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1.
Water Res ; 149: 120-129, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30423503

RESUMO

Evolutionary computation has been applied to predict the occurrence of massive cyanobacteria proliferations; in the present study, this tool was further used to explore the factors responsible for maintaining picocyanobacterial dominance. Aiming to increase the understanding of factors that promote dominance of picocyanobacteria in tropical reservoirs, we chose two reservoirs used for water supplies located in different regions of Brazil and subjected to climate changes such as warmer winters that intensify water column stratification and prolonged dry seasons that cause water level decreases. This study focused on the diagnosis of the relationships among picocyanobacteria (1-2 µm), zooplankton and environmental variables using evolutionary computation. The integrated data analysis performed here was very successful in elucidating the dynamics of picocyanobacterial density variation influenced by both abiotic and biotic factors by the modeling approach. Relative water column stability - RWCS and electrical conductivity were highlighted as the most important environmental drivers for picocyanobacterial peaks. Hybrid Evolutionary Analysis (HEA) models for the two reservoirs indicated for the first time in the literature that rotifers, small-sized cladocerans and copepods (mainly nauplii) can directly or indirectly control picocyanobacteria in tropical mesotrophic reservoirs, depending on RWCS conditions and electrical conductivity. However, this control is modulated by pH, water transparency and water temperature thresholds.


Assuntos
Copépodes , Cianobactérias , Rotíferos , Animais , Brasil , Zooplâncton
2.
Xenobiotica ; 39(12): 964-77, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19925385

RESUMO

To enable clinical development of ibudilast for new indications, its pharmacokinetics were characterized in mice, rats, rabbits, dogs, cynomolgus monkeys, and minipigs. Animal pharmacokinetics were compared with a separate study in healthy volunteers. Following oral dosing, the dose-normalized area under the curve (AUC) (DN-AUC(24h)) in humans is 896 ((ng*h ml(-1))/(mg kg(-1))), and in animals ranges from 0.3 to 87. The variability among species cannot be explained by intrinsic clearance, which in intravenous dosing experiments shows only moderate interspecies variation (13-41 l h(-1) m(-2)). A portal vein rat pharmacokinetics model suggested that differences in first-pass gut clearance may explain some of the interspecies variation in oral bioavailability. Ibudilast shows auto-induction of metabolism in some animals, but not in humans. Plasma protein binding in humans and some animals is greater than or equal to 95%. The primary metabolite 6,7-dihyrdodiol-ibudilast is measurable and has been quantitated in plasma from animals and humans. Finally, biodistribution studies show that ibudilast distributes rapidly, extensively, and reversibly to the central nervous system.


Assuntos
Piridinas/farmacocinética , Administração Oral , Animais , Proteínas Sanguíneas/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Injeções Intravenosas , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Especificidade de Órgãos/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Piridinas/administração & dosagem , Piridinas/sangue , Piridinas/química , Especificidade da Espécie
3.
Braz J Biol ; 67(2): 251-62, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17876435

RESUMO

The Imboassica lagoon, located in the Municipality of Macaé (RJ), is separated from the sea by a sand bar, and its surroundings are partially occupied by residential areas. This coastal lagoon has undergone environmental degradation due to sewage input and artificial sand bar openings. The temporal and spatial variation of environmental variables and zooplankton were studied monthly for four years. There were five artificial openings of the sand bar during the period of study, mostly in the rainy season. Besides osmotic changes, these events caused the drainage of the water of the lagoon into the sea, loss of total organic nitrogen, and an increase of total phosphorus. The zooplankton community of Imboassica lagoon included freshwater and marine taxa, holoplanktonic, meroplanktonic and nectobenthonic forms. Polychaeta, Bivalvia and Gastropoda larvae, and the taxa of Rotifera Hexarthra spp., Lecane bulla, Synchaeta bicornis, nauplii of Cyclopoida and Calanoida copepods were considered constant taxa. Distinct zooplankton assemblages were found during zooplankton spatial surveys in oligohaline and mesohaline conditions. The successful zooplankton populations were either favored by the disturbance of the sand bar opening, such as the veligers of the gastropod Heleobia australis, or capable of fast recovery after the closing of the sand bar, during the succession from a marine into an oligohaline environment, such as Hexarthra spp.. Such populations seemed well adapted to the stress conditions usually found in the lagoon due to osmotic changes, column mixing, nutrient input, and high fish predation pressure. Rare species in the community, such as Moina minuta, presented population increases all over the lagoon under oligohaline conditions.


