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Kiperstok A, Silva CM. The responsibility of the pulp and paper sector with regard to sustainable development: how much is enough? WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2007; 55:65-71. [PMID: 17486836 DOI: 10.2166/wst.2007.213] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Pulp and paper companies all over the world certify their environmental management systems assuming public commitments for the continuous improvement of their relationship with the environment. Once certified, they consider themselves having done their part. But is this enough? This work has been carried out with the clear intention of provoking the professionals who can give the much needed answers for the construction of environmental sustainability in the pulp and paper sector.
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Oliveira CR, Silva CM, Milanez AF. Application of ultrafiltration in the pulp and paper industry: metals removal and whitewater reuse. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2007; 55:117-23. [PMID: 17486842 DOI: 10.2166/wst.2007.219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
In the pulp and paper industry, the water use minimization is a constant target. One way to reduce water use is to recycle the effluent in a closed-cycle concept. In paper mills, the main source of liquid effluent is the so-called whitewater, which is the excess water, originated from pulp stock dewatering and other fibre contaminated water. This research studied the reuse of paper mill whitewater after membrane ultrafiltration (UF) in the paper machine and in the pulp bleach plant of an integrated mill. Contaminant removal and flux behaviour of the UF system were evaluated. The treatment by ultrafiltration was technically feasible and the treated whitewater had good potential to be reused in some processes in the paper machine. The reuse of ultrafiltered whitewater in the bleaching plant was not recommended because of the high level of soluble calcium present in this stream. Therefore, a combined treatment of the whitewater using the principle of precipitation and ultrafiltration was proposed showing good results and enabling the use of the treated whitewater in the bleach plant.
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Silva CM, Gonçalves GA, Farias TL, Mendes-Lopes JMC. A tank-to-wheel analysis tool for energy and emissions studies in road vehicles. THE SCIENCE OF THE TOTAL ENVIRONMENT 2006; 367:441-7. [PMID: 16546238 DOI: 10.1016/j.scitotenv.2006.02.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2005] [Revised: 02/10/2006] [Accepted: 02/14/2006] [Indexed: 05/07/2023]
Abstract
Currently, oil based fuels are the primary energy source of road transport. The growing need for oil independence and CO(2) mitigation has lead to the increasing importance of alternative fuel usage. CO(2) is produced not only as the fuel is used in the vehicle (tank-to-wheel contribution), but also upstream, from the fuel extraction to the refueling station (well-to-tank contribution), and the life cycle of the fuel production (well-to-wheel contribution) must be considered in order to analyse the global impact of the fuel utilization. A road vehicle tank-to-wheel analysis tool that may be integrated with well-to-tank models was developed in the present study. The integration in a demonstration case study allowed to perform a life cycle assessment concerning the utilization of diesel and natural gas fuels in a specific network line of a bus transit company operating in the city of Porto, Portugal.
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Duarte A, Avena K, Sampaio A, Melo E, Sena E, Teles J, Leite M, Espírito-santo D, Messeder O, Silva C, David C. Crit Care 2003; 7:P46. [DOI: 10.1186/cc2242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Vargas EA, Preis RA, Castro L, Silva CM. Co-occurrence of aflatoxins B1, B2, G1, G2, zearalenone and fumonisin B1 in Brazilian corn. FOOD ADDITIVES AND CONTAMINANTS 2001; 18:981-6. [PMID: 11665739 DOI: 10.1080/02652030110046190] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Two hundred and fourteen unprocessed corn samples (1997-98 harvest), collected at wholesale markets in different regions in Brazil, were surveyed for the occurrence of mycotoxins. The samples were analysed for aflatoxins B1, B2, G1, G2, zearalenone and fumonisin B1 using in-house validated methods. The occurrence of aflatoxin B1, zearalenone and fumonisin B1 was found in 38.3, 30.4 and 99.1% of the samples, respectively. Aflatoxin B1, zearalenone and fumonisin B1 contamination levels varied from 0.2 to 129, 36.8 to 719, and 200 to 6100 microg/kg, respectively. The co-occurrence of the two carcinogenic mycotoxins aflatoxin B1 and fumonisin B1 was observed in 100% of the aflatoxin-contaminated samples (82 samples). Co-occurrences of aflatoxin B1: zearalenone: fumonisin B1 and aflatoxin B1: aflatoxin B2: fumonisin B1 were found in 18 and 43 samples, respectively.
