Ageing of juvenile coral grouper (Plectropomus maculatus) reveals year-round spawning and recruitment: implications for seasonal closures.

Temporal patterns in spawning and juvenile recruitment can have major effects on population size and the demographic structure of coral reef fishes. For harvested species, these patterns are crucial in determining stock size and optimizing management strategies such as seasonal closures. For the commercially important coral grouper (Plectropomus spp.) on the Great Barrier Reef, histological studies indicate peak spawning around the summer new moons. Here we examine the timing of spawning activity for P. maculatus in the southern Great Barrier Reef by deriving age in days for 761 juvenile fish collected between 2007 and 2022, and back-calculating settlement and spawning dates. Age-length relationships were used to estimate spawning and settlement times for a further 1002 juveniles collected over this period. Unexpectedly, our findings indicate year-round spawning activity generates distinct recruitment cohorts that span several weeks to months. Peak spawning varied between years with no clear association with environmental cues, and little to no alignment with existing seasonal fisheries closures around the new moon. Given the variability and uncertainty in peak spawning times, this fishery may benefit from additional and longer seasonal closures, or alternative fisheries management strategies, to maximize the recruitment contribution from periods of greatest reproductive success.

Efficacy of detergent-based cleaning and wiping against SARS-CoV-2 on high-touch surfaces.

Efficacy of cleaning methods against SARS-CoV-2 suspended in either 5% soil load (SARS-soil) or simulated saliva (SARS-SS) was evaluated immediately (hydrated virus, T0) or 2 hours post-contamination (dried virus, T2). Hard water dampened wiping (DW) of surfaces, resulted in 1.77-3.91 log reduction (T0) or 0.93-2.41 log reduction (T2). Incorporating surface pre-wetting by spraying with a detergent solution (D + DW) or hard water (W + DW) just prior to dampened wiping did not unilaterally increase efficacy against infectious SARS-CoV-2, however, the effect was nuanced with respect to surface, viral matrix, and time. Cleaning efficacy on porous surfaces (seat fabric, SF) was low. W + DW on stainless steel (SS) was as effective as D + DW for all conditions except SARS-soil at T2 on SS. DW was the only method that consistently resulted in > 3-log reduction of hydrated (T0) SARS-CoV-2 on SS and ABS plastic. These results suggest that wiping with a hard water dampened wipe can reduce infectious virus on hard non-porous surfaces. Pre-wetting surfaces with surfactants did not significantly increase efficacy for the conditions tested. Surface material, presence or absence of pre-wetting, and time post-contamination affect efficacy of cleaning methods.

Growth and maturation of the redlip parrotfish Scarus rubroviolaceus.

This study presents age-based life-history information for the red lip parrotfish Scarus rubroviolaceus based on a 5 year sampling programme from the commercial fishery of American Samoa. Females reached sexual maturity at 31·9 cm fork length (LF ) and 2·6 years and sex change occurred at 42·3 cm LF , although not all females change sex through their ontogeny. The maximum observed age was 14 years and c. 65% of the fishery harvest was above the median LF at sex change.

Growth and reproduction of the highfin grouper Epinephelus maculatus.

Highfin grouper Epinephelus maculatus sampled in Chuuk, Micronesia, exhibited a moderate growth rate and a relatively short life span compared to other epinephelids of a similar size. Combined gonad and otolith analysis provide preliminary evidence that the species conforms to a protogynous sexual pattern. Mean total length at maturity for females was 308 mm with first age at maturity 2·8 years for females and 4 years for males, which differs from other regional studies. Based on the gonado-somatic index and microscopic analysis of gonads, E. maculatus in Chuuk have a 4 month spawning season (January to April) that corresponds with seasonal lows in sea surface water temperature and overlaps with that of other aggregating epinephelids. The estimated von Bertalanffy growth factor (K) was 0·51 year(-1) , while total mortality was 0·34 year(-1) . Current management for E. maculatus in Chuuk includes a January to May catch, sale and export ban, which overlaps with its reproductive season. The effectiveness of these arrangements will require on-going monitoring to determine whether alternative management strategies are required to ensure population persistence.

Comparative demography of commercially important parrotfish species from Micronesia.

