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1.
Front Cardiovasc Med ; 9: 997452, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386340

RESUMO

Background: Increased wave reflections assessed by pulse wave analysis (PWA) was proposed as one of the potential culprits of hypertension seen in women with pregnancy-associated hypertension (PAH). However, this statement has never been confirmed with "Wave Separation Analysis" (WSA), a more sophisticated mathematical approach that analyzes the amplitude and interaction between forward and backward aortic pressure waveform components. Objective: To characterize potential changes in pressure wave components of PAH compared to healthy non-pregnant (NP) women and women with normal pregnancies (HP) by using WSA and compared these findings with PWA-derived indexes; secondarily, to evaluate differences in WSA-derived indexes between subgroups of PAH (i.e., preeclampsia [PE] and gestational hypertension [GH]). Methods: Using radial and carotid applanation tonometry, we quantified in HP (n = 10), PAH (n = 16), and NP (n = 401): (i) PWA-derived indexes; (ii) WSA-derived indexes: forward (Pf) and backward (Pb) waveform components, backward component arrival time (PbAT), reflection magnitude (RM = Pb/Pf) and index [RIx = Pb/(Pf + Pb)]. Results: While PAH was associated with a higher Pf compared to HP and NP, Pb and PbAT were similar between the groups. Both GH and PE showed a higher Pf compared to HP, but only PE had a trend of presenting with higher Pb and lower PbAT compared to the other groups. Finally, PAH showed a trend of having lower RM and RIx compared to NP and HP, with no differences between GH and PE. Conclusion: PAH was associated with higher Pf, but not higher Pb, compared to NP and HP, although PE also demonstrated a trend of higher Pb.

3.
Curr Hypertens Rev ; 18(1): 17-33, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33602097

RESUMO

BACKGROUND: Preeclampsia (PE) is a pregnancy complication with serious maternal and neonatal consequences worldwide. Our understanding of PE pathophysiology has significantly evolved over the last decades by recognizing that endothelial dysfunction and systemic inflammation, with an associated angiogenic imbalance, are key pieces of this incomplete puzzle. In the present era, where no single treatment to cure or treat this obstetric condition has been developed so far, PE prevention and early prediction are the most useful clinical approach to reduce the PE burden. INTRODUCTION: Although most PE episodes occur in healthy nulliparous women, the identification of specific clinical conditions that increase the risk of PE dramatically provides a critical opportunity to improve outcomes by acting on potentially reversible factors, and also contributes to better understand this pathophysiologic enigma. METHODS: Pertinent studies were searched in PubMed/Medline and Google Scholar (updated August 2020) using common keywords applied in the field of preeclampsia, inflammation and endothelial dysfunction. Given the design of this work as a narrative review, no formal criteria for study selection or appraisal were utilized. CONCLUSION: In this review, we highlight major clinical contributors of PE and shed light on their potential link with endothelial dysfunction and inflammation.


Assuntos
Obstetrícia , Pré-Eclâmpsia , Feminino , Humanos , Recém-Nascido , Inflamação/diagnóstico , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/terapia , Gravidez
4.
Am J Physiol Heart Circ Physiol ; 320(5): H2011-H2030, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33797272

RESUMO

Preeclampsia is a worldwide pregnancy complication with serious short- and long-term maternal and neonatal consequences. Our understanding of preeclampsia pathophysiology has significantly evolved over the last decades with the recognition that impaired arterial function and structure may occur early in the course of pregnancy, preceding the clinic-humoral syndrome and driving long-term cardiovascular disease risk in the future of these patients. Although an early abnormal placentation may be the inciting event for a large proportion of cases, there is growing evidence that challenges the placental hypothesis in all affected women, since placental histopathology lesions thought to be characteristic are neither sensitive nor specific markers for the disorder. Recent hemodynamic investigations and studies on left ventricular function and structure in women with preeclampsia further challenge this universal paradigm and propose that placental dysfunction could be secondary to a maternal cardiovascular maladaptation to pregnancy in certain patients. Supporting this hypothesis, certain vascular features, which are characteristically enhanced in normal pregnancy allowing a healthy vascular adaptation, are absent in preeclampsia and comparable to the nonpregnant population. However, arterial biomechanics in preeclampsia may only not cope with hemodynamic demands of pregnancy but also impose additional detrimental loads to the maternal heart ("impaired left-ventricle-aorta coupling") and transmit pressure and flow disturbances into the fetoplacental circulation ("impaired large arteries-microcirculation coupling"). In this review, we analyze the major role of the arterial dysfunction in the cardiovascular maladaptation hypothesis of preeclampsia, shed light on its potential etiopathogenic link, and discuss the complementary nature of the placental and cardiovascular theories.