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França AV, De Souza JB, Silva CM, Soares EC. Long-term prognosis of cirrhosis after spontaneous bacterial peritonitis treated with ceftriaxone. J Clin Gastroenterol 2001; 33:295-8. [PMID: 11588542 DOI: 10.1097/00004836-200110000-00007] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Spontaneous bacterial peritonitis (SBP) is a frequent infection in cirrhotic patients with ascites, with a poor prognosis. The aims of this study were to determine the long-term survival of cirrhotic patients with SBP treated with ceftriaxone and to identify predictive factors related to survival. We studied 47 first episodes of SBP treated with ceftriaxone with a mean follow-up of 272 days. Nineteen variables were recorded to evaluate their relation to survival. The most frequent organism that caused SBP was Escherichia coli (40%). Spontaneous bacterial peritonitis resolution was achieved in 67% of patients. After resolution, SBP recurrence was observed in 44% of patients. The cumulative probability of survival was 68.1% at 1 month and 30.8% at 6 months. After uni-and multivariate analyses of all cases, SBP resolution ( p = 0.0001) and international normalized ratio (INR) ( p = 0.0057) were found to be related to survival. Another analysis performed after SBP resolution and SBP recurrence showed that ascitic fluid-positive culture ( p = 0.0344) and INR ( p = 0.0218) had statistical significance as variables predictive of long-term survival. We conclude that the survival of cirrhotic patients is very short after the first episode of SBP, a fact probably related to advanced liver disease, as liver dysfunction (INR) is the most important factor related to long-term patient survival.
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Pinto MF, Silva CM. [Predictive value of reactive strips in urinary infection]. ACTA MEDICA PORT 2001; 14:457-8. [PMID: 11878154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
The microbiologic method to confirm or not the diagnosis of urinary tract infection is usually the culture and Gram-stain of the clean-catch midstream urine. Nevertheless, this is a costly and time-consuming method. We tried to evaluate the positive and negative predictive value of the nitrite and leucocyte-esterase reactive strips as an alternative method. When both the two parameters are negative it is fairly safe to exclude the urinary tract infection.
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Medeiros JM, Silva CM, Sougey EB, Costa JA, Castro CM, Castro RM. Action of selective serotonin reuptake inhibitor on aggressive behavior in adult rat submitted to the neonatal malnutrition. ARQUIVOS DE NEURO-PSIQUIATRIA 2001; 59:499-503. [PMID: 11588625 DOI: 10.1590/s0004-282x2001000400004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effect of the malnutrition during suckling on the aggressiveness was investigated in adult rats treated or not with citalopram, a selective serotonin reuptake inhibitor (SSRI). The animals were divided into two groups according to the diet used: nourished group - the rats received the control diet with 23% protein during the life; and malnourished group - the rats had its mothers submitted to diet with 7.8% protein during suckling. At 120 days of age, each group was sub-divided according to the treatment: acute - consisting a single i.p. injection of saline solution or 20-mg/Kg citalopram; chronic - consisting the single injections (1 per day during 14 days) of saline or 20 mg/Kg citalopram. The acute or chronic treatment with SSRI reduces aggressive response in nourished rats, but not in malnourished ones. Thus, the malnutrition during the critical period of brain development seems to induce durable alterations in the function of the serotoninergic neurotransmission
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Silva CM, Vargas EA. A survey of zearalenone in corn using Romer Mycosep 224 column and high performance liquid chromatography. FOOD ADDITIVES AND CONTAMINANTS 2001; 18:39-45. [PMID: 11212546 DOI: 10.1080/02652030010002649] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A survey of zearalenone (ZEA) in corn from various regions of Brazil was carried out by the analysis of 380 corn samples, of which 30 samples (7.8%) were found to be contaminated in the range of 46.7-719 micrograms/kg. ZEA was extracted with acetonitrile-water (84:16, v/v), cleaned-up on a Romer Mycosep 224 column, separated, detected and quantified by high performance liquid chromatography (HPLC). The in-house method characteristics of linearity, accuracy, precision, and detection limit were defined by means of recovery tests with spiked corn samples in the range of 35.8-716 micrograms/kg and the analysis of a naturally-contaminated sample (n = 7). The mean recovery for ZEA was 99.4% and the relative standard deviation (RSD) varied from 0.7 to 26.6% in the range studied. The method has been shown to be accurate, quick and reliable for determination of zearalenone in corn.
