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1.
Clin Exp Allergy ; 47(2): 236-244, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27562571

RESUMO

BACKGROUND: Antibiotic use in early life has been linked to disruptions in the microbiome. Such changes can disturb immune system development. Differences have been observed in the microbiota of children with and without allergies, but there have been few studies on antibiotic use and allergic disease. OBJECTIVE: We evaluated associations of early-life antibiotic use with subsequent occurrence of food allergy and other allergies in childhood using electronic health record data. METHODS: We used longitudinal data on 30 060 children up to age 7 years from Geisinger Clinic's electronic health record to conduct a sex- and age-matched case-control study to evaluate the association between antibiotic use and milk allergy, non-milk food allergies, and other allergies. For each outcome, we estimated conditional logistic regression models adjusting for race/ethnicity, history of Medical Assistance, and mode of birth delivery. Models were repeated separately for penicillins, cephalosporins and macrolides. RESULTS: There were 484 milk allergy cases, 598 non-milk food allergy cases and 3652 other allergy cases. Children with three or more antibiotic orders had a greater odds of milk allergy (Odds Ratio; 95% Confidence interval) (1.78; 1.28-2.48), non-milk food allergy (1.65; 1.27-2.14), and other allergies (3.07; 2.72-3.46) compared with children with no antibiotic orders. Associations were strongest at younger ages and differed by antibiotic class. CONCLUSIONS AND CLINICAL RELEVANCE: We observed associations between antibiotic orders and allergic diseases, providing evidence of a potentially modifiable clinical practice associated with paediatric allergic disease. Differences by antibiotic class should be further explored, as this knowledge could inform paediatric treatment decisions.


Assuntos
Antibacterianos/efeitos adversos , Hipersensibilidade Alimentar/epidemiologia , Hipersensibilidade Alimentar/etiologia , Hipersensibilidade/epidemiologia , Hipersensibilidade/etiologia , Antibacterianos/classificação , Estudos de Casos e Controles , Pré-Escolar , Feminino , Hipersensibilidade Alimentar/diagnóstico , Humanos , Hipersensibilidade/diagnóstico , Imunoglobulina E/imunologia , Lactente , Recém-Nascido , Masculino , Hipersensibilidade a Leite/diagnóstico , Hipersensibilidade a Leite/epidemiologia , Hipersensibilidade a Leite/etiologia , Razão de Chances , Fatores de Risco
2.
J Parasitol ; 106(2): 295-307, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32316032

RESUMO

Cyclospora cayetanensis is a coccidian parasite of humans of known and growing importance. However, we are surprisingly naïve as to our understanding of how to diagnose it and how it develops inside the human body. Here we provide details of the developmental stages of C. cayetanensis in the gallbladder of a 33-yr-old male with human immunodeficiency virus. The gallbladder was removed surgically in 2001 because of severe abdominal pain. For the present study, the archived paraffin block of gallbladder was processed for light microscopy and transmission electron microscopy (TEM). Histological sections were examined after staining with hematoxylin and eosin (HE) or using the periodic acid Schiff (PAS) reaction. Immature and mature asexual stages, gamonts, and oocysts were seen in epithelial cells, both in the superficial epithelium and in glands. The merozoites were present singly, in pairs, and 3 or more in a single parasitophorous vacuole in the host cytoplasm. Up to 6 nuclei were seen in immature schizonts without evidence of merozoite formation. Mature schizonts were 7.6 × 5.1 µm and contained up to 10, 3-4 µm long merozoites. Merozoites were 0.6 to 2.0 µm wide, and their shape varied from pear-shaped to slender. Merozoites were generally PAS-positive; however, some were intensely positive, some had only minute granules, while others were PAS-negative. The microgamonts (male) were 6.6 × 5.2 µm and contained fewer than 20 microgametes around a residual body. The microgametes were up to 2 µm long and were flagellated. Macrogamonts (female) contained distinctive eosinophilic wall-forming bodies that varied in size and were less than 1 µm in HE-stained sections. Macrogamonts were 5.8-6.5 × 5.3-6.5 µm. Oocysts in sections were unsporulated and had a diameter of 5.7-7.5 µm. The TEM examination confirmed the histologic findings. The DNA extracted from paraffin sections was confirmed as C. cayetanensis with real-time PCR. The detailed description of the life cycle stages of C. cayetanensis reported here in an immunosuppressed patient could facilitate histopathologic diagnosis of this parasite. We have shown that the parasite's development more closely resembles that of Cystoisospora than Eimeria and that the parasite has multiple nuclei per immature meront indicating schizogony, and we have undermined evidence for a Type II meront.


