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Marengo J, Espinoza JC, Bettolli L, Cunha AP, Molina-Carpio J, Skansi M, Correa K, Ramos AM, Salinas R, Sierra JP. A cold wave of winter 2021 in central South America: characteristics and impacts. Clim Dyn 2023; 61:1-23. [PMID: 36820313 PMCID: PMC9933029 DOI: 10.1007/s00382-023-06701-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
During the austral winter (June-August) of 2021, the meteorological services of Brazil, Argentina, Peru, Paraguay, Bolivia, and Chile all issued forecasts for unusually cold conditions. Record-low minimum temperatures and cold spells were documented, including one strong cold wave episode that affected 5 countries. In this study, we define a cold wave as a period in which daily maximum and minimum air temperatures are below the corresponding climatological 10th percentile for three or more consecutive days. The intense cold wave event in the last week of June, 2021, resulted in record-breaking minimum daily temperatures in several places in central South America and Chile. Several locations had temperatures about 10 °C below average, central South America had freezing conditions, and southern Brazil even saw snow. The cold air surge was characterized by an intense upper-air trough located close to 35° S and 70° W. The southerly flow to the west of this trough brought very cold air northward into subtropical and tropical South America. A northward flow between the lower-level cyclonic and anticyclonic perturbations caused the intense southerly flow between the upper-level ridge and trough. This condition facilitated the inflow of near-surface cold air from southern Argentina into southeastern Brazil and tropical South America east of the Andes. In the city of São Paulo, the cold wave caused the death of 13 homeless people from hypothermia. Frost and snow across southern and southeastern Brazil caused significant damage to coffee, sugarcane, oranges, grapes, and other fruit and vegetable crops. Wine and coffee production fell, the latter by 30%, and prices of food and commodities in the region rose. Supplementary Information The online version contains supplementary material available at 10.1007/s00382-023-06701-1.
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Affiliation(s)
- J. Marengo
- Centro Nacional de Monitoramento e Alerta de Desastres Naturais, CEMADEN, Estrada Doutor Altino Bondensan, São José Dos Campos, São Paulo, Brazil
| | - J. C. Espinoza
- Institut des Géosciences de l’Environnement, Université Grenoble Alpes, IRD, CNRS, Grenoble, France
| | - L. Bettolli
- UBA, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - A. P. Cunha
- Centro Nacional de Monitoramento e Alerta de Desastres Naturais, CEMADEN, Estrada Doutor Altino Bondensan, São José Dos Campos, São Paulo, Brazil
| | - J. Molina-Carpio
- Universidad Mayor de San Andrés, Instituto de Hidraulica e Hidrología, La Paz, Bolivia
| | - M. Skansi
- SMN, Servicio Meteorologico Nacional, SMN, Buenos Aires, Argentina
| | - K. Correa
- SENAMHI, Servicio Nacional de Meteorologia e Hidrologia, Lima, Peru
| | - A. M. Ramos
- Instituto Nacional de Meteorologia, INMET, Brasilia, Brazil
| | - R. Salinas
- Dirección de Meteorología e Hidrología/Dirección Nacional de Aeronáutica Civil, Asunción, Paraguay
| | - J.-P. Sierra
- Institut des Géosciences de l’Environnement, Université Grenoble Alpes, IRD, CNRS, Grenoble, France
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Moraes AF, Moreira Filho RNF, Passos CCO, Cunha AP, Silva LMAE, Freitas LBN, Vasconcelos NF, Ricardo NMPS, Canuto KM, Rosa MF, Leal LKAM, Vieira RS. Hemocompatibility of 2‐
N
‐3,6‐
O
‐sulfated chitosan films. J Appl Polym Sci 2018. [DOI: 10.1002/app.47128] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- A. F. Moraes
- Departamento de Engenharia QuímicaUniversidade Federal do Ceará, Centro de Tecnologia Avenue Mister Hull, s/n ‐ Campus do Pici ‐ Bloco 709 Pici. CEP, 60455‐760, Fortaleza, Ceará Brazil
