Effect of the age and sex on growth performance and feather quality of 13 to 25-weeks-old White Roman geese

This study aimed to determine the effect of age and sex in weeks on growth, carcass performances, and feather quality of White Roman geese and analyze the relative effect of age and sex in weeks on feather characteristics in geese. In animal experiments, 120 White Roman geese aged 13 wk were randomly distributed among 12 pens and fed grower diet ad libitum during the growing period, with each pen containing 10 males or 10 females, depending on a completely random design. Ten geese each in their 13, 15, 17, 19, 21, 23, and 25 wk of age were sacrificed. The results showed that the age had no significant effect on the body weight (BW) of geese (P > 0.05). The chest girth was significantly longer in 21 to 25 wk old than in 13- to 19-wk-old geese (P < 0.05). The results reveal no significant change in carcass weight of grower geese among 13- to 25-wk age groups (P > 0.05). The down percentage of the 25-wk-old age group was significantly higher than that of the 13-, 15-, and 17-wk age groups (P < 0.05). The male geese had a higher dry feather weight than the females (P < 0.05). Similarly, the 18-h feed-deprived body weight (18-h FDBW) and 4 to 10 cm feather weight were significantly negatively correlated in grower geese (-0.42). This provides the feather industry an opportunity for the better utilization of grower geese by-products. In conclusion, the age has no influence on BW among 13- to 25-wk-old geese, and a good down percentage and dry weight were observed at 25 wk of age. The 18-h FDBW and down percentage had a significantly negative correlation (-0.55) in grower geese.

Patterning and doping of transition metals in tungsten dichalcogenides

Substitutional transition metal doping in two-dimensional (2D) layered dichalcogenides is of fundamental importance in manipulating their electrical, excitonic, magnetic, and catalytic properties through the variation of the d-electron population. Yet, most doping strategies are spatially global, with dopants embedded concurrently during the synthesis. Here, we report an area-selective doping scheme for W-based dichalcogenide single layers, in which pre-patterned graphene is used as a reaction mask in the high-temperature substitution of the W sublattice. The chemical inertness of the thin graphene layer can effectively differentiate the spatial doping reaction, allowing for local manipulation of the host 2D materials. Using graphene as a mask is also beneficial in the sense that it also acts as an insertion layer between the contact metal and the doped channel, capable of depinning the Fermi level for low contact resistivity. Tracing doping by means of chalcogen labelling, deliberate Cr embedment is found to become energetically favorable in the presence of chalcogen deficiency, assisting the substitution of the W sublattice in the devised chemical vapor doping scheme. Atomic characterization using scanning transmission electron microscopy (STEM) shows that the dopant concentration is controllable and varies linearly with the reaction time in the current doping approach. Using the same method, other transition metal atoms such as Mo, V, and Fe can also be doped in the patterned area.

Serotonin modulation in the male Aedes aegypti ear influences hearing

Male Aedes aegypti (Ae. aegypti) mosquitoes rely on hearing to identify conspecific females for mating, with the male attraction to the sound of flying females (“phonotaxis”) an important behavior in the initial courtship stage. Hearing thus represents a promising target for novel methods of mosquito control, and hearing behaviors (such as male phonotaxis) can be targeted via the use of sound traps. These traps unfortunately have proven to be relatively ineffective during field deployment. Shifting the target from hearing behavior to hearing function could therefore offer a novel method of interfering with Ae. aegypti mating. Numerous neurotransmitters, including serotonin (5-hydroxytryptamine, or 5-HT) and octopamine, are expressed in the male ear, with modulation of the latter proven to influence the mechanical responses of the ear to sound. The effect of serotonin modulation however remains underexplored despite its significant role in determining many key behaviors and biological processes of animals. Here we investigated the influence of serotonin on the Ae. aegypti hearing function and behaviors. Using immunohistochemistry, we found significant expression of serotonin in the male and female Ae. aegypti ears. In the male ear, presynaptic sites identified via antibody labelling showed only partial overlap with serotonin. Next, we used RT-qPCR to identify and quantify the expression levels of three different serotonin receptor families (5-HT1, 5-HT2, and 5-HT7) in the mosquito heads and ears. Although all receptors were identified in the ears of both sexes, those from the 5-HT7 family were significantly more expressed in the ears relative to the heads. We then thoracically injected serotonin-related compounds into the mosquitoes and found a significant, reversible effect of serotonin exposure on the male ear mechanical tuning frequency. Finally, oral administration of a serotonin-synthesis inhibitor altered male phonotaxis. The mosquito serotonergic system and its receptors thus represent interesting targets for novel methods of mosquito, and thus disease, control.

Effects of dietary supplementation with Taiwanese tea byproducts and probiotics on growth performance, lipid metabolism, and the immune response in red feather native chickens

Objective

This study compared the catechin composition of different tea byproducts and investigated the effects of dietary supplementation with green tea byproducts on the accumulation of abdominal fat, the modulation of lipid metabolism, and the inflammatory response in red feather native chickens.

Methods

Bioactive compounds were detected, and in vitro anti-obesity capacity analyzed via 3T3-L1 preadipocytes. In animal experiments, 320 one-day-old red feather native chickens were divided into 4 treatment groups: control, basal diet supplemented with 0.5% Jinxuan byproduct (JBP), basal diet supplemented with 1% JBP, or basal diet supplemented with 5×10⁶ colony-forming unit (CFU)/kg Bacillus amyloliquefaciens+5×10⁶ CFU/kg Saccharomyces cerevisiae (BA+SC). Growth performance, serum characteristics, carcass characteristics, and the mRNA expression of selected genes were measured.

Results

This study compared several cultivars of tea, but Jinxuan showed the highest levels of the anti-obesity compound epigallocatechin gallate. 3T3-L1 preadipocytes treated with Jinxuan extract significantly reduced lipid accumulation. There were no significant differences in growth performance, serum characteristics, or carcass characteristics among the groups. However, in the 0.5% JBP group, mRNA expression of fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) were significantly decreased. In the 1% JBP group, FAS, ACC and peroxisome proliferator-activated receptor γ levels were significantly decreased. Moreover, inflammation-related mRNA expression levels were decreased by the addition of JBP.

Conclusion

JBP contained abundant catechins and related bioactive compounds, which reduced lipid accumulation in 3T3-L1 preadipocytes, however there was no significant reduction in abdominal fat. This may be due to a lack of active anti-obesity compounds or because the major changes in fat metabolism were not in the abdomen. Nonetheless, lipogenesis-related and inflammation-related mRNA expression were reduced in the 1% JBP group. In addition, dietary supplementation with tea byproducts could reduce the massive amount of byproducts created during tea production and modulate lipid metabolism and the inflammatory response in chickens.

Laetiporus sulphureus-fermented wheat bran enhanced the broiler growth performance by improving the intestinal microflora and inflammation status

This study investigates the effects of Laetiporus sulphureus–fermented wheat bran (LS) as a feed supplementation on the immunomodulative properties in broiler chickens. Crude phenolic compounds, crude polysaccharides, crude triterpenoids, and ergosterol were determined in LS water extracts. In animal experiments, 400 male broilers (Ross 308) were randomly assigned into 5 groups fed with a corn–soybean–based diet (control) and a control diet replaced with 5% wheat bran (WB), 10% WB, 5% LS, and 10% LS, respectively. Each group had 4 replicates and 20 birds per pen (total of 80 birds/treatment). The results showed that the 5% LS–supplemented group had significantly higher BW in the finisher phase (22–35 D). Better feed conversion ratio (P < 0.05) of LS-supplemented groups was observed in both the finisher phase and the overall experimental period. The LS-supplemented groups had significantly lower coliform counts in the ileum than the other treatment and control groups (P < 0.05). The results of serum immunoglobulin showed that LS supplementation significantly increased serum IgA concentration compared with the control and WB-supplemented groups (P < 0.05). Simultaneously, ileal IgA contents of the LS groups were significantly higher than in the WB and control groups (P < 0.05). Regarding proinflammatory cytokines, serum tumor necrosis factor alpha and IL-6 in the LS-supplemented groups were significantly lower than those in the 10% WB group (P < 0.05), whereas serum tumor necrosis factor alpha and IL-1β in the 5% LS group were significantly lower than in both the control and WB-supplemented groups (P < 0.05). An investigation on the effects of LS on immune-related genes in broiler showed that chickens supplemented with 5% LS had lower levels of liver and jejunum IL-1β and NF-κB mRNA compared with the control group and WB groups (P < 0.05). In conclusion, LS supplementation can potentially enhance growth performance of broilers by improving intestinal microflora and inflammation status.

Effects of mushroom waster medium and stalk residues on the growth performance and oxidative status in broilers

OBJECTIVE

The study developed mushroom stalk residues as feed additives in the broiler diet for improving the growth performance and immunity of broilers as well as to increase the value of mushroom stalk residues.

