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2.
Nat Nanotechnol ; 6(1): 65-71, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21170041

RESUMO

Previous studies have shown that engineered nanomaterials can be transferred from prey to predator, but the ecological impacts of this are mostly unknown. In particular, it is not known if these materials can be biomagnified-a process in which higher concentrations of materials accumulate in organisms higher up in the food chain. Here, we show that bare CdSe quantum dots that have accumulated in Pseudomonas aeruginosa bacteria can be transferred to and biomagnified in the Tetrahymena thermophila protozoa that prey on the bacteria. Cadmium concentrations in the protozoa predator were approximately five times higher than their bacterial prey. Quantum-dot-treated bacteria were differentially toxic to the protozoa, in that they inhibited their own digestion in the protozoan food vacuoles. Because the protozoa did not lyse, largely intact quantum dots remain available to higher trophic levels. The observed biomagnification from bacterial prey is significant because bacteria are at the base of environmental food webs. Our findings illustrate the potential for biomagnification as an ecological impact of nanomaterials.


Assuntos
Compostos de Cádmio/análise , Cadeia Alimentar , Pseudomonas aeruginosa/metabolismo , Pontos Quânticos , Compostos de Selênio/análise , Tetrahymena thermophila/metabolismo , Microscopia Eletrônica de Transmissão e Varredura , Nanoestruturas/microbiologia , Tetrahymena thermophila/crescimento & desenvolvimento , Tetrahymena thermophila/microbiologia , Vacúolos
3.
Eur J Vasc Endovasc Surg ; 38(5): 560-4, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19703780

RESUMO

OBJECTIVES: Thoracic outlet syndrome has been well described in the population between 25 and 40 years of age, and is less frequently reported in those in the first two decades of life. The objective of this study was to review results with onset of TOS in the first two decades of life to determine type of presentation and outcomes from surgical intervention. METHODS AND MATERIALS: Charts of all patients in the first two decades of life, operated on for TOS between 1994 and 2006 were reviewed with follow-up by clinic visit and phone survey to assess the patients' current level of activity and relief from symptoms. RESULTS: Twelve patients were identified (13 operations), with a mean age of 16.8 years. Acute ischemic symptoms were the initial presentation for 38%, venous TOS in 24%, and neurogenic symptoms in 38%. All patients had symptom relief with surgery with a mean time to resolution of 10.9 weeks. All patients remained symptom free or improved at follow-up. CONCLUSIONS: Vascular TOS is much more common in TOS presenting in the first two decades of life. Surgical intervention for TOS in this population results in long-lasting symptom relief and should be considered for all subtypes of patients.


Assuntos
Síndrome do Desfiladeiro Torácico/cirurgia , Procedimentos Cirúrgicos Vasculares , Adolescente , Criança , Feminino , Humanos , Masculino , Estudos Retrospectivos , Inquéritos e Questionários , Síndrome do Desfiladeiro Torácico/complicações , Síndrome do Desfiladeiro Torácico/diagnóstico , Fatores de Tempo , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Adulto Jovem
4.
In Vitro Cell Dev Biol Anim ; 42(8-9): 248-54, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17163779

RESUMO

We have established well-differentiated, polarized cultures of monkey oviductal epithelium. Oviductal epithelial cells were isolated by protease digestion and plated on collagen-coated, porous cell culture inserts. About 5 d after plating, cells developed detectable transepithelial electrical resistance of up to 2000 Omega.cm(2) (an index of tight junction formation) and transepithelial voltages of up to 20 mV (an index of vectorial transepithelial ion transport). Measurements of short-circuit current in Ussing chambers indicated that active secretion of Cl was the major transepithelial active ion transport process, and that this was stimulated by elevation of either cAMP or Ca(i). Furthermore, estimates of the volume of mucosal liquid were consistent with Cl secretion mediating fluid secretion. Various microscopical methods showed that the cultures were densely ciliated and contained mature secretory cells. Transport across the oviductal epithelium determines the composition of the oviductal fluid, and the study of the relevant transport processes will be greatly enhanced by well-differentiated cultures of oviductal epithelium of the kind established here.


