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1.
Proc Biol Sci ; 290(2001): 20230584, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37339745

RESUMO

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.


Assuntos
Antozoários , Bass , Animais , Estações do Ano , Peixes , Recifes de Corais , Pesqueiros , Envelhecimento
2.
Lett Appl Microbiol ; 76(3)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36906280

RESUMO

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.


Assuntos
COVID-19 , Vírus , Humanos , SARS-CoV-2 , Desinfecção/métodos , Detergentes/farmacologia , Tato , COVID-19/prevenção & controle , Água
3.
J Fish Biol ; 90(6): 2452-2461, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28382708

RESUMO

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.


Assuntos
Peixes/crescimento & desenvolvimento , Organismos Hermafroditas , Maturidade Sexual , Animais , Tamanho Corporal , Feminino , Pesqueiros , Peixes/anatomia & histologia , Peixes/fisiologia , Masculino , Caracteres Sexuais
4.
Int J Tuberc Lung Dis ; 20(9): 1219-25, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27510249

RESUMO

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.


Assuntos
Diagnóstico Tardio , Tuberculose/diagnóstico , Tuberculose/epidemiologia , População Urbana , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Cidades/epidemiologia , Feminino , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Portugal/epidemiologia , Estudos Retrospectivos , Análise Espacial , Análise de Sobrevida , Migrantes , Adulto Jovem
5.
J Fish Biol ; 88(5): 1856-69, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27021483

RESUMO

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.


Assuntos
Bass/crescimento & desenvolvimento , Reprodução , Processos de Determinação Sexual , Animais , Tamanho Corporal , Feminino , Pesqueiros , Gônadas/crescimento & desenvolvimento , Masculino , Micronésia , Estações do Ano , Maturidade Sexual , Temperatura
6.
J Fish Biol ; 85(3): 901-16, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25082347

RESUMO

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.


Assuntos
Perciformes/crescimento & desenvolvimento , Reprodução , Animais , Tamanho Corporal , Feminino , Gônadas/crescimento & desenvolvimento , Masculino , Micronésia , Membrana dos Otólitos/crescimento & desenvolvimento , Caracteres Sexuais , Maturidade Sexual
7.
J Fish Biol ; 84(2): 383-402, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24446696

RESUMO

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.


Assuntos
Perciformes/crescimento & desenvolvimento , Determinação da Idade pelo Esqueleto/veterinária , Animais , Tamanho Corporal , Análise por Conglomerados , Feminino , Longevidade , Masculino , Micronésia , Análise Multivariada , Perciformes/anatomia & histologia , Filogenia , Maturidade Sexual
8.
J Fish Biol ; 82(4): 1333-50, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23557310

RESUMO

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.


Assuntos
Bass/fisiologia , Reprodução , Maturidade Sexual , Distribuição por Idade , Animais , Bass/crescimento & desenvolvimento , Tamanho Corporal , Feminino , Masculino , Processos de Determinação Sexual , Comportamento Sexual Animal
10.
J Org Chem ; 66(23): 7666-75, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11701019

RESUMO

The reaction mechanisms of amino acids with a new class of fluorogenic reagents were investigated. The structures of colored and fluorescent species formed in these reactions were partially confirmed by experimental evidence. Reaction intermediates, C-N-C 1,3-dipoles derived from imines, were trapped with dipolarophiles in 3 + 2 cycloadditions to form spiropyrrolidines.