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Periera da Silva A, Rocha R, Silva CM, Mira L, Duarte MF, Florêncio MH. Antioxidants in medicinal plant extracts. A research study of the antioxidant capacity of Crataegus, Hamamelis and Hydrastis. Phytother Res 2000; 14:612-6. [PMID: 11113998 DOI: 10.1002/1099-1573(200012)14:8<612::aid-ptr677>3.0.co;2-t] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The antioxidant capacity of extracts of Crataegus oxyacantha, Hamamelis virginiana, Hydrastis canadensis, plants native to Europe and North America which have long been used in herbal medicine for the treatment of cardiac and circulatory functions, has been investigated. The total antioxidant potential conferred by all hydrogen donating antioxidants present in these extracts has been assessed by the ABTS assay and the relative order of antioxidant potential has been established. Gas chromatography coupled to mass spectrometry (GC-MS) has been used for the chemical identification of the antioxidant volatile compounds present in the extracts. The GC-MS data were related to the results obtained using the ABTS assay.
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Viana GS, do Vale TG, Silva CM, Matos FJ. Anticonvulsant activity of essential oils and active principles from chemotypes of Lippia alba (Mill.) N.E. Brown. Biol Pharm Bull 2000; 23:1314-7. [PMID: 11085358 DOI: 10.1248/bpb.23.1314] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the present work we studied the anticonvulsive effects of the essential oils (EOs) from three chemotypes of Lippia alba (Mill.) N.E.Brown (Verbenaceae). Animals (female Swiss mice, 25 g) were treated with the EO and, 30 or 60 min after intraperitoneal (i.p.) or oral (p.o.) administration, respectively, injected with pentylenetetrazole (80 mg/kg, i.p.) and observed for 30 min. The results showed that EO I (200 and 400 mg/kg), EO II (100, 200 and 400 mg/kg), and EO III (400 mg/kg), i.p., produced an increased latency time for the first convulsion as related to controls. Death latency was greater in the groups receiving EO I (50 and 100 mg/kg), EO II (100 and 200 mg/kg), and EO III (200 mg/kg), i.p. Orally, while no effect was demonstrated with EOs at doses of 200 or 400 mg/kg, significant increases in the latency of convulsion and latency of death were observed with EO I at the highest dose (800 mg/kg). Similarly, EO III at this dose was also effective as far as latency of convulsion is concerned. Animals treated with citral (100 mg/kg, i.p.), beta-myrcene or limonene (200 mg/kg, i.p.), EOs chemical constituents, presented significant increases in the latency of convulsion and percentage of survival as compared to controls. After oral administration these effects were observed only with a higher dose (400 mg/kg). The association of EOs with diazepam significantly potentiated their effects, suggesting a similar mechanism of action and indicating that citral, beta-myrcene, and limonene are probably the EOs active compounds.