Fishery-independent sampling was used to determine growth patterns, life span, mortality rates and timing of maturation and sex change in 12 common parrotfishes (Labridae: tribe Scarinae) from five genera (Calotomus, Cetoscarus, Chlorurus, Hipposcarus and Scarus) in Micronesia. Interspecific variation in life-history traits was explored using multivariate analysis. All species displayed strong sex-specific patterns of length-at-age among which males reached larger asymptotic lengths. There was a high level of correlation among life-history traits across species. Relationships between length-based and age-based variables were weakest, with a tenuous link between maximum body size and life span. Cluster analysis based on similarities among life-history traits demonstrated that species were significantly grouped at two major levels. The first grouping was driven by length-based variables (lengths at maturity and sex change and maximum length) and separated the small- and large-bodied species. Within these, species were grouped by age-based variables (age at maturity, mortality and life span). Groupings based on demographic and life-history features were independent of phylogenetic relationships at the given taxonomic level. The results reiterate that body size is an important characteristic differentiating species, but interspecific variation in age-based traits complicates its use as a life-history proxy. Detailed life-history metrics should facilitate future quantitative assessments of vulnerability to overexploitation in multispecies fisheries.

Age-based demographic and reproductive assessment of orangespine Naso lituratus and bluespine Naso unicornis unicornfishes.

Bluespine unicornfish Naso unicornis and orangespine unicornfish Naso lituratus were sampled in Pohnpei and Guam, Micronesia, over 13 months to identify reproductive and age-based demographic features necessary for informed management. Age and reproductive information were derived from analysis of sagittal otoliths and gonads. Both species had moderate life spans [maximum ages of 23 (N. unicornis) and 14 years (N. lituratus)] compared with published estimates of conspecifics from other locations (>30 years) and of other Naso species. Length at maturation for N. unicornis was similar between Pohnpei and Guam while females consistently matured at a larger size [c. 30 cm fork length (LF )] than males (c. 27 cm LF ). This sex-specific pattern was reversed in N. lituratus for which estimates of maturation length (females: 15 cm LF ; males: 18 cm LF ) were only obtained from Guam. Developmental patterns in female gonads of both species suggested that initiation of maturation occurs very early. Growth patterns of N. lituratus displayed rapid asymptotic growth compared with N. unicornis and other congeners as well as slight sex-specific patterns of length-at-age. Results highlight the considerable spatial variation that may occur in the population biology of these species across various scales. Additionally, proper management remains complicated without improved knowledge of fishery trends and reproductive behaviour in unicornfishes, species that are prime fishery targets in Micronesia and elsewhere.

Reproductive biology of squaretail coralgrouper Plectropomus areolatus using age-based techniques.

The squaretail coralgrouper Plectropomus areolatus was identified as a fast-growing, early maturing and relatively short-lived aggregation-spawning epinephelid. Examinations of sectioned otoliths found females and males first maturing at 2 and 3 years, respectively, suggesting protogynous hermaphroditism; however, no transitionals were observed in samples. Age distribution for the two sexes was similar and both were represented in the oldest age class; however, significant sex-specific differences in size-at-age were identified. Both sexes fully recruit into the fishery at age 4 years and reach 90% of asymptotic length by age 3 years. Underwater visual assessments, combined with the gonado-somatic indices, revealed a 5 month reproductive season, with interannual variability observed in the month of highest density within the spawning aggregation. Catch restrictions on adults during spawning times and at reproductive sites, combined with gear-based management and enhanced enforcement, are recommended to maintain spawning stocks. Based on the available evidence, the sexual pattern for this species is unresolved.

Modelling the time to detection of urban tuberculosis in two big cities in Portugal: a spatial survival analysis.

