[Clinical characteristics and prognosis of 8 cases of severe infant botulism]

Objective: To summarize the clinical characteristics and prognosis of severe infant botulism and evaluate the therapeutic effect of botulinum antitoxin in the pediatric intensive care unit (PICU). Methods: The clinical data of 8 cases diagnosed with infantile botulism were retrospectively analyzed in the PICU of Beijing Children's Hospital from October 2019 to August 2023. Data of basic demographic information, clinical manifestations, laboratory tests, treatment and prognosis of each child were collected and analyzed using descriptive statistical methods. Results: Eight laboratory-confirmed cases of infant botulism were included in this study, all of which were male infants with an age of 6.0 (3.3,6.8) months. Three of the children were from Inner Mongolia Autonomous Region, 2 of them were from Hebei, and the other 3 were from Beijing, Shandong and Xinjiang Uyghur Autonomous Region, respectively. All the patients were previously healthy. In 4 of these cases, the possible cause was the ingestion of either honey and its products or sealed pickled food by the mother or child before the onset of the disease. The first symptom was poor milk intake (4 cases), followed by shallow shortness of breath (7 cases), limb weakness (7 cases) and so on. The typical signs were bilateral dilated pupils (8 cases) and decreased limb muscle strength (8 cases). The main subtype was type B (7 cases), and only 1 case was classified as type A. Six of the children were treated with antitoxin therapy for a duration of 24 (19, 49) d. Seven of them had invasive mechanical ventilation. All the patients survived upon discharge with a follow-up period of 29 d to 3 years and 8 months. Six patients had fully recovered, and 2 recently discharged patients were gradually recovering. Conclusions: For infants with suspected contact or ingestion of botulinum and presented with bilateral pupillary paralysis, muscle weakness and clear consciousness, the stool should be collected for diagnostic testing using a mouse bioassay as soon as possible. Type B was the most common type. The antitoxin treatment was effectiveness and the prognosis was well.

Dietary non-phytate phosphorus requirements for optimal productive and reproductive performance, and egg and tibial quality in egg-type duck breeders

Optimal dietary non-phytate phosphorus (NPP) is essential in poultry to maximise productive and reproductive performance, along with indices of egg and bone quality. This study aimed to establish the NPP requirements of egg-type duck breeders aged from 54 to 80 weeks on the following traits: egg production, egg incubation, egg quality, tibial characteristics, reproductive organ, plasma indices, and the expression of genes related to phosphorus absorption. Longyan duck breeders aged 54 weeks (n = 300) were randomly allotted to five treatments, each containing six replicates of 10 individually caged birds. Birds were fed corn-soybean meal-based diets containing 0.18, 0.25, 0.32, 0.38, and 0.45% NPP/kg for 27 weeks. The tested dietary NPP levels did not affect egg production or egg quality indices. The hatchling weight of ducklings increased (quadratic, P < 0.01) as dietary NPP level increased, and the highest value occurred with 0.25% NPP. The number of large yellow follicles (LYF), and the relative weights of LYF and ovary showed linear and quadratic responses to dietary NPP levels; the lowest number and relative weight of LYF occurred with 0.38% NPP, and the lowest ovarian weight was obtained with 0.25% NPP. There were no differences in tibial length, breaking strength, and mineral density in response to dietary NPP levels. In contrast, tibial content of Ca increased (linear, P < 0.01) with dietary NPP levels increasing from 0.18 to 0.45%, and the tibial content of P increased at 0.32% NPP and the higher dietary NPP levels. Plasma concentration of P showed a quadratic (P < 0.05) response to the dietary NPP levels, where the highest value was seen at 0.38% NPP. In conclusion, dietary NPP levels from 0.18 to 0.45% had no effects on egg production, and egg and tibial quality of duck breeders. The duck breeders fed a diet with 0.25% NPP showed the highest hatchling weight of their offspring, while those fed 0.38% NPP had the lowest number and relative weight of LYF. These results indicated that the diet with 0.25% NPP can be used in egg-type duck breeders to improve the hatchling weight of their offspring, without adverse effects on their productivity. The regression model indicated that the maximal hatchling weight of ducklings was obtained from duck breeders fed the diet with 0.30% NPP.

[Analysis of risk factors of mortality in infants and toddlers with moderate to severe pediatric acute respiratory distress syndrome]

Objective: To identify the risk factors in mortality of pediatric acute respiratory distress syndrome (PARDS) in pediatric intensive care unit (PICU). Methods: Second analysis of the data collected in the "efficacy of pulmonary surfactant (PS) in the treatment of children with moderate to severe PARDS" program. Retrospective case summary of the risk factors of mortality of children with moderate to severe PARDS who admitted in 14 participating tertiary PICU between December 2016 to December 2021. Differences in general condition, underlying diseases, oxygenation index, and mechanical ventilation were compared after the group was divided by survival at PICU discharge. When comparing between groups, the Mann-Whitney U test was used for measurement data, and the chi-square test was used for counting data. Receiver Operating Characteristic (ROC) curves were used to assess the accuracy of oxygen index (OI) in predicting mortality. Multivariate Logistic regression analysis was used to identify the risk factors for mortality. Results: Among 101 children with moderate to severe PARDS, 63 (62.4%) were males, 38 (37.6%) were females, aged (12±8) months. There were 23 cases in the non-survival group and 78 cases in the survival group. The combined rates of underlying diseases (52.2% (12/23) vs. 29.5% (23/78), χ²=4.04, P=0.045) and immune deficiency (30.4% (7/23) vs. 11.5% (9/78), χ²=4.76, P=0.029) in non-survival patients were significantly higher than those in survival patients, while the use of pulmonary surfactant (PS) was significantly lower (8.7% (2/23) vs. 41.0% (32/78), χ²=8.31, P=0.004). No significant differences existed in age, sex, pediatric critical illness score, etiology of PARDS, mechanical ventilation mode and fluid balance within 72 h (all P>0.05). OI on the first day (11.9(8.3, 17.1) vs.15.5(11.7, 23.0)), the second day (10.1(7.6, 16.6) vs.14.8(9.3, 26.2)) and the third day (9.2(6.6, 16.6) vs. 16.7(11.2, 31.4)) after PARDS identified were all higher in non-survival group compared to survival group (Z=-2.70, -2.52, -3.79 respectively, all P<0.05), and the improvement of OI in non-survival group was worse (0.03(-0.32, 0.31) vs. 0.32(-0.02, 0.56), Z=-2.49, P=0.013). ROC curve analysis showed that the OI on the thind day was more appropriate in predicting in-hospital mortality (area under the curve= 0.76, standard error 0.05,95%CI 0.65-0.87,P<0.001). When OI was set at 11.1, the sensitivity was 78.3% (95%CI 58.1%-90.3%), and the specificity was 60.3% (95%CI 49.2%-70.4%). Multivariate Logistic regression analysis showed that after adjusting for age, sex, pediatric critical illness score and fluid load within 72 h, no use of PS (OR=11.26, 95%CI 2.19-57.95, P=0.004), OI value on the third day (OR=7.93, 95%CI 1.51-41.69, P=0.014), and companied with immunodeficiency (OR=4.72, 95%CI 1.17-19.02, P=0.029) were independent risk factors for mortality in children with PARDS. Conclusions: The mortality of patients with moderate to severe PARDS is high, and immunodeficiency, no use of PS and OI on the third day after PARDS identified are the independent risk factors related to mortality. The OI on the third day after PARDS identified could be used to predict mortality.

The Influence of Saliva and Blood Contamination on Bonding Between Resin-modified Glass Ionomer Cements and Resin Composite

OBJECTIVE

To investigate the influence of blood and saliva contamination on the microshear bond strength (μSBS) between resin-modified glass ionomer cement (RMGIC) and resin composite (RC).

METHODS AND MATERIALS

Eighty RMGIC discs were allocated into four groups (n=20). Group 1 received universal dental adhesive application in a self-etch mode followed by a build-up with RC. Group 2 received saliva as a contaminant, Group 3 received blood as a contaminant, Group 4 received a 1:1 blood-saliva mixture as a contaminant. Specimens from Groups 2, 3, and 4 were submerged into their respective contaminants for 15 seconds and dried prior to the adhesive application, followed by the protocol for Group 1. All specimens were stored in distilled water for 24 hours. Subsequently, the bonded specimens were subjected to μSBS testing using a universal testing machine. Failure mode of the debonded RMGIC surfaces was examined using scanning electron microscopy.

RESULTS

The μSBS from groups 1-4 were 10.76 ± 3.03 MPa, 9.36 ± 2.54 MPa, 6.55 ± 1.67 MPa and 8.42 ± 2.79 MPa, respectively. Contamination by blood and blood-saliva significantly decreased the μSBS (p<0.001, p=0.029). Saliva contamination alone had no statistically significant effect on the μSBS (p=0.524). A statistically significant difference in the mode of failure was detected between the experimental groups (p=0.012).