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Pirrung MC, Silva CM, Jaeger J. Available pathways database (APD): an essential resource for combinatorial biology. JOURNAL OF NATURAL PRODUCTS 2000; 63:1400-1405. [PMID: 11076562 DOI: 10.1021/np000244x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A relational database, the Available Pathways Database (APD), has been constructed of microbial natural products, their producing strains, and their biosynthetic pathways. The database allows the ready selection of donor strains for combinatorial biology experiments. It provides the same type of resource for combinatorial biology as the Available Chemicals Directory (ACD) does for combinatorial chemical library generation. Its cataloging ability can also provide insight into novel aspects of biosynthetic routes. In particular, no 10-unit Type I polyketides were found in the compilation of this edition of the APD (Version I).
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Silva CM, Severini MH, Sopelsa A, Coelho JC, Zaha A, d'Azzo A, Giugliani R. Six novel beta-galactosidase gene mutations in Brazilian patients with GM1-gangliosidosis. Hum Mutat 2000; 13:401-9. [PMID: 10338095 DOI: 10.1002/(sici)1098-1004(1999)13:5<401::aid-humu9>3.0.co;2-n] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
GM1-gangliosidosis is a lysosomal storage disease caused by a deficiency of acid beta-galactosidase. Three clinical forms are recognized-infantile, juvenile, and adult-based on age of onset and severity of the symptoms. We have performed molecular analysis of a large cohort of GM1 patients (19 Brazilian and one Uruguayan), using nonradioactive single-strand conformation polymorphism (SSCP) and restriction enzyme analysis of genomic DNA. Six novel mutations (R121S, V240M, D491N, 638-641insT, 895-896insC, 1622-1627insG) and two previously described point mutations (R59H, R208C) were identified. Together they accounted for 90% of the disease alleles of the patients. Two mutations, 1622-1627insG and R59H, were present in 18 of 20 patients. In addition, four polymorphisms (L10P, L12L, R521C, S532G) were identified. All cases reported are infantile GM1 gangliosidosis. This report constitutes the most comprehensive molecular study to date of this disorder in infantile patients. Since GM1-gangliosidosis is the most common lysosomal storage disorder in Southern Brazil, molecular diagnosis will be important for genetic counseling, carrier detection and prenatal diagnosis in index families.
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Deslandes SF, Gomes R, Silva CM. [Characterization of the cases of domestic violence against women assisted in 2 public hospitals of Rio de Janeiro]. CAD SAUDE PUBLICA 2000; 16:129-37. [PMID: 10738157 DOI: 10.1590/s0102-311x2000000100013] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This paper aims at: (a) to analyze the distribution of the cases of domestic violence against women (adolescent and adult) in relation to emergency care due to external causes; (b) to characterize the victims and the rendered care; (c) to analyze the circumstances in which events happened. In methodological terms, it tries to articulate the quantitative and qualitative approaches. The study was developed in two public hospitals of reference placed in the city of Rio de Janeiro. Of the 72 assisted women, most referred to the husband, the partner or the boyfriend as the aggressor (69.4%) and were beaten (70.4%) especially on the face and on the head. The study comes to the conclusion that the health services should provide a good clinical care and promote prevention's actions.
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López N, de Barros-Mazón S, Vilela MM, Silva CM, Ribeiro JD. Genetic and environmental influences on atopic immune response in early life. J Investig Allergol Clin Immunol 1999; 9:392-8. [PMID: 10664935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
The purpose of our study was to carry out a prospective follow-up of 114 newborns at term (including three pairs of twins), regarding clinical manifestations for atopy during the first year of life. Their IgE levels in cord blood samples, at 3, 6, 9 and 12 months of age were measured and the influence of race, sex, breast-feeding, maternal smoking, family income, month of birth, family history and personal manifestations of atopic disease were evaluated. Total serum immunoglobulin E was quantified by microparticle enzyme immuno-assay (MEIA). The study group consisted of 60 (53%) male neonates, 67 (59%) Caucasians and 47 (41%) blacks. In the clinical follow-up, 32 (28.1%) infants developed obvious atopic disease: 29 infants presented recurrent wheezing, two had cow's milk allergy and one had atopic dermatitis. Probable atopic disease developed in 12 (10.5%) infants, whereas 70 (61.4%) infants showed no manifestations. Cord blood IgE levels in infants with obvious atopic disease was higher when compared to those without (p = 0.024), with 70.97% sensitivity and 46.2% specificity. IgE levels were also significantly different up to 12 months in these groups (p = 0.0001), when the sensitivity was 82.1% and the specificity 54.1%. At this age, the IgE levels were higher in infants with obvious atopy than nonatopic disease in relation to male sex (p = 0.015), black race (p = 0.009), breast-feeding for less than 6 months (p = 0.011) and when the family income was less than three times the minimum wage (about US $300) (p = 0.006). There was no association between IgE levels and family history of atopy. We concluded that immune response for atopy was in a large degree influenced by environmental factors and serum IgE at 12 months was a good marker for identifying infants with risk of atopic disease in early life.