SETTING: Portuguese National Tuberculosis Control Programme. OBJECTIVE: To examine delays in tuberculosis (TB) diagnosis using a spatial component in two high-incidence cities, Lisbon and Oporto, in Portugal, a low-incidence country. DESIGN: A retrospective nationwide study was conducted based on official TB data between 2010 and 2013 to analyse diagnostic delays at the lowest administrative level (freguesias) using spatial survival analyses, taking into account individual level covariates. RESULTS: Median diagnostic delays in Lisbon (n = 2706 cases) and Oporto (n = 1883) were respectively 62 (range 1-359, mean 81.01) and 60 days (range 1-3544, mean 79.5). In both cities, case detection rates initially rose until 50 days, then stabilised, but rose again at about 200 days. Diagnostic delay was significantly shorter among males and human immunodeficiency virus positive individuals in both cities, but was significantly longer among migrants in Lisbon. There is evidence of spatial correlation between freguesias; different spatial patterns were observed in diagnostic delays and in likelihood of case detection. CONCLUSION: These results are concordant with existing literature. The two study areas present considerable spatial variations in diagnostic delay, highlighting the fact that large cities should not be treated as homogeneous entities. The potential of spatial survival methods in spatial epidemiology is highlighted.

Arachidonic acid metabolism in guinea pig eosinophils: synthesis of thromboxane B2 and leukotriene B4 in response to soluble or particulate activators.

The arachidonic acid metabolism of guinea pig eosinophils isolated from either peritoneal cavity or bronchoalveolar lavages was studied by reverse-phase high-performance liquid chromatography. The purified eosinophils (95-100%) from either source released thromboxane B2 (TxB2), luekotriene B4 (LTB4) and 5-hydroxy eicosatetraenoic acid (5-HETE) following calcium ionophore A23187 stimulation. Quantification by radioimmunoassay indicated that maximal mediator output from the stimulated peritoneal cells was reached at 3 min after stimulation. The increase in production of TxB2 and LTB4 was correlated to increasing calcium ionophore A23187 concentration up to 1.0 micrograms/ml. In addition to calcium ionophore, the guinea pig peritoneal cells were also activated by f-met-leu-phe, phorbol 12-myristate, 13-acetate (PMA), and to lesser extent platelet-activating factor (PAF) to produce TxB2. LTB4 synthesis was stimulated by calcium ionophore, by f-met-leu-phe, as well as by unopsonized glucan, a particulate phagocytotic stimulus. The guinea pig eosinophils do not synthesize sulfidopeptide leukotrienes because of the absence of the specific LTA4 glutathione S-transferase. These results suggest that the guinea pig eosinophils differ from the human circulating eosinophils in the synthetic capacity of lipid mediators derived from arachidonic acid metabolism. This difference may be important in the understanding of the role of the eosinophils in inflammatory reactions such as that which occurs in the bronchial tissues of asthmatics.

Biochemical and functional differences between eosinophils from animal species and man.

Eosinophils were isolated from peritoneal lavages of repeated horse serum-injected guinea pigs or rhesus monkeys and from peripheral blood of normal human donors. Eicosanoid metabolism and chemotaxis by these cells were studied by in vitro techniques. Upon calcium ionophore stimulation guinea pig eosinophils released thromboxane B2 (TXB2) and leukotriene B4 (LTB4) while monkey and human cells produced LTC4, LTB4, and 5-HETE. Guinea pig cells do not synthesize sulfidopeptide LTs, because they lack the specific LTA4 glutathione S-transferase. Guinea pig eosinophils exhibit maximal chemotactic responses to LTB4, zymosan activated plasma, and human recombinant C5a, while producing only a negligible response to platelet activating factor (PAF). Monkey and human cells responded maximally to PAF, but exhibit only a weak response to LTB4. These results suggest that the guinea pig eosinophils differ from monkey and human eosinophils in both the synthetic capacity and functional chemotaxis responses to lipid mediators.

Regulation of the epithelial cell-specific integrin, CD103, by human CD8+ cytolytic T lymphocytes.