| | - R. N. F. Moreira Filho
- Departamento de Engenharia QuímicaUniversidade Federal do Ceará, Centro de Tecnologia Avenue Mister Hull, s/n ‐ Campus do Pici ‐ Bloco 709 Pici. CEP, 60455‐760, Fortaleza, Ceará Brazil
| | - C. C. O. Passos
- Centro de Estudos Farmacêuticos e CosméticosUniversidade Federal do Ceará CEP 60430‐370 Fortaleza Ceará Brazil
| | - A. P. Cunha
- Laboratório de Polímeros e Inovação de MateriaisUniversidade Federal do Ceará CEP 60455‐760 Fortaleza Ceará Brazil
| | - L. M. A e Silva
- Embrapa Agroindústria Tropical CEP 60020‐181 Fortaleza Ceará Brazil
| | - L. B. N. Freitas
- Centro de Estudos Farmacêuticos e CosméticosUniversidade Federal do Ceará CEP 60430‐370 Fortaleza Ceará Brazil
| | | | - N. M. P. S. Ricardo
- Laboratório de Polímeros e Inovação de MateriaisUniversidade Federal do Ceará CEP 60455‐760 Fortaleza Ceará Brazil
| | - K. M. Canuto
- Embrapa Agroindústria Tropical CEP 60020‐181 Fortaleza Ceará Brazil
| | - M. F. Rosa
- Embrapa Agroindústria Tropical CEP 60020‐181 Fortaleza Ceará Brazil
| | - L. K. A. M. Leal
- Centro de Estudos Farmacêuticos e CosméticosUniversidade Federal do Ceará CEP 60430‐370 Fortaleza Ceará Brazil
| | - R. S. Vieira
- Departamento de Engenharia QuímicaUniversidade Federal do Ceará, Centro de Tecnologia Avenue Mister Hull, s/n ‐ Campus do Pici ‐ Bloco 709 Pici. CEP, 60455‐760, Fortaleza, Ceará Brazil
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Vide J, Moreira C, Cunha AP, Baldaia H, Magina S, Azevedo F. Generalized Bullous Fixed Drug Eruption due to Bromhexine. Dermatol Online J 2016. [DOI: 10.5070/d3227031650] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Vide J, Moreira C, Cunha AP, Baldaia H, Magina S, Azevedo F. Generalized Bullous Fixed Drug Eruption due to Bromhexine. Dermatol Online J 2016; 22:13030/qt7nt074w4. [PMID: 27617726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 07/15/2016] [Indexed: 06/06/2023] Open
Abstract
We describe a patient with a generalized bullous form of Fixed Drug Eruption (FDE) induced by bromhexine, a commonly used drug for respiratory symptoms. This is a rare association and generalized bullous FDE is also very rare. We emphasize the importance of patch tests in identifying the culprit drug.
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Affiliation(s)
- J Vide
- Department of Dermatology and Venereology, Centro Hospitalar de São João EPE, Porto, Portugal.
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Giordano JO, Wiltbank MC, Guenther JN, Pawlisch R, Bas S, Cunha AP, Fricke PM. Increased fertility in lactating dairy cows resynchronized with Double-Ovsynch compared with Ovsynch initiated 32 d after timed artificial insemination. J Dairy Sci 2012; 95:639-53. [PMID: 22281329 DOI: 10.3168/jds.2011-4418] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Accepted: 10/04/2011] [Indexed: 11/19/2022]
Abstract
The objective was to determine if using a Double-Ovsynch protocol [DO; Pre-Resynch: GnRH-7 d-PGF(2α)-3 d-GnRH, 7 d later Breeding-Resynch: GnRH-7 d-PGF(2α)-56 h-GnRH-16 h-timed artificial insemination (TAI)] to resynchronize ovulation after a previous TAI would increase synchrony and pregnancies per AI (P/AI) compared with an Ovsynch protocol initiated 32 d after TAI (D32; GnRH-7 d-PGF(2α)-56 h-GnRH-16 h-TAI). Lactating Holstein cows at various days in milk and prior AI services were blocked by parity and randomly assigned to resynchronization treatments. All DO cows received the first GnRH injection of Pre-Resynch 22 d after TAI, and cows (n=981) diagnosed not pregnant using transrectal ultrasonography 29 d after TAI continued the protocol. Pregnancy status for all D32 cows was evaluated 29 d after TAI so fertility and pregnancy loss could be compared with that of DO cows. All D32 cows received the first GnRH injection of Ovsynch 32 d after TAI, and cows (n=956) diagnosed not pregnant using transrectal palpation 39 d after TAI continued the