Assuntos
Diferenciação Celular , Células Cultivadas , Células Epiteliais/citologia , Haplorrinos , Oviductos/citologia , Animais , Técnicas de Cultura de Células , Polaridade Celular , Separação Celular , Eletrofisiologia , Células Epiteliais/fisiologia , Feminino , Oviductos/fisiologia
5.
Microb Ecol ; 52(4): 619-33, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17072678

RESUMO

Salt marshes are important ecosystems whose plant and microbial communities can alter terrestrially derived pollutants prior to coastal water discharge. However, knowledge regarding relationships between anthropogenic pollutant levels and salt marsh microbial communities is limited, and salt marshes on the West Coast of the United States are rarely examined. In this study, we investigated the relationships between microbial community composition and 24 pollutants (20 metals and 4 organics) in two California salt marshes. Multivariate ordination techniques were used to assess how bacterial community composition, as determined by terminal restriction fragment length polymorphism and phospholipid fatty acid analyses, was related to pollution. Sea urchin embryo toxicity measurements and plant tissue metabolite profiles were considered two other biometrics of pollution. Spatial effects were strongly manifested across marshes and across channel elevations within marshes. Utilizing partial canonical correspondence analysis, an ordination technique new to microbial ecology, we found that several metals were strongly associated with microbial community composition after accounting for spatial effects. The major patterns in plant metabolite profiles were consistent with patterns across microbial community profiles, but sea urchin embryo assays, which are commonly used to evaluate ecological toxicity, had no identifiable relationships with pollution. Whereas salt marshes are generally dynamic and complex habitats, microbial communities in these marshes appear to be relatively sensitive indicators of toxic pollutants.


Assuntos
Ecossistema , Sedimentos Geológicos/microbiologia , Áreas Alagadas , Animais , California , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/embriologia , Ácidos Graxos/análise , Geografia , Análise Multivariada , Fosfolipídeos/química , Plantas/metabolismo , Polimorfismo de Fragmento de Restrição , Ouriços-do-Mar/embriologia , Poluentes do Solo/análise
6.
Eur J Vasc Endovasc Surg ; 32(1): 97-100, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16426871

RESUMO

PURPOSE: To present our technique of pre-arteriotomy guidewire access (PAGA). SUMMARY: Placement of a guidewire across inflow lesions before performing the arteriotomy during combined endovascular/open procedures while treating patients with complex iliofemoral occlusive disease is a crucial maneouvre. We routinely utilize this approach in patients in whom endarterectomy and/or patch angioplasty is planned as the central part of the revascularization procedure, or when we find an unsuspected severely diseased EIA in a patient undergoing leg revascularization.


Assuntos
Angioplastia , Arteriopatias Oclusivas/terapia , Endarterectomia , Isquemia/terapia , Perna (Membro)/irrigação sanguínea , Angioplastia/métodos , Arteriopatias Oclusivas/cirurgia , Terapia Combinada , Artéria Femoral/cirurgia , Humanos , Artéria Ilíaca/cirurgia , Isquemia/cirurgia , Stents
7.
J Membr Biol ; 207(3): 119-29, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16550483