BACKGROUND: The destruction of the graft epithelium by CD8+ cytolytic T lymphocytes (CTL) is an important aspect of organ allograft rejection. Our recent finding in a mouse model that the epithelial cell-specific integrin, CD103, defines a subset of CD8+ CTL potentially sheds new light onto such interactions. The goal of the present study was to assess the relevance of these data to the human system. METHODS: CD103 expression by human T-cell populations generated in mixed lymphocyte cultures or isolated from transplant nephrectomy specimens was quantitated using multiparameter FACS analyses. RESULTS: CD103 defined a major subset (26-76%) of CD8+ CTL generated in human mixed lymphocyte cultures; cell sorting experiments confirmed that the CD103+ and CD103- subsets both possess allospecific lytic activity. Anti-transforming growth factor (TGF)-beta blocked the appearance of the CD103+ CTL subset, and persistent expression of CD103 by CD8+ CTL was dependent on bioactive TGF-beta. Isolated CD103+ and CD103- CD8 subsets maintained their phenotypic integrity during in vitro expansion, although optimal CD103 expression on the former was TGF-beta dependent. Although CD103+ cells were rare among activated CD8 cells in peripheral lymphoid compartments (< 10%), analyses of transplant nephrectomy specimens revealed that a major subset (21-61%) of CD8 memory/effector cells that infiltrate rejecting renal allografts express high levels of CD103. CONCLUSIONS: We conclude that CD103 defines a discrete and stable subset of human CD8+ CTL and that CD103 expression by such cells is initiated and maintained by bioactive TGF-beta. These data point to the existence of a human effector subset that is uniquely specialized for the destruction of the graft epithelium.

Disappearance and metabolism of leukotriene B4 during carrageenan-induced pleurisy.

Leukotriene B4 (LTB4) has been implicated as a mediator in the inflammatory process by virtue of its potent chemotactic activity. At present, very little is known of the stability of this compound in vivo; therefore, the present study was designed to determine the half-life and metabolic fate of radiolabeled LTB4 during a 2-hr intrapleural incubation in rats with acute carrageenan pleurisy. After injection of 0.2 ml of 1% sodium carrageenan (Viscarin), inflammation was allowed to develop for 4 hr. A small polyethylene cannula was then inserted into the chest, and 0.1 microCi of [14C]LTB4 was injected into the chest. Samples for radioactivity determination were taken at 0, 1, 2, 3, 4, 5, 7, 10, 15, 20, 30, 45, 60, 90 and 120 min via the cannula, and at 120 min the entire content of the chest was collected. The half-life for the disappearance of radioactivity from the chest was 45.8 +/- 3.5 min. The 120-min samples were treated with acetone to precipitate protein and extracted with Sep-Paks. The extracts were analyzed by reversed phase high performance liquid chromatography using an ultraviolet detector set at 269 nm and a radioactivity detector. An additional experiment was run using multi-[3H]LTB4, and the only major metabolites detected were omega-hydroxylated compounds. It can be concluded from these results that LTB4 is relatively stable in vivo and could be present for long enough at the inflammatory site to have an influence upon inflammatory cell migration.

Degradation of membrane phospholipids in the cultured human astroglial cell line UC-11MG during ATP depletion.

The exposure of brain cells to adverse conditions, such as ATP depletion, induces the degradation of membrane phospholipids and the accumulation of free fatty acids. We have investigated the mechanism of membrane breakdown in an in vitro cell injury model. Confluent cells from the human astroglial cell line UC-11MG were treated with sodium iodoacetate to deplete their intracellular ATP. Large amounts of saturated (palmitic acid) and unsaturated (oleic, linoleic and arachidonic acid) free fatty acids as well as diacylglycerols containing prelabeled fatty acids were released from the cells prior to the loss of plasma membrane integrity. The capacity of the cells to reincorporate free fatty acid into membrane phospholipids decreased in parallel with the loss of intracellular ATP, indicating the failure of the acyltransferase pathway. The addition of the phospholipase A2 inhibitors manoalide, mepacrine, or U-26384, or the phospholipase C inhibitor U-73122, reduced the severity of cell injury, but did not maintain cell viability. The addition of a battery of protease inhibitors with or without the phospholipase inhibitors had no protective effect. These results suggest that the activation of phospholipases A2 and C coupled with the loss of the reacylation process lead to the breakdown of membrane components during lethal cell injury.

Lack of effect of postinjury treatment with methylprednisolone or tirilazad mesylate on the increase in eicosanoid levels in the acutely injured cat spinal cord.