Assuntos
Aminoácidos/química , Indanos/química , Pirrolidinas/química , Compostos de Espiro/química
11.
Anal Biochem ; 295(1): 101-6, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11476550

RESUMO

A sensitive competitive method was developed for assessing the reactivity of compounds toward glutathione and toward thiols in general. The method employs the reaction of the fluorogenic reagent fluorescein-5-maleimide (FM) with glutathione (GSH) to generate a large increase in fluorescence emission. When the reaction is measured in the presence of a compound that competes with FM toward GSH, the rate constant for fluorescent product formation increases while the total amount of product formed at the end of the reaction decreases. These changes in the presence of a series of competitor concentrations allow one to calculate the rate constant of the reaction of the competitor with GSH. At 23 degrees C, pH 7.40 in PBS buffer the second-order rate constant of the FM-GSH reaction is k2 = (1.67 +/- 0.32) x 10(4) M(-1) x s(-1). Two GSH-reactive compounds were evaluated: the second-order rate constant for the reaction of PNU-27707 with GSH under our experimental conditions is k(i) = 5660 +/- 266 M(-1) x s(-1), while that of PNU-37802 is k(i) = 21,200 +/- 1600 M(-1) x s(-1). The method is easily adaptable to a high-throughput screening format.


Assuntos
Fluoresceínas/metabolismo , Corantes Fluorescentes/metabolismo , Glutationa/metabolismo , Compostos de Sulfidrila/metabolismo , Ligação Competitiva , Cumarínicos/química , Cumarínicos/metabolismo , Fluoresceínas/química , Fluorescência , Corantes Fluorescentes/química , Glutationa/química , Cinética , Compostos de Sulfidrila/química
12.
Ann Surg ; 233(3): 438-44, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11224634

RESUMO

OBJECTIVE: To compare the effectiveness and safety of low-dose unfractionated heparin and a low-molecular-weight heparin as prophylaxis against venous thromboembolism after colorectal surgery. METHODS: In a multicenter, double-blind trial, patients undergoing resection of part or all of the colon or rectum were randomized to receive, by subcutaneous injection, either calcium heparin 5,000 units every 8 hours or enoxaparin 40 mg once daily (plus two additional saline injections). Deep vein thrombosis was assessed by routine bilateral contrast venography performed between postoperative day 5 and 9, or earlier if clinically suspected. RESULTS: Nine hundred thirty-six randomized patients completed the protocol and had an adequate outcome assessment. The venous thromboembolism rates were the same in both groups. There were no deaths from pulmonary embolism or bleeding complications. Although the proportion of all bleeding events in the enoxaparin group was significantly greater than in the low-dose heparin group, the rates of major bleeding and reoperation for bleeding were not significantly different. CONCLUSIONS: Both heparin 5,000 units subcutaneously every 8 hours and enoxaparin 40 mg subcutaneously once daily provide highly effective and safe prophylaxis for patients undergoing colorectal surgery. However, given the current differences in cost, prophylaxis with low-dose heparin remains the preferred method at present.


Assuntos
Anticoagulantes/uso terapêutico , Colectomia/métodos , Enoxaparina/uso terapêutico , Heparina/uso terapêutico , Reto/cirurgia , Perda Sanguínea Cirúrgica , Canadá/epidemiologia , Método Duplo-Cego , Feminino , Humanos , Injeções Subcutâneas , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/prevenção & controle , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Hemorragia Pós-Operatória/epidemiologia , Estudos Prospectivos , Trombocitopenia/epidemiologia , Trombocitopenia/etiologia , Tromboembolia/epidemiologia , Tromboembolia/prevenção & controle , Trombose Venosa/epidemiologia , Trombose Venosa/prevenção & controle
13.
Eur J Pain ; 4(2): 185-93, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10957699

RESUMO

Both transcutaneous electrical nerve stimulation (TENS) and morphine are commonly used for relief of pain. Extensive research has been done on the effectiveness of each of these two methods for pain relief when given independently. However, very little literature exists examining the effectiveness of their combined use. Systemically administered morphine activates mu opioid receptors and when administered for prolonged periods results in analgesic tolerance. Low (4 Hz) and high (100 Hz) frequency TENS activate mu- and delta-opioid receptors, respectively, It is thus possible that TENS would be less effective in morphine-tolerant subjects. The current study investigated the effectiveness of high- and low-frequency TENS in the reversal of hyperalgesia in inflamed rats that were morphine-tolerant. Morphine tolerance was induced by subcutaneous implantation of morphine pellets over 10 days. Knee joint inflammation was induced by injection of kaolin and carrageenan into the knee joint cavity. Secondary heat hyperalgesia was tested by measuring the paw withdrawal latency to radiant heat (1) before pellet implantation (either morphine or placebo), (2) after pellet implantation and before inflammation, (3) after inflammation and (4) after TENS. Both high (100 Hz) and low (4 Hz) frequency TENS caused nearly 100% inhibition of secondary hyperalgesia in animals receiving placebo pellets. In contrast, the hyperalgesia in morphine-tolerant animals with knee joint inflammation was unaffected by low frequency TENS but fully reversed by high frequency TENS. These results suggest that patients who are tolerant to morphine may respond better to high frequency TENS than to low frequency TENS.