Assuntos
Monitoramento Ambiental , Esgotos , Zooplâncton/classificação , Animais , Brasil , Densidade Demográfica , Dinâmica Populacional , Estações do Ano , Zooplâncton/fisiologia
4.
Int J Oral Maxillofac Surg ; 36(12): 1153-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17629458

RESUMO

The external traction hooks of the intraoral splint used to control traction forces applied to the maxilla with the rigid external distraction system represent a major barrier to surgical procedures. The purpose of this article is to introduce a removable intraoral splint with locking attachments that can be placed post-surgically immediately before distraction, facilitating surgery and consequently reducing the operative time. Fifteen cleft lip and palate patients underwent maxillary distraction osteogenesis using a rigid external distraction device in combination with the proposed removable splint that was fixed onto the maxillary teeth to provide anchorage. Initial records showed severe maxillary hypoplasia and negative overjet. The removable splint was fabricated using 1.5-mm diameter stainless-steel rigid orthodontic wires soldered to the locking attachments (Y&B Products LP, Chiang Mai, Thailand), making possible its placement post-surgically. Stable splint fixation was achieved prior to the distraction procedure and the desired treatment goals were reached. No complications inserting or removing the splint post-surgically, including pain or discomfort, were observed. The use of the removable splint with locking attachments has proved to be a highly effective fixation approach to manage the severely hypoplastic maxilla, eliminating lip constraints resulting from scarring, and allowing for easier, more deliberate and careful dissection.


Assuntos
Maxila/cirurgia , Placas Oclusais , Osteogênese por Distração/instrumentação , Osteotomia de Le Fort/métodos , Adolescente , Adulto , Criança , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Humanos , Má Oclusão/cirurgia , Osteotomia de Le Fort/instrumentação
5.
Braz. j. biol ; 67(2): 251-262, May 2007. ilus, graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-459997

RESUMO

The Imboassica lagoon, located in the Municipality of Macaé (RJ), is separated from the sea by a sand bar, and its surroundings are partially occupied by residential areas. This coastal lagoon has undergone environmental degradation due to sewage input and artificial sand bar openings. The temporal and spatial variation of environmental variables and zooplankton were studied monthly for four years. There were five artificial openings of the sand bar during the period of study, mostly in the rainy season. Besides osmotic changes, these events caused the drainage of the water of the lagoon into the sea, loss of total organic nitrogen, and an increase of total phosphorus. The zooplankton community of Imboassica lagoon included freshwater and marine taxa, holoplanktonic, meroplanktonic and nectobenthonic forms. Polychaeta, Bivalvia and Gastropoda larvae, and the taxa of Rotifera Hexarthra spp., Lecane bulla, Synchaeta bicornis, nauplii of Cyclopoida and Calanoida copepods were considered constant taxa. Distinct zooplankton assemblages were found during zooplankton spatial surveys in oligohaline and mesohaline conditions. The successful zooplankton populations were either favored by the disturbance of the sand bar opening, such as the veligers of the gastropod Heleobia australis, or capable of fast recovery after the closing of the sand bar, during the succession from a marine into an oligohaline environment, such as Hexarthra spp.. Such populations seemed well adapted to the stress conditions usually found in the lagoon due to osmotic changes, column mixing, nutrient input, and high fish predation pressure. Rare species in the community, such as Moina minuta, presented population increases all over the lagoon under oligohaline conditions.