METHODS

In total, 300 ROSS 308 broilers were randomly allocated into fifteen pens with five dietary treatments: i) control, basal diet; ii) CMWM, supplemented with 1% Cordyceps militaris waster medium (CM); iii) CMPE, supplemented with 0.5% CM+0.5% Pleurotus eryngii stalk residue (PE); iv) CMPS, supplemented with 0.5% CM+0.5% Pleurotus sajorcaju stalk residue (PS); v) CMFV, supplemented with 0.5% CM+0.5% Fammulina velutipes stalk residue (FV).

RESULTS

The chemical analysis results showed that CM extracts, PE extracts, PS extracts, and FV extracts contain functional components such as polysaccharides and phenols and have both 2, 2-diphenyl-1-picryl-hydrazyl-hydrate scavenging and Ferrous scavenging capacities. The group CMWM saw increased body weight gain and feed conversion rate and the promotion of jejunum villus growth, but there is no significant difference in the intestinal bacteria phase. Antioxidant genes in the nuclear factor (erythroid-derived 2)-like 2 (Nrf2)- antioxidant responsive element pathway among the groups are significantly higher than that of the control group, especially in group CMWM.

CONCLUSION

The mushroom stalk residues have antioxidant functional components, can improve the intestinal health and body weight gain of chickens, and can activate the antioxidant pathway of Nrf2 to increase the heme oxygenase-1 expression. The treatment with 1% CM was the most promising as a feed additive.

Effects of dietary Antrodia cinnamomea fermented product supplementation on antioxidation, anti-inflammation, and lipid metabolism in broiler chickens

Objective

This study was investigated the effects of dietary supplementation of Antrodia cinnamomea fermented product on modulation of antioxidation, anti-inflammation, and lipid metabolism in broilers.

Methods

Functional compounds and in vitro antioxidant capacity were detected in wheat bran (WB) solid-state fermented by Antrodia cinnamomea for 16 days (FAC). In animal experiment, 400 d-old broiler chickens were allotted into 5 groups fed control diet, and control diet replaced with 5% WB, 10% WB, 5% FAC, and 10% FAC respectively. Growth performance, intestinal microflora, serum antioxidant enzymes and fatty acid profiles in pectoral superficial muscle were measured.

Results

Pretreatment with hot water extracted fermented product significantly reduced chicken peripheral blood mononuclear cells death induced by lipopolysaccharide and 2,2′-Azobis(2-amidinopropane) dihydrochloride. Birds received 5% and 10% FAC had higher weight gain than WB groups. Cecal coliform and lactic acid bacteria were diminished and increased respectively while diet replaced with FAC. For FAC supplemented groups, superoxide dismutase (SOD) activity increased at 35 days only, with catalase elevated at 21 and 35 day. Regarding serum lipid parameters, 10% FAC replacement significantly reduced triglyceride and low-density lipoprotein level in chickens. For fatty acid composition in pectoral superficial muscle of 35-d-old chickens, 5% and 10% FAC inclusion had birds with significantly lower saturated fatty acids as compared with 10% WB group. Birds on the 5% FAC diet had a higher degree of unsaturation, followed by 10% FAC, control, 5% WB, and 10% WB.

Conclusion

In conclusion, desirable intestinal microflora in chickens obtaining FAC may be attributed to the functional metabolites detected in final fermented product. Moreover, antioxidant effects observed in FAC were plausibly exerted in terms of improved antioxidant enzymes activities, increased unsaturated degree of fatty acids in chicken muscle and better weight gain in FAC inclusion groups, indicating that FAC possesses promising favorable mechanisms worthy to be developed.

Effects of dietary Antrodia cinnamomea fermented product supplementation on metabolism pathways of antioxidant, inflammatory, and lipid metabolism pathways-a potential crosstalk

Objective

This study was conducted to fathom the underlying mechanisms of nutrition intervention and redox sensitive transcription factors regulated by Antrodia cinnamomea fermented product (FAC) dietary supplementation in broiler chickens.

Methods

Four hundreds d-old broilers (41±0.5 g/bird) assigned to 5 groups were examined after consuming control diet, or control diet replaced with 5% wheat bran (WB), 10% WB, 5% FAC, and 10% FAC. Liver mRNA expression of antioxidant, inflammatory and lipid metabolism pathways were analyzed. Prostaglandin E2 (PGE₂) concentration in each group were tested in the chicken peripheral blood mononuclear cells (cPBMCs) of 35-d old broilers to represent the stress level of the chickens. Furthermore, these cells were stimulated with 2,2′-Azobis(2-amidinopropane) dihydrochloride (AAPH) and lipopolysaccharide (LPS) to evaluate the cell stress tolerance by measuring cell viability and oxidative species.

Results

Heme oxygenase-1, glutathione S-transferase, glutamate-cysteine ligase, catalytic subunit, and superoxide dismutase, and nuclear factor (erythroid-derived 2)-like 2 (Nrf2) that regulates the above antioxidant genes were all up-regulated significantly in FAC groups. Reactive oxygen species modulator protein 1 and NADPH oxygenase 1 were both rather down-regulated in 10% FAC group as comparison with two WB groups. Despite expressing higher level than control group, birds receiving diet containing FAC had significantly lower expression level in nuclear factor-kappa B (NF-κB) and other genes (inducible nitric oxide synthase, tumor necrosis factor-α, interleukin-1β, nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3, and cyclooxygenase 2) involving in inflammatory pathways. Additionally, except for 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase that showed relatively higher in both groups, the WB, lipoprotein lipase, Acetyl-CoA carboxylase, fatty acid synthase, fatty acid binding protein, fatty acid desaturase 2 and peroxisome proliferator-activated receptor alpha genes were expressed at higher levels in 10% FAC group. In support of above results, promoted Nrf2 and inhibited NF-κB nuclear translocation in chicken liver were found in FAC containing groups. H₂O₂ and NO levels induced by LPS and AAPH in cPBMCs were compromised in FAC containing diet. In 35-d-old birds, PGE₂ production in cPBMCs was also suppressed by the FAC diet.

Conclusion

FAC may promote Nrf2 antioxidant pathway and positively regulate lipid metabolism, both are potential inhibitor of NF-κB inflammatory pathway.

Potential crosstalk of oxidative stress and immune response in poultry through phytochemicals - A review

Phytochemicals which exist in various plants and fungi are non-nutritive compounds that exert numerous beneficial bioactive actions for animals. In recent years following the restriction of antibiotics, phytochemicals have been regarded as a primal selection when dealing with the challenges during the producing process in the poultry industry. The selected fast-growing broiler breed was more fragile when confronting the stressors in their growing environments. The disruption of oxidative balance that impairs the production performance in birds may somehow be linked to the immune system since oxidative stress and inflammatory damage are multi-stage processes. This review firstly discusses the individual influence of oxidative stress and inflammation on the poultry industry. Next, studies related to the application of phytochemicals or botanical compounds with the significance of their antioxidant and immunomodulatory abilities are reviewed. Furthermore, we bring up nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and nuclear factor kappa B (NF-κB) for they are respectively the key transcription factors involved in oxidative stress and inflammation for elucidating the underlying signal transduction pathways. Finally, by the discussion about several reports using phytochemicals to regulate these transcription factors leading to the improvement of oxidative status, heme oxygenase-1 gene is found crucial for Nrf2-mediated NF-κB inhibition.

Effects of mulberry leaves on production performance and the potential modulation of antioxidative status in laying hens

This study evaluated the antioxidant ability of Taisung No. 3 mulberry leaf extract (MLE) as well as the potential of mulberry leaf (ML)-based dietary supplementation for modulating the antioxidative status of laying hens. The results showed that the MLE had a total phenolic compound content of 7.4 ± 0.15 mg of gallic acid equivalent/g dry weight (DW) and a total flavonoid content of 4.4 ± 0.19 mg of quercetin equivalent/g DW. The 2, 2-diphenyl-1-picrylhydrazyl free-radical-scavenging ability was 45.9% when 0.1 mg/mL MLE was added. The lipid oxidation inhibition ability was 43.9% when 50 mg/mL MLE was added. We subjected 96 laying hens (Hendrix Genetics) to 4 treatments, namely diets supplemented with dry ML at 0 (control), 0.5, 1, or 2% for 12 weeks. Each treatment involved 8 replicates with 3 hens each. The results indicated that the 0.5% ML-supplemented group exhibited significantly higher mRNA levels of antioxidant-regulated genes, such as Nrf2, HO-1, and GST, and significantly lower ROMO1 gene expression levels at wk 12. The serum malondialdehyde level was lower and the catalase activity and superoxide dismutase activity were higher in all the ML-supplemented groups than in the control group. The egg mass and feed conversion rate significantly improved in the ML-supplemented groups compared with the control group, and, overall, 1% ML supplementation had the most favorable effects at one to 12 weeks. The egg yolk weight, shell weight, shell strength, shell thickness, yolk color, and Haugh unit were increased among all ML-supplemented groups at one to 12 weeks. On the basis of these observations, we conclude that 0.5% ML can be used as a new feed additive to potentially modulate the antioxidative status of laying hens and improve their production performance and egg quality.