CONCLUSION

Saliva contamination has no influence on μSBS between RMGIC and RC when it is dried thoroughly, while blood and blood-saliva contamination reduced μSBS between RMGIC and RC even when dried thoroughly.

Effects of dietary inclusion of cassava starch-extraction-residue meal on egg production, egg quality, oxidative status, and yolk fatty acid profile in laying ducks

This study was designed to evaluate the effects of different dietary levels of cassava starch extraction residue meal (CReM) on egg production, egg quality, oxidative status, egg yolk fatty acid profile, and hepatic expression of fatty acid metabolism-related genes. In total, 288 Longyan laying ducks aged 21 wk with similar BW were randomly assigned to 4 dietary treatments, each consisting of 6 replicates of 12 birds. The birds were fed a typical corn-soybean meal diet, which contained 0% (control), 5%, 10%, and 15% CReM, mainly replacing wheat bran, and the experiment lasted for 16 wk. The tested CReM levels did not show significant effects on the egg production, nonmarketable egg percentage, egg weight, daily egg mass, and FCR (g feed: g egg), but daily feed intake was reduced with increased CReM level (linear P < 0.001, quadratic P < 0.05). Yolk color increased (linear and quadratic, P < 0.01) with the increase in CReM level, but the Haugh unit, yolk proportion, albumen proportion, shell proportion, eggshell thickness, and eggshell strength were unaffected. Yolk contents of C11:0 and C12:0 (linear, quadratic, P < 0.01) and total saturated fatty acids increased, and the C22:1 level decreased (linear P < 0.01, quadratic P < 0.05) with the increase in CReM level, but the total monounsaturated fatty acids, the individual and total polyunsaturated fatty acids and n−6 and n−3 fatty acids, triglycerides, and total cholesterol in egg yolk were not affected. Hepatic gene expression revealed a significant increase in peroxisome proliferators-activated receptors γ (linear, quadratic, P < 0.001), but the expression of fatty acid synthase, sterol regulatory element binding protein 1 and apolipoprotein A1 genes were unaffected by CReM level. In conclusion, the results of the current study indicated that the CReM could be included up to 15% in laying duck diets without negative effects on the egg-laying rate, egg quality, and oxidative status. Dietary inclusion of CReM increased the yolk content of total saturated fatty acids and SOD activity in the liver.

Evaluation of developmentally hypomineralised enamel after surface pretreatment with Papacarie Duo gel and different etching modes: an in vitro SEM and AFM study

PURPOSE

This study aimed at investigating the surface morphology and nanotopography of normal enamel (NE) and developmentally hypomineralised enamel (HE) when subjected to various pretreatment protocols under scanning electron microscopy (SEM) and atomic force microscopy (AFM).

METHODS

Sixteen NE, 16 creamy/white (CW) HE and 16 yellow/brown (YB) HE specimens sectioned from extracted hypomineralised first permanent molars (FPMs) were included in this study. They were randomly distributed into 12 experimental groups (n = 4). Each group involved the following: (1) deproteinisation with Papacarie Duo^® gel or no deproteinisation, and (2) the use of Scotchbond™ Universal Adhesive (Scotchbond) in self-etch (SE) mode or 37% phosphoric acid etchant. Subsequently, the surface morphology and nanotopography of pretreated enamel specimens were evaluated under SEM and AFM, respectively.

RESULTS

SEM observation showed that deproteinisation with Papacarie Duo^® gel before phosphoric acid etching led to favourable etching patterns. This was consistent across all groups irrespective of the type of enamel specimen and the severity of hypomineralisation. In contrast, AFM results identified three factors that influenced surface parameters: (1) type of enamel specimen, (2) severity of hypomineralisation and (3) etching mode. YB HE recorded higher surface roughness values than CW HE and NE when subjected to the same pretreatment protocol. Deproteinisation and the application of Scotchbond in SE mode led to minimal topographic changes; however, acid etching was associated with an increase in surface roughness.

CONCLUSION

Deproteinisation with Papacarie Duo^® gel followed by acid etching contributed to improved etching patterns on HE.

Effects of maternal and progeny dietary selenium supplementation on growth performance and antioxidant capacity in ducklings

This study evaluated the effects of selenium (Se) supplementation in maternal and offspring diets on performance and antioxidant capacity of ducklings aged from 0 to 2 wk. A total of 144 female Longyan duck breeders aged 22-wk were allotted into 2 treatments and fed a control diet or a 0.16 mg Se/kg supplemented diet. At 40-wk, 120 offspring from each treatment were divided into 2 groups, with 6 replicates of 10 birds. Using a 2 × 2 factorial design, ducklings from each maternal dietary treatment were assigned to a control diet or a 0.16 mg Se/kg supplemented diet from hatch to 2-wk. Compared with Se-deficient diet, maternal diet supplemented with 0.16 mg Se/kg increased the BW of hatchlings (P < 0.01). There were interactions between maternal and progeny diet with 0.16 mg Se/kg in BW of ducklings aged 2 wk and BW gain (BWG) as ducklings from maternal Se/progeny none treatment had the lightest BW and BWG (P < 0.01). Maternal diet with 0.16 mg Se/kg decreased plasma concentration of uric acid and insulin-like growth factor 1 (P < 0.01), and progeny diet supplemented with 0.16 mg Se/kg increased the activities of glutathione peroxidase 3 (GPx3) in plasma and glutathione peroxidase 1 in erythrocyte (P < 0.01). Maternal diet with 0.16 mg Se/kg increased (P < 0.05) the hepatic activity of total superoxide dismutase (T-SOD). Progeny diet supplemented with 0.16 mg Se/kg increased (P < 0.01) hepatic activity of GPx3 and decreased (P < 0.01) the hepatic concentration of malondialdehyde. Interactions were detected between maternal and progeny diet with 0.16 mg Se/kg in hepatic activity of T-SOD and maternal and progeny diet supplemented with Se displayed the highest hepatic activity of T-SOD (P < 0.05). Overall, Se supplementation in the diet of duck breeders and offspring increased the antioxidant capacity of ducklings. Maternal Se supplementation increased the BW of hatchlings, whereas maternal and progeny dietary Se supplementation did not affect the BWG of ducklings aged from 0 to 2 wk. Se supplementation with additional 0.16 mg/kg in the diet of duck breeders and offspring displayed beneficial effects particularly on the antioxidant capacity in ducklings.

Impact of appropriate empirical antibiotics on clinical outcomes in Klebsiella pneumoniae bacteraemia

INTRODUCTION

Klebsiella pneumoniae infections can cause septic shock, multiorgan failure, and death.

METHODS

This retrospective cohort study included adults with K pneumoniae bacteraemia treated from 1 January 2009 to 30 June 2017. Demographics, microbiology, and outcomes were analysed. The primary outcome was 90-day all-cause mortality; secondary outcomes were intensive care unit (ICU) and hospital mortalities, ICU and hospital lengths of stay, and ICU ventilator duration.

RESULTS

In total, 984 patients had K pneumoniae bacteraemia; of them, 686 received appropriate empirical antibiotics. Overall, 205 patients required intensive care. Older age (odds ratio [OR]=1.60; 95% confidence interval [CI]=1.120-2.295; P=0.010), chronic kidney disease (OR=1.81; 95% CI=1.181- 2.785; P=0.007), mechanical ventilation (OR=1.79; 95% CI=1.188-2.681; P=0.005), pneumonia (OR=1.50; 95% CI=1.030-2.187; P=0.034), and carbapenem-resistant or extended-spectrum betalactamase (ESBL)-producing isolates (OR=12.51; 95% CI=7.886-19.487; P<0.001) were associated with greater risk of inappropriate empirical treatment. Ninety-day mortality was significantly higher among patients with inappropriate empirical treatment; independent predictors included pneumonia (hazard ratio [HR]=2.94; 95% CI=2.271-3.808; P<0.001), gastrointestinal infection (HR=2.77; 95% CI=2.055-3.744; P<0.001), failed empirical antibiotics (HR=2.45; 95% CI=1.928-3.124; P<0.001), older age (HR=1.79; 95% CI=1.356-2.371; P<0.001), solid tumour (HR=1.77; 95% CI=1.401-2.231; P<0.001), carbapenem-resistant or ESBL-producing isolates (HR=1.64; 95% CI=1.170-2.297; P=0.004), patients admitted through the Department of Medicine (HR=1.39; 95% CI=1.076-1.800; P=0.012), and higher total Sequential Organ Failure Assessment score (HR=1.09; 95% CI=1.058-1.112; P=0.023). Among ICU patients, inappropriate empirical antibiotic treatment was significantly associated with increased ventilator duration and 90-day mortality.

CONCLUSIONS

Klebsiella pneumoniae bacteraemia was associated with high 90-day and ICU mortalities; 90-day mortality increased with inappropriate empirical antibiotic treatment.