A Lagoa Imboassica, localizada no Município de Macaé (RJ), é separada do mar por uma barra de areia e se encontra cercada parcialmente por áreas residenciais. Esta lagoa costeira tem sofrido intensa degradação ambiental devido à afluência de esgotos domésticos e a aberturas artificiais da barra de areia. Neste estudo foram acompanhadas, mensalmente ao longo de quatro anos, as variações temporais e espaciais de variáveis ambientais e do zooplâncton. Durante o período estudado foram realizadas cinco aberturas artificiais da barra de areia, sendo a maioria efetuada na época chuvosa. Além das alterações osmóticas, estas aberturas causaram a drenagem da água da lagoa para o mar, diminuição dos valores de nitrogênio total e aumento da concentração de fósforo total. A comunidade zooplanctônica da lagoa incluiu táxons de água doce e marinhos e formas holoplanctônicas, meroplanctônicas e nectobentônicas. Foram considerados constantes na comunidade larvas de Polychaeta, Bivalvia e Gastropoda, os táxons de Rotifera Hexarthra spp., Lecane bulla, Synchaeta bicornis e naúplios de copépodos Cyclopoida e Calanoida. Durante as amostragens espaciais ao longo de todo o corpo da lagoa em condições oligohalinas e mesohalinas foram encontradas distintas assembléias zooplanctônicas. As populações zooplanctônicas que apresentaram maior ocorrência foram aquelas aparentemente favorecidas pelo distúrbio causado pelas aberturas de barra, tais como véligers do gastrópode Heleobia australis, ou capazes de recuperação rápida após o fechamento da barra de areia, durante a transição de um ambiente marinho para um oligohalino, como Hexarthra spp.. Tais populações se mostraram bem adaptadas às condições de "stress" usualmente encontradas na lagoa devido a mudanças osmóticas, mistura da coluna d'água, aporte contínuo de nutrientes e alta pressão de predação por peixes. As espécies consideradas como raras na comunidade zooplanctônica, como Moina minuta apresentaram maiores...


Assuntos
Animais , Monitoramento Ambiental , Esgotos , Zooplâncton/classificação , Brasil , Densidade Demográfica , Dinâmica Populacional , Estações do Ano , Zooplâncton/fisiologia
6.
Braz. j. biol ; 62(4b): 835-846, Nov. 2002. tab, graf
Artigo em Inglês | LILACS | ID: lil-339383

RESUMO

Non-treated sewage disposal is one of the main impacts to which Imboassica Lagoon has been subjected. The aim of this study was to evaluate the effect of a potential increase in the artificial enrichment on the environmental conditions and zooplankton of this system. To this end, an experimental study was conducted in mesocosms where nutrients were added daily. Bacterial numbers, chlorophyll-a, and picoplanktonic cyanobacteria densities showed an increase with the availability of nutrients. Bacterio- and phytoplankton seemed to be regulated by the rotifers Brachionus rotundiformis and Hexarthra brandorffi


Assuntos
Animais , Eutrofização , Zooplâncton , Análise de Variância , Brasil , Clorofila , Cianobactérias , Monitoramento Ambiental , Esgotos , Poluição da Água
7.
Braz J Biol ; 62(4B): 835-46, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12659035

RESUMO

Non-treated sewage disposal is one of the main impacts to which Imboassica Lagoon has been subjected. The aim of this study was to evaluate the effect of a potential increase in the artificial enrichment on the environmental conditions and zooplankton of this system. To this end, an experimental study was conducted in mesocosms where nutrients were added daily. Bacterial numbers, chlorophyll-a, and picoplanktonic cyanobacteria densities showed an increase with the availability of nutrients. Bacterio- and phytoplankton seemed to be regulated by the rotifers Brachionus rotundiformis and Hexarthra brandorffi.