Antioxidant capacity of phytochemicals and their potential effects on oxidative status in animals - A review

Oxidative stress suppresses animal health, performance, and production, subsequently impacting economic feasibility; hence, maintaining and improving oxidative status especially through natural nutrition strategy are essential for normal physiological process in animals. Phytochemicals are naturally occurring antioxidants that could be considered as one of the most promising materials used in animal diets in various forms. In this review, their antioxidant effects on animals are discussed as reflected by improved apparent performance, productivity, and the internal physiological changes. Moreover, the antioxidant actions toward animals further describe a molecular basis to elucidate their underlying mechanisms targeting signal transduction pathways, especially through the antioxidant response element/nuclear factor (erythroid-derived 2)-like 2 transcription system.

Effects of co-fermented Pleurotus eryngii stalk residues and soybean hulls by Aureobasidium pullulans on performance and intestinal morphology in broiler chickens

Soybean hulls are a by-product of soybean processing for oil and meal production; Pleurotus eryngii stalk residues (PESR) are by-products of the edible portion of the fruiting body enriched in bioactive metabolites. This study evaluated the effects of co-fermented PESR and soybean hulls with Aureobasidium pullulans on performance and intestinal morphology in broiler chickens. The in vitro experimental results showed that xylananse and mannanase activity of solid-state fermented soybean hulls (100% SBH) and soybean hulls partially replaced with PESR (75:25, SHP) reached peak at day 12; solid-state fermentation (SSF) enhanced the total phenolic content and trolox equivalency in both products as well. Additionally, FSHP had higher xylotriose and mannobiose levels than fermented FSBH did. A total of 400 broilers (Ross 308) were assigned randomly into four groups receiving the basal diet (control) or the basal diet supplemented with 0.5% fermented SBH (0.5% FSBH), 0.5% fermented SBHP (0.5% FSHP) and 1.0% fermented SBHP (1.0% FSHP) until 35 d of age, respectively. Results demonstrated that 0.5% FSHP addition increased body weight gain as compared with corresponding normal diet fed control in birds during entire experimental period. Compared with the control group, 0.5% FSHP group significantly increased the ratio of lactic acid bacteria to Clostridium perfringens in ceca as well as ileum villus height and jejunum villus height/crypt depth ratio of 35 d old birds. In conclusion, 0.5% FSHP supplementation in the diet could obtain not only improved body weight gain, but optimal intestinal morphology by exerting its bioactive metabolite properties when fed to broilers.

Effects of dietary garlic scape meal on the growth and meat characteristics of geese

This study evaluated the growth performance and meat characteristics of grower geese whose diets included garlic scape meal (GSM), a by-product of garlic production. Scape is the leaf-less flower stem of garlic. Garlic scape (GS) extracts contained 84.7 ± 3.8 μg/g dry weight (DW), 81.4 ± 8.2 μg/g DW, 0.78 ± 0.05 mg gallic acid equivalent/g DW and 31.67 ± 2.25 μg/g DW of allicin, alliin, total phenolics and flavonoid contents, respectively. In total, 120 White Roman geese aged 5 weeks were randomly distributed among 12 pens and fed on a grower diet ad libitum during the growth period. Employing a completely random design, 5 males and 5 females were placed in each pen. Each treatment was applied to three pens (in total 30 birds) and the treatments comprised the following: 1) control (maize-soybean meal), 2) 5% of maize replaced with 5% of GSM (5% GSM), 3) 10% of maize replaced with 10% of GSM (10% GSM) and 4) 15% of maize replaced with 15% of GSM (15% GSM). Each group of 30 birds was treated for 8 weeks. The results revealed that the 15% GSM group was characterised by a lower feed conversion ratio than the control group; however, these groups did not differ significantly in their body weights (BWs). In addition, the 10% GSM group did not differ in both the feed conversion ratio and consumption. The flavour intensity score of meats in the 10% GSM group was significantly lower than those of meats in the 5% GSM and control groups. The general acceptability scores of meats in the 5% GSM and control groups were higher than those of meat in the 10% GSM group. The study concluded that 5% dietary GSM in the feed did not adversely affect the growth performance, meat characteristics or sensory evaluation of grower geese. Hence, the environment can be protected by including agricultural waste in goose diets.

Effects of supplemental glutamine on growth performance, plasma parameters and LPS-induced immune response of weaned barrows after castration

Two experiments were conducted to investigate the effects of supplemental glutamine on growth performance, plasma parameters and LPS-induced immune response of weaned barrows after castration. In experiment 1, forty-eight weaned male piglets were used and fed maize and soybean meal diets supplemented with 0 (Control) or 2% L-Gln (Gln+) for 25 days. The results indicated that the Gln+ group tended to increase average daily gain compared to control in stages of days 7 to 14 and 0 to 25. The Gln+ had significantly better feed efficiency than the control group did during days 14 to 25 and 0 to 25. The plasma blood urea nitrogen and alkaline phosphatase contents of Gln+ group were higher than those of the control group on day 14 post-weaning. In experiment 2, sixteen weaned male piglets were injected with E. coli K88+ lipopolysaccharide (LPS) on day 14 post-weaning. The results showed that the Gln+ group had lower concentrations of plasma adrenocorticotrophic hormone and cortisol than the control group on day 14 pre-LPS challenge. In addition, Gln+ group had higher plasma IgG concentration than the control group for pre- or post-LPS challenged on day 14 post-weaning. In summary, dietary supplementation of Gln was able to alleviate the stressful condition and inflammation associated with castration in weaned barrows, and to improve their immunity and growth performance in the early starter stage.

Effects of dietary supplementation of Chinese medicinal herbs on polymorphonuclear neutrophil immune activity and small intestinal morphology in weanling pigs

The purpose of this study was to evaluate the effects of dietary Chinese medicinal herbs (CMH) supplementation composed of Panax ginseng, Dioscoreaceae opposite, Atractylodes macrocephala, Glycyrrhiza uralensis, Ziziphus jujube and Platycodon grandiflorum, on the performance, intestinal tract morphology and immune activity in weanling pigs. Two hundred and forty weaned pigs were assigned randomly to four dietary groups including the negative control (basal diet), 0.1% CMH, 0.3% CMH and 0.114% antibiotic (Chlortetracycline calcium Complex, Sulfathiazole and Procaine Penicillin G) supplementation groups for a 28-day feeding trial. Results indicated that both CMH supplementation groups had a better gain and feed/gain than control group (CT) during the first 2 weeks of the experimental period. The 0.3% CMH had a significant decrease in the diarrhoea score in first 10 days of experimental period when compared with other groups. The CMH supplementation groups had a higher villous height, increased lactobacilli counts in digesta of ileum and decreased coliform counts in colon compared with CT. The immune activities of polymorphonuclear leucocytes (PMNs), including the respiratory burst and Salmonella-killing ability, were significantly enhanced in CMH supplementation groups at day 7 of experiment period. The CMH and antibiotic supplementations increased the nutrient digestibility such as dietary dry matter, crude protein and gross energy in weanling pigs. In conclusion, the dietary CMH supplementation improved intestinal morphology and immune activities of PMNs, thus giving rise to nutrient digestibility and reduce diarrhoea frequency in weanling pigs.

Advances in distributed parameter approach to the dynamics and control of activated sludge processes for wastewater treatment

This paper presents a review of modelling and control of biological nutrient removal (BNR)-activated sludge processes for wastewater treatment using distributed parameter models described by partial differential equations (PDE). Numerical methods for solution to the BNR-activated sludge process dynamics are reviewed and these include method of lines, global orthogonal collocation and orthogonal collocation on finite elements. Fundamental techniques and conceptual advances of the distributed parameter approach to the dynamics and control of activated sludge processes are briefly described. A critical analysis on the advantages of the distributed parameter approach over the conventional modelling strategy in this paper shows that the activated sludge process is more adequately described by the former and the method is recommended for application to the wastewater industry.

Surgical treatment of post-traumatic myelopathy associated with syringomyelia

STUDY DESIGN

Retrospective review.

OBJECTIVE

Evaluate the clinical outcome of surgical intervention for post-traumatic syringomyelia.

INTRODUCTION

Progressive post-traumatic cystic myelopathy (PPCM), or syringomyelia, can occur after spinal cord injury. The authors present their surgical treatment protocol and treatment outcome of a series of patients with post-traumatic syringomyelia.