Assuntos
Cyclospora/crescimento & desenvolvimento , Ciclosporíase/parasitologia , Vesícula Biliar/parasitologia , Infecções por HIV/complicações , Adulto , Cyclospora/genética , Cyclospora/ultraestrutura , Ciclosporíase/imunologia , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Feminino , Vesícula Biliar/patologia , Vesícula Biliar/ultraestrutura , Humanos , Hospedeiro Imunocomprometido , Estágios do Ciclo de Vida , Masculino , Microscopia Eletrônica de Transmissão , Reação em Cadeia da Polimerase em Tempo Real
3.
J Parasitol ; 105(1): 143-145, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30807718

RESUMO

Here, we report confirmation of sarcocysts of Sarcocystis jamaicensis in an experimental intermediate host, IFN-γ gene knockout (KO) mice orally inoculated sporocysts from its natural definitive host, a red-tailed hawk ( Buteo jamaicensis) (RTH). A RTH submitted to the Carolina Raptor Center, Huntersville, North Carolina, was euthanized because it could not be rehabilitated and released. Fully sporulated sporocysts from intestinal scrapings of the RTH were orally fed to 2 laboratory-reared outbred Swiss Webster mice (SW; Mus musculus) and to 2 KO mice. The sporocysts were infective for KO mice but not to SW mice. Both SW mice remained asymptomatic, and neither schizonts nor sarcocysts were found in their tissues when euthanized on day 54 post-inoculation (PI). The KO mice developed neurological signs and were necropsied 38-54 days PI. Schizonts/merozoites were found in both KO mice euthanized and they were confined to the brain. The predominant lesion was meningoencephalitis. Microscopic sarcocysts were found in muscles of both KO mice. When viewed with light microscopy, the sarcocyst wall appeared thin (<1 µm thick) and smooth. Ultrastructural details of sarcocysts are described.


Assuntos
Doenças das Aves/parasitologia , Falcões/parasitologia , Interferon gama/genética , Sarcocystis/fisiologia , Sarcocistose/veterinária , Animais , Doenças das Aves/genética , Doenças das Aves/patologia , Encéfalo/parasitologia , Chlorocebus aethiops , Feminino , Meningoencefalite/parasitologia , Meningoencefalite/patologia , Meningoencefalite/veterinária , Camundongos , Camundongos Knockout , Microscopia Eletrônica de Transmissão/veterinária , North Carolina , Sarcocystis/isolamento & purificação , Sarcocystis/ultraestrutura , Sarcocistose/genética , Sarcocistose/parasitologia , Sarcocistose/patologia , Células Vero
4.
Obes Sci Pract ; 5(3): 220-230, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31275595

RESUMO

OBJECTIVE: Integration of behavioural risk assessment into well-child visits is recommended by clinical guidelines, but its feasibility and impact is unknown. METHODS: A quasi-experimental study evaluated the feasibility and effectiveness of risk assessment on body mass index (BMI) at 1-year follow-up. Children with assessments (intervention) were compared with those who did not complete assessments (non-respondent) and those who received standard care (non-exposed). RESULTS: Analyses included 10,647 children aged 2-9 years (2,724 intervention, 3,324 non-respondent and 4,599 non-exposed). Forty-five per cent of parents completed the assessments. Intervention and non-respondent groups differed in change in BMI z-score at 1 year by -0.05 (confidence interval [CI]: -0.08, -0.02; P = 0.0013); no difference was observed with non-exposed children. The intervention group had a smaller increase in BMI z-score (0.07 ± 0.63) than non-respondent group (0.13 ± 0.63). For children with normal weight at baseline, intervention versus non-respondent groups differed in BMI z-score change by -0.06 (CI: -0.10, -0.02; P = 0.0025). However, children with overweight at baseline in the intervention versus the non-exposed group differed in BMI z-score change (0.07 [CI: 0.02, 0.14]; P = 0.016). When analysed by age, results were similar for 2- to 5-year-olds, but no differences were found for 6- to 9-year-olds. CONCLUSION: Automating risk assessment in paediatric care is feasible and effective in promoting healthy weight among preschool but not older children.