Assuntos
Artérias/fisiopatologia , Endotélio Vascular/fisiopatologia , Hemodinâmica/fisiologia , Pré-Eclâmpsia/fisiopatologia , Rigidez Vascular/fisiologia , Espessura Intima-Media Carotídea , Feminino , Humanos , Placenta/irrigação sanguínea , Gravidez
5.
Trop Anim Health Prod ; 53(1): 186, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649872

RESUMO

The aim of this study was to evaluate the effects of dietary inclusion of palm kernel cake (PKC) on the feeding behavior of feedlot-finished cattle. Forty uncastrated crossbred bulls with an average age of 24.2 ± 2 months and an average weight of 331.1 ± 36.2 kg were distributed into four treatment groups in a completely randomized design with ten replicates. The treatments consisted of 0, 8, 16, or 24% PKC inclusion in the diet (dry matter basis). Palm kernel cake inclusion influenced feeding time (P < 0.05), which increased linearly. The inclusion of the ingredient also affected (P < 0.05) rumination time (min/day), total chewing time, and the time spent on other activities. The number of cuds ruminated per day showed a linear response to the PKC inclusion levels (P < 0.05). The number of feeding bouts increased linearly (P < 0.05). Dry matter (DM) intake and DM feeding efficiency decreased linearly (P < 0.05). There were no effects of PKC inclusion (P > 0.05) on neutral detergent fiber feeding (NDF) efficiency or DM rumination efficiency. NDF rumination efficiency increased linearly (P < 0.05). Palm kernel cake can be included at levels up to 24% in the total diet of feedlot-finished crossbred bulls, as it does not affect their dry matter intake or feeding behavior.


Assuntos
Ração Animal , Comportamento Alimentar , Ração Animal/análise , Animais , Peso Corporal , Bovinos , Dieta/veterinária , Fibras na Dieta , Digestão , Masculino
6.
Hum Reprod Update ; 27(4): 651-672, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-33748839

RESUMO

BACKGROUND: Despite significant advances in our understanding of the pathophysiology of preeclampsia (PE), there are still many unknowns and controversies in the field. Women undergoing frozen-thawed embryo transfer (FET) to a hormonally prepared endometrium have been found to have an unexpected increased risk of PE compared to women who receive embryos in a natural FET cycle. The differences in risk have been hypothesized to be related to the absence or presence of a functioning corpus luteum (CL). OBJECTIVE AND RATIONALE: To evaluate the literature on secretory products of the CL that could be essential for a healthy pregnancy and could reduce the risk of PE in the setting of FET. SEARCH METHODS: For this review, pertinent studies were searched in PubMed/Medline (updated June 2020) using common keywords applied in the field of assisted reproductive technologies, CL physiology and preeclampsia. We also screened the complete list of references in recent publications in English (both animal and human studies) on the topics investigated. Given the design of this work as a narrative review, no formal criteria for study selection or appraisal were utilized. OUTCOMES: The CL is a major source of multiple factors regulating reproduction. Progesterone, estradiol, relaxin and vasoactive and angiogenic substances produced by the CL have important roles in regulating its functional lifespan and are also secreted into the circulation to act remotely during early stages of pregnancy. Beyond the known actions of progesterone and estradiol on the uterus in early pregnancy, their metabolites have angiogenic properties that may optimize implantation and placentation. Serum levels of relaxin are almost undetectable in pregnant women without a CL, which precludes some maternal cardiovascular and renal adaptations to early pregnancy. We suggest that an imbalance in steroid hormones and their metabolites and polypeptides influencing early physiologic processes such as decidualization, implantation, angiogenesis and maternal haemodynamics could contribute to the increased PE risk among women undergoing programmed FET cycles. WIDER IMPLICATIONS: A better understanding of the critical roles of the secretory products of the CL during early pregnancy holds the promise of improving the efficacy and safety of ART based on programmed FET cycles.