METHODS

The medical records of 53 patients with PPCM undergoing surgical treatment were reviewed. Laminectomies and intraoperative ultrasonography were performed. For patients with no focal tethering and only a confluent cyst on ultrasonography, a syringosubarachnoid shunt (stent) was inserted. For patients with both tethering and a confluent cord cyst, an untethering procedure was performed first. When a cyst showed significant size reduction (>50%) after untethering, no shunt was placed. When the cyst size persisted on ultrasonographic images, a short syringosubarachnoid shunt was used. The mean follow-up was 23.9 months for the 45 patients available for follow-up (range 12-102 months).

RESULTS

The interval between the causative event and the operation was from 5 months to 37 years (mean 6.5 years). Pain was the most frequent manifestation, followed by motor deterioration and spasticity. Postoperative improvements in >50% of the patients were noted in those presenting with worsening motor function or spasticity. In 19 of 28 patients with associated tethered spinal cord, untethering alone caused significant collapse of the cyst. Postoperative MRI demonstrated cyst collapse in 95% of the patients with untethering alone and 93% of the patients with a syringosubarachnoid shunt.

CONCLUSION

Post-traumatic syringomyelia can occur with or without cord tethering. Untethering alone for patients with cord tethering and cyst formation can reduce cyst size and alleviate the symptoms and signs of syringomyelia in the majority of these cases. Untethering with expansion of subarachnoid space with an expansile duraplasty may be a more physiologic way of treating a tethered cord with associated syringomyelia, i.e., treating the cause rather than the result.

p53 and p21 expression in precancerous lesions and carcinomas of the uterine cervix: overexpression of p53 predicts poor disease outcome

OBJECTIVES

Abnormal expression of the p53 and p21(waf1/cip1) tumor suppressor genes has been observed in a variety of human tumors, but little is known about its expression during cervical tumorigenesis. To identify the potential implications of both genes in the development of cervical carcinoma and explore the clinical importance of changes in gene expression, we assessed the levels of both proteins in precancerous lesions and carcinomas of the cervix.

METHODS

In our study, 10 low-grade squamous intraepithelial lesions (LSIL), 35 high-grade squamous intraepithelial lesions (HSIL), 12 microinvasive carcinomas, and 103 invasive carcinomas were evaluated. The expression of p53 and p21 was studied by immunohistochemistry using monoclonal antibodies specific for these proteins.

RESULTS

p21 was expressed in all samples of normal epithelium, LSIL, and HSIL, and the mean values of expression were 50.3, 42.5, and 44.5%, respectively. Conversely, the expression of p21 was significantly reduced in microinvasive (30.7%) and invasive carcinomas (9.9%). p53 nuclear staining was not detected in normal epithelium samples or LSILs, while 4 (11.4%) of 35 HSILs, 1 (8.3%) of 12 microinvasive carcinomas, and 38 (36.9%) of 103 invasive carcinomas were positive for p53. Compared with the results of the control group, precancerous lesions, and microinvasive carcinoma, the mean value of p53 expression (4.8%) in invasive carcinoma was significantly higher. Furthermore, p53 overexpression was significantly associated with advanced stage of the tumor (P < 0.001) [16/67 (23.9%) stage I, 15/28 (53.6%) stage II, and 7/8 (87.5%) stage III/IV]. In univariate analysis, p53 overexpression was a significant predictor of poor survival, whereas it had no independent influence on overall survival using the Cox regression method. Our data also revealed that no association between p53 immunostaining and p21 expression was found.

CONCLUSIONS

The trend of reduced p21 expression in microinvasive and invasive carcinomas suggests that p21 may play a tumor-suppressor function in neoplastic transformation in cervical epithelium and inactivation of p21 may be an early event in cervical carcinogenesis. Our results indicated that p53 overexpression was a significant predictor of poor disease outcome in univariate analysis. Moreover, significantly increased expression of p53 in advanced-stage cervical carcinoma implies that inactivation of p53 is associated with tumor progression. Finally, this study further supports the notion that induction of p21 expression can be regulated in a p53-independent manner.

Toxicity following high-dose three-dimensional conformal and intensity-modulated radiation therapy for clinically localized prostate cancer

OBJECTIVES

To report the toxicity profile of patients treated with three-dimensional conformal radiation therapy (3D-CRT) or intensity-modulated radiation therapy (IMRT) receiving doses of 82 Gy or more to portions of their prostate.

METHODS

Forty-four patients treated with radiation therapy for prostate cancer between June 1992 and August 1998 at the University of California, San Francisco received a maximal dose within the target volume (Dmax) of 82 Gy or more. Eighteen patients were boosted selectively to a limited portion of their prostate using IMRT, whereas 26 patients were treated with 3D-CRT and had unselected "hot spots" within their prostate. The Radiation Therapy Oncology Group (RTOG) acute and late toxicity scales were used to score gastrointestinal (GI) and genitourinary (GU) morbidity.

RESULTS

Median follow-up and Dmax were 23.1 months (range 10.0 to 84.7) and 84.5 Gy (range 82.0 to 96.7), respectively. Of the patients, 59.1% and 34.1% developed some level of acute GU and GI toxicity, respectively. One patient experienced grade 3 acute GI toxicity. No other grade 3 or greater acute toxicity was observed. The 2-year actuarial rates for freedom from late GI and GU morbidity were 77.1% (95% confidence interval [CI] 60.4% to 87.5%) and 79.5% (95% CI 62.7% to 89.3%), respectively. Although no grade 3 or greater late GU morbidity has been observed to date, 3 patients experienced grade 3 late GI morbidity. However, these cases involved rectal bleeding and were effectively managed with laser coagulation/fulguration.

CONCLUSIONS

Doses of 82 Gy or more to a portion of the prostate gland can be tolerated with acceptable morbidity. This observation supports the continued investigation of IMRT as a means for improving disease control in prostate cancer.

Expression of functional beta 2-adrenergic receptors in a rat airway epithelial cell line (SPOC1) and cell density-dependent induction by glucocorticoids

The beta 2-adrenergic receptor (beta 2AR) signal transduction system regulates many key functions of airway epithelium. In this study, we have pharmacologically characterized the beta 2AR and determined the impact of glucocorticoids on beta 2AR gene transcription in SPOC1 cells, a continuous cell line derived from the tracheal epithelium of rats. [125I]Cyanoiodopindolol assays demonstrated that binding to SPOC1 cell membranes was saturable (Bmax = 62.6 +/- 6 fmol/mg protein) and of high affinity (Kd = 6.3 +/- 0.8 pM). From competition experiments, the rank order of potency of agonists (isoproterenol > epinephrine >> norepinephrine) and the high affinity (Ki = 0.37 +/- 0.05 nM) of the beta 2-selective antagonist ICI 118,551 suggested the predominance of the beta 2AR subtype. Two isoforms of the alpha subunit of Gs (45 and 52 kDa) were identified by Western blot analysis. Isoproterenol-stimulated cyclic AMP levels increased in a dose-dependent manner, confirming that SPOC1 cell beta 2ARs are functionally coupled to adenylyl cyclase. The effect of glucocorticoids on beta 2AR expression was assessed in radioligand and transient transfection assays. Dexamethasone treatment of SPOC1 cells increased both beta 2AR protein and beta 2AR-luciferase fusion gene expression 1.6- to 3.1-fold, with the greatest increase demonstrated in cells cultured at low density compared to cells grown at high density.

The significance of functioning gallbladder visualization on hepatobiliary scintigraphy in infants with persistent jaundice

The purpose of this study was to determine whether gallbladder visualization can help exclude biliary atresia in hepatobiliary scintigraphic studies of infants with persistent jaundice.

METHODS

One hundred fifty-two infants with persistent jaundice (49 patients with a final diagnosis of biliary atresia and 103 with biliary patency) were studied using both hepatobiliary scintigraphy and abdominal sonography. Food was withheld for 4 h before the examination, and the infants were fed nothing but glucose until 6 h after the initial injection of (99m)Tc-disofenin or until the gallbladder was seen. If the gallbladder was seen, the infants were fed milk, and imaging was continued to observe gallbladder contractility.

RESULTS

In none of the 49 patients with biliary atresia could the gallbladder be seen with hepatobiliary scintigraphy, but abdominal sonography revealed 9 normal-sized gallbladders. Of the 103 patients with biliary patency, hepatobiliary scintigraphy detected the gallbladder more frequently (74%, 76/103) than did abdominal sonography (63%, 65/103). All visualized gallbladders contracted after the infants were fed milk. If we include visualization of both the gallbladder and bowel radioactivity as criteria, the specificity of biliary atresia on hepatobiliary scintigraphy increases to 86% (89/103).

CONCLUSION

Gallbladders were usually visible on hepatobiliary scintigraphy of fasting patients with biliary patency. A functioning gallbladder, with or without visualization of bowel radioactivity, indicated biliary patency.