Assuntos
Hiperalgesia/tratamento farmacológico , Dependência de Morfina , Morfina/farmacologia , Entorpecentes/farmacologia , Estimulação Elétrica Nervosa Transcutânea/métodos , Animais , Carragenina , Tolerância a Medicamentos , Hiperalgesia/etiologia , Irritantes , Caulim , Masculino , Ratos , Ratos Sprague-Dawley , Receptores Opioides delta/fisiologia , Receptores Opioides mu/fisiologia , Medula Espinal/química , Medula Espinal/fisiologia , Sinovite/induzido quimicamente , Sinovite/complicações
14.
Brain Res Dev Brain Res ; 122(1): 91-5, 2000 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-10915909

RESUMO

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.


Assuntos
Maleato de Dizocilpina/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Locomoção/efeitos dos fármacos , Fenciclidina/farmacologia , Proteínas Proto-Oncogênicas c-fos/análise , Receptores de N-Metil-D-Aspartato/fisiologia , Fatores Etários , Animais , Genes Precoces/fisiologia , Giro do Cíngulo/química , Giro do Cíngulo/efeitos dos fármacos , Giro do Cíngulo/crescimento & desenvolvimento , Masculino , Córtex Motor/química , Córtex Motor/efeitos dos fármacos , Córtex Motor/crescimento & desenvolvimento , Ratos , Ratos Sprague-Dawley , Maturidade Sexual/fisiologia
16.
Transplantation ; 67(11): 1418-25, 1999 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10385079

RESUMO

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.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Cadeias alfa de Integrinas , Integrinas/biossíntese , Linfócitos T Citotóxicos/metabolismo , Animais , Antígenos CD , Estabilidade de Medicamentos , Humanos , Transplante de Rim/patologia , Ativação Linfocitária , Teste de Cultura Mista de Linfócitos , Camundongos , Subpopulações de Linfócitos T/imunologia , Fator de Crescimento Transformador beta/fisiologia , Transplante Homólogo/patologia
17.
Dis Colon Rectum ; 42(2): 174-9, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10211492

RESUMO

PURPOSE: The aim of this study was to determine if local injection of bupivacaine after hemorrhoidal banding causes a decrease in pain and in the incidence of associated symptoms. METHODS: After hemorrhoidal banding, patients were randomly assigned to receive a local injection of bupivacaine with 1:200,000 epinephrine, an injection of normal saline, or no injection, just superior to each band. Pain was graded by the patient and by the study nurse within 30 minutes, and any associated symptoms were recorded. At intervals 6, 24, and 48 hours postbanding, the patient recorded pain, limitation of activities, and analgesic requirements. Associated symptoms while at home were recorded. RESULTS: Of 115 patients studied, 42 received bupivacaine injection, 42 received normal saline injection, and 31 received no injection. In patients receiving bupivacaine compared with no injection, within 30 minutes postbanding there was a significant reduction in pain graded by the patient (P = 0.000002) and by the nurse (P = 0.000005) and a significant reduction in incidence of nausea (P = 0.01) and shaking (P = 0.008). However, in the bupivacaine group compared with the other two groups, at the intervals of 6, 24, and 48 hours postbanding there was no sustained reduction in the severity of pain and no reduction in analgesic requirements or limitation of normal activities. In the week after banding, there was no difference between groups in symptoms of nausea, shaking, lightheadedness, urinary retention, or bleeding. CONCLUSIONS: Bupivacaine injection may be useful for reducing pain and associated symptoms long enough to tolerate a trip home from the outpatient department but does not show a sustained effect.