RESUMO

Based on the amino-acid sequence of the macaque epididymal secretory protein, ESP 13.2 (Q9BEE3/AJ236909), it has now been classified as beta-defensin DEFB126. DEFB126 is one of the five beta-defensins with genes that are clustered along chromosome 20pl3, and all five proteins have an extended carboxy terminus that continues beyond the 6-cysteine beta-defensin core region. This 60-amino acid carboxyl tail extension of the DEFB126 molecule is extraordinarily rich in threonine and serine (40%), many of which appear to be likely candidates for having O-glycosylation. DEFB126 has been shown to coat the entire surface of cynomolgus macaque sperm as they move through the corpus/caudal region of the epididymis. It is a major glycocalyx barrier to the external environment and is retained until the completion of capacitation. Sperm exposed to fluorescein-conjugated poly-L-lysine or Alexa488-histone showed a very uniform fluorescent labeling pattern over the entire sperm surface, almost identical to that observed with anti-DEFB126 Ig label. Sperm surface components that were released following treatment with caffeine/cAMP (in vitro capacitation) were blotted and probed with three different lectins which are known to recognize terminal sialic acid residues, and all three recognized the 35 kDa DEFB126 band. Neuraminidase treatment of sperm shifted the molecular weight of DEFB126 from 34-36 kDa to approximately 38-40 kDa and removed or greatly inhibited sialic acid-specific lectin recognition. O-Glycanase treatment alone was ineffective at removal of the oligosaccharides, but prior treatment with neuraminidase was sufficient to enable the O-glycanase treatment to effectively change the apparent molecular weight to 10 kDa, confirming that a major portion of the molecular mass is associated with the carbohydrate portion. Western blots of neuraminidase-treated DEFB126 showed strong recognition with a number of lectins that identify beta-galactose and also lectins that recognize the N-acetylgalactosamine-serine/threonine, the proposed connection site of O-glycosylation. All of the lectins that recognized DEFB126 on Western blots were used to fluorescently probe sperm. The fluorescent patterns that were observed with poly-L-lysine, Alexa488-histone, sialic acid-specific lectins, and galactose-specific lectins showed even distributions over the entire sperm surface and the patterns were identical to sperm labeled with anti-DEFB126 Ig, and all but the antibody did not recognize neuraminidase-treated sperm.


Assuntos
Carboidratos/análise , Carboidratos/química , Proteínas Secretadas pelo Epidídimo/análise , Proteínas Secretadas pelo Epidídimo/química , Glicocálix/metabolismo , Análise de Sequência de Proteína , Espermatozoides/metabolismo , Sequência de Aminoácidos , Animais , Células Cultivadas , Macaca fascicularis , Masculino , Dados de Sequência Molecular , beta-Defensinas
8.
Mol Reprod Dev ; 63(4): 488-99, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12412052

RESUMO

To identify a sperm-surface component that is highly antigenic, we immunized female cynomolgus macaques with glycosylphosphatidylinositol (GPI)-anchored sperm surface proteins that were released following treatment with phosphatidylinositol-specific phospholipase C (PI-PLC). Five different adjuvants were used in combination with the PI-PLC-released proteins, and three of these proteins (24, 48, and 53 kDa) were shown to be potent antigens for immunization of female monkeys. The 53 kDa protein was found to be a surface coating protein and not a GPI-anchored protein. Polyclonal antibodies to the 24 kDa protein and the 48 kDa protein were produced in rabbits. The two antibodies recognized both proteins on Western blots. The same rabbit antibodies recognized 28, 18, and 10 kDa bands on a Western blot of chemically reduced PI-PLC-released proteins, suggesting that the 48 kDa protein is a dimer of the 24 kDa protein, which we refer to as MAK248. Rabbit polyclonal antibodies developed to reduced fragments of the 24 kDa protein showed that the 18 and 10 kDa bands are proteolytic peptide fragments of the 24 kDa protein. Screening of tissues from male macaques showed that MAK248 is expressed only in the epididymis. Microsequencing of two proteolytic fragments of the 18 kDa component showed 100% amino acid homology to a 233 deduced amino acid sequence previously identified in human testes genome. Antibodies to MAK248 recognized a 24 kDa protein released from human sperm exposed to PI-PLC. Antibodies to MAK248 recognized the equatorial segment and posterior head regions of capacitated cynomolgus macaque sperm. Structural analysis suggests that MAK248 is a novel CRISP protein and a member of the CAP (CRISP, Ag 5, PR-1) family of proteins. Based on amino acid sequence homology, it is possible that MAK248 functions as a protease inhibitor.