Cloning and expression of an acidic pectin methylesterase from jelly fig (Ficus awkeotsang)

Pectin methylesterase (PME) is the key enzyme responsible for the gelation of jelly curd in the water extract of jelly fig (Ficus awkeotasang) achenes. The jelly fig PME extracted from achenes was isoelectrofocused at pH 2.5 and subjected to N-terminal amino acid sequencing. A cDNA fragment encoding the mature protein of this acidic PME was obtained by PCR cloning using a poly(T) primer and a degenerate primer designed according to the N-terminal sequence of the purified PME. The complete cDNA sequence of its precursor protein was further obtained by PCR using the same strategy. The PME clone was overexpressed in Escherichia coli, and its expressed protein was immunologically recognized as strongly as the original antigen using antibodies against purified PME. Fractionation analysis revealed that the overexpressed PME was predominantly present in the pellet and thus presumably formed insoluble inclusion bodies in E. coli cells.

Comparison of preferences for health outcomes in schizophrenia among stakeholder groups

BACKGROUND

To determine the effectiveness of psychiatric interventions for use in cost-effectiveness analysis, we assessed the feasibility of using a multimedia computer survey to study preferences (utilities) for health outcomes among persons with schizophrenia, family members of persons with schizophrenia, health professionals, and the public.

METHODS

We developed videos depicting two patterns of mental health impairment in schizophrenia, both with and without pseudo-parkinsonism side-effects. These descriptions were integrated into a computer program that measured preferences using two psychometric methods: (1) standard gamble and (2) a visual analog scale. This program was used to compare preferences among potential stakeholder groups.

RESULTS

20 persons with schizophrenia, 11 family members, 20 healthy volunteers and 14 health professionals participated in the computerized interview. All but one subject completed the survey. The correlation among ratings of various states was high (r=0.7-0.95) and ratings were internally consistent in 89% of participants. There were significant differences in values between groups for health states (p=0.024) and in values for the effects of pseudo-parkinsonism on quality of life (p<0.001). Persons with schizophrenia valued the disease states more highly and placed more significance than did other groups on the effects of pseudo-parkinsonism on quality of life.

CONCLUSIONS

Computer-based multimedia techniques can offer a feasible and valid approach to measure preferences for outcomes in schizophrenia. The study found significant differences in preferences among stakeholder groups for schizophrenia outcomes. Further work is needed to clarify how these differences affect clinical decision-making and policies for health resource allocation.

The impact of race on freedom from prostate-specific antigen failure in prostate cancer patients treated with definitive radiation therapy

Many studies have reported that African-American men have the highest incidence and mortality rates for prostate cancer in the United States. A retrospective analysis of 607 patients treated with definitive radiation therapy was performed at the University of California San Francisco and its affiliated hospitals between 1987 and 1995. The patient population analyzed included African-American, Caucasian, and Asian men with AJCC T1-T3 disease. Race, Gleason score, pretreatment prostate-specific antigen levels, stage, and treatment delivery were all evaluated. The percent free from PSA failure at 48 months for African-American, Caucasian, and Asian men were 53%, 59%, and 53%, respectively. There was no difference among the three races or for any of the pairwise comparisons. Gleason score and stage of disease were each independent predictors of outcome, but race was not associated with remaining free from PSA failure. These results are similar to those recently reported in the literature from centers of excellence across the United States.

Outcome after surgical treatment of progressive posttraumatic cystic myelopathy

OBJECT

Progressive posttraumatic cystic myelopathy (PPCM) can occur after an injury to the spinal cord. Traditional treatment of PPCM consists of inserting a shunt into the cyst. However, some authors have advocated a more pathophysiological approach to this problem. The authors of the present study describe their surgical treatment protocol and outcome in a series of patients with syringomyelia.

METHODS

Medical records of 34 patients undergoing surgical treatment for PPCM were reviewed. Laminectomies and intraoperative ultrasonography were performed. In patients without focal tethering of the spinal cord and in whom only a confluent cyst had been revealed on ultrasonography, a syringosubarachnoid shunt was inserted; in those with both tethering and a confluent cord cyst, an untethering procedure was performed first. When a significant reduction (>50%) in the size of the cyst was shown after the untethering procedure, no shunt was inserted. When no changes in cyst size were demonstrated on ultrasonography, a short syringosubarachnoid shunt was used. The mean follow-up period was 28.7 months (range 12-102 months). The interval between the mechanism of injury and the operation ranged from 5 months to 37 years (mean 11 years). Pain was the most frequent symptom, which was followed by motor deterioration and spasticity. Postoperative improvement was noted in 55% of patients who experienced motor function deterioration and in 53% of those who demonstrated worsening spasticity. In 14 of 18 patients with an associated tethered spinal cord, tethering alone caused significant collapse of the cyst. Postoperative magnetic resonance imaging demonstrated cyst collapse in 92% of patients who had undergone untethering alone and in 93% of those who underwent syringosubarachnoid shunt placement. Treatment failure was observed in 7% of the former group and in 13% of the latter.

CONCLUSIONS

Posttraumatic cystic myelopathy can occur with or without the presence of tethered cord syndrome. Intraoperative ultrasonography can readily demonstrate this distinction to aid in surgical decision making. Untethering alone in patients with tethered cord syndrome and cyst formation can reduce the cyst size and alleviate symptoms and signs of posttraumatic cystic myelopathy in the majority of these cases. Untethering procedures in which duraplasty is performed to expand the subarachnoid space may be a more physiologically effective way of treating tethered cord with associated syringomyelia.

Effects of subunit occupancy on partitioning of an intermediate in thymidylate synthase mutants

Experimental evidence for a 5-exocyclic methylene-dUMP intermediate in the thymidylate synthase reaction was recently obtained by demonstrating that tryptophan 82 mutants of the Lactobacillus casei enzyme produced 5-(2-hydroxyethyl)thiomethyl-dUMP (HETM-dUMP) (Barret, J. E., Maltby, D. A., Santi, D. V., and Schultz, P. G. (1998) J. Am. Chem. Soc. 120, 449-450). The unusual product was proposed to emanate from trapping of the intermediate with beta-mercaptoethanol in competition with hydride transfer from H(4)folate to form dTMP. Using mutants of the C-terminal residue of thymidylate synthase, we found that the ratio of HETM-dUMP to dTMP varies as a function of CH(2)H(4)folate concentration. This observation seemed inconsistent with the conclusion that both products arose from a common intermediate in which CH(2)H(4)folate was already bound to the enzyme. The enigma was resolved by a kinetic model that allowed for differential partitioning of the intermediate formed on each of the two subunits of the homodimeric enzyme in forming the two different products. With three C-terminal mutants of L. casei TS, HETM-dUMP formation was consistent with a model in which product formation occurs upon occupancy of the first completely bound subunit, the rate of which is unaffected by occupancy of the second subunit. With one analogous E. coli TS mutant, HETM-dUMP formation occurred upon occupancy of the first subunit, but was inhibited when both subunits were occupied. With all mutants, dTMP formation occurs from occupied forms of both subunits at different rates; here, binding of cofactor to the first subunit decreased affinity for the second, but the reaction occurred faster in the enzyme form with both subunits bound to dUMP and CH(2)H(4)folate. The model resolves the apparent enigma of the cofactor-dependent product distribution and supports the conclusion that the exocyclic methylene intermediate is common to both HETM-dUMP and dTMP formation.

Early MRI findings in high grade glioma

Magnetic resonance imaging (MRI) is more sensitive than computerized tomography in the detection of many intracerebral lesions; however, the significance of some MRI findings may be unclear. Over four years, nine patients, aged 40-79 years, have been encountered whose initial MRI scans were negative or had minimal abnormalities and soon thereafter had high grade glioma. Initial MRI was performed in eight patients for new-onset seizures and one patient for a focal deficit. MRI was negative in four of the patients and mildly abnormal in five of the patients (small areas of increased T2 and/or minimal enhancement). The initial diagnoses usually included inconclusive differentials of stroke and infection with neoplasm less frequently considered. Radiographic progression leading to the diagnosis of high grade glioma became evident on repeat MRI in 1-8 months with six patients showing progression within three months. All patients underwent surgery and had histologic diagnosis of glioma. Although MRI is quite sensitive, four of the initial scans were negative with reasonable quality studies. Conversely, in five of the initial scans, the tumors were detected when so small that the radiographic findings were not typically diagnostic. Glioma must be considered as a possible cause of initial seizures or new neurologic deficits in adults with normal or minimally abnormal MRI. In this group, seizures were the overwhelming hallmark of presentation. In such a clinical situation, close follow-up with short interval repeat MRI should be performed.

Adaptational process of parents of pediatric oncology patients

This study, based on grounded theory, explores the adaptational process of parents of pediatric oncology patients. Thirty-two Taiwanese parents (26 mothers and 6 fathers) were interviewed. Data were collected through individual in-depth and focus group interviews, observations, medical chart review, nurses' note, and researchers' reflexive journals. The findings suggest that parents adapt to their children's cancer by a dynamic process; i.e., they modify their coping tasks and related strategies as clinical events (e.g., diagnosis, side effects, relapses, or death) occur. This adaptational process consisted of five components: confronting treatment, maintaining family integrity, establishing support, maintaining emotional well-being, and searching for spiritual meaning. Related factors such as coping tasks are described.

