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1.
Parasitol Res ; 119(8): 2539-2548, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32562068

RESUMO

Strongylida are gastrointestinal nematodes (GIN) of greatest importance in small ruminants throughout the world. Differences in resistance and resilience to GIN among goat breeds were reported. This study aims to investigate the mechanism underlying the breed-associated differences using a cosmopolitan (Alpine, AB) and an autochthonous (Nera di Verzasca, NV) goat breed. At first, fifteen goats from the same herd (NV = 7, AB = 8) at day 0 were infected with infective larvae (L3) of mixed GIN. From the 15th day post-infection (DPI), individual parasite egg excretion (faecal egg counts, FEC) was performed on all goats, once per week, until the 63rd DPI. Afterwards, in goats under field conditions (30 AB and 30 NV reared on the same farm), individual faecal and blood samples were collected; FEC-specific antibody and PCV levels were explored. In goats with experimental GIN infection, mean eggs per gram of faeces (EPG) values were consistently lower in NV goats. In goats with natural GIN infection, EPG and prevalence values showed high variability in both breeds; among individual variables, breed had a significant influence on EPG. Further, PCV and anti-T. circumcincta IgA levels were influenced by the breed. Lower PCV values were also associated with higher strongyle EPG in AB goats, and anti-T. circumcincta IgA levels were influenced by both strongyle EPG and breed, with IgA levels being higher in AB vs. NV goats and positively associated with EPG. Neither EPG nor breed had any influence on IgE levels. Both studies on experimental and natural infection confirmed that goats of NV are more resistant to infection with gastrointestinal nematodes.


Assuntos
Gastroenteropatias/veterinária , Doenças das Cabras/parasitologia , Infecções por Strongylida/veterinária , Animais , Formação de Anticorpos , Fezes/parasitologia , Feminino , Gastroenteropatias/sangue , Gastroenteropatias/parasitologia , Doenças das Cabras/sangue , Cabras/classificação , Cabras/imunologia , Cabras/parasitologia , Masculino , Contagem de Ovos de Parasitas/veterinária , Especificidade da Espécie , Infecções por Strongylida/sangue , Infecções por Strongylida/parasitologia
2.
J Helminthol ; 85(3): 313-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20923583

RESUMO

Thirty-one faecal samples were collected from red deer in the northern area of Varese, in the Italian region of Lombardy, between August and October 2008. The animals had either been hunted or accidently killed. Examination for internal parasites showed a prevalence of 45.2% for Elaphostrongylus cervi larvae and species identification was confirmed by polymerase chain reaction (PCR). Ninety-seven faecal samples were also collected from two goat flocks grazing in the same area between December 2007 and May 2008. These showed a prevalence of 74.7% for lungworms. Furthermore, the central nervous systems from five goats and one sheep from this area with a history of neurologically related lameness were examined. Histopathology confirmed E. cervi cerebro-spinal nematodiasis in five cases out of six. This study demonstrates E. cervi transmission from wild to domestic ruminants when the animals graze in the same area, and the possible occurrence of clinical disease in infected goats and sheep associated with high prevalence in deer.


Assuntos
Helmintíase do Sistema Nervoso Central/veterinária , Líquido Cefalorraquidiano/parasitologia , Cervos/parasitologia , Cabras/parasitologia , Metastrongyloidea/isolamento & purificação , Ovinos/parasitologia , Infecções por Strongylida/veterinária , Animais , Helmintíase do Sistema Nervoso Central/parasitologia , Helmintíase do Sistema Nervoso Central/transmissão , DNA de Helmintos/genética , Fezes/parasitologia , Feminino , Itália , Pulmão/parasitologia , Masculino , Metastrongyloidea/patogenicidade , Reação em Cadeia da Polimerase , Infecções por Strongylida/parasitologia , Infecções por Strongylida/transmissão
3.
Int J Pharm ; 386(1-2): 71-6, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19900522

