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1.
Ultrasound Obstet Gynecol ; 58(5): 716-721, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33533520

RESUMO

OBJECTIVES: Placental expression of neuropilin-1 (NRP1), a proangiogenic member of the vascular endothelial growth factor receptor family involved in sprouting angiogenesis, was recently discovered to be downregulated in pregnancies with fetal growth restriction (FGR) and abnormal umbilical artery (UA) Doppler. Soluble NRP1 (sNRP1) is an antagonist to NRP1; however, little is known about its role in normal and FGR pregnancies. This study tested the hypotheses that, first, sNRP1 would be detectable in maternal circulation and, second, its concentration would be upregulated in FGR pregnancies compared to those with normal fetal growth and this would correlate with the severity of the disease as assessed by UA Doppler. METHODS: This was a prospective case-control pilot study of 40 singleton pregnancies (20 FGR cases and 20 uncomplicated controls) between 24 + 0 and 40 + 0 weeks' gestation followed in an academic perinatal center from January 2015 to May 2017. FGR was defined as an ultrasound-estimated fetal weight < 10th percentile for gestational age. The control group was matched to the FGR group for maternal age and gestational age at assessment. Fetal ultrasound biometry and UA Doppler were performed using standard protocols. Maternal plasma sNRP1 measurements were performed using a commercially available ELISA. RESULTS: Contrary to the study hypothesis, maternal plasma sNRP1 levels were significantly decreased in FGR pregnancies as compared to those with normal fetal growth (137.4 ± 44.8 pg/mL vs 166.7 ± 36.9 pg/mL; P = 0.03). However, there was no significant difference in sNRP1 concentration between the control group and FGR pregnancies that had normal UA Doppler. Plasma sNRP1 was downregulated in FGR pregnancies with elevated UA systolic/diastolic ratio (P = 0.023) and those with UA absent or reversed end-diastolic flow (P = 0.005) in comparison to FGR pregnancies with normal UA Doppler. This suggests that biometrically small fetuses without hemodynamic compromise are small-for-gestational age rather than FGR. CONCLUSIONS: This study demonstrated a significant decrease in maternal plasma sNRP1 concentration in growth-restricted pregnancies with fetoplacental circulatory compromise. These findings suggest a possible role of sNRP1 in modulating fetal growth and its potential as a biomarker for FGR. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Retardo do Crescimento Fetal/sangue , Neuropilina-1/sangue , Circulação Placentária , Ultrassonografia Doppler , Ultrassonografia Pré-Natal , Artérias Umbilicais/anormalidades , Adulto , Biometria , Estudos de Casos e Controles , Regulação para Baixo , Feminino , Retardo do Crescimento Fetal/diagnóstico por imagem , Peso Fetal , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Projetos Piloto , Placenta/metabolismo , Gravidez , Estudos Prospectivos , Índice de Gravidade de Doença , Artérias Umbilicais/diagnóstico por imagem , Artérias Umbilicais/embriologia
2.
BJOG ; 121(11): 1395-402, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24506582

RESUMO

OBJECTIVE: To compare composite maternal and neonatal morbidities (CMM, CNM) among nulliparous women with primary indications for caesarean section (CS) as acute clinical emergency (group I; ACE), non-reassuring fetal heart rate (group II) and arrest disorder (group III). DESIGN: A multicentre prospective study. SETTING: Nineteen academic centres in the USA, with deliveries in 1999-2002. POPULATION: Nulliparous women (n = 9829) that had CS. METHODS: Nulliparous women undergoing CS for three categories of indications were compared using logistic regression model, adjusted for five variables. MAIN OUTCOME MEASURES: CMM was defined as the presence of any of the following: intrapartum or postpartum transfusion, uterine rupture, hysterectomy, cystotomy, ureteral or bowel injury or death; CNM was defined as the presence of any of the following: umbilical arterial pH <7.00, neonatal seizure, cardiac, hepatic, renal dysfunction, hypoxic ischaemic encephalopathy or neonatal death. RESULTS: The primary reasons for CS were ACE in 1% (group I, n = 114) non-reassuring FHR in 29% (group II; n = 2822) and failed induction/dystocia in the remaining 70% (group III; n = 6893). The overall risks of CMM and CNM were 2.5% (95% confidence intervals, CI, 2.2-2.8%) and 1.9% (95% CI 1.7-2.2), respectively. The risk of CMM was higher in group I than in group II (RR 4.1, 95% CI 3.1, 5.3), and group III (RR 3.2, 95% CI 2.7, 3.7). The risk of CNM was also higher in group I than in group II (RR 2.8, 95% CI 2.3, 3.4) and group III (RR 14.1, 95% CI 10.7, 18.7). CONCLUSIONS: Nulliparous women who have acute clinically emergent caesarean sections are at the highest risks of both composite maternal and neonatal morbidity and mortality.