Assuntos
Pré-Eclâmpsia , Animais , Corpo Lúteo/metabolismo , Transferência Embrionária/efeitos adversos , Feminino , Humanos , Pré-Eclâmpsia/etiologia , Gravidez , Progesterona/metabolismo , Técnicas de Reprodução Assistida/efeitos adversos
7.
Front Cardiovasc Med ; 8: 766723, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35004884

RESUMO

Background: Non-pregnant (NP) women have a progressive increase in arterial stiffness from central-to-peripheral arteries ["stiffness gradient" (SG)], which is of physiologic importance since excessive pulsatility is filtered by the creation of wave reflections. If the aorta gets stiff with minimal or no change in the periphery, the SG is dissipated transmitting pressure disturbances to the microcirculation. It remains unknown the status of the SG in both women with healthy pregnancies (HP) and complicated by pregnancy-associated hypertension (PAH). Objective: To determine whether HP and PAH are associated with changes in SG. Secondarily, we aim at identifying potential differences between the subgroups of PAH (pre-eclampsia and gestational hypertension). Methods: HP (n = 10), PAH (n = 16), and healthy NP women (n = 401, to be matched for age, and cardiovascular risk with the pregnant women) were included. Carotid-to-femoral (cfPWV) and carotid-to-radial pulse wave velocity (crPWV), common carotid artery (CCA) and brachial artery (BA) diameters and elastic modulus (EM), and regional (cfPWV/crPWV or "PWV ratio") and local (CCA EM/BA EM or "EM ratio") SG were quantified. Results: HP showed no changes in PWV ratio compared with NP, in the presence of significantly lower cfPWV and crPWV. HP exhibited higher arterial diameters and lower CCA EM/BA EM compared to NP, without differences with PAH. PAH was associated with a significant increase in the PWV ratio that exceeded the levels of both NP and HP, explained by a lower (although significant) reduction of cfPWV with respect to that observed in HP with respect to NP, and a higher reduction in crPWV with respect to that observed between HP and NP. The blunted reduction in cfPWV observed in PAH coincided with an increase in the CCA EM. Conclusions: Compared with NP, HP was associated with unchanged PWV ratio but with a reduction in CCA EM/BA EM, in the setting of a generalized drop in arterial stiffness. Compared with NP and HP, PAH was associated with an "exaggerated rise" in the PWV ratio without changes in CCA EM/BA EM, in the setting of a blunt reduction in cfPWV but exaggerated crPWV drop. The SG attenuation/reversal in PAH was mainly driven by pre-eclampsia.

8.
Trop Anim Health Prod ; 50(1): 105-111, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28944436

RESUMO

The aim of this study was to evaluate the correlation between production performance and feeding behavior of steers reared on pasture during the rainy-dry transition period. Twenty-two ½ Holstein-Zebu crossbred steers at an average age of 10 months and with an average initial body weight of 234.5 ± 16.0 kg were distributed in a completely randomized design with two types of supplementation and eleven replications. Pearson's linear correlation analysis was performed between behavioral variables and weight gain and feed conversion. Correlation coefficients were tested by the t test. The time expended feeding at the trough was positively correlated (P < 0.05) with average daily gain (ADG) and with the number of periods of permanence at the trough. Bite rate and the number of bites per day were positively correlated (P < 0.05) with ADG and negatively (P < 0.05) with feed conversion, unlike the number of bites per swallow, which was negatively correlated (P < 0.05) with ADG. There was a positive correlation (P < 0.05) between feed efficiency in dry matter and neutral detergent fiber and ADG. Feeding behavior characteristics have little association with the production performance of cattle on pasture receiving mineral or energy-protein supplementation.