RESUMO

The in vitro passive diffusion of S-ibuprofen (S-IB) and RS-ibuprofen (RS-IB) through human epidermis was determined to study the effects of drug chirality. S-IB has a lower melting point (T(m)=54 degrees C) than RS-IB (T(m)=77 degrees C) and, therefore, a greater solubility (S-IB: 127+/-1 microg/mL; RS-IB: 81+/-1 microg/mL). Supersaturated plasters were prepared by using a poly(dimethylsiloxane) adhesive and Eugragit RL and propylene glycol as antinucleant agents. The in vitro skin permeation profiles were determined by Franz cells and human epidermis obtained from three different donors. The permeation profiles of S-IB from saturated solutions resulted statistically higher than those of RS-IB (p<0.002). When plasters were used, no differences were noticeable between the enantiomer and racemate (p>0.17). The latter unexpected results could be explained considering that the RS-IB or S-IB in vitro release rate constants, determined using 3% w/w or 6% w/w loaded plasters, were not statistically different, suggesting that the drug diffusivity within the adhesive matrix represented the rate limiting step to the skin absorption.


Assuntos
Anti-Inflamatórios não Esteroides/metabolismo , Epiderme/metabolismo , Ibuprofeno/metabolismo , Absorção Cutânea , Administração Cutânea , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Química Farmacêutica , Difusão , Dimetilpolisiloxanos/química , Formas de Dosagem , Composição de Medicamentos , Excipientes/química , Humanos , Ibuprofeno/administração & dosagem , Ibuprofeno/química , Cinética , Modelos Biológicos , Polímeros/química , Propilenoglicol/química , Solubilidade , Estereoisomerismo , Tecnologia Farmacêutica/métodos , Adesivos Teciduais/química , Temperatura de Transição
4.
J Med Entomol ; 46(6): 1320-6, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19960676

RESUMO

In Chile, the horn fly, Hematobia irritans (L., 1758), is a major pest of grazing cattle and affects livestock production during the summer. Previous studies in Europe and the United States have shown that cattle flies, including H. irritans, are differentially attracted to individual cattle within herds and that volatile semiochemicals are responsible for this phenomenon. This study provides evidence that similar differential attractiveness occurs for the interaction between Chilean Holstein-Friesian cattle herds and local H. irritans populations. Thus, Holstein-Friesian dairy cattle, Bos taurus, which were of similar age and physiological condition, were shown to possess an uneven distribution of H. irritans. Heifers h6904 and h8104 were defined as low-carrier heifers and h5804, h2304 and h1404 as high-carrier heifers. Gas chromatography (GC) and coupled GC-mass spectrometric (GC-MS) analysis of samples collected from heifers revealed the presence of compounds previously reported as semiochemicals for cattle flies, including meta- and para-cresol, methylketones (C8-C11), and 6-methyl-5-hepten-2-one. Other compounds identified included carboxylic acids (butanoic, 3-methylbutanoic, pentanoic, and hexanoic acids), 1-hexanol, and 3-octanone. In Y-tube olfactometer studies, both m- and p-cresol attracted H. irritans at the highest doses tested (10(-6) g), as did the positive control 1-octen-3-ol. Of the other compounds tested, only 2-decanone and 2-undecanone produced a behavioral response, with significantly more flies being recorded in the control arm when the former compound was tested (at 10(-6) and 10(-8) g), and more flies being recorded in the treated arm for the latter compound (at 10(-7) g). This demonstration of behavioral activity with the identified compounds represents a first step for research into the application of semiochemicals in monitoring and control of cattle flies in Chile.


Assuntos
Muscidae/efeitos dos fármacos , Feromônios/farmacologia , Olfato/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Bovinos , Feminino , Masculino , Muscidae/fisiologia , Feromônios/química , Feromônios/isolamento & purificação , Volatilização
5.
J Cell Mol Med ; 13(9B): 3528-40, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19220583