Assuntos
Cesárea , Medicina de Emergência , Paridade , Adulto , Cesárea/mortalidade , Cesárea/estatística & dados numéricos , Cistotomia/efeitos adversos , Cistotomia/mortalidade , Feminino , Cardiopatias/epidemiologia , Humanos , Hipóxia-Isquemia Encefálica/epidemiologia , Histerectomia/efeitos adversos , Histerectomia/mortalidade , Recém-Nascido , Enteropatias/epidemiologia , Nefropatias/epidemiologia , Hepatopatias/epidemiologia , Masculino , Morbidade , Gravidez , Estudos Prospectivos , Fatores de Risco , Convulsões/epidemiologia , Artérias Umbilicais/patologia , Estados Unidos/epidemiologia , Doenças Uterinas/mortalidade
3.
Protoplasma ; 245(1-4): 133-41, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20467880

RESUMO

Abiotic stresses, especially salinity and drought, are major limiting factors for plant growth and crop productivity. In an attempt to develop salt and drought tolerant tomato, a DNA cassette containing tobacco osmotin gene driven by a cauliflower mosaic virus 35S promoter was transferred to tomato (Solanum lycopersicum) via Agrobacterium-mediated transformation. Putative T0 transgenic plants were screened by PCR analysis. The selected transformants were evaluated for salt and drought stress tolerance by physiological analysis at T1 and T2 generations. Integration of the osmotin gene in transgenic T1 plants was verified by Southern blot hybridization. Transgenic expression of the osmotin gene was verified by RT-PCR and northern blotting in T1 plants. T1 progenies from both transformed and untransformed plants were tested for salt and drought tolerance by subjecting them to different levels of NaCl stress and by withholding water supply, respectively. Results from different physiological tests demonstrated enhanced tolerance to salt and drought stresses in transgenic plants harboring the osmotin gene as compared to the wild-type plants. The transgenic lines showed significantly higher relative water content, chlorophyll content, proline content, and leaf expansion than the wild-type plants under stress conditions. The present investigation clearly shows that overexpression of osmotin gene enhances salt and drought stress tolerance in transgenic tomato plants.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Solanum lycopersicum , Estresse Fisiológico , Germinação , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/genética , Solanum lycopersicum/fisiologia , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Tolerância ao Sal/fisiologia , Cloreto de Sódio/farmacologia
5.
Plant Cell Rep ; 25(2): 81-4, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16331459

RESUMO

Xanthan gum, a microbial desiccation-resistant polysaccharide prepared commercially by aerobic submerged fermentation from Xanthomonas campestris, has been successfully used as a solidifying agent for plant tissue culture media. Its suitability as a substitute to agar was demonstrated for in vitro seed germination, caulogenesis and rhizogenesis of Albizzia lebbeck, androgenesis in anther cultures of Datura innoxia, and somatic embryogenesis in callus cultures of Calliandra tweedii. Culture media used for eliciting these morphogenic responses were gelled with either 1% xanthan gum or 0.9% agar. Xanthan gum, like agar, supported all these responses.