Assuntos
Glicosilfosfatidilinositóis/metabolismo , Macaca fascicularis/metabolismo , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/metabolismo , Cabeça do Espermatozoide/metabolismo , Sequência de Aminoácidos , Animais , Western Blotting , Humanos , Masculino , Glicoproteínas de Membrana/genética , Dados de Sequência Molecular , Peso Molecular , Fragmentos de Peptídeos/química , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos
9.
Mol Reprod Dev ; 60(4): 542-52, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11746965

RESUMO

The macaque sperm surface protein PH-20 is a hyaluronidase, but it also interacts with hyaluronic acid (HA) to increase internal calcium ( [Ca(2+)](i) ) in the sperm cell. A region of the PH-20 molecule, termed Peptide 2 (aa 205-235), has amino acid charge homology with other HA binding proteins. The Peptide 2 sequence was synthesized and two recombinant PH-20 proteins were developed, one containing the Peptide 2 region (G3, aa 143-510) and one without it (E12, aa 291-510). On Western blots, affinity-purified anti-Peptide 2 IgG recognized the 64 kDa band corresponding to PH-20 in acrosome intact sperm and, under reducing conditions, recognized the whole 67 kDa PH-20 and the endoproteolyzed N-terminal fragment of PH-20. HA conjugated to a photoaffinity substrate specifically bound to sperm surface PH-20. Indirect immunofluorescence demonstrated that Fab fragments of anti-Peptide 2 IgG bound to the head of live sperm. Biotinylated HA was bound by Peptide 2 and by sperm extracts in a microplate binding assay, and this binding was inhibited by Fab fragments of anti-Peptide 2 IgG. Biotinylated HA bound to the G3 protein and this binding was inhibited by anti-Peptide 2 Fab, but HA did not bind to the E12 protein. Fab fragments of anti-Peptide 2 IgG inhibited the increase in [Ca(2+)](i) induced in macaque sperm by HA. Our results suggest that the Peptide 2 region of PH-20 is involved in binding HA, which results in the cell signaling events related to the elevation of [Ca(2+)](i) during sperm penetration of the cumulus.


Assuntos
Sinalização do Cálcio , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/metabolismo , Ácido Hialurônico/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Biotinilação , Cálcio/metabolismo , Moléculas de Adesão Celular/imunologia , Extratos Celulares , Hialuronoglucosaminidase , Immunoblotting , Macaca , Masculino , Dados de Sequência Molecular , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Capacitação Espermática , Espermatozoides/citologia , Espermatozoides/imunologia , Espermatozoides/metabolismo
10.
Matrix Biol ; 20(8): 515-25, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11731269

RESUMO

The ovulated mammalian oocyte is surrounded by the "cumulus ECM", composed of cells embedded in an extracellular matrix that is rich in hyaluronic acid (HA). The cumulus ECM is a viscoelastic gel that sperm must traverse prior to fertilization. Mammalian sperm have a GPI-anchored hyaluronidase which is known as PH-20 and also as SPAM 1. PH-20 is located on the sperm surface, and in the lysosome-derived acrosome, where it is bound to the inner acrosomal membrane. PH-20 appears to be a multifunctional protein; it is a hyaluronidase, a receptor for HA-induced cell signaling, and a receptor for the zona pellucida surrounding the oocyte. The zona pellucida recognition function of PH-20 was discovered first. This function is ascribed to the inner acrosomal membrane PH-20, which appears to differ biochemically from the PH-20 on the sperm surface. Later, when bee venom hyaluronidase was cloned, a marked cDNA sequence homology with PH-20 was recognized, and it is now apparent that PH-20 is the hyaluronidase of mammalian sperm. PH-20 is unique among the hyaluronidases in that it has enzyme activity at both acid and neutral pH, and these activities appear to involve two different domains in the protein. The neutral enzyme activity of plasma membrane PH-20 is responsible for local degradation of the cumulus ECM during sperm penetration. Plasma membrane PH-20 mediates HA-induced sperm signaling via a HA binding domain that is separate from the hyaluronidase domains. This signaling is associated with an increase in intracellular calcium and as a consequence, the responsiveness of sperm to induction of the acrosome reaction by the zona pellucida is increased. There is extensive evidence that GPI-anchored proteins are involved in signal transduction initiated by a diverse group of cell surface receptors. GPI-anchored proteins involved in signaling are often associated with signaling proteins bound to the cytoplasmic leaflet of the plasma membrane, typically Src family, non-receptor protein tyrosine kinases. PH-20 appears to initiate intracellular signaling by aggregating in the plasma membrane, and a 92-kDa protein may be the cell signaling molecule linked to PH-20.