RESUMO

The colon of Ws/Ws mutant rats shows impairment of pacemaker activity and altered inhibitory neurotransmission. The present study set out to find structural correlates to these findings to resolve mechanisms. In the colon of Ws/Ws rats, interstitial cells of Cajal associated with Auerbach's plexus (ICC-AP) were significantly decreased and ICC located at the submuscular plexus and intramuscular ICC were rarely observed based on immunohistochemistry and electron microscopy. Ultrastructural investigations revealed that there was no overall loss of all types of interstitial cells combined. Where loss of ICC was observed, a marked increase in fibroblast-like ICC (FL-ICC) was found at the level of AP. Immunoelectron microscopy proved FL-ICC to be c-Kit(-) but gap junction coupled to each other and to c-Kit(+) ICC; they were associated with enteric nerves and occupied space normally occupied by ICC in the wild-type rat colon, suggesting them to be immature ICC. In addition, a marked increase in immunoreactivity for insulin-like growth factor 1 receptor (Igf1r) occurred, co-localized with CD34 but not with c-Kit. A significantly higher number of Igf1r(+)/CD34(+) cells were found in Ws/Ws compared to wild-type rat colons. These CD34(+)/Igf1r(+) cells in the Ws/Ws colon occupied the same space as FL-ICC. Hence we propose that a subset of immature ICC (FL-ICC) consists of adult progenitor cells. Immunohistochemistry revealed a reduction of neurons positive for neuronal nitric oxide synthase. The functional capabilities of the immature ICC and the regenerative capabilities of the adult progenitor cells need further study. The morphological features described here show that the loss of pacemaker activity is not associated with failure to develop a network of interstitial cells around AP but a failure to develop this network into fully functional pacemaker cells. The reduction in nitrergic innervation associated with the Ws mutation may be the result of a reduction in nitrergic neurons.


Assuntos
Antígenos CD34/biossíntese , Colo/patologia , Fibroblastos/citologia , Células Intersticiais de Cajal/metabolismo , Receptor IGF Tipo 1/metabolismo , Animais , Feminino , Junções Comunicantes , Masculino , Microscopia Imunoeletrônica/métodos , Mutação , Óxido Nítrico Sintase Tipo I/metabolismo , Proteínas Proto-Oncogênicas c-kit/biossíntese , Ratos , Células-Tronco/citologia
6.
Am J Physiol Gastrointest Liver Physiol ; 292(6): G1499-510, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17322067

RESUMO

The aim of this study was to characterize the pacemaker activity and inhibitory neurotransmission in the colon of Ws/Ws mutant rats, which harbor a mutation in the c-kit gene that affects development of interstitial cells of Cajal (ICC). In Ws/Ws rats, the density of KIT-positive cells was markedly reduced. Wild-type, but not Ws/Ws, rats showed low- and high-frequency cyclic depolarization that were associated with highly regular myogenic motor patterns at the same frequencies. In Ws/Ws rats, irregular patterns of action potentials triggered irregular muscle contractions occurring within a bandwidth of 10-20 cycles/min. Spontaneous activity of nitrergic nerves caused sustained inhibition of muscle activity in both wild-type (+/+) and Ws/Ws rats. Electrical field stimulation of enteric nerves, after blockade of cholinergic and adrenergic activity, elicited inhibition of mechanical activity and biphasic inhibitory junction potentials both in wild-type and Ws/Ws rats. Apamin-sensitive, likely purinergic, inhibitory innervation was not affected by loss of ICC. Variable presence of nitrergic innervation likely reflects the presence of direct nitrergic innervation to smooth muscle cells as well as indirect innervation via ICC. In summary, loss of ICC markedly affects pacemaker and motor activities of the rat colon. Inhibitory innervation is largely maintained but nitrergic innervation is reduced possibly related to the loss of ICC-mediated relaxation.


Assuntos
Relógios Biológicos , Colo/inervação , Motilidade Gastrointestinal , Músculo Liso/inervação , Plexo Mientérico/metabolismo , Inibição Neural , Junção Neuromuscular/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Potenciais de Ação , Animais , Apamina/farmacologia , Relógios Biológicos/efeitos dos fármacos , Colo/citologia , Colo/efeitos dos fármacos , Colo/metabolismo , Estimulação Elétrica , Inibidores Enzimáticos/farmacologia , Motilidade Gastrointestinal/efeitos dos fármacos , Técnicas In Vitro , Masculino , Neurônios Motores/metabolismo , Contração Muscular , Relaxamento Muscular , Músculo Liso/citologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Mutação , Plexo Mientérico/citologia , Inibição Neural/efeitos dos fármacos , Junção Neuromuscular/efeitos dos fármacos , Neurônios Nitrérgicos/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Nitroarginina/farmacologia , Proteínas Proto-Oncogênicas c-kit/genética , Ratos , Ratos Mutantes , Bloqueadores dos Canais de Sódio/farmacologia , Tetrodotoxina/farmacologia
7.
Pharmacol Res ; 52(6): 447-56, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16102973