protocol. In a subgroup of cows from each treatment, ultrasonography (n=751) and serum progesterone (P4) concentrations (n=743) were used to determine the presence of a functional corpus luteum (CL) and ovulation to the first GnRH injection of D32 and Breeding-Resynch of DO (GnRH1), luteal regression after PGF before TAI, and ovulation to the GnRH injection before TAI (GnRH2). Overall, P/AI 29 d after TAI was not affected by parity and was greater for DO compared with D32 cows (39 vs. 30%). Pregnancy loss from 29 to 74 d after TAI was not affected by parity or treatment. The percentage of cows with a functional CL (P4 ≥1.0 ng/mL) at GnRH1 was greater for DO than D32 cows (81 vs. 58%), with most DO cows having medium P4 (60%; 1.0 to 3.49 ng/ml), whereas most D32 cows had either low (42%; <1.0 ng/mL) or high (36%; ≥3.5 ng/mL) P4 at GnRH1. Ovulation to GnRH1 was similar between treatments but was affected by serum P4 at GnRH. Cows with low P4 (<1.0 ng/mL) had the greatest ovulatory response (59%), followed by cows with medium (≥1.0 to 3.49 ng/mL; 38%) and then high (≥3.50 ng/mL; 16%) P4 at GnRH1. A greater percentage of DO cows were synchronized compared with D32 cows (72 vs. 51%) primarily due to a greater percentage of D32 than DO cows without a functional CL at the PGF injection before TAI (35 vs. 17%) or without complete CL regression before GnRH2 (17 vs. 7%). We conclude that DO increased fertility of lactating dairy cows during a resynchronization program primarily by increasing synchronization of cows during the Ovsynch protocol before TAI.
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Affiliation(s)
- J O Giordano
- Department of Dairy Science, University of Wisconsin, Madison 53706, USA
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Souza AH, Cunha AP, Silva EPB, Gümen A, Ayres H, Guenther JN, Wiltbank MC. Comparison of gonadorelin products in lactating dairy cows: efficacy based on induction of ovulation of an accessory follicle and circulating luteinizing hormone profiles. Theriogenology 2009; 72:271-9. [PMID: 19394072 DOI: 10.1016/j.theriogenology.2009.02.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Revised: 02/25/2009] [Accepted: 02/26/2009] [Indexed: 11/26/2022]
Abstract
This study evaluated whether the four gonadorelin products that are commercially available in the United States produce comparable ovulation responses in lactating cows. Dairy cows at 7 d after last gonadotropin-releasing hormone (GnRH) treatment of Ovsynch (Day 7), with a corpus luteum (CL) > or =15 mm and at least one follicle > or =10mm, were evaluated for response to GnRH treatment. Selected cows were randomized to receive (100 microg; im): (1) Cystorelin (n=146); (2) Factrel (n=132); (3) Fertagyl (n=140); or (4) Ovacyst (n=140). On Day 14, cows were examined for ovulation by detection of an accessory CL. Circulating luteinizing hormone (LH) concentrations were also evaluated in some cows after treatment with 100 microg (n=10 per group) or 50 microg (n=5 per group) GnRH. Statistical analyses were performed with the procedures MIXED and GLIMMIX of the SAS program. Percentage of cows ovulating differed (P<0.01) among groups, with that for Factrel being lower (55.3%) than that for Cystorelin (76.7%), Fertagyl (73.6%), or Ovacyst (85.0%). There was no effect of batch, parity, or follicle size on ovulation response, but increasing body condition score decreased ovulation response. There was a much greater LH release in cows treated with 100 microg than in those treated with 50 microg, but there were no detectable differences among products in time to LH peak, peak LH concentration, or area under the LH curve and no treatment effects nor treatment by time interactions on circulating LH profile. Thus, ovulation response to Factrel on Day 7 of the cycle was lower than that for other commercial GnRH products, although a definitive mechanism for this difference between products was not demonstrated.