Assuntos
Moléculas de Adesão Celular/metabolismo , Glicosilfosfatidilinositóis/metabolismo , Hialuronoglucosaminidase/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/genética , Matriz Extracelular/metabolismo , Feminino , Humanos , Hialuronoglucosaminidase/química , Hialuronoglucosaminidase/genética , Líquido Intracelular/metabolismo , Masculino , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Transdução de Sinais , Interações Espermatozoide-Óvulo , Espermatozoides/metabolismo
11.
Semin Vasc Surg ; 14(4): 245-54, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11740832

RESUMO

Because of the limited ability to alter the course of acute renal failure, the vascular surgeon's best strategy is prevention of renal dysfunction. Preoperative screening can identify patients at high risk for acute renal failure after aortic reconstruction. Although the mainstay of preventative therapy is maintenance of adequate renal perfusion, other adjunctive measures are available before, during, and after aortic surgery, which may reduce the incidence of acute renal failure.


Assuntos
Injúria Renal Aguda/etiologia , Aorta/cirurgia , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/complicações , Ruptura Aórtica/cirurgia , Procedimentos Cirúrgicos Vasculares , Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/terapia , Humanos , Incidência , Rim/fisiopatologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/terapia , Procedimentos Cirúrgicos Vasculares/efeitos adversos
12.
Ann Vasc Surg ; 15(5): 567-70, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11665443

RESUMO

Percutaneous devices have been developed to close the femoral artery puncture site after catheterization. Because direct compression is not needed, the devices save time for the treating health-care provider, reduce patient discomfort, and obviate the need for post-catheterization bed rest. Reported complications with use of these devices are similar in nature and frequency to those accompanying direct compression. Complications of infection requiring surgical treatment are exceedingly rare with use of these devices. We describe a series of five catheterization site infections occurring among 1807 patients (0.3%) whose femoral artery puncture was closed with a percutaneous suture closure device. All patients required operative intervention and there was one late death. Physicians should be aware of this uncommon but serious complication to expedite evaluation and treatment of patients with suspected infections from these devices.


Assuntos
Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Artéria Femoral/cirurgia , Infecção da Ferida Cirúrgica/etiologia , Idoso , Segurança de Equipamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Dis Aquat Organ ; 46(2): 147-52, 2001 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-11678230

RESUMO

Rickettsiales-like prokaryotes appear to be etiologic agents of a number of newly described diseases of fish and shellfish. 'Candidatus Xenohaliotis californiensis' is a Rickettsiales-like prokaryote responsible for withering syndrome, a fatal disease of wild and farmed Eastern Pacific abalone, Haliotis spp. The bacterium proliferates in gastrointestinal epithelial cells, forming large intracytoplasmic inclusions. We describe a method of rapidly detecting and assessing the intensity of 'Candidatus Xenohaliotis californiensis' infections in abalone gastrointestinal tissue using the nucleic acid-specific fluorochrome Hoechst 33258. In excised tissue pieces dried onto slides, rehydrated in the Hoechst stain and viewed with ultraviolet light, the large bacterial inclusions were strongly fluorescent and could be easily distinguished from smaller host cell nuclei. This provided a rapid, inexpensive alternative to paraffin section microscopy or molecular techniques, allowing detection of the pathogen within minutes of tissue excision. Comparison of the fluorochrome method with conventional histological analysis for the ability to detect inclusions in 109 samples was 90% accurate, with discrepancies due to false negative diagnosis of low-level infections. An alternative nucleic acid-specific fluorochrome, propidium iodide, showed a staining pattern identical to that of Hoechst 33258. These methods should prove useful for the rapid detection of inclusion-forming Rickettsiales-like prokaryotes in tissues from many host species.