RESUMO

Two pacemakers are involved in the generation of the spontaneous electrical activity in the rat colon. Slow waves, originated near the submuscular plexus, elicit high frequency contractions whereas low frequency contractions are related to cyclic depolarizations, which might be originated near the Auerbach's plexus. Inhibitory junction potentials (IJPs) in the rat colon show a fast component followed by a sustained NO-mediated hyperpolarization. We have utilised mechanical recordings and intracellular electrophysiology to characterize the effects of 4-AP on spontaneous electrical activity and inhibitory neurotransmission in isolated preparations of rat colon. 4-AP reduced the repolarization of smooth muscle cells and caused a transient (for 4-5 min) depolarization (9.7 +/- 3.1 mV; n = 4) and repetitive spikes. The mechanical activity correlated with these electrical changes consisted of a transient increase in tone without cyclic activity followed by long lasting high amplitude cyclic contractions. To avoid smooth muscle cyclic depolarizations, nifedipine 1 microM was added to the perfusion solution. 4-AP 5 mM hyperpolarized (-11.4 +/- 2.1 mV, n = 5) the smooth muscle and induced spontaneous IJPs. This effect was not observed when the tissue was preincubated with TTX 1 microM (n = 7) and L-NNA 1 mM (n = 4). We conclude that 4-AP inhibits repolarization of smooth muscle cells and induces release of NO from nerve endings. This effect might be due to inhibition of K(+) channels both in neurons and smooth muscle cells.


Assuntos
4-Aminopiridina/farmacologia , Colo/efeitos dos fármacos , Junção Neuromuscular/efeitos dos fármacos , Canais de Potássio/efeitos dos fármacos , Animais , Colo/fisiologia , Masculino , Junção Neuromuscular/fisiologia , Nitroarginina/farmacologia , Ratos , Ratos Sprague-Dawley , Transmissão Sináptica/efeitos dos fármacos , Tetrodotoxina/farmacologia
8.
Arch Pediatr ; 12(3): 254-7, 2005 Mar.
Artigo em Francês | MEDLINE | ID: mdl-15734119

RESUMO

UNLABELLED: The deletion of chromosome 22q11.2 is involved in the majority of DiGeorge or velo-cardiofacial syndrome. The phenotypic variability was noted in the "CATCH 22" acronym. This acronym doesn't recapitulate the full spectrum of the symptoms. The diagnosis of this syndrome can be done with the prenatal diagnosis, with fetal pathology or with a child alive. METHODS: Review of 52 cases with the microdeletion 22q11. Six cases were diagnosed during the prenatal period, 12 cases at fetal pathology examination, and 34 cases during infancy. RESULTS: Cardiac malformations were the major indications (75%) to search for the microdeletion. The facial dysmorphy was difficult to diagnose during the antenatal period or in dead foetus, thereby it was not often recognized. The renal anomalies usually present in 35% of cases, were diagnosed in only 6 to 16% of the cases in our study. CONCLUSION: Phenotypic diversity of the DiGeorge syndrome is important. Its knowledge allows to better determine the indications of the research of the microdeletion. 22q11.2.