5.
J Parasitol ; 103(5): 547-554, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28617656

RESUMO

Here, we report a new species, Sarcocystis pantherophisi n. sp., with the Eastern rat snake (Pantherophis alleghaniensis) as natural definitive host and the interferon gamma gene knockout (KO) mouse as the experimental intermediate host. Sporocysts (n = 15) from intestinal contents of the snake were 10.8 × 8.9 µm. Sporocysts were orally infective to KO mice but not to laboratory-raised albino outbred house mice (Mus musculus). The interferon gamma KO mice developed schizont-associated neurological signs, and schizonts were cultivated in vitro from the brain. Mature sarcocysts were found in skeletal muscles of KO mice examined 41 days postinoculation (PI). Sarcocysts were slender, up to 70 µm wide and up to 3.5 mm long. By light microscopy, sarcocysts appeared thin-walled (<1 µm) without projections. By transmission electron microscopy, the sarcocyst wall was a variant of "type 1" (type 1i, new designation). The parasitophorous vacuolar membrane (pvm) had approximately 100-nm-wide × 100-nm-long bleb-like evaginations interspersed with 100-nm-wide × 650-nm-long elongated protrusions at irregular distances, and invaginations into the ground substance layer (gs) for a very short distance (6 nm). The gs was smooth, up to 500 nm thick, without tubules, and contained a few vesicles. Longitudinally cut bradyzoites at 54 days PI were banana-shaped, 7.8 × 2.2 µm (n = 5). Molecular characterization using 18S rRNA, 28S rRNA, ITS-1, and cox1 genes indicated a close relationship with other Sarcocystis parasites that have snake-rodent life cycles. The parasite in the present study was molecularly and biologically similar to a previously reported isolate (designated earlier as Sarcocystis sp. ex Pantherophis alleghaniensis) from P. alleghaniensis, and it was structurally different from other Sarcocystis species so far described.


Assuntos
Colubridae/parasitologia , Sarcocystis/fisiologia , Sarcocistose/veterinária , Animais , Bioensaio , Encéfalo/parasitologia , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Conteúdo Gastrointestinal/parasitologia , Interferon gama/genética , Camundongos , Camundongos Knockout , Microscopia Eletrônica de Transmissão/veterinária , Músculo Esquelético/parasitologia , Oocistos , Filogenia , RNA Ribossômico 18S/química , RNA Ribossômico 18S/genética , Sarcocystis/classificação , Sarcocystis/genética , Sarcocystis/isolamento & purificação , Sarcocistose/parasitologia
6.
J Parasitol ; 103(2): 168-169, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28121491

RESUMO

There is considerable confusion concerning the identity of macroscopic Sarcocystis species in camels. Currently 2 species, Sarcocystis cameli and Sarcocystis ippeni, are recognized from 1-humped camel ( Camelus dromedarius ), and sarcocysts of both species are microscopic. Here, we report the identity of macroscopic sarcocysts from the C. dromedarius in Iraq as S. cameli. Five sarcocysts from the muscle of 2 adult camels collected in 1999 and stored in 10% formalin were studied by transmission electron microscopy (TEM). Sarcocysts were 1.5-5.0 mm long and 200-400 µm wide. By TEM, all 5 sarcocysts had thin sarcocyst walls. Ultrastructurally, the sarcocyst wall had "type 9j" villar protrusions similar to those of S. cameli. This is the first confirmation of macroscopic sarcocysts from 1-humped camel as S. cameli.


Assuntos
Camelus/parasitologia , Sarcocystis/isolamento & purificação , Sarcocistose/veterinária , Animais , Esôfago/parasitologia , Iraque , Microscopia Eletrônica de Transmissão/veterinária , Músculos/parasitologia , Sarcocystis/classificação , Sarcocystis/ultraestrutura , Sarcocistose/parasitologia
7.
J Parasitol ; 103(6): 768-777, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28783438