Estimation of dietary tryptophan requirement for laying duck breeders: effects on productive and reproductive performance, egg quality, reproductive organ and ovarian follicle development and serum biochemical indices

This study aimed to determine the dietary tryptophan (Trp) requirement for laying duck breeders. A total of 504 Longyan duck breeders (body weight: 1.20 ± 0.02 kg) aged 22 wk were randomly allocated to 6 treatments, each with 6 replicates of 14 ducks. During the next 16 wk, birds were fed the basal diet with total Trp contents of 1.00, 2.00, 3.00, 4.00, 5.00 and 6.00 g/kg, respectively. Dietary Trp levels increased egg production, egg mass and feed intake of duck breeders from 22 to 37 wk (P < 0.05), and there were linear and quadratic effects of Trp level (P < 0.05). The feed conversion ratio (FCR) quadratically decreased with dietary Trp levels (P < 0.05). Dietary Trp levels decreased (P < 0.05) egg albumen height and Haugh unit at wk 8 or 12, and the responses were linear and quadratic (P < 0.05). The body weight of breeders, absolute and relative weight of oviduct, number and total weight of preovulatory follicles (POF), and its proportion relative to ovarian weight were increased (P < 0.05), and the responses were linear (P < 0.01) and quadratic (P < 0.001). Ovarian weight increased quadratically (P < 0.05), and the mean weight of POF increased (P < 0.05), linearly and quadratically. The proportion of small yellow follicles relative to ovary weight decreased (P < 0.01) linearly and quadratically. At wk 16 of the trial period, the serum albumin content and alanine aminotransferase activity decreased (P < 0.05) and the creatinine content increased (P < 0.01) linearly and quadratically. The Trp requirements were estimated to be 3.14 g/kg for optimizing egg production, 2.93 g/kg for egg mass, and 2.92 g/kg for FCR. Overall, dietary Trp levels (1 to 6 g/kg) affected productive performance, egg quality, reproductive organ and ovarian follicle development, and serum biochemical indices of layer duck breeders, and a diet containing 2.9 to 3.1 g Trp per kg feed was adequate during the laying period (22 to 37 wk of age).

[Analysis of 39 children with acute necrotizing encephalopathy]

Objective: To investigate the risk factors for death in children with acute necrotizing encephalopathy (ANE) in pediatric intensive care unit (PICU). Methods: This was a multicenter retrospective study. Thirty-nine children with ANE were from PICUs in 4 centers from December 1, 2014 to December 1, 2020. The 4 participating centers were Beijing Children's Hospital, Shengjing Hospital of China Medical University, Hebei Children's Hospital, and Bao'an Maternity & Child Health Hospital. Patients were divided into survival and non-survival groups by the outcome at discharge, and the differences in clinical data between the two groups were compared. Risk factors for death in children with ANE and the odds ratios (OR) were analyzed by univariable Logistic regression. Results: Thirty-nine children with ANE were included. There were 18 males and 21 females. The median onset age was 30 months. The mortality at discharge was 41% (16/39). The onset age of most patients (74%, 29/39) was younger than 4 years old. Influenza virus was the most common precursor infection (80%, 20/25). Patients with shock at PICU admission were more common in the non-survival group (12/16 vs. 17% (4/23), P=0.001). Glasgow coma score (GCS) at PICU admission was significantly lower in the non-survival group than survival group (3 (3, 6) vs. 6 (5, 7), Z=-2.598, P=0.009). The optimal cut-off value was 4. The proportion of patients with GCS ≤ 4 at PICU admission was higher in the non-survival group (10/16 vs. 22% (5/23), P=0.018). ANE severity score (ANE-SS) at PICU admission was significantly higher in the non-survival group (5 (2, 6) vs. 2 (1, 4), Z=-2.436, P=0.015). The proportion of patients with high risk ANE-SS was higher in non-survival group than the survival group (9/16 vs. 22% (5/23), P=0.043). The proportion of application of high-dose methylprednisolone (20 mg/(kg·d)) was significantly higher in survival group than non-survival group (43% (10/23) vs. 1/13, P=0.031). Univariable Logistic regression indicated that risk factors for death in children with ANE were shock (OR=14.250, 95%CI 2.985-68.018, P=0.001), GCS≤4 (OR=6.000, 95%CI 1.456-24.733, P=0.013) and high risk ANE-SS (OR=4.629, 95%CI 1.142-18.752, P=0.032) at PICU admission. Conclusions: ANE usually occurs in children under 4 years old after influenza infection. Shock, GCS≤4 and high risk ANE-SS at PICU admission were risk factors for death in children with ANE. High-dose methylprednisolone may improve the prognosis of children with ANE.

FXYD6 promotes thermal nociception by regulating TRPV1

FXYD6, an unnecessary auxiliary subunit of Na⁺,K⁺-ATPase, is expressed in the nervous system. However, its functions remain largely unclear. In the present study, we find that FXYD6 is involved in the thermal nociception. FXYD6 was mainly expressed in small-diameter DRG neurons expressing transient receptor potential channel V1 (TRPV1). In the SNS-Cre/Fxyd6^F/F mice, loss of FXYD6 in these sensory neurons impaired the behavioral responses to noxious heat stimulus and intraplantar injection of capsaicin. The capsaicin-induced and TRPV1-mediated currents were decreased in the FXYD6–deficient DRG neurons. Heterologous expression of FXYD6 could increase the TRPV1 capsaicin-sensitive currents in HEK293 cells. Furthermore, we found that the negatively charged PGDEE motif in C-terminal of FXYD6 is required for the FXYD6/TRPV1 interaction and FXYD6-mediated enhancement of TRPV1. Disrupting the FXYD6/TRPV1 interaction with the TAT-PGDEE peptide could elevate the threshold of thermal nociception. Therefore, FXYD6 maintains the thermal nociception via interacting with TRPV1 channel in nociceptors.

The application of reduced dietary crude protein levels supplemented with additional amino acids in laying ducks

This study was aimed at studying use of reduced dietary crude protein (CP) level supplemented with additional amino acids in laying ducks. A total of 720 Jingjiang ducks (50 wk) were randomly assigned to 5 treatments and fed 5 basal diets with CP levels at 17.5, 16.5, 15.5, 14.5, or 13.5%, with additional amino acids added to each diet for 12 wk. Each treatment had 6 replicates of 24 ducks each. Dietary CP levels affected (P < 0.05) egg production and mass of laying ducks, and there was a linear and quadratic decrease with decreasing CP levels (P < 0.05). Dietary CP levels did not affect egg weight and feed conversion ratio (FCR), but egg weight decreased linearly (P < 0.05); FCR increased linearly and quadratically (P < 0.05) with decreasing CP levels. There were no significant differences in egg quality among the different CP levels (P > 0.05). Ovarian weight, total and mean weight of preovulatory follicles, and total weight of small yellow follicles (SYF) were decreased by dietary CP levels (linear, P < 0.01 and quadratic, P < 0.05). The oviductal weight decreased linearly (P < 0.05), and the number of SYF decreased linearly and quadratically with decreasing CP levels (P < 0.05). The serum estradiol content decreased linearly with dietary CP levels (P < 0.05). The serum contents of luteinizing hormone, prolactin, and progesterone decreased (P < 0.05), linearly and quadratically (both P < 0.01) with decreasing CP levels. The serum contents of creatinine (CRE), triglycerides (TG), total cholesterol (TC), and alanine aminotransferase (ALT) activity were affected (P < 0.05) by different dietary CP levels. The total protein content increased linearly (P < 0.05), TC content increased quadratically (P < 0.05), and contents of albumin, CRE, TG, and phosphorus, and activities of aspartate aminotransferase and ALT increased linearly and quadratically (both P < 0.05) with decreasing CP levels. Overall, reduced dietary CP levels with addition of amino acids affected the laying performance, the development of reproductive organs and ovarian follicles, serum hormones, and biochemical indices of laying ducks. Dietary CP levels can be reduced to 14.5% with additional amino acid supplementation for 12 wk in laying ducks without negative effect on laying performance and egg quality.

Effects of capsaicin on laying performance, follicle development, and ovarian antioxidant capacity in aged laying ducks

The present study was conducted to evaluate the effects of dietary addition of capsaicin (CAP) on egg production performance, follicular development, and ovarian antioxidant capacity in laying ducks. Three hundred seventy eight 58-wk-old laying ducks were randomly divided into 3 treatments, each treatment consisted 6 replicates, with 12 individually caged laying ducks per replicate. Ducks fed a basal diet served as control, the other 2 groups of ducks were fed the same diet containing 150 mg/kg CAP but in the manner of feed restriction (pair-fed) or ad libitum fed. The experiment lasted for 8 wk. The results showed that the dietary supplementation with CAP under conditions of ad libitum feeding increased feed intake (P < 0.001) and tended (P < 0.1) to increase egg production and egg weight in laying ducks but had no effects on daily egg mass and feed conversion ratio. The relative weight of large yellow follicles from the 2 CAP-supplemented groups at 64 wk of age were significantly higher than that of the controls (P = 0.01). The relative weight of the small yellow follicles in the CAP free-fed group was significantly higher than that of the other 2 groups (P < 0.01). Capsaicin supplementation under ad libitum feding conditions tended to increase the number of dominant follicles in laying ducks (P = 0.06). The ovarian mRNA expression of genes related to calcium signaling (TRPV4, ATP2A2, ITPR1, and CaM) in the CAP ad libitum fed groups were significantly higher than those of the other 2 groups (P < 0.05). The ovarian mRNA expression of CDK1 in CAP free-fed ducks was significantly higher than that of the other 2 groups (P = 0.01). Capsaicin supplementation significantly increased the plasma glutathione peroxidase activity (P < 0.01) in comparison with the control group but reduced the malondialdehyde content in the ovaries of laying ducks (P < 0.01). The results of this study indicates that dietary supplementation of CAP increased feed intake and improved egg production performance probably by activating calcium signaling pathway and improving redox status.