What a physician needs to know about cost-effectiveness

The cost of medical care in the United States continues to spiral upward, partly as a result of new technological breakthroughs that promise improved length of life and quality of life for patients. But how good are these treatments in everyday practice? How do we make policies for adopting innovations that improve outcome but also increase costs? Cost-effectiveness studies are designed to answer these questions. They reveal important aspects of a particular medical decision and inform treatment choices by systematically analyzing the relationships between the costs and outcomes of alternative health care interventions. This article provides an introduction to the field of cost-effectiveness analysis and describes an approach to interpreting the rapidly proliferating cost-effectiveness literature.

Survey on neurosurgery subspecialty fellowship training. Congress of Neurological Surgeons Education Committee

BACKGROUND

The ongoing controversy on the certification of neurosurgery subspecialties has not been settled. There has been no detailed report on why a resident chooses to undergo further training in the form of a postgraduate fellowship. A survey was devised to investigate the reasons, as well as factors, that prompt the resident to pursue fellowship training.

METHODS

The names of the surveyed residents were obtained from the Congress of Neurological Surgeons database, and the names of the neurosurgery fellows were obtained from individual program coordinators by phone. A survey, a cover letter, and a return envelope were mailed to each prospective respondent. The data were entered on the Paradox for Windows program, and multiple queries were run to obtain tabulated results.

RESULTS

The overwhelming majority (84.6%) of the resident respondents considered fellowship a possibility. Academic medicine was also the choice of career for most (60.3%). The most popular reported fellowships were spine (25.6%), pediatric (16.5%), and vascular (16.1%). The three top reasons for pursuing fellowship training were "personal interest for knowledge," "job market demand," and "academic prestige." "Inadequate training during residency" was a distant fourth. For respondents citing "inadequate training during residency" as one of the top three reasons, there were proportionally higher respondents in the fields of peripheral nerve, endovascular, and skull base neurosurgeries.

CONCLUSION

A significant number of residents consider fellowship a way to further their personal interest and knowledge, as well as increase their marketability. Relatively few from the surveyed group considered their residency training experience deficient in the subspecialty areas, with the exception of peripheral nerve, endovascular, and possibly skull base neurosurgery.

Neuroprotective effects of basic fibroblast growth factor following spinal cord contusion injury in the rat

Cytokines and neurotrophic factors have been implicated in the pathophysiology of injury to the central nervous system. While some cytokines are considered pro-inflammatory, other factors promote neuronal growth and survival. The present study investigated the neuroprotective effects of interleukins 1 (IL-1), 4 (IL-4), and 6 (IL-6), nerve growth factor (NGF), ciliary neurotrophic factor (CNTF), and basic fibroblast growth factor (bFGF) in a contusion model of spinal cord injury. Female Sprague-Dawley rats (n = 55) sustained a 10-g weight-drop injury to the lower thoracic spinal cord (T10) from a height of 12.5 mm using the NYU impactor. A micro-infusion system (Alzet minipump) was used to continuously deliver drugs or vehicle directly into the epicenter of the contused spinal cord starting 1 or three h postinjury. At the end of 7 days, animals were perfused and the cords removed for histopathological analysis. Longitudinal serial sections were cut on a freezing microtome and stained with cresyl violet. Areas of central necrosis, partial preservation, and total zone of tissue injury were identified and traced by an independent reviewer using a computer based imaging system. The mean total zone of injury in five animals receiving vehicle infusion was 18.04+/-4.20 mm3. The mean zone of partial preservation in these animals was 16.46+/-3.32 mm. Basic fibroblast growth factor reduced the total zone of injury by 33% [p<0.01, least significant difference (LSD) of Fisher] in five animals and the zone of partial preservation by 32% (p<0.01, LSD of Fisher) when compared to controls. There were trends toward reduction in total zone of injury and zone of partial preservation in rats treated with IL-4, CNTF, and NGF versus vehicle; however, none of these reached statistical significance. No significant differences were observed between animals receiving vehicle versus bFGF treatment commencing 3 h after injury. These data demonstrate that the continuous intramedullary infusion of bFGF initiated one hour after moderate contusion injury of the spinal cord significantly reduces the total zone of injury and the zone of partial preservation. These results support the further investigation and possible future clinical application of bFGF in the treatment of acute spinal cord contusion injury.

Unique clinical presentation of pediatric shunt malfunction

INTRODUCTION

A cerebrospinal fluid (CSF) shunt is the primary treatment for most etiologies of hydrocephalus in the pediatric population. Malfunction of the shunt may present with unique symptoms and signs. This retrospective review investigates the presenting signs and symptoms of pediatric patients with shunt malfunction. Clinical

MATERIAL AND METHOD

One-hundred-and-thirty CSF diversion procedures were performed at two affiliated pediatric hospitals over a 2-year period. Seventy consecutive cases of CSF shunt revision were reviewed. These 70 operations were performed on 65 patients. Their medical records and radiographic studies were reviewed, and supplemented with a telephone interview to obtain a minimum of 3 months follow-up.

RESULTS

The 65 patients' age ranged from 3 months to 16 years. The original etiology of the hydrocephalus was Chiari II malformation in 17, idiopathic in 15 and intraventricular hemorrhage in 10, neoplasm in 8 patients and meningitis in 5 patients. The most frequent presenting symptoms were headache (39 admissions), nausea/vomiting (28) and drowsiness (21). Seven Chiari patients (41%) presented with neck pain, 2 (12%) presented with lower cranial nerve palsy, and 2 (12%) presented with symptomatic syrinx, complaints not reported by non-Chiari patients (p < 0.01, chi2 analysis). Four myelodysplastic patients presented with a new-onset or recurrent seizure episode, which was significantly more frequent than in nonmyelodysplastic patients (p < 0.05, chi2 analysis). On examination, increased head circumference was noted in 17 patients. Parinaud's syndrome was noted more prominently in patients with a history of intracranial neoplasm (4 of 8 cases) than in patients with nonneoplastic diseases (2 of 62 cases; p < 0.05, chi2 analysis). Other interesting presenting signs were pseudocyst (2), syringomyelia (2), hemiparesis (2) and Parkinson-like rigidity (2).

CONCLUSION

Pediatric shunt malfunction generally presents with headache, nausea/vomiting, altered mental status, increased head circumference and bulging fontanelle. Other less frequent but unique presenting signs and symptoms, such as neck pain, syringomyelia and lower cranial nerve palsy in the myelodysplastic population, and Parinaud's syndrome in patients with a history of intracranial neoplasm are frequently associated with shunt malfunction and should prompt a radiographic workup.

Rapid platelet-function assay: an automated and quantitative cartridge-based method

BACKGROUND

The platelet glycoprotein (GP) IIb/IIIa receptor is important in mediating platelet thrombus formation, and the GP IIb/IIIa antagonist abciximab (c7E3 Fab; ReoPro) is effective in preventing thrombotic ischemic cardiovascular complications of unstable angina and percutaneous coronary interventions. Small-molecule antagonists of GP IIb/IIIa based on the Arg-Gly-Asp (RGD) sequence show similar benefit, and some of these agents are orally active. However, there may be significant interindividual variation in response to such antagonists, especially with chronic oral therapy. It will be essential to balance the beneficial antithrombotic effect of these drugs with their potential for causing bleeding. In response to this need, we have developed a rapid platelet-function assay (RPFA), a point-of-care system that provides a quantitative measure of the competence of the GP IIb/IIIa receptor as reflected in the ability of platelets to agglutinate fibrinogen-coated beads.

METHODS AND RESULTS

Polystyrene beads were coated with fibrinogen and placed in a cartridge along with a lyophilized peptide that activates the thrombin receptor. Anticoagulated whole blood was added to the cartridge, and then a microprocessor-controlled operation mixed the reagents and detected agglutination between platelets and coated beads. Quantitative digital results were displayed within 3 minutes. Because there is no dilution of the blood, the assay can be used to measure platelet activity in samples that have been treated with GP IIb/IIIa antagonists with high dissociation rates. RPFA results of whole-blood samples treated with different GP IIb/IIIa antagonists correlated well with both conventional turbidimetric platelet aggregation (r2=0.95) and the percentage of free GP IIb/IIIa molecules in the sample (r2=0.96). The mean difference in measurements between RPFA and aggregometry was -4% (+/-4% SD), and the mean difference in measurements between RPFA and free GP IIb/IIIa receptors was -2% (+/-6% SD).

CONCLUSIONS

The RPFA provides rapid information on platelet function that mirrors turbidimetric platelet aggregation and reflects GP IIb/IIIa receptor blockade.