Assuntos
Ágar , Meios de Cultura/química , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/economia , Técnicas de Cultura de Tecidos , Ágar/química , Ágar/economia , Albizzia/crescimento & desenvolvimento , Datura/crescimento & desenvolvimento , Fabaceae/crescimento & desenvolvimento , Germinação/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Sementes/metabolismo
6.
Lett Appl Microbiol ; 41(4): 345-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16162142

RESUMO

AIMS: To determine the possibility of using guar gum, a colloidal polysaccharide, as a cheap alternative to agar for gelling microbial culture media. METHODS AND RESULTS: As illustrative examples, 12 fungi and 11 bacteria were cultured on media solidified with either guar gum or agar. All fungi and bacteria exhibited normal growth and differentiation on the media gelled with guar gum. Microscopic examination of the fungi and bacteria grown on agar or guar gum gelled media did not reveal any structural differences. However, growth of most of the fungi was better on guar gum media than agar, and correspondingly, sporulation was also more advanced on the former. Bacterial enumeration studies carried out for Serratia sp. and Pseudomonas sp. by serial dilution and pour-plate method yielded similar counts on both agar and guar gum. Likewise, a selective medium, succinate medium used for growth of Pseudomonas sp. did not support growth of Bacillus sp. when inoculated along with Pseudomonas on both agar or guar gum supplemented medium. CONCLUSIONS: Guar gum, a galactomannan, which is 50 times cheaper than Difco-bacto agar, can be used as a gelling agent in place of agar in microbial culture media. SIGNIFICANCE AND IMPACT OF THE STUDY: As the media gelled with guar gum do not melt at temperature as high as 70 degrees C, these can be used for isolation and maintenance of thermophiles.


Assuntos
Bactérias/crescimento & desenvolvimento , Meios de Cultura , Fungos/crescimento & desenvolvimento , Galactanos , Mananas , Ágar , Técnicas Microbiológicas , Gomas Vegetais
7.
Plant Cell Rep ; 19(5): 519-524, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30754893

RESUMO

The epicotyl segments bearing scaly leave(s), excised from in vitro grown seedlings of Syzygium cuminii, produced multiple shoots when cultivated on Murashige and Skoog's (MS, 1962) medium supplemented with different concentrations of BA (0-2 mg l-1). The optimum response was recorded on the medium containing 1 mg l-1 BA. An average of 8.6 shoots per explant were produced 60 days after inoculation, following transfer to fresh medium after 30 days. The shoots were excised, and the residual explants were transferred to fresh medium, where they again developed shoots. Up to five such passages resulted in the production of shoots from the repeatedly subcultured original explants. However, during the fifth passage, organogenic response was negligible and the explants turned brown thereafter. Following repeated harvesting of shoots and subculture of the residual explants, an average of 29 shoots per explant was obtained. The in vitro developed shoots produced roots when transferred to Knop's medium supplemented with 2% sucrose and 1 mg l-1 IAA. The developed plantlets were planted in soil and transferred to fields after an acclimatization period of 7-8 months. These plants have been thriving well for more than 3 years. The nodal explants excised from in vitro developed shoots and plants also exhibited a similar response when cultured on MS+1 mg l-1 BA. Thus, a protocol has been developed to raise plants of S. cuminii at any time of the year.

8.
Plant Cell Rep ; 17(4): 318-322, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30736614

RESUMO

`Isubgol', the mucilaginous husk derived from the seeds of Plantago ovata, was successfully used as a gelling agent in tissue culture media for in vitro seed germination, shoot formation and rooting in Syzygium cuminii and anther culture in Datura innoxia. For seed germination, Knop's basal medium supplemented with 1% sucrose was employed, whereas for the development of shoots the epicotyl segments excised from in vitro-developed seedlings were cultured on MS basal medium supplemented with 4% sucrose and 1 mg/l 6-benzyladenine. Shoots that developed from the epicotyl segments were rooted on Knop's medium enriched with 2% sucrose and 1 mg/l indole-3-acetic acid. The anthers of D. innoxia excised at the late uninucleate to early binucleate stages of microspore development were cultured on Nitsch's basal medium containing 2% sucrose. Media were either gelled with 0.9% agar or 3% `Isubgol'. The response on media gelled with `Isubgol' in each of the cases was similar to that on media solidified with agar.