Estimation of dietary manganese requirement for laying duck breeders: effects on productive and reproductive performance, egg quality, tibial characteristics, and serum biochemical and antioxidant indices

This study was aimed at estimating the dietary manganese (Mn) requirement for laying duck breeders. A total of 504 Longyan duck breeders (body weight: 1.20 ± 0.02 kg) aged 17 wk were randomly allocated to 6 treatments. The birds were fed with a basal diet (Mn, 17.5 mg/kg) or diets supplemented with 20, 40, 80, 120, or 160 mg/kg of Mn (as MnSO₄·H₂O) for 18 wk. Each treatment had 6 replicates of 14 ducks each. As a result of this study, dietary Mn supplementation did not affect the productive performance of laying duck breeders in the early laying period (17–18 wk), but affected egg production, egg mass, and feed conversion ratio (FCR) from 19 to 34 wk (P < 0.05), and there was a linear and quadratic effect of supplement level (P < 0.05). The proportion of preovulatory ovarian follicles increased (P < 0.01) linearly and quadratically, and atretic follicles (weight and percentage) decreased (P < 0.05) quadratically with dietary Mn supplementation. The density and breaking strength of tibias increased (quadratic; P < 0.05), the calcium content of tibias decreased (linear, quadratic; P < 0.01), and Mn content increased (linear, quadratic; P < 0.001) with increase in Mn. The addition of Mn had a quadratic effect on serum contents of estradiol, prolactin, progesterone, luteinizing hormone, and follicle-stimulating hormone (P < 0.001). Dietary Mn supplementation decreased serum contents of total protein (linear, P < 0.05), glucose (quadratic, P < 0.05), total bilirubin, triglycerides, total cholesterol, low-density lipoprotein cholesterol, and calcium (linear, quadratic; P < 0.05). The serum total antioxidant capacity and total and Mn-containing superoxide dismutase activities increased (linear, quadratic; P < 0.001), and malondialdehyde content decreased (linear, quadratic; P < 0.001) in response to Mn supplemental levels. The dietary Mn requirements, in milligram per kilogram for a basal diet containing 17.5 mg/kg of Mn, for Longyan duck breeders from 19 to 34 wk of age were estimated to be 84.2 for optimizing egg production, 85.8 for egg mass, and 95.0 for FCR. Overall, dietary Mn supplementation, up to 160 mg/kg of feed, affected productive performance, tibial characteristics, and serum biochemical and antioxidant status of layer duck breeders. Supplementing this basal diet (17.5 mg/kg of Mn) with 85 to 95 mg/kg of additional Mn was adequate for laying duck breeders during the laying period.

The effects of dietary Se on productive and reproductive performance, tibial quality, and antioxidant capacity in laying duck breeders

This study evaluated the optimal concentrations of dietary Se for the productive and reproductive performance, tibial quality, and antioxidant status in duck breeders aged 23 to 49 wk. In total, 432 Longyan duck breeders aged 22 wk were allotted randomly to 6 treatments, each with 6 replicates of 12 individually caged birds. The experiment lasted for 27 wk, and birds were fed corn-soybean meal-based diets containing 0.11, 0.19, 0.27, 0.35, 0.43, or 0.51 mg Se/kg, respectively. The tested dietary Se levels did not affect egg production and tibial quality of duck breeders. The Se contents of the shell, yolk or albumin, whole egg, and the fertility of set eggs increased in a linear and quadratic manner (P < 0.05) in response to the increased dietary Se level, whereas the yolk malondialdehyde (MDA) and embryonic mortality decreased. The activities of glutathione peroxidase 3 (Gpx3) in plasma and Gpx1 in the erythrocytes and livers of breeder ducks increased in a linear and quadratic manner (P < 0.05) in response to increased dietary Se levels, whereas the total superoxide dismutase (T-SOD) activity increased and the MDA concentration decreased in the liver. The activity of Gpx3 in the plasma and Gpx1 in the erythrocytes and livers of newly hatched ducklings increased linearly (P < 0.01) with the increase in Se level, whereas the T-SOD activity and MDA concentration did not change. In conclusion, diets containing 0.27 mg Se/kg led to the highest egg fertility and hatchability in Longyan duck breeders, and using levels >0.19 mg Se/kg diet enhanced the antioxidant capacity in breeders and their offspring. The regression model indicated that dietary Se levels 0.19, 0.27, 0.28, 0.24, and 0.30 mg/kg are optimal levels to obtain maximum Se deposition efficiency in eggs, egg fertility, Gpx1 activity in erythrocytes and liver in duck breeders, and plasma activity of Gpx3 in newly hatched ducklings, respectively.

Estimation of dietary zinc requirement for laying duck breeders: effects on productive and reproductive performance, egg quality, tibial characteristics, plasma biochemical and antioxidant indices, and zinc deposition

This study evaluated the effects of different dietary zinc (Zn) levels on productive and reproductive performance, egg quality, tibial characteristics, plasma biochemical and antioxidant indices, and zinc deposition in laying duck breeders. A total of 504 Longyan duck breeders aged 21 wk were randomly allocated to 6 treatments and fed a basal diet (Zn, 27.7 mg/kg) or that basal diet supplemented with Zn (as ZnSO₄·H₂ O) at 10, 20, 40, 80, or 160 mg Zn per kg of feed for 20 wk. Each group had 6 replicates of 14 ducks each. Dietary Zn supplementation affected (P < 0.05) the egg production, FCR, and shell thickness of laying duck breeders from 21 to 40 wk, and there was a quadratic (P < 0.05) effect between them. Dietary Zn supplementation affected (P < 0.05) and quadratically (P < 0.001) increased the breaking strength, density, and dry defatted weight of tibias. Alkaline phosphatase, calcium, phosphorus, total superoxide dismutase, glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) activities or content in plasma were affected (P < 0.05), and quadratically (P < 0.01) changed by dietary Zn levels. Dietary Zn supplementation affected (P < 0.01) and increased the Zn deposition in egg yolk (linear, P < 0.05; quadratic, P < 0.001) and tibia (linear, P < 0.05). The dietary Zn requirements, in mg/kg for a basal diet containing 27.7 mg/kg Zn, for Longyan duck breeders from 21 to 40 wk of age were estimated to be 65.4 for optimizing egg production, 68.6 for FCR, 102 for hatchling BW, 94.7 for eggshell thickness, 77.2 for tibial breaking strength, 81.4 for tibial density, 78.9 for tibial dry defatted weight, 69.5 for plasma GSH-Px activity, 72.4 for plasma MDA content, and 94.6 for Zn content in tibia. Overall, dietary Zn supplementation, up to 160 mg/kg feed, affected the productive performance, eggshell thickness, tibial characteristics, plasma antioxidant status, and Zn deposition of layer duck breeders. Supplementing this basal diet (27.7 mg/kg Zn) with 70 to 80 mg/kg additional Zn was adequate for laying duck breeders during the laying period.

Distinct Patterns of Interhemispheric Connectivity in Patients With Early- and Late-Onset Alzheimer's Disease

Background: Early-onset Alzheimer’s disease (EOAD) presents a different clinical profile than late-onset Alzheimer’s disease (LOAD). Neuroimaging studies have demonstrated that patients with EOAD present more atrophy and functional disconnection than LOAD patients. However, it remains unknown whether the interhemispheric functional disconnection or its underlying structural impairment contributes to the different clinical profiles of EOAD and LOAD.

Methods: According to the arbitrary cut-off age of 65, we included 22 EOAD patients, 27 LOAD patients and 38 healthy controls (further divided into 21 relatively young and 17 old controls). Participants underwent resting-state functional MRI, diffusion tensor imaging (DTI) and comprehensive neuropsychological assessments. We used voxel-mirrored homotopic connectivity (VMHC) to examine interhemispheric functional connectivity. Then, we calculated the diffusion index based on tract-based spatial statistics (TBSS). Two-sample t-tests were used to assess the interhemispheric connectivity differences between each patient group and its corresponding control group.