Assuntos
Anestésicos Locais/administração & dosagem , Bupivacaína/administração & dosagem , Hemorroidas/cirurgia , Epinefrina/administração & dosagem , Feminino , Humanos , Injeções , Ligadura/métodos , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/tratamento farmacológico , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos , Borracha
18.
Surgery ; 125(2): 211-6, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10026756

RESUMO

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.


Assuntos
Hérnia Ventral/cirurgia , Ácido Hialurônico , Enteropatias/prevenção & controle , Polipropilenos , Telas Cirúrgicas , Animais , Materiais Biocompatíveis , Modelos Animais de Doenças , Fibrose , Inflamação , Enteropatias/patologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Índice de Gravidade de Doença , Procedimentos Cirúrgicos Operatórios/métodos , Resistência à Tração , Fatores de Tempo , Aderências Teciduais/prevenção & controle , Resultado do Tratamento
19.
Psychopharmacology (Berl) ; 135(3): 270-8, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9498730

RESUMO

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.


Assuntos
Antipsicóticos/farmacologia , Clozapina/farmacologia , Agonistas de Aminoácidos Excitatórios/toxicidade , Haloperidol/farmacologia , Ácido Caínico/toxicidade , Atividade Motora/efeitos dos fármacos , Anfetamina/farmacologia , Animais , Inibidores da Captação de Dopamina/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley
20.
Am J Respir Cell Mol Biol ; 17(6): 757-66, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9409563

RESUMO

Increased microvascular permeability and mucosal edema are pathological features of airway inflammation in asthma. In this study, we investigated the characteristics of the edema response occurring in a model of antigen-induced lung inflammation in sensitized brown Norway rats and examined the effects of monoclonal antibodies (mAbs) to adhesion molecules on this response. Ovalbumin (OA) challenge-induced increases in lung permeability were determined by the leakage of 125I-labeled bovine serum albumin (BSA) into the extravascular tissues of the lungs 24 h after challenge in animals intravenously injected (prechallenge) with this tracer. Inflammatory cell infiltration into the alveolar space was determined by bronchoalveolar lavage (BAL). Mean extravascular plasma volume in the lung increased 233% as compared with control (P < 0.005) at 24 h and increased to 517% by 72 h. The 24-h edema response was completely inhibited by two oral doses (0.1 mg/kg) of dexamethasone 1 h before, and 7 h after, challenge. Intraperitoneal administration of the anti-rat ICAM-1 mAb 1A29, or anti-rat alpha4 integrin mAb TA-2 (2 mg/kg at 12 and 1 h before, and 7 h after, antigen challenge), significantly suppressed eosinophil infiltration into the alveolar space without inhibiting the enhanced microvascular leakage and lung edema. Determination of plasma antibody concentrations by ELISA of mouse IgG1 indicated that sufficient concentrations of the appropriate mAb were present to block alpha4- or ICAM-1-dependent adhesion. The results suggest that increases in microvascular permeability and plasma leakage occurred independently of eosinophil accumulation.


Assuntos
Antígenos CD/fisiologia , Antígenos/imunologia , Permeabilidade Capilar/imunologia , Molécula 1 de Adesão Intercelular/fisiologia , Hipersensibilidade Respiratória/patologia , Animais , Anticorpos Monoclonais/imunologia , Antígenos CD/imunologia , Líquido da Lavagem Broncoalveolar/citologia , Dexametasona/farmacologia , Integrina alfa4 , Pulmão/irrigação sanguínea , Edema Pulmonar/imunologia , Edema Pulmonar/patologia , Edema Pulmonar/prevenção & controle , Ratos , Hipersensibilidade Respiratória/imunologia
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