RESUMO

Here we report a new species of Sarcocystis with a barred owl ( Strix varia) as the natural definitive host and interferon gamma gene knockout (KO) mice as an experimental intermediate host. A barred owl submitted to the Carolina Raptor Center, Huntersville, North Carolina, was euthanized because of paralysis. Fully sporulated 12.5 × 9.9 µm sporocysts were found in intestinal scrapings from the owl. Sporocysts from the barred owl were orally fed to 4 laboratory-reared outbred Swiss Webster (SW) ( Mus musculus) and 8 KO mice. All mice remained asymptomatic. Microscopic sarcocysts were found in all 5 KO mice euthanized on day 32, 59, 120, 154, and 206 post-inoculation (PI), not in KO mice euthanized on day 4, 8, and 14 PI. Sarcocysts were not found in any SW mice euthanized on day 72, 120, 206, and 210 PI. Sarcocysts were microscopic, up to 70 µm wide. By light microscopy, the sarcocyst wall < 2 µm thick had undulating, flat to conical, protrusions of varying dimensions. Numerous sarcocysts were seen in the histological sections of tongue and skeletal muscles from the abdomen, limbs, and eye but not in the heart. By transmission electron microscopy, the sarcocyst wall was "type 1j." The ground substance layer (gs) was homogenous, up to 2 µm thick, with very fine granules, and a few vesicles concentrated toward the villar projections. No microtubules were seen in the gs. Longitudinally cut bradyzoites at 206 days PI were 7.8 × 2.2 µm. Based on molecular characterization using 18S rRNA, 28S rRNA, and cox1 genes and morphology of sarcocysts, the parasite in the present study was biologically and structurally different from species so far described, and we therefore propose a new species name, Sarcocystis strixi n. sp.


Assuntos
Doenças das Aves/parasitologia , Interferon gama/genética , Sarcocystis/isolamento & purificação , Sarcocistose/veterinária , Estrigiformes/parasitologia , Animais , Células Cultivadas , Chlorocebus aethiops , DNA de Protozoário/química , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , DNA Ribossômico/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Intestinos/parasitologia , Rim/citologia , Camundongos , Camundongos Knockout , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Sarcocystis/classificação , Sarcocystis/genética , Sarcocystis/crescimento & desenvolvimento , Sarcocistose/parasitologia , Alinhamento de Sequência/veterinária
8.
J Parasitol ; 103(5): 555-564, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28644743

RESUMO

Here, we report a new species of Sarcocystis with red-tailed hawk (RTH, Buteo jamaicensis) as the natural definitive host and IFN-γ gene knockout (KO) mice as an experimental intermediate host in which sarcocysts form in muscle. Two RTHs submitted to the Carolina Raptor Center, Huntersville, North Carolina, were euthanized because they could not be rehabilitated and released. Fully sporulated 12.5 × 9.9-µm sized sporocysts were found in intestinal scrapings of both hawks. Sporocysts were orally fed to laboratory-reared outbred Swiss Webster mice (SW, Mus musculus) and also to KO mice. The sporocysts were infective for KO mice but not for SW mice. All SW mice remained asymptomatic, and neither schizonts nor sarcocysts were found in any SW mice euthanized on days 54, 77, 103 (n = 2) or 137 post-inoculation (PI). The KO mice developed neurological signs and were necropsied between 52 to 68 days PI. Schizonts/merozoites were found in all KO mice euthanized on days 52, 55 (n = 3), 59, 61 (n = 2), 66, and 68 PI and they were confined to the brain. The predominant lesion was meningoencephalitis characterized by perivascular cuffs, granulomas, and necrosis of the neural tissue. The schizonts/merozoites were located in neural tissue and were apparently extravascular. Brain homogenates from infected KO mice were infective to KO mice by subcutaneous inoculation and when seeded on to CV-1 cells. Microscopic sarcocysts were found in skeletal muscles of 5 of 8 KO mice euthanized between 55-61 days PI. Only a few sarcocysts were detected. Sarcocysts were microscopic, up to 3.5 mm long. When viewed with light microscopy, the sarcocyst wall appeared thin (<1 µm thick) and smooth. By transmission electron microscopy, the sarcocyst wall classified as "type 1j" (new designation). Molecular characterization using 18S rRNA, 28S rRNA, ITS-1, and cox1 genes revealed a close relationship with Sarcocystis microti and Sarcocystis glareoli; both species infect birds as definitive hosts. The parasite in the present study was biologically and molecularly different from species so far described in RTHs and we therefore propose a new species name, Sarcocystis jamaicensis n. sp.