Results: We found that the EOAD patients had lower VMHC in the hippocampus, parahippocampal gyrus (PHG), superior temporal gyrus (STG) and inferior parietal cortex (IPC) than did controls. Consistently, the EOAD patients exhibited white matter (WM) tract impairment in the posterior regions. On the other hand, the LOAD patients displayed increased VMHC and impaired WM tracts in the frontal region. Correlation analyses showed that VMHC in the IPC was related to executive function in the EOAD patients (r = −0.67, P < 0.05).

Conclusion: In contrast to the LOAD patients, patients with EOAD exhibited more widely disrupted interhemispheric functional and structural connectivity, which overlapped well across brain regions. In addition, for the EOAD patients, decreased interhemispheric connectivity related to executive deficits. Our study suggested that different interhemispheric connectivity damage patterns may contribute to the distinct clinical profiles in EOAD and LOAD.

Influence of ageing on glass and resin bonding of dental glass-ceramic veneer adhesion to zirconia: A fracture mechanics analysis and interpretation

Adhesion plays a major role in the bonding of dental materials. In this study the adhesion of two glass-ceramic systems (IPS e.max and VITABLOCS) to a zirconia sintered substrate using a glass (for IPS e.max) and resin (VITABLOCS) before and after exposure to ageing for 14 days in distilled water at 37 °C are compared using two interfacial fracture mechanics tests, the 3 point bend Schwickerath (Kosyfaki and Swain, 2014; Schneider and Swain, 2015) and 4 point bend (Charalambides et al., 1989) approaches. Both tests result in stable crack extension from which the strain energy release rate (G, N/m or J/m²) can be determined. In the case of the 3 PB test the Work of Fracture was also determined. In addition, the Schwickerath test enables determination of the critical stress for the onset of cracking to occur, which forms the basis of the ISO (ISO9693-2:2016) adhesion test for porcelain ceramic adhesion to zirconia. For the aged samples there was a significant reduction in the resin-bonded strengths (Schwickerath) and strain energy release rate (both 3 and 4 PB tests), which was not evident for the glass bonded specimens. Critical examination of the force-displacement curves showed that ageing of the resin resulted in a major change in the form of the curves, which may be interpreted in terms of a reduction in the critical stress to initiate cracking and also in the development of an R-curve. The extent of the reduction in strain energy release rate following ageing was greater for the Schwickerath test than the Charalambides test. The results are discussed in terms of; the basic mechanics of these two tests, the deterioration of the resin bonding following moisture exposure and the different dimensions of the specimens. These in-vitro results raise concerns regarding resin bonding to zirconia.

STATEMENT OF SIGNIFICANCE

The present study uses a novel approach to investigate the role of ageing or environmental degradation on the adhesive bonding of two dental ceramics to zirconia. This continues to be a major clinical problem but current approaches, till now, have relied upon a myriad of strength based tests to quantify the extent of environmental degradation with time. In this paper we use two fracture mechanics approaches, based upon simple 3 and 4 point bend testing procedures that enable stable debonding crack extension to occur. The paper provides a more critical approach to evaluate the role of environmental degradation of adhesion for dental materials.

PDTC ameliorates decompression induced-lung injury caused by unsafe fast buoyancy ascent escape via inhibition of NF-κB pathway

Nuclear factor kappa B (NF-κB) is the critical transcriptional factor in the pathogenesis of acute lung injury (ALI). NF-κB regulates the expression changes of inflammatory factors such as tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β) and interleukin 6 (IL-6). In a previous study we showed that decompression sickness (DCS) caused by simulated unsafe fast buoyancy ascent escape (FBAE) could result in ALI, which was characterized by expression changes of inflammatory factors in rat lung tissue. The purpose of the present work was to study the roles of NF-κB and TNF-α in the process of DCS-induced rat lung injury caused by simulated unsafe FBAE. The research methods aimed to detect the rat lung tissue messenger ribonucleic acid (mRNA) and protein level variations of NF-κB, inhibitory ×B (I×B), TNF-α, IL-1β, IL-6, IL-10 and IL-13 by using pretreatment of the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) and TNF-α antibody (Ab). Our experimental results demonstrated that PDTC could improve the survival rate of the rats with DCS caused by unsafe FBAE more effectively than TNF-α Ab. However, the inhibition of TNF-α Ab on the nuclear translocated protein expression of NF-κB was more effective than PDTC. Both PDTC and TNF-α Ab can abrogate the increment of the rat lung tissue mRNA levels of TNF-α, IL-1β, IL-6 and protein levels of NF-κB, TNF-α, IL-1β effectively and increase the rat lung tissue content of I×B significantly. In conclusion, TNF-α-mediated NF-κB signaling may be one of the critical signaling pathways in the pathogenesis of DCS-induced rat lung injury caused by simulated unsafe FBAE. PDTC may ameliorate this type of injury partly through inhibiting the NF-κB pathway.

[Second-line treatment for metastatic or locally advanced gastric cancer]

Gastric cancer is one of the major causes of cancer-related deaths. Many patients with metastatic gastric cancer after first-line chemotherapy received salvage chemotherapy in routine clinical practice. Recent phase Ⅲ trials demonstrated substantial prolongation of overall survival to support this chemotherapy or targeted therapy as a second-line treatment. Both ramucirumab monotherapy and ramucirumab plus paclitaxel were approved by FDA in patients with previously treated advanced gastric or gastroesophageal junction adenocarcinoma. In addition, paclitaxel, irinotecan, or docetaxel monotherapy is also recommended for preferred regimens. This review will summarize chemotherapy or targeted therapy as a second-line treatment in advanced gastric cancer.

Somatosensory neuron types identified by high-coverage single-cell RNA-sequencing and functional heterogeneity

Sensory neurons are distinguished by distinct signaling networks and receptive characteristics. Thus, sensory neuron types can be defined by linking transcriptome-based neuron typing with the sensory phenotypes. Here we classify somatosensory neurons of the mouse dorsal root ganglion (DRG) by high-coverage single-cell RNA-sequencing (10 950 ± 1 218 genes per neuron) and neuron size-based hierarchical clustering. Moreover, single DRG neurons responding to cutaneous stimuli are recorded using an in vivo whole-cell patch clamp technique and classified by neuron-type genetic markers. Small diameter DRG neurons are classified into one type of low-threshold mechanoreceptor and five types of mechanoheat nociceptors (MHNs). Each of the MHN types is further categorized into two subtypes. Large DRG neurons are categorized into four types, including neurexophilin 1-expressing MHNs and mechanical nociceptors (MNs) expressing BAI1-associated protein 2-like 1 (Baiap2l1). Mechanoreceptors expressing trafficking protein particle complex 3-like and Baiap2l1-marked MNs are subdivided into two subtypes each. These results provide a new system for cataloging somatosensory neurons and their transcriptome databases.

Fstl1 is involved in the regulation of radial glial scaffold development

Background

Radial glial cells (RGCs), the instructive scaffolds for neuronal migration, are well characterized by their unique morphology and polarization; these cells extend elongated basal processes to the pial basement membrane (BM) and parallel to one another. However, little is known about the mechanisms that underlie the developmental regulation and maintenance of this unique morphology.

Results

Here, by crossing Fstl1^fl/fl mice with an EIIa-Cre line, we identified a new role for the secreted glycoprotein Follistatin like-1 (FSTL1). The ablation of Fstl1 in both of its cortical expression domains, the ventricular zone (VZ) and the pia mater, resulted in RGC morphologic disruption; basal processes were not parallel to each other, and endfeet exhibited greater density and branching. However, Fstl1 deletion in only the VZ in the Emx1^IREScre; Fstl1^fl/fl line did not affect RGC morphology, indicating that FSTL1 derived from the pia mater might be more important for RGC morphology. In addition, upper-layer projection neurons, not deeper-layer projection neurons, failed to reach their appropriate positions. We also found that BMP, AKT/PKB, Cdc42, GSK3β, integrin and reelin signals, which have previously been reported to regulate RGC development, were unchanged, indicating that Fstl1 may function through a unique mechanism.

Conclusions

In the present study, we identified a new role for FSTL1 in the development of radial glial scaffolds and the neuronal migration of upper-layer projection neurons. Our findings will improve understanding of the regulation of RGC development and neuronal migration.

Electronic supplementary material

The online version of this article (doi:10.1186/s13041-015-0144-8) contains supplementary material, which is available to authorized users.

Fibroblast growth factor 7 is a nociceptive modulator secreted via large dense-core vesicles

Fibroblast growth factor (FGF) 7, a member of FGF family, is initially found to be secreted from mesenchymal cells to repair epithelial tissues. However, its functions in the nervous system are largely unknown. The present study showed that FGF7 was a neuromodulator localized in the large dense-core vesicles (LDCVs) in nociceptive neurons. FGF7 was mainly expressed in small-diameter neurons of the dorsal root ganglion and could be transported to the dorsal spinal cord. Interestingly, FGF7 was mostly stored in LDCVs that did not contain neuropeptide substance P. Electrophysiological recordings in the spinal cord slice showed that buffer-applied FGF7 increased the amplitude of excitatory post-synaptic current evoked by stimulating the sensory afferent fibers. Behavior tests showed that intrathecally applied FGF7 potentiated the formalin-induced acute nociceptive response. Moreover, both acute and inflammatory nociceptive responses were significantly reduced in Fgf7-deficient mice. These results suggest that FGF7 exerts an excitatory modulation of nociceptive afferent transmission.

