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101.
The environmental health-related relevance of cyanobacteria is primarily related to their ability to produce a wide range of toxins, which are known to be hazardous to many organisms, including human beings. The occurrence of cyanobacterial blooms has been related to eutrophic surface water. In the bloom-forming process the levels of phosphorus and nitrogen have been well documented but information regarding concentrations of other chemicals (inorganic, organo-metallic, and organic) is still incipient. Several contaminants, like trace metals, elicit a variety of acute and chronic toxicity effects, but cyanobacteria also have the capability to accumulate, detoxify, or metabolize such substances, to some extent. The role of cyanobacterial exudates has been proved a means of both nutrient acquisition and detoxification. In addition, cyanobacteria are effective biological metal sorbents, representing an important sink for metals in aquatic environment. Understanding the fundamental physicochemical mechanisms of trace metal bio-uptake by cyanobacteria in natural systems is a step towards identifying under what conditions cyanobacterial growth is favored and to ascertain the mechanisms by which blooms (and toxin production) are triggered. In this review the cyanobacterial interactions with metals will be discussed, focusing on freshwater systems. 相似文献
102.
Vasconcelos Camila Vilela Costa Alan Carlos Müller Caroline Castoldi Gustavo Costa Andréia Mendes de Paula Barbosa Kássia Rodrigues Arthur Almeida da Silva Adinan Alves 《Ecotoxicology (London, England)》2020,29(2):203-216
Ecotoxicology - Common bean (Phaseolus vulgaris) cultivation occurs mainly in regions with acidic soils, where high aluminum (Al) concentration is a major constraint to crop production. In this... 相似文献
103.
Fernando Tadeu Vasconcelos Amaral Paulo Henrique Manso André Schmidt Ricardo Nilson Sgarbieri Walter Villela de Andrade Vicente Clovis Carbone Junior Jane Somerville 《Brazilian Journal Of Cardiovascular Surgery》2015,30(3):373-379
During the last decades, advances in diagnosis and treatment of congenital heart
disease have allowed many individuals to reach adulthood. Due mainly to the great
diagnostic diversity and to the co-morbidities usually present in this age group,
these patients demand assistance in a multidisciplinary facility if an adequate
attention is aimed. In this paper we reviewed, based in the international literature
and also on the authors’ experience, the structural conditions that should be
available for these patients. We highlighted aspects like the facility
characteristics, the criteria usually adopted for patient transfer from the
paediatric setting, the composition of the medical and para- medical staff taking
into account the specific problems, and also the model of outpatient and in-hospital
assistance. We also emphasized the importance of patient data storage, the
fundamental necessity of institutional support and also the compromise to offer
professional training. The crucial relevance of clinical research is also approached,
particularly the development of multicenter studies as an appropriate methodology for
this heterogeneous patient population. 相似文献
104.
105.
IgG autoantibodies eluted from RBCs of antiglobulin positive normal blood donors contained at least two antibody populations, an IgG autoantibody (Ab 1), and an IgG population (Ab 2) that agglutinated RBCs coated with some Rh(D) alloantibodies. Eight of 24 autoantibody eluates tested agglutinated 3 of 10 anti-Rh(D) sensitized RBCs. The agglutinating activity was inhibited specifically by preincubation of the autoantibody eluate with the reactive anti-D. The reaction did not require the Fc domain of the anti-Rh(D), since autoantibody eluates agglutinated RBCs coated with F(ab')2 prepared from the reactive anti-D sera. These findings indicate that the RBCs of some antiglobulin- positive blood donors contain an immunoglobulin auto-antiidiotype (Ab 2) against the RBC autoantibody (Ab 1) which is demonstrable through its cross-reactivity with selected Rh(D) alloantibodies. Identification of auto-antiidiotypes in RBC autoimmunity lends support to the idiotype- antiidiotype network hypothesis of immune regulation and is consistent with the bizarre and complex serology of autoimmune hemolytic anemia. The absence of clinical hemolysis in antiglobulin-positive normal blood donors suggests that immunoglobulin idiotype-antiidiotype interactions may play a role in modulating the effects of RBC autoimmunity. 相似文献
106.
We treated 51 patients with advanced malignant lymphoma refractory to conventional therapy with methyl-glyoxal-bis(guanylhydrazone) (methyl- GAG) at doses ranging from 400 to 800 mg/sq m. Therapy was started on a weekly schedule and was switched to every other week in responding patients at the onset of toxicity. Partial responses were observed in 6 of 13 evaluable patients with Hodgkin's disease (46%), 5 of 10 patients with diffuse poorly differentiated lymphocytic lymphoma (50%), 2 of 4 patients with nodular poorly differentiated lymphocytic lymphoma (50%), and 3 of 13 patients with diffuse histiocytic lymphoma (23%). Two of six patients with mycosis fungoides showed objective improvement in cutaneous disease. Toxicity was generally mild and included muscular weakness, myalgia, mucositis, and diarrhea; two patients developed bronchospasm following drug infusions. We conclude that methyl-GAG has major antitumor activity when administered on this schedule to patients with advanced malignant lymphoma. The low degree of toxicity, unique mechanism of action, and minimal myelosuppressive effects suggest that methyl-GAG will prove useful in future trials of combination chemotherapy regimens for the treatment of lymphoma. 相似文献
107.