Assuntos
Alphaproteobacteria/isolamento & purificação , Moluscos/microbiologia , Animais , Chlamydiaceae/isolamento & purificação , Reações Falso-Negativas , Corantes Fluorescentes , Microscopia Ultravioleta/veterinária , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
J Invest Dermatol ; 117(4): 864-70, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11676824

RESUMO

Expression of the transcription factor AP-2alpha was examined in cultured human epidermal cells. Levels of AP-2alpha mRNA increased substantially after the cultures reached confluence, similar to the expression pattern of the differentiation markers involucrin and keratinocyte transglutaminase. The level of AP-2alpha protein in nuclear extracts declined markedly after confluence, however, along with its ability to form complexes with oligonucleotides containing the AP-2 response element. In contrast, the levels of AP-2alpha protein in cytoplasmic extracts increased dramatically after confluence, but these extracts had low DNA binding activity. Supershift experiments with specific antisera detected only AP-2alpha and not the beta or gamma isoforms. Examination of its localization by confocal microscopy revealed that AP-2alpha was primarily in the nucleus of basal cells and largely cytoplasmic in the most superficial cells. Localization was a dynamic phenomenon in that changing the medium resulted in accumulation of this transcription factor in the nucleus after several hours. Overall, the data indicate that AP-2alpha transcriptional activity is regulated in a differentiation-dependent manner in cultured keratinocytes and that this occurs by relocalization of the protein. Nuclear localization of the AP-2alpha protein in basal cells permits its accessibility to response elements in gene promoters, whereas sequestration in the cytoplasm as the differentiation program progresses curtails its transcriptional activity. This regulatory scheme may provide keratinocytes with the ability to restore AP-2 transcriptional activity rapidly by redistribution to the nucleus after receiving an appropriate growth signal, such as a medium change.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Células Epidérmicas , Epiderme/metabolismo , Fatores de Transcrição/metabolismo , Diferenciação Celular , Núcleo Celular/química , Células Cultivadas , Citoplasma/química , Proteínas de Ligação a DNA/genética , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Microscopia Confocal , Isoformas de Proteínas/genética , Precursores de Proteínas/genética , RNA Mensageiro/metabolismo , Fatores de Tempo , Distribuição Tecidual , Extratos de Tecidos/metabolismo , Fator de Transcrição AP-2 , Fatores de Transcrição/genética , Transglutaminases/genética
15.
Reproduction ; 121(5): 735-43, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11427161

RESUMO

The mammalian sperm hyaluronidase, PH-20, is active in macaque spermatozoa at neutral and acid pH. Antibodies were produced to synthesized peptides representing regions of PH-20 that may be involved in hyaluronidase activity and designated peptide 1 (amino acid sequence 142-172) and peptide 3 (amino acid sequence 277-297). Western blotting of proteins extracted from the surface of acrosome-intact spermatozoa showed that the two peptide-specific, affinity-purified IgGs label a 64 kDa band corresponding to the PH-20 molecule. Western blots of acrosome-reacted spermatozoa showed that, under reducing conditions, the two anti-peptide IgGs label the 44 kDa band only, which represents the N-terminal fragment of PH-20. Anti-peptide 3 IgG also labels the 53 kDa form of PH-20 in extracts of acrosome-reacted spermatozoa. Peptide-specific, affinity-purified Fab fragments from both IgGs were shown by fluorescence microscopy and transmission electron microscopy to label the sperm plasma membrane, fused acrosomal vesicles, acrosomal matrix and inner acrosomal membrane. Fab fragments of anti-peptide 1 IgG, but not anti-peptide 3 IgG, inhibited hyaluronidase activity of PH-20 from the sperm surface and from extracts of acrosome-reacted spermatozoa at pH 7.0. Fab fragments of both anti-peptide IgGs inhibited sperm hyaluronidase activity at pH 5.0. It is concluded that the region of PH-20 encompassed by the amino acid sequence 142-172 is essential for hyaluronidase activity at neutral pH, whereas the region of amino acid sequence 277-297 may be more important at a lower pH. It is likely that these two regions are the acid/base catalyst site and the nucleophilic site, respectively, of PH-20 hyaluronidases.