FXYD2, a γ subunit of Na⁺, K⁺-ATPase, maintains persistent mechanical allodynia induced by inflammation

Na⁺, K⁺-ATPase (NKA) is required to generate the resting membrane potential in neurons. Nociceptive afferent neurons express not only the α and β subunits of NKA but also the γ subunit FXYD2. However, the neural function of FXYD2 is unknown. The present study shows that FXYD2 in nociceptive neurons is necessary for maintaining the mechanical allodynia induced by peripheral inflammation. FXYD2 interacted with α1NKA and negatively regulated the NKA activity, depolarizing the membrane potential of nociceptive neurons. Mechanical allodynia initiated in FXYD2-deficient mice was abolished 4 days after inflammation, whereas it persisted for at least 3 weeks in wild-type mice. Importantly, the FXYD2/α1NKA interaction gradually increased after inflammation and peaked on day 4 post inflammation, resulting in reduction of NKA activity, depolarization of neuron membrane and facilitation of excitatory afferent neurotransmission. Thus, the increased FXYD2 activity may be a fundamental mechanism underlying the persistent hypersensitivity to pain induced by inflammation.

Expression changes of TNF-α, IL-1β and IL-6 in the rat lung of decompression sickness induced by fast buoyancy ascent escape

Fast buoyancy ascent escape is the general submarine escape manner adopted by the majority of naval forces all over the world. However, if hyperbaric exposure time exceeds the time limit, fast buoyancy ascent escape has a high risk to result in decompression sickness (DCS). Tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and IL-6 have been all implicated in the process of inflammation associated with acute lung injury (ALI). Our work demonstrated that DCS caused by simulated fast buoyancy ascent escape could induce ALβ in the rat model. The purpose of the present work was to study the expression changes of TNF-α, IL-1β and IL-6 in the rat lung affected by DCS caused by simulated fast buoyancy ascent escape. The lung tissue mRNA levels of TNF-α, Il-1β and Il-6 were significantly increased at 0.5 hour after DCS caused by simulated fast buoyancy ascent escape. The lung contents of TNF-α, IL-1β and IL-6 were at an expression peak at 0.5 hour, although showing no statistical difference when compared with the normal control group. In conclusion, the rat lung expression variations of TNF-α, IL-1β and IL-6 are the most obvious at 0.5 hour within 24 hours after the lung injury by DCS caused by simulated fast buoyancy ascent escape.

Expression changes of inflammatory factors in the rat lung of decompression sickness induced by fast buoyancy ascent escape

Fast buoyancy ascent escape is one of the major naval submarine escape maneuvers. Decompression sickness (DCS) is the major bottleneck to increase the depth of fast buoyancy ascent escape. Rapid decompression induces the release of inflammatory mediators and results in tissue inflammation cascades and a protective anti-inflammatory response. In our previous study, we found that DCS caused by simulated fast buoyancy ascent escape could induce acute lung injury (ALI) and the expression changes of the proinflammatory cytokines: tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β and IL-6 in rat lung tissue. In order to study the expression change characteristics of TNF-α, IL-1β, IL-6, IL-10 and IL-13 in the rat lung of DCS caused by simulated fast buoyancy ascent escape, we detected the rat lung mRNA and protein levels of TNF-α, IL-1β, IL-6, IL-10 and IL-13 at 0.5 hour after DCS caused by simulated fast buoyancy ascent escape (fast escape group), compared with the normal control group (control group) and diving DCS (decompression group). We observed that DCS caused by simulated fast buoyancy ascent escape could increase the mRNA levels of TNF-α, IL-1β, IL-6, IL-10, and the protein levels of TNF-α, IL-10 in rat lung tissue. At the same time, we found that the protein level of IL-13 was also downregulated in rat lung tissue. TNF-α, IL-10 and IL-13 may be involved in the process of the rat lung injury of DCS caused by simulated fast buoyancy ascent escape. In conclusion, the expression changes of inflammatory factors in the rat lung of DCS caused by simulated fast buoyancy ascent escape were probably different from that in the rat lung of diving DCS, which indicated that the pathological mechanism of DCS caused by simulated fast buoyancy ascent escape might be different from that of diving DCS.

Microstructural analysis of Co-Cr dental alloy at the metal-porcelain interface: a pilot study

OBJECTIVE

The purpose of the study was to observe whether conventional porcelain firings had an effect on the underlying microstructure of cobalt-chromium alloys used in porcelain-fused-to-metal systems.

METHODS

One as cast (non-veneered) and two porcelain veneered Co-Cr specimens layered with and without tungsten(W)-metal conditioner were manufactured and analysed. Electron backscatter diffraction was used to determine the crystal structures and grain size across the porcelain-fused-to-metal interface.

RESULTS

No difference was found in the microstructure of the alloy in both with and without W-metal conditioner. For the porcelain fired specimens, disparately sized granular structures were observed adjacent to the metal-porcelain interfaces compared to the bulk of the metal. Ellipsoid shaped grains at the alloy surface ranged between 1-11 μm in diameter and averaged 2.70 μm (SD: 2.17 μm) for the specimen layered with W-metal conditioner and 2.86 μm (SD: 1.85 μm) for the specimen layered without W-metal conditioner. Grains located in the bulk were > 200 μm with dendritic-like features. The depth of the fine grain structure adjacent to the surface had an average depth of 15 μm. The crystal structure of the surface layer was found to be predominantly hexagonal close-packed whereas the underlying bulk was a mixture of both face-centered cubic and hexagonal close-packed phases. For the as cast specimen, similar large grains of over 200 μm was observed but exhibited no dendritic like features. In addition, no fine grains were observed at the surface region of the as cast alloy.

CONCLUSION

Conventional porcelain firings altered the interfacial and bulk microstructure of the alloy while the presence of the W-metal conditioner had no influence on the underlying alloy microstructure.

P38 activation is more important than ERK activation in lung injury induced by prolonged hyperbaric oxygen

Prolonged exposure to hyperbaric oxygen can cause pulmonary and nerve system toxicity. Although hyperbaric oxygen treatment has been used for a broad spectrum of ailments, the mechanisms of prolonged hyperbaric oxygen-induced lung injury are not fully understood. The purpose of the present work was to investigate the roles of ERK, p38, and caspase-3 in rat lung tissue exposed to hyperbaric oxygen at 2.3 atmospheres absolute (atm abs) for two, six and 10 hours. The results showed that the ERK and p38 were phosphorylated at two hours and reached a peak at six hours into exposure to hyperbaric oxygen. While the phosphorylation level of ERK decreased, p38 remained at a high level of activation at 10 hours. The activation of ERK and p38 was down-regulated when rats were exposed to normoxic hyperbaric nitrogen for 10 hours. However, caspase-3 was activated at six hours and 10 hours into exposure to hyperbaric oxygen. These results demonstrated different changes of activation of ERK and p38 during lung injury induced by prolonged exposure to hyperbaric oxygen. The time course changes of activated caspase-3 were similar to the process of p38 activation upon exposure to hyperbaric oxygen. In this way, activation of p38, not ERK, seems to be a mechanism associated with prolonged hyperbaric oxygen-induced lung injury.

Interferon-alpha enhances excitatory transmission in substantia gelatinosa neurons of rat spinal cord

OBJECTIVE

It has been shown that interferon-α (IFN-α) is synthesized and secreted by macrophages, monocytes, T lymphocytes, glial cells and neurons. IFN-α has been shown to have an antinociceptive effect at the supraspinal level in the nerve system. However, it is unclear how IFN-α is involved in the modulation of nociceptive transmission in the spinal cord.

METHODS

In the present study, IFN-α was used to test the potential functional roles in the nociceptive transmission. Using the whole-cell patch-clamp technique, we examined the effects of IFN-α on substantia gelatinosa (SG) neurons in the dorsal root-attached spinal cord slice prepared from adult rats.

RESULTS

We found that IFN-α increased glutamatergic excitatory postsynaptic currents evoked by the stimulation of either Aδ or C afferent fibers. Further studies showed that IFN-α treatment dose-dependently increased spontaneous excitatory postsynaptic current frequency in SG neurons, while not affecting the amplitude. Moreover, intrathecal antibody of IFN-α could reduce nociceptive responses in formalin test.

CONCLUSIONS

These results suggest that IFN-α presynaptically facilitates the excitatory synaptic transmission to SG neurons. The nociceptive responses could be inhibited by IFN-α antibody in the formalin test. Thus, IFN-α enhances the nociceptive transmission, which contributes to the behavioral nociceptive responses.