9.
Int J Cancer ; 51(2): 302-9, 1992 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-1568796

RESUMO

The antitumor activity of epirubicin (EPI) entrapped in long circulating "Stealth" liposomes containing a polyethylene glycol-derivatized phospholipid (S-EPI) was compared to epirubicin encapsulated in a conventional liposome formulation (L-EPI) and free epirubicin (F-EPI) against mouse colon 26 tumor in vivo. Pharmacokinetics of S-EPI and F-EPI were also compared in rats. F-EPI was distributed to tissues within minutes of injection. In contrast, when administered in the S-EPI formulation, the distribution half-life of the drug was over 22 hr. S-EPI also exhibited a reduced clearance compared to F-EPI, from 111 to less than 1.0 ml/hr. S-EPI inhibited tumor growth more effectively than F-EPI or L-EPI by causing tumors to regress and increasing survival of mice. There were 9/10 (S-EPI) compared to 0/10 (F-EPI) 120-day survivors when treatment was started 3 days after tumor implant. When treatment was delayed for 10 days, tumors, which had reached approx. 0.1-0.3 cm3 in volume, regressed in 8/10 animals receiving S-EPI, whereas in all animals treated with F-EPI the tumors progressed. L-EPI was no more effective therapeutically than F-EPI in this model. The maximum tolerated dose of S-EPI was higher than that of F-EPI. The enhanced therapeutic efficacy of S-EPI is probably related to the extended circulation time of the formulation and its accumulation in tumors.


Assuntos
Neoplasias do Colo/metabolismo , Epirubicina/farmacocinética , Animais , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Portadores de Fármacos , Composição de Medicamentos , Resistência a Medicamentos , Epirubicina/uso terapêutico , Feminino , Lipossomos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Ratos Endogâmicos
10.
Antimicrob Agents Chemother ; 36(2): 299-307, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1605595

RESUMO

The safety, pharmacokinetics, and distribution in tissue of an amphotericin B (AmB)-cholesteryl sulfate colloidal dispersion (ABCD) were compared with those of micellar amphotericin B-deoxycholate (m-AmB). Dogs received 14 daily injections of ABCD (0.6 to 10 mg/kg of body weight per day) or m-AmB (0.6 mg/kg/day). Safety was evaluated by monitoring body weight, hematology, clinical chemistry, and urinalysis during the study and by microscopic examination of tissues at the time of necropsy (day 16). AmB concentrations in plasma were measured in some groups on days 1, 7, and 14 and in necropsy tissue samples. ABCD produced a spectrum of toxic effects in the kidneys, gut, and liver similar to those of m-AmB, but ABCD was eightfold safer than m-AmB. The highest tolerated dose of ABCD (5.0 mg/kg/day) produced effects similar to those of m-AmB (0.6 mg/kg/day). ABCD produced lower concentrations in plasma than an equal dose of m-AmB did. Clearances on days 7 and 14 were higher for ABCD (304 and 295 ml/h.kg) than they were for m-AmB (67 and 53 ml/h.kg). Concentrations in plasma reached steady state after ABCD administration, but they increased after repeated dosing with m-AmB. Diurnal fluctuations in AmB concentrations in plasma were observed 4 to 8 h after the time of dosing. ABCD resulted in lower AmB concentrations in tissue than m-AmB did, except in the reticuloendothelial system. Up to 90% of AmB administered as ABCD was recovered from the liver and spleen on day 16. Reduced drug levels in the kidneys and gut correlated with reduced indications of toxicity in these organs after ABCD administration. Although ABCD increased concentrations of AmB in the reticuloendothelial system, increased toxicity was not observed in these organs.


Assuntos
Anfotericina B/farmacocinética , Anfotericina B/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Ésteres do Colesterol , Coloides , Cães , Feminino , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Distribuição Tecidual
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