Assuntos
Síndrome de DiGeorge , Criança , Deleção Cromossômica , Cromossomos Humanos Par 22/genética , Síndrome de DiGeorge/diagnóstico , Síndrome de DiGeorge/genética , Feminino , Morte Fetal/etiologia , Morte Fetal/genética , Humanos , Hibridização in Situ Fluorescente , Recém-Nascido , Masculino , Fenótipo , Gravidez , Diagnóstico Pré-Natal , Pesquisa , Estudos Retrospectivos
9.
Neurogastroenterol Motil ; 17(1): 133-47, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15670273

RESUMO

The aim of this work was to study the patterns of spontaneous motility in the circular and longitudinal muscle strips and to characterize the distribution of c-kit positive interstitial cells of Cajal (ICCs) and nitrergic neurons (nNOS) in the proximal, mid- and distal-colon of Sprague-Dawley rats. We described two types of spontaneous contractions: high frequency (HF) and low frequency (LF) contractions, which were recorded in the presence of tetrodotoxin, suggesting a non-neurogenic origin. Regional differences were found in the motility patterns depending on the muscle layer and on the part of the colon studied. Muscle strips without submuscular plexus (SMP) showed only LF contractions. The density of ICCs was of the same magnitude along the extent of the colon: about 90-120 cells mm(-2) at Auerbach's plexus (AP) and 50-60 cells mm(-2) at the SMP. nNOS positive cells were found at the level of the AP and the major density was found in the mid-colon. Electrical field stimulation abolished LF but did not affect HF contractions. Our results indicate that HF contractions are due to the ICC network found associated with the submuscular plexus (ICC-SMP). The origin of LF contractions is still unknown.


Assuntos
Colo/citologia , Colo/inervação , Motilidade Gastrointestinal/fisiologia , Neurônios/fisiologia , Óxido Nítrico/fisiologia , Animais , Sistema Nervoso Autônomo/citologia , Sistema Nervoso Autônomo/fisiologia , Imuno-Histoquímica , Mucosa Intestinal/inervação , Masculino , Contração Muscular/fisiologia , Músculo Liso Vascular/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Neurotransmissores/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo I , Proteínas Proto-Oncogênicas c-kit/metabolismo , Ratos , Ratos Sprague-Dawley , Tetrodotoxina/farmacologia
11.
Genet Couns ; 15(3): 311-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15517823

RESUMO

This manuscript reports a fetus of 24 weeks gestation, detected on echography to have congenital anomalies: intra-uterine growth retardation, facial dysmorphism, ventricular septal defect with aortic displacement and 8-mm nuchal skinfold thickness. Karyotype was performed. Post termination of pregnancy autopsy showed additionnal internal organ anomalies included: absent gall bladder and thyroid isthmus agenesis. To our knowledge, these anomalies have never been described in trisomic 22 fetuses. This case suggests that chromosome 22 could play a role in thyroid development.


Assuntos
Cromossomos Humanos Par 22/genética , Vesícula Biliar/anormalidades , Glândula Tireoide/anormalidades , Trissomia/genética , Centrômero/genética , Aberrações Cromossômicas , Feminino , Retardo do Crescimento Fetal/genética , Humanos , Hibridização in Situ Fluorescente , Masculino , Gravidez , Resultado da Gravidez
12.
J Gynecol Obstet Biol Reprod (Paris) ; 31(3): 276-82, 2002 May.
Artigo em Francês | MEDLINE | ID: mdl-12016407

RESUMO

Iniencephaly is a rare malformation of the base of the skull. The brain is involved and prognosis is almost invariably lethal. We identified 202 reports in the literature up through 2000. Ultrasound morphology explorations now provide the diagnosis making it possible to propose pregnancy termination. We report four cases of iniencephaly diagnosed between 1992 and 1999.


Assuntos
Defeitos do Tubo Neural/diagnóstico por imagem , Anormalidades Múltiplas/diagnóstico por imagem , Aborto Terapêutico , Adulto , Encéfalo/anormalidades , Encéfalo/patologia , Feminino , Humanos , Recém-Nascido , Gravidez , Estudos Retrospectivos , Crânio/anormalidades , Crânio/patologia , Ultrassonografia Pré-Natal
13.
Am J Physiol Gastrointest Liver Physiol ; 281(1): G255-66, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11408279