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Gomes R, Silva CM, Deslandes SF, Souza ER. [Evaluation of outpatient care for people with HIV/AIDS in Rio de Janeiro, from the user's perspective]. CAD SAUDE PUBLICA 1999; 15:789-97. [PMID: 10633201 DOI: 10.1590/s0102-311x1999000400013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
This article analyzes perceptions by people with HIV/AIDS towards five specialized units under the State Health Department, Rio de Janeiro, concerning the care provided there. The research was based on both quantitative and qualitative methods. Data from 228 questionnaires and 19 semi-structured interviews were analyzed. The results generally indicated a positive evaluation on the part of this group of health care users. One conclusion was that the positive evaluation was actually related to the quality of the services available to them. However, users seem to have low expectations toward the level of services public clinics generally provide.
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Mardini LB, Souza MA, Rabinovitch L, Alves RS, Silva CM. Field studies with the bacterial larvicide INPALBAC for Simulium spp. control in Rio Grande do Sul, Brazil. Mem Inst Oswaldo Cruz 1999; 94:679-81. [PMID: 10464417 DOI: 10.1590/s0074-02761999000500023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Silva CM, Duarte MF, Mira ML, Florêncio MH, Versluis K, Heck AJ. Copper and iron interactions with angiotensin-converting enzyme inhibitors. A study by fast-atom bombardment tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 1999; 13:1098-1103. [PMID: 10407284 DOI: 10.1002/(sici)1097-0231(19990630)13:12<1098::aid-rcm618>3.0.co;2-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Fast atom bombardment, combined with high-energy collision-induced tandem mass spectrometry, has been used to investigate gas-phase metal-ion interactions with captopril, enalaprilat and lisinopril, all angiotensin-converting enzyme inhibitors.Suggestions for the location of metal-binding sites are presented. For captopril, metal binding occurs most likely at both the sulphur and the nitrogen atom. For enalaprilat and lisinopril, binding preferably occurs at the amine nitrogen. Copyright 1999 John Wiley & Sons, Ltd.
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Santos RL, Silva CM, Ribeiro AF, Vasconcelos AC, Pesquero JL, Coelho SG, Serakides R, Reis SR. Effect of growth hormone and induced IGF-I release on germ cell population and apoptosis in the bovine testis. Theriogenology 1999; 51:975-84. [PMID: 10729019 DOI: 10.1016/s0093-691x(99)00043-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Bovine growth hormone has been used in dairy cattle to increase milk production,but it also increases the twin parturition rate. This effect is mediated by insulin-like growth factor-I (IGF-I), which prevents follicular atresia by hindering apoptosis of granulosa cells. The action of GH and IGF-I on testicular function remains unclear. The goal of this study, therefore, was to verify the effects of short-term administration of GH and induced IGF-I release on the number of testicular germ cells, testicular morphology, and apoptosis in the bovine testis. Twenty Zebu bulls were split into 2 groups. The bulls in Group 1 (n = 10) were treated with 2 subcutaneous injections of bovine GH (500 mg/bull) 7 d apart. Group 2 bulls (n = 10) received placebos under the same protocol. All of the bulls were slaughtered 14 d after the start of treatment. Fragments of the testis were collected, fixed in Bouin's solution, embedded in paraffin, and the sections stained with hematoxilin and eosin. The paraffin-embedded sections were also used for in situ detection of apoptotic cells. Blood samples were collected at slaughter to measure serum levels of IGF-I, FSH and LH. Neither the number of Stage I seminiferous epithelium germ cells and the morphometric parameters (tubular diameter, seminiferous epithelium height, and volumetric proportions of structural components) nor the blood levels of FSH and LH showed a significant difference between the 2 groups. However, the treated animals showed an increase in serum IGF-I (P<0.01). Apoptotic germ cells were detected in the testis of both groups, showing the same pattern and a stage-specific apoptosis pattern. Most of the labeled cells were spermatocytes. The localization of apoptotic germ cells did not differ between groups. These results suggest that short-term administration of GH does not affect bovine spermatogenesis in adult bulls.