Methylprednisolone (MP) improves motor recovery in spinal cord-injured patients when administered in a 24 h intensive high dose regimen beginning within 8 h after spinal cord injury (SCI). The rationale for this regimen has been based upon the need for high doses (i.e., 30 mg/kg initial IV dose) to inhibit posttraumatic lipid peroxidation (LP) in the injured spinal segment. However, injury also triggers the immediate calcium-mediated activation of phospholipase A2 (PLA2), the release of arachidonic acid, and the enzymatic formation of potentially deleterious prostaglandins (PGE2 alpha, PGE2), thromboxane A2 (TXA2), and leukotrienes (LTs). Thus, in view of the glucocorticoid receptor-mediated inhibition of PLA2 that underlies much of MP's antiinflammatory actions, an additional neuroprotective mechanism may relate to an inhibition of eicosanoid formation. Using the cat spinal cord compression model (180g x 5 min at L3; Na pentobarbitol anesthesia), we examined whether 30 min postinjury dosing with MP (30 mg/kg IV) could attenuate spinal tissue eicosanoid levels measured by enzyme immunoassay at 1 h (Experiment 1). Pial blood flow was measured over the dorsal columns at the injury site using laser doppler flowmetry to monitor posttraumatic hyperperfusion as an index of the microvascular pathophysiology of acute SCI. In vehicle treated animals at 1 h postinjury, there was a significant increase in the tissue levels of PGF2 alpha (+290%), PGE2 (+260%), TXB2 (stable analog of TXA2, +126%), and LTB4 (+73%) in comparison to sham, uninjured animals. However, 6-keto-PGF1 alpha (stable analog of prostacyclin or PGI2) and LTC4 did not increase. Methylprednisolone did not reduce the increase in eicosanoid production. In the case of LTB4 and LTC4, MP actually increased the levels further. In addition, we examined the effects of a double dose MP regimen (30 mg/kg IV at 30 min plus 15 mg/kg IV at 2.5 h postinjury) on spinal cord eicosanoid levels at 4 h postinjury (Experiment 2). At 4 h postinjury, significant increases in PGF2 alpha, PGE2, TXB2, and 6-keto-PGF1 alpha were observed, and with the exception of PGE2, no MP attenuation of the increased eicosanoids was seen. These results fail to provide evidence that postinjury administration of high dose MP exerts a significant anti-PLA2 action. On the other hand, MP effectively inhibited secondary spinal cord pial hyperperfusion, which is believed to be largely mediated by free radical-lipid peroxidative mechanisms. Thus, it seems likely that the protective action of MP on the acute microvascular pathophysiology of SCI is mediated by its well-documented effects on posttraumatic LP.(ABSTRACT TRUNCATED AT 400 WORDS)

The effects of kainic acid lesions on locomotor responses to haloperidol and clozapine.

Spontaneous and amphetamine-elicited locomotor activity in rats is reduced by most clinically effective antipsychotic drugs. We have recently demonstrated that intracerebroventricular infusion of kainic acid (KA), which produces cell loss in the hippocampus and other limbic-cortical brain regions, increases spontaneous and amphetamine-elicited locomotion. The present study determined if KA lesions alter the suppressive effects of the antipsychotic drugs, haloperidol and clozapine, on spontaneous and amphetamine-elicited locomotor behavior. Young adult male rats (70 days of age) received intracerebroventricular infusions of vehicle or KA, which produced hippocampal pyramidal cell loss in each rat and more variable cell loss or gliosis in the amygdala, piriform cortex, and laterodorsal thalamus. Thirty days post-surgery, lesioned and control rats were tested once a week for locomotor responses to drug treatments. As observed previously, spontaneous locomotor activity and hyperactivity elicited by amphetamine (1.50 mg/kg s.c.) were greater in lesioned animals than controls. In addition, the level of spontaneous activity and/or amphetamine-elicited hyperlocomotion observed in lesioned rats after haloperidol treatment (0.13, 0.35, or 1.50 mg/kg s.c.) was greater than that found in controls. Locomotor responses to low (6.30 mg/kg) and moderate doses of clozapine (20 mg/kg) were similar in lesioned and control rats, although lesioned rats were more active than controls following the administration of a high dose of clozapine (30 mg/kg). These data indicate that the hyperactivity associated with limbic-cortical lesions may be insensitive to reversal by haloperidol, yet uniquely sensitive to suppression by clozapine.