His68 and His141 are critical contributors to the intersubunit catalytic site of adenylosuccinate lyase of Bacillus subtilis

Mutant adenylosuccinate lyases of Bacillus subtilis were prepared by site-directed mutagenesis with replacements for His141, previously identified by affinity labeling as being in the active site [Lee, T. T., Worby, C., Dixon, J. E., and Colman, R. F. (1997) J. Biol. Chem. 272, 458-465]. Four substitutions (A, L, E, Q) yield mutant enzyme with no detectable catalytic activity, while the H141R mutant is about 10(-)5 as active as the wild-type enzyme. Kinetic studies show, for the H141R enzyme, a Km that is only 3 times that of the wild-type enzyme. Minimal activity was also observed for mutant enzymes with replacements for His68 [Lee, T. T., Worby, C., Bao, Z. -Q., Dixon, J. E., and Colman, R. F. (1998) Biochemistry 37, 8481-8489]. Measurement of the reversible binding of radioactive adenylosuccinate by inactive mutant enzymes with substitutions at either position 68 or 141 shows that their affinities for substrate are decreased by only 10-40-fold. These results suggest that His141, like His68, plays an important role in catalysis, but not in substrate binding. Evidence is consistent with the hypothesis that His141 and His68 function, respectively, as the catalytic base and acid. Circular dichroism spectroscopy and gel filtration chromatography conducted on wild-type and all His141 and His68 mutants reveal that none of the mutant enzymes exhibits major structural changes and that all the enzymes are tetramers. Mixing inactive His141 with inactive His68 mutant enzymes leads to striking increases in catalytic activity. This complementation of mutant enzymes indicates that His141 and His68 come from different subunits to form the active site. A tetrameric structure of adenylosuccinate lyase was constructed by homology modeling based on the known structures in the fumarase superfamily, including argininosuccinate lyase, delta-crystallin, fumarase, and aspartase. The model suggests that each active site is constituted by residues from three subunits, and that His141 and His68 come from two different subunits.

Diffuse cerebral vasospasm with ischemia after resection of a cerebellopontine angle primitive neuroectodermal tumor in a child

This case report describes a 15-month-old female who developed diffuse cerebral vasospasm after resection of a cerebellopontine angle primitive neuroectodermal tumor. The patient developed an acute dense left hemiparesis 16 days postoperatively with partial right ptosis. Initial magnetic resonance imaging and diffusion study were unremarkable, though a magnetic resonance angiography 1 day later demonstrated severe intracranial vasospasm of both carotid and vertebral arteries. The vasospasm was confirmed with cerebral angiography. The patient progressed to bihemispheric infarcts with laminar necrosis despite combination therapy with anticoagulation, pharmacological hypertension, hypervolemia, and nimodipine. The clinical course, radiographic, and pathological findings are presented.

Spinal metastases of malignant intracranial meningioma

BACKGROUND

Spinal metastasis of intracranial meningiomas has rarely been reported. Three out of ten previously reported cases of malignant meningioma metastasizing to the spine had undergone surgical debulking with no neurological improvement. The authors retrospectively reviewed the treatment course of three patients with malignant meningioma metastasizing to the spine who underwent early magnetic resonance imaging (MRI) and radiotherapy without surgical debulking.

CASE DESCRIPTION

Three patients with intracranial malignant meningiomas underwent multiple resections of intracranial lesions, and developed spinal intradural metastases an average of 64 months (range, 27-102 months) from their initial presentation. All three patients had at least two operations for recurrent intracranial tumors. All had localized back pain with motor weakness, and MRI scans demonstrated spinal involvement. No surgical exploration was performed for the spinal lesions; rather, all patients received steroids and radiotherapy for the spinal lesions. All three patients improved neurologically after the steroid and radiation treatments, and went on to survive from 3 to 18 months.

CONCLUSION

Early MRI should be performed in patients with spinal symptoms and signs after the treatment of intracranial meningiomas. Radiotherapy is an effective palliative treatment for spinal metastases.

Empirically defined health states for depression from the SF-12

OBJECTIVE

To define objectively and describe a set of clinically relevant health states that encompass the typical effects of depression on quality of life in an actual patient population. Our model was designed to facilitate the elicitation of patients' and the public's values (utilities) for outcomes of depression.

DATA SOURCES

From the depression panel of the Medical Outcomes Study. Data include scores on the 12-Item Short Form Health Survey (SF-12) as well as independently obtained diagnoses of depression for 716 patients. Follow-up information, one year after baseline, was available for 166 of these patients.

METHODOLOGY

We use k-means cluster analysis to group the patients according to appropriate dimensions of health derived from the SF-12 scores. Chi-squared and exact permutation tests are used to validate the health states thus obtained, by checking for baseline and longitudinal correlation of cluster membership and clinical diagnosis.

PRINCIPAL FINDINGS

We find, on the basis of a combination of statistical and clinical criteria, that six states are optimal for summarizing the range of health experienced by depressed patients. Each state is described in terms of a subject who is typical in a sense that is articulated with our cluster-analytic approach. In all of our models, the relationship between health state membership and clinical diagnosis is highly statistically significant. The models are also sensitive to changes in patients' clinical status over time.

CONCLUSIONS

Cluster analysis is demonstrably a powerful methodology for forming clinically valid health states from health status data. The states produced are suitable for the experimental elicitation of preference and analyses of costs and utilities.

Treatment of stable burst fracture of the atlas (Jefferson fracture) with rigid cervical collar

STUDY DESIGN

A retrospective review of a clinical series.

OBJECTIVE

To evaluate the use of a rigid cervical collar alone as the treatment for stable Jefferson fracture, and to devise an algorithm for treatment of Jefferson fracture with or without an associated cervical injury.

SUMMARY OF BACKGROUND DATA

The traditional treatment for Jefferson fracture, if there is no indication for surgery, is immobilization by halo vest. Because halo vest placement is associated with intracranial infection and a significant degree of patient discomfort, slightly less rigid forms of external immobilization may be useful for the treatment of stable Jefferson fractures. No standard protocol calling for the use of one form of stabilization device has been reported.

MATERIALS

The medical records and radiographs of 16 consecutive patients with Jefferson fracture during a 2-year period were reviewed. Each patient underwent a complete cervical radiograph series and a computed tomographic scan. The mean C1 lateral mass displacement was 1.8 mm. Cervical spine radiographs, including lateral flexion-extension views were obtained 10 to 12 weeks after injury before the removal of an external immobilization device.

RESULTS

Of these 16 patients, 1 sustained a complete injury, and 7 sustained an incomplete injury. Eight patients were neurologically intact. Twelve patients sustained a stable Jefferson fracture and were treated with a rigid cervical collar (Miami-J collar [Jerome Medical, Moorestown, NJ]) alone from 10 to 12 weeks. The patient sustaining the complete neurologic injury died of multisystem trauma. All 15 live patients showed no instability on their follow-up plain radiographs before the removal of an external stabilization device. Six patients underwent further plain radiographs approximately 1 year after the fracture and similarly demonstrated no instability.

CONCLUSIONS

Isolated stable burst fracture of the atlas can be treated effectively with a rigid cervical collar alone for 10 to 12 weeks with good neurologic recovery and segmental stability. Unstable Jefferson fractures with concurrent unstable fracture of other cervical vertebrae, especially C2, requires surgical stabilization.

Surgical treatment of spinal ependymoma and post-operative radiotherapy

INTRODUCTION

With the advances in microsurgical and monitoring techniques, spinal ependymomas are gross totally resected more frequently. The use of adjuvant radiotherapy has become questionable with gross total resection and its role for residual neoplasm need to be redefined. A retrospective analysis of a series of patients was carried out to investigate our clinical outcome and selected use of post-operative radiotherapy.

CLINICAL MATERIALS AND METHODS

Between July 1990 and May 1995, nineteen patients [M : F = 12 : 7; age range: 21 to 71 years] with a spinal ependymoma were treated at University of Miami by the senior author. (BAG) Pre-operative MRI diagnosed the intraspinal tumor, and pathology reports demonstrated that each patient had a histologically confirmed ependymoma. At the time of diagnosis, the most common symptoms presented were pain (in 16 patients = 84.2%). The pattern of progression of clinical symptoms was directly related to the location of the tumor. Each patient had an MRI immediately after surgery, approximately 6 months post-operatively, and then annually.

RESULTS

All 19 patients underwent intradural microsurgical exploration with an attempted gross total resection (achieved in 16 patients = 79%) of the ependymoma through a posterior approach. Direct neural tissue stimulation halted further resection in 2 patients with questionable tumor margins. Radiation therapy was employed as a surgical adjunct in 3 patients (15.8%) because of possible residual tumor. All patients were followed up postoperatively for an average of 50.6 months (range 6 months to 6 years). All patients are surviving to date. Surgical resection of these tumors led to significant alleviation of pre-operative symptom. There has been no radiographic evidence of tumor recurrence or growth in any patient to date.