Patient perspectives on de‐simplifying their single‐tablet co‐formulated antiretroviral therapy for societal cost savings
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Objectives
The incremental costs of expanding antiretroviral (ARV) drug treatment to all HIV‐infected patients are substantial, so cost‐saving initiatives are important. Our objectives were to determine the acceptability and financial impact of de‐simplifying (i.e. switching) more expensive single‐tablet formulations (STFs) to less expensive generic‐based multi‐tablet components. We determined physician and patient perceptions and acceptance of STF de‐simplification within the context of a publicly funded ARV budget.Methods
Programme costs were calculated for patients on ARVs followed at the Southern Alberta Clinic, Canada during 2016 (Cdn$). We focused on patients receiving Triumeq® and determined the savings if patients de‐simplified to eligible generic co‐formulations. We surveyed all prescribing physicians and a convenience sample of patients taking Triumeq® to see if, for budgetary purposes, they felt that de‐simplification would be acceptable.Results
Of 1780 patients receiving ARVs, 62% (n = 1038) were on STF; 58% (n = 607) of patients on STF were on Triumeq®. The total annual cost of ARVs was $26 222 760. The cost for Triumeq® was $8 292 600. If every patient on Triumeq® switched to generic abacavir/lamivudine and Tivicay® (dolutegravir), total costs would decrease by $4 325 040. All physicians (n = 13) felt that de‐simplifying could be safely achieved. Forty‐eight per cent of 221 patients surveyed were agreeable to de‐simplifying for altruistic reasons, 27% said no, and 25% said maybe.Conclusions
De‐simplifying Triumeq® generates large cost savings. Additional savings could be achieved by de‐simplifying other STFs. Both physicians and patients agreed that selective de‐simplification was acceptable; however, it may not be acceptable to every patient. Monitoring the medical and cost impacts of de‐simplification strategies seems warranted.108.
Hypovitaminosis D has been reported in tropical countries, but this hormone has seldom been studied in Brazil. Our purpose
was to study the prevalence of hypovitaminosis D in patients hospitalized in internal medicine wards in Southern Brazil. Possible
associated factors were studied. We studied 81 adult patients in early spring. Mean serum 25(OH)D was 12±8.57 ng/mL; hypovitaminosis
D was severe (<10 ng/mL) in 27 (33.3%) patients, and moderate (≥10 ng/mL and <20 ng/mL) in 36 (44.5%) patients. Clinical evaluation
did not yield any data associated with hypovitaminosis D. Serum 25(OH)D levels of up to 20 ng/mL were associated with decreased
mean serum total calcium (p=0.001), ionized calcium (p=0.01), and phosphorus (p=0.044) levels, and increased mean serum PTH level (p=0.001). In a multiple regression model, serum PTH level was independently affected by serum total calcium (p=0.01), phosphorus (p=0.009), and albumin (p=0.009) levels. Hypovitaminosis D patients had lower mean serum albumin levels (p=0.004), and serum 25(OH)D levels were directly correlated to serum albumin levels (p<0.0001). Albumin influenced independently PTH response to hypovitaminosis D; normoalbuminemic hypovitaminosis D patients
had higher mean serum PTH than hypoalbuminemic patients. Conclusion: Hypovitaminosis D prevalence was very high in medical
inpatients in Southern Brazil, in early spring. Nevertheless, secondary hyperparathyroidism was less intense in hypoalbuminemic
hypovitaminosis D patients suggesting that in these patients free serum 25(OH)D was closer to normal. 相似文献
109.
Silvana Daher Costa Geraldo Bezerra da Silva Jr. Camilla Neves Jacinto Lorena Vasconcelos Mesquita Martiniano Yago Sucupira Amaral Fernando Jose Villar Nogueira Paes Maria Luiza De Mattos Brito Oliveira Sales Ronaldo de Matos Esmeraldo Elizabeth De Francesco Daher 《The American journal of tropical medicine and hygiene》2015,93(2):394-396
Few studies have focused on Rift Valley fever virus (RVFV) transmission in less arid, transitional landscapes surrounding known high-risk regions. The objective of this study was to identify evidence of RVFV exposure in Bodhei Village in a forested area at the edge of the RVFV-epidemic Garissa region. In a household cluster-based survey conducted between epidemics in early 2006, 211 participants were enrolled. Overall seroprevalence for anti-RVFV was high (18%) and comparable with rates in the more arid, dense brush regions farther north. Seroprevalence of adults was 28%, whereas that of children was significantly lower (3%; P < 0.001); the youngest positive child was age 3 years. Males were more likely to be seropositive than females (25% versus 11%; P < 0.01), and animal husbandry activities (birthing, sheltering, and butchering) were strongly associated with seropositivity. The results confirm that significant RVFV transmission occurs outside of recognized high-risk areas and independent of known epidemic periods. 相似文献
110.
Paulo Roberto Santos Diego Levi Silveira Monteiro Paulo Henrique Alexandre de Paula Vicente Lopes Monte Neto Maria Leilah Ponte Monte Coelho Cecília Costa Arcanjo Sânkia Maria Lopes Aragão Camila Barbosa Gondim Janaína Teixeira Pereira Carneiro Tapeti Hyngridd Soares Mendes Luise Vasconcelos Vieira Rita de Cássia Parente Prado 《Nephrology (Carlton, Vic.)》2015,20(8):519-522