Contribution of leukotriene B4 to airway inflammation and the effect of antagonists.

Inhalation of aerosols of ovalbumin in sensitized guinea pigs produced a marked, bronchoalveolar eosinophilia 24 hr after challenge. The lung eosinophilia was not prevented by the cyclooxygenase inhibitors, indomethacin or PAF antagonists (WEB-2086 and L-652731) but was inhibited by methylprednisolone, the 5-LO inhibitor, U-66858 and a series of structural analogs of LTB4, U-75302, U-77692, U-75485 and U-78489. The effectiveness of LTB4 antagonists but not PAF antagonists in vivo was consistent with in vitro studies in which LTB4 was shown to be far more chemotactic than PAF for guinea pig eosinophils. LTB4 elicited maximal directional migration of guinea pig eosinophils at concentrations from 10(-7) M to 10(-9) M while PAF showed no effect over the same concentration range. The structural analogs of LTB4 were shown to inhibit LTB4 induced chemotaxis of guinea pig eosinophils and produced a dose-related inhibition of binding of LTB4 to guinea pig eosinophil membranes. To add further proof to the hypothesis that LTB4 contributed to the antigen-induced lung eosinophilia we attempted to measure LTB4 release into BAL fluid immediately after and at various time points up to 24 hr after antigen inhalation. However, using a sensitive radioimmunoassay (detection limit 10 pg/ml) very low levels of LTB4 (24.9-67.9 pg/ml) or its metabolite, 20-OH LTB4 (24.9-98.2 pg/ml) were detected in BAL fluid and these levels did not increase significantly following antigen provocation. Inhalation of LTB4 aerosols in unsensitized Brown-Norway rats or inhalation of aerosols of ovalbumin in sensitized Brown-Norway rats also produced a marked "late-phase" eosinophil-rich influx of inflammatory cells into the lungs. The lung eosinophilia in the rat was prevented by two structurally unrelated leukotriene B4 (LTB4) antagonists, U-75302 and Ly255283. These data implicate LTB4 as a mediator of allergen-induced bronchopulmonary eosinophilia. Leukotriene B4 antagonists may provide leads for the development of compounds which inhibit the chronic airway inflammation associated with asthma in man.

Prevention of adhesion formation with use of sodium hyaluronate-based bioresorbable membrane in a rat model of ventral hernia repair with polypropylene mesh--a randomized, controlled study.

BACKGROUND: There is a high incidence of adhesions after ventral hernia repair with polypropylene mesh. Hyaluronic acid (HA)-based membrane has been shown to reduce the incidence of adhesions in the absence of prosthetic mesh. The purpose of this study was to determine the effect of HA membrane on the quantity and grade of adhesions and its effect on strength of repair after abdominal wall repair with polypropylene mesh. METHODS: In 61 rats a full-thickness abdominal wall defect (excluding skin) was created, and a section of small bowel was abraded. The animals were randomized, receiving either HA membrane to cover the viscera or no membrane. The fascial defect was repaired with polypropylene mesh. Equal numbers of animals from each group were killed at 4 weeks and 8 weeks after surgery. Adhesion severity and percentage of mesh surface covered with adhesions were estimated. Tensile strength between mesh and muscle from each animal was measured. Sections of the mesh-muscle interface were examined histologically and measured for thickness and graded for inflammation and fibrosis. RESULTS: Fifty-five animals survived until the end point. Animals in the HA membrane group had a significant reduction in (1) grade of adhesions between small bowel and mesh at 4 weeks (P = .009) and 8 weeks (P = .000001), (2) grade of adhesions between colon and mesh at 8 weeks (P = .00003), and (3) percentage of mesh covered with adhesions at 4 weeks (P = .01) and 8 weeks (P = .0000002). There was no difference between the 2 groups in tensile strength of the repairs, tissue thickness, degree of inflammation, or degree of fibrosis. CONCLUSIONS: HA membrane reduces the quantity and grade of adhesions of both small and large bowel, to polypropylene mesh in a rat model of ventral hernia repair, without compromising strength of the repair.

