic fever.

Dengue virus is the most significant virus transmitted by arthropods worldwide and may cause a potentially fatal systemic disease named dengue hemorrhagic fever. In this work, dengue virus serotype 4 was detected in the tissues of one fatal dengue hemorrhagic fever case using electron immunomicroscopy and molecular methods. This is the first report of dengue virus polypeptides findings by electron immunomicroscopy in human samples. In addition, not-previously-documented virus-like particles visualized in spleen, hepatic, brain, and pulmonary tissues from a dengue case are discussed.

Comparing "intra operative" tissue engineering strategies for the repair of craniofacial bone defects.

BACKGROUND: In craniofacial reconstruction, the gold standard procedure for bone regeneration is the autologous bone graft (BG). However, this procedure requiring bone harvesting is a source of morbidity. Bone substitutes, such as biphasic calcium phosphate (BCP), represent an interesting alternative but are not sufficient for bone healing in hypoplastic conditions. In such conditions, osteoprogenitors are essential to provide osteoinduction. Previous studies have shown that BCP associated with total bone marrow (TBM) provides same bone reconstruction as bone graft in a rat model of calvaria defect. Furthermore, adipose tissue stromal vascular fraction (SVF) seems to be another promising source of osteoprogenitor cells that can be used intra-operatively. This study aimed to combine, intra-operative BCP-based bone tissue engineering strategies with TBM or SVF from human sources. METHODS: 5 mm critical-size calvaria defects were performed in 18 nude rat. The defects were filled with intra-operative bone tissue engineering procedures: human BG, human TBM + BCP, human SVF + BCP and, rat TBM + BCP. Animals were sacrificed 8 weeks after implantation and calvaria were processed for histological and radiological examinations. Implanted cells were labelled with a fluorochrome. RESULTS: Micro-CT analysis revealed partial repair of bone defect. Only hBG significantly succeeded in healing the defect (43.1%). However, low rate of newly formed bone tissue was observed in all tissue engineering conditions (hTBM, hSVF, ratTBM). DISCUSSION: The lack of bone formation observed in this study could possibly be attributed to the model. CONCLUSION: This study combined with a literature analysis show the stringency of the nude rat calvaria model in term of bone regeneration.

Particle-size dependent bactericidal activity of magnesium oxide against Xanthomonas perforans and bacterial spot of tomato.

Bacterial spot, caused by Xanthomonas spp., is a highly destructive disease of tomatoes worldwide. Copper (Cu) bactericides are often ineffective due to the presence of Cu-tolerant strains. Magnesium oxide (MgO) is an effective alternative to Cu bactericides against Xanthomonas spp. However, the effects of particle size on bactericidal activity and fruit elemental levels are unknown. In this study, nano (20 nm) and micron (0.3 and 0.6 µm) size MgO particles were compared for efficacy. Nano MgO had significantly greater in vitro bactericidal activity against Cu-tolerant X. perforans than micron MgO at 25-50 µg/ml. In field experiments nano and micron MgO applied at 200 and 1,000 µg/ml were evaluated for disease control. Nano MgO at 200 µg/ml was the only treatment that consistently reduced disease severity compared to the untreated control. Inductively Coupled Plasma Optical Emission Spectroscopy revealed that nano MgO applications did not significantly alter Mg, Cu, Ca, K, Mn, P and S accumulation compared to fruits from the untreated plots. We demonstrated that although both nano MgO and micron MgO had bactericidal activity against Cu-tolerant strains in vitro, only nano MgO was effective in bacterial spot disease management under field conditions.

Role and regulation of acylethanolamides in energy balance: focus on adipocytes and beta-cells.