Follistatin-like 1 suppresses sensory afferent transmission by activating Na+,K+-ATPase

Excitatory synaptic transmission is modulated by inhibitory neurotransmitters and neuromodulators. We found that the synaptic transmission of somatic sensory afferents can be rapidly regulated by a presynaptically secreted protein, follistatin-like 1 (FSTL1), which serves as a direct activator of Na(+),K(+)-ATPase (NKA). The FSTL1 protein is highly expressed in small-diameter neurons of the dorsal root ganglion (DRG). It is transported to axon terminals via small translucent vesicles and secreted in both spontaneous and depolarization-induced manners. Biochemical assays showed that FSTL1 binds to the α1 subunit of NKA and elevates NKA activity. Extracellular FSTL1 induced membrane hyperpolarization in cultured cells and inhibited afferent synaptic transmission in spinal cord slices by activating NKA. Genetic deletion of FSTL1 in small DRG neurons of mice resulted in enhanced afferent synaptic transmission and sensory hypersensitivity, which could be reduced by intrathecally applied FSTL1 protein. Thus, FSTL1-dependent activation of NKA regulates the threshold of somatic sensation.

Different activation of ERK1/2 and p38 with hyperbaric oxygen in dorsal root ganglion

Prolonged hyperbaric oxygen exposure causes pulmonary and nervous system toxicity, although hyperbaric oxygen treatment has been used to treat a broad spectrum of ailments. In the current study, animals have been exposed to 100% oxygen at a pressure of 2.3 atmospheres absolute (ATA) for two, six and 10 hours or 0.23 MPa normoxic hyperbaric nitrogen (N2-O2 mixture, oxygen partial pressure = 21 kPa) for 10 hours. Then we investigated whether ERK1/2 and p38 had been activated in the dorsal root ganglion (DRG) by hyperbaric conditions. Using Western blot analysis, we found that the phosphorylation levels of ERK1/2 (phospho-ERK1/2) increased significantly (p < 0.05, n = 3 for each group) in the six-hour treatment of 100% oxygen at a pressure of 2.3 ATA. The phosphorylation levels of p38 (phospho-p38) increased significantly (p < 0.05, n = 3 for each group) in the 10-hour treatment of 100% oxygen at a pressure of 2.3 ATA--which was consistent with time course changes of an apoptosis marker, cleavage caspase-3--while the phospho-p38 decreased in the 10 hours of N2-O2 mixture. These results demonstrate that the ERK1/2 and p38 have been differently activated in the DRG by prolonged hyperbaric oxygen exposure.

Potentiation of excitatory transmission in substantia gelatinosa neurons of rat spinal cord by inhibition of estrogen receptor alpha

Background

It has been shown that estrogen is synthesized in the spinal dorsal horn and plays a role in modulating pain transmission. One of the estrogen receptor (ER) subtypes, estrogen receptor alpha (ERα), is expressed in the spinal laminae I-V, including substantia gelatinosa (SG, lamina II). However, it is unclear how ERs are involved in the modulation of nociceptive transmission.

Results

In the present study, a selective ERα antagonist, methyl-piperidino-pyrazole (MPP), was used to test the potential functional roles of spinal ERα in the nociceptive transmission. Using the whole-cell patch-clamp technique, we examined the effects of MPP on SG neurons in the dorsal root-attached spinal cord slice prepared from adult rats. We found that MPP increased glutamatergic excitatory postsynaptic currents (EPSCs) evoked by the stimulation of either Aδ- or C-afferent fibers. Further studies showed that MPP treatment dose-dependently increased spontaneous EPSCs frequency in SG neurons, while not affecting the amplitude. In addition, the PKC was involved in the MPP-induced enhancement of synaptic transmission.

Conclusions

These results suggest that the selective ERα antagonist MPP pre-synaptically facilitates the excitatory synaptic transmission to SG neurons. The nociceptive transmission evoked by Aδ- and C-fiber stimulation could be potentiated by blocking ERα in the spinal neurons. Thus, the spinal estrogen may negatively regulate the nociceptive transmission through the activation of ERα.

Diffusion tensor imaging in the assessment of normal-appearing brain tissue damage in relapsing neuromyelitis optica

BACKGROUND AND PURPOSE

Normal-appearing brain tissue (NABT) damage was established in multiple sclerosis by histology, MR spectroscopy, magnetization transfer imaging and diffusion tensor imaging (DTI). However, whether this phenomenon can be detected in relapsing neuromyelitis optica (RNMO) remains unclear. The aim of this study was to use DTI to investigate the presence of NABT damage in RNMO patients and its possible mechanism.

METHODS

Conventional MR imaging and DTI scans were performed in 16 patients with RNMO without visible lesions on brain MR imaging and in 16 sex- and age-matched healthy control subjects. Histogram analysis of mean diffusivity (MD) and fractional anisotropy (FA) was performed in the entire brain tissue (BT), white matter (WM), and gray matter (GM). Region of interest (ROI) analysis of MD and FA was also performed in WM regions connected with the spinal white matter tracts or optic nerve (including medulla oblongata, cerebral peduncle, internal capsule, and optic radiation), in corpus callosum without direct connection with them, and in some GM regions.

RESULTS

From histogram analysis, we found the RNMO group had a higher average MD of the BT, WM, and GM, a lower average MD peak height and a higher average MD peak location of the GM, and a higher average FA peak height of the WM than did the control group. From ROI analysis, compared with control subjects, RNMO patients had a higher average MD and a lower average FA in ROIs of WM connected with the spinal white matter tracts or optic nerve and a normal average MD and FA in corpus callosum without direct connection with them. In addition, a high average MD was found in parietal GM in these patients.

CONCLUSIONS

Our findings confirm the presence of abnormal diffusion in brain tissue in patients with RNMO and suggest that secondary degeneration caused by lesions in the spinal cord and optic nerve might be an important mechanism for this abnormality.

Correlations between edema and the immediate and prolonged painful consequences of inflammation: therapeutic implications?

The precise relationship between the degree of pain and the degree of inflammation in the individual remains debated. A quantitative analysis simultaneously applied to the immediate and prolonged painful consequences of inflammation has not yet been done. Thus, the correlations between edema, nociception and hypersensitivity following an inflammatory insult were assessed in rodents. To better understand the therapeutic value of modifying specific aspects of inflammation, the effects of an anti-inflammatory drug were compared to the results. Inbred strains of mice and outbred rats received an intraplantar injection of honeybee venom and the between-group and within-group correlations were calculated for spontaneous nociceptive measures, thermal and mechanical hypersensitivity, and edema and temperature. The effect of indomethacin on the pain and inflammation measures was examined. Edema correlated with spontaneous flinching, licking and lifting of the injected paw (P< or =0.003), and not with thermal or mechanical hypersensitivity. Indomethacin affected edema and spontaneous nociception dose-dependently, and affected hypersensitivity only at the highest dose tested (P< 0.05). These results suggest that edema may contribute only to immediate spontaneous nociceptive responses to an inflammatory insult, and not to the more clinically relevant prolonged hypersensitivity. This analysis represents a method for determining which inflammatory processes are the most promising therapeutic targets against the multiple painful consequences of inflammation.

Evidence for peripherally antinociceptive action of propofol in rats: Behavioral and spinal neuronal responses to subcutaneous bee venom

In the present study, behavioral and in vivo electrophysiological methods were used to examine the peripheral effects of propofol on tonic ongoing pain-related responses produced by subcutaneous bee venom-induced inflammatory pain state. Local administration of 0.5 microg propofol produced significant suppression of the well-established ongoing pain responses in both conscious rats and dorsal horn nociceptive neurons. The locally antinociceptive action of propofol is not caused by systemic effect, because contralateral administration of the same dose of drug did not produce any effect. This result indicates that besides central actions, propofol has peripherally antinociceptive action as well.

Inhibitory effects of spinal propofol on the responses of spinal dorsal horn neurons in normal rats

Spinal dorsal horn neurons play an important role in the processing of sensory information and are also targets of modulation by both endogenous and exogenous drugs. Propofol is an intravenous anesthetic and whether it has direct modulatory actions on sensory neuronal responses of the spinal cord dorsal horn has not been well studied. In the present study, a single dose (0.5 micromol) of propofol dissolved in dimethyl sulfoxide (DMSO) was directly applied onto the dorsal surface of the spinal cord and its effect was evaluated in 25 wide-dynamic-range (WDR) neurons and 10 low-threshold mechanoreceptive (LTM) neurons by using extracellular single unit recording technique in sodium pentobarbital anesthetized rats. Compared with the DMSO treatment, propofol produced a significant inhibition of WDR neuronal activity evoked by both noxious heat (45, 47, 49 or 53 degrees C, 15 s) and mechanical (pinch, 10 s) stimuli applied to their cutaneous receptive fields (cRF) on the ipsilateral hind paw skin. To investigate whether propofol exerts a modulatory effect on non-nociceptive afferent-mediated activity, the responses of WDR or LTM neurons to non-noxious brush and pressure were also evaluated. The non-noxious mechanically-evoked responses of both WDR and LTM neurons were significantly suppressed by propofol. The present results indicate that propofol has direct actions on the dorsal horn neurons of the spinal cord in rats. However, since both non-nociceptive and nociceptive afferent-mediated activity can be suppressed, the spinal effects of propofol are not likely to be specifically associated with anti-nociception.