RESUMO

Intracellular microelectrodes and organ bath techniques were used to study spontaneous cyclic electrical and mechanical activity in the rat colon. Electron microscopy and immunohistochemical studies showed two major populations of interstitial cells of Cajal (ICC): one associated with Auerbach's plexus (ICC-AP) and one with the submuscular plexus (ICC-SMP). The ICC-SMP network partly adhered to the submucosa when removed and was generally strongly damaged after separation of musculature and submucosa. Similarly, longitudinal muscle removal severely damaged AP. Two electrical and mechanical activity patterns were recorded: pattern A, low-frequency (0.5--1.5 cycles/min), high-amplitude oscillations; and pattern B, high-frequency (13--15 cycles/min), low-amplitude oscillations. Pattern A was recorded in preparations with intact AP but absent in those without intact AP. Pattern B was recorded in preparations with intact SMP but was absent in those lacking SMP. With full-thickness strips, the superimposed patterns A and B were recorded in circular muscle. When longitudinal muscle mechanical activity was recorded, only pattern A was present. We conclude that two pacemakers regulate rat colonic cyclic activity: the ICC-SMP network (responsible for cyclic slow waves and small-amplitude contractions) and the ICC-AP network (which may drive the cyclic depolarizations responsible for high-amplitude contractions). This is the first report showing consistent slow wave activity in the rodent colon.


Assuntos
Relógios Biológicos/fisiologia , Colo/inervação , Colo/fisiologia , Plexo Mientérico/fisiologia , Plexo Submucoso/fisiologia , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Colo/ultraestrutura , Eletrofisiologia , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Microscopia Eletrônica , Contração Muscular/fisiologia , Músculo Liso/inervação , Músculo Liso/fisiologia , Músculo Liso/ultraestrutura , Plexo Mientérico/química , Nifedipino/farmacologia , Peristaltismo/fisiologia , Proteínas Proto-Oncogênicas c-kit/análise , Ratos , Ratos Sprague-Dawley , Plexo Submucoso/química , Tetrodotoxina/farmacologia
14.
Ultrasound Obstet Gynecol ; 17(3): 209-16, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11309169

RESUMO

OBJECTIVES: To evaluate the efficacy of and risk associated with chorionic villus sampling for genetic investigations in multiple pregnancies, and to evaluate the accuracy of the ultrasonographic detection of chorionicity during the first trimester. PATIENTS AND METHODS: A total of 198 sets of twins and nine sets of triplets from 10 087 consecutive first-trimester pregnancies undergoing chorionic villus sampling were considered. Gestational age ranged from 7 to 12.6 weeks. Assessment and confirmation of chorionicity was based on a multiplicity of features. Dichorionicity was established in 169 sets of twins (85.3%) and trichorionicity in all triplet cases, while 29 twins were considered monochorionic. Chorionic villus sampling was performed transabdominally in all but one case, and identification of the placental insertion of the umbilical cord was the main benchmark for sampling. Sampling risks were evaluated by comparing clinical outcome with that of a control population of 63 dichorionic twin pregnancies which underwent no invasive procedure. RESULTS: Determination of the presence or absence of the lambda sign led to a correct assignment of chorionicity in all cases, while the presence of a membrane thickness of 2 mm or more reflected a 100% specificity with a 22% false negative rate. Sampling was successfully performed in all cases and in only four cases (1.0%) were two needle insertions needed. At follow-up no evidence of incorrect sampling was reported. Karyotyping was provided to all patients, and in 94.1% of cases both short and long-term culture methods were carried out. No difference in fetal and perinatal losses between the study and control populations was found, but a higher rate of deliveries before 37 weeks and of low birth weight babies was noted amongst controls. CONCLUSIONS: Chorionicity in twin pregnancy can be determined with certainty between 7 and 12 weeks of gestation; in cases of confluent placentas reliability is provided by determining the presence or absence of the lambda sign. This study indicates that first-trimester transabdominal chorionic villus sampling is a highly efficient, reliable, and relatively safe approach for genetic diagnosis in twin pregnancies. Although a precise evaluation of the relative risks of chorionic villus sampling and mid-trimester amniocentesis in twins must await randomized control studies, the advantages of a first-trimester diagnosis to enable early decision-making about selective fetal reduction are obvious.