Assuntos
Doenças das Aves/parasitologia , Falcões/parasitologia , Sarcocystis/classificação , Sarcocistose/veterinária , Animais , Bioensaio/veterinária , DNA de Protozoário/química , Feminino , Interferon gama/genética , Intestinos/parasitologia , Masculino , Camundongos , Camundongos Knockout , Microscopia Eletrônica de Transmissão/veterinária , Músculo Esquelético/parasitologia , Oocistos/ultraestrutura , Filogenia , Sarcocystis/genética , Sarcocystis/isolamento & purificação , Sarcocistose/parasitologia , Análise de Sequência de DNA/veterinária
9.
Cancer Res ; 49(23): 6795-802, 1989 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-2819719

RESUMO

The structural features of the adult rat hepatocyte (ARH) forms of cell-CAM 105, a Mr 105,000 cell adhesion molecule, were compared using a variety of immunochemical and biochemical techniques with altered forms of more basic pI present on two transplantable hepatocellular carcinomas (THC 1682c and THC AS-30D). Immunoprecipitation analysis with polyclonal (anti-gp 105-2) and monoclonal (MAb) antibodies specific for cell-CAM 105 (MAb 362.50) demonstrated that ARH and THC cell-CAM 105 were indistinguishable in several respects including: (a) binding to wheat germ agglutinin; (b) labeling with NaIO4/NaB3H4; (c) susceptibility to digestion with endoglycosidases (endoglycosidase H and F and peptide N-glycosidase F N-glycanase); (d) rate of turnover on the cell surface; and (e) differential resistance of upper and lower forms to trypsin digestion in the presence or absence of calcium. Digestion with Clostridium perfringens or Vibrio cholerae neuraminidase did not equalize pI but instead decreased the size and increased the pI of both ARH and THC cell-CAM 105. Comparison of two-dimensional tryptic peptide maps, however, revealed five unique peptides in the THC AS-30D map and one peptide in the THC 1682c map, peptides which were only apparent in maps of deglycosylated ARH cell-CAM 105. Based on these results, it was concluded that there were significant differences in the glycosylation of ARH and THC cell-CAM 105. Biosynthetic labeling with 32PO4 and 35SO4 showed that both ARH and THC molecules were phosphorylated but not sulfated. Comparison of 32P-labeled peptides produced by digestion with V-8 protease revealed significant differences in the phosphorylation of the upper and lower forms from ARH and showed that the pattern of phosphorylation on THC cell-CAM 105 most closely resembled ARH upper form. Pulse-chase analysis of ARH cell-CAM 105 further indicated that only a subpopulation of the molecules labeled with [35S]methionine were phosphorylated.


Assuntos
Moléculas de Adesão Celular/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , Fosfatase Alcalina/farmacologia , Animais , Eletroforese em Gel Bidimensional , Glicosídeo Hidrolases/farmacologia , Glicosilação , Peso Molecular , Mapeamento de Peptídeos , Fosforilação , Ratos , Tripsina/farmacologia
10.
Vet Parasitol ; 223: 147-52, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27198793

RESUMO

Paraffin-embedded blocks of brain of a nine months old bull calf that died of neurological signs in 1982 in Germany were restudied. Numerous schizonts and merozoites were found associated with extensive but focal necrosis and severe meningoencephalitis. Developing stages of schizonts as well as free merozoites were identified. The schizonts were primarily in perivascular areas. Ultrastructurally, schizonts were seen both in capillaries and in extravascular space. Merozoites were often concentrated in adventitial layers of capillaries. Schizonts divided by endopolygeny, the nucleus became multi-lobed, and at the terminal stage nuclear lobes were incorporated into budding merozoites. Individual merozoites were seen in neurons, astrocytes, oligodendrocytes, leukocytes, and vascular endothelial cells. Occasionally merozoites were present in the nucleus of mononuclear cells. Individual merozoites were ovoid, 3-5×2-3µm in size, and contained a prominent nucleus, numerous micronemes, a conoid, but no rhoptries. Schizonts and merozoites did not react to polyclonal rabbit Neospora caninum, Toxoplasma gondii, and Sarcocystis neurona antibodies but did react to Sarcocystis cruzi antibodies. Because of morphological characteristics and the type of lesions, the parasite was likely due to an unidentified Sarcocystis species, different from S. cruzi.


Assuntos
Doenças dos Bovinos/parasitologia , Doenças do Sistema Nervoso Central/veterinária , Sarcocistose/veterinária , Animais , Encéfalo/parasitologia , Encéfalo/patologia , Bovinos , Doenças do Sistema Nervoso Central/parasitologia , Doenças do Sistema Nervoso Central/patologia , Masculino , Inclusão em Parafina , Sarcocistose/patologia
11.
Vet Parasitol ; 216: 52-8, 2016 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-26801595

RESUMO

Four Roller pigeons (Columba livia f. dom.) at the Philadelphia Zoo died suddenly. Necropsy examination revealed macroscopic hepatitis. Microscopically, the predominant lesions were in liver, characterized with necrosis and mixed cell inflammatory response. Sarcocystis calchasi-like schizonts and free merozoites were identified in liver. Transmission electron microscopy confirmed that schizonts were in hepatocytes. A few schizonts were in spleen. PCR using S. calchasi-specific primers confirmed the diagnosis. Neither lesions nor protozoa were found in brain and muscles. This is the first report of acute visceral S. calchasi-associated sarcocystosis in naturally infected avian hosts.