Assuntos
Moléculas de Adesão Celular/química , Espermatozoides/enzimologia , Reação Acrossômica , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos , Sítios de Ligação , Western Blotting , Moléculas de Adesão Celular/imunologia , Moléculas de Adesão Celular/metabolismo , Membrana Celular/enzimologia , Inibidores Enzimáticos/farmacologia , Hialuronoglucosaminidase , Concentração de Íons de Hidrogênio , Fragmentos Fab das Imunoglobulinas , Imunoglobulina G/farmacologia , Macaca fascicularis , Masculino , Microscopia Eletrônica , Microscopia de Fluorescência , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Proteínas Recombinantes/análise , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Relação Estrutura-Atividade
16.
Am Surg ; 67(2): 131-4, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11243535

RESUMO

Iodine-125 brachytherapy is an effective well-tolerated treatment for localized prostate cancer. Gastrointestinal complications of brachytherapy (minor rectal bleeding or tenesmus) are uncommon. Rectal ulceration or rectourethral fistulas after prostate brachytherapy are rare. We present a case of massive refractory rectal bleeding and rectourethral fistula, a complication of prostate brachytherapy never before reported. As a result of the patient's life-threatening symptoms aggressive surgical therapy was necessary.


Assuntos
Braquiterapia/efeitos adversos , Hemorragia Gastrointestinal/etiologia , Radioisótopos do Iodo/uso terapêutico , Neoplasias da Próstata/radioterapia , Doenças Retais/etiologia , Fístula Retal/etiologia , Doenças Uretrais/etiologia , Fístula Urinária/etiologia , Adenocarcinoma/radioterapia , Idoso , Hemorragia Gastrointestinal/cirurgia , Humanos , Masculino , Doenças Retais/cirurgia , Fístula Retal/cirurgia , Doenças Uretrais/cirurgia , Fístula Urinária/cirurgia
17.
Aquat Toxicol ; 51(2): 225-39, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11064126

RESUMO

The effects of diffusible creosote-derived compounds from weathered creosote-treated pilings on embryonic development in the Pacific herring were investigated. Parameters used to evaluate toxicity included embryonic development, cardiac function, embryo/larval activity (movement of developing embryos), hatching success, and larval morphology at hatch. For acute exposures, embryos were incubated in seawater containing either creosote-treated wood (creosote) or untreated wood (wood control), or seawater alone (control). All embryos adhering directly to creosote-treated wood and 40-50% of embryos not adhering to the creosote-treated wood failed to develop beyond the first few days of incubation. For surviving embryos, a 93% reduction in heart rate, and moderate to marked arrhythmia was observed. Surviving embryos also exhibited both an increase in frequency and an alteration in pattern of embryo/larval movement, with most embryos exhibiting tremors as compared with the vigorous movements of the control embryos. Cardiac function and embryo/larval movements of embryos exposed to untreated wood were not significantly different from controls. The hatching rate of embryos exposed to creosote was 90% lower than control embryos and 72.4% lower than embryos exposed to untreated wood, and the LC(50) for hatching success was 0.05 mg/l. Partial hatching (incomplete hatch) was observed in 15-20% of embryos exposed to creosote. All of the hatched larvae exposed as embryos to creosote exhibited morphological deformities, including scoliosis, pericardial edema and/or ascites. Similar effects were observed in embryos collected from creosoted pilings in San Francisco Bay, with a 72% decrease in hatching success compared with embryos collected from the Bay and severely deformed larvae. To investigate the combined effects of creosote and salinity on hatching success, larval morphology, and cardiac function, embryos were exposed to a sublethal concentration of creosote (0.003 mg/l) at three salinities; sub-optimal (8 parts per thousand (ppt)), optimal (16 ppt), and high salinity (28 ppt). The presence of creosote decreased hatching success at all three salinities, but the effect was greatest at 8 ppt (34% reduction) and the least in 28 ppt (14% reduction). The increased incidence of morphological abnormalities was also smallest at the high salinity (10% compared with 24 and 33% in 8 and 16 ppt). While exposure to creosote resulted in reduced heart rates at all three salinities, no additive effect of creosote and salinity was observed.