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Clayton PE, Freeth JS, Whatmore AJ, Ayling RM, Norman MR, Silva CM. Signal transduction defects in growth hormone insensitivity. ACTA PAEDIATRICA (OSLO, NORWAY : 1992). SUPPLEMENT 1999; 88:174-8; discussion 179. [PMID: 10102076 DOI: 10.1111/j.1651-2227.1999.tb14382.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Growth hormone (GH) insensitivity is a heterogeneous condition that can result from mutations within the GH receptor (GHR) and that can be inherited as both an autosomal recessive and a dominant trait. However, evidence from a small number of growth hormone binding protein (GHBP)-positive families indicates that their GH insensitivity is independent of GHR mutations. Two of these families appear to have distinct abnormalities in GH signal transduction. Studies suggest that one family (classic Laron syndrome phenotype; designated family H) have a signalling defect close to the GHR, preventing activation of both the STAT and MAPK pathways, whereas the other family (less marked phenotype; family M) have a defect in activating MAPK but not the STAT pathway. The children studied here are specifically insensitive to GH and their defect must be exclusive to this signalling system. Thus, families with GHBP-positive GH insensitivity without GHR mutations are likely to be important models in which to study the specificity of GH signal transduction and the relationship between GH insensitive phenotype and signalling defect.
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Silva CM, Isgaard J, Thorner MO. Cytokines in endocrine function. ADVANCES IN PROTEIN CHEMISTRY 1999; 52:199-221. [PMID: 9917921 DOI: 10.1016/s0065-3233(08)60436-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Love DW, Whatmore AJ, Clayton PE, Silva CM. Growth hormone stimulation of the mitogen-activated protein kinase pathway is cell type specific. Endocrinology 1998; 139:1965-71. [PMID: 9528983 DOI: 10.1210/endo.139.4.5884] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The GH receptor is a member of the cytokine receptor superfamily. Studies in the 3T3-F442A mouse preadipocyte have shown that GH activates the Janus kinase (JAK2), the signal transducers and activators of transcription (STAT1, -3, and -5), and mitogen-activated protein (MAP) kinase. Our previous studies in the human IM-9 lymphocyte have shown that GH activates JAK2 and only STAT5 (not STAT1 or -3). In the studies presented here, we have investigated activation of the MAP kinase (MAPK) pathway in the IM-9 lymphocyte. Western blotting with antiphosphotyrosine-, anti-MAPK-, and anti-phospho-MAPK-specific antibodies as well in vitro kinase assays using a synthetic peptide substrate demonstrate that although GH (200 ng/ml) activates MAPK in 3T3-F442A cells (at 5 and 10 min of treatment), it does not activate MAPK in IM-9 lymphocytes at time points ranging from 5-60 min. Nevertheless, the phorbol ester phorbol 12-myristate 13-acetate (50 ng/ml) does activate MAPK in the IM-9 cell, and immunoprecipitation with specific antibodies indicates that this activation occurs through c-Raf-1. Although the 52- and 66-kDa forms of the adapter protein Shc are tyrosine phosphorylated in response to GH treatment in 3T3-F442A cells, we demonstrate that the predominant forms in IM-9 cells are the 52- and 46-kDa forms, and neither is tyrosine phosphorylated in response to GH. These studies further elucidate the differential signaling by GH in two cell types.