Assuntos
Amostra da Vilosidade Coriônica , Gravidez Múltipla , Peso ao Nascer , Amostra da Vilosidade Coriônica/métodos , Feminino , Humanos , Masculino , Gravidez , Resultado da Gravidez , Redução de Gravidez Multifetal , Primeiro Trimestre da Gravidez , Trigêmeos , Gêmeos , Ultrassonografia Pré-Natal
15.
Biopolymers ; 58(1): 33-45, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11072227

RESUMO

This work describes the application of (1)H magic angle spinning (MAS) nmr to the study of hydrated 1Dx5 wheat high-M(r) subunit. 1Dx5 is a water-insoluble 88 kDa protein, associated with good baking performance, and whose structure in the solid and low-hydration states is not known. High-resolution MAS (HR-MAS) results in a threefold resolution improvement of the (1)H spectra of the hydrated wheat protein, compared to standard MAS. The spectral resolution achieved enables, for the first time, two-dimensional nmr methods to be employed for the study of hydrated 1Dx5 and the assignment of the spectrum to be carried out on the basis of total correlated spectroscopy and (13)C/(1)H correlation experiments. Considerable shifts are observed for some resonances, relative to the chemical shifts of amino acids in solution, indicating that specific interactions occur in the hydrated protein network. Two main environments are identified for glutamine residues, Q(1) and Q(2), and these were characterized in terms of possible conformation and relative dynamics, with the basis of comparison between the single 90 degrees spectrum and the Carr-Purcel-Heiboom-Gill (CPMG) spectrum. The Q(1) residues are proposed to be situated in protein segments that adopt the beta-sheet conformation and that remain relatively hindered, possibly by hydrogen bonds involving the glutamine amide groups. On the other hand, Q(2) residues are proposed to be situated in a more mobile environment, adopting a looser conformation, possibly a beta-turn conformation. Based on the proximity of the Q(2) residues with glycine residues, as viewed by the nuclear Overhauser effect spectroscopy experiment, it is proposed that the protein segments that form the more mobile (or loop) sections of the network are rich in both glutamine and glycine residues.


Assuntos
Glutens/análogos & derivados , Glutens/química , Ressonância Magnética Nuclear Biomolecular/métodos , Conformação Proteica , Subunidades Proteicas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Triticum
16.
Prenat Diagn ; 18(9): 893-900, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9793970

RESUMO

To evaluate the potential utility of free beta (hCG) and beta-core (hCG) in a prenatal screening protocol for Down syndrome we analysed these markers in dried maternal urine specimens from 163 control, 13 Down syndrome and 5 trisomy 18 pregnancies from 8 to 25 weeks' gestation. All results are reported after normalization for urinary creatinine determined by modified Jaffe reagent assay. The correlation of urinary free beta (hCG) and urinary beta-core (hCG) was 0.61 in controls and 0.93 in Down syndrome. Median MoM values in Down syndrome were 2.42 for urinary free beta (hCG) and 2.40 for beta-core (hCG). In trisomy 18 the Median MoM was 0.35 and 0.34 for free beta (hCG) and beta-core (hCG), respectively. The degree of elevation observed in DS cases with urinary free beta (hCG) is consistent with previous reports. Studies of beta-core (hCG) in Down syndrome have yielded discrepant results. In this study, beta-core (hCG) in Down syndrome is lower than values observed in early reports but consistent with more recent reports.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/urina , Aberrações Cromossômicas , Síndrome de Down/diagnóstico , Diagnóstico Pré-Natal/métodos , Cromossomos Humanos Par 18 , Reações Falso-Positivas , Feminino , Idade Gestacional , Humanos , Papel , Gravidez , Valores de Referência , Trissomia
17.
Solid State Nucl Magn Reson ; 11(3-4): 203-9, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9694388