Assuntos
Creosoto/toxicidade , Peixes/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade , Animais , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Dose Letal Mediana , Água do Mar/análise , Cloreto de Sódio/análise , Espectrofotometria Ultravioleta , Madeira
18.
J Trauma ; 49(4): 679-86; discussion 686-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11038086

RESUMO

BACKGROUND: Accurate data are needed to evaluate clinical outcomes, therapeutic modalities, and quality of care in trauma. Administrative data, usually used for billing, have been used to evaluate performance and assess therapy in other medical specialties. This study was performed to determine whether administrative databases are accurate in the recording of information about trauma patients with splenic injuries. METHODS: Patients who had blunt splenic injuries were identified using a state trauma registry. The medical records of those patients were reviewed. The data collected by chart review were compared with data in the statewide administrative database of patients who had splenic injuries at the same four Level I and II trauma centers in the same 5-year period. Age, sex, admission date, and hospital were matched to assure comparison of the identical cohort. chi2 analysis was used to compare dichotomous data and Student's t test continuous data. RESULTS: The administrative database identified 641 and the trauma registry identified 529 patients with a diagnosis of splenic injury. A total of 401 patients were found in both databases. Of these, 120 (22.7%) patients were not recorded in the administrative database. Injury Severity Score was underreported by the administrative database (25.74 +/- 14.7 vs. 19.52 +/- 11, p < 0.0001). The administrative database underreported orthopedic, chest, and head injuries (317 vs. 215, 325 vs. 228, and 234 vs. 155, respectively; all p < 0.0001). Use of abdominal computed tomographic scan and diagnostic peritoneal lavage were also underreported (260 vs. 56 and 104 vs.17, both p < 0.0001). The number of operations on the spleen and number of orthopedic procedures were underreported (259 vs. 225, p < 0.014 and 147 vs. 94, p < 0.0001). Complications were markedly underreported by the administrative database (200 vs. 47, p < 0.0001) CONCLUSION: This study shows that administrative data lack accuracy in the recording of associated injuries, injury severity, diagnostics, procedures, and outcomes data in patients with splenic injuries. Whether these data should be used to evaluate treatment modalities or quality of care in trauma is questionable.


Assuntos
Coleta de Dados/métodos , Documentação/métodos , Sistemas de Informação Administrativa/normas , Garantia da Qualidade dos Cuidados de Saúde/estatística & dados numéricos , Centros de Traumatologia/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , North Carolina/epidemiologia , Garantia da Qualidade dos Cuidados de Saúde/métodos , Sistema de Registros , Estudos Retrospectivos , Baço/lesões , Ferimentos não Penetrantes/complicações , Ferimentos não Penetrantes/diagnóstico , Ferimentos não Penetrantes/epidemiologia , Ferimentos não Penetrantes/etiologia , Ferimentos não Penetrantes/terapia
20.
Photochem Photobiol ; 72(3): 308-13, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10989599

RESUMO

The mechanisms and dose-response of UV action on the early development of Macrocystis pyrifera (L.) C. Agardh gametophytes were investigated. Post-release, zoospores undergo germination, germ tube elongation, DNA synthesis, nuclear division and translocation, which were followed for 41 h under laboratory conditions. The spores were exposed to UV radiation before germination (3 h post-release) or before nuclear division (20 h post-release). Biologically effective UV-B doses (BEDDNA300 nm) higher than those used in the experiments are needed for a 50% inhibition in germination (BED50 > 1600 J m-2). Nuclear division/translocation was more sensitive to UV radiation. When the spores were cultured in the dark, UV exposure at both 3 and 20 h post-release resulted in a dose-responsive inhibition of nuclear division/translocation (BED50 64 and 86 J m-2). Culturing in the light indicated recovery in the spores that were irradiated at 3 h post-release (BED50 356 J m-2), whereas no light-dependent recovery occurred within 41 h of culture when irradiated at 20 h post-release (BED50 80 J m-2). The results present a possible mechanism of UV inhibition in early life stages of the giant kelp, suggesting that environmentally relevant UV-B levels can perturb or delay the development and recruitment of the gametophytes by inhibiting nuclear events.


Assuntos
Alga Marinha/efeitos da radiação , Transporte Biológico , Núcleo Celular/metabolismo , Replicação do DNA , Alga Marinha/genética , Alga Marinha/crescimento & desenvolvimento , Raios Ultravioleta
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