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Tamara T Perry Perla A Vargas Jeremy Bufford Charles Feild Michael Flick Pippa M Simpson Robert G Hamilton Stacie M Jones 《Annals of allergy, asthma & immunology》2008,100(4):358-363
BACKGROUND: The impact of preschool environmental conditions on classroom aeroallergen concentrations is not fully understood. OBJECTIVE: To examine the relationship between school environmental conditions and classroom aeroallergen concentrations in the Pulaski County Head Start (HS) Program. METHODS: Thirty-three HS centers in Pulaski County, Arkansas, underwent a detailed environmental evaluation. Classroom settled dust samples were analyzed for the presence of common indoor allergens. RESULTS: Classroom eating (70%), wall-to-wall carpeting (58%), and water damage (33%) were common. Median classroom allergen levels were as follows: dust mite (Der p 1 and Der f 1), 0.6 microg/g; Fel d 1, 0.4 microg/g; Can f 1, 1.7 microg/g; cockroach, below detection; Mus m 1, 0.18 microg/g; and mold spores, 17,800 CFU/g. Can f 1 and Mus m 1 allergens were detected in 100% of HS centers. Facilities with carpeting, increased humidity, and single-use facilities showed trends toward increased dust mite concentrations. Detectable cockroach allergen was more common in classrooms cleaned by teachers than by professional housekeepers. CONCLUSIONS: Aeroallergens were commonly detected in Pulaski County HS center classrooms, with dog and mouse allergens detected in 100% of centers. Median classroom allergen concentrations were low, and classroom characteristics were not strongly predictive of increased allergen exposure. 相似文献
3.
Judith K. Brown Perla Subbaiah Therese Sarah 《Journal of cross-cultural gerontology》1994,9(2):231-254
Our cross-cultural study of the relationship between older women and their younger female kin examines women's hierarchies based on age and focuses on the exercise of authority by women, when such authority is traditional and accepted. Data were collected for two world-wide samples each consisting of 30 societies, varying in complexity, subsistence base, geographic location, and in customs related to women's lives. Three hypotheses were tested. The findings, which are statistically significant, suggest that the relationships between older women and their younger female kin are patterned and predictable, determined by the role of women in subsistence activities, by rules for post-marital residence, and by descent.When domination can only be exercised... directly, between one person and another, it can not take place overtly and must be disguised under the veil of enchanted relationships, the official model of which is presented by the relations between kinsmen.The gentle, invisible form of violence, which is never recognized as such... can not fail to be seen as the most economical mode of domination...The system is such that the dominant agents have a vested interest in virtue. (Bourdieu 1991191, 192, 194) 相似文献
4.
Sonia Galván-Arzate José Pedraza-Chaverrí Omar N Medina-Campos Perla D Maldonado Beatriz Vázquez-Román Camilo Ríos Abel Santamaría 《Food and chemical toxicology》2005,43(7):1037-1045
Thallium (Tl+) toxicity has been related with the generation of reactive oxygen species (ROS) and oxidative stress (OS) in the central nervous system. Since changes in endogenous antioxidant systems might contribute to acute Tl+-induced OS and neurotoxicity, in this study we measured the metal concentration and the levels of lipid peroxidation (LP) in different brain regions (hypothalamus (Ht); cerebellum (Ce); striatum (S); hippocampus (Hc) and frontal cortex (Cx)) in possible correlation with the content of reduced glutathione (GSH), the activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD), and the animal performance in behavioral tests, all evaluated after a single administration of thallium acetate (8 or 16 mg/kg, i.p.) to rats. Seven days after Tl+ administration, the metal was homogeneously and dose-dependently accumulated in all regions evaluated. LP was increased in Ht, Ce and S, while GSH was depleted in S. Cu,Zn-SOD activity was also decreased in Ht and S. All these changes occurred with 16 mg/kg dose and at 7 days after treatment, but not at 1 or 3 days. In addition, Tl+-treated animals exhibited general hypokinesis, but no changes were observed in spatial learning. Our findings suggest that a delayed response of the brain to Tl+ may be the result of its residual levels. Also, despite the regional alterations produced by Tl+ in LP and the limited changes in endogenous antioxidants, there is a correlation between the Tl+-induced oxidative damage and the affected behavioral tasks, suggesting that, although still moderate, Tl+ evokes neurotoxic patterns under the experimental conditions tested. 相似文献
5.