Assuntos
Doenças das Aves/parasitologia , Columbidae/parasitologia , Hepatite Animal/parasitologia , Sarcocistose/veterinária , Animais , Animais de Zoológico , Doenças das Aves/mortalidade , Doenças das Aves/patologia , DNA Mitocondrial/química , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Morte Súbita/etiologia , Morte Súbita/veterinária , Complexo IV da Cadeia de Transporte de Elétrons/genética , Hepatite Animal/mortalidade , Hepatócitos/parasitologia , Hepatócitos/ultraestrutura , Imuno-Histoquímica/veterinária , Intestinos/parasitologia , Intestinos/patologia , Fígado/parasitologia , Fígado/patologia , Fígado/ultraestrutura , Microscopia Eletrônica de Transmissão/veterinária , Philadelphia/epidemiologia , Reação em Cadeia da Polimerase/veterinária , RNA Ribossômico 28S/genética , Sarcocystis/genética , Sarcocystis/patogenicidade , Sarcocystis/ultraestrutura , Sarcocistose/mortalidade , Sarcocistose/parasitologia , Baço/parasitologia
12.
J Histochem Cytochem ; 37(10): 1549-52, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2674274

RESUMO

We describe an alternative polyethylene glycol (PEG) embedding procedure which utilizes PEG 200 for dehydration and PEG 600 for infiltration and embedding of perfusion-fixed rat liver. PEG 600 has a melting point of 22 degrees C, enabling infiltration of fixed tissue to be performed at room temperature. Sections (2 microM) cut in a cryostat at -20 degrees C and immobilized in agarose were readily labeled by immunoperoxidase protocols with monoclonal antibodies to hepatocyte membrane antigens. Subsequent examination by light microscopy or by electron microscopy after re-embedding in resin and ultra-thin sectioning showed excellent preservation of morphology, with minimal impairment of antigenicity.


Assuntos
Antígenos de Superfície/análise , Imuno-Histoquímica/métodos , Fígado/imunologia , Polietilenoglicóis , Animais , Anticorpos Monoclonais , Técnicas Imunoenzimáticas , Fígado/ultraestrutura , Masculino , Microscopia Eletrônica , Peso Molecular , Ratos
13.
Clin Pediatr (Phila) ; 35(12): 621-8, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8970754

RESUMO

Surveillance by parental concern has been advocated to assess whether formal child developmental testing is needed. To determine whether alcohol intake or illicit drug use in pregnancy is associated with differences in maternal perception of infant development, mothers with acknowledge alcohol and drug habits during pregnancy (N = 120) were interviewed at 11 months' postpartum, within 1 month before infant testing by use of the Bayley Scales of Infant Development. Women with heavy alcohol intake during pregnancy (> 3.5 oz absolute alcohol per week) were 15-fold more likely to overestimate their infant's mental development (P < 0.05), whereas mothers using illicit drugs were 4-fold more likely to overestimate their infant's physical development (P = 0.02). Given the frequent denial of substance abuse, we suggest that health care providers be cautious in accepting a lack of parental concern about a child's development and rely more heavily on formal testing, particularly in high-risk populations.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Desenvolvimento Infantil/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Transtornos Relacionados ao Uso de Substâncias , Adulto , Feminino , Humanos , Lactente , Masculino , Gravidez , Fumar/efeitos adversos
14.
Hepatology ; 13(1): 47-56, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1988344