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Freeth JS, Silva CM, Whatmore AJ, Clayton PE. Activation of the signal transducers and activators of transcription signaling pathway by growth hormone (GH) in skin fibroblasts from normal and GH binding protein-positive Laron Syndrome children. Endocrinology 1998; 139:20-8. [PMID: 9421393 DOI: 10.1210/endo.139.1.5690] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We have previously described two families (H and M) with GH binding protein-positive Laron Syndrome (LS), proposed to have one or more post GHR signaling defects. In the present study, we have examined whether the signal transducers and activators of transcription (STAT) pathway is activated by GH in skin fibroblast cultures established from these LS children, to determine the level(s) at which GH insensitivity has occurred. On immunoblots, both normal and LS fibroblasts express JAK2 and STATs 1, 3, and 5. GH induced rapid tyrosine phosphorylation of a protein at approximately 93 kDa in normal fibroblasts, and Western blotting with STAT-specific antibodies revealed STAT5 activation (phosphorylation) by GH. To determine further the identity and the DNA binding characteristics of the STAT proteins that were activated by GH, EMSAs were performed using three DNA elements known to bind STAT proteins; m67, the high affinity c-sis-inducible element (SIE), the interferon response element (IRE), and the lactogenic hormone-responsive region (LHRR). GH failed to induce protein binding to the SIE or IRE in normal skin fibroblasts but did induce the formation of a specific complex with the LHRR. Induction by GH of this LHRR/protein complex, which could be supershifted partially by anti-STAT1 antisera and completely by anti-STAT5 antisera, was transient, maximal between 10 and 30 min and reduced by 60 min. GH also induced distinct LHRR/protein complexes in mouse 3T3-F442A fibroblasts and in human IM-9 lymphocytes, but supershift analysis revealed that these complexes contained STAT5 but not STAT1. Whereas no binding to the LHRR was observed in GH-treated H fibroblasts, GH induced binding to this element in M fibroblasts. These results demonstrate that 1) the JAK-STAT pathway is activated by GH in normal fibroblasts and that STATs 1 and 5 have a role in GH-dependent signaling in these cells; 2) GH activation of DNA/STAT binding is cell type- and species-specific; and 3) GH failed to activate the STAT pathway in H fibroblasts but induced STAT signaling in M fibroblasts, indicating that the site of GH resistance in the latter is likely to be located within another GH signaling pathway. These fibroblast cultures therefore provide unique models with which to further our understanding of the mechanisms of human GH signaling.
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Consoli RA, Santos BDS, Lamounier MA, Secundino NF, Rabinovitch L, Silva CM, Alves RS, Carneiro NF. Efficacy of a new formulation of Bacillus sphaericus 2362 against Culex quinquefasciatus (Diptera:Culicidae) in Montes Claros, Minas Gerais, Brazil. Mem Inst Oswaldo Cruz 1997; 92:571-3. [PMID: 9361756 DOI: 10.1590/s0074-02761997000400025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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Silva CM, Viana MB, Gontijo B, Fernandes RA, Pereira LB. [Giant hemangioma treated with interferon alpha-2a]. J Pediatr (Rio J) 1997; 73:277-80. [PMID: 14685404 DOI: 10.2223/jped.559] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
OBJECTIVE The authors describe a case of giant hemangioma treated with interferon alpha-2a and review the role of this drug and other therapeutic modalities in the management of vascular lesions. METHODS A seven month-old child with giant hemangioma and persistent bleeding, anemia and repeated infections was treated with interferon alpha-2a. The drug was administered at the dosage of 3 million units/m(2)/day, subcutaneously, for nine months. RESULTS Response to treatment was considered excellent, with regression of 90% of the lesion, control of bleeding, infection and anemia, and catch-up growth. No untoward effects were observed. CONCLUSION Interferon alpha-2a should be considered as a valid therapeutic option in selected cases of hemangioma in children.
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