Schmidt AP Lara DR de Faria Maraschin J da Silveira Perla A Onofre Souza D 《Brain research》2000,864(1):40-43
In the mammalian CNS, glutamate and GABA are the principal neurotransmitters mediating excitatory and inhibitory synaptic events, respectively, and have been implicated in the neurobiology of seizures. Guanine-based purines, including the nucleoside guanosine and the nucleotide GMP, have been shown to antagonize glutamatergic activity at the receptor level and the other purine nucleoside adenosine is a well-known modulator of seizure threshold. In the present study we investigated the anticonvulsant effect of i. p. guanosine and GMP against seizures induced by the glutamate agonist quinolinic acid (QA) or the GABA(A) antagonist picrotoxin in mice. Animals were pretreated with an i.p. injection of saline, guanosine or GMP 30 min before either an i.c.v. injection of 4 microliter QA (36.8 nmol) or a subcutaneous injection of picrotoxin (3.2 mg/kg). All animals pretreated with vehicle followed by QA or picrotoxin presented seizures, which were completely prevented by the NMDA antagonist MK-801 and the GABA agonist phenobarbital, respectively. Guanosine and GMP dose-dependently protected against QA-induced seizures, up to 70 and 80% at 7.5 mg/kg, with ED(50)=2. 6+/-0.4 and 1.7+/-0.6 mg/kg, respectively. Conversely, neither guanosine, GMP nor MK-801 affected picrotoxin-induced seizures, indicating some degree of specificity towards the glutamatergic system. This study suggests anticonvulsant properties of i.p. guanosine and GMP, which may be related with antagonism of glutamate receptors. 相似文献
6.
S-allylcysteine scavenges singlet oxygen and hypochlorous acid and protects LLC-PK(1) cells of potassium dichromate-induced toxicity. 总被引:1,自引:0,他引:1
Omar Noel Medina-Campos Diana Barrera Sabina Segoviano-Murillo Diana Rocha Perla D. Maldonado Nicandro Mendoza-Patiño José Pedraza-Chaverri 《Food and chemical toxicology》2007,45(10):2030-2039
It has been found that S-allylcysteine (SAC), a garlic-derived compound, has in vivo and in vitro antioxidant properties. In addition, it is known that SAC is able to scavenge different reactive oxygen or nitrogen species including superoxide anion (O(2)(-)), hydrogen peroxide (H(2)O(2)), hydroxyl radical (OH()), and peroxynitrite anion (ONOO(-)) although the IC(5O) values for each reactive species has not been calculated and the potential ability of SAC to scavenge singlet oxygen ((1)O(2)) and hypochlorous acid (HOCl) has not been explored. The purposes of this work was (a) to explore the potential ability of SAC to scavenge (1)O(2) and HOCl, (b) to further characterize the O(2)(-), H(2)O(2), OH(), and ONOO(-) scavenging ability of SAC by measuring the IC(50) values using in vitro assays, and (c) to explore the potential ability of SAC to ameliorate the potassium dichromate (K(2)Cr(2)O(7))-induced cytotoxicity in LLC-PK1 cells in which oxidative stress is involved. The scavenging activity was compared against the following reference compounds: N-acetylcysteine for O(2)(-), sodium pyruvate for H(2)O(2), dimethylthiourea for OH(), lipoic acid and glutathione for (1)O(2), lipoic acid for HOCl, and penicillamine for ONOO(-). It was found that SAC was able to scavenge concentration-dependently all the species assayed with the following IC(5O) (mean+/-SEM, mM): O(2)(-) (14.49+/-1.67), H(2)O(2) (68+/-1.92), OH() (0.68+/-0.06), (1)O(2) (1.93+/-0.27), HOCl (2.86+/-0.15), and ONOO(-) (0.80+/-0.05). When the ability of SAC to scavenge these species was compared to those of the reference compounds it was found that the efficacy of SAC (a) to scavenge O(2)(-), H(2)O(2), OH(), and ONOO(-) was lower, (b) to scavenge HOCl was similar, and (c) to scavenge (1)O(2) was higher. In addition, it was found that SAC was able to prevent K(2)Cr(2)O(7)-induced toxicity in LLC-PK1 cells in culture. It was showed for the first time that SAC is able to scavenge (1)O(2) and HOCl and to ameliorate the K(2)Cr(2)O(7)-induced toxicity. 相似文献
7.