Assuntos
Bovinos/fisiologia , Dieta/veterinária , Comportamento Alimentar , Aumento de Peso , Ração Animal/análise , Animais , Brasil , Masculino , Chuva , Distribuição Aleatória , Estações do Ano
10.
BMC Complement Altern Med ; 16: 83, 2016 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-26921197

RESUMO

BACKGROUND: The Amazon is the largest rainforest in the world and is home to a rich biodiversity of medicinal plants. Several of these plants are used by the local population for the treatment of diseases, many of those with probable anti-inflammatory effect. The aim of the present investigation was to evaluate the in vitro antioxidant and anti-peroxidases potential of the ethanol extracts of five plants from the Brazilian Amazon (Byrsonima japurensis, Calycophyllum spruceanum, Maytenus guyanensis, Passiflora nitida and Ptychopetalum olacoides). METHODS: DPPH, ABTS, superoxide anion radical, singlet oxygen and the ß-carotene bleaching methods were employed for characterization of free radical scavenging activity. Also, total polyphenols were determined. Antioxidant activities were evaluated using murine fibroblast NIH3T3 cell. Inhibition of HRP and MPO were evaluated using amplex red® as susbtract. RESULTS: The stem bark extracts of C. spruceanum and M. guyanensis provided the highest free radical scavenging activities. C. spruceanum exhibited IC50 = 7.5 ± 0.9, 5.0 ± 0.1, 18.2 ± 3.0 and 92.4 ± 24.8 µg/mL for DPPH(•), ABTS(+•), O2 (-•) and (1)O2 assays, respectively. P. olacoides and C. spruceanum extracts also inhibited free radicals formation in the cell-based assay. At a concentration of 100 µg/mL, the extracts of C. spruceanum, B. japurensis inhibited horseradish peroxidase by 62 and 50 %, respectively. C. spruceanum, M. guyanensis, B. japurensis also inhibited myeloperoxidase in 72, 67 and 56 %, respectively. CONCLUSIONS: This work supports the folk use these species that inhibited peroxidases and exhibited significant free radical scavenging and antioxidant activities what can be related to treatment of inflammation.


Assuntos
Antioxidantes/farmacologia , Malpighiaceae/química , Maytenus/química , Olacaceae/química , Passiflora/química , Peroxidases/antagonistas & inibidores , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Brasil , Humanos , Medicina Tradicional , Camundongos , Células NIH 3T3 , Peroxidase , Fitoterapia , Plantas Medicinais/química , Polifenóis/análise , Polifenóis/farmacologia
11.
Rev. bras. farmacogn ; 25(3): 264-268, May-June 2015. ilus
Artigo em Inglês | LILACS | ID: lil-757433

RESUMO

AbstractIn Amazonas State (Brazil), Justicia acuminatissima (Miq.) Bremek., Acanthaceae, leaf teas are used in folk medicine to treat several inflammatory illnesses. In order to validate this medicinal application, we analyzed the acute toxicity and antioxidant, antiedematogenic and antinociceptive potentials of an aqueous extract of this species, using culture cells and animal models. The aqueous extract did not cause toxic effects on human lymphocytes in high concentration (400 μg/ml), neither on mice treated with high doses (5000 mg/kg) in an acute toxicity analysis by oral route, and also did not cause lesions in the gastric mucosa of animals treated with 300 mg/kg, which was the maximal dose used in the anti-inflammatory screening. The aqueous extract caused inhibition of inflammatory pain in formalin-induced paw licking test with all tested doses, 30, 100 and 300 mg/kg, and antiedematogenic activity at 100 and 300 mg/kg. Additionally, the aqueous extract presented statistically significant action on the release of nitric oxide by lipopolysaccharide-activated macrophages. These results and other preliminary studies support the folk use of this species, and further investigation of its action mechanism by inhibition of COX-2 or related metabolite would be interesting.

12.
Rev. bras. farmacogn ; 22(6): 1212-1218, Nov.-Dec. 2012. ilus
Artigo em Inglês | LILACS | ID: lil-659056

RESUMO

Justicia acuminatissima (Miq.) Bremek., Acanthaceae, is a subshrub found in northern Brazil, where it is widely used by the population of this region as an anti-inflammatory medicine. Despite this popular use, there is no pharmacognostical data to support the correct identification of this species. We therefore performed a morpho-anatomical, histochemical and phytochemical analysis of the leaves of this species, using well-known methods. The leaves are simple, exstipulate, green on the surfaces, and pubescent, with a lanceolate shape, crenate margin, pinnate venation and decussate phyllotaxy. The parenchyma is palisade and spongy, and its vascular system is bilateral. Glandular and non-glandular trichome and cystoliths were also detected. There are diacytic stomata on both the adaxial and abaxial surfaces of epidermis. Histochemical tests revealed the presence of phenolic compounds, amide and protein. Phytochemical tests showed the presence of coumarins, tannins, catechins, saponins and steroids.

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