RESUMO

Cell-CAM 105 has been identified as a cell adhesion molecule based on the ability of anti-cell-CAM 105 monospecific Fab fragments to inhibit the reaggregation of rat hepatocytes. Because of its adhesive properties, it was expected that cell-CAM 105 would be present on the lateral cell surface where adhesive interactions predominate. Paradoxically, however, immunofluorescence analysis of frozen sections of rat liver using specific monoclonal antibodies indicated that cell-CAM 105 was present exclusively in the bile canalicular domain of the rat hepatocyte where there is no intercellular adhesion. To more precisely define the in situ localization of cell-CAM 105, immunoperoxidase labeling and electron microscopy were used to examine intact and mechanically dissociated liver tissue. Results showed that when accessibility was provided by mechanical dissociation of perfusion fixed liver tissue, cell-CAM 105 could be detected in the pericanalicular region of lateral membranes. In contrast, when hepatocytes were labeled after incubation in vitro under conditions used during adhesion assays to induce reaggregation, cell-CAM 105 rapidly redistributed to all areas of the plasma membrane. Immunofluorescence analysis of primary hepatocyte cultures further revealed that cell-CAM 105 and two other bile canalicular proteins relocalized to discrete domains reminiscent of bile canaliculi, whereas cell-CAM 105 was also present in areas of intercellular contact. Serial section electron microscopy analysis of well-defined, cross-sectional profiles of bile canaliculi suggested the presence of cell-CAM 105-positive membrane folds that extended along the length of the bile canalicular border. In sections from livers in which calcium-dependent adhesive contacts had been disrupted by treatment with ethylenediamine tetraacetate, intact bile canaliculi were found that remained attached only by these border folds. The implications of these results are discussed with regard to a possible role for cell-CAM 105 in bile canalicular formation.


Assuntos
Adenosina Trifosfatases , Moléculas de Adesão Celular/análise , Adesão Celular , Fígado/química , Animais , Anticorpos Monoclonais , Especificidade de Anticorpos , Antígenos CD , Canalículos Biliares/ultraestrutura , Moléculas de Adesão Celular/imunologia , Moléculas de Adesão Celular/fisiologia , Membrana Celular/química , Células Cultivadas , Imunofluorescência , Fígado/ultraestrutura , Proteínas de Membrana/análise , Microscopia Eletrônica , Ratos , Ratos Endogâmicos ACI
15.
Am J Drug Alcohol Abuse ; 24(4): 675-83, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9849777

RESUMO

Alcohol and drug knowledge of inner-city mothers was evaluated following an educational mailing, and the relationship between knowledge and alcohol and illicit drug use during pregnancy was tested. Eighty-four postpartum African-American mothers with known alcohol and drug use during pregnancy received a U.S. Department of Education publication, Growing Up Drug Free: A Parent's Guide to Prevention. Results of a phone-administered quiz from this booklet were compiled, and alcohol and drug use subgroups were compared. The average score was 50%. Half of the women did not know that alcohol is the most commonly used drug in the United States. Few identified alcohol, tobacco, and marijuana as the three drugs most commonly used by children. Lack of teenage substance use experience was perceived to increase the risk of chemical dependency. Drinkers and drug users were fourfold more likely to answer at least six questions correctly (p=.03 each, logistic regression). Parental knowledge of substance use, particularly of alcohol, remains inadequate. We suggest that appropriate parental education tools are still needed for optimal primary prevention of substance use by inner-city children.


Assuntos
Alcoolismo/prevenção & controle , Negro ou Afro-Americano , Conhecimentos, Atitudes e Prática em Saúde , Mães , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , População Urbana , Adolescente , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Alcoolismo/psicologia , Transtornos Relacionados ao Uso de Cocaína/psicologia , Coleta de Dados , Feminino , Humanos , Drogas Ilícitas , Mães/estatística & dados numéricos , Período Pós-Parto , Gravidez , Fumar/psicologia , Transtornos Relacionados ao Uso de Substâncias/psicologia , População Urbana/estatística & dados numéricos
16.
Biochem J ; 262(1): 327-34, 1989 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-2573346