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Affiliation(s)
- A H Souza
- Department of Dairy Science, University of Wisconsin, Madison, WI, USA
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Santos AL, Cunha AP, Barros AM, Barros MA. P58
Multisensitization to plants: clinical case. Contact Dermatitis 2008. [DOI: 10.1111/j.0105-1873.2004.0309gn.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Brusveen DJ, Cunha AP, Silva CD, Cunha PM, Sterry RA, Silva EPB, Guenther JN, Wiltbank MC. Altering the time of the second gonadotropin-releasing hormone injection and artificial insemination (AI) during Ovsynch affects pregnancies per AI in lactating dairy cows. J Dairy Sci 2008; 91:1044-52. [PMID: 18292260 DOI: 10.3168/jds.2007-0409] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Based on previous research, we hypothesized that Cosynch at 72 h [GnRH-7 d-PGF(2alpha)-72 h-GnRH + artificial insemination (AI)] would result in a greater number of pregnancies per AI (P/AI) than Cosynch at 48 h. Further, we hypothesized that P/AI would be improved to a greater extent when GnRH was administered at 56 h after PGF(2alpha) before AI at 72 h due to a more optimal interval between the LH surge and AI. Nine hundred twenty-seven lactating dairy cows (n = 1,507 AI) were blocked by pen, and pens rotated through treatments. All cows received GnRH followed 7 d later by PGF(2alpha) and then received one of the following: 1) GnRH + timed AI 48 h after PGF(2alpha) (Cosynch-48); 2) GnRH 56 h after PGF(2alpha) + timed AI 72 h after PGF(2alpha) (Ovsynch-56); or 3) GnRH + timed AI 72 h after PGF(2alpha) (Cosynch-72). Pregnancy diagnoses were performed by ultrasound at 31 to 33 d post-AI and again at 52 to 54 d post-AI. Overall P/AI were similar for the Cosynch-48 (29.2%) and Cosynch-72 (25.4%) groups. The Ovsynch-56 group had a greater P/AI (38.6%) than Cosynch-48 or Cosynch-72. Presynchronized first-service animals had greater P/AI than cows at later services in Cosynch-48 (36.2 vs. 23.0%) and Ovsynch-56 (44.8 vs. 32.7%) but not in Cosynch-72 (24.6 vs. 26.2%). Similarly, primiparous cows had greater P/AI than multiparous cows in Cosynch-48 (34.1 vs. 22.9%) and Ovsynch-56 (41.3 vs. 32.6%), but not Cosynch-72 (29.8 vs. 25.3%). In conclusion, we found no advantage to Cosynch at 72 h vs. 48 h. In contrast, we found a clear advantage to treating with GnRH at 56 h, 16 h before a 72-h AI, probably because of more-optimal timing of AI before ovulation.
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Affiliation(s)
- D J Brusveen
- Department of Dairy Science, University of Wisconsin, Madison 53706, USA
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Souza AH, Gümen A, Silva EPB, Cunha AP, Guenther JN, Peto CM, Caraviello DZ, Wiltbank MC. Supplementation with Estradiol-17β Before the Last Gonadotropin-Releasing Hormone Injection of the Ovsynch Protocol in Lactating Dairy Cows. J Dairy Sci 2007; 90:4623-34. [PMID: 17881683 DOI: 10.3168/jds.2007-0172] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The aim of this study was to determine whether an increase in circulating estrogen concentrations would increase percentage pregnant per artificial insemination (PP/AI) in a timed AI protocol in high-producing lactating dairy cows. We analyzed only cows having a synchronized ovulation to the last GnRH of the Ovsynch protocol (867/1,084). The control group (n = 420) received Ovsynch (GnRH--7 d--PGF(2alpha)--56 h--GnRH--16 h--timed AI). The treatment group (n = 447) had the same timed AI protocol with the addition of 1 mg of estradiol-17beta (E2) at 8 h before the second GnRH injection. Ovarian ultrasound and blood samples were taken just before E2 treatment of both groups. In a subset of cows (n = 563), pressure-activated estrus detection devices were used to assess expression of estrus at 48 to 72 h after PGF(2alpha) treatment. Ovulation was confirmed by ultrasound 7 d after timed AI. Treatment with E2 increased expression of estrus but overall PP/AI did not differ between E2 and control cows. There was an interaction between treatment and expression of estrus such that PP/AI was greater in E2-treated cows that showed estrus than in E2-treated or control cows that did not show estrus and tended to be greater than control cows that showed estrus. There was evidence for a treatment by ovulatory follicle size interaction on PP/AI. Supplementation with E2 improved PP/AI in cows ovulating medium (15 to 19 mm) but not smaller or larger follicles. The E2 treatment also tended to improve PP/AI in primiparous cows with low (< or =2.5) body condition score, and in cows at first postpartum service compared with Ovsynch alone. In conclusion, any improvements in PP/AI because of E2 treatment during a timed AI protocol appear to depend on expression of estrus, parity, body condition score, and size of ovulatory follicle.