Straight ileoanal anastomosis v ileal pouch--anal anastomosis after colectomy and mucosal proctectomy.

The postoperative results of 50 patients who underwent straight ileoanal anastomosis after total colectomy and mucosal proctectomy were compared with those of 74 patients who underwent ileal pouch--anal anastomosis. No deaths occurred. Of the straight ileoanal anastomoses, 32% failed because of sepsis or diarrhea and necessitated abdominal ileostomy; only 1.3% failed in the pouch-anal group (P less than .05). Stool frequency among patients followed up for three months or more (straight ileoanal, n = 30; pouch-anal, n = 33) was less in the pouch-anal group (mean +/- SEM, 7 +/- 1 stools per 24 hours) than in the straight ileoanal group (11 +/- 1/24 hr, P less than .01). Major nocturnal incontinence was also less in the pouch-anal group than in the straight ileoanal group (0% v 20%), and patient satisfaction was better, as measured on a scale of 1 (very poor functional result) to 10 (excellent result) (pouch-anal score, 9; straight ileoanal score, 6; P less than .02). We concluded that ileal pouch-anal anastomosis resulted in less diarrhea, better continence, and an improved quality of life when compared with straight ileoanal anastomosis.

Effects of the lipid peroxidation inhibitor tirilazad mesylate (U-74006F) on gerbil brain eicosanoid levels following ischemia and reperfusion.

The present study measured the production of eicosanoids in the gerbil brain during early reperfusion after either a 3-h unilateral carotid occlusion (UCO, model of focal ischemia) or a 10-min bilateral carotid occlusion (BCO, model of global ischemia). Arachidonic acid (AA) metabolites were examined to determine if pretreatment with the 21-aminosteroid lipid peroxidation inhibitor U-74006F (tirilazad mesylate) could influence postreperfusion synthesis of brain eicosanoids. In the 3-h UCO focal ischemia model, there was an early (5-min) postreperfusion elevation in brain levels of PGF2 alpha, TXB2 and LTC4 (P < 0.05 vs. sham for all three eicosanoids). LTB4 also rose but not significantly. On the other hand, PGE2 and 6-keto-PGF1 alpha tended to decrease during ischemia and at 5-min postreperfusion (P < 0.05 vs. sham for PGE2). Pretreatment with known neuroprotective doses of U-74006F in this model (10 mg/kg i.p. 10 min before and again immediately upon reperfusion) did not affect the increase in PGF2 alpha or TXB2 but significantly blunted the elevations in LTC4 and LTB4. The postreperfusion decrease in PGE2 was also attenuated. In the 10-min BCO global ischemia model, there was also an increase in each of the measured eicosanoids, except LTB4, at 5 min after reperfusion. Pretreatment with U-74006F (10 mg/kg i.p. 10 min before ischemia) selectively decreased the rise in LTC4 but did not significantly affect the other eicosanoids. In contrast, the antioxidant actually caused a significant enhancement of the postreperfusion increase in PGE2 vs. vehicle-treated animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Maturation of locomotor and Fos responses to the NMDA antagonists, PCP and MK-801.

Antagonists at the N-methyl-D-aspartate (NMDA)-type glutamate receptor, such as phencyclidine (PCP) and dizocilpine (MK-801), are well-known to evoke increases in locomotor activity in adult rats and mice. However, little is known about the effects of NMDA antagonists on locomotor activity as a function of development. The present study examined locomotor responses to PCP or MK-801 in male rats of varying ages and found that prepubertal rats were more sensitive to the locomotor-elevating effects of PCP (1.5 mg/kg and 3. 0 mg/kg, s.c.) than were adults. Locomotor responses to MK-801 (0.1 and 0.2 mg/kg, s.c.) were not dependent on age. The age-dependent response to PCP may be related to developmental events in the motor cortex, since more Fos-immunoreactive neurons were observed in the motor cortex of prepubertal animals after PCP administration relative to adult animals. An opposite pattern of age-dependent Fos responses was observed in the posterior retrosplenial cortex. The results suggest that locomotor responses to NMDA antagonists can be influenced in an age- and drug-dependent manner and that maturational events in the motor cortex may modify responses to PCP.