RESUMO

Dipeptidyl peptidase IV (DPP IV) is a cell surface glycoprotein which has been implicated in hepatocyte-extracellular matrix interactions [Hixson, DeLourdes, Ponce, Allison & Walborg (1984) Exp. Cell Res. 152, 402-414; Walborg, Tsuchida, Weeden, Thomas, Barrick, McEntire, Allison & Hixson (1985) Exp. Cell Res. 158, 509-518; Hanski, Huhle & Reutter (1985) Biol. Chem. Hoppe-Seyler 366, 1169-1176]. However, its proteolytic substrate(s) and/or binding protein(s) which mediate this influence have not been conclusively identified. Nitrocellulose binding assays using 125I-labelled DPP IV that was purified to homogeneity from rat hepatocytes revealed a direct interaction of DPP IV with fibronectin. Although fibronectin could mediate an indirect binding of DPP IV to collagen, no evidence was found for a direct binding of DPP IV to native or denatured Type I collagen. Fibronectin appeared to bind DPP IV at a site distinct from its exopeptidase substrate recognition site since protease inhibitors such as competitive peptide substrates and phenylmethanesulphonyl fluoride enhanced binding, possibly as a result of an altered conformation of DPP IV. To determine if fibronectin binding to DPP IV is involved in the interaction of fibronectin with the hepatocyte surface, the effect of various DPP IV inhibitors on 125I-fibronectin binding to isolated hepatocytes in suspension was examined. Kinetic studies revealed that inhibitors of DPP IV which enhanced fibronectin binding in vitro accelerated the initial binding of fibronectin to the cell surface where it was subsequently cross-linked (presumably by tissue transglutaminase) to as yet undefined components. Immunolocalization of fibronectin and DPP IV in normal rat liver sections showed that both proteins were present along the hepatocyte sinusoidal membrane. These observations, coupled with previous results showing that DPP IV is tightly bound to biomatrix isolated from rat liver (Hixson et al., 1984; Walborg et al., 1985), suggest that DPP IV binding to fibronectin may play a role in interactions of hepatocytes with extracellular matrix in vivo and possibly in matrix assembly.


Assuntos
Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Fibronectinas/metabolismo , Fígado/enzimologia , Animais , Sítios de Ligação , Células Cultivadas , Colágeno/metabolismo , Dipeptidil Peptidase 4 , Dipeptidil Peptidases e Tripeptidil Peptidases/antagonistas & inibidores , Matriz Extracelular/metabolismo , Masculino , Ratos , Ratos Endogâmicos ACI
17.
Circulation ; 86(6 Suppl): III117-23, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1424045

RESUMO

Reviewed are various aspects of atherosclerotic plaque stabilization and regression in humans and experimental animals. Plaque regression is a function of the dynamic balance among initiation, progression, stabilization, and removal of plaque constituents. Pseudoregression, the result of the triad thrombolysis, age- or lesion-dependent arterial dilatation, and relaxation of vasospasm, may readily give rise to angiographic misinterpretation. Although lowering of plasma cholesterol and low density lipoprotein-cholesterol has demonstrated significant clinical benefits in a number of clinical trials, the magnitude of angiographic regressive changes is relatively small despite aggressive lipid-lowering regimens. The emerging need for alternative or complementary therapeutic interventions has been emphasized. In particular, they should be targeted to pivotal cellular or molecular mechanisms in initiation, progression, or stabilization. Potentially important therapeutic targets include the use of antioxidants or free radical scavengers such as Probucol or its analogues, butylated hydroxytoluene, tocopherols, and possibly the tocotrienols. Other therapeutic targets include intimal monocyte-macrophage recruitment, macrophage cholesterol acyltransferase inhibition, stimulation of the high density lipoprotein-mediated reverse cholesterol transport system, smooth muscle cell migration to and proliferation in the arterial intima, and intimal connective tissue synthesis. Whether the isoprenylated proteins associated with the cholesterol biosynthetic pathway will give rise to compounds regulating smooth muscle cell growth has yet to be determined. Because of the importance of thrombosis in the pathogenesis and progression of lesions, the need to develop interventional strategies targeted at endothelial cell thromboresistance and thromboregulation must assume a high priority in future research and development. Other areas of therapeutic promise include the calcium channel blockers and angiotensin converting enzyme inhibitors.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Arteriosclerose/fisiopatologia , Animais , Arteriosclerose/sangue , Arteriosclerose/metabolismo , Células Espumosas/patologia , Humanos , Lipoproteínas/sangue , Lipoproteínas/metabolismo , Macrófagos/patologia , Monócitos/patologia , Coelhos
18.
J Pediatr ; 128(4): 573-6, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8618198

RESUMO

In a crossover study of seven term neonates who had neuroimaging studies, chloral hydrate (75 mg/kg administered orally) was more efficacious (p<0.05) but similar with regard to toxic effects than midazolam (0.2 mg/kg administered intravenously). Thus newer drugs are not necessarily better, and monitoring is essential even after a single oral sedative dose.


Assuntos
Hidrato de Cloral , Sedação Consciente , Hipnóticos e Sedativos , Midazolam , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Hidrato de Cloral/farmacologia , Estudos Cross-Over , Humanos , Hipnóticos e Sedativos/farmacologia , Recém-Nascido , Midazolam/farmacologia
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