Assuntos
Eutrofização , Zooplâncton , Análise de Variância , Animais , Brasil , Clorofila/análise , Clorofila A , Cianobactérias , Monitoramento Ambiental , Esgotos , Poluição da Água/prevenção & controle
8.
Braz. j. biol ; 62(4)2002.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467679

RESUMO

Non-treated sewage disposal is one of the main impacts to which Imboassica Lagoon has been subjected. The aim of this study was to evaluate the effect of a potential increase in the artificial enrichment on the environmental conditions and zooplankton of this system. To this end, an experimental study was conducted in mesocosms where nutrients were added daily. Bacterial numbers, chlorophyll-a, and picoplanktonic cyanobacteria densities showed an increase with the availability of nutrients. Bacterio- and phytoplankton seemed to be regulated by the rotifers Brachionus rotundiformis and Hexarthra brandorffi.


O despejo de esgoto não tratado é um dos principais impactos aos quais a Lagoa Imboassica está submetida. O objetivo deste estudo foi avaliar o efeito de um aumento potencial no enriquecimento artificial das condições ambientais e do zooplâncton desse sistema. Para tanto, foi realizado estudo experimental em mesocosmos aos quais foram adicionados nutrientes diariamente. O número de bactérias e de cianobactérias picoplanctônicas e a clorofila-a apresentaram aumento com a disponibilidade de nutrientes. Bacterio- e fitoplâncton parecem ter sido regulados pelos rotíferos Brachionus rotundiformis e Hexarthra brandorffi.

9.
Medicina (B Aires) ; 61(2): 147-56, 2001.
Artigo em Espanhol | MEDLINE | ID: mdl-11374136

RESUMO

In Argentina the first Hantavirus Pulmonary Syndrome (HPS) cases were characterized in 1995. Since then, Argentina is the country with the highest number of notified cases in South America. The disease is distributed in Northern, Southern and Central regions of the country, being Buenos Aires the most affected province from the Central region. In this study, we present seasonal and geographical distribution of HPS cases in Buenos Aires province, the association with diverse viral lineages and the serological characteristics of hantavirus infection in the period from 1997 up to the first semester of the year 2000. An increase in the number of HPS cases was observed up to 1999 and a gradual mortality decrease in the whole period. The cases occurred between spring and autumn, with a maximum peak in summer. The serological response was studied in 58 HPS confirmed cases at different times after the onset of symptoms. The cases were distributed between 27 localities, in two different directions from the city of Buenos Aires: South-southwest and North-northeast. More than 52% of the cases occurred in La Plata and neighboring localities. The viral genomes from 39 cases were all characterised as Andes virus (AND): AND Cent Plata 16%; AND Cent 21% and AND Cent Bs.As. 60%. Andes virus lineages only cocirculated in La Plata city. These results will contribute to establish a risk map leading to the implementation of improved strategies of prevention.


Assuntos
Síndrome Pulmonar por Hantavirus/epidemiologia , Orthohantavírus/genética , Anticorpos Antivirais/sangue , Argentina/epidemiologia , Seguimentos , Genoma Viral , Orthohantavírus/classificação , Orthohantavírus/imunologia , Síndrome Pulmonar por Hantavirus/sangue , Síndrome Pulmonar por Hantavirus/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Medicina [B Aires] ; 61(2): 147-56, 2001.
Artigo em Espanhol | BINACIS | ID: bin-39546

RESUMO

In Argentina the first Hantavirus Pulmonary Syndrome (HPS) cases were characterized in 1995. Since then, Argentina is the country with the highest number of notified cases in South America. The disease is distributed in Northern, Southern and Central regions of the country, being Buenos Aires the most affected province from the Central region. In this study, we present seasonal and geographical distribution of HPS cases in Buenos Aires province, the association with diverse viral lineages and the serological characteristics of hantavirus infection in the period from 1997 up to the first semester of the year 2000. An increase in the number of HPS cases was observed up to 1999 and a gradual mortality decrease in the whole period. The cases occurred between spring and autumn, with a maximum peak in summer. The serological response was studied in 58 HPS confirmed cases at different times after the onset of symptoms. The cases were distributed between 27 localities, in two different directions from the city of Buenos Aires: South-southwest and North-northeast. More than 52


of the cases occurred in La Plata and neighboring localities. The viral genomes from 39 cases were all characterised as Andes virus (AND): AND Cent Plata 16


; AND Cent 21


and AND Cent Bs.As. 60


. Andes virus lineages only cocirculated in La Plata city. These results will contribute to establish a risk map leading to the implementation of improved strategies of prevention.