RESUMO

Proton spectra of solids are usually broadened by strong proton homonuclear dipolar interactions. However, substantial line narrowing may be achieved by Magic Angle Spinning (MAS) in systems of low proton density or in systems in which rapid molecular motions occur. In such conditions, T1(H) measurements are often used to characterise the dynamics of each resolved proton site. We show that T1(H) values measured for solid organic compounds with high proton abundance, such as adamantane and glycine, may be strongly dependent on the spinning rate employed, so that care is required when values are compared. The effects of molecular motion and proton density on T1(H) and its dependence on spinning rate were investigated. We found that an increase in molecular motion leads to an increase of T1(H) at higher spinning rates. The opposite is found for systems with low proton densities which show relatively lower T1(H), at higher spinning rates. A possible interpretation is suggested in terms of the reduced spin diffusion efficiency at higher spinning rates.


Assuntos
Adamantano/química , Glicina/química , Espectroscopia de Ressonância Magnética/métodos , Humanos , Prótons
18.
Vaccine ; 16(6): 608-12, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9569472

RESUMO

An expression genomic library of Trypanosoma cruzi (T. cruzi) constructed using pcDNA3 plasmid was used for the immunisation (25 micrograms) of Balb/c mice. Expression of T. cruzi antigens in the muscle of inoculated mice was detected by indirect immunofluorescence 7 days after immunisation. Specific IgG antibodies were significatively increased (P < 0.05) in animals that were reimmunized with 50 micrograms of the genomic library. An antigen specific lymphoproliferative response was detected in one animal of the group inoculated with one dose of the library.


Assuntos
DNA de Protozoário/imunologia , Genoma de Protozoário , Vacinas Protozoárias/farmacologia , Trypanosoma cruzi/genética , Trypanosoma cruzi/imunologia , Vacinas de DNA/farmacologia , Animais , Formação de Anticorpos/imunologia , Especificidade de Anticorpos , DNA de Protozoário/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Imunidade Celular/imunologia , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Vacinas Protozoárias/genética , Vacinas Protozoárias/imunologia , Vacinas de DNA/genética , Vacinas de DNA/imunologia
19.
Prenat Diagn ; 18(3): 255-66, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9556042

RESUMO

Chorionic villus sampling (CVS) was performed in 10,000 consecutive singleton pregnancies by a single principal operator, working in two institutions. The procedure was performed between 8 and 32 gestational weeks: transabdominal (TA) sampling was carried out in 8479 cases and transcervical (TC) in 1521. Patients were referred for chromosomal risk in 89.1 per cent of cases, Mendelian disorders in 10.5 per cent, and DNA investigations for paternity or infectious agents in 0.4 per cent of cases. The sampling success rate for both TA and TC techniques by the second insertion was 99.8 and 99.2 per cent, respectively. TA sampling succeeded in a higher number of cases at the first insertion (98 per cent vs. 86.8 per cent) and was associated with smaller samples (< 10 mg) in fewer cases (3.2 per cent vs. 4.9 per cent). Cytogenetic analysis was highly successful (99.4 per cent) and accurate; however, in one case a de novo structural rearrangement of chromosome I was not recognized. Mosaicism or rare trisomies were reported in 1.30 per cent of cases. Five diagnostic errors in DNA investigation (0.51 per cent) ended with the birth of affected fetuses. Fetal loss through 28 weeks' gestation in the pregnancies intended to continue was 2.58 per cent; the rate increased with maternal age (1.22 per cent at less than 30 years to 3.8 per cent at 40 years or more), while gestational age affected the abortion rate only at 8 weeks (odds ratio=2.22, P<0.05). Rates of premature delivery, low birth weight, and perinatal mortality did not differ from the Italian standards. By comparison with the Italian Birth Defects Registry data, no differences were found for the major malformations, including transverse limb reduction defects (TLRDs) (4.34 vs. 3.28 x 10,000). Total malformations and TLRDs did not show any pattern relation to either maternal age or gestational age.


Assuntos
Amostra da Vilosidade Coriônica/estatística & dados numéricos , Doenças Fetais/epidemiologia , Erros Inatos do Metabolismo/epidemiologia , Adulto , Feminino , Idade Gestacional , Humanos , Incidência , Itália/epidemiologia , Cariotipagem , Gravidez , Resultado da Gravidez
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