The endocannabinoid, arachidonoylethanolamide (AEA), and the peroxisome proliferator-activated receptor (PPAR)-alpha ligand, oleylethanolamide (OEA) produce opposite effects on lipogenesis. The regulation of OEA and its anti-inflammatory congener, palmitoylethanolamide (PEA), in adipocytes and pancreatic beta-cells has not been investigated. We report here the results of studies on acylethanolamide regulation in these cells during obesity and hyperglycaemia, and provide an overview of acylethanolamide role in metabolic control. We analysed by liquid chromatography-mass spectrometry OEA and PEA levels in: 1) mouse 3T3F442A adipocytes during insulin-induced differentiation, 2) rat insulinoma RIN m5F beta-cells kept in 'low' or 'high' glucose, 3) adipose tissue and pancreas of mice with high fat diet-induced obesity (DIO), and 4) in visceral fat or blood of obese or type 2 diabetes (T2D) patients. In adipocytes, OEA levels remain unchanged during differentiation, whereas those of PEA decrease significantly, and are under the negative control of both leptin and PPAR-gamma. PEA is significantly downregulated in subcutaneous adipose tissue of DIO mice. In RIN m5F insulinoma beta-cells, OEA and PEA levels are inhibited by 'very high' glucose, this effect being enhanced by insulin, whereas in cells kept for 24 h in 'high' glucose, they are stimulated by both glucose and insulin. Elevated OEA and PEA levels are found in the blood of T2D patients. Reduced PEA levels in hypertrophic adipocytes might play a role in obesity-related pro-inflammatory states. In beta-cells and human blood, OEA and PEA are down- or up-regulated under conditions of transient or chronic hyperglycaemia, respectively.

Antibodies from patients with dengue viral infection mediate cellular cytotoxicity.

Acute and late convalescent sera (collected at day 5 of disease onset and 1 year later) from dengue fever (DF) and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) laboratory confirmed cases, were tested for antibody-dependent cell-mediated cytotoxicity (ADCC) activity using dengue 1 (DENV-1) or dengue 2 (DENV-2) infected cells as target. All patients experienced their first dengue virus (DENV) infection 20 years before. ADCC activity was detected in acute sera from DHF/DSS but not in sera from DF patients. However, 1 year after illness, ADCC activity was observed in all cases. This preliminary report represents one of the few studies of ADCC in dengue patients and suggests that ADCC could be implicated in dengue pathogenesis.

Phenotypic variation of carbohydrate surface antigens and the pathogenesis of Haemophilus influenzae infections.

Phenotypic variation of two major carbohydrate surface antigens of Haemophilus influenzae, the capsule and lipopolysaccharide, exemplifies some of the genetic mechanisms used by pathogenic bacteria in interacting with host microenvironments. The ability to generate phenotypic variety at high frequency within clonal populations of microorganisms provides an adaptive mechanism to combat the polymorphisms and immune repertoires of the host.

Event-related brain potentials reveal correlates of the transformation of stimulus functions through derived relations in healthy humans.

This research aimed to explore the neural correlates of relational learning by recording high-density EEG during a behavioural task involving derivation levels of varying complexity. A total of 15 participants (5 male; age range 18-23 years; mean age=20.0 years) completed contextual cue training, relational learning, function training and a derivation task while 128-channel event-related potentials (ERPs) were recorded from the scalp (Background). Differences in response latencies were observed between the two derived (symmetry and equivalence) and directly trained relations, with longest latencies found for equivalence and shortest for the directly trained relations. This pattern failed to reach statistical significance. Importantly, ERPs revealed an early P3a positivity (from 230 to 350ms) over right posterior scalp sites. Significantly larger mean amplitudes were found at three channels (P6, E115 and E121) for the equivalence relations compared to the two other types (Results). We believe this may constitute a first demonstration of differences in brain electrophysiology in the transformation of stimulus functions through derived relations of hierarchical levels of complexity (Conclusions).

Dynamical relativistic effects in quasielastic 1p-shell proton knockout from 16O

We have measured the cross section for quasielastic 1p-shell proton knockout in the 16O(e,e(')p) reaction at omega = 0.439 GeV and Q2 = 0.8 (GeV/c)(2) for missing momentum P(miss)

Comparative study of Schistosoma mansoni isolated from patients with hepatosplenic and intestinal clinical forms of schistosomiasis.

Six Schistosoma mansoni isolates obtained from the same endemic area were compared experimentally; three were from patients with the hepatosplenic form and three from patients with the intestinal form of schistosomiasis. The following features were analyzed in mice: body weight, liver and spleen weights, mortality, infectivity, number of S. mansoni eggs/female worm, egg distribution in the viscera, and hemogram. Three groups of mice, used as controls, were infected with the LE strain of S. mansoni which is routinely maintained in the laboratory. The group of isolates from patients with the hepatosplenic form of schistosomiasis did not show important differences in relation to those from nonhepatosplenic patients; in almost all features analyzed the differences among these six isolates were within the variation limits observed with the LE strain of S. mansoni.