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Affiliation(s)
- A H Souza
- Department of Dairy Science, University of Wisconsin, Madison 53706, USA
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Cavadas C, Fontes Ribeiro CA, Santos MS, Cunha AP, Macedo T, Caramona MM, Cotrim MD. In vitro study of the interaction of Tilia europeae L. aqueous extract with GABAA receptors in rat brain. Phytother Res 1999. [DOI: 10.1002/(sici)1099-1573(199702)11:1<17::aid-ptr948>3.0.co;2-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abstract
The antioxidant activities of methanol and ethyl ether extracts obtained from Thymus zygis, collected during the flowering or non-flowering period, were evaluated and compared. To investigate this potential, extracts were tested on their capacity to react with diphenylpicrylhydrazyl (DPPH) in a homogeneous medium, and to inhibit Fe2+/ascorbate-induced membrane lipid peroxidation, as estimated by the formation of thiobarbituric acid-reactive substances (TBARS). Although methanol extracts reduce DPPH radicals more efficiently than ethyl ether extracts, suggesting a potent radical scavenger activity, the ethyl ether extracts were found to be most active in inhibiting lipid peroxidation in sarcoplasmic reticulum (SR) membranes. In addition, both extracts present peroxyl and superoxide radical scavenging activities. Peroxyl radicals were generated by the water soluble 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) azoinitiator, and the scavenging activities of the extracts were measured by the inhibition of cis-parinaric acid (PnA) fluorescence decay in SR. Superoxide radicals were generated either by an enzymatic or a non-enzymatic system, and the scavenger ability was evaluated by the inhibition of nitroblue tetrazolium reduction. Methanolic extracts are more potent as scavengers of peroxyl and superoxide radicals than the ethyl ether extracts. Apparently, there is a relationship between antioxidant potency and the total phenolic groups content in each extract.
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Affiliation(s)
- J R Soares
- Laboratório de Bioquímica, Faculdade de Farmácia, Universidade de Coimbra, Portugal
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Cavadas C, Araújo I, Cotrim MD, Amaral T, Cunha AP, Macedo T, Ribeiro CF. In vitro study on the interaction of Valeriana officinalis L. extracts and their amino acids on GABAA receptor in rat brain. Arzneimittelforschung 1995; 45:753-5. [PMID: 8573216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This work studied in vitro the interaction of aqueous and hydroalcoholic extracts of Valeriana officinalis L. and compounds that are present in the extracts (amino acids and valerenic acid) with the GABAA (gamma-aminobutyric acid) receptor, using the [3H] muscimol binding technique to crude synaptic membranes from rat brain cortices. Both extracts displaced [3H]muscimol bound and this effect is probably due only to their amino acid content, specially GABA. This fact explains the in vitro effect of valerian extracts on GABAA receptor but not their sedative effect.
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Affiliation(s)
- C Cavadas
- Laboratory of Pharmacology, Faculty of Medicine, University of Coimbra, Portugal
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Santos MS, Ferreira F, Faro C, Pires E, Carvalho AP, Cunha AP, Macedo T. The amount of GABA present in aqueous extracts of valerian is sufficient to account for [3H]GABA release in synaptosomes. Planta Med 1994; 60:475-476. [PMID: 7997482 DOI: 10.1055/s-2006-959538] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Santos MS, Ferreira F, Cunha AP, Carvalho AP, Macedo T. An aqueous extract of valerian influences the transport of GABA in synaptosomes. Planta Med 1994; 60:278-279. [PMID: 8073095 DOI: 10.1055/s-2006-959476] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Santos MS, Ferreira F, Cunha AP, Carvalho AP, Ribeiro CF, Macedo T. Synaptosomal GABA release as influenced by valerian root extract--involvement of the GABA carrier. Arch Int Pharmacodyn Ther 1994; 327:220-31. [PMID: 7979830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The effect of an aqueous extract obtained from the roots of Valeriana officinalis was investigated on the uptake and release of GABA in synaptosomes isolated from rat brain cortex. Aqueous extract of valerian inhibited the uptake and stimulated the release of [3H]GABA, either in the absence or in the presence of K+ depolarization. The release was Na(+)-dependent and independent of the presence of Ca2+ in the external medium. It is concluded that valerian extract releases [3H]GABA by reversal of the GABA carrier, which is Na(+)-dependent and Ca(2+)-independent. This increase in [3H]GABA release appears to be independent from Na(+)-K(+)-ATPase activity and the membrane potential.
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Affiliation(s)
- M S Santos
- Department of Zoology, Faculty of Medicine, University of Coimbra, Portugal
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