11.
Biorheology ; 35(1): 1-16, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10211126

RESUMO

In a developing lamb model, we have used hydrothermal isometric tension (HIT) techniques to assess collagen crosslink stability and its contribution to the mechanical properties of the pericardium. Strip samples of tissue were either: (i) heated to a 90 degrees C isotherm or (ii) heated in 5 degrees C increments between 60-90 degrees C and then 93 and 97 degrees C isotherms. The half-life of stress relaxation associated with peptide bond hydrolysis (t1/2) was calculated at each isotherm. The activation energy, Eact, for the hydrolysis-associated relaxation process was also calculated using the data from the stepwise HIT tests--a technical improvement which significantly reduces the experimental time required to develop statistically valid measurements. Crosslinking in the pericardium increased during development and was demonstrated both by thermoelasticity and by resistance to enzymatic solubilization. We observed greater conversation to thermally stable crosslinks upon maturation, the ratio of the NaBH4-stabilized/unstabilized half-lives peaking at 21 days postnatal. Whereas tissue from lambs (119 day fetal, and 3 day and 21 day postpartum) showed an early maximum and rapid decay of force, NaBH4 stabilization significantly increased thermal stability and yielded profiles similar to those in adult tissue.


Assuntos
Colágeno/fisiologia , Desenvolvimento Embrionário e Fetal/fisiologia , Contração Isométrica , Contração Miocárdica , Pericárdio/embriologia , Animais , Temperatura Alta , Técnicas In Vitro , Modelos Biológicos , Reologia , Ovinos
13.
Am J Otol ; 4(4): 288-91, 1983 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6344649

RESUMO

An incidence of postoperative infection of up to 15 percent has been reported following middle ear ventilation tube surgery. This rate of complication would be considered unacceptable following most other operative procedures. A controlled prospective study of 107 children undergoing tympanostomy and tube surgery over a 1-year period was undertaken. Subjects were randomly assigned to receive antibiotic-steroid otic drops at the time of surgery and for 1 week afterward, oral ampicillin for 24 hours preceding and 3 days following surgery, or no prophylactic treatment. The overall infection rate within four weeks of surgery was 12 percent. Purulent otorrhea occurred in 18 percent of those receiving no prophylactic treatment, in 13 percent receiving ampicillin, and in 6 percent receiving antibiotic-steroid otic drops. Postoperative infection was related to preoperative history of status otitis media and to previous placement of ventilation tubes.


Assuntos
Infecções/etiologia , Ventilação da Orelha Média/efeitos adversos , Adolescente , Adulto , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Combinação de Medicamentos/uso terapêutico , Feminino , Humanos , Hidrocortisona/uso terapêutico , Lactente , Infecções/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Neomicina/uso terapêutico , Otite Média/cirurgia , Polimixina B/uso terapêutico , Estudos Prospectivos , Distribuição Aleatória , Infecções Respiratórias/complicações
17.
Arch Gen Psychiatry ; 32(6): 780-3, 1975 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1169046

RESUMO

Both a sleep-wakefulness cycle and a basic rest-activity cycle were observed in 20 normal infants left undisturbed for ten hours following birth. Behavioral wakefulness occurred immediately following delivery and in between sleep periods despite the lack of feeding and other intervention. Medication given to mothers during labor resulted in decreased amounts of infant wakefulness and increased amounts of quiet (non rapid eye movement) sleep.


Assuntos
Relógios Biológicos , Recém-Nascido , Ovinos/fisiologia , Vigília/fisiologia , Animais , Relógios Biológicos/efeitos dos fármacos , Diazepam/farmacologia , Feminino , Humanos , Trabalho de Parto , Meperidina/farmacologia , Gravidez , Prometazina/farmacologia , Secobarbital/farmacologia , Sono/efeitos dos fármacos , Vigília/efeitos dos fármacos
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