Phase variation of Haemophilus influenzae lipopolysaccharide: characterization of lipopolysaccharide from individual colonies.

The lipopolysaccharide (LPS) of Haemophilus influenzae expresses a number of core oligosaccharide epitopes on its outer surface. The expression of individual epitopes is subject to frequent (approximately 1% bacteria/generation) reversible phase variation, as determined by colony immunoblots. We have used a microtechnique for the extraction of LPS from individual colonies, whose LPS antigenic phenotype has been identified, so that the LPS can be studied by tricine sodium dodecylsulphate polyacrylamide gel electrophoresis (T-SDS-PAGE). This avoids the introduction of heterogeneous phase-varying LPS which is inevitable if bacteria from colonies are grown in broth culture prior to LPS extraction and analysis. Using these techniques we have investigated the repertoire of LPS phase variation exhibited by H. influenzae strain RM7004 (a serotype b meningitis isolate). This technique will facilitate the study of bacteria in which there is variable LPS expression.

Knowledge, behavior, and fears concerning breast and cervical cancer among older low-income Mexican-American women.

INTRODUCTION: Although recent studies have documented the low participation level of Hispanic women in cancer screening, few have examined their predisposing knowledge and attitudes concerning cancer. We documented the knowledge and fears concerning cancer of an older population of Mexican-American women and how these factors relate to screening behavior and sociodemographic characteristics. METHODS: The data are from baseline surveys conducted before the start of a community cancer awareness and prevention program. Nine hundred twenty-three Mexican-American women were interviewed in-person about their knowledge, attitudes, and Pap smear and mammogram screening practices. RESULTS: Knowledge and attitude about cancer varied with age, education, type of health insurance, ability to speak English, and place of birth. Women 65 years of age and older were least knowledgeable of cancer-detection methods and screening guidelines. Those with only Medicare or Medicaid knew far less even compared to uninsured women. Women who did not speak English well were more likely not to know the cancer signs and symptoms, risk factors, and screening guidelines. Women who had knowledge of guidelines and detection methods were more likely to have had a recent screening. Older Mexican-American women with more fatalistic and fearful attitudes toward cancer were less likely to have had a recent Pap smear. CONCLUSIONS: The low screening participation among Mexican-American women may be due to their limited awareness and knowledge about breast and cervical cancer screening examinations. Our study highlights the need for wide-scale cancer screening interventions consistent with Mexican-American beliefs.

Why a peer intervention program for Mexican-American women failed to modify the secular trend in cancer screening.

INTRODUCTION: We evaluated an intervention program for Mexican-American women to increase Pap smear and mammography screening. METHODS: The three-year intervention included the presentation of role models in the media and reinforcement by peer volunteers. We used a two-community (intervention and comparison) pre-post test design. Activities were targeted to a mainly Spanish-speaking, poverty-level, immigrant population. Pre- and postintervention screening rates were based on independent random samples of Mexican-American women 40 years and older. RESULTS: Women reported a 6% absolute increase in Pap smear use similar to the 7% increase in the comparison community. Both communities experienced large but similar increases in recent mammography use (17% and 19%). Adjusting for differences in demographic factors, intervention and comparison changes remained identical. CONCLUSIONS: Our peer intervention failed to accelerate the secular trend in cancer screening low-income Mexican-American women. Likely, promotional activities were too diffuse and the comparison community was contaminated with similar interventions. Strong social and market forces make it difficult to measure the effect of a specialized intervention on cancer screening rates.

Visual acuity and motor characteristics in congenital nystagmus.

Improvement in visual acuity at near fixation in patients with congenital nystagmus has been explained on the basis of nystagmus damping, caused by superimposed convergence innervation. However, an electronystagmographic study of 13 patients with congenital nystagmus and improvement in visual acuity at near fixation failed to show a consistent decrease of nystagmus intensity at near fixation. Visual acuity at near fixation improved regardless of whether the nystagmus intensity decreased or increased. Factors other than nystagmus amplitude or frequency may be modified by convergence innervation and cause an increase in visual acuity at near in patients with congenital nystagmus.

The metabolic response to rapid intravenous glucose injection in acute falciparum malaria.