CONCLUSION

Surgical resection of spinal ependymoma leads to significant improvement of pre-operative symptoms. Surgical removal alone, with an attempt to grossly resect the tumor, should be the treatment of choice, with careful clinical and radiographic follow-up. Radiation therapy should only be considered as a surgical adjunct where gross total resection is not achieved.

Diagnostic and surgical management of spinal dural arteriovenous fistulas

OBJECTIVE

A retrospective review was conducted to compare magnetic resonance (MR) and conventional spinal angiographic images and to investigate the outcome of our treatment protocol for patients with spinal dural arteriovenous fistulas (DAVFs).

MATERIALS AND METHODS

Nine patients with a diagnosis of DAVF based on clinical myelopathy and preoperative MR imaging (MRI) and MR angiography (MRA) findings were treated at our institution by the senior author (BAG). All nine patients initially presented with progressive myelopathy. Preoperative MRI revealed T2-weighted signal abnormalities in all patients, and MRA was diagnostic in all patients. Each patient underwent a laminectomy and ligation of the arterialized draining vein. Selective spinal angiograms were used to confirm the level of fistula immediately before the surgical procedure was performed and to document complete obliteration after clip ligation of the medullary draining vein. Follow-up MRI and MRA were performed approximately 2 months postoperatively.

RESULTS

MRI T2-weighted signal hyperintensity improved after surgery in all nine patients. Postoperatively, progression of motor weakness and gait difficulty was halted and some improvement was observed in all patients. No patient was neurologically normal, however. To date, there has been no clinical or MRA evidence of recurrence in any patient.

CONCLUSION

Preoperative MRA and intraoperative spinal x-ray angiography present as an effective combination for diagnosing and intraoperatively confirming DAVF. Both T1-weighted enhancement and T2-weighted signal hyperintensity on MR images improved after the obliteration of the DAVFs and correlated with clinical improvement in all nine patients. MRA provides adequate visualization and localization of spinal DAVFs and may serve as a useful noninvasive tool for diagnosing and following patients with spinal DAVFs in the future.

Implication of His68 in the substrate site of Bacillus subtilis adenylosuccinate lyase by mutagenesis and affinity labeling with 2-[(4-bromo-2,3-dioxobutyl)thio]adenosine 5'-monophosphate

Adenylosuccinate lyase of Bacillus subtilis is inactivated by 2-[(4-bromo-2,3-dioxobutyl)thio]adenosine 5'-monophosphate (2-BDB-TAMP) at pH 7.0. As the reagent concentration is increased, a maximum rate constant is approached, indicative of reversible enzyme-reagent complex formation (KR = 68 +/- 9 microM) prior to irreversible modification (kmax = 0.081 +/- 0.004 min-1). Complete inactivation occurs concomitant with about 1 mol of 2-BDB-[14C]TAMP incorporated/mol of enzyme subunit. Adenylosuccinate, or a combination of AMP and fumarate, decreases the inactivation rate and reduces incorporation of [14C] reagent, whereas either AMP or fumarate alone is much less effective. These observations suggest that 2-BDB-TAMP attacks the adenylosuccinate binding site. Proteolytic digestion of inactivated enzyme, followed by purification of the digest by HPLC, yields the radioactive peptide Ile62-Ala72, in which Arg67 and His68 are the most likely targets. Thus 2-BDB-TAMP reacts with adenylosuccinate lyase at a site distinct from the His141 attacked by 6-BDB-TAMP (Lee, Worby, Dixon, and Colman (1997) J. Biol. Chem. 272, 458-465). Site-directed mutagenesis was used to construct mutant enzymes with replacements for both Arg67 and His68, and either Arg67 or His68. The R67M mutant enzyme has almost the same specific activity as the wild-type enzyme under standard assay conditions, whereas the single mutant H68Q and double mutant R67M-H68Q enzymes exhibit specific activities that are decreased more than 100-fold. These results indicate that while Arg67 and His68 may both be in the region of the substrate site, only His68 is important for the catalytic activity of B. subtilis adenylosuccinate lyase. A role is proposed for His68 as a general acid-base catalyst.

Traumatic spinal cord injury induces nuclear factor-kappaB activation

Inflammatory responses are a major component of secondary injury and play a central role in mediating the pathogenesis of acute and chronic spinal cord injury (SCI). The nuclear factor-kappaB (NF-kappaB) family of transcription factors is required for the transcriptional activation of a variety of genes regulating inflammatory, proliferative, and cell death responses of cells. In this study we examined the temporal and cellular expression of activated NF-kappaB after traumatic SCI. We used a contusion model (N.Y.U. Impactor) to initiate the early biochemical and molecular changes that occur after traumatic injury to reproduce the pathological events associated with acute inflammation after SCI. The activation and cellular distribution of activated NF-kappaB was evaluated by using a monoclonal antibody that selectively recognizes activated p65 in a NF-kappaB dimer. Immunohistochemical and Western blot analyses demonstrated that NF-kappaB activation occurred as early as 0.5 hr postinjury and persisted for at least 72 hr. Using electrophoretic mobility shift assays (EMSA), we demonstrate that NF-kappaB is activated after SCI. In our immunohistochemical, Western, and EMSA experiments there are detectable levels of activated NF-kappaB in our control animals. Using double-staining protocols, we detected activated NF-kappaB in macrophages/microglia, endothelial cells, and neurons within the injured spinal cord. Colocalization of activated NF-kappaB with the NF-kappaB-dependent gene product, inducible nitric oxide synthase (iNOS), suggests functional implications for this transcription factor in the pathogenesis of acute spinal cord injury. Although there is considerable evidence for the involvement of an inflammatory reaction after traumatic SCI, this is the first evidence for the activation of NF-kappaB after trauma. Strategies directed at blocking the initiation of this cascade may prove beneficial as a therapeutic approach for the treatment of acute SCI.

Diffuse axonal injury (DAI) is not associated with elevated intracranial pressure (ICP)

OBJECTIVE

Traditionally, intracranial pressure (ICP) monitoring has been utilized in all patients with severe head injury (Glasgow coma score of 3-8). Ventriculostomy placement, however, does carry a 4 to 10 percent complication rate consisting mostly of hematoma and infection. The authors propose that a subgroup of patients presenting with severe head trauma and diffuse axonal injury without associated mass lesion, do not need ICP monitoring. Additionally, the monitoring data from ICP, MAP, and CPP for a comparison severe head injury group, and subgroups of DAI would be presented.

MATERIALS AND METHODS

Thirty-six patients sustaining blunt head trauma and fitting our strict clinical and radiographic diagnosis of DAI were enrolled in our study. Inclusion criteria were severe head injury patients who did not regain consciousness after the initial impact, and whose CT scan demonstrated characteristic punctate hemorrhages of < 10 mm diameter at the greywhite junction, basal ganglia, corpus callosum, upper brainstem, or a combination of the above. Patients with significant mass lesions and documented anoxia were excluded. Their intracranial pressure (ICP) and cerebral perfusion pressure (CPP) were compared to a control group of 36 consecutive patients with severe non-penetrating non-operative head injury, using the Analysis for Variance method.

RESULTS

Eighteen (50.0%), six (16.7%), and twelve (33.3%) patients had types I, II, and III DAI, respectively. The admission Glasgow Coma Score (GCS) was higher for types I and II than for type III DAI. ICP was monitored from 23 to 165 hours, with a mean ICP for 36 patients of 11.70 mmHg (SEM = 0.75) and a range from 4.3 to 17.3 mmHg. Of all ICP recordings, of which 89.7%, (2421/2698) were < or = 20 mmHg. Average mean arterial pressure (MAP) was 96.08 mmHg (SEM = 1.69), and 94.6% (2038/2154) of all MAP readings were greater than 80 mmHg. Average cerebral perfusion pressure (CPP) was 85.16 mmHg (SEM = 1.68), and 90.1% (1941/2154) of all CPP readings were greater than 70 mmHg. This is compared to the control group mean ICP, MAP, and CPP of 16.84 mmHg (p = 0.000021), 92.80 mmHg (p = 0.18), and 76.49 mmHg (p = 0.0012). No treatment for sustained elevated ICP > 20 mmHg was needed for DAI patients except in two; one with extensive intraventricular and subarachnoid hemorrhage who developed communicating hydrocephalus, and another with ventriculitis requiring intrathecal and intravenous antibiotic treatments. Two complications, one from a catheter tract hematoma, and another with Staph epidermidis ventriculitis, were encountered. All patients, except type III DAI, generally demonstrated marked clinical improvement with time. The outcome, as measured by Glasgow Coma Score (GCS) and Glasgow Outcome Score (GOS) was similarly better with types I and II than type III DAI.

CONCLUSION

The authors conclude that ICP elevation in DAI patients without associated mass lesions is not as prevalent as other severe head injured patients, therefore ICP monitoring may not be as critical. The presence of an ICP monitoring device may contribute to increased morbidity. Of key importance, however, is an accurate clinical history and interpretation of the CT scan.