[CT imaging analysis in 138 cases with orbital fractures]

PURPOSE

To investigate CT findings of orbital fractures in maxillofacial injuries in order to improve clinical diagnostic accuracy.

METHODS

CT findings of 138 cases (145 orbits) with orbital fractures in maxillofacial injuries were analyzed.

RESULTS

In maxillofacial injuries, orbital fractures of medial and posterolateral walls were most common,which often showed multiple walls fractures. In 145 orbital fractures, there were single wall fractures in 51 cases (35.17%), two-wall fractures in 48 cases (33.10%), three-wall fractures in 31 cases (21.38%) and four-wall fractures in 15 cases (10.35%).

CONCLUSIONS

There were complex orbital fracture in maxillofacial injures, CT examination is a very important tool for diagnosis,which should be applied routinely.

Differential Roles of Spinal Protein Kinases C and A in Development of Primary Heat and Mechanical Hypersensitivity Induced by Subcutaneous Bee Venom Chemical Injury in the Rat

It has been demonstrated that subcutaneous injection of bee venom (BV) can produce different types of pain and hypersensitivity including persistent spontaneous nociception (PSN), primary heat and mechanical hypersensitivity (hyperalgesia) and mirror-image heat (MIH) hypersensitivity in an individual animal, and the changes of spinal neurons are likely to be responsible for the production of these pain-related behaviors. In this study, we examined the roles of spinal protein kinase C (PKC) and protein kinase A (PKA) in the BV-induced different types of pain and hypersensitivity in conscious rats. We found that: (1). BV-induced primary heat hypersensitivity could be blocked by intrathecal pre- or posttreatment with a PKC inhibitor, chelerythrine chloride (CH), while a PKA inhibitor, N-(2-[P-bromocinnamylamino]ethyl)-5-isoquinolinesulfonamide hydrochloride (H89), had no effect. (2). BV-induced primary mechanical hypersensitivity could be blocked by pre- or posttreatment with H89, whereas CH had no effect. (3). Both pre- and posttreatment with H89 produced suppressive effects on both induction and maintenance of the BV-induced PSN and MIH hypersensitivity. Based on the present findings, we proposed that spinal PKC might be activated during the central processes of primary heat hypersensitivity, while spinal PKA is likely to be involved in primary mechanical hypersensitivity induced by subcutaneous BV chemical injury. Taken together with our previous report however, spinal PKC and PKA are likely to be simultaneously involved in the central processes of both PSN and MIH hypersensitivity.

Cervical intraepithelial neoplasia is associated with increased polyamine oxidase and diamine oxidase concentrations in cervical mucus

OBJECTIVE

The aim of this study was to establish whether reactive oxygen species, generated during oxidation of amines, catalyzed by polyamine oxidase (PAO) and diamine oxidase (DAO) in cervical secretions may play a role in the etiology of cervical cancer.

METHODS

Cervical mucus was obtained from women attending the gynecological outpatient department: 139 with and 154 without cytological evidence of cervical intraepithelial neoplasia were recruited. The mucus was freeze dried in liquid nitrogen, weighed, and later resuspended for assay of PAO and DAO concentrations using a chemiluminescence method. The two groups were compared by group sequential analysis using PEST3 software.

RESULTS

Patients with a colposcopic diagnosis of a high-grade squamous intraepithelial lesion (SIL) had significantly higher enzyme activities than control cases (L(N)PAO 1.37 (0.37) versus 1.18 (0.35): Student t test: P < 0.001; L(N)DAO 1.37 (0.36) versus 1.15 (0.37): Student t test: P < 0.001).

CONCLUSION

It is probable that this rise in enzyme activity precedes cytological changes and plays some part in the etiology of cervical cancer, as the cells that undergo premalignant change are normally squamous in origin, whereas mucus is a product of columnar epithelium. Higher enzyme activity in patients with SIL than in controls may be a reflection of higher risk of exposure to amine substrates in semen through multiple sexual partners.

Power Doppler imaging and resistance index measurement in the evaluation of acute renal transplant rejection

PURPOSE

This study was designed to test the hypotheses that power Doppler imaging has a predictive value in the assessment of acute renal allograft rejection and that the information garnered from the combination of resistance index (RI) determination and power Doppler imaging has an even greater predictive value in this assessment.

METHODS

Power Doppler images obtained prior to 96 sequential renal allograft biopsies in 92 patients with suspected renal transplant rejection were retrospectively graded for parenchymal vascularity on a scale of 1 to 4: 1, normal, uniform cortical flow; 2, mild peripheral cortical hypoperfusion; 3, vascular pruning in cortex and medulla; and 4, no visible parenchymal flow, with flow seen only in central vessels. Power Doppler grades and RIs for these cases were compared to graft biopsy results.

RESULTS

No statistically significant association was observed between parenchymal vascularity as graded by power Doppler imaging, RI, and the presence of acute transplant rejection.

CONCLUSIONS

Neither grading of vascularity on power Doppler images, RI measurement, nor the combination of these methods is an accurate means of detecting renal allograft rejection.

Adequacy and pitfalls of G6PD deficiency counseling in Hong Kong

Glucose-6-Phosphate-Dehydrogenase (G6PD) deficiency is common in Hong Kong with an incidence of 4.5% in male and 0.36% in female (Lo et al. 1996).The Neonatal Screening Unit of Clinical Genetic Service started its territory-wide neonatal screening program for G6PD deficiency and congenital hypothyroidism in 1984 (Lam et al, 1986). Because of insufficient manpower and resource, we have been giving health counseling on the phone to parents of G6PD deficient babies and then refer them to nearby maternal and child health centres for monitoring of jaundice. The disease, mode of inheritance, recurrence risk and the precaution against certain medicines (Chan 1996) and chemicals are explained. The purpose (Lam, 1994) is to reassure the parents that their G6PD deficient babies can be as normal as everyone and that they can have normal life. Nevertheless, it has not been established whether telephone counseling has any effect on the affected family in the form of psychological trauma (Marteau, 1989; Fyro, 1987; Li et al, 1996) or significant influence on the decision on future reproduction. This study tried to evaluate the service from the parents' point of view by 1) gathering information on parents' awareness and perception of G6PD deficiency, 2) determination of parents' attitude towards the telephone counseling, and 3) finding out the effect of G6PD deficiency on parents' decision on future reproduction. Over 300 parents were contacted by telephone, and were asked to respond to questions on a questionnaire . The telephone interview focused on parents' understanding of G6PD deficiency, their attitude towards this disease and the possible effect on future reproduction decision. Results showed that over 90% of cases that we had counseled attended the maternal and child health centres. Most of them accepted the presence of G6PD deficiency in their family which did not affect their decision on future pregnancy. Telephone counseling failed to establish a helping relationship with the parent as face to face counseling was more personal. The findings revealed that though telephone counseling had its shortcoming it served the target group effectively. Telephone counseling is still the method of choice for the G6PD deficiency counseling in this locality.

Validation of in vivo MR measurement of oxygen saturation after resuscitation with a hemoglobin-based oxygen carrier in a rabbit model

RATIONALE AND OBJECTIVES

The authors tested whether noninvasive magnetic resonance (MR) oximetry is accurate in the in vivo measurement of oxygen saturation in a stroma-free, hemoglobin-based oxygen carrier (HBOC).

MATERIALS AND METHODS

A central venous catheter was placed in the inferior vena cava (IVC) of 10 New Zealand white rabbits (weight range, 2.5-3.2 kg). Each rabbit underwent removal of 20% of blood volume followed by resuscitation with 10 mL/kg of bovine HBOC-200. Oxygen saturation of the blood mixture was measured in vivo at the IVC with MR oximetry, with separate in vitro calibration for each animal. Blood drawn from the IVC was measured with ex vivo oximetry, which was used as the standard of reference. The in vivo and ex vivo measurements were compared.

RESULTS

There was no significant difference (P > .1) between measurements obtained with MR oximetry and ex vivo oximetry. The results with in vivo MR oximetry demonstrated excellent correlation with those from ex vivo oximetry (r = 0.99) over a wide range of physiologic oxygen saturation values (16.7%-74.9%) in venous blood.

CONCLUSION

Noninvasive in vivo MR measurement of oxygen saturation is valid for whole blood mixed with stroma-free hemoglobin. Therefore, MR oximetry may be clinically useful for assessing the oxygenation status in patients resuscitated with a HBOC.