Because hypoglycaemia is common in severe malaria, intravenous glucose is often given empirically to patients on admission to hospital. To investigate the metabolic response to rapid glucose injection in acute malaria, 50 ml of 50% w/v (25 g) dextrose was given over 5 min to 10 adult patients (7 males, 3 females; mean age 30 years) with acute falciparum malaria. Five patients with severe infections were studied between doses of intravenous quinine; 5 cases were uncomplicated and previously untreated. The patients with severe malaria had lower pre-injection plasma glucose concentrations than patients with uncomplicated infections (mean +/- standard deviation, 4.2 +/- 0.9 vs 5.8 +/- 1.1 mmol/litre, 2P less than 0.015). However, peak glucose concentrations (18.6 +/- 4.8 vs 17.0 +/- 2.4 mmol/litre) and integrated responses (AUC0-245 min) were similar in the groups (2P greater than 0.1 in each case), and pre- and post-injection plasma insulin concentrations and AUC0-245 min values were also not significantly different (2P greater than 0.05 in each case). No 'rebound' hypoglycaemia was observed. The patients with severe malaria had higher peak plasma lactate concentrations than the uncomplicated patients (2.5 +/- 0.7 vs 1.5 +/- 0.9 mmol/litre, 2P less than 0.05), but the highest plasma lactate achieved and the greatest maximum post-injection rise were only 3.8 and 0.8 mmol/litre respectively. The average maximum reduction in plasma potassium after injection was 0.2 mmol/litre at 35 min. These data suggest that injections of hypertonic dextrose given empirically in conventional doses to non-acidotic patients with acute, severe malaria are not harmful, but the metabolic response in patients with an established acidosis remains unknown.

The thermodynamics of calcium binding to thermolysin.

Calcium binding isotherms were determined for thermolysin in the range pH 5.6-10.5, and from 5 to 45 degrees C. An extensive statistical analysis of the binding data suggests that at least two of the four binding sites bind Ca2+ with complete positive cooperativity and independently of the other two. Nonlinear regression analysis of the binding data was used to calculate cooperative (K1) and independent (K2) binding constants for the four calcium sites. Thermodynamic parameters obtained from a van't Hoff analysis indicate that calcium binding to both cooperative and independent sites is an entropy-driven process. At pH 7.0, delta H1 = 90.4 kJ/mol; delta H2 = 97.5 kJ/mol; delta S1 = 456 J K-1 mol-1; delta S2 = 262 J K-1 mol-1. These results are compared to those obtained for other calcium-binding proteins. An analysis of the pH dependence of the calcium binding constants indicates that the binding of four protons at the cooperative site and one to two protons at the independent sites, modulates the calcium affinity. This confirms an earlier structural assignment of the double-site as the locus of the two cooperatively binding Ca2+. Calcium binding to thermolysin is enhanced in the presence of an active site directed inhibitor, suggesting that there may be positive cooperativity between substrate and calcium binding.

Perianal extramammary Paget's disease. Report of two cases.

Perianal (extramammary) Paget's disease is rare and corresponds to an intraepithelial adenocarcinoma arising from dermal apocrine sweat glands. Biopsy reveals the diagnosis. The condition is often associated with an underlying malignancy (carcinoma of the apocrine or eccrine glands, rectal carcinoma, anal carcinoma). Wide local excision is recommended when invasive growth is absent. For invasive cancer or when associated with a synchronous malignancy abdomino-perineal resection is the treatment of choice. Two cases of perianal Paget's disease are presented.

Epidemiological data and costs of burn injuries in workers in Switzerland: an argument for immediate treatment in burn centres.

A complete statistical evaluation of epidemiological data and costs of burn injuries in 1984 with a follow-up for 5 years is presented, considering a collective of 1.77 million workers in Switzerland. The majority of burns are minor injuries; only about 5 per cent of the burn victims are admitted to a hospital, 0.2 per cent died. Burn injuries at work are rare, mainly owing to strict safety measures. Only one-fifth of the costs caused by burns are due to medical treatment. All other expenses result from continuation of payments of salaries and annuities. The treatment of the few severely burned patients in burn units produces effective costs which are higher than the tariff paid by the insurance. Even so, the predominant portion of the enormous costs is taken up by wages while off work and annuities. As our conclusion we stress the importance of primary care for all severe burns including all burns of the hands in a specialized centre. Any economic effort for primary burn treatment, however high it may be, is justified if the duration of rehabilitation and invalidity can be reduced.