Patrizia Santi Stefano Pagnotta Vincenzo Palleschi Maria Perla Colombini Alberto Renzulli 《Materials》2022,15(11)
A macroscopic lithological study and physical (hardness, size, weight) investigations, coupled with laser-induced breakdown spectroscopy (LIBS) and X-ray fluorescence (XRF) chemical analyses of three egg- and one pear-shaped polished black stones, exposed in the library of the child home of the famous poet Giacomo Leopardi, at Recanati (Italy), were carried out. They are characterized by different sizes: two with the same weight of 16.9 kg and the two smaller ones of 5.6 kg each, corresponding to multiples of standard roman weights (drachma and scrupulum). These features and the presence of some grooves on the rock artefacts, probably for grappling hooks, suggest an original use as counterweight for the four black stones herein classified as amphibole-bearing serpentinites whose lithologies are far away from Recanati (probably coming from geological outcrops in Tuscany). The four serpentinite stones closely match with the so-called Lapis Aequipondus used in antiquity by the Romans as counterweights. Due to the presence of lead rings or iron hooks in these stones, Lapis Aequipondus were also used for martyrdoms during the persecution of Christians in the Roman period, attached to the necks of martyrs that were then thrown in the wells or attached to the ankles of hanging bodies. This is the reason why these stones are also known as Lapis Martyrum, venerated with the relative martyrs, in several churches of Rome. The four black stones investigated probably arrived at Recanati from Rome after the middle of the 19th century. In the past, Christians also called Lapis Martyrum the “devil’s stones” (Lapis Diaboli). This could also be the reason for the popular belief that black stones cannot be touched by people, except those of the Leopardi dynasty. This work contributes to the cultural heritage of Leopardi’s child home, as the four black stones had never been investigated. 相似文献
8.
IB de Groot AM Stiggelbout PJ van der Boog AG Baranski PJ Marang-van de Mheen;for the PARTNER-study group 《Transplant international》2012,25(9):967-975
Health related quality of life (HRQoL) of living kidney donors on average is good, but some donors experience a low HRQoL after donation. This study assessed the prevalence of reduced HRQoL and explored associations with pre‐ and post‐donation variables. 316 donors (response rate 74%) who donated a kidney between 1997 and 2009 filled in a questionnaire. HRQoL was measured using the Short‐Form 36; fatigue using the Multidimensional Fatigue Inventory; societal participation using the Utrecht Scale for Evaluation of Rehabilitation‐Participation. Donors on average had better HRQoL than the general population. However, 12% had a reduced physical (PCS) and 18% a reduced mental (MCS) HRQoL. Donors with reduced HRQoL reported greater fatigue (P < 0.01), lower societal participation (P < 0.01) and showed a trend towards statistical significance in experiencing more donor–recipient relationship changes (P = 0.07). Prior to donation, donors with reduced PCS had a higher BMI (P < 0.05) and more often smoked (P < 0.05). Donors with reduced MCS had higher expectations (P < 0.05). Reduced HRQoL is associated with higher BMI, smoking and higher expectations prior to donation. These results may be used to develop a screening instrument to select donors at high risk for reduced HRQoL. 相似文献
9.
Amelia Oliveira Dana Warcel Nancy Huntley Perla Eleftheriou John B. Porter 《Hemoglobin》2016,40(2):127-129
A female proband homozygous for both Hb Luton [α89(FG1)His→Leu (CAC>CTC), HBA2: c.269A>T (or HBA1)], a high oxygen affinity hemoglobin (Hb), and for α+-thalassemia (α-thal), (–α4.2, leftward deletion) was first described in 2012. This is a follow-up report of the same case. At the age of 18, the described patient presented with progressively worsening lethargy, headaches, dizziness, syncope and Raynaud’s phenomenon. Following extensive cardiological and neurological investigation, it was felt that significant erythrocytosis was the most likely cause. Venesection followed by regular exchange transfusions were arranged with marked amelioration in symptomatology. In the vast majority of cases of high oxygen affinity Hbs, venesection is not recommended due to the asymptomatic phenotype and reduced oxygen delivery resulting from venesection. This update describes the evolving phenotype of this unique proband and, to the best of our knowledge, the first use of regular, long-term therapeutic red cell exchange transfusions in a case of high affinity Hb. 相似文献
10.